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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. Utility patent application Ser. No. 09/448,311, filed Nov. 23, 1999, and issued Apr. 16, 2002, as U.S. Pat. No. 6,370,801.
TECHNICAL FIELD
The present invention relates generally to equipment using one tool member to collect and a second tool member cooperatively positioned to assist in collecting, and more particularly, to hydraulic powered tools mountable on a boom of a vehicle or stationary platform.
BACKGROUND OF THE INVENTION
Assemblies such as large grapples or buckets with a bucket extension or a lid have been employed in the past for collection and sorting of large and small objects or quantities of material. Many of these collection assemblies have two members such as a bucket and a bucket extension which are selectively operable to work together. The collection assembly is generally attached to a boom arm of a platform such as a vehicle. The two members of the collector assembly are positioned to cooperatively engage each other to assist in the collection operation. One member assists the other member by providing a complimentary function such as in the case of the bucket lid or extension providing the bucket with enlarged capacity extension in one position, or grasping therebetween materials scooped up by the bucket. In the case of a grapple, the two members grasp items therebetween.
Generally, means are provided to separately supply rotational torque to one or both members in order to move one member relative to the other member. The operational limitation of a particular collection assembly is directly dependent upon the maximum amount of torque that can be supplied to the members. If the torque is not sufficient, the object size or the quantity of the material collected is limited.
It will therefore be appreciated that there has long been a significant need for an improved collection assembly. It should include a torque-transmitting member which is able to reliably supply sufficient torque to perform rough work such as tearing down a building and more delicate work such as sorting bricks from wood for recycling. The present invention fulfills these needs and further provides other related advantages.
SUMMARY OF THE INVENTION
The present invention resides in a fluid-powered tool assembly usable with a stationary or movable support platform having an arm. The tool assembly includes an arm connection member pivotably connectable to the arm for rotation about a first axis. It also includes a first tool member, and a second tool member positioned to cooperate with the first tool member. The assembly includes a body having a longitudinal axis and one of the first and second members attached thereto for movement with the body. A shaft is rotatably disposed within the body in general alignment with the body axis for rotation about a second axis spaced apart from the first axis. The shaft has the other of the first and second tool members attached thereto for movement with the shaft. A linear-to-rotary torque transmission member is mounted for longitudinal movement within the body in response to selective application of pressurized fluid thereto. The torque-transmitting member engages the body and the shaft to translate longitudinal movement of the torque-transmitting member into rotational movement of the shaft relative to the body. The first and second tool members are rotatable relative to each other about the second axis by operation of the torque-transmitting member. The pivotal connection of the arm connection member to the arm allows rotation of the tool assembly as a unit about the first axis.
In some embodiments, the tool assembly includes a support housing sized to receive and support the body therein. In one embodiment the body has first and second end portions, and the first body end portion is attached to the support housing and the second body end portion is engaged by the support housing to restrict transverse movement of the second body end portion. The one of the first or second tool members attached to the body is indirectly attached to the body through the support housing in one embodiment.
In another embodiment, the tool assembly includes a lateral tilt assembly having an actuator operable to laterally tilt the first and second tool members relative to the arm. The arm connection member is attached to the lateral assembly. This embodiment may also include a rotation assembly to selectively rotate the tool assembly about a transverse axis. A disclosed embodiment uses a turntable bearing.
In certain embodiments, the shaft has first and second opposite shaft end portions with the other of the first and second tool members attached to both the first and second shaft end portions for movement with the shaft.
One embodiment of the invention further includes a vehicle frame to which the arm of the support platform is attached. The tool assembly is preferably attached to the arm.
Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a left side elevational view of a backhoe vehicle shown with a tool assembly embodying the present invention having a bucket and a bucket extension for a collection operation.
FIGS. 2 a - 2 d are enlarged, left side elevational views of the boom arm and the tool assembly of FIG. 1 removed from the vehicle, with the bucket shown in various rotational positions relative to the boom arm and the bucket extension shown in various rotational positions relative to the bucket.
FIG. 3 is an enlarged, front elevational, sectional view of the fluid-powered rotary actuator of FIG. 1 used to rotate the bucket extension relative to the bucket shown without attachment members for the boom arm.
FIG. 4 is an enlarged, front elevational, sectional view of the tool assembly of FIG. 1 shown removed from the boom arm using an alternative manner of attaching the bucket to the actuator body.
FIG. 5 is a front elevational view of the tool assembly of FIG. 4 .
FIG. 6 is a left side elevational view of the tool assembly of FIG. 5 .
FIG. 7 is a front elevational, sectional view of a first alternative embodiment of the tool assembly of FIG. 1 .
FIG. 8 is a left side elevational view of the tool assembly of FIG. 7 .
FIG. 9 is a front elevational, sectional view of a second alternative embodiment of the tool assembly of FIG. 1 .
FIG. 10 a is a left side fragmentary, elevational view of the boom arm modified for use with a third alternative embodiment of the tool assembly of FIG. 1 showing only the rotary actuator thereof.
FIG. 10 b is a right side fragmentary, elevational view of the third alternative embodiment of the tool assembly mounted to the boom arm coaxial with the bucket.
FIG. 10 c is an enlarged, fragmentary, front view of the third alternative embodiment of the tool assembly shown in FIG. 10 b.
FIG. 11 a is a left side elevational view of the boom arm and a fourth alternative embodiment of the tool assembly of FIG. 1 also providing lateral tilting and rotation of the tool assembly relative to the plane swept out by the boom arm.
FIG. 11 b is a left side elevational view of the fourth alternative embodiment of the tool assembly of FIG. 11 a with the bucket rotated 90°.
FIG. 11 c is a left side elevational view of the fourth alternative embodiment of the tool assembly of FIG. 11 a with the bucket rotated 180°.
FIG. 11 d is a front elevational view of the fourth alternative embodiment of the tool assembly of FIG. 11 a with the bucket laterally tilted.
FIG. 11 e is a front elevational view of the fourth alternative embodiment of the tool assembly of FIG. 11 a in the rotational position of FIG. 11 b.
FIG. 11 f is a front elevational view of the fourth alternative embodiment of the tool assembly of FIG. 11 a in the rotational position of FIG. 11 b and with the bucket laterally tilted.
FIGS. 12 a and 12 b are left side elevational views of the boom arm and an alternative tool assembly embodying the present invention having first and second grapple members, with the first grapple member shown in various rotational positions relative to the boom arm and the second grapple member shown in various rotational positions relative to the first grapple member.
FIG. 13 is an enlarged, front elevational, sectional view of the alternative tool assembly of FIGS. 12 a and 12 b shown removed from the boom arm.
FIG. 14 is a left side elevational view of the alternative tool assembly of FIGS. 12 a and 12 b shown removed from the boom area.
FIG. 15 a is a front elevational view of the first grapple member of the alternative tool assembly of FIGS. 12 a and 12 b.
FIG. 15 b is a left side elevational view of the first grapple member of FIG. 15 a.
FIG. 15 c is a front elevational view of the second grapple member of the alternative tool assembly of FIGS. 12 a and 12 b.
FIG. 15 d is a left side elevational view of the second grapple member of FIG. 15 c.
FIG. 16 a is a left side elevational view of the boom arm and a first alternative embodiment of the alternative tool assembly of FIGS. 12 a and 12 b providing lateral tilting and rotation of the alternative tool assembly relative to the plane swept out by the boom arm.
FIG. 16 b is a front elevational view of the first alternative embodiment of the alternative tool assembly of FIG. 16 a with the tool assembly rotated 90°.
FIG. 16 c is a front elevational view of the first alternative embodiment of the alternative tool assembly of FIG. 16 a in the rotational position of FIG. 16 b and with the alternative tool assembly laterally tilted.
FIG. 17 is a left side elevational view of the boom arm and a second alternative embodiment of the alternative tool assembly of FIGS. 12 a and 12 b also providing lateral tilting and rotation to the alternative tool assembly relative to the plane swept out by the boom arm.
DETAILED DESCRIPTION OF THE INVENTION
As shown in the drawings for purposes of illustration, the present invention is embodied in a fluid-powered tool assembly, indicated generally by reference numeral 10 . As shown in FIG. 1, the tool assembly 10 is usable with a support platform shown as a vehicle 12 . The support platform may also be a stationary platform. The vehicle 12 has a first boom arm 14 which is pivotally connected by one end to a base member 16 . A pair of hydraulic cylinders 18 (only one being shown in FIG. 1) is provided for raising and lowering the first arm 14 in a generally vertical arm rotation plane with respect to the base member 16 . A second boom arm 20 is pivotally connected by one end to an end of the first arm 14 remote from base member 16 . A hydraulic cylinder 22 is provided for rotation of the second arm 20 relative to the first arm 14 in the same vertical arm rotation plane as the first arm operates.
The base member 16 is pivotally attached to the vehicle 12 for pivotal movement about a vertical axis so as to permit movement of the first and second arms 14 and 20 in unison to the left or right, with the first and second arms always being maintained in the arm rotation plane. It is noted that while the arm rotation plane is forwardly extending as shown in FIG. 1, as the base member 16 is pivoted the arm rotation plane turns about the vertical pivot axis of the base member and thus loses its forward-to rearward orientation, with the plane actually extending laterally should the base member be sufficiently rotated. When the tool assembly 10 is used by an excavator with a cab unit mounted by a turntable bearing to a tracked carriage, the cab and hence the arm rotation plane of the first and second arms 14 and 20 can rotate 360° relative to the carriage.
A rotation link 24 is pivotally connected through an interconnecting link 26 to an end portion 28 of the second arm 20 remote from the point of attachment of the second arm to the first arm 14 . A hydraulic cylinder 30 is provided for selective movement of the rotation link 24 relative to the second arm 20 .
As is conventional, a free end portion 31 of the second arm 20 and a free end portion 32 of the rotation link 24 each has a transverse aperture therethrough for connection of the second arm and the rotation link to a tool using selectively removable attachment pins 33 a and 33 b , respectively. The attachment pins 33 a and 33 b are insertable in the apertures to pivotally connect a conventional tool to the second arm and the rotation link. When using a conventional tool, this permits the tool to be rotated about the attachment pin 33 of the second arm 20 upon movement of the rotation link 24 relative to the second arm as a result of extension or retraction of the hydraulic cylinder 30 to rotate the tool in the arm rotation plane defined by the first and second arms 14 and 20 . A quick coupler or other mounting means may be used to connect the tool to the second arm 20 and the rotation link 24 . In an alternative embodiment not shown, the links 24 and 26 are not used and the hydraulic cylinder 30 is directly attached to the tool to be rotated.
As illustrated in FIG. 1, the tool assembly 10 comprises a first tool which in the case of the illustrated embodiment is a bucket 34 . The bucket 34 has a forward working edge 35 extending laterally, generally transverse to the arm rotation plane. The bucket 34 further includes a first clevis 36 and a second clevis 38 . The first clevis 36 is located toward the bucket working edge 35 and is attached to the free end portion 31 of the second arm 20 with the attachment pin 33 a . The second clevis 38 is located rearwardly away from the first clevis 36 and is attached to the free end portion 32 of the rotation link 24 with the attachment pin 33 b . The first and second devises 36 and 38 are in general parallel alignment with the arm rotation plane of the bucket 34 . It should be understood the present invention may be practiced using other tools as work implements, and is not limited to buckets or other collection tools and devices.
The tool assembly 10 also includes a second tool which in the case of the embodiment illustrated in FIG. 1 is a lid or bucket extension 39 . As part of the tool assembly 10 , both the bucket 34 and the bucket extension 39 are connected to a rotary actuator 40 for pivotal movement relative to each other. This allows for the bucket extension 39 to rotate relative to the bucket 34 about an axis of rotation 41 of the rotary actuator 40 (see FIG. 3 ). The rotary actuator 40 provides rotational torque which causes the bucket extension 39 to rotate about the axis 41 of the rotary actuator 40 relative to the bucket 34 .
FIGS. 2 a - 2 d illustrate four positions of the bucket 34 relative to the second arm 20 . In operation, the movement of the rotation link 24 relative to the second arm 20 causes the bucket 34 to be selectively rotated through the arm rotation plane about the attachment pin 33 a of the second arm 20 as the rotation link is moved relative to the second arm 20 by the hydraulic cylinder 30 . FIGS. 2 a and 2 c show the bucket 34 rotated in a fully counterclockwise position relative to the second arm 20 with the hydraulic cylinder 30 in a fully retracted state. FIG. 2 b shows the bucket 34 in a midway position relative to the second arm 20 with the hydraulic cylinder in a semi-extended state. FIG. 2 d shows the bucket 34 rotated in a fully clockwise position relative to the second arm 20 with the hydraulic cylinder 30 in a fully extended state.
FIGS. 2 a - 2 d also illustrate possible positions of the bucket extension 39 relative to the bucket 34 resulting from operation of the rotary actuator 40 causing the bucket extension to rotate about the axis 41 of the rotary actuator. The position of the bucket extension 39 relative to the bucket 34 produced by operation of the rotary actuator 40 is independent of the position of the bucket 34 relative to the second arm 20 produced by operation of the hydraulic cylinder 30 , although in certain positions of the bucket the presence of the second arm blocks full movement of the bucket extension through its full range of movement. FIG. 2 a shows the bucket extension 39 in a fully counterclockwise closed position relative to the bucket 34 . FIG. 2 c shows the bucket extension 39 in a fully clockwise open position relative to the bucket 34 . FIGS. 2 b and 2 d show the bucket extension 39 in a midway position relative to the bucket 34 with the bucket 34 and bucket extension grasping therebetween an object such as a large rock (FIG. 2 b ) or a culvert pipe (FIG. 2 d ). The bucket extension may also be selectively and delicately used to grasp chosen articles in cleanup or sorting processes.
The construction of the rotary actuator 40 is best shown in FIG. 3 . The rotary actuator 40 has an elongated housing or body 42 with a cylindrical sidewall 44 and first and second ends 46 and 48 , respectively. An elongated rotary drive or output shaft 50 is coaxially positioned within the body 42 and supported for rotation relative to the body 42 . The shaft 50 extends the full length of the body 42 , and has a flange portion 52 at the first body end 46 . The shaft 50 has an annular shaft nut 58 threadably attached thereto at the second body end 48 . The shaft nut 58 has a threaded interior portion threadably attached to a correspondingly threaded perimeter portion 60 of the shaft 50 and the shaft nut rotates with the shaft. The shaft nut 58 is generally locked in place against rotation relative to the shaft 50 .
Seals 62 are disposed between the shaft nut 58 and the shaft 50 , and between the shaft nut and the body sidewall 44 to provide a fluid-tight seal therebetween. Seals 64 are disposed between the shaft flange portion 52 and the body sidewall 44 to provide a fluid-tight seal therebetween. Radial bearings 66 and thrust bearings 68 are disposed between the shaft flange portion 52 and the body sidewall 44 , and between the shaft nut 58 and the body sidewall 44 to support the shaft 50 against radial and longitudinal thrust loads and to secure the shaft 50 in the body 42 .
The exterior end surfaces of the shaft flange portion 52 and the shaft nut 58 are flat and each have a plurality of apertures 70 and 72 , respectively, which threadably receive attachment bolts 74 (shown in FIGS. 2 a - 2 d ) to attach the bucket extension 39 to the shaft 50 for movement therewith relative to the body 42 . The first body end 46 also has a flange portion 76 with apertures 78 which receive attachment bolts 80 (shown in FIGS. 2 a - 2 d ) for attaching the body 42 of the rotary actuator 40 to the bucket 34 .
As shown in FIG. 3, an annular piston sleeve 82 is coaxially and reciprocally mounted within the body 42 coaxially about the shaft 50 . The piston sleeve 82 has outer splines, grooves or threads 84 over a portion of its length which mesh with inner splines, grooves or threads 86 of a splined intermediate interior ring gear portion 87 of the body sidewall 44 . The piston sleeve 82 is also provided with inner splines, grooves or threads 88 which mesh with outer splines, grooves or threads 90 provided on a portion of the shaft 50 toward the first body end 46 . It should be understood that while helical splines are shown in the drawings and described herein, the principle of the invention is equally applicable to any form of linear-to-rotary motion conversion means, such as balls or rollers. At least one pair of meshing splines, grooves or threads are helical to convert axial motion of the piston sleeve 82 to rotary motion of the shaft 50 . Alternatively, all the splines, grooves or threads can be helical and/or can be threaded in the same direction (e.g., left-handed or right-handed) or different directions, depending on the desired direction and amount of shaft rotation per unit of axial motion the piston sleeve 82 . It should be understood that while splines are shown in the drawings and described herein, the principle of the invention is equally applicable to any form of linear-to-rotary motion conversion arrangement, such as balls or rollers, and that the splines can include any type of groove or channel suitable for such motion conversion.
In the illustrated embodiment of the invention, the piston sleeve 82 has an annular piston head member 92 which has a threaded exterior portion 94 threadably attached to a second annular piston head member 96 by a correspondingly threaded interior portion 98 of the second annular piston head member 96 . The two piston head members 92 and 96 are thus joined to form a common piston head 99 . Seals 100 are disposed between the piston head member 92 and a smooth exterior wall shaft of the shaft 50 to provide a fluid-tight seal therebetween. Seals 102 are disposed between the piston head member 96 and the interior wall surface of the body-sidewall 44 to provide a fluid tight seal therebetween. A seal 104 is disposed between the piston head member 92 and piston head member 96 to provide a fluid tight seal therebetween.
As will be readily understood, reciprocation of the common piston head 99 within the body 42 occurs when hydraulic oil, air or any other suitable fluid under pressure selectively enters through one or the other of a first port P 1 which is in fluid communication with a fluid-tight compartment within the body to a side of the piston head toward the first body end 46 or through a second port P 2 which is in fluid communication with a fluid-tight compartment within the body to a side of the piston head toward the second body end 48 . As the piston head 99 and the piston sleeve 82 , of which the common piston head is a part, linearly reciprocates in an axial direction within the body 42 , the outer splines, grooves or threads 84 of the piston sleeve engage or mesh with the inner splines, grooves or threads 86 of the body sidewall 44 to cause rotation of the piston sleeve, where both the outer splines 84 and the inner splines 86 are helical. The linear and rotational movement of the piston sleeve 82 is transmitted through the inner splines, grooves or threads 88 of the piston sleeve to the outer splines, grooves or threads 90 of the shaft 50 to cause the shaft to rotate. The smooth wall surface of the shaft 50 and the smooth wall surface of the body sidewall 44 have sufficient axial length to accommodate the full end-to-end reciprocating stroke travel of the piston sleeve 82 within the body 42 . Longitudinal movement of the shaft 50 is restricted, thus most movement of the piston sleeve 82 is converted into rotational movement of the shaft 50 . Depending on the slope and direction of turn of the various splines, grooves or threads, there may be provided a multiplication of the rotary output of the shaft 50 and a high level of torque may also be provided.
The application of fluid pressure to the first port P 1 produces axial movement of the piston sleeve 82 toward the second body end 48 . The application of fluid pressure to the second body port P 2 produces axial movement of the piston sleeve 82 toward the body first end 46 . The rotary actuator 40 provides relative rotational movement between the body 42 and shaft 50 through the conversion of linear movement of the piston sleeve 82 into rotational movement of the shaft, in a manner well known in the art. The shaft 50 is selectively rotated by the application of fluid pressure, and the rotation is transmitted to the bucket extension 39 or other tool attached thereto through the flange portion 52 of the shaft 50 to selectively rotate the bucket extension about the axis 41 of the rotary actuator 40 relative to the bucket 34 . It is noted that operation of the rotary actuator 40 to move the bucket extension 39 relative to the bucket 34 is not only independent of the rotation of the bucket 34 relative to the second arm 20 by operation of the hydraulic cylinder 30 , but is also about the axis 41 which is different and spaced apart from the axis of rotation of the bucket about the attachment pin 33 a.
FIGS. 4-6 show the tool assembly 10 having an alternative manner of attaching the bucket 34 to the body 42 of the rotary actuator 40 . In particular, the opposing side walls 34 a and 34 b of the bucket 34 each have an aperture 34 c therein which receives a corresponding one of the first and second body ends 46 and 48 of the body 42 therein. The first and second body ends 46 and 48 are welded to the corresponding side walls 34 a and 34 b of the bucket 34 by welds W. Thus, the attachment apertures 78 in the flange portion 76 of the first body end are not necessary.
FIGS. 7 and 8 depict a first alternative embodiment of the tool assembly 10 in which the rotary actuator 40 is removably positioned within a support housing or tube 105 . In this embodiment, the flange portion 76 of the first body end 46 uses the attachment bolts 80 to attach the actuator body 42 to a flange portion 106 of the support tube 105 . The second body end 48 of the rotary actuator 40 is snugly received in the support tube 105 in engagement with a cylindrical wall 108 thereof, but is not attached thereto. This limits transverse movement of the second body end 48 during operation of the tool assembly 10 . The support tube 105 also allows the actuator 40 to be slidably received coaxially within the support tube and protected from damage by the cylindrical wall 108 of the support tube. The support tube 105 further adds structural rigidity to the assembly 10 . The rotary actuator 40 is slidably removable from the support tube 105 for servicing of the actuator. In this embodiment, the bucket side walls 34 a and 34 b are welded to the support tube 105 by welds W, rather than to the first and second body ends 46 and 48 .
FIG. 9 depicts a second alternative embodiment of the tool assembly 10 in which the rotary actuator 40 does not extend the entire length of the support tube 105 . Like the embodiment of FIGS. 7 and 8, in the embodiment of FIG. 9, the actuator body 42 is attached to the support tube 105 only at the first body end 46 of the actuator and is slidably received in the support tube with the second body end 48 snugly received by the cylindrical wall 108 . In an alternative design, to improve alignment, rather than bolting the bucket extension 39 to the shaft 50 , the shaft may be terminated with straight splines which project axially outward and drivingly engage corresponding straight splines of a recess in the bucket extension coaxially aligned with the shaft of the rotary actuator 40 . Because the rotary actuator 40 used in FIG. 9 is shorter than the bucket 34 is wide, the bucket extension 39 is not attached directly to the shaft nut 58 as in the previously described embodiments. Instead, a pivot pin 109 is used to rotatably mount the bucket extension 39 to an end plate 110 closing the end of the tube support 105 at the end opposite the end to which the flange portion 76 of the first body end 46 is attached. The pivot pin 109 provides an axis of rotation aligned with the axis 41 of the rotary actuator 40 .
A third alternative embodiment of the tool assembly 10 is shown in FIGS. 10 a - 10 c using a bucket lid 39 ′ instead of a bucket extension. In this embodiment the rotary actuator 40 is mounted to the second arm 20 in coaxial arrangement with the bucket 34 and the bucket lid 39 ′ for both rotation of the bucket relative to the second arm and rotation of the bucket lid relative to the bucket about the axis 41 of the rotary actuator. It is noted that with this arrangement the bucket lid 39 ′ is located laterally inward of the sidewalls 34 a and 34 b of the bucket 34 .
In this third alternative embodiment, the body 42 of the rotary actuator 40 has a pair of attachment flanges 43 by which the actuator body is securely attached to a pair of attachment flanges 21 projecting from the free end portion 31 of the second arm 20 . The attachment flanges 43 of the actuator body 42 and the attachment flanges 21 of the second arm 20 each have two transverse apertures therethrough. The one set of apertures of the attachment flanges 21 and 43 are aligned to accept a first pin 111 a and the other set of apertures of the attachment flanges 21 and 43 are aligned to accept a second pin 111 b to securely attach the rotary actuator 40 to the second arm 20 for movement therewith and to prevent rotation of the actuator body 42 relative to the second arm. To provide pivotal movement of the bucket 34 relative to the second arm 20 by operation of the hydraulic cylinder 30 using the links 24 and 26 , in the manner describe above, the attachment pin 33 a is rotatably received in an aperture 50 a extending longitudinally fully through the shaft 50 of the rotary actuator 40 . As before, the first clevis 36 of the bucket 34 receives the attachment pin 33 a for rotation of the bucket thereabout in response to operation of the hydraulic cylinder 30 . To facilitate independent rotation of the bucket 34 on the attachment pin 33 a from rotation of the shaft 50 of the rotary actuator 40 , the attachment pin 33 a is rotatably supported in the shaft aperture 50 a by bearings 50 b . To rotate the bucket lid 39 ′ relative to the second arm 20 attached to the actuator body 42 , and hence also the bucket 34 , the bucket lid is attached to the shaft flange portion 52 and shaft nut 58 of the shaft 50 , as described above, and rotates with the shaft in response to the linear reciprocation of the piston sleeve 82 . In this embodiment, the relative rotational movement of the bucket lid 39 ′ and the bucket 34 depends upon the operation of both the hydraulic actuator 30 and the rotary actuator 40 .
FIGS 11 a - 11 f show a fourth alternative embodiment of the tool assembly 10 which allows the bucket 34 , bucket extension 39 and rotary actuator 40 to be tilted and rotated relative to the arm rotation plane defined by the first and second arms 14 and 20 . The rotary actuator based tiltable feature is fully disclosed in U.S. Pat. No. 5,487,230, Tool Actuator With Adjustable Attachment Mount, which is incorporated herein in its entirety. The first and second celvises 36 and 38 are used to removably attach the rotary actuator 40 and bucket 34 to a turntable bearing assembly 113 . The turntable bearing assembly 113 is also attached to a rotary actuator assembly 112 having a rotary actuator constructed generally as described above for rotary actuator 40 and arranged transverse to the rotary actuator 40 . The rotary actuator assembly 112 has a pair of clevis 112 b which are attached to the free end portion 31 of the second arm 20 and to the free end portion 32 of the rotation link 24 .
The bucket 34 , bucket extension 39 and rotary actuator 40 can be selectively rotated or tilted about an axis of rotation 112 a of the rotary actuator assembly 112 and selectively rotated about an axis of rotation 113 a of the turntable bearing assembly 113 . The turntable bearing assembly 113 includes a turntable bearing with a first member 113 b thereof to which the tool assembly 10 is attached using the first and second devises 36 and 38 for rotation therewith. The first turntable member 113 b has a ring gear with internal teeth. A second turntable member 113 c rotatably supports the first turntable member 113 b therebelow and supports a hydraulic motor and brake unit 113 d with a bull gear drivingly engaging the ring gear to selectively rotate the first turntable member 113 b relative to the second turntable member 113 c when the hydraulic motor 113 d is powered. This provides 360° of continuous rotation.
The axis of rotation 112 a of the rotary actuator assembly 112 is transverse to the axis of rotation 41 of the rotary actuator 40 , and the axis of rotation 113 a of the turntable bearing assembly 113 is transverse to the axis of rotation 41 of the rotary actuator 40 . Further, the axis of rotation 112 a of the rotary actuator assembly 112 is transverse to the axis of rotation 113 a of the turntable bearing assembly 113 , to provide an orthogonal arrangement of axes of rotation 41 , 112 a and 113 a , and provide a degree of movement of the bucket 34 and bucket extension that significantly increases the efficiency and effectiveness of operation. The bucket 34 , bucket extension 39 and rotary actuator 40 are shown in the side view of FIG. 11 b rotated as a unit by 90° about the turntable bearing axis of rotation 113 a from the position shown in the side view of FIG. 11 a by operation of the turntable bearing assembly 113 . In the side view of FIG. 11 c the rotation is 180° from the position in FIG. 11 a . In the front view of FIG. 11 d , the bucket 34 , bucket extension 39 and rotary actuator 40 are shown in the same rotational position as shown in FIG. 11 a , but tilted laterally relative to the arm rotation plane by rotation about the rotational axis 112 a of the rotary actuator assembly 112 by operation of the rotary actuator assembly 112 .
In the front views of FIGS. 11 e and 11 f , the bucket 34 , bucket extension 39 and rotary actuator 40 are shown in the same rotational position as shown in FIG. 11 b , but in FIG. 11 f they are tilted laterally relative to the arm rotation plane by rotation about the rotational axis 112 a of the rotary actuator assembly 112 by operation of the rotary actuator assembly 112 .
FIGS. 12 a and 12 b show an alternative tool assembly 10 ′ which comprises a brush rake or grapple having a first grapple member 120 and an opposing second grapple member 122 . The first grapple member 120 is attached to the actuator body 42 by the attachment bolts 80 and the second grapple member 122 is attached to the shaft flange portion 52 by the attachment bolts 74 , much as described above for the embodiment of FIGS. 1-3. FIG. 12 a shows the tool assembly 10 ′ in a fully open position and FIG. 12 b shows the tool assembly in a closed position grasping a pipe. As viewed in FIGS. 12 a and 12 b , the rotary actuator 40 rotates the second grapple member 122 in a counterclockwise direction relative to the first grapple member 120 when moving from an open position (FIG. 12 a ) to a closed position (FIG. 12 b ).
FIGS. 13 and 14 illustrate the tool assembly 10 ′ of FIGS. 12 a and 12 b as having a similar construction to the tool assembly 10 of FIG. 7 with the rotary actuator 40 slidably received into the support tube 105 and with the several fingers comprising the first grapple member 120 fixedly attached to the support tube. Two of the fingers comprising the second grapple member 122 are attached to the shaft flange portion 52 and shaft nut 58 of the rotary actuator 40 by the attachment bolts 74 for rotation with the shaft 50 .
FIGS. 15 a and 15 b illustrate the first grappling member 120 as having four grappling prongs or fingers 128 and cross members 130 extending through transverse apertures 132 in the grappling fingers and fixedly attached thereto. FIGS. 15 c and 15 d illustrate the second grappling member 122 as having grappling prongs or fingers 134 and cross members 136 extending through transverse apertures 138 in the grappling fingers and fixedly attached thereto. Two of the fingers 134 each have at one end a flange 140 and are spaced about to receive the rotary actuator 40 therebetween. The flanges 140 are attached to the flange portion 52 and the shaft nut 58 of the shaft 50 by the attachment bolts 74 .
FIGS. 16 a - 16 c show a first alternative of the tool assembly 10 ′ of FIGS. 12 a and 12 b which allow the first and second grapple members 120 and 122 , and the rotary actuator 40 to be tilted and rotated relative to the arm rotation plane defined by the first and second arms 14 and 20 , much as in the embodiments of the tool assembly 10 shown in FIGS. 11 a - 11 f . As described above, the rotary actuator assembly 112 has a rotary actuator constructed generally as described above for rotary actuator 40 and is arranged transverse to the rotary actuator 40 . The first and second grapple members 120 and 122 and the rotary actuator 40 can be selectively rotated or tilted about the axis of rotation 112 a of the rotary assembly 112 and selectively rotated about the axis of rotation 113 a of the turntable bearing assembly 113 , as described above for the fourth alternative embodiment of the tool assembly 10 of FIGS. 11 a - 11 f . As described above, the rotary actuator 40 , the rotary actuator assembly 112 and the turntable bearing assembly 113 have an orthogonal arrangement of axes of rotation 41 , 112 a , and 113 a to provide a high degree of movement for the first and second grapple members 120 and 122 as a unit.
FIG. 17 shows a second alternative of the tool assembly 10 ′ of FIGS. 12 a and 12 b of a similar construction as shown in FIGS. 16 a - 16 c but with the first grapple member 120 and the rotary actuator 40 fixedly attached to the first turntable member 113 b whereas FIGS. 16 a - 16 c depict attachment using the devises 36 and 38 .
It will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.
All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety. | A tool assembly using a fluid-powered actuator and including first and second tool members. The first tool member is pivotably connectable to a boom arm of a vehicle or stationary support platform for rotation about a first axis. The first tool member is also attached to a body of the actuator and the second tool members is attached to a shaft of the actuator so that operation of the actuator rotates the second tool member relative to the first tool member about a second axis spaced apart from the first axis and independent of rotation of the first tool member about the first axis. The second tool member is positioned to cooperatively engage the first tool member to assist in collection operations. The actuator has a generally cylindrical body with an output shaft rotatably disposed therein for rotation about the second axis. A linear-to-rotary transmission device disposed within the actuator body produces selective rotational movement of the shaft relative to the body and hence the second tool member relative to the first tool member. As the actuator goes through a range of motion the tool assembly moves between fully open and fully closed positions. In one embodiment, the actuator body is disposed in and attached to a protective support tube having the first tool member attached thereto. Other embodiments have further rotation and tilting assemblies to provide three orthogonal axes of rotation. Another attaches the tool members so that the first and second axes are coaxial. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of priority from U.S. Provisional Application No. 60/943,397, filed Jun. 12, 2007, the disclosure of which is hereby incorporated in its entirety by reference thereto.
TECHNICAL FIELD
Embodiments of the present invention relate to syringe assemblies having a passive locking mechanism which restricts distal movement of the plunger rod after injection to prevent reuse, syringe assemblies wherein the stopper and plunger rod operate using relative motion to passively disable the syringe, syringe assemblies including a removeably connected stopper and plunger rod to prevent disassembly of the syringe prior to use and syringe assemblies including visual indication or markings to indicate use of the syringe or a disabled syringe.
BACKGROUND
Reuse of hypodermic syringe products without sterilization or sufficient sterilization is believed to perpetuate drug abuse and facilitate the transfer of contagious diseases. The reuse of syringes by intravenous drug users further exacerbates the transfer of contagious diseases because they comprise a high-risk group with respect to certain viruses such as the AIDS virus and hepatitis. A high risk of contamination also exists in countries with shortages of medical personnel and supplies.
A syringe which can be rendered inoperable after use presents a viable solution to these issues. Various syringes have been proposed and are commercially available that can be disabled by the user by taking active steps to disable the syringe. Single-use syringes that do not require the user to actively disable the syringe are also thought to offer a solution. It would be desirable to provide syringes that are automatically or passively disabled from reuse and can be manufactured in a cost-effective manner by, for example, utilizing fewer parts. Further, markings or other indicators which visually indicate whether a syringe has been used or is disabled would also be desirable.
SUMMARY
A passive disabling system for a syringe assembly that activates after completion of an injection cycle is provided. A syringe assembly incorporates a stopper and plunger rod attached in a manner to prevent users from disassembling the syringe prior to completion of the injection cycle. In one or more embodiments of the invention, a user can fill, inject and/or reconstitute medication.
In this disclosure, a convention is followed wherein the distal end of the device is the end closest to a patient and the proximal end of the device is the end away from the patient and closest to a practitioner.
A syringe assembly is provided which includes a barrel, an elongate plunger rod and stopper having respective structures and assembly which allow the user to passively lock the plunger rod within the barrel to prevent reuse of the syringe assembly. The barrel includes a distal end, an open proximal end, a cylindrical sidewall, which defines a chamber in which fluid may be held, and a distal wall. An opening in the distal wall permits fluid to flow from the chamber through the opening. In one embodiment, the barrel includes a marker or indicator which indicates whether the syringe has been disabled or the plunger has been locked within the barrel.
In one or more embodiments, the sidewall of the barrel has a continuous diameter or first inner diameter. As used throughout this application, the term “diameter” is a measurement of the longest distance between the walls of the barrel having any cross-sectional shape. However, it will be appreciated that conventional syringes are typically cylindrical with a circular cross-sectional shape. In accordance with some embodiments of the present invention, the barrel includes a rib, locking rib or other such impediment suitable for restricting the proximal movement of the plunger rod, adjacent to its proximal end. In one embodiment, the rib has a second inner diameter, wherein the second diameter is less than the first diameter. One or more embodiments of the present invention include an increased diameter region located proximally from the rib having a third inner diameter, wherein the third diameter is greater than the first diameter and second diameter. A diameter transition region having an axial length located between the rib and the increased diameter region may be included. The diameter transition region can have a varying inner diameter, which increases in the proximal direction.
Embodiments of the present invention also include an extended plunger rod which has a proximal end, a distal end, and a main body between the proximal and distal end. In some embodiments, the plunger rod slides or otherwise moves proximally and distally within the chamber of the barrel.
The distal end of the plunger can include a stopper-engaging portion having a distal and proximal end. The stopper-engaging portion provides a means for the stopper and plunger rod to move proximally and distally within the barrel. The stopper-engaging portion allows the stopper and plunger rod to move proximally and distally relative to each other. In a specific embodiment, the stopper-engaging portion may include a rim at its distal end, or a retainer or alternate means suitable for restraining the stopper.
The stopper-engaging portion according to one or more embodiments may also include a visual indicator or a visual display that indicates use of the syringe or whether the syringe is disabled.
The plunger rod can further include means for locking the plunger rod in the barrel to prevent reuse of the syringe assembly when the syringe is fully injected or “bottomed.” The means can have an outer diameter greater than the inner diameter of the barrel at the rib or the second inner diameter. As used herein, the term “bottomed” shall refer to the position of the syringe assembly wherein the stopper, while attached to the plunger rod, is in contact with the distal wall of the barrel and the plunger rod can no longer move in the distal direction.
One or more embodiments of the present invention utilize a protrusion, or annular protrusion that extends radially from the plunger rod. In some embodiments, the protrusion is located between the thumb press and the main body, as an example of a means for locking the plunger rod in the barrel. According to an embodiment of the invention, the protrusion is integrally molded to the plunger rod.
In one configuration, the protrusion has an outer diameter greater than the second inner diameter. Once the protrusion distally moves through the diameter transition region, past the rib and into the barrel, it becomes locked by the rib, thereby preventing proximal movement of the plunger rod. The protrusion of one embodiment is tapered or otherwise shaped in such a manner such that it may move in the distal direction past the rib more easily.
The plunger rod can further comprise at least one frangible portion for separating a portion of the plunger rod from the body. In this configuration, when a user attempts to reuse the syringe assembly or otherwise pull the plunger in the proximal direction out of the barrel, after the plunger rod has been locked, the plunger rod breaks at the frangible portion, leaving a portion of the plunger rod locked within the barrel. In a specific embodiment, the frangible portion is located between the protrusion and the thumb press.
The stopper has a proximal end and a distal end and the stopper is attached the stopper-engaging portion of the plunger rod. In some embodiments, the stopper moves distally and proximally within the barrel. The stopper also moves distally and proximally along a pre-selected axial distance relative to the stopper-engaging portion of the plunger rod, thereby allowing the protrusion to move distally past the rib into the locked position, when the syringe assembly is bottomed.
The stopper may further comprise a stopper body or stopper boss at the proximal end of the stopper. A peripheral lip may be included at the proximal end of the stopper body. A frangible connection may be provided to connect the stopper to the plunger rod, which may connect the stopper and the peripheral lip.
The stopper-engaging portion of the plunger rod and the stopper may be connected in a manner such that when the user applies a force in the proximal direction for aspiration or filling the syringe, the stopper remains stationary until plunger rod moves in the proximal direction the length of the pre-selected axial distance. In one embodiment, when a user continues to aspirate or fill the syringe assembly, the stopper begins to move in the proximal direction in tandem with the plunger rod, after the plunger rod has traveled the pre-selected axial distance in the proximal direction. An optional visual indicator or display disposed on the stopper-engaging portion of the plunger rod is visible when the user fills the syringe assembly.
In one or more embodiments of the present invention, when a user injects the contents of the syringe assembly, the attachment of the stopper and the stopper-engaging portion allow the plunger rod to move distally for a length of the pre-selected axial distance, while the stopper remains stationary. After the plunger rod travels distally for the length of the pre-selected axial distance, the stopper begins to move distally with the plunger rod. During such distal movement, where a visual indicator or display is utilized, the visual indicator or display disposed on the stopper-engaging portion of the plunger rod is no longer visible. Where a visual marker is utilized, the visual marker disposed on the barrel continues to be visible, even after the plunger rod is locked. As will be more fully described herein, the marker provides an alternative means of indicating the syringe has been disabled.
According to one embodiment of the present invention, the total length of the plunger rod is decreased by pre-selected axial distance when the stopper and plunger rod move together in the distal direction during injection of the contents of the syringe assembly. As such, the stopper and stopper-engaging portion of the syringe assembly are attached in a manner such that when a user has fully completed the injection cycle, the protrusion of the plunger rod advances past the rib of the barrel. In some embodiments, once the protrusion advances past the rib of the barrel, it locks the plunger rod within the barrel and prevents the user from reusing the syringe assembly or otherwise pulling the plunger rod out of the barrel. Once the plunger rod is locked within the barrel, the optional visual indicator or display on the stopper-engaging portion of the plunger rod is no longer visible, indicating the syringe has been disabled.
The syringe assembly may include one or more frangible portions of the plunger rod, which break when a user attempts to move the plunger rod in a proximal direction after the protrusion has advanced past the rib of the barrel. Other suitable means may be utilized for separating a portion of the plunger rod from the main body when the user applies sufficient proximal force to the plunger rod or otherwise attempts to reuse the syringe assembly after it is bottomed.
In accordance with one embodiment of the invention, the stopper and the stopper-engaging portion are attached in such a manner such that when a user attempts to disassemble the syringe assembly prior to aspiration, injection or bottoming, the stopper-engaging portion disengages from the stopper, leaving the stopper inside the barrel and allowing the separated plunger rod to be removed. In some embodiments, inner diameter of the barrel at the rib, or the second inner diameter, is less than the outer diameter of the stopper, and thereby prevents the stopper from moving proximally past the rib and causes the stopper-engaging portion to detach from the stopper, leaving the stopper inside the barrel. An optional frangible connection of the stopper breaks when a user attempts to disassemble the syringe assembly by applying a continuous force in the proximal direction to the plunger rod prior to aspiration, injection or bottoming.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a perspective view of a syringe assembly according to an embodiment of the invention shown;
FIG. 2 illustrates a disassembled perspective view of a syringe assembly according to an embodiment of the invention;
FIG. 3 shows a cross-sectional view of the barrel shown in FIG. 2 taken along line 3 - 3 ;
FIG. 4 is an enlarged view of a portion of the barrel shown in FIG. 3 ;
FIG. 5 is a cross-sectional view of the stopper shown in FIG. 2 taken along line 5 - 5 ;
FIG. 6 is a cross-sectional view of the plunger rod shown in FIG. 2 taken along line 6 - 6 ;
FIG. 7 is a cross-sectional view taken along line 7 - 7 of FIG. 1 ;
FIG. 8 is an illustration of FIG. 7 showing the plunger rod being moved in the proximal direction;
FIG. 9 is an illustration of FIG. 8 showing the plunger rod being moved in the distal direction;
FIG. 10 is an illustration of FIG. 9 showing the plunger rod in a locked position in the syringe barrel;
FIG. 11 is an enlarged view of a proximal portion of the assembly shown in FIG. 10 ;
FIG. 12 illustrates a perspective view of an embodiment of a syringe assembly having a visual marker disposed on the barrel;
FIG. 13 illustrates a disassembled perspective view of an embodiment of a syringe assembly visual indicators or markers disposed on the barrel and the stopper-engaging portion of the plunger rod;
FIG. 14 is a cross-sectional view taken along line 14 - 14 of FIG. 12 ;
FIG. 15 is an illustration of FIG. 14 showing the plunger rod in a locked position in the syringe barrel;
FIG. 16 is an enlarged view of a proximal portion of the assembly shown in FIG. 15 ;
FIG. 17 is an illustration of FIG. 10 showing a proximal portion of the plunger rod being broken from the syringe assembly after the plunger rod has been locked in the syringe barrel;
FIG. 18 is an illustration of FIG. 7 showing the plunger rod being moved in the proximal direction and the stopper disengaging from the plunger rod;
FIG. 19 a disassembled perspective view of a syringe assembly according to another embodiment of the invention;
FIG. 20 is a perspective view of the plunger rod shown in FIG. 19 ;
FIG. 21 is a side elevational view of the stopper shown in FIG. 19 ;
FIG. 22 is a cross-sectional view taken along line 22 - 22 of the syringe assembly shown in FIG. 19 ;
FIG. 23 is an illustration of FIG. 22 showing the plunger rod being moved in the proximal direction;
FIG. 24 is an illustration of FIG. 23 showing the plunger rod being moved in the distal direction;
FIG. 25 is an illustration of FIG. 24 showing the plunger rod in a locked position in the syringe barrel;
FIG. 26 is an illustration of FIG. 25 showing a proximal portion of the plunger rod being broken from the syringe assembly after the plunger rod has been locked in the barrel; and
FIG. 27 is an illustration of FIG. 22 showing the plunger rod being moved in the proximal direction and the stopper disengaging from the plunger rod.
DETAILED DESCRIPTION
Before describing several exemplary embodiments of the invention, it is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. The invention is capable of other embodiments and of being practiced or being carried out in various ways.
One aspect of the present invention provides for a syringe assembly including a barrel, plunger rod and stopper having individual features and construction which allow the user to passively lock the plunger rod within the barrel to prevent reuse of the syringe assembly.
FIG. 1 shows a syringe assembly 100 according to one or more embodiments. As shown in FIG. 2 , the syringe assembly includes a barrel 120 , a plunger rod 140 and a stopper 160 , arranged such that the proximal end 169 of stopper is attached to the distal end 141 of the plunger rod. The connected stopper 160 and plunger rod 140 are inserted into the proximal end 129 of the barrel 120 .
As best shown in the FIG. 3 , the barrel 120 has a cylindrical sidewall 110 with an interior surface 126 that defines a chamber 128 . In one embodiment, the chamber 128 holds the contents of the syringe assembly which may include medication in powdered or fluid form. The barrel 120 is shown as having an open proximal end 129 , a distal end 121 , and a distal wall 122 . The distal wall 122 has an opening 111 in fluid communication with the chamber 128 .
The sidewall 110 of the barrel 120 defines a chamber having a continuous inner diameter along the longitudinal axis of the syringe. Alternatively, the barrel can include a sidewall has an inner diameter, which decreases linearly from the proximal end to the distal end. It is to be understood that the configuration shown is merely exemplary, and the components can be different in shape and size than shown. For example, the barrel can have an exterior prism shape, while retaining a cylindrical interior shape. Alternatively, both the exterior and interior surfaces of the barrel can have non-circular cross-sectional shapes.
The syringe barrel 120 is shown as having a peripheral flange 124 attached at the proximal end 129 of the barrel 120 . The barrel 120 further includes a needle cannula 150 , having a lumen 153 attached to the opening 111 in the distal wall 122 of the barrel 120 . As is known in the art, attachment means 152 is provided for attaching the needle cannula 150 to the distal wall 122 . The assembly 100 may also include a protective cap over the needle cannula (not shown).
As shown more clearly in FIG. 4 , the barrel 120 further includes a rib 123 adjacent its proximal end 129 . The inner diameter of the barrel at the location of the rib 123 is smaller than the inner diameter of the barrel 120 at other locations along the length of the barrel. One or more optional tabs or detents can be used to create a region of the barrel having a diameter smaller than the inner diameter of the barrel 120 . In a specific embodiment, the rib can include a ring formed along entire circumference of the interior surface 126 or a portion of the interior surface 126 of the inner diameter of the barrel 120 (not shown). The barrel 120 also includes a diameter transition region 127 adjacent to the rib 123 at the proximal end 129 of the barrel 120 . The inner diameter of the barrel at the diameter transition region 127 increases from the distal end 121 to the proximal end 129 of the barrel 120 . In the embodiment shown, the barrel includes an increased diameter region 125 adjacent to the diameter transition region at the proximal end 129 of the barrel. The inner diameter of the barrel 120 at the increased diameter region 125 is greater than the inner diameter of the barrel of the entire diameter transition region 127 .
The barrel may be made of plastic, glass or other suitable material. The barrel further includes optional dosage measurement indicia (not shown).
Referring now to FIG. 5 , the stopper 160 has a distal end 161 , a proximal end 169 , a stopper body 164 and a peripheral edge 162 which forms a seal with the interior surface 126 of the barrel. In one or more embodiments, the peripheral edge 162 of the stopper 160 has a larger diameter than the diameter of the interior surface of the rib 123 . The stopper 160 shown in FIG. 5 includes an optional elongate tip 166 on its distal end 161 to facilitate reduction of the residual fluid and expulsion of fluid from the syringe barrel.
The stopper 160 is shown as further having a tapered portion 165 adjacent to the stopper body 164 at its proximal end 169 . A neck 163 is adjacent to the tapered portion 165 at the proximal end 169 of the stopper 160 . The stopper body 164 is shown as also including an interior recess 168 , which allows the stopper-engaging portion 146 of the plunger rod 140 to connect to the stopper 160 . A peripheral rim 147 may be provided to help retain the stopper 160 on the plunger rod 140 . As with the rib of the barrel, detents or tabs can be used to retain the stopper 160 on the plunger rod 140 .
The stopper is typically made of plastic or other easily disposable and/or recyclable material. It may be desirable to incorporate natural or synthetic rubber in the stopper or use a natural or synthetic rubber seal with the stopper. It will be understood that the stopper may incorporate multiple seals.
Referring now to FIG. 6 , the syringe assembly includes a plunger rod 140 having a proximal end 149 , a distal end 141 , and a main body 148 extending between the proximal end 149 and distal end 141 . The plunger rod 140 further includes a thumb press 142 at the proximal end 149 of the plunger rod 140 . In the embodiment shown, the thumb press 142 further includes a textured surface, writeable surface and/or label.
Still referring to FIG. 6 , the plunger rod 140 further includes a protrusion 144 shown as an annular protrusion 144 between the thumb press 142 and the main body 148 . The outer diameter of the plunger rod at the protrusion 144 is greater than the inner diameter of the barrel 120 at the rib 123 . In some embodiments of the invention, the protrusion 144 includes a tapered portion 145 that facilitates distal movement of the protrusion past the rib 123 and into the barrel 120 , as will become apparent in the subsequent discussion of operation of the syringe. In at least one embodiment, the syringe assembly is configured to allow the protrusion 144 to advance distally past the rib 123 , to lock the plunger rod in the barrel when the user bottoms out the plunger rod in the barrel (as more clearly shown in FIGS. 10-11 ). In certain embodiments, the plunger rod 140 further includes at least one frangible connection or point 143 for separating at least a portion of the plunger rod from the main body when a user applies sufficient proximal force to the plunger rod after it has been locked. In the embodiment shown, the frangible point 143 is located between the protrusion 144 and the thumb press 142 . It will be understood that the frangible connection or point 143 shown is exemplary, and other suitable means for permanently damaging the plunger rod or otherwise separating at least a portion of the plunger rod from the main body may be provided.
In the embodiment shown, the stopper 160 is permitted to move distally and proximally within the barrel when connected to the stopper-engaging portion 146 of the plunger rod 140 . As will be understood better with the description of operation of the syringe assembly and with reference to FIG. 7 , the stopper is capable of moving distally and proximally a pre-selected axial distance 132 relative to the stopper-engaging portion.
The plunger rod may be made of plastic or other suitable material. The protrusion may also be comprised of plastic or a harder material suitable for locking the plunger rod within the barrel.
In FIG. 7 , the barrel 120 holds the stopper 160 and plunger rod 140 in the chamber, wherein the stopper is bottomed, “parked” or is in contact with the distal wall 122 of the barrel 120 . The peripheral edge of the stopper 162 forms a seal with the interior surface 126 of the barrel 120 . In one embodiment, the stopper 160 is connected to the stopper-engaging portion 146 of the plunger rod 140 . The stopper-engaging portion 146 is removeably held in the recess 168 of the stopper body 164 by the neck 163 .
In FIG. 7 , a gap between stopper 160 and the distal end of the main body 148 defines a pre-selected axial distance 132 prior to the injection cycle. In at least one embodiment, the protrusion 144 remains on the proximal side of the rib 123 because the length of the plunger rod 140 and stopper combined, along with the pre-selected axial distance 132 , is greater than the length of the barrel 120 from the distal wall 122 to the proximal end of the barrel 120 . The distance between the protrusion 144 and the peripheral edge 162 of the stopper body 164 defines a first distance, D 1 .
FIG. 8 illustrates the syringe assembly in use and specifically shows an aspiration or filling step, according to one or more embodiments of the present invention. When the user applies a force to the plunger rod 140 in the proximal direction shown by the arrow in FIG. 8 , the plunger rod 140 and the stopper 160 move together in the proximal direction, while the stopper-engaging portion 146 is connected to the stopper 160 by the rim 147 . In one or more embodiments, the gap defining the pre-selected axial distance 132 is maintained while the stopper 160 and plunger rod 140 move together in the proximal direction along the interior surface of the syringe barrel. The user terminates the application of proximal force on the plunger rod 140 once the desired amount of medicament is drawn into the syringe. During the aspiration step, the plunger rod and the stopper body move in the proximal direction together to draw medication into the syringe, while maintaining the first distance D 1 .
FIG. 9 also shows the syringe assembly in use and specifically demonstrates application of distal force to the plunger rod during injection. In one embodiment, when the user applies a force in the distal direction to the plunger rod 140 as indicated by the arrow, the plunger rod 140 moves in a distal direction for the length of the gap defining the pre-selected axial distance 132 in FIG. 7 , while the stopper 160 remains stationary. The stopper 160 remains stationary because the frictional force created by the peripheral edge 162 of the stopper on the interior surface 126 of the barrel is greater than the frictional force created by the stopper-engaging portion 146 entering the recess 168 of the stopper 160 . Consistent with at least one embodiment, once the stopper-engaging portion has distally moved the length of the pre-selected axial distance 132 and is in contact with the proximal end of the recess 169 , the stopper 160 and the plunger rod 140 begin to move in tandem in the distal direction. Further, the force applied by the user is greater than the friction between the peripheral edge 162 of the stopper 160 and the interior surface 126 of the barrel, and therefore the stopper 160 is forced to move in the distal direction with the plunger rod 140 . In one embodiment, the user may inject a limited amount of the fluid aspirated or exert a limited force on the plunger rod in the distal direction to flush or expel some of the aspirated fluid, without locking the plunger rod, provided that the syringe assembly is not bottomed. However, as will be described further with respect to FIG. 10 , a user may bottom the stopper against the distal wall of the syringe barrel, locking the plunger rod in the barrel.
When expelling the contents of the syringe, the plunger rod moves in a distal direction the length of the pre-selected axial distance 132 shown in FIG. 7 while the stopper body remains stationary, consequently closing the gap defining the pres-selected axial distance 132 . After the contents of the syringe have been fully expelled, the distance between the protrusion 144 and the peripheral edge 162 defines a second distance, D 2 , wherein D 2 is the difference between the first distance, D 1 , and the gap defining a pre-selected axial distance 132 .
FIG. 10 illustrates an embodiment of the syringe assembly after the plunger rod has been locked inside the barrel. In one or more embodiments, the entry of the stopper-engaging portion into the recess 168 of the stopper 160 (as also shown in FIG. 9 ) closes the gap defining the pre-selected axial distance 132 , allowing the protrusion 144 to advance past the locking rib 123 (as more clearly shown in FIG. 11 ). The protrusion 144 has an outer diameter greater than the inner diameter of the barrel at the rib 123 . Accordingly, in one or more embodiments, the rib 123 locks the protrusion 144 inside the barrel 120 , and prevents proximal movement of the plunger rod 140 .
FIG. 12 shows a syringe assembly 100 in which the barrel 120 includes a visual marker 300 . The marker is aligned with the rib 123 , as more clearly shown in FIG. 16 . The marker can be integrally formed on the sidewall of the barrel or can be added to the exterior surface of the sidewall. The marker can be printed in ink, adhesively applied, a textured surface or a separate piece that is fixed around the syringe barrel. The marker can form a ring around the circumference of the side wall or be in the form of tabs disposed at regular intervals around the circumference of the side wall. In a specific embodiment, the marker is a colored stripe. In a more specific embodiment, the marker can include text in the form of one or more letters and/or numbers, geometric shapes, symbols or combinations thereof to inform users the syringe is disabled.
FIG. 13 shows a plunger rod 140 having a visual indicator or display 310 disposed on the stopper-engaging portion 146 . As with the visual marker 300 , the visual indicator 310 can be integrally formed with the stopper-engaging portion of the plunger rod or be added to the exterior surface thereof. The indicator or display can be printed in ink, adhesively applied, a textured surface or a separate piece that is fixed to the stopper engaging portion. In one or more embodiments, the indicator or display can comprise a pattern, a solid portion and or can cover the entire surface of the stopper-engaging portion. In a specific embodiment, the indicator is a colored stripe disposed along the length of the stopper-engaging portion 146 between the distal end 141 and the main body 148 of the plunger rod. In a more specific embodiment, the indicator is a colored stripe disposed along the circumference of the stopper-engaging portion 146 of the plunger rod. In an even more specific embodiment, the marker can include text in the form of one or more letters and/or numbers, geometric shapes, symbols or combinations thereof.
As more clearly shown in FIG. 14 a gap between stopper 160 and the distal end of the main body 148 defines a pre-selected axial distance 132 prior to the injection cycle. The visual indicator 310 is visible when the gap is present. The visual marker 300 is disposed on the exterior surface of the barrel 120 and aligned with the rib 123 . As described with reference to FIG. 8 , when the user applies a force to the plunger rod 140 in the proximal direction shown by the arrow in FIG. 8 , the plunger rod 140 and the stopper 160 move together in the proximal direction, while the stopper-engaging portion 146 is connected to the stopper 160 by the rim 147 . In one or more embodiments, the gap defining the pre-selected axial distance 132 is maintained while the stopper 160 and plunger rod 140 move together in the proximal direction along the interior surface of the syringe barrel. Accordingly, the visual indicator 310 continues to be visible.
As described with reference to FIG. 9 , when expelling the contents of the syringe, the plunger rod moves in a distal direction the length of the pre-selected axial distance 132 shown in FIGS. 7 and 14 while the stopper body remains stationary, consequently closing the gap defining the pre-selected axial distance 132 . The movement of the stopper-engaging portion, in the distal direction relative to the stopper allows the stopper-engaging portion 146 of the plunger rod to move into the recess 168 of the stopper (as shown in FIG. 9 ). As can be more clearly seen in FIG. 15 , this relative movement allows the stopper body 164 covers the stopper-engaging portion and blocks visibility of the visual indicator 310 .
As more clearly shown in FIGS. 15 and 16 , the visual marker 300 disposed on the barrel 120 and aligned with the rib 123 also shows advancement of the protrusion 144 past the rib 123 . In addition, the entry of the stopper-engaging portion into the recess 168 of the stopper 160 (as also shown in FIG. 9 ) also closes the gap defining the pre-selected axial distance 132 , allowing the protrusion 144 to advance past the rib 123 (as more clearly shown in FIGS. 11 and 16 ). The location of the protrusion relative to the visual marker indicates whether the plunger rod has been locked within the barrel and the syringe assembly has been disabled. Before the plunger rod is locked, the protrusion 144 is proximally adjacent to the visual marker 300 . Once the plunger rod is locked, the protrusion 144 is distally adjacent to the visual marker 300 .
It will be appreciated that each of the visual marker 300 and the visual indicator 310 can be used alone or in combination.
FIG. 17 shows the assembly after the plunger rod 140 has been locked in the barrel 120 . An attempt to reuse the syringe assembly by applying a force to the plunger rod 140 in the proximal direction causes a portion of the plunger rod 140 to separate at the frangible connection or point 143 . The frangible connection or point 143 is designed so that the force holding exerted on the protrusion by the locking rib 123 while proximal force is being applied to the plunger rod 140 is greater than the force needed to break the plunger rod at the frangible point 143 and, therefore, the frangible point breaks or separates before the user is able to overcome the force exerted on the protrusion by the rib.
FIG. 18 shows the syringe assembly in a configuration in which the stopper 160 has separated from the stopper-engaging portion 146 . According to one or more embodiments of the invention, the stopper 160 and stopper-engaging portion 146 disengage to prevent a user from disassembling the parts of the syringe assembly prior to use. As otherwise described in reference to FIG. 5 , the peripheral edge 162 of the stopper 160 has a diameter greater than the diameter of the interior surface of the rib 123 . Consistent with at least one embodiment of the invention, when a user applies a force to the plunger rod 140 in the proximal direction, the rib 123 locks the peripheral edge 162 of the stopper 160 , and the rim 147 of the stopper-engaging portion 146 disconnects from the neck 163 of the stopper. The rib 123 exerts a greater force on the peripheral edge of the stopper than the force or friction exerted by the rim of the stopper-engaging portion of the plunger rod and neck portion of the stopper while proximal force is applied to the plunger rod.
FIG. 19 shows an example of a syringe assembly according to another embodiment of the present invention. In the embodiment shown in FIG. 19 , the assembly includes a barrel 220 , a plunger rod 240 and a stopper 260 , arranged so that the proximal end of stopper 269 is attached to the distal end of the plunger rod 241 . The stopper 260 then plunger rod 240 is inserted into the proximal end of the barrel 229 . A flange 224 is attached at the proximal end 229 of the barrel 220 . The barrel 220 further includes a needle cannula 250 having a lumen 253 , attached to the opening in the distal wall 222 at the distal end 221 of the barrel 220 . One or more embodiments also include an attachment hub 252 for attaching the needle cannula 250 to the distal wall 222 . The assembly may also include a protective cap over the needle cannula (not shown).
Similar to the barrel illustrated previously in FIGS. 3 and 4 , and as shown in FIG. 22 , the barrel further include a rib 223 , locking rib or other means for locking the plunger rod within the barrel, having an interior surface with a smaller diameter than the diameter of the interior surface of the barrel.
Referring now to FIG. 20 , a perspective view of a plunger rod 240 is shown as having a main body 248 , a distal end 241 and a proximal end 249 . The plunger rod 240 further includes a thumb press 242 at its proximal end and a stopper-engaging portion 246 at its distal end. Plunger rod 240 also includes a protrusion in the form of an annular protrusion 244 between the thumb press 242 and the main body 248 . The protrusion 244 may include a tapered portion 245 to facilitate distal movement of the protrusion 244 past the rib 223 into the barrel 220 . In some embodiments, the protrusion 244 has an outer diameter greater than the inner diameter of the barrel at the rib 223 . In at least one embodiment, the configuration of the syringe assembly allows for the protrusion 244 to advance distally past the rib 223 , to lock the plunger rod 240 in the barrel 220 , when the user bottoms the syringe assembly (as more clearly shown in FIGS. 25-26 and discussed further below).
The plunger rod 240 shown further includes at least one frangible point 243 . In the embodiment shown, the frangible point 243 of the plunger rod 240 is located between the protrusion 244 and the thumb press 242 , but the frangible point could be in another location. A stopper-engaging portion 246 is included on the distal end 241 of the plunger rod 240 . As shown, the stopper-engaging portion 246 also includes a plunger recess and a retainer 247 . At least one embodiment of the invention includes a press-fit attachment or other suitable means for retaining the end of the stopper.
Referring now to FIG. 21 , which shows an embodiment of the stopper 260 having a distal end 261 and a proximal end 269 . According to at least one embodiment, the stopper 260 includes a peripheral edge 262 which forms a seal with the interior wall of the barrel 220 and has a diameter greater than the diameter of the interior surface of the barrel at the location of the rib 223 (as more clearly shown in FIGS. 22-24 ). As shown, an elongate tip 266 is provided at the distal end 261 of the stopper 260 to help expel the entire contents of the syringe. The stopper 220 can further include a stopper body 264 having a peripheral lip 263 at its proximal end 269 , according to at least one embodiment of the invention. Further, the stopper 260 can include a stopper frangible connection 265 connecting the stopper body 264 to the stopper 260 .
In this configuration, the stopper 260 and plunger rod 240 occupy the chamber of the barrel 220 and the stopper is bottomed against the distal wall of the barrel. Further, the peripheral edge 262 of the stopper 260 forms a seal with the interior surface of the barrel 220 . The stopper 260 is connected to the stopper-engaging portion 246 of the plunger rod 240 . As shown, the retainer 247 of the stopper-engaging portion 246 retains the peripheral lip 263 of the stopper 260 .
Embodiments of the syringe assembly of FIGS. 19-27 can also include a visual marker 300 , visual indicator 310 or both, as described with reference to FIGS. 13-16 . In a specific embodiment, the barrel 220 of one or more embodiments can also include a visual marker aligned with the locking rib 223 . In a more specific embodiment, the syringe assembly can include a visual indicator disposed on the stopper body 264 .
According to one or more embodiments, there is a gap between the stopper 260 and the distal end of the main body 248 defining a pre-selected axial distance 232 . In one or more embodiments, the distance between the protrusion 244 and the peripheral edge 262 of the stopper 260 defines a first distance, D 1 .
FIG. 23 illustrates the syringe assembly in use and specifically shows movement of the plunger rod during an aspiration or filling step according to one or more embodiments of the present invention. When the user applies a force to the plunger rod in the proximal direction, the plunger rod 240 and the stopper 260 move together in the proximal direction as indicated by the arrow, while the stopper-engaging portion 246 is connected to the stopper 260 by the rim 263 . In this configuration, the gap defining the pre-selected axial distance 232 is maintained while the stopper 260 and plunger rod 240 move together in the proximal direction. The user applies proximal force to the plunger rod until a predetermined or desired amount of medicament is aspirated or drawn into the syringe. During the aspiration step, the plunger rod and the stopper body move in the proximal direction together to draw medication into the syringe, while maintaining the first distance D 1 .
FIG. 24 also shows the syringe assembly when distal force is applied to the plunger rod during an injection step according to at least one embodiment of the present invention. Application of a force in the distal direction closing the gap and moving the pre-selected axial distance 232 shown in FIG. 22 , while the stopper 260 remains stationary. Consistent with at least one embodiment, once the stopper-engaging portion 246 has distally moved the pre-selected axial distance 232 and is in contact with stopper frangible connection 265 , the stopper 260 and the plunger rod 240 begin to move in tandem in the distal direction.
When expelling the contents of the syringe, the plunger rod moves in a distal direction the length of the pre-selected axial distance 232 while the stopper body remains stationary. During and after the contents of the syringe have begun to be or have been fully expelled, the distance between the protrusion 244 and the peripheral edge 262 defines a second distance, D 2 , wherein D 2 is the difference between the first distance, D 1 , and the gap defining a pre-selected axial distance 232 .
In one embodiment, the user may inject a limited amount of the fluid aspirated or exert a limited force on the plunger rod in the distal direction to flush or expel some of the aspirated fluid, without locking the plunger rod, provided that the syringe assembly is not bottomed. However, as will be described further below, a user will typically expel substantially all of the contents of the syringe by bottoming the stopper on the distal wall of the barrel.
Referring now to FIG. 25 , which illustrates the syringe assembly after the plunger rod 240 has been locked inside the barrel 220 , the distal movement of the stopper-engaging portion 246 to the stopper frangible connection 265 of the stopper 260 (as also shown in FIG. 24 ) closes the gap defining the pre-selected axial distance and allows the protrusion 244 to advance past the rib 223 , thereby locking the plunger rod 240 inside the barrel 220 , preventing re-use of the syringe assembly.
Referring now to FIG. 26 , the syringe assembly is shown in a configuration in which a user attempts to reuse the syringe assembly after the plunger rod 240 is locked inside the barrel 220 by applying a force to the plunger rod 240 in the proximal direction. Application of sufficient proximal force to the plunger rod causing a portion of the plunger rod 240 to separate at the frangible connection or point 243 , as the holding force of the protrusion 244 and the rib exceeds the breaking force of the frangible point or connection.
FIG. 27 shows the syringe assembly in a configuration after which proximal force has been applied to the plunger rod and the stopper has moved to the proximal end of the barrel. As shown in FIG. 27 , the stopper 260 has separated from the stopper-engaging portion 246 of the plunger rod. The stopper frangible connection 265 breaks to prevent a user from disassembling the parts of the syringe assembly. As otherwise described herein, the peripheral edge of the stopper 262 has an outer diameter greater than the inner diameter of the interior surface of the barrel at the location of the rib 223 . Consistent with at least one embodiment of the invention, when a user applies a force to the plunger rod 240 in the proximal direction, the rib 223 of the barrel 220 locks the peripheral edge 262 of the stopper 260 , and the stopper frangible connection 265 breaks, separating the stopper body 264 from the stopper 260 . Without being limited by theory, it is believed that the force required to break the frangible connection is less than the force exerted on the peripheral edge of the stopper.
According to one or more embodiments, the syringe barrel may include identifying information on the syringe assembly. Such information can include, but is not limited to one or more of identifying information regarding the contents of the syringe assembly or information regarding the intended recipient.
Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents. | Syringe assemblies having a passive disabling system to prevent reuse are provided. According to one or more embodiments, the syringe assembly comprises a barrel, plunger rod and stopper wherein the plunger rod further comprises a locking protrusion that locks the plunger rod within the barrel. Certain embodiments further include a frangible portion on the plunger rod that breaks when reuse is attempted. One or more embodiments include a plunger rod and stopper attachment that prevents disassembly of the syringe assembly prior to use. Syringe assemblies of one or more embodiments also include visual indicators or markers indicating whether a syringe assembly is used or the plunger rod is locked within the barrel. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to indoor games and, more particularly, to a game of chance that simulates the play of a round of golf.
BACKGROUND OF THE INVENTION
[0002] The game of golf is enormously popular world wide. There is often a desire on the part of golfers and fans of golf to simulate the play of golf in an indoor setting. Computerized golf games are an example of this phenomenon.
[0003] The present invention is directed to an indoor golf game that is simple to use, portable, and low-tech.
SUMMARY OF THE INVENTION
[0004] In accordance with one embodiment of the present invention, a golf game is provided. The game comprises, in combination: a rollable game piece having a plurality of flat sides therearound; and information relevant to the play of a round of golf located on the plurality of flat sides.
[0005] In accordance with another embodiment of the present invention, a golf game is provided. The game comprises, in combination: a rollable game piece having a plurality of flat sides therearound; information relevant to the play of a round of golf located on the plurality of flat sides; a scorecard; wherein the game piece is hollow and wherein the scorecard may be stored therein; and a writing implement utilizable with the scorecard and storable within the hollow game piece; wherein the information is organized into a plurality of bands arranged side-by-side along the game piece, and wherein each the band contains a different type of information relevant to the play of golf; wherein one the band contains information relevant to the play of a par 3 golf hole; wherein one the band contains information relevant to the play of a par 4 golf hole; wherein one the band contains information relevant to the play of a par 5 golf hole; wherein one the band contains information relevant to weather conditions; wherein one the band contains information relevant to hazards; wherein one the band contains information relevant to club selection; and wherein one the band contains information relevant to risks and rewards.
[0006] In accordance with still another embodiment of the present invention, a method for playing a golf game is disclosed. The method comprises the steps of: providing a rollable game piece having a plurality of flat sides therearound; providing information relevant to the play of a round of golf on the plurality of flat sides; rolling the game piece; and recording a score for a golf hole based on the information displayed on one of the plurality of flat sides.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a side view of a game piece portion of a golf game consistent with an embodiment of the present invention.
[0008] FIG. 1A is a perspective view of a cap for the game piece of FIG. 1 .
[0009] FIG. 1B is an end view of the game piece of FIG. 1 , showing the end opposite the capped end.
[0010] FIG. 1C is a perspective view of a game piece consistent with an embodiment of the present invention
[0011] FIG. 1D is a perspective view of a game piece consistent with an embodiment of the present invention.
[0012] FIG. 2 is a top view of a scorecard component of a golf game consistent with an embodiment of the present invention.
[0013] FIG. 3 is a perspective view illustrating the rolling of a game piece consistent with an embodiment of the present invention.
[0014] FIG. 4 is an exemplary set of game instructions for a golf game consistent with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Referring first to FIGS. 1-1D , a game piece 10 consistent with an embodiment of the present invention is depicted. It can be seen that the game piece 10 preferably has an elongated, cylindrical configuration, with a plurality of flat surfaces 12 extending the length thereof. As herein described, information relevant to the play of the golf game is presented on the flat surfaces 12 . The flat surfaces 12 should have sufficient width so that, upon rolling of the game piece 10 (see FIG. 3 ), it will come to rest with one flat surface 12 flush against the surface (e.g., a table or floor) upon which the game is being played, with an opposing flat surface 12 being substantially parallel thereto, being readily viewable by players, and being identifiable by the players as the flat surface 12 that has been produced as a result of the rolling of the game piece 10 .
[0016] Referring now to FIGS. 1C and 1D , examples of the type of information that may be presented on the flat surfaces 12 of the game piece 10 are provided. It can be seen that, in the preferred embodiment, the information is organized into seven columns or bands 14 . While the order, number and content of the columns can be varied without departing from the spirit or scope of the present invention, it is preferred that the columns be arranged in the following order and that they have the following general content, moving from left to right in the drawing figures: (a) club; (b) par 3; (c) hazard; (d) par 4; (e) weather; (f) par 5; and (g) risk/reward.
[0017] Referring now to FIG. 2 , an embodiment of a scorecard 20 is shown. The scorecard 20 is, preferably, an integral component of the golf game of the present invention. As can be seen in FIG. 2 , it is preferred that the scorecard 20 have the appearance of a traditional scorecard of the type used in the play of live golf at a golf course. Indeed, it may be desired to utilize a scorecard 20 corresponding to a particularly well-known actual golf course, such as Augusta National or St. Andrews. It may be desired to provide with the golf game a plurality of scorecards 20 , so as to add variety.
[0018] Referring now to FIGS. 1-1A , it can be seen that the game piece 10 is preferably hollow, and preferably has a cap 16 at one end thereof. The length of the game piece 10 should be sufficient to accommodate the insertion of a rolled-up scorecard 20 , as shown in FIG. 1 . Also, preferably, a marker 18 should be capable of being inserted therein, also as shown in FIG. 1 . While the game piece 10 need not be hollow and while these other game components could be provided separately, the configuration shown in FIG. 1 is advantageous because it enhances the portability and convenience of the game.
[0019] Preferably, the marker 18 is of the dry erase type, and the scorecard 20 has a surface that permits the permits the erasable use of a dry erase marker thereon, so that the scorecard 20 can be re-used.
[0020] Preferably, a set of game instructions, such as those shown in FIG. 4 , are also provided as part of the golf game. Preferably, these are printed on the reverse side of the scorecard 20 , so that they too can be retained within the game piece 10 when the game is not being played.
STATEMENT OF OPERATION
[0021] A golf game utilizing different embodiments of the game components described herein can take a variety of forms. An exemplary set of rules describing different game versions is provided in FIG. 4 , and incorporated herein by reference.
[0022] In one version, referred to in the rules as the “Duffers Game,” players take turn rolling the game piece 10 . In this version, players only pay attention to the second, fourth and sixth columns shown in FIGS. 1C-1D ; i.e., those columns concerning the score on a par 3, par 4, or par 5 hole. Each player, after rolling, is permitted to select the best of the three displayed scores, to the extent that there is an unplayed hole on the scorecard having that hole value. For example, if player one rolls the game piece 10 and the flat surface 12 that comes out on top shows a par on a par 3 hole, a par on a par 4 hole, and a birdie on a par 5 hole, the player will want to select the birdie on the par 5 hole, and he/she may write in that score on any par 5 hole that has not yet been filled in. In other words, the players can play the holes out of order.
[0023] It can be seen that it may be desired to provide a simplified game piece 10 having only three columns, with scores for par 3, par 4 and par 5 holes. (Indeed, if the game piece 10 is to be used to simulate the play of an executive type golf course, two columns, with scores for par 3 and par 4 holes, may be sufficient.) It may desired to provide a set of game pieces 10 of varying column number and complexity suitable for the play of different variations of the golf game of the present invention.
[0024] In another version of the game, called Mulligan play in the exemplary instructions, the same columns used in the play of the Duffers game are also the only columns used. What distinguishes Mulligan play from the Duffers Game is that, in Mulligan play, the scorecard is completed in order. For example, since hole 1 on the scorecard 20 is a par 4, the player must accept the score for the par 4 that appears on game piece 10 , and may not select the par 3 or par 5 scores even if these are better.
[0025] For both the Duffers play and Mulligan play versions, it can be seen that there are several results which can require a second roll of the game piece 10 . These are an ace (hole-in-one) on a par 3, an eagle on a par 4, or an eagle on a par 5. If a second roll yields the same score, the player receives that score. If not, the player receives a score that is one stroke worse than the first-rolled score (i.e., a birdie instead of an ace or an eagle).
[0026] In another version of a golf game consistent with an embodiment of the present invention, referred to in the instructions as “Tournament Play,” play proceeds similarly to the Mulligan play version, in the sense that the holes are played in order and no use is made of weather, hazard, or risk reward information. However, players are given the opportunity, through an additional roll of the game piece, to better certain scores. For example, a player playing a par 3 and rolling a par or a bogie with the first roll can better his/her score by one by rolling a second time and coming up with “putter” or any “wild” in the club column. A player playing a par 4 and rolling a par or a bogie with the first roll can better his/her score by one by rolling a second time and coming up with “wedge” or any “wild” in the club column. A player playing a par 5 and rolling a par or a bogie with the first roll can better his/her score by one by rolling a second time and coming up with “driver” or any “wild” in the club column.
[0027] The final version of a golf game consistent with an embodiment of the present invention is referred to in the instructions as “Championship Play.” In this version, additional variables are added to the play, which proceeds in the normal hole order. Preferably, prior to the start of the round, the game piece 10 is rolled to determine weather—i.e., perfect, windy, gusty, wind and rain. Additionally, it may be desired to allow each player to roll the game piece 10 , to determine if that player will be affected by the weather condition. For example, if the first roll is “rain” and the player also rolls “rain,” that player will not be affected by weather in his/her scoring. However, if the two weather conditions do not match, the player will be affected by the first rolled weather condition.
[0028] If the weather is “perfect,” players should be given the opportunity to improve their score for each hole played, when they score a par or a bogie, by making a second role—as described above.
[0029] As an added element of difficulty, “challenges” can be incorporated into the game. For example, as shown in FIG. 4 , the number of challenges can be a function of the weather conditions—with no challenges for perfect weather, 1 for gusty, 2 for windy, 3 for rain, and 4 for wind and rain. The challenge holes can be set in advance of the game, or players can be randomly challenged by their opponents.
[0030] A player rolling in response to a challenge must take into account not only the score for the hole being played (par 3, par 4 or par 5), but also the score shown in the hazard column (the third column from the left). In this embodiment, a stroke is added if the player has rolled OB (out of bounds), UPL (unplayable lie), or water. If the player rolls rough or sandtrap, the player rolls again. If he/she rolls the a putter for a par 3, a wedge for par 4, or a driver for par 5, no extra stroke is added—if not, a single stroke is added to the player's score. | A portable golf game utilizing a rollable game piece. The game piece has a plurality of flat sides, so that upon rolling the game piece it will come to a resting position, displaying to the player(s) information on one of the flat sides. That information includes scoring information for golf holes that are being played in a simulated fashion, and may also include information concerning clubs, hazards, weather, and risks/rewards. Preferably, a scorecard is also provided, so that scores may be recorded. It is further preferred that the game piece be hollow, so that the scorecard may be stored therein. | 0 |
RELATED CASES
This application is a division of application Ser. No. 08/354 359 filed Dec. 13, 1994 now U.S. Pat. No. 5,462,505 which is a continuation-in-part of my patent application Ser. No. 08/134,093, filed Oct. 12, 1993 and now abandoned.
BACKGROUND
1. Field of the Invention
This invention relates to inflatable structures and is particularly directed to portable inflatable structures for indoor and outdoor use as exercise and play areas for children.
2. Prior Art
For several year, it has been known that numerous structures can be created by providing frameworks of hollow tubing and delivering a constant flow of low pressure air into such tubing to erect and maintain the erection of the framework. Moreover, panels of various materials can be secured to such frameworks to create closed buildings. Such inflatable structures have found considerable acceptance as temporary buildings for a wide variety of purposes. It has also been known to provide large inflatable mattresses for use as trampoline-type devices for the children's areas of amusement parks and the like. However, all of the prior art inflatable structures and trampoline-type devices have been designed for outdoor use. Consequently, these prior art inflatable structures have been relatively large and bulky. Because of this, these inflatable structures have not been considered suitable for indoor use. Furthermore, in an indoor environment, the inflatable trampoline-type devices have generally been considered to be unsafe, since a child bouncing on the device could fly off and strike nearby furniture, causing injury to the child and possible damage to the furniture.
BRIEF SUMMARY AND OBJECTS OF INVENTION
These disadvantages of the prior art are overcome with the present invention and improved inflatable structures are provided which are dimensioned for indoor use and which have a trampoline-type floor, yet which are completely safe for use in a confined area.
The advantages of the present invention are preferably attained by providing an inflatable structure having a trampoline-type floor with an inflatable framework projecting upwardly therefrom and having netting panels extending between adjacent portions of said framework to prevent a child from inadvertently bouncing out of the structure, with at least one of said panels having releasable fastening means to allow opening of said one of said panels as a door.
These and other objects and features of the present invention will be apparent from the following detailed description, taken with reference to the figures of the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an isometric view of an inflatable structure embodying the present invention;
FIG. 2 is a transverse section through the base of the inflatable structure of FIG. 1 taken on the line 2--2 of FIG. 1;
FIG. 3 is a plan view of an alternative form of the inflatable structure of FIG. 1;
FIG. 4 is a right end view of the inflatable structure of FIG. 3;
FIG. 5 is a vertical section through an alternative form of the inflatable structure of FIG. 1;
FIG. 6 is a longitudinal section through the inflatable structure of FIG. 5;
FIG. 7 is a plan view of the inflatable structure of FIG. 5, with parts broken away for clarity: and
FIG. 8 is a view, similar to that of FIG. 5, showing an alternative form of the inflatable structure of FIG. 5;
FIG. 9 is a longitudinal section through the inflatable structure of FIG. 8; and
FIG. 10 is a plan view of the inflatable structure of FIG. 8 with parts shown in phantom for clarity.
DETAILED DESCRIPTION OF THE INVENTION
In that form of the present invention chosen for purposes of illustration in the drawing, FIG. 1 shows an inflatable structure, indicated generally at 10, having a peripheral, generally rectangular upper tubular member 12, defining a central open area 15, supported by a plurality of spaced vertical tubular members 14, which each communicate with the upper member 12 and with a base 16 formed of a plurality of contiguous tubular chambers 18, 20, 22, 24, 26 and 28 and end members 30 and 32. A fan 34 supplies air under constant pressure to inflate the structure 10 through inlet tube 36, which communicates with end member 30 of the structure 10. Net panels 38, formed of suitable material, such as nylon, are secured to the vertical tubular members 14, the upper rectangular member 12 and to the base 16. When a child walks about on the contiguous chambers 18, 20, 22, 24, 26 and 28, the changing air pressure tends to distort the shape of the inflatable structure 10, which could result in toppling of the inflatable structure 10 and possible injury to the child. However, the net panels 38 also serve to distribute the distorting forces to adjacent portions of the inflatable structure 10and, hence, serve to prevent toppling. One of the net panels 38 is secured along only one edge to an adjacent vertical member 14 and carries releasable closure means 42 on its free edge 40 which is mateable with corresponding closure means 44 on an adjacent one of the vertical members 14. The closure means 42 and 44 may be slide fasteners, strips of hook-and-loop material or other suitable means for releasably securing the free edge 40 to the adjacent vertical member 14 to serve as a door for allowing persons to enter and leave the structure 10. As seen in FIG. 2, the interiors of the tubular members 18, 20, 22, 24, 26 and 28 of the base 16 have free communication with the interiors of the vertical members 14, which have free communication with the interior of the rectangular upper member 12, as sen at 48 in FIG. 2. However, between the tubular members 18, 20, 22, 24, 26 and 28 of the base 16, suitable flow restricting valve means 48 are provided to permit air flow between the adjacent tubular members of the base 16, but to limit the rate of such flow.
In use, the inflatable structure 10 can be compactly folded for storage and, in this condition, can readily be transported to any desired location. On arrival at a desired location, the user turns on the fan 34, which sends air under constant pressure through inlet tube 36 into end tube 30 of the base 16. From end tube 30, the air flows freely through the tubular members 18, 20, 22, 24, 26, 28 and 23 of the base 16 and through vertical members 14 and the rectangular upper member 12, which serves to 9 inflate and erect the structure 10 to the position shown in FIG. 1. When a child steps through door 40 and puts their weight on the tubular members 18, 20, 22, 24, 26, 28, 30 and 32 of the base 16, the flow restricting valves 48 allow restricted air flow between the adjacent members 18, 20, 22, 24, 26 and 28. thus, the tubular members 18, 20, 22, 24, 26 and 28, which provides a cushioning action. This allows one or more children within the structure 10 to walk about or bounce on the base 16, in a trampoline-like manner, while the vertical members 14 and net panels 38 retain the children within the structure 10and prevent them from bouncing out of the structure 10 to possibly strike and injure themselves on adjacent furniture or other articles. Also, as noted above, the net panels 38 serve to distribute the forces, caused by children walking on the tubular members 18, 20, 22, 24, 26 and 28, and, hence, serve to prevent toppling of the inflatable structure 10 and possible injury to the children. Later, when desired, the structure 10 can be deflated and folded for convenient storage.
Alternatively, the structure 10 can be made in smaller dimensions and the door 40 can be fixedly closed. In this instance, the structure 10 can serve as a portable playpen and parents can place toddlers and babies in the structure 10 by inserting the children through the central open area 15 and placing the children on the base 16 within the structure 10. Thus, the structure 10 ensures that the children cannot wander about and encounter dangerous situations. When the parent wishes to leave the location, they lift the child out of the structure 10 through the central open area 15, deflate the structure 10, fold it compactly and transport it to a new location.
FIGS. 3 and 4 show an alternative for, indicated generally at 84, of the inflatable structure 10 of FIG. 1. The inflatable structure 84 is similar to that of FIG. 1 and similar reference numbers are used for similar parts. However, in this form of the present invention, the base 16 has tubular chambers 18, 28, 30 and 32 extending about the periphery of the base 16, while the central portion of the base 16 is formed by a plurality of hollow, generally triangular chambers 88, 90, 92, 94, 96, 98 and 100, which communicate with the tubular chambers 18, 28, 30 and 32, and with a central circular chamber 101, through acoustic air valves 102. The acoustic valves 102 allow air to pass into and out of the adjacent ones of the triangular chambers 88, 90, 92, 94, 96, 98 and 100 from the peripheral chambers 18, 28, 30 and 32 and from the central circular chamber 101. In this way, when a child steps on any one of the triangular chambers 88, 90, 92, 94, 96, 98 and 100 or on the circular central chamber 101, the increased air pressure in the chamber stepped on can redistribute throughout the circular central chamber 101, the adjacent triangular chambers 88, 90, 92, 94, 96, 98 and 100 and the peripheral chambers 18, 28, 30 and 32 in such a manner as to prevent all of the air in the stepped on chamber from escaping and, hence, to prevent the child from sinking completely to the ground. Also each of the acoustic valves 102 emits a sound as air passes through the valve 102. As indicated in FIG. 3, by tuning and appropriate selection, the acoustic valves 102 may be made to each emit a sound corresponding to a respective musical note when air passes into or out of the assosciated one of the triangular chambers 88, 90, 92, 94, 96, 98 or 100. Obviously, if desired, the acoustic valves 102 could be air valves which serve as switches to actuate a remote sound source, a signalling lamp or other appropriate device.
In use, children may play with the inflatable structure 84 in the same manner as described above with respect to the inflatable structure 10 of FIG. 1. In addition, when the children jump on any of the triangular chambers 88, 90, 92, 94, 96, 98 and 100, a musical tone will be emitted by air passing into or out of the respective chambers 88, 90, 92, 94, 96, 98 and 100 through the respective acoustic valves 102. Also, the children can cause the acoustic valves 102 to play a song by jumping on appropriate ones of the triangular chambers 88, 90, 92, 94, 96, 98 and 100. At the same time, the valves 102 serve to allow redistribution of the air pressure among the triangular chambers 88, 90, 92, 94, 96, 98 and 100 and the central circular chamber 101 to prevent a child standing on any of the chambers from sinking completely to the ground.
FIG. 5 is a vertical section through an alternative form, indicated generally at 50, of the inflatable structure of FIG. 1. In this form of the present invention, a pair of circular tubes 52 and 54 are mounted in parallel spaced relation and are joined by a plurality of circular tubes 56, 58, 60 and 62, each having their axis extending perpendicular to the axes of tubes 52 and 54 and each being rotated approximately 30° with respect to the adjacent tubes. As best seen in FIGS. 5 and 7, a net 64, formed of suitable material, such as nylon webbing, extends between the tubes 52 and 54 to form a supporting surface for a person 66. Attaching straps 68 extend about the juncture of the tubes 56, 58, 60 and 62 and each carries a connecting ring 70. The person 66 wears a suitable safety harness 72, having a waist belt 74 and shoulder straps 76, and attaching straps 78 are secured to the waist belt 74 by suitable swivels 80 and have swivel mounted snap hooks 82 releasably connecting the opposite ends of the attaching straps 78 to the connecting rings 70. The tubes 52, 54, 56, 58, 60 and 62 are inflated by suitable means, not shown, to a pressure sufficient to substantially retain their shape even when the person 66 is standing on the supporting surface 64.
In use, the structure 50, when uninflated, can be folded to be quite compact and can easily be carried in a backpack or the like for transportation to a desired location. At the desired location, the tubes 52, 54, 56, 58, 60 and 62 are inflated by suitable means, such as a manual pump. Thereafter, the person 66 steps onto the supporting surface 64, puts on the safety harness 72 and secures the attaching straps 78 to the waist belt 74 and to the connecting rings 70. Thereafter, the person 66 can walk on the supporting surface 64 and the change in location of the weight of the person 66 will cause the structure to roll on the tubes 52 and 54 and, hence, to transport the person 66 within the structure 50. Because the tubes 52, 54, 56, 58, 60 and 62 are inflated, the structure 50 will be quite bouyant and, in fact, will support the person 66 even on water. Thus, by walking on the supporting surface 64, the person 66 can use the structure 50 as a means of transportation across land and water. Upon arrival at a desired destination, for example, after crossing a river, the person 66 can quickly and easily deflate the structure 50 and can restow the structure 50 in a backpack or the like for transportation over land. It will be seen that the structure 50 can serve as an exercise or amusement device on both land and water. Moreover, the structure 50 can serve as an emergency means of transportation for facilitating military personnel to cross rivers and the like, without bridges, boats or other convention means of water transportation.
FIGS. 8, 9 and 10 show an alternative form of the inflatable structure 50 of FIGS. 5, 6 and 7. Indicated generally at 90, this form of the present invention is generally similar to that of FIGS. 5-7, having a pair of circular tubes 52 and 54 mounted in parallel spaced relation and joined by a plurality of circular tubes 56, 58, 60 and 62, each having their axis extending perpendicular to the axes of tubes 52 and 54 and each being rotated approximately 30° with respect to the adjacent tubes. However, the web 64, the attaching straps 68 and safety harness 72-78 of the structure 50 of FIGS. 5-7 are replaced by rigid spider members 92 having shafts 94 and 96 projecting perpendicularly inward from the axis of the spider members 92. A chair 98 has sleeves 100 and 102 encircling the shafts 94 and 96 to suspend the chair 98 and suitable bearings, not shown are provided to permit the sleeves to rotate freely on the shafts 94 and 96. As best seen in FIGS. 9 and 10, a motor 104 is mounted on the chair 98 below the seat 106 and serves to drive a chain or belt 108 which rotates a pulley 110 which is mounted on the inner end of shaft 94 and serves to rotate shaft 94 to propel the inflatable structure 90. A flywheel 112 is mounted between the opposite end of motor 104 and and the chair 98 and serves to stabilize the chair 98. Finally, a control panel 114 is mounted on the chair 98, within easy reach of a person seated on the seat 106, to permit the person to start, stop and regulate the speed of the motor 104 and, hence, of the inflatable structure 90. | An inflatable structure having a trampoline-type floor with an inflatable framework projecting upwardly therefrom and having netting panels extending between adjacent portions of said framework to prevent a child from inadvertently bouncing out of the structure, with at least one of said panels having releasable fastening means to allow opening of said one of said panels as a door. | 0 |
CROSS-REFERENCED TO RELATED APPLICATIONS
[0001] Not applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable
BACKGROUND OF THE INVENTION
[0003] I. Field of the Invention
[0004] This invention is directed generally to the field of agriculture machinery, and more particularly, it relates to implements associated with soil trench closing mechanisms adjusted with controllers. Associated implements include seed planting devices, fertilizer applicators, tillage closers, irrigation drip line equipment, and related products. Specifically, the invention relates to row treating units incorporating a combination of tools in the form of closing devices and soil packing devices, also known as closing wheels and soil firming/packing wheels. The units are designed to be attached to the rear of seed planting implements or other ground engaging equipment. The deployment of and/or down force exerted by the closing wheels and packing wheels are independently adjustable and use pneumatic operators for controlling up and down adjustments.
[0005] II. Related Art
[0006] In the spring or fall, prior to planting, farmers must prepare their fields for accepting seed. Many tillage implements have been designed and are used to condition the soil in preparation for planting. Traditional farming includes both primary and secondary tillage tasks to prepare the soil such as plowing, disking, field cultivating and harrowing. Disking is an example of a method of primary tillage and harrowing is an example of a method of secondary tillage.
[0007] Primary tillage is an optional first pass over the soil using a soil conditioning implement attached to the rear of a tractor which works deep into the soil. The soil is usually worked several inches deep to break up clods of soil, remove air pockets, and destroy weeds deep in the earth.
[0008] Secondary tillage involves another pass over the same soil, at a more shallow depth, using implements which are generally attached to the rear of the primary tillage unit or to the front of a planter such that the secondary tillage unit follows the primary tillage unit. The secondary tillage unit generally may work the soil to a depth of a few inches or more, but usually not to exceed the desired seed planting depth. More recently, secondary tillage may be the only soil conditioning that takes prior to planting.
[0009] A secondary tillage unit is usually a final conditioning tool to prepare the soil for planting. Thus, rotating blade coulter units may be used to chop up crop residues and loosen the soil; and row cleaners, which include a pair of converging multi-bladed trash wheels, used to move the crop residue out of the way to provide a cleared area for rows to be planted. Rolling baskets also may be used to break up soil clods and break up any crust on the top of the soil prior to planting.
[0010] After the soil has been prepared and crop residue moved out of the way, the planting/seeding operation takes place. Seeding devices are multi-row devices pulled by tractors and include opening disks that create an open seed trench that allows for seed to be dropped into soil at a metered rate and set depth. Thereafter, the trenches made by the opening disks must be closed with the proper amount of pressure and the soil firmed/packed. This is preferably done using, in combination, pairs of closing wheels followed by firming/packing wheels which are mounted on a row unit or tool bar. A combination of these implements is associated with each row unit on the seeding equipment.
[0011] Closing wheels are usually mounted in pairs that are angled to converge rearward of the seeding equipment. The closing wheels are designed to crush and crumble trench walls from both sides. They may take any of several forms including round rubber wheels, or wheels with radially distributed spikes. The sets of closing wheels are mounted on assemblies that include springs that apply downward force to pivot the closing wheel mounts and force the closing wheels to the ground. The downward force may be adjusted by adjusting the tension in the spring. A problem with prior closing wheel assemblies is that in some instances the force will cause the closing wheels to penetrate to a depth that interferes with the seeds planted at the bottom of the trench and cause problems with seed spacing and depth. This may even lead to some seeds being thrown from the seed trench or uneven emergence.
[0012] Mounting systems for firming/packing wheels are typically provided with a down force spring arrangement, but have no ability to lift the packing wheel or reduce pressure desired. The packing wheels are designed to follow the closing wheels to firm/pack the soil over the seeds. This must be accomplished with a proper amount of pressure to be successful. Thus, too little pressure results in voids or air pockets in the soil, and too much pressure will compact the soil too tightly making it difficult for the plants to sprout through the hard packed soil, and roots will be obstructed by the seed trench compaction all season and will not penetrate the ground as easily as desired. Too little compaction will allow soil to dry out too soon.
[0013] It would present a desirable advantage if the depth and amount of pressure exerted by the closing mechanisms could be more closely and conveniently controlled.
SUMMARY OF THE INVENTION
[0014] By means of the present invention there is provided a row implement treating unit that combines a soil trench closing assembly and a firming/packing wheel assembly for attachment to a multi-row implement. Certain embodiments may include the trench closing assembly without the firming/packing wheel. Embodiments of the unit generally include a soil trench closing assembly and is provided with a pair of height adjustable closing wheels and a closing wheel mounting arrangement that operates the closing wheels and a down-force device for applying a down force to the closing wheels to force them to penetrate the soil. Optionally, a single wheel system can be used. This is used in combination with an adjustable depth limiting or positive stop device to control or limit lowest height adjustment and thereby limit the degree of soil penetration to a desired setting or to raise the lower limit of the closing wheels to a height above the ground. Alternatively, the trench closing assembly may be an active actuator system that includes a device to raise the closing wheels.
[0015] In most preferred embodiments, the unit also includes a firming/packing wheel assembly which includes a packing wheel and a packing wheel mounting and actuating arrangement for deploying and lifting the packing wheel which has a pivotally-mounted framework preferably operated by a pneumatic control system which includes down-force and lift pneumatic devices. A down-force only embodiment is also shown.
[0016] In one arrangement, the pneumatic control system for the firming/packing wheel includes a single down-force airbag and a pair of smaller lift airbags. In an alternate embodiment, the system includes aligned, opposed down-force and lift airbags located between fixed plate members with a traveling intermediate plate member therebetween which operates the pivotally-mounted framework arrangement for the packing wheel mounting framework. The pneumatic control operating system for the packing wheel further includes mechanical down-force and lift stop devices to limit down-force and lift travel of the packer wheel.
[0017] The system may also include a debris deflector mounted ahead of the closing wheels and the unit may be provided with a follower angle adjustment arrangement for adjusting the follower angle between the row unit and any main unit to which it is attached.
[0018] Operation and adjustment of the pneumatic devices of the row units may be controlled from the cab of a prime mover, normally, a tractor, which is attached to pull an associated seeding device or other tow bar arrangement to which one or more of the row units is attached. In addition, sensors may be provided that provide information that can be used to automatically control aspects of the operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In the drawings wherein like reference characters denote like parts:
[0020] FIG. 1 is a perspective view of one row treating unit embodiment that includes a combination of spiked closing wheels and a packing wheel in accordance with the invention;
[0021] FIG. 2 is a perspective view of the embodiment of FIG. 1 with smooth closing wheels;
[0022] FIGS. 3A and 3B are fragmentary perspective views of the embodiment of FIG. 1 further illustrating the operating systems;
[0023] FIGS. 3C and 3D are fragmentary views with parts removed for clarity that illustrate mechanical lift and down stops for the pivoting arm mount arrangement for raising and lowering the packing wheel of the embodiment of FIG. 1 ;
[0024] FIG. 4 is a side partial sectional view of through the embodiment of FIG. 1 showing the mechanism with the packing wheel fully deployed and the closing wheels raised;
[0025] FIG. 5 is a view similar to FIG. 4 with the packing wheel also raised;
[0026] FIG. 6 is a sectional view similar to FIG. 4 with both the closing wheels and the packing wheel deployed in a down position;
[0027] FIGS. 7A and 7B are top and side elevation views of an alternate embodiment of a row unit in accordance with the invention;
[0028] FIG. 8 is a perspective view showing the mechanism of the embodiment of FIGS. 7A and 7B with parts removed for clarity;
[0029] FIG. 9 is a view of the embodiment of FIGS. 7A and 7B shown with both the closing wheels and the packing wheel in a raised position;
[0030] FIG. 10A is a view of the alternate embodiment including smooth closing wheels and a cylinder closing wheel deployment mechanism shown in the deployed or down position;
[0031] FIG. 10B is a view similar to that of FIG. 10A with the deployment mechanism in the retracted or lifted position;
[0032] FIG. 10C is a view similar to FIGS. 10A and 10B except that an airbag is used to produce the down force on the closing wheel assembly;
[0033] FIGS. 11A and 11B illustrate the use of left and right adjustment bolts to adjust the angle of the row unit, including the packer wheel, left and right of dead center;
[0034] FIG. 12A is a fragmentary side view with parts removed for clarity of a closing wheel arrangement using a pneumatic down-force actuator and movable wedge travel limiting assembly;
[0035] FIG. 12B is a view similar to that of FIG. 12A provided with a dual aligned down-force and lift actuator arrangement
[0036] FIGS. 13A and 13B depict side views of an embodiment of a row treating unit employing a packing wheel only with a down-force actuator and adjustable mechanical stop shown in lowered and raised positions, respectively;
[0037] FIGS. 13C and 13D depict side views of an embodiment of a row treating unit in which the packing wheel of FIGS. 13A and 13B is combined with a closing wheel arrangement;
[0038] FIGS. 14A and 14B depict a typical 2-position plunger-operated five-port valve associated with the operation of pneumatic operators in accordance with the invention shown in alternate position;
[0039] FIGS. 15A , 15 B and 15 C show additional implements used prior to planting that may be pneumatically operated;
[0040] FIG. 16 is a schematic representation of a multi-row pneumatic system for operating a plurality of spaced row treating units that may be attached to a tow bar or multi-row seed planting implement;
[0041] FIG. 17 depicts a pneumatic system that can be used to operate the pneumatic actuators associated with a system employing a number of row units; and
[0042] FIG. 18 is a view of a possible cab control panel associated with controlling the operation of one or more row units.
DETAILED DESCRIPTION
[0043] The detailed description of the illustrative embodiments is intended to illustrate representative examples of the inventive concepts and is not intended to limit the scope of those concepts. The examples are to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top” and “bottom”, “left” and “right” as well as derivatives thereof (e.g., “horizontally”, “downwardly”, “upwardly”, etc.) should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as “connected”, “connecting”, “attached”, “attaching”, “join” and “joining” are used interchangeably and refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece, unless expressively described otherwise. As used herein, the term “trench closing mechanism” is meant to include any configuration of wheeled seed, fertilizer, tillage, etc., trench closing device and may be used interchangeably with trench closing wheels. The terms “firming wheel”, “firming/packing wheel” and “packing wheel” are also used interchangeably for such wheel devices used in conjunction with closing systems.
[0044] The term “airbag” as used herein is defined to mean any type of inflatable pneumatic operator, without limitation, including convoluted and non-convoluted devices with single and multiple air access ports, and ports at different locations.
[0045] FIG. 1 illustrates a row treating unit generally at 20 that includes a trench closing mechanism assembly 22 and a firming/packing wheel assembly 24 . An optional debris deflecting attachment 25 is mounted ahead of the trench closing wheels to deflect rocks and other field debris that otherwise might damage the closing wheels or cause them to skid because rock or debris becomes lodged between the closing wheels.
[0046] The trench closing wheel assembly includes a pair of converging spiked closing wheels 26 mounted on stub axles as at 28 which is carried by a heavy structural frame 30 which includes spaced heavy flanking shaped side plate members 32 and 34 , each of which is designed to pivot about a fulcrum pivot joint as at 36 as the closing wheel mounting assembly moves up and down.
[0047] As best seen in FIGS. 4 and 5 , side plate members 32 and 34 are connected to a shaft 40 that extends between the side plate members and carries one end of a tension spring 42 which is also connected to lever member 44 that is fixed to an independent fixed support structure arrangement 46 so that the tension spring 42 tends to pivot the trench closing assembly downward forcing the spikes 48 of the closing wheels 26 into the ground. The maximum depth of soil penetration of the closing wheels is limited by a stop system that includes an adjustable set screw 50 that is threaded through a top plate 52 of the trench closing wheel assembly and contacts a fixed gusset member 54 to thereby adjustably limit the downward travel of the wheel mounting assembly. As pictured in FIGS. 4 and 5 , the set screw 50 is almost fully extended toward the gusset member 54 and the closing wheels 26 are therefore in a raised position. In FIG. 6 , the set screw is backed off, thereby permitting the spiked wheels 26 to enter the soil, a controlled or limited amount.
[0048] It is important for the closing wheels to be mounted on a resilient system that enables them to raise up to prevent damage if obstacles are encountered. The spring biased mounting enables the closing wheels to rise out of the way when they encounter something hard in the soil such as a rock. The optional adjustable stop system enables the maximum depth of the closing wheels to be adjusted as necessary to accommodate seed trenches of varying depths. The maximum depth penetrated by the closing wheels needs to be shallower that the depth of the planted seeds to avoid interference with the seeds. The closing wheels are designed to crush and crumble the seed trench walls without disturbing the planted seeds. Several different kinds of wheels are used and FIG. 2 shows the use of smooth edge wheels rather than spiked wheels. An important aspect of the present system is the adjustability of the maximum depth of the closing wheels. The set screw position can be adjusted as often as desired. Also, other devices can be used to apply the down force to and limit penetration of the closing wheels.
[0049] The packing wheel assembly 20 has a pivoting framework that includes a pair of rather long spaced, generally arcuate, shaped support arm members 70 and 72 connected together by spaced cross members 74 and connected at their free ends to a yoke 76 which carries the packing wheel 78 on a shaft or axle 80 . The support arm members with bushings 82 are pivotally mounted on a bolt shaft 84 in structural shape 86 that extends through fixed support structure 46 . The packing wheel assembly is operated by a pneumatic system that includes airbags. This embodiment includes three airbags, a single down-force airbag 90 and a pair of smaller spaced lift airbags 92 and 94 . As best seen in FIGS. 3C and 3D , the down-force airbag 90 operates between a fixed plate 96 attached to the support structure and a bent flange member 98 that is pivotally fixed to the spaced support arms 70 and 72 at pivot points 100 and 102 , respectively. Reinforcing gusset members are shown at 104 and 106 . The lift airbags 92 and 94 operate between fixed plates 108 reinforced by gusset member 110 and a lift pedestal member 112 which, in turn, is carried on a lift pin 114 , which is journaled in support arm members 70 and 72 .
[0050] In operation, as best seen in FIGS. 3A-3D , when the packing wheel is raised, the down-force airbag is vented and the lift pedestal member is displaced forward as the lift airbags extend. A lift stop is reached when the lift pin 114 contacts the fixed plate member 96 ( FIG. 3C ). Conversely, when the packing wheel is deployed in the ground-engaging position, the down-force airbag inflates and the lift airbags are vented and deflate. A downward limit stop is provided when the lift pedestal member is displaced rearward by the lift pin 114 . As the support arm members are lowered, contacts a down stop plate 116 , which also determines the minimum length of the lift airbags ( FIG. 3D ). Of course, pressure can also be supplied to both lift and down-force airbags in any desired combination to provide any desirable controlled down force to the packing wheel to adjust to any soil condition.
[0051] An alternate embodiment of the row unit of the invention is shown in FIGS. 7A through 11B . The row unit, generally 200 , includes a seed trench closing wheel assembly 202 , packer wheel assembly 204 and debris deflector 206 .
[0052] The trench closing wheel assembly is similar to the previously described embodiment and includes a pair of converging spiked closing wheels 208 , smooth rimmed wheels and/or flat or concave disk members 210 ( FIGS. 10A-10C ) mounted on axles or shafts 212 which extend through heavy shaped side plate members 214 and 216 connected by heavy top plate member 218 . As with the previous embodiment, the side plates are attached to pivot about a fulcrum at 220 . As shown in FIG. 8 , a shaft 222 extends between the side plates and carries one end of a heavy tension spring 224 , the other end of which is connected to a fixed lever 226 . As with the previous embodiment, the tension spring 224 provides the down force to pivot the closing wheel assembly downward. Depth adjustment is accomplished using a set screw 228 threaded through to plate 218 and contacting fixed stop member 230 .
[0053] The packing wheel assembly employs a modified operating system, but is otherwise similar to the first described embodiment. It includes a supporting pivoting packing wheel framework including spaced, generally arcuate support arms 250 and 252 spanned by connecting cross members 254 . The arms 250 and 252 are connected at fixed ends to pivot on a pivot arm mounting shaft 256 at 258 and 260 , respectively. The packing wheel framework connects at its free end to a yoke 262 which carries packing wheel 264 on an axle 266 , which may be a bolt member provided with bushings as at 267 and 268 attached to wheels 264 .
[0054] The alternative packing wheel assembly is operated by a fixed dual aligned linear airbag system that includes a down-force airbag 270 and a lift force airbag 272 separated by a central traveling intermediate plate 274 that reciprocates linearly between the airbags. The system airbags are further flanked by a fixed down-force plate 276 and a fixed lift-force plate 278 . The traveling plate 274 is connected or otherwise integral with a double-acting flange 280 which has a pair of arms 282 and 284 that extend along generally parallel to the aligned airbags and connect to the pivot arms using an upper mounting shaft or stub shafts 286 at 288 and 290 .
[0055] As best viewed in FIG. 8 , a heavy set screw 292 is threaded through the lower portion of the fixed lift force plate 278 to contact a lower extension of the traveling intermediate plate 274 , when the down-force bag extends and the lift bag deflates, to limit the rearward travel of the traveling intermediate plate 274 and thereby provide an adjustable stop for downward travel of the packing wheel support arms. Travel in the forward direction is limited by contact between the traveling intermediate plate and a fixed member 294 to thereby provide a positive stop limiting the upward travel of the packing wheel lift arms. As with the previous embodiment, pressure can be supplied to both airbags at the same time to control the net downward force exerted by the packing wheel to accommodate any soil type or condition encountered.
[0056] FIGS. 10A-10C illustrate an embodiment similar to that of FIGS. 7A-9 that utilizes alternate types of actuators in the deployment of the closing wheel arrangement. In FIG. 10A , there is shown a double-acting pneumatic cylinder 300 pivotally attached at 302 between a member 304 fixed to lift-force plate 278 and at 306 pivotally attached to a member 308 fixed to the closing wheel assembly 202 . The actuator is shown with the rod 310 extended which forces the closing wheels into the down or deployed position. A stop arrangement similar to that of other embodiments can be used to limit vertical travel of the closing wheels 210 . Down-force and lift pneumatic connectors are shown at 312 and 314 . It will be appreciated that a hydraulic cylinder arrangement could also be used to deploy the closing wheels.
[0057] FIG. 10B is a view similar to FIG. 10A showing the closing wheels in the raised or fully retracted position. The packer wheel is shown in a deployed or down position in both FIGS. 10A and 10B .
[0058] In FIG. 10C , there is shown a further actuator device for deploying the closing mechanisms in the form of an airbag 320 connected between a fixed member 322 connected between lift-force plate 278 and member 308 . The lower plate 324 is fixed to a member 326 pivotally mounted at 328 to the closing mechanism 202 . Airbag 320 is shown partially extended in FIG. 10C .
[0059] The FIGS. 11A and 11B illustrate a follower angle adjustment system for adjusting the relative angle between the row unit and the main unit to which it is attached. The row unit is shown with the packing wheel assembly removed. The unit is shown hitched pivotally at 400 to a main unit 420 . A heavy mounting flange member 402 is provided as part of the fixed mounting assembly of the row unit. Heavy oppositely disposed adjustment bolts 404 and 406 are threaded through the flange 402 behind the pivot joint at 408 and 410 . The flange member 402 extends over a shaped member 412 to which the row treating unit is hitched. By adjusting the adjustment bolts in and out, the angle between the row unit and the attachment flange can be slightly varied to move the row treating unit to the left or to the right of dead center, if desired, as shown in the figures.
[0060] FIGS. 12A and 12B depict another embodiment of a row unit having a closing wheel arrangement shown generally at 500 that includes a pivotally mounted closing wheel assembly 502 and a mounting assembly 504 . The closing wheel assembly includes a pair of closing wheels, one of which is shown at 506 , carried by a structure pivotally connected at 508 to a fixed mounting structure 510 . The closing wheel assembly includes main structural shapes as at 512 and a travel limiting arrangement that includes a bolt member 514 carried by a flange member 516 . The bolt 514 is threaded through members 518 and 520 . The bolt 514 addresses and adjusts a movable wedge member 522 which, in turn, limits the gap between a top stop plate 524 and a bottom stop plate 526 to determine the vertical travel limit of the wheel 506 .
[0061] The closing wheel assembly 502 is operated by a down-force only pneumatic arrangement in FIG. 12A . That arrangement uses a down-force airbag 540 mounted between a fixed vertical stop member 542 and is fixed to the pivoting wheel assembly by a pivotal mount at 544 . The member 542 is fixed to and carried by a fixed mounting member 546 .
[0062] In FIG. 12B , the closing wheel assembly 502 is operated by an aligned dual airbag system that includes down-force airbag 550 and lift airbag 552 which operate against a fixed intermediate member 554 to raise and lower a shaped flange arrangement that includes a flange member 556 that is vertically adjustable and attached at 558 to the closing wheel assembly and to the airbag system at 560 .
[0063] FIGS. 13A and 13B depict another embodiment of a row unit having a packing wheel arrangement that is not combined with a closing wheel system. The row unit shown generally at 600 and includes a pair of spaced curved support arms, one of which is shown at 602 , which carry a yoke 604 into which is journaled a packing wheel 606 . The arms 602 are mounted to rotate on a pivot joint 608 that is mounted in a fixed attachment structure 610 . The packing wheel is operated by a down-force pneumatic operator which operates between a moveable plate member 614 and a fixed plate member 616 to operate a bent flange member 618 that is connected to the arms 602 at a further pivot joint 620 . The travel distance allowed the system for the deployment of the packing wheel 606 is controlled and limited by an adjustable bolt or rod member 622 .
[0064] In FIG. 13A , the pneumatic operator is inflated and the packing wheel is in the fully down or deployed position with member 614 fully extended along member 622 . Conversely in FIG. 13B , the pneumatic operator 612 is collapsed or deflated and the member 614 is fully retracted along the member 622 to upward stops 624 and the packing wheel is in the fully raised position.
[0065] FIGS. 13C and 13D are views of the embodiment of FIGS. 13A and 13B with the addition of a closing wheel assembly 630 in combination with the packing wheel arrangement. A debris deflector is shown at 632 .
[0066] In FIG. 17 , there is shown a pneumatic system with parts of the enclosure removed to expose certain internal parts. The system, shown generally at 700 , includes an accumulator tank, shown partially at 702 , which may be sized according to the desired capacity of the system for performing the necessary functions. The accumulator tank is provided with mounting legs (not shown) and is designed to be mounted on a multi-row seeding implement, or the like, in a well-known manner. A control box housing the control devices for the system is shown at 704 with parts removed to expose the interior which houses an air compressor 706 , which may be electric or hydraulic. An ignition solenoid is shown at 708 and a pressure switch at 710 , which operates to cycle the compressor in a well-known manner, alternatively, the compressor assembly can be controlled from an ISOBUS capable terminal.
[0067] The compressor output line is shown at 712 and a check valve is shown at 714 that prevents back flow from the tank 702 . A safety pressure relief or pop-off valve is shown at 716 that prevents over pressurization of the system. Control knobs for manually adjusted pressure regulators are shown at 718 and associated output pressure gauges are shown at 720 . These are used to regulate output or operating pressure to the elements of the system and their settings may be changed, if necessary, during operation of the implements, but are preferably preset.
[0068] Blocks of electronic pressure regulators as at 722 can be used to regulate up and down pressure applied to pneumatic operators for various devices controlled by the system which may include trash whips (row clearing devices), coulters, rolling baskets, or the like, employed prior to seeding in addition to post-seeding implements. The electronic pressure regulators may be controlled by commands from a control panel, such as shown in FIG. 18 . A typical 5-way valve is shown at 724 and more fully described in conjunction with FIGS. 14A and 14B .
[0069] FIG. 18 depicts one possible control or switch panel 740 designed to interface between an operator in the cab of a tractor or other prime mover and the pneumatic system. The control is used to send commands to all of the valves and regulators. Thus, buttons P 1 -P 5 represent an array of preset pressures for various regulators. These can be used to fix preferred conditions. The panel also includes a display screen 742 , up and down screen scroll buttons 744 and 746 . A menu button 748 allows the operator to view all menu screens, fault codes, adjustment of dump valve times, maintenance information, etc. An enter button 750 is associated with the menu screens and may also be used to turn on the pneumatic system.
[0070] Controls 752 , 754 and 756 are encoders that enable the operator to change the commanded pressure of each of several regulators.
[0071] The four buttons on the bottom of the switch panel with the word “UP” above them and numerals one through four below them are the buttons that can be used to actuate dump valves and five port valves 724 ( FIG. 17 ). These buttons are used to switch the different attachments from the down position (with the button turned off) to the “UP” position (with the button turned on).
[0072] It will be appreciated that sensors mounted on the row units can transmit data to the cab control system that can also be used to adjust various pressures and/or depth of soil penetration for corresponding implements. Such devices are known.
[0073] FIGS. 14A and 14B are schematic representations of a two-position, five-port air valve assembly (as at 724 in FIG. 17 ) in two alternative positions. The assembly, generally at 770 , includes ports 772 , 774 , 776 , 778 and 780 and cylinder 782 , housing axially adjustable cylinder valve or plunger 784 . The valve body or block is depicted at 786 . Ports 772 and 776 are connected to receive air from a high pressure air source. Thus, port 772 is connected to receive compressed air via a manual regulator to provide lift force. Port 776 is connected to receive air via a controlled source to control down force. Ports 778 and 780 connect respectively to a lift force airbag or other pneumatic operator and a down force operator. Finally, port 774 is a vent port for venting air from either the up force operator or the down force operator.
[0074] In FIG. 14A , the port receiving high pressure air 772 is connected through the valve block with a lift force operator through outlet port 778 with the central valve plunger 784 shifted down (in the drawing) in cylinder 782 in a first position. With the central cylinder in this position, the corresponding down force operator is connected to the vent port 774 via port 780 so that down force operator is enabled to collapse while the lift force operator inflates. This raises the corresponding implement.
[0075] FIG. 14B shows the valve 770 in an alternate position with the central cylinder moved upward (in the drawing). With the plunger in this position, port 776 is connected through the central cylinder to port 780 and port 778 is connected to the central cylinder to vent port 774 and port 772 is deadheaded. With the valve in this position, the source of high pressure air is connected through ports 776 and 780 to the down force operator and the lift force operator is connected to vent through ports 778 and 774 . This will enable the down force operator to inflate and the lift force operator to collapse in accordance with moving the corresponding implement to a lowered or deployed position.
[0076] FIGS. 15A-15C depict additional pneumatically operated implements that can be used with the pneumatic system of the invention. They include a row clearing or trash whip device 800 , in FIG. 15A , with a pair of pneumatic operators, one of which is shown at 802 . A rolling basket device, generally 820 in FIG. 15B with pneumatic operators as at 822 and a combination trash whip and coulter device depicted generally at 840 in FIG. 15C with trash whip blades 842 and coulter wheel 844 . Pneumatic operators are depicted at 846 and 848 .
[0077] FIG. 16 is a schematic representation of a multi-row pneumatic system layout that can be controlled by the system of FIGS. 17 and 18 . The schematic includes a plurality of central section row units 860 and these are flanked by a plurality of wing section units at 862 and 864 . A down-force pressure air line is shown at 866 that supplies down pressure to the center units through a manifold 868 and supplies pressurized down-force air to wing section units 862 and 864 through manifolds 870 and 872 , respectively. A common lift pressure system is shown using air line 876 which supplies manifolds 878 , 880 and 882 . A controlled source is depicted at 884 .
[0078] This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself. | This disclosure is directed to the field of agricultural machinery and relates to implements generally used in combination with a multi-row soil trench closing mechanism. Specifically, the disclosure relates to row treating units adapted to be attached to and following a multi-row planter and incorporating a combination of tools that includes a seed trench closing wheel assembly and a firming/packing wheel assembly. The deployment of and down force exerted by the packing wheel is independently adjustable and controlled using pneumatic air bag operators and the soil penetration of the trench closing wheels is limited. | 0 |
This application is a continuation-in-part of U.S. Ser. No. 09/200,698, filed Nov. 27, 1998, now U.S. Pat. No. 6,066,083 which is hereby incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to implantable radiation therapy devices. More particularly, the invention relates to improved radiation therapy and brachytherapy devices, also known as radioactive therapeutic seeds, for the treatment of oncological and other medical conditions.
2. State of the Art
Radioactive seed therapy is a well known and well accepted medical procedure for the treatment of various oncological and other medical conditions. Seed therapy, also known as interstitial brachytherapy typically involves the implantation of one to one hundred relatively small capsules (seeds) into or around a treatment site. The capsules contain a radioactive isotope which irradiates the treatment site at close range without adversely affecting other parts of the body. Brachytherapy has been used successfully in the treatment of various types of cancers such as prostate cancer. It has also been used to prevent the growth or regrowth of tissues in the treatment of various occlusive diseases such as arteriosclerosis and arthrosclerosis subsequent to balloon angioplasty.
Radioactive therapeutic seeds are carefully designed to possess several important qualities. First, in the case of prostatic interstitial brachytherapy they should be relatively small, approximately 0.025 inch in diameter and approximately 0.16 inch long so that they may be implanted into the prostate gland using minimally invasive instruments and techniques. However, it should be appreciated by those skilled in the art that implantable radioactive sources come in all shapes and sizes. Second, the radioactive isotope must be enclosed in a biocompatible protective package since the seeds are typically not removed and will remain in the body for many years. Third, each seed preferably includes a radiopaque (e.g. high Z material) marker so that it can be located at the treatment site with the aid of fluoroscopy.
The state of the art of radioactive therapeutic seeds is substantially disclosed in seven U.S. Patents: U.S. Pat. No. 5,713,828 to Coniglione for “Hollow-Tube Brachytherapy Device”, U.S. Pat. No. 5,405,309 to Carden, Jr. for “X-Ray Emitting Interstitial Implants”, U.S. Pat. No. 4,891,165 to Suthanthiran for “Device and Method for Encapsulating Radioactive Materials” and U.S. Pat. No. 4,784,116 to Russell, Jr. et al. for “Capsule for Interstitial Implants”, U.S. Pat. No. 4,702,228 to Russell, Jr. et al. for “X-Ray Emitting Interstitial Implants”, U.S. Pat. No. 4,323,055 to Kubiatowicz for “Radioactive Iodine Seed”, and U.S. Pat. No. 3,351,049 to Lawrence for “Therapeutic Metal Seed Containing within a Radioactive Isotope Disposed on a Carrier and Method of Manufacture”, which are each incorporated by reference herein in their entireties. In addition, the art has been significantly advanced in co-owned U.S. Ser. Nos. 09/133,072, 09/133,081, and 09/133,082, which are hereby incorporated by reference herein in their entireties.
The Lawrence patent, which issued in 1967, describes many of the essential features of radioactive therapeutic seeds. Lawrence describes radioactive isotopes (I-125, Pd-103, Cs-131, Xe-133, and Yt-169) which emit low energy X-rays and which have relatively short half-lives. When implanted at a treatment site, these isotopes provides sufficient radiotherapy without posing a radiation danger to the medical practitioner(s), people in the vicinity of the patient, or other parts of the patient's body. Lawrence further describes a protective capsule which contains the isotope and prevents it from migrating throughout the body where it might interfere with healthy tissue. The capsule is cylindrical and made of low atomic number biocompatible materials such as stainless steel or titanium which do not absorb X-rays. The isotope is coated on a rod shaped carrier made of similar X-ray transparent (e.g. low Z) material and is placed inside the capsule cylinder which is then closed. The other patents each provide some improvement over the original Lawrence design.
Despite the fact that radioactive therapeutic seeds have been in use for over thirty years and despite the several significant improvements made in the seeds, many concerns still exist regarding the use of the seeds. One problem is that prior to and during implantation of the therapeutic seeds, the physician must handle the radioactive seeds, and therefore take precautions to limit his or her exposure. The precautions may include the use of lead lined clothing and limiting the time for completing any one procedure. However, such clothing is generally heavy and tiring to wear, and limiting procedure time may not be in the best interest of the patient.
In addition, it is difficult to store radioactive therapeutic seeds, as special radiation shielding materials must be used in the container storing the seeds.
Moreover, there may be situations in which it is desirable to increase the level of radiation emitted by a seed after implantation, or keep the level of radiation at a certain level despite the natural decay of the radioactive source over a more prolonged period of time. For example, it may be desirable to provide a first dosage of radiation for a period of time and then, based upon a later diagnosis, increase the dosage for a second period of time. With the present radioactive implants of the art this can only be done through a subsequent invasive procedure of implanting additional seeds, as radioactive elements decrease their radiation output according to their respective half-life.
None of the art addresses any manner of providing an “inactive” seed which can later, e.g., after implantation, be activated to emit radiation. Likewise, none of the art addresses otherwise increasing the amount of radiation emitted by the seed after the seed is implanted in the patient, or maintaining a level of radiation over a longer period of time than the half-life of the radioactive isotope in the implant would otherwise permit.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide radioactive therapeutic seeds which have means for controllably altering the radiation transmitted through the seed capsule.
It is also an object of the invention to provide radioactive therapeutic seeds which are controllably activated to “turn on” the seeds to cause radiation to be emitted therefrom or to increase the radiation emitted therefrom.
In accord with these objects which will be discussed in detail below, the radioactive brachytherapy seeds of the present invention generally include an outer capsule containing a radioactive material, and a substantially radiopaque shield which in a first (pre-implantation) configuration substantially obstructs radiation emitted by the radioactive material. One or both of the radioactive material and the shield are controllably movable relative to the other into a second (post-implantation) configuration such that the radioactive material is at least partially unobstructed by the shield. As a result, the level of radiation emitted by the seed is increased. For purposes herein, “radiopaque” refers to the property of having a relatively “high Z” value, and the terms “radiopaque” and “high Z” are used interchangeably herein.
Various embodiments of the radioactive material and the radiopaque shield are provided. In a first embodiment, a low melt temperature low Z material, e.g., wax, includes radioactive particles suspended therein. The low Z material is preferably substantially provided entirely within a high Z casing. The low Z material, with radioactive particles therein, may be heated and forced to flow, by pressurized fluid or mechanical means, through an opening in the high Z casing to at least partially surround the high Z casing and substantially cause the seed to emit radiation. In a second embodiment, an elastic or heat shrinkable casing is stretched over a radioactive material and a high Z material is deposited on the casing. When the radioactive material is heated to a melted state, the force of the casing on the radioactive material moves the radioactive material out of the casing, the casing collapses, and the radioactive material surrounds the high Z material on the casing to initiate or increase radiation emission from the seed. In a third embodiment, a flowable radioactive material is retained within a radiopaque casing by a removable barrier. The barrier may be removed by melting (e.g., a wax stopper barrier), breaking, or by a valve mechanism, and a pressurizing agent then forces the flowable radioactive material to surround the radiopaque casing. In a fourth embodiment, a first member is provided with regions upon which a radioactive isotope is deposited. The first member is disposed within a second member which includes one or more substantially radiopaque regions through which transmission of radiation is limited and one more substantially radiotransparent regions through which the radiation may be transmitted. In a first configuration, the radiopaque regions are positioned over the radioactive isotope regions. The first member may be controlled to move relative to the second member, e.g., by heat, vibration, or inertia, into a second configuration wherein the radiotransparent regions are positioned over the isotope and substantially permit the emission of radiation by the seed. In a fifth embodiment, a radiopaque shape memory alloy coil element is provided over an elongate element having an isotope deposited on a portion thereof. The rings of the coil are in a naturally compressed state over the portion of the elongate element on which an isotope is provided to prevent transmission of radiation through the rings of the coil and out of the outer capsule. The coil is trained to expand when heated and expose the portion of the elongate element provided with the isotope. In a sixth embodiment, a plurality of radiopaque shape memory alloy elements are provided, with each element having a portion on which an isotope is deposited. The portions provided with the isotope are initially oriented inward such that they do not emit radiation through the outer capsule. The elements are trained such that when they are heated, the elements change shape (or otherwise move) to substantially expose the portions provided with the isotope and thereby substantially initiate emission of radiation.
It will be appreciated that in embodiments utilizing heat to “activate” the seed, the heat may be provided by hot water, microwave technology, or other radiating means provided at or near (e.g., from adjacent to a few feet away) the seed implant site. Additional means for substantially “activating” or at least increasing seed radioactivity may also be used.
It will be further appreciated that the ability to control the amount of radiation emitted by the seed enables the physician to “turn on” the seed or at least increase the radiation emitted by the seed when desired; i.e., upon the application of non-ambient energy, preferably of a predetermined amount. In addition, the seeds may be relatively safely handled without cumbersome precautions prior to activation.
Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a section view of a first embodiment of an at least partially activatable brachytherapy seed in an “inactive” configuration;
FIG. 1A is a section view of an alternate first embodiment of an at least partially activatable brachytherapy seed in an “inactive” configuration;
FIG. 2 is a section view of the first embodiment of an at least partially activatable brachytherapy seed in an “activated” configuration;
FIGS. 3 and 4 are section views of a second embodiment of an at least partially activatable brachytherapy seed in “inactive” and “active” seed configurations, respectively;
FIGS. 5 and 6 are section views of a third embodiment of an at least partially activatable brachytherapy seed in “inactive” and “active” seed configurations, respectively;
FIGS. 7 and 8 are section views of a fourth embodiment of an at least partially activatable brachytherapy seed in “inactive” and “active” seed configurations, respectively;
FIGS. 9 and 10 are section views of a fifth embodiment of an at least partially activatable brachytherapy seed in “inactive” and “active” seed configurations, respectively;
FIGS. 11 and 12 are section views of a sixth embodiment of an at least partially activatable brachytherapy seed in “inactive” and “active” seed configurations, respectively;
FIGS. 13 through 15 are cross section views of the seventh embodiment of “inactive”, “transitional” and “activated” seed configurations, respectively; and
FIGS. 16 through 19 are cross section views of an eighth embodiment of an at least partially activatable brachytherapy seed in “substantially inactive”, “first transitional”, “second transitional”, and “activated” seed configurations, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, a radiation therapy seed 10 according to the invention is shown. The seed 10 includes an inner capsule 12 , preferably made from a radiopaque material, such as lead, provided within a biocompatible outer capsule 14 , preferably made from titanium, aluminum, stainless steel, or another substantially radiotranslucent material. Alternatively, referring to FIG. 1A, the inner capsule may be made from a radiotranslucent material and its exterior surface 25 a may be coated or other provided with, e.g., as a sleeve, a radiopaque material 24 a. Furthermore, while not preferred, the radiopaque material may be provided to the interior surface 27 a of the inner capsule 12 a (either by deposition thereon or an internal sleeve provided thereagainst). The outer capsule 14 is sealed closed about the inner capsule 12 according to any method known in the art, including the methods disclosed in previously incorporated U.S. Ser. No. 09/133,081. For treatment of the prostate, the outer capsule preferably has a diameter of less than 0.10 inches, and more typically a diameter of less than 0.050 inches, and preferably has a length of less than 0.50 inches, and more typically a length of less than 0.16 inches.
The inner capsule 12 includes first and second ends 16 , 18 , and respective first and second openings 20 , 22 at the respective ends. The inner capsule 12 is preferably coaxially held within the outer capsule 14 at the first and second ends 16 , 18 of the inner capsule 12 , such that a preferably uniform space 28 is provided between the inner and outer capsules.
At the first end 16 , the inner capsule 12 is at least partially filled with a meltable solid radioactive material 30 . The radioactive material is preferably a low temperature melting, low Z carrier in which particles 31 provided with a radioactive isotope 33 are suspended. For the carrier, a low melting point is preferably characterized by under 160° F., and more preferably under 140° F. but over 105° F., such that at room temperature and body temperature, the seed is inactive as the radioactive material is substantially contained within the radiopaque inner capsule 12 . Wax is a preferred carrier, although other carriers such as certain metals and polymers may be used. Exemplar isotopes include I-125, Pd-103, Cs-131, Xe-133, and Yt-169, which emit low energy X-rays and which a have relatively short half-life.
A piston 32 is provided in the inner capsule 12 and, upon the liquefaction of the radiopaque material 30 , is capable of moving, e.g., by sliding, along a length of the inner capsule. A spring element 34 is provided between the second end 18 of the inner capsule 12 and the piston 32 , forcing the piston against the radiopaque material.
Turning now to FIG. 2, when it is desired to increase or initiate radiation emission by the seed, that is, “activate” the seed, the seed may be “activated” by applying heat which causes the radioactive material 30 to melt. The heat may be applied, for example, by hot water provided in the urethra (for seeds implanted to treat prostatic conditions), by microwave radiation, or by other types of radiation. The spring element 34 provides force against the piston 32 which, in turn, forces the radioactive material 30 out of the first openings 20 and into the space 28 between the inner and outer capsules 12 , 14 . The second openings 22 permit gas trapped between the inner and outer capsules 12 , 14 to be moved into the inner capsule 12 as the radioactive material 30 flows and surrounds the radiopaque inner capsule 12 . It will also be appreciated that second openings 22 are not required if the space 28 is evacuated during manufacture. Once the radioactive material has surrounded the inner capsule, the capsule is substantially “activated”.
In a variation of the above, it will be appreciated that some radioactive particles 31 or the isotope 33 may be initially provided outside the inner capsule (on the exterior surface of inner capsule, interior surface of outer capsule, or within space 28 ), such that movement of the radioactive material 30 out of the inner capsule operates to increase, rather than activate, radiation emission by the seed 10 .
Referring now to FIG. 3, according to a second embodiment of the invention, substantially similar to the first embodiment, the radiation therapy seed 110 includes a radiopaque inner capsule (or inner cylinder) 112 provided within a radiotransparent outer capsule 114 . The inner capsule 112 includes first and second ends 116 , 118 , and one or more openings 120 at the first end. A solid, low temperature melting, radioactive material 130 is provided within the inner capsule 112 .
A piston 132 is provided in the inner capsule 112 against the radioactive material 130 , and a pressurized fluid (liquid or gas) 134 is provided between the piston 132 and the second end 118 of the inner capsule urging the piston toward the first end 116 .
Turning now to FIG. 4, the seed 110 may be “activated” by applying heat energy which causes the radioactive material 130 to melt. The pressurized fluid 134 then moves the piston 132 away from the second end 118 , and the piston 132 moves the melted radioactive material 130 through the first openings 120 in the inner capsule into the space 128 between the inner capsule 112 and the outer capsule 114 . Flow of the radioactive material 130 such that the radioactive material surrounds the inner capsule 112 is thereby facilitated.
Referring now to FIG. 5, according to a third embodiment of the invention, the radiation therapy seed 210 includes a capsule 214 having therein a rod 230 formed from a low melting point radioactive material which is provided with an elastic cover 244 , e.g., latex, stretched thereover. Alternatively, the cover may be made from a heat shrinkable material. The cover 244 is provided with a radiopaque coating 226 thereon. The rod 230 and cover 244 preferably substantially fill the interior 246 of the capsule 214 . As such, radiation emission is limited to the ends 248 of the rod.
Turning now to FIG. 6, when the capsule 214 is heated, the rod 230 liquefies and the cover 244 collapses inward to force the radioactive material out from within the cover. The radioactive material 230 thereby surrounds the collapsed cover 244 , with radiopaque material 226 deposited thereon, and increases the radioactive emission by the seed 210 .
Referring now to FIG. 7, according to a fourth embodiment of the invention, the radiation therapy seed 310 includes an inner capsule 312 provided within an outer capsule 314 . The inner capsule 312 includes first and second ends 316 , 318 . The first end 316 includes openings 320 . A high Z material 326 is deposited on a surface 324 of the inner capsule 312 . Alternatively, the inner capsule is made from a high Z material. The inner capsule is preferably coaxially held within the outer capsule, and preferably a vacuum is provided therebetween.
The inner capsule 312 is partially filled with a radioactive material 330 which is liquid at body temperature, e.g., a dissolved radioactive compound. The inner capsule is also provided with a pressurized fluid (gas or liquid) 334 . A piston 332 separates the radioactive material 330 and the pressurized fluid 334 . The liquid material 330 is contained within the inner capsule by a wax plug 346 or the like, which is substantially solid at body temperature and which blocks the passage of the liquid radioactive material 330 through the openings 320 at the first end 316 of the inner capsule 312 .
Turning now to FIG. 8, when the seed 310 is heated, the plug 346 is melted and the pressurized fluid 334 forces the melted plug 346 and radioactive material 330 to exit the openings 320 at the first end 316 of the inner capsule 312 and surround the inner capsule and high Z material 326 thereof such that radiation may be emitted by the seed.
It will be appreciated that as an alternative to a wax plug 346 or the like, a frangible disc or valve may be utilized to retain the liquid radioactive material. The disc or valve may be operated via heat or mechanical means to controllably permit the radioactive material to flow out of the inner capsule.
Referring now to FIG. 9, according to a fifth embodiment of the invention, the radiation therapy seed 410 includes an inner capsule 412 provided within an outer capsule 414 . The inner capsule 412 is preferably held substantially coaxial within the outer capsule by a gas permeable tube 448 , e.g., a mesh or perforate tube formed of a low Z metal or plastic. The inner capsule 412 is comprised of first and second preferably substantially tubular components 450 , 452 , each having a closed end 454 , 456 , respectively, and an open end 458 , 460 , respectively. The open end 458 of the first component 450 is sized to receive therein at least the open end 460 and a portion of the second component 452 . The first and second components 450 , 452 together thereby form a “closed” inner capsule 412 . At least one of the first and second components is provided with a hole 462 which is blocked by the other of the first and second components when the inner capsule is in the “closed” configuration. A gas 434 is provided in the closed inner capsule 412 .
The first component and second components 450 , 452 are made from a substantially low Z material. The second component 452 is provided with a plurality of preferably circumferential bands 464 of a radioactive material, while the first component 450 is provided with a plurality of preferably circumferential bands 466 of a high Z material. The first and second components are fit and aligned together such that along the length of the inner capsule 412 a series of bands in which the radioactive material 464 is covered by the high Z material 466 are provided. The bands 466 of high Z material substantially block the transmission of radiation at the isotope bands 464 .
Turning now to FIG. 10, when the seed 410 is heated, the gas 434 within the inner capsule 412 increases in pressure and forces the second component axially away from the first component such that the volume of the inner capsule increases. As the first and second components 450 , 452 move axially apart, the hole 462 becomes exposed which equalizes the pressure between the interior of the inner capsule 412 and the interior of the outer capsule 414 , terminating the axial movement. The hole 462 is preferably positioned such that movement is terminated with the high Z bands 466 of the first component 450 substantially alternating with the radioactive isotope bands 464 of the second component 452 , such that the seed is activated for radiation emission.
It will be appreciated that the other means may be used to move the first and second components 450 , 452 relative to each other. For example, a one-way inertial system or an electromagnetic system may be used. In addition, it will be appreciated that the inner capsule 412 may be configured such that the high Z bands 466 initially only partially block the radioactive isotope bands 464 ; i.e., that the seed 410 may be activated from a first partially activate state to a second state with increased radioactive emission.
Referring now to FIG. 11, according to a sixth embodiment of the invention, a radiation therapy seed 610 includes an inner wire 612 provided with a circumferential band 676 of radioactive isotope material. A close wound shape memory spring coil 678 is positioned centrally over the inner wire 612 over the band 676 of radioactive material. The shape memory coil 678 is preferably made from a relatively high Z material, e.g., Nitinol, and is trained to expand when subject to a predetermined amount of heat. Second and third spring coils 680 , 682 are positioned on either side of the shape memory coil 678 to maintain the high Z coil 687 at the desired location. Washers 684 may be positioned between each of the coils 678 , 680 , 682 to maintain the separation of the coils; i.e., to prevent the coils from entangling and to better axially direct their spring forces. The wire 612 and coils 678 , 680 , 682 are provided in an outer capsule 614 .
Turning now to FIG. 12, when the seed 610 is subject to a predetermined amount of heat, the shape memory coil 678 expands to substantially expose the isotope band 676 and to thereby activate the seed.
Referring now to FIG. 13, according to a seventh embodiment of the invention, a radiation therapy seed 710 includes a relatively radiotranslucent capsule 714 provided with preferably six rods 786 oriented longitudinally in the capsule 714 . The rods 786 are made from a shape memory material which preferably is substantially radiopaque, e.g., a nickel titanium alloy. Each end of each rod is provided with a twisted portion 787 . In addition, the ends of the rods are secured, e.g., by glue 789 or weld, in the outer capsule 714 . When the rods are subject to heat energy, the rods are adapted to untwist at their respective twisted portions 787 about their respective axes. The rods 786 are each provided with a longitudinal stripe 788 (preferably extending about 60° to 120° about the circumference of the rods) of a radioactive isotope along a portion of their length, and preferably oriented in the capsule 714 such that the stripe 788 of each is directed radially inward toward the center C of the capsule with the high Z material of the rod substantially preventing or limiting transmission of radiation therethrough.
Turning now to FIG. 14, when subject to heat energy, the shape memory rods 786 within the seed 710 twist (or rotate) along their axes. The rods 786 are preferably oriented such that adjacent rods rotate in opposite directions. Turning now to FIG. 15, the rods 786 are trained to rotate preferably 180° about their respective axes. As a result, the isotope stripe 788 along each of the rods 786 is eventually directed radially outward to activate radiation emission by the seed.
It will be appreciated that the rods 786 are not required to be substantially radiopaque and that alternatively, or additionally, the rods may be circumferentially deposited with a relatively high Z material along their length at least diametrically opposite the longitudinal stripes of radioactive isotopes, and preferably at all locations on the rods other than on the stripes 788 . Furthermore, it will be appreciated that fewer than six or more than six rods may be provided in the capsule. Moreover, a central rod may also be used to maintain the rods in the desired spaced apart configuration; i.e., such that the rods together form a generally circular cross section.
Referring now to FIG. 16, according to an eighth embodiment of the invention, a radiation therapy seed 810 includes a relatively radiotranslucent capsule 814 provided with preferably three elongate shape memory strips 890 positioned lengthwise in the capsule 814 . It will be appreciated that two or four or more strips 890 may also be used. The strips are preferably made from Nitinol and are also preferably coated with a high Z material 891 , e.g., gold or a heavy metal, on one side (an initially outer side), and with a radioactive isotope 892 on the side opposite the high Z material (an initially inner side). The strips 890 are preferably positioned in the capsule at 120° relative separation. The configuration of the strips 890 and the high Z material on the outer side of the strips substantially limits radiation emission by the seed, as radiation is emitted only from between the ends of the strips, at 896 .
The shape memory strips 890 are trained to bend. As shown in FIGS. 17 through 19, when heat is applied to the seed, the strips 890 fold into their bent configuration such that eventually the radioactive material 892 of the strips 890 is located substantially on an exterior surface of the strips, while the high Z material is located on an interior side of the strips to further activate the seed. The strips 890 may be coupled to the capsule 814 by posts (not shown) to maintain their relative positions during bending.
There have been described and illustrated herein several embodiments of an activatable radioactive therapeutic seed. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. For example, those skilled in the art will appreciate that certain features of one embodiment may be combined with features of another embodiment to provide yet additional embodiments. Also, while hot water is disclosed as a heat source for “activating” many of the embodiments of the “activatable” seeds, it will be appreciated that microwave technology or other forms of radiated energy transmitted from a distance or provided at or near the seed implant site may also be used to generate sufficient heat. In addition, while a particular preferred temperature range for melting the radioisotope carrier is disclosed, it will be appreciated that a carrier may be used which melts at any temperature at or between body temperature, i.e., approximately 98° F., and an upper temperature which will not cause severe damage to body tissue if applied for a very short period of time, i.e., approximately 212° F. Thus, for example, seeds which are intended to be activated at body temperature are preferably stored at room temperature or kept refrigerated prior to use, but may not be handled by the practitioner without substantial activation. Furthermore, it will be appreciated that other types of energy can be used to trigger partial or complete seed “activation”. For example, mechanical, electromagnetic, and piezoelectric energy can also be used. In addition, while particular dimensions have been disclosed for the seeds, it will be appreciated that other dimensions may be likewise be used depending on the particular application of the seed; i.e., its locus of implantation. Also, it will be appreciated that the terms “radiotransparent”, “radiotranslucent”, “radiolucent”, and “low Z” are intended to have the same meaning for purpose of the prior description and in the construction of the claims which follow. In addition, the above “activatable” embodiments in conjunction with the “deactivatable” embodiments of the previously incorporated parent case, provide a complete system in which the radiation transmission of a brachytherapy seed can be controllably altered. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as so claimed. | An implantable radiation therapy device includes a biocompatible radiotranslucent outer capsule containing a radiation shielding element and a radioactive isotope at least partially shielded by the shielding element. When the device is at or below body temperature, radiation is prevented or limited from being transmitted through the outer capsule by the shielding element. When non-ambient energy is applied to the device, the shielding element and radioactive isotope are reconfigured such that an increased level of radiation is transmitted through the outer capsule and emitted by the device. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. patent application Ser. No. 09/832,739 filed Apr. 11, 2001, now U.S. Pat. No. 6,860,218, entitled “Flexible Fluid Containment Vessel” and which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a flexible fluid containment vessel (sometimes hereinafter referred to as “FFCV”) for transporting and containing a large volume of fluid, particularly fluid having a density less than that of salt water, more particularly, fresh water, and the method of making the same.
BACKGROUND OF THE INVENTION
The use of flexible containers for the containment and transportation of cargo, particularly fluid or liquid cargo, is well known. It is well known to use containers to transport fluids in water, particularly, salt water.
If the cargo is fluid or a fluidized solid that has a density less than salt water, there is no need to use rigid bulk barges, tankers or containment vessels. Rather, flexible containment vessels may be used and towed or pushed from one location to another. Such flexible vessels have obvious advantages over rigid vessels. Moreover, flexible vessels, if constructed appropriately, allow themselves to be rolled up or folded after the cargo has been removed and stored for a return trip.
Throughout the world there are many areas which are in critical need of fresh water. Fresh water is such a commodity that harvesting of the ice cap and icebergs is rapidly emerging as a large business. However, wherever the fresh water is obtained, economical transportation thereof to the intended destination is a concern.
For example, currently an icecap harvester intends to use tankers having 150,000 ton capacity to transport fresh water. Obviously, this involves, not only the cost involved in using such a transport vehicle, but the added expense of its return trip, unloaded, to pick up fresh cargo. Flexible container vessels, when emptied can be collapsed and stored on, for example, the tugboat that pulled it to the unloading point, reducing the expense in this regard.
Even with such an advantage, economy dictates that the volume being transported in the flexible container vessel be sufficient to overcome the expense of transportation. Accordingly, larger and larger flexible containers are being developed. However, technical problems with regard to such containers persist even though developments over the years have occurred. In this regard, improvements in flexible containment vessels or barges have been taught in U.S. Pat. Nos. 2,997,973; 2,998,973; 3,001,501; 3,056,373; and 3,167,103. The intended uses for flexible containment vessels is usually for transporting or storing liquids or fluidisable solids which have a specific gravity less than that of salt water.
The density of salt water as compared to the density of the liquid or fluidisable solids reflects the fact that the cargo provides buoyancy for the flexible transport bag when a partially or completely filled bag is placed and towed in salt water. This buoyancy of the cargo provides flotation for the container and facilitates the shipment of the cargo from one seaport to another.
In U.S. Pat. No. 2,997,973, there is disclosed a vessel comprising a closed tube of flexible material, such as a natural or synthetic rubber impregnated fabric, which has a streamlined nose adapted to be connected to towing means, and one or more pipes communicating with the interior of the vessel such as to permit filling and emptying of the vessel. The buoyancy is supplied by the liquid contents of the vessel and its shape depends on the degree to which it is filled. This patent goes on to suggest that the flexible transport bag can be made from a single fabric woven as a tube. It does not teach, however, how this would be accomplished with a tube of such magnitude. Apparently, such a structure would deal with the problem of seams. Seams are commonly found in commercial flexible transport bags, since the bags are typically made in a patch work manner with stitching or other means of connecting the patches of water proof material together. See e.g. U.S. Pat. No. 3,779,196. Seams are known to be a source of bag failure when the bag is repeatedly subjected to high loads. Seam failure can obviously be avoided in a seamless structure.
Other problems face the use of large transport containers. In this regard, when partially or completely filled flexible barges or transport containers are towed through salt water, problems as to instability are known to occur. This instability is described as a flexural oscillation of the container and is directly related to the flexibility of the partially or completely filled transport container. This flexural oscillation is also known as snaking. Long flexible containers having tapered ends and a relatively constant circumference over most of their length are known for problems with snaking. Snaking is described in U.S. Pat. No. 3,056,373, observing that flexible barges having tapered ends, build up to damaging oscillations capable of seriously rupturing or, in extreme cases, destroying the barge, when towed at a speed above a certain critical speed. Oscillations of this nature were thought to be set up by forces acting laterally on the barge towards its stern. A solution suggested was to provide a device for creating breakaway in the flow lines of the water passing along the surface of the barge and causing turbulence in the water around the stern. It is said that such turbulence would remove or decrease the forces causing snaking, because snaking depends on a smooth flow of water to cause sideways movement of the barge.
Other solutions have been proposed for snaking by, for example, U.S. Pat. Nos. 2,998,973; 3,001,501; and 3,056,373. These solutions include drogues, keels and deflector rings, among others.
Another solution for snaking is to construct the container with a shape that provides for stability when towing. A company known as Nordic Water Supply located in Norway has utilized this solution. Flexible transport containers utilized by this company have a shape that can be described as an elongated hexagon. This elongated hexagon shape has been shown to provide for satisfactory stable towing when transporting fresh water on the open sea. However, such containers have size limitations due to the magnitude of the forces placed thereon. In this regard, the relationship of towing force, towing speed and fuel consumption for a container of given shape and size comes into play. The operator of a tugboat pulling a flexible transport container desires to tow the container at a speed that minimizes the cost to transport the cargo. While high towing speeds are attractive in terms of minimizing the towing time, high towing speeds result in high towing forces and high fuel consumption. High towing forces require that the material used in the construction of the container be increased in strength to handle the high loads. Increasing the strength typically is addressed by using thicker container material. This, however, results in an increase in the container weight and a decrease in the flexibility of the material. This, in turn, results in an increase in the difficulty in handling the flexible transport container, as the container is less flexible for winding and heavier to carry.
Moreover, fuel consumption rises rapidly with increased towing speed. For a particular container, there is a combination of towing speed and fuel consumption that leads to a minimum cost for transportation of the cargo. Moreover, high towing speeds can also exacerbate problems with snaking.
In the situation of the elongated hexagon shaped flexible transport containers used in the transport of fresh water in the open sea, it has been found, for a container having a capacity of 20,000 cubic meters, to have an acceptable combination of towing force (about 8 to 9 metric tons), towing speed (about 4.5 knots) and fuel consumption. Elongated hexagon shaped containers having a capacity of 30,000 cubic meters are operated at a lower towing speed, higher towing force and higher fuel consumption than a 20,000 cubic meter cylindrical container. This is primarily due to the fact that the width and depth of the larger elongated hexagon must displace more salt water when pulled through open sea. Further increases in container capacity are desirable in order to achieve an economy of scale for the transport operation. However, further increases in the capacity of elongated hexagon shaped containers will result in lower towing speeds and increased fuel consumption.
The aforenoted concerning snaking, container capacity, towing force, towing speed and fuel consumption defines a need for an improved flexible transport container design. There exists a need for an improved design that achieves a combination of stable towing (no snaking), high FFCV capacity, high towing speed, low towing force and low fuel consumption relative to existing designs.
In addition, to increase the volume of cargo being towed, it has been suggested to tow a number of flexible containers together. Such arrangements can be found in U.S. Pat. Nos. 5,657,714; 5,355,819; and 3,018,748 where a plurality of containers are towed in line one after another. So as to increase stability of the containers, EPO 832 032 B1 discloses towing multiple containers in a pattern side by side.
However, in towing flexible containers side by side, lateral forces caused by ocean wave motion creates instability which results in one container pushing into the other and rolling end over end. Such movements have a damaging effect on the containers and also effect the speed of travel.
Another problem with such flexible containers is the large towing forces thereon, in addition to the forces created by extreme sea and wind conditions. Accordingly, it is imperative that ruptures in the container be avoided, otherwise the entire cargo could become compromised. Reinforcing the container against such failures is desirable and various means for reinforcing the container have been proposed. These typically include the attachment of ropes to the outer surface of the container, as can be seen in, for example, U.S. Pat. Nos. 2,979,008 and 3,067,712. Reinforcement strips and ribs cemented to the outer surface of the container have also been envisioned, as disclosed in U.S. Pat. No. 2,391,926. Such reinforcements, however, suffer the disadvantages of requiring their attachment to the container while also being cumbersome, especially if the container is intended to be wound up when emptied. Moreover, external reinforcements on the container's surface provide for increased drag during towing. While reinforcements are very desirable, especially if a somewhat light weight fabric is envisioned, the manner of reinforcement needs to be improved upon.
Furthermore, while as aforenoted, a seamless flexible container is desirable and has been mentioned in the prior art, the means for manufacturing such a structure has its difficulties. Heretofore, as noted, large flexible containers were typically made in smaller sections which were sewn or bonded together. These sections had to be water impermeable. Typically such sections, if not made of an impermeable material, could readily be provided with such a coating prior to being installed. The coating could be applied by conventional means such as spraying or dip coating.
For larger coated fabrics (i.e. 40′×200′), it is possible to coat them using a large two roll liquid coating system. Although large, these fabrics are not as large as required for FFCVs. It is economically impractical to build a roll system to coat a fabric of the large size envisioned.
As distinct from the roll system, impermeable fabrics have also traditionally been made by applying a liquid coating to a woven or non-woven base structure and then curing or setting the coating via heat or a chemical reaction. The process involves equipment to tension and support the fabric as the coating is being applied and ultimately cured. For fabrics in the size range of 100″ in width, conventional coating lines are capable of handling many hundreds or thousands of feet. They involve the use of support rolls, coating stations and curing ovens that will handle woven substrates that fall within the 100″ width.
However, with an extremely large flexible woven seamless container, in order of 40′ diameter and 1000′ in length or larger, conventional coating methods would be difficult. While relatively small flat fabrics are readily coated, a tubular unitary structure, extremely long and wide, is much more difficult.
Accordingly, there exist a need for a FFCV for transporting large volumes of fluid which overcomes the aforenoted problems attendant to such a structure and the environment in which it is to operate.
SUMMARY OF THE INVENTION
It is therefore a principal object of the invention to provide for a relatively large seamless woven FFCV for the transportation of cargo, including, particularly, fresh water, having a density less than that of salt water.
It is a further object of the invention to provide for such an FFCV which has means of inhibiting the undesired snaking thereof during towing.
It is a further object of the invention to provide means for allowing the transportation of a plurality of such FFCVS.
A further object of the invention is to provide for a means for reinforcing of such an FFCV so as to effectively distribute the load thereon and inhibit rupture.
A yet further object is to provide for a method of coating the woven tube used in the FFCV or otherwise rendering it impermeable.
These and other objects and advantages will be realized by the present invention. In this regard the present invention envisions the use of a seamless woven tube to create the FFCV, having a length of 300′ or more and a diameter of 40′ or more. Such a large structure can be woven on existing machines that weave papermaker's clothing such as those owned and operated by the assignee hereof. The ends of the tube, sometimes referred to as the nose and tail, or bow and stern, are sealed by any number of means, including being folded over and bonded and/or stitched with an appropriate tow bar attached at the nose. Examples of end portions in the prior art can be found in U.S. Pat. Nos. 2,997,973; 3,018,748; 3,056,373; 3,067,712; and 3,150,627. An opening or openings are provided for filling and emptying the cargo such as those disclosed in U.S. Pat. Nos. 3,067,712 and 3,224,403.
In order to reduce the snaking effect on such a long structure, a plurality of longitudinal stiffening beams are provided along its length. These stiffening beams are intended to be pressurized with air or other medium. The beams are preferably woven as part of the tube but also may be woven separately and maintained in sleeves woven as part of the FFCV. They may also be braided in a manner as set forth in U.S. Pat. Nos. 5,421,128 and 5,735,083 or in an article entitled “3-D Braided Composites-Design and Applications” by D. Brookstein, 6 th European Conference on Composite Materials, September 1995. They can also be knit or laid up as an integral part of the textile structure used to make the tube. The entire structure is preferably made as one piece (unitized construction). Attaching or fixing such beams by sewing is also possible, however, unitized construction is preferred due to the ease of manufacturing and its greater strength.
Stiffening or reinforcement beams of similar construction as noted above may also be provided at spaced distances about the circumference of the tube.
The beams also provide buoyancy to the FFCV as the cargo is unloaded to keep it afloat, since the empty FFCV would normally be heavier than salt water. Valves may be provided which allow pressurization and depressurization as the FFCV is wound up for storage.
In the situation where more than one FFCV is being towed, it is envisioned that one way is that they be towed side by side. To increase stability and avoid “roll over”, a plurality of beam separators, preferably containing pressurized air or other medium, would be used to couple adjacent FFCVs together along their length. The beam separators can be affixed to the side walls of the FFCV by way of pin seam connectors or any other means suitable for purpose.
Another way would be by weaving an endless or seamless series of FFCVs interconnected by a flat woven portion.
In addition, the present invention includes fiber reinforcements woven into the tube used to construct the FFCV. These reinforcement fibers can be spaced in the longitudinal direction about the circumference of the tube and in the vertical direction along the length of the tube. In addition to providing reinforcement, such an arrangement may allow for the use of a lighter weight fabric in the construction of the tube. Since they are woven into the fabric, external means for affixing them are not necessary nor do they create additional drag during towing.
Reinforcement may also take the form of woven pockets in the tube to receive lengthwise and circumferential reinforcing ropes or wires which will address the load requirements on the FFCV while preserving its shape.
The present invention also discloses methods rendering the tube impervious. In this regard various methods are proposed so as to allow for conventional coating to be used, i.e. spray, dip coating, etc. The tube can be coated on the inside, outside, or both with an impervious material. The tube, if the weave is tight enough, may be inflated with the outside spray coated. A non-stick bladder may be inserted, if necessary, to allow the coating of the outside. The bladder is then removed and the tube can be inflated and the inside coated. Alternatively, a flat non-stick liner can be inserted into the tube to prevent the sticking of the interior surface during coating and thereafter it is removed. Also, mechanical means may be inserted within the tube during coating to keep the interior surfaces apart during coating.
Alternatively, the tube may be woven with a fiber having a thermoplastic coating or with thermoplastic fibers interdispersed within the weave. The tube would then be subject to heat and pressure so as to cause the thermoplastic material to fill the voids in the weave and create an impermeable tube. An apparatus that provides for accomplishing this is also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
Thus by the present invention its objects and advantages will be realized, the description of which should be taken in conjunction with the drawings, wherein:
FIG. 1 is a somewhat general perspective view of a prior art FFCV which is cylindrical having a pointed bow or nose;
FIG. 2 is a somewhat general perspective view of a FFCV which is cylindrical having a flattened bow or nose incorporating the teachings of the present invention;
FIG. 2A is a somewhat general perspective view of a tongue arrangement sealing the bow or nose of the FFCV incorporating the teachings of the present invention;
FIG. 2B is a side section view of the bow of the FFCV shown in FIG. 2A incorporating the teachings of the present invention;
FIGS. 2C and 2D show an alternative tongue arrangement to that shown in FIGS. 2A and 2B incorporating the teachings of the present invention;
FIG. 2E is a somewhat general perspective view of a collapsed and folded end portion of the FFCV prior to sealing incorporating the teachings of the present invention;
FIG. 2F is a somewhat general perspective view of a FFCV having blunt end caps on its bow and stern incorporating the teachings of the present invention;
FIGS. 2G and 2H show an alternative end cap arrangement to that shown in FIG. 2F incorporating the teachings of the present invention;
FIG. 2I is a somewhat general perspective view of a FFCV having a flattened bow which is orthogonal to the stern incorporating the teachings of the present invention;
FIG. 3 is a sectional view of a FFCV having longitudinal stiffening beams incorporating the teachings of the present invention;
FIG. 3A is a somewhat general perspective view of a FFCV having longitudinal stiffening beams (shown detached) which are inserted in sleeves along the FFCV incorporating the teachings of the present invention;
FIG. 4 is a partially sectional view of a FFCV having circumferential stiffening beams incorporating the teachings of the present invention;
FIG. 5 is a somewhat general view of a pod shaped FFCV having a longitudinal stiffening beam and a vertical stiffening beam at its bow incorporating the teachings of the present invention;
FIGS. 5A and 5B show somewhat general views of a series of pod shaped FFCVs connected by a flat woven structure, incorporating the teachings of the present invention;
FIG. 6 is a somewhat general view of two FFCVs being towed side by side with a plurality of beam separators connected therebetween incorporating the teachings of the present invention;
FIG. 7 is a somewhat schematic view of the force distribution on side by side FFCVs connected by beam separators incorporating the teachings of the present invention;
FIG. 8 is a perspective view of a device for applying heat and pressure to a tube which is to be used in an FFCV incorporating the teachings of the present invention;
FIG. 9 is a perspective view of the device shown in FIG. 8 in conjunction with the tube incorporating the teachings of the present invention; and
FIGS. 10 , 10 A and 10 B are perspective views of an alternative form of the tube portion of the FFCV having woven pockets for receiving reinforcing members incorporating the teachings of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The proposed FFCV 10 is intended to be constructed of a seamless woven impermeable textile tube. The tube's configuration may vary. For example, as shown in FIG. 2 , it would comprise a tube 12 having a substantially uniform diameter (perimeter) and sealed on each end 14 and 16 . It can also have a non-uniform diameter or non-uniform shape. See FIG. 5 . The respective ends 14 and 16 may be closed, pinched, and sealed in any number of ways, as will be discussed. The resulting coated structure will also be flexible enough to be folded or wound up for transportation and storage.
Before discussing more particularly the FFCV design of the present invention, it is important to take into consideration certain design factors. The even distribution of the towing load is crucial to the life and performance of the FFCV. During the towing process there are two types of drag forces operating on the FFCV, viscous drag and form drag forces. The total force, the towing load, is the sum of the viscous and form drag forces. When a stationary filled FFCV is initially moved, there is an inertial force experienced during the acceleration of the FFCV to constant speed. The inertial force can be quite large in contrast with the total drag force due to the large amount of mass being set in motion. It has been shown that the drag force is primarily determined by the largest cross-section of the FFCV profile, or the point of largest diameter. Once at constant speed the inertial tow force is zero and the total towing load is the total drag force.
As part of this, and in addition thereto, it has been determined that to increase the volume of the FFCV, it is more efficient to increase its length than it is to increase both its length and width. For example, a towing force as a function of towing speed, has been developed for a cylindrically shaped transport bag having a spherically shaped bow and stern. It assumes that the FFCV is fully submersed in water. While this assumption may not be correct for a cargo that has a density less than salt water, it provides a means to estimate relative effects of the FFCV design on towing requirements. This model estimates the total towing force by calculating and adding together two components of drag for a given speed. The two components of drag are viscous drag and form drag. The formulae for the drag components are shown below.
Viscous Drag (tons)=(0.25*( A 4+ D 4)*( B 4+(3.142 *C 4))* E 4^1.63/8896
Form Drag (tons)=((( B 4−(3.14 *C 4/2))* C 4/2)^1.87)* E 4^1.33*1.133/8896
Total towing force (tons)=Viscous drag (tons)+Form drag (tons)
where A 4 is the overall length in meters, D 4 is the total length of the bow and stern sections in meters, B 4 is the perimeter of the bag in meters, C 4 is the draught in meters and E 4 is the speed in knots.
The towing force for a series of FFCV designs can now be determined. For example, assume that the FFCV has an overall length of 160 meters, a total length of 10 meters for the bow and stern sections, a perimeter of 35 meters, a speed of 4 knots and the bag being filled 50%. The draught in meters is calculated assuming that the cross sectional shape of the partially filled FFCV has a racetrack shape. This shape assumes that the cross section looks like two half circles joined to a rectangular center section. The draught for this FFCV is calculated to be 3.26 meters. The formula for the draught is shown below.
Draught (meters)= B 4/3.14*(1−((1− J 4)^0.5))
where J 4 is the fraction full for the FFCV (50% in this case).
For this FFCV the total drag is 3.23 tons. The form drag is 1.15 tons and the viscous drag is 2.07 tons. If the cargo was fresh water, this FFCV would carry 7481 tons at 50% full.
If one desires a FFCV that can carry about 60,000 tons of water at 50% full, the FFCV capacity can be increased in at least two ways. One way is to scale up the overall length, total length of the bow and stern sections and perimeter by an equal factor. If these FFCV dimensions are increased by a factor of 2, the FFCV capacity at 50% full is 59,846 tons. The total towing force increases from 3.23 tons for the prior FFCV to 23.72 tons for this FFCV. This is an increase of 634%. The form drag is 15.43 tons (an increase of 1241%) and the viscous drag is 8.29 tons (an increase of 300%). Most of the increase in towing force comes from an increase in the form drag which reflects the fact that this design requires more salt water to be displaced in order for the FFCV to move through the salt water.
An alternative means to increase the capacity to 60,000 tons is to lengthen the FFCV while keeping the perimeter, bow and stern dimensions the same. When the overall length is increased to 1233.6 meters the capacity at 50% fill is 59,836 tons. At a speed of 4 knots the total drag force is 16.31 tons or 69% of the second FFCV described above. The form drag is 1.15 tons (same as the first FFCV) and the viscous drag is 15.15 tons (an increase of 631% over the first FFCV).
This alternative design (an elongated FFCV of 1233.6 meters) clearly has an advantage in terms of increasing capacity while minimizing any increase in towing force. The elongated design will also realize much greater fuel economy for the towing vessel relative to the first scaled up design of the same capacity.
With the preferred manner of increasing the volume of the FFCV having been determined, we turn now to the general construction of the tube 12 which will make up the FFCV. The present invention envisions weaving the tube 12 in a seamless fashion on a large textile loom of the type typically used for weaving seamless papermaker's cloth or fabric. The tube 12 is woven on a loom having a width of about 96 feet. With a loom having such a width, the tube 12 would have a diameter of approximately 92 feet. The tube 12 could be woven to a length of 300 feet or more. The tube as will be discussed will have to be impervious to salt water or diffusion of salt ions. Once this is done, the ends of the tubes are sealed. Sealing is required not only to enable the structure to contain water or some other cargo, but also to provide a means for towing the FFCV.
Sealing can be accomplished in many ways. The sealed end can be formed by collapsing the end 14 of the tube 12 and folded over one or more times as shown in FIG. 2 . One end 14 of the tube 12 can be sealed such that the plane of the sealed surface is, either in the same plane as the seal surface at the other end 16 of the tube. Alternatively, end 14 can be orthogonal to the plane formed by the seal surface at the other end 16 of the tube, creating a bow which is perpendicular to the surface of the water, similar to that of a ship. (See FIG. 2I ). For sealing the ends 14 and 16 of the tube are collapsed such that a sealing length of a few feet results. Sealing is facilitated by gluing or sealing the inner surfaces of the flattened tube end with a reactive material or adhesive. In addition, the flattened ends 14 and 16 of the tube can be clamped and reinforced with metal or composite bars 18 that are bolted or secured through the composite structure. These metal or composite bars 18 can provide a means to attach a towing mechanism 20 from the tugboat that tows the FFCV.
In addition, as shown in FIGS. 2A and 2B , a metal or composite article, which will be called a tongue 22 , can be inserted into and at the end of the tube 12 prior to sealing. The tongue 22 would be contoured to match the shape of the tube end when the tube end is either fully open, partially collapsed, or fully collapsed. The end 14 of the tube 12 would be sealed around the tongue with an adhesive or glue. The tongue would be secured in place with bolts 24 or some other suitable means. The tongue would be bolted not only to the end of the coated tube, but also to any exterior metal plate or composite support device. The tongue could also be fitted with fixtures for towing the FFCV. The tongue could also be fitted with one or more ports or pipes 28 that can be used to either vent the FFCV, fill the FFCV with water, or empty the FFCV of water. These pipes can be made such that pumps connected to a discharge pipe and external power supply can be inserted into the FFCV and be used to empty the FFCV of water.
Other configurations for the construction of the tongue are possible such as the five prong tongue 22 ′ shown in FIGS. 2C and 2D . The tongue 22 ′ would be similarly attached to the tube 12 as discussed with each of the prongs having ports 28 ′ for filling, emptying, or venting. As with each tongue arrangement, it is sized to have an outer surface perimeter to match that of the end of the tube 12 .
An alternative to a tongue arrangement is a pin seam structure that can be created in the sealed end. A way to do this is to make use of the lead and trailing edges of the FFCV to form seams such as a pin seam. A pin seam could be made by starting off the weaving of the tube by first weaving a flat fabric for a length of about 10 feet. The loom configuration would then be changed to transition into a tubular fabric and then at the opposite end changed back to a flat fabric for about 10 feet. After coating the flat end of the tube, it is folded back onto itself to form a closed loop. This loop would be fixed in place by fastening together the two pieces of coated fabric that come in contact to form the loop. These pieces could be fastened with bolts and reinforced with a composite or metal sheet. The closed loop would be machined or cut such that it formed a series of equally sized, looped fingers with spaces between the fingers. These spaces would have a width slightly larger than the width of a looped finger. The looped fingers form one end of a pin seam that can be meshed with another set of looped fingers from another FFCV. Once the looped fingers are meshed from the two ends of two FFCVs, a rope or pintle would be inserted in the loops and fixed in place. This pin seam can be used for attaching a towing mechanism. Alternatively, it can provide a means for joining together two FFCVs. The two FFCVs can be joined together quickly and disconnected quickly by this means of joining.
An alternative to forming a simple collapsed and sealed end involves both collapsing and folding the end 14 of the tube 12 such that the width W of the sealed end matches either the diameter of the tube or the width of the tube when the tube is filled with water and floated in sea water. The general configuration of the collapsed and folded end is shown in FIG. 2E . This feature of matching the width of the sealed end with either the width of the tube or diameter of the tube as filled will minimize stress concentration when the FFCV is being towed.
The end 14 (collapsed and folded) will be sealed with a reactive polymer sealant or adhesive. The sealed end can also be reinforced as previously discussed with metal or composite bars to secure the sealed end and can be provided with a means for attaching a towing device. In addition, a metal or composite tongue, as discussed earlier, can be inserted into and at the end of the tube prior to sealing. The tongue would be contoured to match the shape of the tube end when the tube end is collapsed and folded.
Another means for sealing the ends involves attaching metal or composite end caps 30 as shown in FIG. 2F . In this embodiment, the size of the caps will be determined by the perimeter of the tube. The perimeter of the end cap 30 will be designed to match the perimeter of the inside of the tube 12 and will be sealed therewith by gluing, bolting or any other means suitable for purpose. The end cap 30 will serve as the sealing, filling/emptying via ports 31 , and towing attachment means. The FFCV is not tapered, rather it has a more “blunt” end with the substantially uniform perimeter which distributes the force over the largest perimeter, which is the same all along the length, instead of concentrating the forces on the smaller diameter, neck area of prior art FFCV (see FIG. 1 ). By attaching a tow cap that matches the perimeter it ensures a more equal distribution of forces, particularly start up towing forces, over the entire FFCV structure.
An alternative design of an end cap is shown in FIGS. 2G and 2H . The end cap 30 ′ shown is also made of metal or composite material and is glued, bolted or otherwise sealed to tube 12 . As can be seen, while being tapered, the rear portion of cap 30 ′ has a perimeter that matches the inside perimeter of the tube 12 which provides for even distribution of force thereon.
The collapsed approach, the collapsed and folded configuration for sealing, the tongue approach, or the end cap approach can be designed to distribute, rather than concentrate, the towing forces over the entire FFCV and will enable improved operation thereof.
Having already considered towing forces to determine the shape which is more efficient i.e. longer is better than wider, and the means for sealing the ends of the tube, we turn now to a discussion of the forces on the FFCV itself in material selection and construction.
The forces that may occur in a FFCV can be understood from two perspectives. In one perspective, the drag forces for a FFCV traveling through water over a range of speeds can be estimated. These forces can be distributed evenly throughout the FFCV and it is desirable that the forces be distributed as evenly as possible. Another perspective is that the FFCV is made from a specific material having a given thickness. For a specific material, the ultimate load and elongation properties are known and one can assume that this material will not be allowed to exceed a specific percentage of the ultimate load. For example, assume that the FFCV material has a basis weight of 1000 grams per square meter and that half the basis weight is attributed to the textile material (uncoated) and half to the matrix or coating material with 70% of the fiber oriented in the lengthwise direction of the FFCV. If the fiber is, for example, nylon 6 or nylon 6.6 having a density of 1.14 grams per cubic centimeter, one can calculate that the lengthwise oriented nylon comprises about 300 square millimeters of the FFCV material over a width of 1 meter. Three hundred (300) square millimeters is equal to about 0.47 square inches. If one assumes that the nylon reinforcement has an ultimate breaking strength of 80,000 pounds per square inch, a one meter wide piece of this FFCV material will break when the load reaches 37,600 lbs. This is equivalent to 11,500 pounds per lineal foot. For a FFCV having a diameter of 42 ft. the circumference is 132 ft. The theoretical breaking load for this FFCV would be 1,518,000 lbs. Assuming that one will not exceed 33% of the ultimate breaking strength of the nylon reinforcement, then the maximum allowable load for the FFCV would be about 500,000 lbs or about 4,000 pounds per lineal foot (333 pounds per lineal inch). Accordingly, load requirement can be determined and should be factored into material selection and construction techniques.
Also, the FFCV will experience cycling between no load and high load. Accordingly, the material's recovery properties in a cyclical load environment should also be considered in any selection of material. The materials must also withstand exposure to sunlight, salt water, salt water temperatures, marine life and the cargo that is being shipped. The materials of construction must also prevent contamination of the cargo by the salt water. Contamination would occur, if salt water were forced into the cargo or if the salt ions were to diffuse into the cargo.
With the foregoing in mind, the present invention envisions FFCVs being constructed from coated textiles. Coated textiles have two primary components. These components are the fiber reinforcement and the polymeric coating. A variety of fiber reinforcements and polymeric coating materials are suitable for FFCVs. Such materials must be capable of handling the mechanical loads and various types of extensions which will be experienced by the FFCV.
The present invention envisions a breaking tensile load that the FFCV material should be designed to handle in the range from about 1100 pounds per inch of fabric width to 2300 pounds per inch of fabric width. In addition, the coating must be capable of being folded or flexed repeatedly as the FFCV material is frequently wound up on a reel.
Suitable polymeric coating materials include polyvinyl chloride, polyurethanes, synthetic and natural rubbers, polyureas, polyolefins, silicone polymers and acrylic polymers. These polymers can be thermoplastic or thermoset in nature. Thermoset polymeric coatings may be cured via heat, room temperature curable or UV curable. The polymeric coatings may include plasticizers and stabilizers that either add flexibility or durability to the coating. The preferred coating materials are plasticized polyvinyl chloride, polyurethanes and polyureas. These materials have good barrier properties and are both flexible and durable.
Suitable fiber reinforcement materials are nylons (as a general class), polyesters (as a general class), polyaramids (such as Kevlar®, Twaron or Technora), polyolefins (such as Dyneema and Spectra) and polybenzoxazole (PBO).
Within a class of material, high strength fibers minimize the weight of the fabric required to meet the design requirement for the FFCV. The preferred fiber reinforcement materials are high strength nylons, high strength polyaramids and high strength polyolefins. PBO is desirable for it's high strength, but undesirable due to its relative high cost. High strength polyolefins are desirable for their high strength, but difficult to bond effectively with coating materials.
The fiber reinforcement can be formed into a variety of weave constructions. These weave constructions vary from a plain weave (1×1) to basket weaves and twill weaves. Basket weaves such as a 2×2, 3×3, 4×4, 5×5, 6×6, 2×1, 3×1, 4×1, 5×1 and 6×1 are suitable. Twill weaves such as 2×2, 3×3, 4×4, 5×5, 6×6, 2×1, 3×1, 4×1, 5×1 and 6×1 are suitable. Additionally, satin weaves such as 2×1, 3×1, 4×1, 5×1 and 6×1 can be employed. While a single layer weave has been discussed, as will be apparent to one skilled in the art, multi-layer weaves might also be desirable, depending upon the circumstances.
The yarn size or denier in yarn count will vary depending on the strength of the material selected. The larger the yarn diameter the fewer threads per inch will be required to achieve the strength requirement. Conversely, the smaller the yarn diameter the more threads per inch will be required to maintain the same strength. Various levels of twist in the yarn can be used depending on the surface desired. Yarn twist can vary from as little as zero twist to as high as 20 turns per inch and higher. In addition, yarn shapes may vary. Depending upon the circumstances involved, round, elliptical, flattened or other shapes suitable for the purpose may be utilized.
Accordingly, with all of the foregoing in mind, the appropriate fiber and weave may be selected along with the coating to be used.
Returning now, however, to the structure of the FFCV 10 itself, while it has been determined that a long structure is more efficiently towed at higher speeds (greater than the present 4.5 knots), snaking in such structures is, however, a problem. To reduce the occurrence of snaking, the present invention provides for an FFCV 10 constructed with one or more lengthwise or longitudinal beams 32 that provide stiffening along the length of the tube 12 as shown in FIG. 3 . In this way a form of structural lengthwise rigidity is added to a FFCV 10 . The beams 32 may be airtight tubular structures made from coated fabric. When the beam 32 is inflated with pressurized gas or air, the beam 32 becomes rigid and is capable of supporting an applied load. The beam 32 can also be inflated and pressurized with a liquid such as water or other medium to achieve the desired rigidity. The beams 32 can be made to be straight or curved depending upon the shape desired for the application and the load that will be supported.
The beams 32 can be attached to the FFCV 10 or, they can be constructed as an integral part of the FFCV. In FIG. 3 , two beams 32 , oppositely positioned, are shown. The beams 32 can extend for the entire length of the FFCV 10 or they can extend for just a short portion of the FFCV 10 . The length and location of the beam 32 is dictated by the need to stabilize the FFCV 10 against snaking. The beams 32 can be in one piece or in multiple pieces 34 that extend along the FFCV 10 (see FIG. 4 ).
Preferably the beam 32 is made as an integral part of the FFCV 10 . In this way the beam 32 is less likely to be separated from the FFCV 10 . One or more beams 32 can be woven as an integral part of a single woven tube 12 for the FFCV 10 . It is possible to not only weave the tube 12 that becomes the cargo carrying space, but also simultaneously weave the tubular structure or structures that become the beam or beams 32 in the FFCV 10 . Note that even in the situation where the stiffening beam is an integral part of the FFCV 10 , it may still be woven of a different material or different weave than the FFCV 10 , as will be apparent to the skilled artisan.
It might also, however, be desirable to make the inflatable stiffening beams 33 as separate units and, as shown in FIG. 3A . The tubular structure could have integrally woven sleeves 35 to receive the stiffening beams 33 . This allows for the stiffening beams to be made to meet different load requirements than the tubular structure. Also, the beam may be coated separately from the FFCV to render it impermeable and inflatable, allowing for a different coating for the tubular structure to be used, if so desired.
Similar beams 36 can also be made to run in the cross direction to the length of the FFCV 10 as shown in FIG. 4 . The beams 36 that run in the cross direction can be used to create deflectors along the side of the FFCV 10 . These deflectors can break up flow patterns of salt water along the side of the FFCV 10 , which, according to the prior art, leads to stable towing of the FFCV 10 . See U.S. Pat. No. 3,056,373.
In addition, the beams 32 and 36 , filled with pressurized air, provide buoyancy for the FFCV 10 . This added buoyancy has limited utility when the FFCV 10 is filled with cargo. This added buoyancy has greater utility when the cargo is being emptied from the FFCV 10 . As the cargo is removed from the FFCV 10 , the beams 32 and 36 will provide buoyancy to keep the FFCV 10 afloat. This feature is especially important when the density of the FFCV 10 material is greater than salt water. If the FFCV 10 is to be wound up on a reel as the FFCV 10 is emptied, the beams 32 and 36 can be gradually deflated via bleeder valves to simultaneously provide for ease of winding and flotation of the empty FFCV 10 . The gradually deflated beams 32 can also act to keep the FFCV 10 deployed in a straight fashion on the surface of the water during the winding, filling and discharging operation.
The placement or location of the beams 32 on the FFCV 10 is important for stability, durability and buoyancy of the FFCV 10 . A simple configuration of two beams 32 would place the beams 32 equidistant from each other along the side of the FFCV 10 as shown in FIG. 3 . If the cross sectional area of beams 32 is a small fraction of the total cross sectional area of the FFCV 10 , then the beams 32 will lie below the surface of the salt water when the FFCV 10 is filled to about 50% of the total capacity. As a result the stiffening beams 32 will not be subjected to strong wave action that can occur at the surface of the sea. If strong wave action were to act on the beams 32 , it is possible that the beams 32 would be damaged. Damage to the beams 32 would be detrimental to the durability of the FFCV 10 . Accordingly, it is preferable that the beams 32 are located below the salt water surface when the FFCV 10 is filled to the desired carrying capacity. These same beams 32 will rise to the surface of the salt water when the FFCV 10 is emptied as long as the combined buoyancy of the beams 32 and 36 is greater than any negative buoyancy force that would cause an empty FFCV 10 to sink.
The FFCV 10 can also be made stable against rollover by placing beams in such a way that the buoyancy of the beams counteracts rollover forces. One such configuration is to have three beams. Two beams 32 would be filled with pressurized gas or air and located on the opposite sides of the FFCV 10 . The third beam 38 would be filled with pressurized salt water and would run along the bottom of the FFCV 10 like a keel. If this FFCV 10 were subjected to rollover forces, the combined buoyancy of the side beams 32 and the ballast effect of the bottom beam 38 would result in forces that would act to keep the FFCV 10 from rolling over.
As aforesaid, it is preferable that the beams be an integral part of the structure of the FFCV. The weaving process therefore calls for weaving multiple tubes that are side by side with each tube having dimensions appropriate to the function of the individual tube. In this way it is possible to weave the structure as a unitized or one piece structure. A high modulus fibrous material in the weave for the beams would enhance the stiffening function of the beams. The woven structure can be coated after weaving to create the barriers to keep air, fresh water and salt water separate from each other.
The beams can also be made as separate woven, laid up, knit, nonwoven or braided tubes that are coated with a polymer to allow them to contain pressurized air or water. (For braiding, see U.S. Pat. Nos. 5,421,128 and 5,735,083 and an article entitled “3-D Braided Composite-Design and Applications” by D. Brookstein, 6 th European Conference on Composite Materials (September 1993).) If the beam is made as a separate tube, the beam must be attached to the main tube 12 . Such a beam can be attached by a number of means including thermal welding, sewing, hook and loop attachments, gluing or pin seaming.
The FFCV 10 can also take a pod shape 50 such as that shown in FIG. 5 . The pod shape 50 can be flat at one end 52 or both ends of the tube while being tubular in the middle 54 . As shown in FIG. 5 , it may include stiffening beams 56 as previously discussed along its length and, in addition, a beam 58 across its end 52 which is woven integrally or woven separately and attached.
The FFCV can also be formed in a series of pods 50 ′ woven endless or seamless, as shown in FIGS. 5A and 5B . In this regard, the pods 50 ′ can be created by weaving a flat portion 51 , then the tubular portion 53 , than flat 51 , then tubular 53 , and so on as shown in FIG. 5A . The ends can be sealed in an appropriate manner discussed herein. In FIG. 5B there is also shown a series of pods 50 ′ so formed, however, interconnecting the tubular portions 53 and woven therewith as part of the flat portions 51 , is a tube 55 which allows the pods 50 ′ to be filled and emptied.
Similar type beams have further utility in the transportation of fluids by FFCVs. In this regard, it is envisioned to transport a plurality of FFCVs together so as to, among other things, increase the volume and reduce the cost. Heretofore it was known to tow multiple flexible containers in tandem, side by side or in a pattern. However, in towing FFCVs side by side, there is a tendency for the ocean forces to cause lateral movement of one against the next or rollover. This may have a damaging effect on the FFCV among other things. To reduce the likelihood of such an occurrence, beam separators 60 , of a construction similar to the beam stiffeners previously discussed, are coupled between the FFCVs 10 along their length as shown in FIG. 6 .
The beam separators 60 could be attached by a simple mechanism to the FFCVs 10 such as by a pin seam or quick disconnect type mechanism and would be inflated and deflated with the use of valves. The deflated beams, after discharging the cargo, could be easily rolled up.
The beam separators 60 will also assist in the floatation of the empty FFCVs 10 during roll up operations, in addition to the stiffening beams 32 , if utilized. If the latter was not utilized, they will act as the primary floatation means during roll up.
The beam separators 60 will also act as a floatation device during the towing of the FFCVs 10 reducing drag and potentially provide for faster speeds during towing of filled FFCVs 10 . These beam separators will also keep the FFCV 10 in a relatively straight direction avoiding the need for other control mechanisms during towing.
The beam separators 60 make the two FFCVs 10 appear as a “catamaran”. The stability of the catamaran is predominantly due to its two hulls. The same principles of such a system apply here.
Stability is due to the fact that during the hauling of these filled FFCVs in the ocean, the wave motion will tend to push one of the FFCVs causing it to roll end-over-end as illustrated in FIG. 7 . However, a counter force is formed by the contents in the other FFCV and will be activated to nullify the rollover force generated by the first FFCV. This counter force will prevent the first FFCV from rolling over as it pushes it in the opposite direction. This force will be transmitted with the help of the beam separators 60 thus stabilizing or self correcting the arrangement.
As has been discussed, it is important to distribute as evenly as possible the forces acting on the FFCV 10 . Much of the prior art focuses especially, on the towing forces and provides for longitudinal reinforcements. This is typically addressed by providing reinforcing ropes or strips on the outside of the FFCV.
The present invention is intended to provide an improved and lower-cost option for reinforcement of FFCVs. The present invention is somewhat analogous to what is known as rip-stop fabric where the fabric is provided with reinforcement at predetermined intervals with larger and/or stronger yarn than that used in the rest of the fabric. A typical example of this is how parachutes are constructed. Such a structure not only provides for strength and tear resistance, but may allow for the reduction of the overall weight of the fabric.
In this regard, as illustrated in FIG. 2F , the present invention involves weaving tensile members 70 and 72 into the fabric of the FFCV, in at least one, but preferably both, principal fabric directions at predetermined intervals of possible one to three feet. While both directions are preferable, they need not be of the same strength in both fabric directions. A greater strength contribution may be required in the fore and aft direction. The tensile members may be larger yarns, and/or yarns of greater specific strength (strength per unit weight or unit cross-section) (e.g. Kelvar®, etc.), than the yarns that comprise most of the body of the tube. The member may be woven singly, at intervals as described, or in groups, at intervals. The reinforcing tensile members may also be rope or braid, for example.
The integrally woven tensile members 70 and 72 of the invention will reduce FFCV 10 costs by greatly simplifying fabrication. All steps associated with measuring, cutting, and attaching reinforcing members will be eliminated. The integrally woven reinforcements 70 and 72 will also contribute more to the overall structural integrity of FFCVs because they can be located optimally without regard for fabrication details. In addition to contributing the desired tensile strength, the integrally woven members 70 and 72 will improve tear resistance and reduce the probability of failure or failure propagation upon impact with floating debris.
A skilled worker in the art will appreciate the selection of the reinforcement material used and the intervals or spacing selected will depend upon, among other things, the towing forces involved, the size of the FFCV, the intended cargo and amount thereof, hoop stresses, along with cost factors and the desired results. Implementation and incorporation of the reinforcing material into the integral weave may be accomplished by existing weaving technology known, for example, in the papermaking cloth industry.
An alternative manner of reinforcing the FFCV is that shown in FIGS. 10-10B . In this regard the FFCV may be formed out of a woven fabric 100 which may be woven flat as shown in FIG. 10 . In such a case, the fabric 100 would ultimately be joined together to create a tube with an appropriate water tight seam along its length. Any seam suitable for purpose may be utilized such as a water tight zipper, a foldback seam, or a pin seam arrangement, for example. Alternatively, it may be woven tubular as shown in FIG. 10A . The fabric would be impermeable and have suitable end portions as have been described with regard to other embodiments herein.
As distinct therefrom, the fabric 100 would include woven pockets 102 which can be along its length, circumference, or both. Contained within the pockets 102 would be suitable reinforcement elements 104 and 106 such as rope, wire or other type suitable for the purpose. The number of pockets and spacing would be determined by the load requirements. Also, the type and size of the reinforcement elements 104 and 106 which are placed in the pockets 102 can be varied depending upon the load (e.g. towing force, hoop stress, etc.). The longitudinal reinforcing element 104 would be coupled at their ends to suitable end caps or tow bars, for example. The radial or circumferential reinforcing elements 106 would have their respective ends suitably joined together by clamping, braiding or other means suitable for the purpose.
By the foregoing arrangement, the load on the FFCV is principally on the reinforcing elements 104 and 106 with the load on the fabric being greatly reduced, thus allowing for, among other things, a lighter weight fabric. Also, the reinforcing elements 104 and 106 will act as rip stops so as to contain tears or damage to the fabric.
As shown in FIG. 10B , an FFCV can be fabricated in sections 110 and 112 and constructed with the pockets 102 aforedescribed. These sections 110 and 112 can then be joined together by way of loops 114 placed at the ends thereof to create a type of pin seam which would then be rendered impervious by way of a coating thereof. A water impermeable zipper may also be used, in addition to any other fabric joining technique suitable for the purpose such as a foldback seam or other seams used in, for example, the papermaking industry. In addition, the respective reinforcing members 104 would be coupled together in a suitable manner so as to convey the load therebetween.
Turning now to a method of rendering such a large structure impermeable, there are several ways to accomplish this.
One means for coating does not require that the inner surface of the tube be accessible. This means would utilize an inexpensive film or liner (such as polyethylene). This film or non-stick liner would be inserted in the inner surface of the tube during the weaving process. This can be done by stopping the loom during weaving of the tubular section and inserting the film into the tube via access gained between warp yarns located between the already woven fabric and the beat-up bar of the loom. This insertion process would probably have to be repeated many times during the weaving process in order to line the inner surface of the tube. Once the film has been inserted on the inside surface of the tube, the structure is sealed and the entire structure can be dip coated; spray coated or coated by some other means such that the woven base fabric is impregnated with the desired coating. The resin-impregnated structure is cured to an extent such that, via an opening cut in the tube surface, the film can be removed, the tube partially or totally inflated via pressurized air, and the curing process completed, if required. The film serves to prevent the coating resin from adhering one inner surface of the tube to another inner surface of the tube.
Another method for coating the tube is to dip coat or spray coat the entire structure without any provision being made for preventing the inner surfaces of the tube from contacting each other i.e., without lining the inner surface of the tube with a film or liner. It is possible to weave a structure such that the coating does not pass completely through the fabric, yet the coating penetrates the woven fabric such that the coating adheres to the fabric. This approach allows one to coat the structure and create a coated tube without concern for the inner surfaces adhering to each other.
Another approach involves the use of a fabric design in which the coating passes through the fabric and the inner surfaces do bond to each other upon coating. In this case, one would insert a manhole size piece of metal or plastic film between the inner surfaces of the tube before coating and before or after sealing the ends of the tube. If after, this piece of metal or plastic film would be inserted through a small hole cut in the woven tube. After coating one would insert or connect a pressurized air line to the space or gap created between the metal or plastic film and a coated surface of the tube. This pressurized air would be used to force the two inner surfaces of the tube away from each other i.e., expand the tube. In doing so the coating that bonds the two inner surfaces would fail in a peeling fashion until the entire inner surfaces of the tube are freed from each other. This approach requires a coating resin that can readily fail in a peeling mode of failure. While coating resins are usually designed to resist peeling, curable resins are susceptible to peeling failure when they are only partially cured. The present invention envisions a process whereby the tubular structure is coated, the coating is partially cured such that the coating no longer flows, forces are then applied while the coating is susceptible to peeling failure such that the inner surfaces are freed from each other. If desired, the inside of the expanded tube may now also be coated.
A further method for coating the tube is to spray coat the structure while making some provision to make sure that the inner surfaces of the tube are not in contact with each other. One way to do this is to inflate the tube with air and coat the structure while air holds the inner surfaces apart. This method depends upon the woven structure having a low permeability to air such that the tube can be inflated by inserting a pressurized air line into the tube. Alternatively, one can erect a scaffold within the tube. Such a scaffold might be a metal support structure or a rigid or semi-rigid tube or slinky type structure (with or without a membrane thereabouts) which will approximate the diameter of the inside of the tube and may be sized to allow it to be movable from section to section that is being coated. The scaffold could also be an inflatable arch or tube that is placed inside the tube. Such scaffolds would be placed inside the tube via a manhole sized access point that is cut in the woven tube surface. Once the scaffold is in place, it may be suitable to spray coat the structure from the outside of the tube, the inside of the tube, or both the inside and outside of the tube.
Note that the inflated arch or tube method may actually use the stiffening beams discussed previously. In this regard, such beams could be first made impermeable by being coated and then inflated to support the tube's expanded shape. Coating of the tube's both inner and outer surface can then be accomplished.
A still further method of coating is envisioned. In this regard, an elastic bladder having an outer circumference slightly less than the inner circumference of the tube is fabricated from an impermeable material. It's axial length would be equal to part or whole of the length of the tube. The outer surface of the bladder would have the characteristics of “release or non-adherence” to the resin or other material that will be used to coat and/or impregnate the tube. This can be accomplished by selecting the proper material for the bladder itself or applying a coating on the outside of the bladder. The bladder is placed inside the tube and is then inflated using a gas or liquid so it expands against the inner surface of the tube. The circumference of the bladder when inflated is such that it would apply circumferential tension to the tube along the full axial length of the bladder. A coating can then be applied to the exterior of the tube in the area where it is held under circumferential tension by the bladder. Hand application, spraying, or any other known application technique can be used to apply the coating. If the bladder axial length is less than the axial length of the tube, the bladder can be deflated after application of the coating and relocated to an uncoated length of the tube and the steps are repeated. Due to the “release or non-adherence” surface, the bladder does not “stick” to the coating that may pass through the tube. After the entire circumferential and axial length of the tube has been coated, the bladder is removed. At this point, if it is desired to coat the inside of the tube, the tube can be assembled and sealed at its ends and inflated. The inside of the tube can now be coated. Note, in all cases where the tube is coated on the inside and outside, the coatings used for each should be compatible to create proper bonding.
A yet further method for coating the tube employs a thermoplastic composite approach. In this approach the tube is woven from a mixture of at least two fibrous materials. One material would be the reinforcing fiber and the second material would be a low melting fiber or low melting component of a reinforcing fiber. The low melting fiber or component might be a thermoplastic polyurethane or polyethylene. The reinforcing fiber might be polyester or nylon tire cord or one of the other fiber hereinbefore discussed. The tube would be subjected to heat and pressure in a controlled fashion. This heat and pressure would cause the low melting fiber or component to melt and fill the void in the woven structure. After the heat and pressure are removed and the structure is cooled, a composite structure would form in which the low melting fiber or component has become the matrix for the reinforcing fiber. This approach requires applying heat and pressure while also providing a means to keep the inner surfaces of the tube from adhering or thermally bonding to each other.
FIGS. 8 and 9 show a device 71 which can apply heat and pressure to the tube 12 . The device 71 can be self-propelled or can be moved by external pulling cables. Each section 73 and 74 of the device includes heating or hot plates with respective magnets 76 and motors (not shown) and are positioned on either side of the fabric as shown in FIG. 9 . A power supply (not shown) is provided to energize the heating plates 76 and supply power to the motors that propel the device across the tube 12 . The magnets serve to pull the two hot plates 76 together which creates pressure to the fabric as the coating on the yarn liquefies from the heat. These magnets also keep the top heating plate 76 opposite to the inside heating plate 76 . The device 71 includes endless non-stick belts 78 that ride on rollers 80 located at the plate ends. The belts 78 ride over the plates 76 . In this way there is no movement of the belt 78 in relation to the fabric surface when it is in contact with the fabric. This eliminates smearing of the melted coating and uniform distribution between the yarns. The device moves across the length of the tube 12 at a speed that enables the melted coat to set prior to the fabric folding back upon itself and sticking. If faster speeds are desired, a means for temporarily keeping the inside surfaces apart while setting takes place, may be implemented. This may be, for example, a trailing member on the inside of the tube of similar design to that described but being only one section without, of course, a heating plate or magnet. Other means suitable for this purpose will be readily apparent to those skilled in the art.
As part of the coating process there is envisioned the use of a foamed coating on the inside or outside or both surfaces of the tube. A foamed coating would provide buoyancy to the FFCV, especially an empty FFCV. An FFCV constructed from materials such as, for example, nylon, polyester and rubber would have a density greater than salt water. As a result the empty FFCV or empty portions of the large FFCV would sink. This sinking action could result in high stresses on the FFCV and could lead to significant difficulties in handling the FFCV during filling and emptying of the FFCV. The use of a foam coating provides an alternative or additional means to provide buoyancy to the FFCV to that previously discussed.
Also, in view of the closed nature of the FFCV, if it is intended to transport fresh water, as part of the coating process of the inside thereof, it may provide for a coating which includes a germicide or a fungicide so as to prevent the occurrence of bacteria or mold or other contaminants.
In addition, since sunlight also has a degradation effect on fabric, the FFCV may include as part of its coating or the fiber used to make up the FFCV, a UV protecting ingredient in this regard.
Although preferred embodiments have been disclosed and described in detail herein, their scope should not be limited thereby rather their scope should be determined by that of the appended claims. | A seamless, woven, flexible fluid containment vessel or vessels for transporting and containing a large volume of fluid, particularly fresh water, having beam stabilizers, beam separators, reinforcing, and the method of making the same. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to a device for supporting outside plant direct buried cable, as opposed to other devices which are specifically for use in overhead installations, such as U.S. Pat. No. 5,042,767. Outside plant direct buried cable can be described as power transmission cable, telecommunication cable television cable, and fiber optic cable.
2. Description of the Prior Art
Cable supports are used by outside plant utility companies to support cable while splicing or repairing. The problem with currently used supports is that when they are placed or assembled for use, they can be dangerous and unsafe. Cable supports are generally used in pits dug by back-hoes to expose underground facilities for customer service or repair projects. If cable supports are made out of metallic conductive material, the user will be subject to possible electrical shock from power induced through the metallic material. If the pit has water on the bottom, then electrocution from existing direct buried power is very probable.
There are cable supports that have to be driven into the ground, to achieve stability, in order to support the direct buried cable being spliced or repaired. This is extremely hazardous to not only the user, but to others nearby. Pounding a metallic support through a direct buried power line or a large gas line is certain danger. Nonconductive supports that have to be driven into the ground are no less dangerous. They can damage other direct buried facilities as they are being driven into the ground below work level. These damages are left undetected until service is later restored and a technician has to be subjected to it during trouble shooting to isolate that damage. A nonconductive cable support can crack or penetrate gas lines that while being driven can push rocks or stones together causing sparks enough to ignite the gas. This invention eliminates those hazards.
SUMMARY OF THE INVENTION
This invention relates to a device to support the various types of direct buried cables safely and correctly when being installed or repaired. It comprises a means for supporting a cable in a below ground level environment where underground facilities are placed, such that a safe rigid mount is established on an adjustable self standing support that will maintain the integrity of both the technicians safety and the adjacent facilities.
It is an object of the invention to provide a device to support a direct buried cable and protect the user from being harmed by adjacent facilities and weather conditions. A device of this means would not have to be driven into the ground because it has self standing capabilities thus eliminating any danger from coming in contact with direct buried power transmission lines and or gas mains. A device of this means would not be conductive, therefore, eliminating the possibility of being harmed through power surges due to power leakage or electrical storms.
Another object of this invention is to be adjustable in such a way that the vertical and horizontal embodiments may provide flexibility in positioning, therefore, able to conform to its surroundings and allowing space enough for technicians to perform job functions safely.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view showing the embodiment of the "Self-Supporting Non-Conductive Cable Stand" device in its entirety.
FIG. 2 is an exploded view, showing the embodiments in a pre-assembled state.
FIG. 3 is view showing the left and right sides of the invention in FIG. 1.
FIG. 4 is a side elevation view showing the cable support bracket of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Prior art support devices that resemble the present invention shown in FIG. 1 are made of, either all or in part, metallic material around the base that can conduct electrical surges to a technician from damaged power utilities or from water surrounding the base at the bottom of a pit 15. Still, other support devices resembling posts 3 have been used to support utilities like cable 12 in an area or space provided as that shown in FIG. 1. Prior art devices resembling post 3 are pointed at one end to penetrate the soil and then driven down through the dirt by a sledge hammer, or the like, to achieve stability, therefore, increasing the chance of damaging other utilities and or causing serious bodily harm.
To prevent these serious problems from happening, a cable 12 must be supported by a self-standing device in order to offer isolation from other utilities and their elements. These drawings illustrate that by making the base including base portions 1 & 2 and the posts 3 out of non-conductive material, an insulation factor will be provided for protection, thus, creating a safer working environment.
The drawing in FIG. 1 is illustrating a condition of a work environment as is set up on location 15. Base portions 1 & 2 are made of round non-conductive material such as plastic or fiberglass to act as an insulator. These parts are sectional in that they separate from each other into two portions. Base portions 1 & 2 are each generally U-shaped in form and include a middle seciton and two end sections, these three sections together forming the U-shape. The assembly of the base portions 1 & 2 form a rectangular shape for stability and adjustment. Base portion 1 differs from base portion 2 in that base portion 1 provides a smaller diameter section on both of its end sections for the end sections of base portion 2 to slide onto. Each smaller diameter section, in its cylindrical shape, allows the end sections of base portion 2 to slide back and forth until a desired position is achieved. These two base portion, when assembled, are designed to be placed on a flat or semi-flat surface in pits, level areas above ground and manholes to provide a stable foundation for the remaining pieces and also for the cable to be spliced.
Referring to the drawing in FIG. 1, posts 3 are two vertical pieces of round material attached to the middle sections of base portions 1 & 2. These vertical posts are also made of a non-conductive material like plastic or fiberglass for the purpose of insulation. When post 3 is connected to base portions 1 & 2, these vertical posts become a section of the stand that provides the desired height in which the cable will be placed by providing holes to position bracket 4.
Referring to the drawing in FIG. 1, bracket 4 is another component of the stand which is unique in its design. Two brackets are provided with are multi-functional in that (1), they provide the main support means for the cable, (2), they are interchangeable, since they can be fastened to either the right or left port 3, (3) they can be turned upside down to allow for different techniques and applications for splicing and still offer the cable a surface or slot to be set upon, and (4) they provide clamping portion 16 each having a square opening for bar 9 to be inserted into and to rest in which will allow the complete unit to slide back and forth for adjustments.
Referring to the drawing in FIG. 1, sliding bar 9 is another component of the stand that provides strength and a means for splicing tools to be fastened to. This bar is a piece of metal that can be used from any various types of stock available. It rests inside of the square openings provided by bracket 4 so that the rest of the assembly can be moved in and out for positioning. After positioning is finished, bolts 8 are then tightened so that the posts component as part 3 will become rigid holding bar 9 stationary. Sliding bar 9 can be made of steel or metal because it becomes isolated from any source that may cause harm, in that, it is fastened to bracket 4 which is attached to upright post 3 that is made of non-conductive material.
Referring to the drawing in FIG. 1, a metallic bolt 10 is a fastening means that can be from any various type of stock. These bolts are used to hold base portions 1 & 2 from sliding back and forth after the sections have been positioned for use. Base portions 1 & 2 have position holes through which bolts 10 are placed.
Referring to the drawing in FIG. 2, keeper pins 11 of any of the various types are used for keeping bolts 10 from pulling out of their placement.
Referring to the drawing in FIG. 2, threaded bolt 5 or screw means of many various types is used as a tightening means extending from a rear side of the bracket 4 to keep slide bar 9 vertically stationary after positioning.
Referring to the drawing in FIG. 2 a wing nut 7 or a similar device of the many various types is used as a means of tightening bracket 4 to post 3 after positioning bracket 4 to a desired height.
Referring to the drawing in FIG. 3, this drawing illustrates the parts that are made out of non-conductive material or fiberglass. This drawing also shows how the stand is designed generally into two separate sections.
Referring to the drawing in FIG. 4, the bracket 4 includes a cradle 14 which is constructed of two U-shaped members forming two half cylindrical surfaces, respectively, wherein the U-shaped members are juxtaposed and facing in opposite directions for the cable to rest in during set up and splicing. The cable can be tied down around this area to restrict cable movement to assure a correct cable opening.
Bracket 4 is designed to be used either right side up or upside down, depending on the technique and tools applied for splicing, thus, the purpose for the half cylindrical surfaces provide the same result in either position as long as they are facing up. When the bracket 4 is turned in either direction, the clamping portion 16 with the square opening at the one end of the bracket 4 performs its function identically. Clamping portion 16 is directly centered below or above the cradle 14 so that its counterpart, which is the smaller square sliding bar 9 that slides into and through this larger square opening, can be tightened after positioning and a surface for tools to be fastened directly above or below the splice opening. This bracket 4 has a bolt 5, washer 6 and nut 7 incorporated in the center on the backside to become fastened to or removed from the posts 3 and allows these left and right brackets 4 to become interchangeable.
Referring to the drawing in FIG. 2, this drawing illustrates the separate embodiments that compose the "Self-Supporting Non-Conductive Cable Stand Device" and how they are to be assembled and in what direction they move. Base portion 1 slides into base portion 2, then the two bolts 10 are placed through the positioning holes of base portions 1 & 2 and locked with pin 11, after a desired width is achieved. The keeper pins 11 are placed into the bolts 10 to keep base portions 1 & 2 from pulling apart. The vertical posts 3 are placed into the middle sections of base portions 1 & 2.
The weight of the cable placed onto bracket 4 will keep these vertical posts 3 secure. The slide bar 9 is placed into the square openings of the clamping portions of the brackets 4. The brackets, or cable heads, 4 are then placed up against through the positioning holes of the vertical posts 3 at a desired height such that the bolt 5 is inserted through a respective opening in the post 3, and washer 6 and nut 7 are tightened on bolt 5 so that bracket 4 will not pull out of post 3. Slide bar 9 can be tightened by bolt, or screw, 8 to keep slide bar 9 from moving. This completes the assembly process of the stand and can now be used as a device for splicing cable and provides technicians with a safer alternative for supporting cable by eliminating the use of other means that would have to be hammered into the ground which could cause serious injury and damage. | A stand, comprised of adjustable parts provides a structure for utility cables to be set upon so they can be spliced or repaired. The stand is designed to be placed on flat or semi-flat surfaces without additional support. Constructed primarily from non-conductive material, such as plastic or fiberglass, the stand is lightweight and provides excellent protection from electrocution and gas explosions that may occur from adjacent utilities if disturbed. The stand does not have to be driven into the ground to gain support. It features horizontal and vertical adjustments that conform to cable levels at trench or manhole depths and also to size availability of potholes or pits making it a very productive tool in most situations. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a vehicle including a door, and in particular to cars including doors.
[0002] Car passenger doors are currently provided with a latch situated midway up the rear side of the door. When the door is closed, the latch engages with a striker positioned on the door post (such as an A post, a B post or a C post) such that the door is fixed in a closed position. The latch can be released from the striker by operation of an inside door handle or an outside door handle.
[0003] Moreover cars are known which have a specifically designed front and rear crumpled zones to absorb a substantial amount of an impact to the car body. A passenger, which term is to be understood as including a driver, in the car is protected from the accident by a rigid safety cell formed by the passenger compartment. The strength of the safety cell is very much dependant on the doors remaining in their closed position when an impact occurs, either to the side or to either end of the car.
[0004] During road traffic accidents the doors of vehicles have been known to open or at least partially open thereby reducing the strength of the safety cell and endangering the safety of the passengers.
SUMMARY OF THE INVENTION
[0005] An object of the present invention is to provide a passenger door which is less likely to open or partially open during an impact.
[0006] Thus according to the present invention there is provided a vehicle including a passenger door for substantially closing a door aperture of the vehicle, the vehicle including a self engaging latch assembly comprising a latch mounted on one of the door or door aperture and a striker mounted on the other of the door or door aperture for latching the door in a closed position, the vehicle further including a plurality of fixings bolts positioned around the periphery of one of the door or door aperture to engage respective abutments positioned around the periphery of the other of the door or door aperture to further secure the door in a closed position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:
[0008] [0008]FIG. 1 is a partial schematic side view of a vehicle according to the present invention incorporating a passenger door according to the present invention.
[0009] [0009]FIG. 2 is a view of a latch assembly of FIG. 1 taken in the direction of arrow A.
[0010] [0010]FIG. 3 is a view of bolt arrangement of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] With reference to the figures there is shown a vehicle 10 having a door aperture 12 which is substantially closed by a door 14 . Door aperture 12 is defined by fixed structure of the vehicle, in this case an A post, a door sill, a B post, a roof edge and a windscreen pillar. Door 14 is pivotally mounted at a front portion by hinges 16 to the vehicle 10 the door includes a substantially vertical opening edge 18 (in this case a rear edge) a substantially horizontal lower edge 20 , a hinged edge 22 (in this case a front hinged edge), a substantially horizontal upper edge 24 , and an angled edge 26 , the angle of which is substantially determined by the angle of a windscreen (not shown) of the vehicle.
[0012] The door further includes a window aperture 28 being bounded at a lower edge by a body portion 15 of door 14 and at a front upper and rear portion by a front window rim 30 , and upper window rim 32 , and a rear window rim 34 respectively. The door includes a self engaging latch 36 having a rotating claw of conventional type engagable with a door mounted striker also of known type to secure the door in a closed position.
[0013] Inside handle 38 and outside handle 40 are manually actuatable to open the latch 36 .
[0014] In this case outside handle 40 operates via rod 41 to rotate the release lever 42 of latch 36 in an anticlockwise direction as shown in FIG. 2. Furthermore inside handle 38 acts via rod 44 and crank lever 46 (which is pivotable about axis B) to also rotate the release lever 42 in an anticlockwise direction when viewing FIG. 2.
[0015] The door further includes a plurality of bolt assemblies 50 , 51 , 52 , 53 , 54 and 55 each positioned around the periphery of the door. The bolt assemblies 50 , 51 , 52 , 53 , 54 and 55 are connected to the release lever 42 by bowden cables 56 , 57 , 58 , 59 , 60 and 61 .
[0016] With reference to FIG. 3 there is shown bolt assembly 51 and bowden cables 56 and 57 . Bolt assembly 51 comprises a housing 62 mounted on the door 14 and having a recess 64 in which is mounted spring 66 and bolt 68 . Bolt 68 includes a stem portion 70 being bent at 90 degrees and having an end 78 for engagement with bowden cables 56 and 57 . Stem 70 is slidable within housing 62 .
[0017] Attached to end 70 B of stem 70 is an engagement portion 72 having engagement face 74 and a camming surface 76 .
[0018] The door aperture 12 includes a striker 78 having an engagement surface 80 and a camming surface 82 .
[0019] With the door in the position as shown in FIG. 3 operation of the inside or outside door handle causes the release lever 42 to rotate in an anticlockwise direction when viewing FIG. 2 thus pulling on bowden cable 58 . Bowden cable 58 is connected to bowden cable 57 at the bolt assembly 52 . Thus bowden cable 57 is caused to move in the direction of arrow C of FIG. 3, causing the bolt 68 to also move in the direction of arrow C of FIG. 3. Such action disengages the engagement faces 74 and 80 thus allowing the door to open.
[0020] Release of the inside or outside door handle allows the bolt to return to the position as shown as FIG. 3 (albeit with the door in an open position).
[0021] When the door is closed the camming surfaces 82 and 76 cause the bolt 68 to move in the direction of arrow C until such time as engagement portion 72 moves past engagement surface 80 whereupon spring 66 biases the bolt 68 in the direction of arrow D of FIG. 3 causing the engagement surfaces 74 and 80 and re-engage.
[0022] All bolt assemblies are substantially similar.
[0023] It will be appreciated that bolt assemblies 50 and 55 are only connected to a single bowden cable since they are at the terminus of a series of bowden cables.
[0024] It will be appreciated that bolt assemblies 50 , 51 , 52 , 53 , 54 and 55 are all self engaging bolt assemblies. In further embodiments it is possible to have bolts which do not self engage but which can for example engage upon actuation of locking of the door.
[0025] It will also be appreciated that in further embodiment bowden cables 56 , 57 and 58 can be replaced by a single bowden cable with appropriate connections being made to this cable by the bolts. Similarly bowden cables 59 , 60 and 61 can be replaced by a single bowden cable.
[0026] It will apparent that whilst the bolts have been described has being mounted on the door and engaging strikers mounted on an associated door aperture, it is also possible to mount the self engaging latch and bolts on the door aperture and provide appropriate strikers for the self engaging latch and bolts on the door, with each striker being adjacent its corresponding latch/bolt when the door is in a closed position.
[0027] The foregoing description is only exemplary of the principles of the invention. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, so that one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specially described. For that reason the following claims should be studied to determine the true scope and content of this invention. | A passenger door having a self engaging latch for latching the door in a closed position, the door further including a plurality of fixing bolts positioned about the periphery of the door to further secure the door in a closed position. | 4 |
TECHNICAL FIELD
The present disclosure relates to semiconductor memory devices, and more particularly, to a semiconductor memory device configured to share a local I/O (input/output) line.
BACKGROUND
A conventional memory core structure minimizes distance between memory cell arrays to maximize memory cell efficiency. In particular, the conventional memory core structure requires a maximum of 16 bits of data outputs, and thus shares a local I/O line.
On the other hand, a high speed memory such as a double data rate (DDR), a DDR-II and a graphic memory outputs a maximum of 32 bits of data. The high speed memory is required to have high speed burst operation, and thus the core must read data as many as a number of the bursts in advance. This function is a prefetch function. The DDR uses 2 bit prefetch and the DDR-II uses 4 bit prefetch. For example, the X16 DDR-II operates at 400MHz with 4 bursts, uses 4 bit prefetch, and reads 64 bits of data by one core access.
However, because the conventional core structure gradually increases an operation speed and widens a bandwidth, it cannot share the local I/O line. As a result, a spatial efficiency cannot be achieved.
SUMMARY OF THE DISCLOSURE
A semiconductor memory device configured to share a local I/O line by sequentially outputting data in a pipeline form is disclosed herein.
The semiconductor memory device includes: a memory cell array including a plurality of memory cells; a plurality of bit line sense amplifiers configured to sense and to amplify data stored in the plurality of memory cells; a plurality of bit lines configured to transmit the data stored in the plurality of memory cells to the plurality of bit line sense amplifiers, respectively; a plurality of bit line dividing circuits configured to selectively divide the plurality of bit lines; and a plurality of column selecting circuits configured to sequentially transmit the data amplified by the plurality of bit line sense amplifiers to corresponding I/O lines.
BRIEF DESCRIPTION OF THE DRAWINGS
The disclosure will be described in terms of several embodiments to illustrate its broad teachings. Reference is also made to the attached drawings.
FIG. 1 is a block diagram illustrating a semiconductor memory device using a pipeline fetch structure; and
FIGS. 2 a and 2 b are timing diagrams of operation signals to explain the operation of the semiconductor memory device of FIG. 1 .
DETAILED DESCRIPTION
The present disclosure will be described in detail with reference to the accompanying drawings.
FIG. 1 is a block diagram illustrating a semiconductor memory device 100 using a pipeline fetch structure. In the semiconductor memory device 100 , a bit line dividing unit 20 is formed at the center portion of a memory cell array 10 composed of a plurality of memory cells 11 , 12 , 13 and 14 . Sense amplifier arrays 30 and 40 composed of a plurality of sense amplifiers with two shown as 31 and 41 , respectively, are connected to both ends of the memory cell array 10 . Here, the bit line dividing unit 20 including NMOS transistors NM 1 , NM 2 , NM 3 and NM 4 that perform switching operation, according to an up bit line switching signal UBL and a down bit line switching signal DBL for dividing bit lines.
In the operation of reading data from memory cells 11 and 12 connected to an enabled word line WLO, the up bit line switching signal UBL is at a low level to turn off the NMOS transistors NM 1 and NM 2 when the data stored in the memory cell 11 connected to the upper sense amplifier array 30 are read. Accordingly, a length of the bit line pair BL and /BL is decreased and a bit line capacitance is reduced, and thereby improving sensing efficiency of the sense amplifiers.
On the other hand, when the data stored in the memory cell 12 connected to the lower sense amplifier array 40 are read, the down bit line switching signal DBL is at a high level to turn on the NMOS transistors NM 3 and NM 4 . The bit line pair BL and /BL of the memory cell 12 positioned in the upper memory cell array 30 of the bit line dividing unit 20 is connected to the lower sense amplifier array 40 . Accordingly, the reading speed of the data stored in the memory cell 11 connected to the upper sense amplifier array 30 is higher than that of the data stored in the memory cell 12 connected to the lower sense amplifier array 40 to sequentially perform the operations for reading the data stored in the two memory cells 11 and 12 . As a result, local I/O line LIO can be shared by using the aforementioned operation property. To illustrate this concept, column selecting units 50 and 60 sequentially transmit the data amplified by the sense amplifiers 31 and 41 to the local I/O line LIO by using a column select signal YI, an up column select signal UYI and a down column select signal DYI.
To read the data from memory cells 11 and 12 , the data stored in the memory cell 11 connected to the upper sense amplifier array 30 are transmitted to a bit line BL 0 . Here, the up bit line switching signal UBL becomes a low level to turn off the NMOS transistors NM 1 and NM 2 .
The data on the bit line BL 0 are sensed and amplified by the bit line sense amplifier 31 . Here, the column select signal YI becomes a high level to turn on NMOS transistors NM 5 and NM 6 . Accordingly, the data amplified by the bit line sense amplifier 31 are transmitted to the local I/O line LIO through a data bus DB. Here, the up column select signal UYI becomes a high level to turn on NMOS transistors NM 9 and NM 10 to form a path for outputting the data amplified by the bit line sense amplifier 31 to the data bus DB.
Thereafter, the data stored in the memory cell 12 connected to the lower sense amplifier array 40 are transmitted to a bit line BL 1 . The down bit line switching signal DBL becomes a high level to turn on the NMOS transistors NM 3 and NM 4 . The data on the bit line BL 1 are sensed and amplified by the bit line sense amplifier 41 . Here, the column select signal YI becomes a high level to turn on NMOS transistors NM 7 and NM 8 .
Therefore, the data are transmitted to the local I/O line LIO through the data bus DB. The down column select signal DYI becomes a high level to turn on NMOS transistors NM 11 and NM 12 to form a path for outputting the data amplified by the bit line sense amplifier 41 to the data bus DB.
Further, the data stored in the memory cell 14 connected to the lower sense amplifier array 40 are transmitted to the bit line BL 1 to read the data from the memory cells 13 and 14 connected to an enabled word line WL 1 . The down bit line switching signal DBL becomes a low level to turn off the NMOS transistors NM 3 and NM 4 .
The data on the bit line BL 1 are sensed and amplified by the bit line sense amplifier 41 . Here, the column select signal YI becomes a high level to turn on the NMOS transistors NM 7 and NM 8 . Accordingly, the data amplified by the bit line sense amplifier 41 are transmitted to the local I/O line LIO through the data bus DB. The down column select signal DYI becomes a high level to turn on the NMOS transistors NM 11 and NM 12 to form a path for outputting the data amplified by the bit line sense amplifier 41 to the data bus DB.
Thereafter, the data stored in the memory cell 13 connected to the upper sense amplifier array 30 are transmitted to the bit line BL 0 . Here, the up bit line switching signal UBL becomes a high level to turn on the NMOS transistors NM 1 and NM 2 . The data on the bit line BL 0 are sensed and amplified by the bit line sense amplifier 31 . The column select signal YI becomes a high level to turn on the NMOS transistors NM 5 and NM 6 .
Therefore, the data are transmitted to the local I/O line LIO through the data bus DB. The up column select signal UYI becomes a high level to turn on the NMOS transistors NM 9 and NM 10 to form a path for outputting the data amplified by the bit line sense amplifier 31 to the data bus DB.
FIGS. 2 a and 2 b are timing diagrams of operation signals to explain the operation of the semiconductor memory device of FIG. 1 . Here, the column select signal YI is inputted with a frequency twice as fast as the general column select signal, and a wave pipe delay time T has a time less than 10 nanoseconds.
FIG. 2 a is a timing diagram of the read operation of the data stored in the memory cells 11 and 12 connected to the enabled world line WL 0 . The data stored in the memory cell 11 connected to the upper sense amplifier array 30 are transmitters the sense amplifier 31 through the bit line pair BL 0 and /BL 0 , and the sense amplifier 31 senses and amplifies the data. The column select signal YI has a high level in a period when the up column select signal UYI is becomes a high level to transmit the data amplified by the sense amplifier 31 to the data bus DB.
Thereafter, the data stored in the memory cell 12 connected to the lower sense amplifier array 40 are transmitted to the sense amplifier 41 through the bit line pair BL 1 and /BL 1 , and the sense amplifier 41 senses and amplifies the data. The column select signal YI has a high level in a period when the down column select signal DYI becomes a high level to transmit the data amplified by the sense amplifier 41 to the data bus DB.
FIG. 2 b is a timing diagram of the read operation of the data stored in the memory cells 13 and 14 connected to the enabled world line WL 1 . The data stored in the memory cell 14 connected to the lower sense amplifier array 40 are transmitted to the sense amplifier 41 through the bit line pair BL 1 and /BL 1 , and the sense amplifier 41 senses and amplifies the data. The column select signal YI has a high level in a period when the down column select signal DYI becomes a high level to transmit the data amplified by the sense amplifier 41 to the data bus DB.
Thereafter, the data stored in the memory cell 13 connected to the upper sense amplifier array 30 are transmitted to the sense amplifier 31 through the bit line pair BL 0 and /BL 0 , and the sense amplifier 31 senses and amplifies the data. The column select signal YI has a high level in a period when the up column select signal UYI becomes a high level to transmit the data amplified by the sense amplifier 31 to the data bus DB.
As mentioned above, efficiency of the core structure is improved with the I/O bandwidth in the high speed memory device by using the pipeline fetch function. Moreover, the semiconductor memory device disclosed herein reduces the bit line capacitance and improves the sensing speed of the sense amplifiers by using the switch element for dividing the bit lines. Thus, the semiconductor memory device sequentially senses the data stored in the memory cells connected to the same word line with the sense amplifiers to share the local I/O line.
Many changes and modifications to the embodiments described herein could be made. The scope of some changes is discussed above. The scope of others will become apparent from the appended claims. | A semiconductor memory device configured to share a local I/O line is described herein. The device includes: a memory cell array including a plurality of memory cells; a plurality of bit line sense amplifiers configured to sense and to amplify data stored in the plurality of memory cells; a plurality of bit lines configured to transmit transmitting the data stored in the plurality of memory cells to the plurality of bit line sense amplifiers, respectively; a plurality of bit line dividing circuits configured to selectively divide the plurality of bit lines; and a plurality of column selecting circuits configured to sequentially transmit the data amplified by the plurality of bit line sense amplifiers to corresponding I/O lines. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a heat transfer recording apparatus having an ink donor film which is free from any skew.
A heat transfer recording apparatus records information in such a way that the hot-melt ink applied to one surface of the base for an ink donor film is melted in accordance with pictorial information, and transferred onto recording paper. The melting of the solid ink is carried out in such a way that a thermal head (thermal recording head) is brought into contact with the ink donor film moving in the scanning direction, and heat is transmitted to the solid ink through the film base. The ink donor film is required to be as thin as several tens of microns in order to ensure transmission of heat, and proper resolution.
If the film is so thin, however, the ink donor film is very likely to skew when it is subjected to any tension caused by error in the positioning of various parts of the film transport. Any such skew produces a wave on the ink donor film in a direction which is perpendicular to that of its travel, and a wrinkle is formed thereon in the area between the thermal head and the back roll. The wrinkle on the ink donor film disables recording of information by heat transfer. Accordingly, it has heretofore been necessary in a heat transfer recording apparatus to ensure a high degree of accuracy in the fabrication and positioning of parts in the transportation system for the ink donor film and the supply roll for the ink donor film. This has hindered reduction in the cost of the apparatus.
SUMMARY OF THE INVENTION
In view of these circumstances, it is an object of this invention to provide a heat transfer recording apparatus including a skew preventing mechanism which can prevent or reduce the skew of an ink donor film.
According to this invention, the aforesaid object may be attained by a stress absorbing roll unit provided between the supply roll and the area of contact between the thermal head and the back roll, and adapted for inclination at an angle which is variable in accordance with the stress developed along the edges of the ink donor film.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in detail with reference to the accompanying drawings, in which:
FIG. 1 is a view showing in side elevation the essential arrangement of the heat transfer recording apparatus according to this invention; and
FIG. 2 is a front elevational view showing the stress absorbing roll installed on the frame.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the essential arrangement of the heat transfer recording apparatus embodying this invention. This apparatus essentially comprises a supply roll 2 of an ink donor film 1, a thermal head 3, a back roll 5 pressing recording paper 4 against the thermal head 3 with the ink donor film 1 therebetween, a stress absorbing roll unit 6 positioned between the supply roll 2 and the back roll 5, a drive roll 7 contacting the back roll 5, and separating the recording paper 4 from the ink donor film 1, a take-up roll 8 recovering the ink donor film 1 from the back roll 5 and the drive roll 7, and a pair of feed rolls 10 which feed the recording paper 4 into a recording station 9 defined between the thermal head 3 and the back roll 5. Except for the stress absorbing roller, the apparatus of FIG. 1 is substantially similar to that described in copending application Ser. No. 312,020, filed Oct. 16, 1981, and corresponding to Japanese Application No. 55-144419, filed in Japan on Oct. 17, 1980.
If the recording operation is started by depression of a start button (not shown), the feed rolls 10 are driven to move the recording paper 4 in the direction of an arrow A. When the leading end of the paper 4 has reached the vicinity of the stress absorbing roll unit 6, the transport system for the ink donor film is driven to deliver the film 1 from the supply roll 2 to the recording station 9. The paper 4 is then sandwiched between the ink donor film 1 and the back roll 5, and fed into the recording station 9 where the recording of information on paper by heat transfer takes place. The paper 4 leaves the recording station 9 with the ink donor film 1, but when it passes through the area of contact between the back roll 5 and the drive roll 7, it is separated from the ink donor film 1, and travels in the direction of an arrow B. The paper is then discharged into a paper tray (not shown) through a paper outlet (not shown).
The supply roll 2 has an outer periphery shown by broken line at 2A at the very beginning of operation, and has a gradually decreasing diameter as the ink donor film 1 is delivered to the recording station. The supply roll 2 comprises a roll of ink donor film 1 wound about a paper tube. Since there may occur some unevenness in the manner in which the film is wound about the paper tube, or an error in the positioning of the paper tube relative to the apparatus, it is practically impossible to maintain the surface of the ink donor film 1 in parallel to the axis of the back roll 5. Whenever the ink donor film 1 ceases to be in parallel to the axis of the back roll 5, it imparts a force to either end of the stress absorbing roll unit 6, so that the ends of the roll unit 6 are raised or lowered in a direction which is perpendicular to the surface of the film 1.
FIG. 2 illustrates the principle of the stress absorbing roll unit 6. The unit 6 utilizes the principle of a balancing toy. It comprises a roll 6A, a shaft 6B on which the roll 6A is rotatably supported, a member 6C for supporting the shaft 6B, and pin 11 which supports the supporting member 6C rotatably on a projection 12 of the frame of the apparatus. If the ink donor film 1 is subjected to any stress when it is travelling, the supporting member 6C is tilted about the pin 11 in the direction in which the stress has been applied. As a result, the unit 6 immediately absorbs the stress acting on the ink donor film 1, and prevents formation of any wave on the film surface. The pin 11 may advantageously be connected to the roll unit somewhat loosely, so that the roll 6A may also be displaced to some extent in the direction of travel of the ink donor film 1 for appropriate removal of any stress acting on the film in the direction of its travel.
According to this invention, it is, thus, possible to provide a highly reliable heat transfer recording apparatus which permits recording of information by heat transfer without any problem, even with normal errors in the installation of the ink donor film transport system.
Although the invention as hereinabove described comprises only the stress absorbing roll between the supply roll and the back roll, it is, of course, possible to also position other rolls, such as guide or feed rolls, in that area. | A stress absorbing roller is disposed in the travel path of the ink donor film in a heat transfer recording device. The roller is pivotable to compensate for alignment errors in the transport system, to thereby eliminate wrinkles in the donor film at the recording station. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is based on Japanese priority application No. 2001-205188 filed on Jul. 5, 2001, the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to semiconductor integrated circuit devices and methods of producing the same, and more particularly to a semiconductor integrated circuit device including a nonvolatile semiconductor storage device and using a plurality of supply voltages, and a method of producing such a semiconductor integrated circuit device.
A flash memory device is a nonvolatile semiconductor storage device that stores information in the form of electric charges in floating gate electrodes. The flash memory device, which has a simple device configuration, is suitable for forming a large-scale integrated circuit device.
In the flash memory device, information is written or erased by injecting hot carriers into and extracting hot carriers by the Fowler-Nordheim-type tunnel effect from the floating gate electrodes through a tunnel insulating film. Since a high voltage is required to generate such hot carriers, the flash memory device has a voltage rise control circuit that raises a supply voltage provided in its peripheral circuits cooperating with memory cells. Therefore, transistors used in such peripheral circuits have to operate at a high voltage.
On the other hand, it has been practiced of late to form such a flash memory device and a high-speed logic circuit on a common semiconductor substrate as a semiconductor integrated circuit device. In such a high-speed logic circuit, a transistor employed therein is required to operate at a low voltage. Therefore, such a semiconductor integrated circuit device is required to use a plurality of supply voltages.
2. Description of the Related Art
FIGS. 1A through 1Q are diagrams showing a production process of the conventional semiconductor integrated circuit device including such a flash memory and using a plurality of supply voltages.
In FIG. 1A , a flash memory cell region A, a low-voltage operation transistor region B, and a high-voltage operation transistor region C are formed in partitions on a silicon (Si) substrate 11 on which a field oxide film or an isolation structure (not shown in the drawing) such as a shallow trench isolation (STI) structure is formed. In the step of FIG. 1A , a tunnel oxide film 12 A of a thickness of 8 to 10 nm is formed on the above-described regions A through C by performing thermal oxidation on the surface of the Si substrate 11 at temperatures ranging from 800 to 1100° C. In the step of FIG. 1B , an amorphous silicon film 13 doped with phosphorous (P) and having a thickness of 80 to 120 nm and an insulating film 14 having a so-called oxide-nitride-oxide (ONO) structure are successively deposited on the tunnel oxide film 12 A. The ONO insulating film 14 is formed of a silicon dioxide (SiO 2 ) film 14 c of a thickness of 5 to 10 nm deposited by chemical vapor deposition (CVD) on the amorphous silicon film 13 , a silicon nitride (SiN) film 14 b of a thickness of 5 to 10 nm deposited by CVD on the SiO 2 film 14 c, and a thermal oxide film 14 a of a thickness of 3 to 10 nm formed on the surface of the SiN film 14 b. The ONO insulating film 14 has a good leakage-current characteristic.
Next, in the step of FIG. 1C , a resist pattern 15 A is formed on the flash memory cell region A, and the ONO insulating film 14 , the amorphous silicon film 13 , and the tunnel oxide film 12 A are removed from the low-voltage operation transistor region B and the high-voltage operation transistor region C on the Si substrate 11 by using the resist pattern 15 A as a mask so that the surface of the Si substrate 11 is exposed in the regions B and C. In removing the tunnel oxide film 12 A, wet etching using hydrofluoric acid (HF) is performed so that the surface of the Si substrate 11 is exposed to the HF in the regions B and C.
In the step of FIG. 1D , the resist pattern 15 A is removed, and a thermal oxide film 12 C of a thickness of 10 to 50 nm is formed in the regions B and C to cover the Si substrate 11 by performing thermal oxidation at temperatures ranging from 800 to 1100° C. The thermal oxide film 12 C may be replaced by a thermal nitride oxide film.
In the step of FIG. 1E , another resist pattern 15 B is formed in the flash memory cell region A to cover the ONO insulating film 14 and in the high-voltage operation transistor region C to cover the thermal oxide film 12 C, and the thermal oxide film 12 C is removed from the low-voltage operation transistor region B by HF processing by using the resist pattern 15 B as a mask so that the surface of the Si substrate 11 is exposed in the region B. By the step of FIG. 1E , the surface of the Si substrate 11 is subjected to the second HF processing in the region B.
In the step of FIG. 1F , the resist pattern 15 B is removed, and a thermal oxide film 12 B of a thickness of 3 to 10 nm is formed on the exposed Si substrate 11 in the region B by performing thermal oxidation at temperatures ranging from 800 to 1100° C. The thermal oxide film 12 B may be replaced by a thermal nitride oxide film. Further, in the step of FIG. 1F , as a result of the thermal oxidation for forming the thermal oxide film 12 B, the thickness of the thermal oxide film 12 C formed in the high-voltage operation transistor region C increases.
Next, in the step of FIG. 1G , an amorphous silicon film 16 doped with P and having a thickness of 100 to 250 nm is deposited on the structure of FIG. 1F by plasma CVD. The amorphous silicon film 16 may be replaced by a polysilicon film. Further, the amorphous silicon film 16 may be doped with P in a later step. In the step of FIG. 1H , a resist pattern 17 A is formed on the amorphous silicon film 16 , and by using the resist pattern 17 A as a mask, patterning is performed successively on the amorphous silicon film 16 , the ONO insulating film 14 , and the amorphous silicon film 13 in the flash memory cell region A so that a multilayer gate electrode structure 16 F of the flash memory which structure is formed of an amorphous silicon pattern 13 A, an ONO pattern 14 A, and an amorphous silicon pattern 16 A and includes the amorphous silicon pattern 13 A as a floating gate electrode is formed in the region A. In the step of FIG. 1G , it is possible to form a silicide film of, for instance, tungsten silicide (WSi) or cobalt silicide (CoSi) on the amorphous silicon film 16 as required. Further, it is also possible to form a non-doped polysilicon film and then form an n-type gate electrode of P or arsenic (As) or a p-type gate electrode of boron (B) or difluoroboron (BF 2 ) in a later step of ion implantation.
Next, in the step of FIG. 1I , the resist pattern 17 A is removed, and a new resist pattern 17 B is formed to cover the flash memory cell region A. By using the resist pattern 17 B as a mask, patterning is performed on the amorphous silicon film 16 in the low-voltage operation transistor region B and the high-voltage operation transistor region C so that a gate electrode 16 B of a low-voltage operation transistor and a gate electrode 16 C of a high-voltage operation transistor are formed in the regions B and C, respectively.
Next, in the step of FIG. 1J , the resist pattern 17 B is removed, and a protection oxide film (also referred to as a protection insulating film or a thermal oxide film) 18 is formed, by performing thermal oxidation at temperatures ranging from 800 to 900° C., to cover each of the multilayer gate electrode structure 16 F in the flash memory cell region A, the gate electrode 16 B in the low-voltage operation transistor region B, and the gate electrode 16 C in the high-voltage operation transistor region C.
Next, in the step of FIG. 1K , a resist pattern 19 A is formed on the structure of FIG. 1J so as to cover the low-voltage operation transistor region B, the high-voltage operation transistor region C, and a part of the flash memory cell region A. By using the resist pattern 19 A and the multilayer gate electrode structure 16 F as masks, ion implantation of P + is performed typically with a dose of 1×10 14 to 3×10 14 cm −2 at accelerating voltages ranging from 30 to 80 keV so that an n-type diffusion region 11 a is formed next to the multilayer gate electrode structure 16 F in the Si substrate 11 . P + may be replaced by As + .
In the step of FIG. 1K , by using the resist pattern 19 A as a mask, ion implantation of As + is performed typically with a dose of 1×10 15 to 6×10 15 cm −2 at accelerating voltages ranging from 30 to 50 keV so that another n-type diffusion region 11 b is formed inside the n-type diffusion region 11 a. In the step of FIG. 1K , no ion implantation is performed in the low-voltage operation transistor region B and the high-voltage operation transistor region C since the regions B and C are covered with the resist pattern 19 A.
Next, in the step of FIG. 1L , the resist pattern 19 A is removed, and a new resist pattern 19 B is formed to cover the regions B and C and leave the region A exposed. Further, in the step of FIG. 1L , by using the resist pattern 19 B as a mask, ion implantation of As + is performed with a dose of 5×10 14 to 5×10 15 cm −2 at accelerating voltages ranging from 30 to 50 keV. As + may be replaced by P + . As a result, an impurity concentration is increased in the n-type diffusion region 11 b and at the same time, a yet another n-type diffusion region 11 c is formed in the flash memory cell region A by using the multilayer gate electrode structure 16 F as a self-alignment mask. At this point, the step of FIG. 1K may be deleted.
Next, in the step of FIG. 1M , the resist pattern 19 B is removed, and a resist pattern 19 C is formed on the Si substrate 11 so as to leave only the low-voltage operation transistor region B exposed. Further, in the step of FIG. 1M , ion implantation of a p-type or n-type impurity is performed by using the resist pattern 19 C as a mask so that a pair of lightly doped drain (LDD) diffusion regions 11 d are formed on both sides of the gate electrode 16 B in the Si substrate 11 in the region B with the gate electrode 16 B serving as a self-alignment mask.
Next, in the step of FIG. 1N , the resist pattern 19 C is removed, and a resist pattern 19 D is formed on the Si substrate 11 so as to leave only the high-voltage operation transistor region C exposed. Further, in the step of FIG. 1N , ion implantation of a p-type or n-type impurity element is performed by using the resist pattern 19 D as a mask so that a pair of LDD diffusion regions 11 e are formed on both sides of the gate electrode 16 C in the Si substrate 11 in the region C. The diffusion regions 11 d and 11 e may be formed in the same step.
Further, in the step of FIG. 10 , sidewall insulating films 16 s are formed on both sides of each of the multilayer gate electrode structure 16 F, the gate electrode 16 B, and the gate electrode 16 C by depositing and performing etchback on a CVD oxide film. In the step of FIG. 1P , a resist pattern 19 E is formed to cover the flash memory cell region A and leave the low-voltage operation transistor region B and the high-voltage operation transistor region C exposed. Further, by performing ion implantation of a p-type or n-type impurity element with the resist pattern 19 E and the gate electrodes B and C serving as a mask, p-type or n-type diffusion regions 11 f are formed on both sides of the gate electrode 16 B in the Si substrate 11 in the region B, and similarly, p-type or n-type diffusion regions 11 g are formed on both sides of the gate electrode 16 C in the Si substrate 11 in the region C. A low-resistance silicide film of, for instance, WSi or CoSi may be formed as required on the surface of each of the diffusion regions 11 f and 11 g by silicide processing.
In the step of FIG. 1Q , an interlayer insulating film 20 is formed on the Si substrate 11 so as to continuously cover the regions A through C. Further, in the region A, contact holes are formed in the interlayer insulating film 20 so that the diffusion regions 11 b and 11 c are exposed, and W plugs 20 A are formed in the contact holes. Likewise, in the region B, contact holes are formed in the interlayer insulating film 20 so that the diffusion regions 11 f are exposed, and W plugs 20 B are formed in the contact holes. In the region C, contact holes are formed in the interlayer insulating film 20 so that the diffusion regions 11 g are exposed, and W plugs 20 C are formed in the contact holes.
In the production process of the semiconductor integrated circuit device including the flash memory device having the multilayer gate electrode structure 16 F, in the step of FIG. 1J , the protection oxide film 18 of a thickness of 5 to 10 nm is formed on the sidewall faces of the multilayer gate electrode structure 16 F by thermal oxidation performed at temperatures ranging from 800 to 900° C. As a result of the thermal oxidation, the protection oxide film 18 is formed not only on the multilayer gate electrode structure 16 F but also on the sidewall faces of each of the gate electrode 16 B formed in the low-voltage operation transistor region B and the gate electrode 16 C formed in the high-voltage operation transistor region C as shown in FIGS. 2A and 2B .
At this point, the protection oxide film 18 forms bird's beaks that penetrate under the gate electrode 16 B in the region B as shown circled by broken lines in FIG. 2B . Therefore, especially in a low-voltage operation transistor whose gate length is short, that is, whose gate oxide film 12 B is thin, a substantial change in the thickness of the gate oxide film 12 B is effected right under the gate electrode 16 B, thus causing a problem that a threshold characteristic shifts from a desired value.
Indeed, such a problem is prevented from occurring if the protection oxide film 18 is not formed. However, without formation of the protection oxide film 18 , electrons retained in the amorphous silicon pattern 13 A (hereinafter, also referred to as a floating gate electrode pattern 13 A) are dissipated to the sidewall insulating films 16 s formed by CVD and etchback in the step of FIG. 10 as shown in FIG. 3B so that information stored in the flash memory device is lost in a short period of time. On the other hand, with the protection oxide film 18 that is a high-quality thermal oxide film hardly allowing a leakage current being formed on the sidewalls of the floating gate electrode pattern 13 A, the electrons injected into the floating gate electrode pattern 13 A are stably retained therein as shown in FIG. 3A .
Therefore, it is essential to form the protection oxide film 18 in the semiconductor integrated circuit device including the flash memory device. However, formation of such a protection oxide film inevitably causes the problem of a change in the threshold characteristic of a MOS transistor forming a peripheral or logic circuit. Such a problem of a change in the threshold characteristic of the MOS transistor is noticeable when the MOS transistor is a high-speed transistor having a short gate length.
FIG. 4 is a plan view of a configuration of a flash memory cell (flash memory device) having a single-layer gate electrode structure by related art. In FIG. 4 , the same element as those of the previous drawings are referred to by the same numerals, and a description thereof will be omitted.
According to FIG. 4 , a device region 11 A is formed on the Si substrate 11 by a field oxide film 11 F. One end of the above-described floating gate electrode pattern 13 A is formed on the Si substrate 11 to cross the device region 11 A. In the device region 11 A, by using the floating gate electrode pattern 13 A as a self-alignment mask, the n − -type source region 11 a and the n + -type source line region 11 b are formed on one side, and the n + -type drain region 11 c is formed on the other side.
On the Si substrate 11 , another device region 11 B is formed next to the device region 11 A. An n + -type diffusion region 11 C is formed in the device region 11 B. The other end of the floating gate electrode pattern 13 A is formed as a coupling part 13 Ac covering the diffusion region 11 C.
FIG. 5A is a sectional view of the flash memory cell of FIG. 4 taken along the line X-X′.
According to FIG. 5A , the tunnel oxide film 12 A is formed between the source line region 11 b and the drain region 11 c on the Si substrate 11 , and the floating gate electrode pattern 13 A is formed on the tunnel oxide film 12 A. Further, the n − -type source region 11 a is formed outside the n + -type source line region 11 b in the Si substrate 11 . The sidewall insulating films 16 s are formed on the sidewalls of the floating gate electrode pattern 13 A.
FIG. 5B is a sectional view of the flash memory cell of FIG. 4 taken along the line Y-Y′.
According to FIG. 5B , the floating gate electrode pattern 13 A continuously extends from the device region 11 A to the adjacent device region 11 B on the field oxide film 11 F formed on the Si substrate 11 . The coupling part 13 Ac of the floating gate electrode pattern 13 A is capacitive-coupled via an oxide film 12 Ac to the high-density diffusion region 11 C.
At the time of a write (program) operation, by providing the source line region 11 b, applying a drain voltage of +5 V to the drain region 11 c, and applying a write voltage of +10 V to the high-density diffusion region 11 C as shown in FIGS. 6A and 6B , the potential of the floating gate electrode pattern 13 A rises so that hot electrons are injected into the floating gate electrode pattern 13 A via the tunnel oxide film 12 A in the device region 11 A.
On the other hand, at the time of an erase operation, an erase voltage of +15 V is applied to the source line region 11 b with the drain region 11 c and the high-density diffusion region 11 C being grounded as shown in FIGS. 6C and 6D . As a result, the electrons in the floating gate electrode pattern 13 A tunnel through the tunnel oxide film 12 A to the source region 11 a to be absorbed into a source power supply through the source line region 11 b.
Thus, in the flash memory cell of FIG. 4 , the high-density diffusion region 11 C serves as a control gate electrode, and unlike the conventional flash memory cell of a multilayer gate structure, it is unnecessary to form the above-described ONO insulating film 14 between the polysilicon floating gate electrode and the polysilicon control gate electrode. In the flash memory cell of FIGS. 5A and 5B , the oxide film 12 Ac serves as the ONO insulating film 14 . Since the oxide film 12 Ac is formed on the Si substrate 11 by thermal oxidation, the oxide film 12 Ac has high quality.
FIGS. 7A through 7M are diagrams showing a production process of a semiconductor integrated circuit device including the flash memory cell of FIG. 4 in addition to the low-voltage operation transistor B and the high-voltage operation transistor C. In the drawings, the same elements as those previously described are referred to by the same numerals, and a description thereof will be omitted.
According to FIG. 7A , the thermal oxide film 12 C of a thickness of 5 to 50 nm is formed on the Si substrate 11 by performing thermal oxidation at temperatures ranging from 800 to 1100° C. in each of the flash memory cell region A, the low-voltage operation transistor region B, and the high-voltage operation transistor region C. In the step of FIG. 15B , the thermal oxide film 12 C is removed from the flash memory cell region A by a patterning process using a resist pattern 15 1 .
Next, in the step of FIG. 7C , the resist pattern 15 1 is removed, and the tunnel oxide film 12 A of a thickness of 5 to 15 nm is formed on the surface of the Si substrate 11 in the region A by performing thermal oxidation at temperatures ranging from 800 to 1100° C. In the step of FIG. 7C , as a result of the thermal oxidation for forming the tunnel oxide film 12 A, the thermal oxide film 12 C is developed in each of the regions B and C.
Next, in the step of FIG. 7D , the thermal oxide film 12 C is removed from the low-voltage operation transistor region B by a patterning process using a resist pattern 15 2 . Then, in the step of FIG. 7E , after the resist pattern 15 2 is removed, the thermal oxide film 12 B of a thickness of 3 to 10 nm is formed on the exposed Si substrate 11 in the region B by performing thermal oxidation at temperatures ranging from 800 to 1100° C. In the step of FIG. 7E , as a result of the thermal oxidation for forming the thermal oxide film 12 B, the tunnel oxide film 12 A is developed in the region A and the thermal oxide film 12 C is developed in the region C.
Next, in the step of FIG. 7F , the amorphous silicon film 13 uniformly doped with P and having a thickness of 150 to 200 nm is formed on the Si substrate 11 . In the step of FIG. 7G , patterning is performed on the amorphous silicon film 13 with a resist pattern 17 1 serving as a mask, so that the floating gate electrode pattern 13 A is formed in the flash memory cell region A, a gate electrode pattern 13 B is formed in the low-voltage operation transistor region B, and a gate electrode pattern 13 C is formed in the high-voltage operation transistor region C.
Next, in the step of FIG. 7H , the surfaces of the floating gate electrode pattern 13 A and the gate electrode patterns 13 B and 13 C are covered with the protection oxide film 18 of a thickness of 5 to 10 nm by thermal oxidation at temperatures ranging from 800 to 900° C. Then, in the step of FIG. 7I , with a resist pattern 17 2 serving as a mask, the source region 11 a is formed by performing ion implantation of P + or As + with a dose of 1×10 14 to 5×10 14 cm −2 at accelerating voltages ranging from 30 to 80 keV.
Further, in the step of FIG. 7J , with the regions B and C being covered with a resist pattern 17 3 , ion implantation of As + is performed with a dose of 5×10 14 to 3×10 15 cm −2 at accelerating voltages ranging from 30 to 50 keV in the region A by using the floating gate electrode pattern 13 A as a self-alignment mask. Thereby, the n + -type source line region 11 b is formed inside the source region 11 a and the n + -type drain region 11 c is formed on the opposite side of a channel region from the source region 11 a.
Next, in the step of FIG. 7K , a resist pattern 17 3 covering the flash memory cell region A is formed, and the LDD regions 11 d and 11 e are formed in the regions B and C, respectively, by ion implantation of a p-type or n-type impurity element.
Further, in the step of FIG. 7L , the sidewall oxide films 16 s are formed on both sidewalls of each of the floating gate electrode pattern 13 A and the gate electrode patterns 13 B and 13 C. In the step of FIG. 7M , with the flash memory region A being covered with a resist pattern 17 4 , the diffusion regions 11 f and 11 g are formed in the regions B and C, respectively, by ion implantation of a p-type or n-type impurity element.
Also in the production of the semiconductor integrated circuit device including the flash memory device of such a single-layer gate structure, when the thermal oxide film 18 is formed as a protection insulating film to cover the single-layer gate electrode structure (the floating gate electrode pattern) 13 A in the flash memory cell region A as shown in detail in FIG. 8A in the step of FIG. 7H , the same thermal oxide film 18 is also formed in the low-voltage transistor region B so as to cover the gate electrode 13 B as shown in FIG. 8B . As a result, bird's beaks that penetrate right under the gate electrode 13 B are formed as shown circled in FIG. 8B . Therefore, the low-voltage operation transistor formed in the region B is prevented from having a desired threshold characteristic.
SUMMARY OF THE INVENTION
It is a general object of the present invention to provide a semiconductor integrated circuit device and a method of producing the same in which the above-described disadvantage is eliminated.
A more specific object of the present invention is to provide a semiconductor integrated circuit device in which formation of bird's beak right under the gate electrode of a semiconductor device formed together with a flash memory device on a substrate is effectively prevented.
Yet another object of the present invention is to provide a method of producing such a semiconductor integrated circuit device.
The above objects of the present invention are achieved by a semiconductor integrated circuit device including a substrate, a nonvolatile memory device formed in a memory cell region of the substrate and having a multilayer gate electrode structure including a tunnel insulating film covering the substrate and a floating gate electrode formed on the tunnel insulating film and having sidewall surfaces covered with a protection insulating film formed of a thermal oxide film, and a semiconductor device formed in a device region of the substrate, the semiconductor device including a gate insulating film covering the substrate and a gate electrode formed on the gate insulating film, wherein a bird's beak structure is formed of a thermal oxide film at an interface of the tunnel insulating film and the floating gate electrode, the bird's beak structure penetrating into the floating gate electrode along the interface from the sidewall faces of the floating gate electrode, and the gate insulating film is interposed between the substrate and the gate electrode to have a substantially uniform thickness.
The above objects of the present invention are also achieved by a semiconductor integrated circuit device including: a substrate; a nonvolatile memory device formed in a memory cell region of the substrate, the nonvolatile memory device including a first active region covered with a tunnel insulating film, a second active region formed next to the first active region and covered with an insulating film, a control gate formed of an embedded diffusion region formed in the second active region, a first gate electrode extending on the tunnel insulating film in the first active region and forming a bridge between the first and second active regions to be capacitive-coupled via the insulating film to the embedded diffusion region in the second active region, the first gate electrode having sidewall faces thereof covered with a protection insulating film formed of a thermal oxide film, and a diffusion region formed on each of sides of the first gate electrode in the first active region; and a semiconductor device formed in a device region of the substrate, the semiconductor device including a gate insulating film covering the substrate and a second gate electrode formed on the gate insulating film, wherein a bird's beak structure is formed of a thermal oxide film at an interface of the tunnel insulating film and the first gate electrode, the bird's beak structure penetrating into the first gate electrode along the interface from the sidewall faces of the first gate electrode, and the gate insulating film is interposed between the substrate and the second gate electrode to have a substantially uniform thickness.
According to the above-described semiconductor integrated circuit devices, no bird's beak structure is formed to penetrate into the second gate electrode. Therefore, the problem of a change in the threshold characteristic of the semiconductor device can be avoided.
The above objects of the present invention are also achieved by a method of producing a semiconductor integrated circuit device, including the steps of (a) forming a semiconductor structure including a tunnel insulating film covering a memory cell region of a substrate, a first silicon film covering the tunnel insulating film, an insulating film covering the first silicon film, and a gate insulating film covering a logic device region of the substrate, (b) depositing a second silicon film on the semiconductor structure formed in the step (a) so that the second silicon film covers the insulating film in the memory cell region and the gate insulating film in the logic device region, (c) forming a multilayer gate electrode structure in the memory cell region by successively patterning the second silicon film to serve as a control gate electrode, the insulating film, and the first silicon film in the memory cell region with the second silicon film being left in the logic device region, (d) forming a protection oxide film so that the protection oxide film covers the multilayer gate electrode structure in the memory cell region and the second silicon film in the logic device region, (e) forming diffusion regions in both sides of the multilayer gate electrode structure in the memory cell region by performing ion implantation of an impurity element into the substrate with the multilayer gate electrode structure and the second silicon film being employed as masks, (f) forming a gate electrode in the logic device region by patterning the second silicon film, and (g) forming diffusion regions in the logic device region by performing ion implantation with the gate electrode being employed as a mask, whereby a nonvolatile memory device is formed in the memory cell region and a semiconductor device is formed in the logic device region.
The above objects of the present invention are further achieved by a method of producing a semiconductor integrated circuit device, including the steps of (a) forming a semiconductor structure including a tunnel insulating film covering a memory cell region of a substrate and a gate insulating film covering a logic device region of the substrate, (b) depositing a silicon film on the semiconductor structure formed in the step (a) so that the silicon film covers the tunnel insulating film in the memory cell region and the gate insulating film in the logic device region, (c) forming a first gate electrode in the memory cell region by selectively patterning the silicon film with the silicon film being left in the logic device region, (d) forming a protection oxide film so that the protection oxide film covers the first gate electrode in the memory cell region and the silicon film in the logic device region, (e) forming diffusion regions on both sides of the first gate electrode in the memory cell region by performing ion implantation of an impurity element into the substrate with the first gate electrode and the silicon film being employed as masks, (f) forming a second gate electrode in the logic device region by patterning the silicon film, and (g) forming diffusion regions in the logic device region by performing ion implantation with the second gate electrode being employed as a mask, whereby a nonvolatile memory device is formed in the memory cell region and a semiconductor device is formed in the logic device region.
According to the above-described methods, the protection oxide film is formed to cover the multilayer gate electrode structure or the gate electrode in the memory cell region before the gate electrode is patterned in the logic device region. The protection oxide film prevents the bird' beak structure from being formed as a penetration into the gate electrode in the logic device region. Therefore, the problem of a change in the threshold characteristic of the semiconductor device in the device region can be avoided. Further, when the diffusion regions are formed in the memory cell region by ion implantation, the device region is covered with the silicon film. By using the silicon film as a mask, a resist process may be omitted, thus simplifying the production process of the semiconductor integrated circuit device.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings, in which:
FIGS. 1A through 1Q are diagrams showing a production process of a conventional semiconductor integrated circuit device including a flash memory device of a multilayer gate structure;
FIGS. 2A and 2B are diagrams for illustrating a disadvantage of the conventional semiconductor integrated circuit device including the flash memory device of the multilayer gate structure;
FIGS. 3A and 3B are diagrams for illustrating a role of a protection oxide film employed in the flash memory device of the multilayer gate structure employed in the conventional semiconductor integrated circuit device;
FIG. 4 is a plan view of a flash memory cell of a single-layer gate structure according to related art;
FIGS. 5A and 5B are sectional views of the flash memory cell of FIG. 4 ;
FIGS. 6A through 6D are diagrams for illustrating write and erase operations of the flash memory cell of FIG. 4 ;
FIGS. 7A through 7M are diagrams showing a production process of a semiconductor integrated circuit device including the flash memory cell of FIG. 4
FIGS. 8A and 8B are diagrams for illustrating a disadvantage of the semiconductor integrated circuit device including the flash memory cell of FIG. 4 ;
FIGS. 9A through 9I are diagrams showing a production process of a semiconductor integrated circuit device according to a first embodiment of the present invention;
FIGS. 10A and 10B are diagrams for illustrating an effect of the first embodiment;
FIGS. 11A and 11B are diagrams for illustrating another effect of the first embodiment;
FIGS. 12A through 12I are diagrams showing a production process of a semiconductor integrated circuit device according to a second embodiment of the present invention; and
FIGS. 13A and 13B are diagrams for illustrating effects of the second embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A description will now be given, with reference to the accompanying drawings, of embodiments of the present invention.
First Embodiment
FIGS. 9A through 9I are diagrams showing a production process of a semiconductor integrated circuit device according to a first embodiment of the present invention. In the drawings, the same elements as those previously described are referred to by the same numerals, and a description thereof will be omitted.
In this embodiment, the steps of FIGS. 1A through 1G are first performed, so that a structure corresponding to FIG. 1G is obtained in the step of FIG. 9A . At this point, a silicon-on-insulator (SOI) substrate may replace the Si substrate 11 . Further, a tunnel nitride film may replace the tunnel oxide film 12 A.
Further, in the step of FIG. 9B , the multilayer gate electrode structure 16 F is formed in the flash memory cell region A by performing patterning using the resist pattern 17 A described in the step of FIG. 1H . In the step of FIG. 9B , no patterning is performed on the low-voltage operation transistor region B and the high-voltage operation transistor region C that are covered with the resist pattern 17 A.
In this embodiment, next, in the step of FIG. 9C , the resist pattern 17 A is removed, and the protection insulating film 18 is formed of a thermal oxide film to cover the multilayer gate electrode structure 16 F by performing thermal oxidation at temperatures ranging from 800 to 900° C. The same thermal oxide film 18 is also formed on the surface of the amorphous silicon film 16 in each of the regions B and C.
Further, in the step of FIG. 9C , with the multilayer gate electrode structure 16 F serving as a self-alignment mask, the diffusion region 11 c is formed in the flash memory cell region A by performing ion implantation of As + (or P + ) under the same conditions as in the above-described step of FIG. 1L . The impurity concentration may be the same on the side of the diffusion regions 11 a and 11 b and the side of the diffusion region 11 c. At this point, no ion is injected into the Si substrate 11 in the regions B and C that are covered with the amorphous silicon film 16 . A resist pattern that has an opening on the flash memory cell region A may be employed.
In the step of FIG. 9D , by using the resist pattern 17 B previously described in the step of FIG. 1I as a mask, patterning is performed on the amorphous silicon film 16 in the regions B and C so that the gate electrodes 16 B and 16 C are formed in the low-voltage operation transistor region B and the high-voltage operation transistor region C, respectively.
Next, in the step of FIG. 9E , with the resist pattern 19 C previously described in the step of FIG. 1M being employed as a mask, the LDD diffusion regions 11 d are formed in the Si substrate 11 in the region B by performing ion implantation of an n-type or p-type impurity element therein.
In the step of FIG. 9F , with the resist pattern 19 D previously described in the step of FIG. 1N being employed as a mask, the LDD diffusion regions 11 e are formed in the Si substrate 11 in the region C by performing ion implantation of an n-type or p-type impurity element therein. In the steps of FIGS. 9E and 9F , the diffusion regions 11 d and 11 e may be formed under the same ion implantation conditions in the same step.
In the step of FIG. 9G , which corresponds to the above-described step of FIG. 10 , the sidewall insulating films 16 s are formed on each of the multilayer gate electrode structure 16 F and the gate electrodes 16 B and 16 C. In the step of FIG. 9H , which corresponds to the above-described step of FIG. 1P , the flash memory cell region A is covered with the resist pattern 19 E. Further, with the gate electrodes 16 B and 16 C and the sidewall insulating films 16 s being used as self-alignment masks, the diffusion regions 11 f and 11 g are formed in the Si substrate 11 in the regions B and C, respectively, by performing ion implantation of an n-type or p-type impurity element therein.
Further, by performing the same step as previously described in FIG. 1Q , a semiconductor integrated circuit device of the structure of FIG. 9I corresponding to FIG. 1Q can be obtained.
In this embodiment, when the protection insulating film 18 is formed by thermal oxidation in the step of FIG. 9C , no patterning has been performed on the amorphous silicon film 16 in the regions B and C. As a result, in the regions B and C, the thermal oxide film 18 is formed on the surface of the amorphous silicon film 16 , but is prevented from being formed at an interface between the amorphous silicon film 16 and the gate oxide film 12 B. Further, no such thermal oxidation is performed in any step after the patterning step of the gate electrodes 16 B and 16 C of FIG. 9D . Therefore, although the protection insulating film 18 is formed to cover the multilayer gate electrode structure 16 F as shown in FIG. 10A , no thermal oxide film other than the gate oxide film 12 B is developed on the bottom of the gate electrode 16 B. Therefore, the problem of a change in the threshold characteristic of the low-voltage operation transistor can be avoided.
As shown circled in FIG. 10A , in the step of FIG. 9C , bird's beaks are formed under the floating gate electrode pattern 13 A with the formation of the protection insulating film 18 . On the other hand, with respect to the MOS transistors of the regions B and C, bird's beaks, if ever formed, are far smaller in thickness and penetration distance than those formed under the floating gate electrode pattern 13 A.
Further in this embodiment, as shown in FIGS. 11A and 11B , in the ion implantation step of FIG. 9C , no resist pattern is required to be provided in the low-voltage operation transistor region B and the high-voltage operation transistor region C since the regions B and C are covered with the amorphous silicon film 16 . Consequently, this simplifies the production process of the semiconductor integrated circuit device.
Second Embodiment
FIGS. 12A through 12I are diagrams showing a production method of a semiconductor integrated circuit device including a flash memory device of a single-layer gate electrode structure according to a second embodiment of the present invention. In the drawings, the same elements as those previously described are referred to by the same numerals, and a description thereof will be omitted.
In this embodiment, steps corresponding to those of FIGS. 7A through 7D are first performed, so that a structure corresponding to that of FIG. 7E is obtained in the step of FIG. 12A . In this embodiment, an SOI substrate may also replace the Si substrate 11 . Further, a thermal nitride oxide film may replace the tunnel oxide film 12 A or the thermal oxide films 12 B and 12 C.
Next, in the step of FIG. 12B , which corresponds to the step of FIG. 7F , the amorphous silicon film 13 of a thickness of 100 to 300 nm is deposited on the structure of FIG. 12A . The amorphous silicon film 13 may be replaced by a polysilicon film. Further, the amorphous silicon film 13 may be doped with P + . In the step of FIG. 12C , patterning is performed on the amorphous silicon film 13 by using a resist pattern 27 1 as a mask so that the floating gate electrode pattern 13 A is formed. The resist pattern 27 1 covers the low-voltage operation transistor region B and the high-voltage operation transistor region C. Consequently, no patterning is performed on the amorphous silicon film 13 in the regions B and C in the step of FIG. 12C .
Next, in the step of FIG. 12D , the resist pattern 27 1 is removed, and the protection insulating film 18 of a thickness of 5 to 10 nm is formed of a thermal oxide film so as to cover the floating gate electrode pattern 13 A in the region A by performing thermal oxidation at temperatures ranging from 800 to 900° C. As a result of the thermal oxidation, the thermal oxide film 18 is also formed on the surface of the amorphous silicon film 13 in the regions B and C.
Next, in the step of FIG. 12E , a resist pattern 27 2 corresponding to the resist pattern 17 2 in FIG. 7I is formed on the structure of FIG. 12D . With the resist pattern 27 2 being employed as a mask, ion implantation of P + (or As + ) is performed with a dose of 1×10 14 to 5×10 14 cm −2 at accelerating voltages ranging from 30 to 80 keV so that the diffusion region 11 a is formed next to the floating gate electrode pattern 13 A in the flash memory cell region A. Further in the step of FIG. 12E , after the ion implantation of P + , ion implantation of As + is performed with a dose of 1×10 15 to 6×10 15 cm −2 at accelerating voltages ranging from 30 to 80 keV so that the resistance of the diffusion region 11 a is reduced.
Next, in the step of FIG. 12F , the resist pattern 27 2 is removed, and with the floating gate electrode pattern 13 A being employed as a mask, ion implantation of As + is performed with a dose of 5×10 14 to 3×10 15 cm −2 at accelerating voltages ranging from 20 to 60 keV in the region A so that the diffusion regions 11 b and 11 c are formed in the Si substrate 11 in the region A. At this point, the step of FIG. 12E is omittable. Further, a resist pattern having an opening only on the flash memory cell region A may be formed alternatively.
Next, in the step of FIG. 12G , a resist pattern 27 3 is formed on the structure of FIG. 12F . The flash memory cell region A is covered with the resist pattern 27 3 . Then, patterning is performed on the amorphous silicon film 13 with the resist pattern 27 3 being employed as a mask in the regions B and C so that the gate electrodes 13 B and 13 C are formed therein.
In the step of FIG. 12H , the resist pattern 27 3 is removed and a resist pattern 27 4 covering the flash memory cell region A is formed. With the resist pattern 27 4 being employed as a mask, an n-type or p-type impurity element is introduced into the Si substrate 11 by ion implantation so that the LDD diffusion regions 11 d and 11 e are formed in the regions B and C, respectively.
Further, in the step of FIG. 12I , the resist pattern 27 4 is removed, and a CVD oxide film 16 S is deposited. Further, with the CVD oxide film 16 S being protected by a resist pattern 27 5 in the flash memory cell region A, etchback is performed in the regions B and C so that the sidewall oxide films 16 s are formed on the sidewalls of each of the gate electrodes 13 B and 13 C.
Furthermore, by performing the same ion implantation as in the step of FIG. 7M on the structure of FIG. 12I , the diffusion regions 11 f and 11 g in the Si substrate 11 . A p-type or n-type gate electrode is also formable. A low-resistance silicide film of, for instance, WSi or CoSi may be formed as required on the surface of each of the gate electrodes 13 B and 13 C and the diffusion regions 11 f and 11 g by silicide processing.
FIGS. 13A and 13B are diagrams showing detailed configurations of the flash memory device and the low-voltage operation transistor formed according to this embodiment.
As shown in FIG. 13A , the floating gate electrode pattern 13 A has not only its sidewall faces but also its top surface uniformly covered with the protection insulating film 18 in this embodiment. Therefore, electrons accumulated in the floating gate electrode pattern 13 A are stably retained even if the flash memory device is left in a hot environment for a long time.
Further in this embodiment, the amorphous silicon film 13 is not patterned in the regions B and C when the thermal oxidation step of FIG. 12D is performed. Therefore, as shown in FIGS. 13B , no bird' beaks of the thermal oxide film penetrate under the gate electrodes 13 B and 13 C. This stabilizes the threshold characteristic and the operation characteristic of each MOS transistor formed on the Si substrate 11 on which the flash memory device is formed as well. The improvements in the threshold characteristic and the operation characteristic are remarkable in a low-voltage operation transistor having a short gate length and a thin gate oxide film.
In this embodiment, no resist pattern is required to be formed in the ion implantation step of FIG. 12F , thus simplifying the production process.
In the flash memory device of a multilayer-gate type according to the previous embodiment, the multilayer gate electrode structure 16 F may also have its sidewall faces and top surface covered continuously with the protection insulating film 18 in the configuration of FIG. 9I as in that of FIG. 12I .
According to the present invention, a protection oxide film is formed to cover a multilayer gate electrode structure or a floating gate electrode pattern in a flash memory cell region before a gate electrode is patterned in a first or second device region. The protection oxide film prevents a bird' beak structure from being formed to penetrate into the gate electrode in the device region. Therefore, the problem of a change in the threshold characteristic of a semiconductor device in the device region can be avoided. Further, according to the present invention, when diffusion regions are formed in the flash memory cell region by ion implantation, the device region is covered with an amorphous silicon film. By using the amorphous silicon film as a mask, a resist process may be omitted, thus simplifying the production process.
The present invention is not limited to the specifically disclosed embodiments, but variations and modifications may be made without departing from the scope of the present invention. | A semiconductor integrated circuit device includes a substrate, a nonvolatile memory device formed in a memory cell region of the substrate, and a semiconductor device formed in a device region of the substrate. The nonvolatile memory device has a multilayer gate electrode structure including a tunnel insulating film and a floating gate electrode formed thereon. The floating gate electrode has sidewall surfaces covered with a protection insulating film. The semiconductor device has a gate insulating film and a gate electrode formed thereon. A bird's beak structure is formed of a thermal oxide film at an interface of the tunnel insulating film and the floating gate electrode, the bird's beak structure penetrating into the floating gate electrode along the interface from the sidewall faces of the floating gate electrode, and the gate insulating film is interposed between the substrate and the gate electrode to have a substantially uniform thickness. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a snowblower and more specifically relates to controls for ensuring safe operation of a snowblower.
Snowblowers include separate drives through which power is respectively transmitted from an internal combustion engine to a pair of traction wheels and to a collector-impeller. Safety standards require that a snowblower operator be in the operator's position behind the snowblower when the collector-impeller is operating and also require that the snowblower be equipped with a "deadman" control which disengages the traction drive when the operator leaves the operator's station. Such a deadman's control is known in the art.
SUMMARY OF THE INVENTION
According to the present invention there is provided a control for ensuring safe operation of a snowblower.
It is a broad object of the invention to provide a control for a snowblower which will effect snowblower operation that complies with the aforementioned safety standards.
A more specific object is to provide electrical circuitry including two switches having respective first contacts respectively formed in part by a traction drive control lever and by a collector-impeller drive control lever, the two levers respectively bearing such relationship to respective second contacts that a safety circuit containing the two switches and connected to an engine ignition systen is placed in a condition stopping the engine when the traction drive control lever is moved to an extreme drive-disengage position while the collector-impeller is in a drive-disengage position, but is maintained in a condition keeping the engine running when the traction drive control lever is moved to an intermediate drive-disengage position while the collector-impeller is in a drive disengage position.
These and other objects will become apparent from a reading of the ensuing description together with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a right front perspective view of a snowblower of the type with which the present invention is particularly adapted for use.
FIG. 2 is a left side elevational view, partially in section, showing the relationship between the collector-impeller drive control lever and a first switch contact, the lever being shown in solid lines in a drive-disengage position and in dashed lines in a drive-engage position.
FIG. 3 is a right side elevational view of the traction drive control lever showing its relationship to a second switch contact, the lever being shown in solid lines in an extreme drive disengage position, in broken lines in an intermediate drive-disengage position and in dashed lines in a drive-engage position.
FIG. 4 is a sectional view taken along line 4--4 of FIG. 3 and showing the relationship between the lever and the switch contact when the lever is in its extreme drive-disengage position.
FIG. 5 is a view similar to that of FIG. 4 but showing the relationship between the lever and switch contact when the lever is in either its intermediate drive-disengage or in its drive-engage positions.
FIG. 6 is a schematic showing of the ignition system and the safety interlock electrical circuitry of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, therein is shown a walk-behind snowblower indicated in its entirety by the reference numeral 10. The snowblower 10 includes a main frame or chassis 12 supported on a pair of traction or drive wheels 14. An internal combustion engine 16 is mounted on the frame 12 between the wheels 14 and includes a forwardly projecting output shaft 18. Secured on the forward side of the frame 12 is a collector-impeller assembly including a cylindrical impeller housing 20 having an open front collector housing 22 secured to and forming an integral continuation of the front end thereof. The impeller housing 20 is provided with a tangentially extending discharge tube 24 and mounted for receiving snow blown through the tube is a discharge spout or chute 26.
Extending axially in the impeller housing 20 is a fore-and-aft impeller shaft 28 having its forward end drivingly coupled to a transverse collector shaft 30 by means gearing, not shown, located in a housing 32. An impeller 34 is mounted on the shaft 28 and includes a plurality of blades for propelling snow through the tube 24 while a spirally arranged collecting blade 36 is mounted on the shaft 30 for augering snow into contact with the impeller 34.
Mounted on the output shaft 18 of the engine 16 are a traction drive pulley 38 and a collector-impeller drive pulley 40. A first drive train (not shown) is connected between the pulley 38 and an axle having the wheels 14 mounted on opposite ends thereof while a second drive train (not shown) is connected between the pulley 40 and the impeller shaft 30. The first and second drive train may be of any conventional construction capable of being easily engaged and disengaged and for an example of such drive trains reference may be had to U.S. Pat. No. 3,580,351 issued to Mollen on May 25, 1971.
The snowblower heretofore described is controlled manually by means of a plurality of controls. Specifically, a pair of handlebars 42 have respective forward ends fixed to the frame 12 and have respective hand grips 44 at rear ends thereof. Fixed on the left handlebar 42 just forwardly of the grip 44 is a mounting bracket 46 (FIG. 3) having a portion 48 extending about the handlebar and fixed thereto by a fastener 50. The bracket 46 includes a vertical portion 52 extending downwardly from the portion 48 and pivotally secured to the portion 52, as by a horizontal pivot pin 54, is one leg of an L-shaped traction drive control lever 56 having a second leg 57 arranged to be gripped concurrently with the handgrip 44. Connected to the lever 56 and extending to a controlled element (not shown) of the traction drive is a control rod 58. In a conventional manner (not shown) the lever 56 is arranged as a deadman control in which the controlled element and hence the control rod 58 and lever 56 are biased to an extreme drive-disengage position, as shown in dashed lines in FIG. 3, wherein the lever 56 is rotated to an extreme clockwise location disposing the leg 57 away from the grip 44. The lever 56 may be manually moved counterclockwise from its extreme drive-disengage position, first to an intermediate drive-disengage position shown in broken lines in FIG. 3 and then to a drive-engage position wherein the leg 57 is disposed so as to be concurrently grasped by an operator's hand with the grip 44. Mounted on the support bracket portion 52 in a location so as to be engaged by the lever 56 only when the latter is in or is between its intermediate drive-disengaging and drive-engaging positions is a switch contact 60 having a purpose to be described hereinbelow. The contact 60 is mounted on the portion 52 by means of a pair of mounts 62, each including a pair of rubber grommets 63 sandwiching the contact and providing electrical insulation between the contact 60 and the bracket 46.
Extending between and connected to the handlbar 42 at a location forwardly of the lever 56 is a control console 64 having left, intermediate and right fore-and-aft extending guide slots 66, 68 and 70 respectively located therein and respectively receiving upwardly projecting throttle control, speed-direction control and collector-impeller drive control levers 72, 74 and 76. A flexible push-pull element 78 is connected between the lever 72 and a carburetor control arm in a conventional manner (not shown) and respective control rods 80 and 82 are respectively connected at one of their ends to the levers 74 and 76 and at their opposite ends to speed-direction and collector-impeller drive control elements (not shown). Of these three levers, only the collector-impeller drive control lever 76 is involved in the present invention and for the sake of brevity only the details of the mounting of the lever 76 is shown in detail.
Thus, as can best be seen in FIG. 2, the console 64 includes a bracket 84 having a fore-and-aft extending support rod 86 fixed therein. The lower end of the lever 76 is bifurcated and has opposite legs straddling the rod 86 and connected thereto by means of a pivot pin 88. A right leg of the bifurcated lower end of the lever 76 includes an angled extension 90 in which the upper end of the control rod 82 is pivotally mounted. The lever 76 is swingable fore-and-aft about the pin 88 between a forward drive-engage position and a rearward drive-disengage position, these positions being respectively shown in dashed and solid lines in FIG. 2. Mounted on the rod 86 in a location so as to be engaged by the lever 76 only when the latter is in its drive-disengage position is a switch contact 92, having a purpose to be described hereinbelow. The contact 92 is held is place by a mount 94 including a pair of rubber grommets 96 sandwiching the contact 92 and serving to electrically insulate the latter from the rod 86.
Referring now to FIG. 6, therein is shown magneto ignition system indicated in its entirety by the reference numeral 98. The system 98 includes a fly wheel magnet 100, which rotates past a magneto coil 102 having a primary winding 104 having one side connected to a condenser-breaker point assembly 106 and having its other side connected to ground. A secondary winding 108 is positioned such that when the breaker points of the assembly 106 open the change in current in the winding 104 will induce a high voltage spike in the winding 108, the high voltage spike effecting firing of a spark plug 110 connected to one end of the winding 108. The other end of the secondary winding 108 is connected to ground. Coupled to the ignition system 98 between the primary winding 104 and the condenser-breaker point assembly 106 is a safety module or circuit 112. Specifically, the circuit 112 includes a lead 114 coupled to the system, 98 at junction 116 and coupled to a pair of switches 118 and 120 connected in parallel with each other and in series with a diode 122 and a relay coil 124 of a relay 126. A capacitor 128 is connected in parallel with the coil 124 and the circuit is completed to ground via a ground lead 130. The relay 126 includes a plunger 132 having a contact 134 at its left end which is normally biased, as by a spring 136, into engagement with a pair of contacts 138 to complete a circuit through a ground lead 140 connected to the lead 114 between the junction 116 and the switches 118 and 120 and connected to a grounded diode 142. At this point, it is notedthat the switch 118 has a first contact formed by the contact 60 and a second contact formed by the lever 56 while the switch 120 has a first contact formed by the contact 92 and a second contact formed by the lever 76.
In operation, as the flywheel magnet 100 rotates past the coil 102, a sine wave voltage pattern is formed in the primary winding 104, and at or near the peak of the positive excursion the breaker points of the assembly 106 open, and the rapid change in current in the winding 104 produces a high voltage spike in the secondary winding 108, which fires the spark plug 110. The negative voltage excursion is not used for ignition but rather is used to power the safety module or circuit 112. Thus, with the engine 16 running and the traction drive control lever 56 and the collector-impeller drive control lever 76 in their respective drive-disengage positions, the lever 56 will be out of engagement with the contact 60 while the lever 76 is in engagement with the contact 92, the switches 118 and 120 accordingly respectively being open and closed. Since the diode 122 permits current flow therethrough during the negative voltage excursion, the relay coil 124 will be energized and the plunger 132 will be in rightwardly shifted position wherein the contact 134 is separated from the contacts 138. Thus, no current will be flowing through the ground lead 140.
If the lever 76 is then moved to its drive-engage position, the switch 120 will open and the relay coil 124 will be de-energized and the spring 136 will shift the plunger 132 leftwardly to engage the contact 134 with the contacts 138 to complete a grounding path though the lead 140 and diode 142. The engine 16 will then stop.
If the operator desires that the collector-impeller drive operate while the traction drive is disengaged, he needs only to hold the lever 56 in its intermediate drive-disengage position. In this position of the lever 56, it engages the contact 60 so that switch 118 is closed. The lever 76 can then be manipulated at will to engage and disengage the collector-impeller without the engine 16 stopping since the closed switch 118 will permit current to flow to energize the relay 126 and open the ground lead 140 in the manner described above.
Thus it will be appreciated that the safety module or circuit 112 acts as an interlock which prevents the collector-impeller drive from operating when it "senses" that the operator is not in a normal operating position behind the snowblower 10 with his hand in activating contact with the traction drive control lever 56. | A combined mechanical and electrical control for the traction drive and collector-impeller drive of a snowblower is provided which operates to disconnect the traction drive when the operator loosens his grip on a traction drive control lever to an extreme drive-disengage position to which it is constantly biased. Further, the control operates to stop the engine in the event that the operator loosens his grip on the level when the collector-impeller drive is engaged. However, the control is arranged such that the operator may manually hold the traction drive control lever in an intermediate drive-disengage position, while leaving the collector-impeller drive engaged without the engine stopping. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 07/267,527 entitled Drive Head Apparatus For A Rock Boring Machine, filed Nov. 4, 1988, and now abandoned.
BACKGROUND OF THE INVENTION
The rock boring machine drive head apparatus of the present invention has utility for use on rock boring equipment of types well-known in the rock boring field, such as the raise drill shown, for example, in Porter U.S. Pat. No. 3,754,605, Klein U.S. Pat. No. 3,797,587, West U.S. Pat. No. 3,800,887, and Porter U.S. Pat. No. 3,802,057. In such equipments, threaded drill sections are connected end for end to form the drill string and rotatably driven by the drive head while the drive head housing is hydraulically thrust downwardly, or upwardly as the case may be, to urge the drill into the ground being drilled. In such rock boring equipment, it is generally known and highly desirable to have a floating and swivelling bearing for the drive connection in order to absorb overturning forces transmitted by the drill string during drilling, and to guard against any unforeseen loads that might occur during the drilling operation. However, the provision of floating and swivelling bearings in the drive head is expensive, and when these parts become worn, replacement of the worn parts is also expensive and time consuming. The driving components utilized in connection with floating and swivelling bearings commonly include splined drive members, which normally wear in the recoiled position of the bearing, so that after extended use the remainder of the length of the splined teeth along the axial recoil slide path are usually in good condition while those at the recoiled end are worn.
SUMMARY OF THE INVENTION
Objects of this invention include the provision in a rock boring machine drive head apparatus with component structure allowing simple and economical reversal or replacement of worn drive and bearing components, and improved component design rendering the drill string driving elements, particularly the threaded connectors of the drive head into which the threaded drill string engages, less susceptible to wear, yet more resistant to breakage during extended use.
These and other objects, features and advantages of the invention will be apparent to those skilled in the art to which the invention is addressed from consideration of the typical embodiment of the invention herein illustrated and described.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a rock boring machine including a drive head embodying the present invention.
FIG. 2 is a front elevational view thereof.
FIG. 3 is a partially schematic, top plan view of the drive box and drive head assembly of the rock borer shown in FIGS. 1 and 2, corresponding to a view taken substantially along lines 3--3 of FIG. 1, with the frame and hydraulic cylinders omitted for simplicity.
FIG. 4 is a cross sectional view showing certain components of the drive box assembly, taken substantially along line 4--4 of FIG. 3.
FIG. 5 is a further cross sectional view, with certain parts shown in elevation, showing the driven components of the drive head assembly, taken substantially along line 5--5 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In general, the rock boring machine illustrated in FIG. 1 and 2, and in which the components are conventional per se and form no part of the present invention except for the unique construction and arrangement of certain components in the drive head assembly (as shown in FIG. 5), is comprised of a frame assmebly 10, base feet 12, turnbuckle assemblies 14 for adjusting the drill angle, a drive train assembly including electric motor 16, torque limiter 18, auxiliary gear box 20, drive box 22, and drive head 24. Hydraulic cylinders 26 provide thrust and the drive head 24 exerts rotary torque on threaded drill pipe (not shown) connected to either the downwardly facing drill string connector 28 (FIG. 5) or upwardly facing drill string connector 30 in the drive head 24, as more specifically discussed hereinafter.
FIG. 3 is a partially schematic, top plan view of the drive box 22 and drive head 24, and FIG. 4 is a lateral cross section through the axis of the drive box 22. As best seen in FIG. 4, input pinion 32 is rotatably driven by the output gear (not shown) of the auxiliary gear box 20 and is journaled in bearing 34. Splines on pinion gear 32 interengage with splines on first idler gears 36 journaled on pin 38, which in turn drive second idler gears 40 mounted on pins 42 (one being shown in FIG. 5). Gears 40 in turn, by splined interengagement, drive bull gear 44 in the drive head (FIG. 5).
Drive head 24 comprises a stationary housing 50 including bolted on top member 52, within which the rotated components of the drive head are supported by spherical roller thrust bearings 54 and tapered roller bearings 56. Rotated drive body 58 carries and is rotated by bull gear 44 about an axis of rotation indicated at 60 which is nominally coincident with the center axes of lower and upper drill string connectors 28, 30. Each drill string connector 28, 30 carries a respective spheroidal bearing member 62, 64, which is replaceably secured thereon and which is fabricated of relatively softer metal such as aluminum bronze alloy. The lower and upper drill string connectors 28, 30 are under resilient, compressive force exerted axially by compression spring 66 and the bearing body 62 on connector 28 is urged against and may float, i.e. swivel, somewhat with respect to spheroidal bearing surface 68 which is part of lower wrench body 70. The lower end assembly is completed by lower splash guard 72, seal ring 76 (against which seals 74 on the housing 50 ride), retainer 78, and splined ring 80, against which the conventional wrenching mechanism (not shown) used to connect and disconnect the drill pipe from the drill string connector 28 seats. As will be evident, the structural arrangement is such that the connector 28, although rotationally keyed to the drive body 58 by splines 82 in the body 58 and 84 on the connector 28, may move both axially and tiltably a limited degree relative to the drive body 58. Similarly, the spherical bearing 64 on the upper drill string connector 30, when the upper connector 30 is connected to an upwardly directed drill string and under its weight is urged downwardly against the force of spring 66, rides on the spheroidal bearing surface 86, and the upper drill string connector 30 can rock or swivel somewhat relative to the drive body 58 by reason of the configuration of the bearing 64 and bearing surface 86 and the driving connection between the drive body 58 and the drill string connector 30. According to the invention, this driving connection comprises a generally cylindrical spline insert 88 which has external splines 90 meshing with internal splines 92 on the drive body 58 and has internal splines 94 meshing with external splines on the connector 30. As will be evident, relative axial movement between the drive body 58 and drill string connector 30 can be accommodated by the splines 94, 96 without loss of driving connection between the body 58 and connector 30. As will also be evident, the ring-like spline insert 88 is readily reversible and readily replaceable.
The top end components around the upper drill string connector 30 include a wrench body 98, seal ring 100 against which seals on the stationary housing component 52 act, seal sleeve 104, and keyed spline ring 106, which functions as a component of the wrenching system for connecting and disconnecting a drill pipe from the drill string connector 30 in like manner as ring 80 associated with the lower drill string connector 28. As will be noted, the portion of the wrench body 98 surrounding the drill string connector 30 immediately above the cylindrical spline insert 88 serves to retain the spline insert in position yet is readily removable from the drill string connector 30. On its removal, the cylindrical splined insert 88 can simply be removed axially upwardly and reversed end for end to bring other portions of the splines 94 into normal engagement with the splines 96 on the connector 30. It is to be recognized in this regard that most of the wear on the splines 94 will occur in the lowermost portion thereof because this is the normal position of the connector 30 when under the load of an upwardly directed drill string and with upper bearing 64 engaging bearing surface 86. If the splines were formed directly in the drive body 58, when the splines became unduly worn it would normally require replacement of the entire drive body 58, whereas, with the construction shown, all that needs to be done is to reverse the splined sleeve 88. Similarly, the respective spheroidal bearings 62, 64 on the connectors 28, 30 are major points of wear and, with the component construction shown, the bearings 62, 64 are readily removable and replaceable without replacement of the entire respective drill string connector 28 or 30.
As will be understood, the drill string connectors 28, 30 are in the form of a box section of a threaded drill pipe of conventional form, and configured to receive the pin of a drill pipe section with drill pipe sections being made up to form the drill string, all in a conventional manner. Each such connector 28, 30 is secured to the opposite end of the coil spring 66 so that recoil can occur with the associated drive structures sliding inwardly into the housing 58 against the spring biasing, with appropriate axial movement occurring between the splines 82, 84 with respect to the lower connector 28 and between the splines 94, 96 with respect to the upper connector 30. A flexible hose and sliding piston interconnection 108 is also provided between the drill string connectors 28, 30 for use in certain operational instances to permit fluid injection into a drill string, if desired, through a swivel connection, also in a manner conventional per se.
In use, the spheroidal bearings 62, 64 and associated bearing surfaces 68, 86, if properly greased and kept dirt free, should not be wear parts. But should there be wear the inserts 62, 64 can be removed and replaced without the necessity for replacing the hardened steel components, i.e. the expensive drill string connector with treated bearing surfaces or replacing the heat treated bearing surfaces in the drive body 50 or lower body 70. The drive body 58 and the lower wrench body 70 in which the bearing surface 68 is formed can thus be fabricated to be more wear resistant with the intention that the inserts 62, 64 will take the wear if any wearing takes place.
It is also notable in the components configurations as shown in FIG. 5 that the drill string connectors 28, 30 have approximately uniform cross sectional thickness throughout. This in turn facilitates substantially uniform hardness throughout, i.e. with heat treatment hardening, in a manner conventional per se, occurring to substantially uniform depth throughout.
As indicated earlier, the splined insert 88 through which the upper drill string connector 30 is driven when the upper drill string connector is the operational drive string element, is axially removable upwardly out of its seating in the drive body 58 so that if wear occurs predominantly in one end portion of the splines 94 the insert 88 can simply be axially reversed or if it ultimately wears out it can be readily replaced without the necessity of replacing of the entire drive body 58. Although not shown, it will be understood that a similar drive insert or drive ring can be provided and be readily reversible or replaceable in like manner with respect to the lower drill string connector 28, i.e. by arranging such a reversible and replaceable externally and internally splined insert between the drive body splines 82 on drive body 58 and the splines 84 on the lower connector 28.
These and other modifications, adaptations and variations will occur to those skilled in the art to which the invention is addressed, within the scope of the following claims. | Drive head apparatus for driving the drill string of a rock boring machine, such apparatus comprising one or two drill string connectors (28) (30) having resilient means such as a coil spring (66) acting therebetween, with respective floating bearings (62) (64) separably secured thereto and with each bearing arrangement comprising respective cooperating, axially fixed bearing seating surfaces (68) (86). Each floating bearing (62) (64) is in the form of a softer metal insert replaceable on the associated connector (28) (30) without replacement of the drill string connector (28) (30). A splined cylindrical drive insert (88) rotatably drives the drill string connector and is separable from the drive body (58) in which it is seated and is axially reversible to swap wear ends or is readily replaceable without need for replacement of the entire drive body (58). | 4 |
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to coating processes. More particularly, this invention is directed to a physical vapor deposition process and apparatus for depositing ceramic coatings containing multiple oxides and elemental carbon and/or a carbon-based gas.
[0003] 2. Description of the Related Art
[0004] Certain components of the turbine, combustor and augmentor sections of a gas turbine engine are typically protected from their harsh thermal environments by a thermal barrier coating (TBC) formed of a ceramic material. Various ceramic materials have been proposed for TBC's, the most notable of which is zirconia (ZrO 2 ) that is partially or fully stabilized by yttria (Y 2 O 3 ). Binary yttria-stabilized zirconia (YSZ) is widely used as a TBC material because of its high temperature capability, low thermal conductivity and erosion resistance in comparison to zirconia stabilized by other oxides. YSZ is also preferred as a result of the relative ease with which it can be deposited by plasma spraying, flame spraying and physical vapor deposition (PVD) techniques. TBC's employed in the highest temperature regions of gas turbine engines are often deposited by PVD, particularly electron beam physical vapor deposition (EBPVD), which yields a columnar, strain-tolerant grain structure that is able to expand and contract without causing damaging stresses that lead to spallation. Similar columnar microstructures can be produced using other atomic and molecular vapor processes, such as sputtering (e.g., high and low pressure, standard or collimated plume), ion plasma deposition, and all forms of melting and evaporation deposition processes (e.g., cathodic arc, laser melting, etc.).
[0005] In order for a TBC to remain effective throughout the planned life cycle of the component it protects, it is important that the TBC material has and maintains a low thermal conductivity. However, the thermal conductivity of YSZ is known to increase over time when subjected to the operating environment of a gas turbine engine. To reduce and stabilize the thermal conductivity of YSZ, ternary YSZ systems have been proposed. For example, commonly-assigned U.S. Pat. No. 6,586,115 to Rigney et al. discloses a TBC of YSZ alloyed to contain certain amounts of one or more alkaline-earth metal oxides (magnesia (MgO), calcia (CaO), strontia (SrO) and barium oxide (BaO)), rare-earth metal oxides (lanthana (La 2 O 3 ), ceria (CeO 2 ), neodymia (Nd 2 O 3 ), gadolinium oxide (Gd 2 O 3 ) and dysprosia (Dy 2 O 3 )), and/or such metal oxides as nickel oxide (NiO), ferric oxide (Fe 2 O 3 ), cobaltous oxide (CoO), and scandium oxide (Sc 2 O 3 ). According to Rigney et al., when present in sufficient amounts these oxides are able to significantly reduce the thermal conductivity of YSZ by increasing crystallographic defects and/or lattice strains. In commonly-assigned U.S. patent application Ser. No. 10/064,785 to Darolia et al., a TBC of YSZ is deposited to contain a third oxide, elemental carbon, and potentially carbides. The resulting TBC is characterized by lower thermal conductivity that remains more stable during the life of the TBC as a result of stable porosity that forms when the elemental carbon and carbides within the TBC oxidize to form carbon-containing gases (e.g., CO).
[0006] While the incorporation of additional oxides and carbon-containing compounds into a YSZ TBC in accordance with Rigney et al. and Darolia et al. has made possible a more stabilized TBC microstructures, it can be difficult to deposit a TBC by an evaporation process to produce a desired and uniform composition if the additional oxide has a significantly different vapor pressure (e.g., an order of magnitude) than zirconia and yttria. For example, co-evaporation of YSZ and zirconium carbide (ZrC) as a source of carbides and/or carbon is complicated by the low partial pressure of ZrC, yielding a TBC that has an unacceptable nonuniform distribution of carbides. To avoid this result, separate ingots of YSZ and ZrC may be evaporated with a single electron beam using a controlled beam jumping technique, with the dwell time on each ingot being adjusted so that the energy output achieves the energy balance required to obtain compositional control of the vapor cloud that condenses on the targeted surface to form the desired coating. Alternatively, multiple electron guns can be operated at power levels suited for the particular material being evaporated by a given gun. Yet another approach disclosed in commonly-assigned U.S. patent application Ser. No. 10/064,887 to Movchan et al. involves regulating when vapors from one or more evaporation sources are permitted to condense on the surface being coated, such that deposition only occurs while the relative amounts of vapors within the vapor cloud are at levels corresponding to the desired coating composition.
[0007] It would be desirable if a process existed that simplified the co-evaporation of materials with different vapor pressures during the deposition of TBC's and other coatings.
SUMMARY OF INVENTION
[0008] The present invention provides a process and apparatus for depositing a ceramic coating, such as a thermal barrier coating (TBC) for a component intended for use in a hostile thermal environment, particular examples of which include turbine, combustor and augmentor components of a gas turbine engine. The process of this invention is particularly directed to an evaporation technique for depositing a TBC whose composition includes multiple oxide compounds and a carbon-based constituent, which as used herein includes elemental carbon, carbides, and carbon-based gases such as carbon monoxide (CO) and carbon dioxide (CO 2 ).
[0009] The invention generally entails the use of at least one evaporation source so as to provide multiple different oxide compounds and at least one carbide compound comprising carbon and an element. The evaporation source is evaporated to produce a vapor cloud that contacts and condenses on a surface to form a ceramic coating that comprises the oxide compounds, an oxide of the element of the carbide compound, and at least one of elemental carbon, a carbon-containing gas, and precipitates of the carbide compound. Such a process can be carried out with an apparatus comprising a coating chamber in which the one or more evaporation sources are present, and means for evaporating the evaporation source(s) to produce a vapor cloud that contacts and condenses on the surface to form the ceramic coating.
[0010] According to one aspect of the invention, the process is particularly suited for use when the oxide of the carbide compound element has a vapor pressure that is significantly different from the oxide compounds. If a YSZ coating is to be deposited, particularly notable examples of such oxides include ytterbia, neodymia, and lanthana, each of which has a sufficient absolute percent ion size difference relative to zirconium ions to produce significant lattice strains that promote lower thermal conductivities. As a result of their significantly different vapor pressures, it is difficult to produce a ceramic coating having a uniform and desired composition by simultaneously evaporating one or more ingots of YSZ and any one or more of these oxides. In accordance with this invention, these oxides can be codeposited with YSZ by evaporating their corresponding carbides, i.e., YbC 2 , NdC 2 , and LaC 2 , which dissociate during evaporation to form the oxide if sufficient oxygen is present within the vapor cloud to oxide the metal dissociated from the carbide. Furthermore, the process of this invention also advantageously co-deposits one or more carbon-based constituents that also evolve from evaporation of the carbide(s), promoting stable porosity within the coating.
[0011] Other objects and advantages of this invention will be better appreciated from the following detailed description.
BRIEF DESCRIPTION OF DRAWINGS
[0012] FIG. 1 is a schematic representation of an EBPVD apparatus using multiple evaporation sources to deposit a ceramic coating containing multiple oxide compounds, one of which has a significantly different vapor pressure than the remaining oxide compounds of the coating, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0013] The present invention is generally applicable to components subjected to high temperatures, and are therefore often formed of a superalloy material. The advantages of this invention are particularly applicable to TBC's for gas turbine engine components, such as the high and low pressure turbine nozzles and blades, shrouds, combustor liners and augmentor hardware. However, the teachings of this invention are more generally applicable to processes and apparatuses for depositing a ceramic coating. To provide the required thermal protection for a particular component, TBC's are typically deposited to a thickness of about 75 to about 300 micrometers, though lesser and greater thicknesses are foreseeable. Adhesion of the TBC to a superalloy substrate is typically promoted with the use of a bond coat, preferably an aluminum-rich composition such as an overlay coating of beta-phase NiAl intermetallic or MCrAlX alloy or a diffusion aluminide coating, though it is foreseeable that other bond coat materials and types could be used. These aspects of the invention are generally well known in the art, and therefore will not be discussed in further detail.
[0014] To achieve a strain-tolerant columnar grain structure, TBC's are deposited using a physical vapor deposition technique, such as EBPVD, though other evaporation techniques are possible and within the scope of this invention. The EBPVD process requires the presence of at least one evaporation source of the coating composition desired, and an electron beam at an appropriate power level to create a vapor of the evaporation source in the presence of the surface to be coated. FIG. 1 schematically represents a portion of an EBPVD coating apparatus 10 , including a coating chamber 12 in which a component 14 is suspended for coating. A TBC 16 is represented as having been deposited on the component 14 as a result of melting and vaporizing a pair of ingots 18 and 20 that, in combination, provide the constituents of the desired coating material. The ingots 18 and 20 are depicted as being evaporated with electron beams 28 produced by a single electron beam gun 30 , though multiple guns could be used for this purpose. The intensities of the beams 28 are sufficient to produce a vapor cloud that contacts and then condenses on the component 14 to form the TBC 16 . The vapor cloud evaporates from pools 22 and 24 of molten ingot material contained within reservoirs formed by crucibles 26 that surround the upper ends of the ingots 18 and 20 .
[0015] According to a preferred aspect of the invention, the thermal-insulating material of the TBC 16 is based on binary yttria-stabilized zirconia (preferably zirconia stabilized by about 3 to about 8 weight percent yttria), and further alloyed to contain at least a third metal oxide. The invention particularly pertains to the deposition by evaporation of YSZ-based coatings in which one or more of the additional metal oxides have a vapor pressure that differs significantly from zirconia and yttria, defined herein as at least an order of magnitude higher or lower than zirconia and yttria. Though not a necessary feature of the invention, the third oxide preferably has the effect of reducing and/or stabilizing the thermal conductivity of the TBC 16 . For this purpose, and in accordance with commonly-assigned U.S. Pat. No. 6,586,115 to Rigney et al., the third oxide preferably has a sufficient absolute percent ion size difference relative to zirconium ions to produce significant lattice strains that promote lower thermal conductivities. In accordance with commonly-assigned U.S. patent application Ser. No. 10/064,785 to Darolia et al., the TBC 16 also contains entrapped carbon-containing gases (e.g., carbon monoxide (CO) and/or carbon dioxide (CO 2 )) and possibly elemental carbon and/or carbides in the form of precipitate clusters, the thermal decomposition of which yields additional carbon-containing gas. In combination, the presence of entrapped CO and/or CO 2 , elemental carbon and/or carbide clusters, and one or more of the above-specified third metal oxides are believed to reduce the density and thermal conductivity of the YSZ TBC 16 .
[0016] According to the present invention, the ingots 18 and 20 can be evaporated to simultaneously deposit YSZ (or another base material), the third oxide, and the carbon-based constituent(s) in controllable desired proportions as a result of the third oxide and the carbon-based constituent(s) evolving during evaporation from a carbide of the metallic component of the third oxide. In preferred examples, one or more oxides of ytterbium, neodymium, and lanthanum (Yb 2 O 3 , Nd 2 O 3 , and La 2 O 3 ) are codeposited with YSZ by simultaneously evaporating the ingots 18 and 20 , one of which may be formed of YSZ while the other may be formed of one or more of YbC 2 , NdC 2 , and LaC 2 . During evaporation, the carbide dissociates and the dissociated metal oxidizes to deposit as the desired oxide on the component 14 to form the TBC 16 . In so doing, elemental carbon released as a result of dissociation of the carbide (and possibly the carbide itself) also deposits within the TBC 16 . During deposition, the third oxide preferably solutions into the YSZ to increase crystallographic defects and/or lattice strains that reduce thermal conductivity of the TBC 16 .
[0017] In accordance with Darolia, the presence of elemental carbon and/or carbide precipitates within the TBC 16 increases the porosity of the TBC 16 apparently as a result of a shadowing effect that occurs when two insoluble phases are deposited by PVD. More particularly, primary porosity is believed to be created surrounding deposited elemental carbon clusters (and possibly clusters of carbides, oxycarbides, etc., all of which are insoluble in YSZ) during EBPVD as a result of zirconia vapor flux being blocked from the immediate vicinity of the second phase clusters. Another benefit of co-deposition of carbon clusters (and possibly carbide clusters) by EBPVD has been observed to be the formation of many additional interfaces associated with sub-grain boundaries, possibly due to what appears to be related to the presence of carbon promoting the nucleation of new sub-grains and inhibiting diffusion processes of grain growth. The result is a continuous nucleation of new grains, which produces a fine sub-grained TBC structure with numerous interfaces that reduce thermal conductivity through the TBC grains. Open porosity levels observed within TBC deposited in accordance with this invention are well in excess of TBC deposited under identical conditions from only a YSZ source.
[0018] Fine secondary porosity occurs as a result of elemental carbon (and possibly carbides) precipitates within the TBC 16 reacting with oxygen to form carbon monoxide and/or another carbon-containing gas (e.g., carbon dioxide) during high temperature excursions (e.g., above about 950° C.). As a result of the primary porosity surrounding the deposited carbon, there is sufficient pore volume for carbon-containing gases to evolve and produce very fine pores (micropores) within the TBC 16 . As these gases form and some of the original primary porosity is lost as a result of shrinkage of smaller pores and growth of larger pores at the expense of smaller pores (pore coarsening and redistribution) during sintering, some of the gases are entrapped within the micropores. The entrapped gases are believed to counteract surface tension energies that are the driving force for the shrinkage of small pores during sintering. Therefore, in addition to reducing the density and thermal conductivity of the TBC 16 , the added fine porosity is thermally stable, i.e., less susceptible to shrinkage.
[0019] While not wishing to be held to any particular theory, the above-noted carbides are believed to provide a source of carbon within the slightly oxidizing atmosphere maintained within the EBPVD chamber 12 as a result of a controlled amount of oxygen being introduced into the chamber 12 above that necessary to ensure the deposition of ZrO 2 . Using the neodymium-based carbide (NdC 2 ) as an example, the coating reaction is believed to be:
[ZrO 2 +Y 2 O 3 ] matrix +2NdC 2 +7O→[ZrO 2 +Y 2 O 3 ] matrix +Nd 2 O 3 +4CO
[0020] In this reaction, carbon monoxide is indicated as evolving during dissociation of neodymium carbide (NdC 2 ), so as to be co-deposited with YSZ and neodymia (Nd 2 O 3 ). In addition or alternatively, clusters of elemental carbon and/or neodymium carbide may be co-deposited with YSZ, such that primary porosity forms around these clusters as a result of the shadowing effect during the EBPVD process. During subsequent heating, gaseous carbon monoxide then forms in situ as a result of oxidation of the carbon and/or neodymium carbide, resulting in new secondary porosity within the TBC 16 and its grains, as well as carbon monoxide (and/or carbon dioxide or another carboncontaining gas) entrapped within micropores that are remnants of the original primary porosity. Oxycarbides are also potential byproducts of the above reaction, and may serve to stabilize the micropore structure of the TBC 16 by anchoring and pinning the grain boundaries and pores of the TBC 16 .
[0021] If a significant amount of carbon monoxide forms as a result of oxidation of carbide precipitates within the TBC 16 , the carbides of the Group III metals of the Periodic Table can be more beneficial as compared to other carbides, such as ZrC, as these carbides tend to be relatively less stable. The basis for this belief is that carbide stability correlates with melting point, ZrC has a melting point of about 3427° C., while the melting points of the Group III carbides are believed to be in the range of about 2215° C. to about 2500° C. During the transformation of the carbide into the third oxide, a volume change is likely to occur that may lead to the formation of additional porosity during aging of the TBC 16 . For obtaining this benefit, the carbides of lanthanum, tantalum and neodymium are believed to be preferred as a result of their oxides being about 50 volume percent smaller than their carbides.
[0022] Additional benefits are possible with the present invention by co-evaporating carbides having vapor pressures and evaporation rates similar to zirconia, such that the evaporation process can be more readily controlled to yield a desired composition. For example, ZrC has a vapor pressure of one order of magnitude lower than ZrO 2 in the temperature range of 2500° C. to 3000° C., which appears to correlate with their different melting points (about 2701° C. for ZrO 2 and about 3427° C. for ZrC). As noted above, the melting points of carbides of the Group III metals are comparable to that of zirconia, such that the vapor pressures of these carbides are closer to zirconia than ZrC (i.e., less than one order of magnitude), making co-evaporation of zirconia and one or more of these carbides easier than co-evaporation of zirconia and ZrC. Such circumstances permit the carbide and zirconia (along with yttria) to be contained within a single ingot, so that multiple ingots are not required to deposit the TBC 16 .
[0023] While the invention has been described in terms of a preferred embodiment, it is apparent that other forms could be adopted by one skilled in the art. For example, instead of depositing the TBC by EBPVD, other vapor deposition processes could be used. Accordingly, the scope of the invention is to be limited only by the following claims. | A process and apparatus for depositing a ceramic coating, such as a thermal barrier coating (TBC) for a gas turbine engine component. The process deposits a coating whose composition includes multiple oxide compounds and a carbon-based constituent, e.g., elemental carbon, carbides, and carbon-based gases. The process uses at least one evaporation source to provide multiple different oxide compounds and at least one carbide compound comprising carbon and an element. The evaporation source is evaporated to produce a vapor cloud that contacts and condenses on the component surface to form the ceramic coating, and particularly so that the coating comprises the oxide compounds, an oxide of the element of the carbide compound, and the carbide compound and/or a carbon-containing gas. The process is carried out with an apparatus comprising a coating chamber in which the evaporation source is present, and a device for evaporating the evaporation source. | 2 |
FIELD OF THE INVENTION
The present invention relates to a printing sheet excellent in hiding power or reflectance and suitable for use in forming management labels or the like. The present invention further relates to a printed sheet having excellent heat resistance obtained from the printing sheet through thermal transfer printing.
BACKGROUND OF THE INVENTION
Conventional printed sheets for use as management labels in Braun tube production processes include: a sheet which is obtained by printing a glass-based green sheet with an ink containing glass particles to impart ink information thereto and is to be baked by burning; and a sheet obtained by forming inorganic particles into a sheet with a polyorganosiloxane and imparting ink information to the sheet. (See JP-A-7-334088 (the term “JP-A” as used herein means an “unexamined published Japanese patent application”), Japanese Patent Application No. 8-228667, Japanese Patent 2,654,753, WO 93/07844, and U.S. Pat. No. 5,578,365.)
However, it has been found that those prior art management labels applied to Braun tubes or the like cannot be utilized up to the recycling step for reclaiming reworkable parts from these adherends. Specifically, in the case of Braun tubes, reworkable parts are reclaimed through a salvage step in which the panel is separated from the funnel by immersion in hot nitric acid. Upon this immersion, however, the ink information imparted to the management label applied to the Braun tube disappears, making it impossible to manage reworkable parts based on the management label.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a printing sheet from which burned sheets, such as a management label effectively utilizable from the production of Braun tubes to the salvage thereof, which are excellent in chemical resistance, heat resistance, weatherability, hiding power or reflectance, etc., can be formed while satisfying advantages such as the bondability to curved surfaces which enables the printing sheet, after having been printed according to circumstances to impart information thereto, to be tightly bonded to adherends with heating, the suitability for expedient printed-sheet formation in which a variety of printed sheets necessary for the production of small quantities of many kinds of products can be formed therefrom in situ, etc. according to circumstances, and the ability to be easily and tightly bonded to adherends.
The present invention provides a printing sheet comprising a sheet made of a mixture comprising inorganic particles, an MQ resin, and a silicone rubber. The present invention further provides a printed sheet obtained by imparting ink information to the printing sheet by thermal transfer printing.
The printing sheet of the present invention is flexible and a variety of printed sheets can be formed therefrom according to circumstances by imparting ink information thereto by an appropriate printing technique, e.g., thermal transfer printing. These printed sheets can be satisfactorily adhered to, e.g., adherends having curved surfaces. Through a heat treatment, the printed sheets applied can be easily bonded tightly to the adherends to thereby form burned sheets satisfactorily retaining the imparted information. The burned sheets thus formed are excellent in chemical resistance, heat resistance, weatherability, hiding power or reflectance, etc., and can be effectively utilized as management labels or the like, for example, from the production of Braun tubes to the salvage thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of one embodiment of the printed sheet of the present invention.
FIG. 2 is a sectional view of one embodiment of the printing sheet of the present invention.
FIG. 3 is a plane view of another embodiment of the printing sheet of the present invention.
FIG. 4 is a sectional view of still another embodiment of the printing sheet of the present invention.
DESCRIPTION OF THE SYMBOLS
1 : Printing sheet
11 : Shape retention layer
12 : Reinforcing substrate
13 : Fine hole
2 : Ink information layer
3 : Pressure-sensitive adhesive layer
31 : Layer of pressure-sensitive adhesive dots
4 : Adherend
DETAILED DESCRIPTION OF THE INVENTION
The printing sheet of the present invention has a shape retention layer formed from a mixture comprising inorganic particles, an MQ resin, and a silicone rubber. The printed sheet is one obtained by imparting ink information to the shape retention layer by thermal transfer printing. An example of this printed sheet is shown in FIG. 1, wherein numeral 1 denotes a printing sheet, 2 ink information, 3 a pressure-sensitive adhesive layer disposed if desired, and 4 an adherend.
The printing sheet is not particularly limited as long as it comprises the shape retention layer in sheet form. The printing sheet can therefore have an appropriate constitution. Examples thereof include a constitution consisting of a shape retention layer alone (as in FIG. 1 ), a constitution comprising a shape retention layer 11 reinforced with a reinforcing substrate 12 as shown in FIG. 2, and a constitution having a pressure-sensitive adhesive layer.
The reinforced constitution may be formed by an appropriate method such as a method in which a shape retention layer is disposed on a reinforcing substrate as in FIG. 2, a method in which a reinforcing substrate is impregnated with a material for forming a shape retention layer, or a method in which a shape retention layer containing a reinforcing substrate disposed therein is formed. The reinforcing substrate may be an appropriate one. Examples thereof include coating layers of resins, resin films, fibers, fabrics, nonwoven fabrics, metal foils, and nets.
The reinforcing substrate may be made of a material which disappears upon heating, such as a polymer, e.g., a polyester, polyimide, fluororesin, or polyamide, or may be made of a material which does not disappear upon heating, such as a glass, ceramic, or metal.
The inorganic particles for use in forming the shape retention layer serve to improve heat resistance (generally up to about 500° C., preferably up to about 800° C.) and to determine the background color of printed sheets to be obtained from the printing sheet. Suitable inorganic particles can hence be used, such as metal particles or ceramic particles. One kind of inorganic particles or a combination of two or more kinds of inorganic particles can be used. Although the particle diameter of the inorganic particles is generally 50 μm or smaller, preferably from 0.05 to 20 μm, it is not limited thereto. To incorporate a flaky powder prepared by adhering inorganic particles to thin platy bases such as mica is effective in improving hiding power or reflectance.
Examples of inorganic particles generally used include white particles such as particles of silica, titania, alumina, zinc white, zirconia, calcium oxide, mica, potassium titanate, and aluminum borate. Examples thereof further include metal compounds, such as carbonates, nitrates, and sulfates, which are oxidized at temperatures not higher than the temperature to be used for the heat treatment of the printed sheet to thereby change into such oxide type white ceramics. Especially preferably used among these from the standpoints of whiteness, sinter strength, etc. are acicular crystals such as those of potassium titanate or aluminum borate.
Other examples of the inorganic particles include red particles such as manganese oxide-alumina, chromium oxide-tin oxide, iron oxide, and cadmium sulfide-selenium sulfide, blue particles such as cobalt oxide, zirconia-vanadium oxide, and chromium oxide-divanadium pentoxide, and black particles such as chromium oxide-cobalt oxide-iron oxide-manganese oxide, chromates, and permanganates.
Examples of the inorganic particles further include yellow particles such as zirconium-silicon-praseodymium, vanadium-tin, and chromium-titanium-antimony, green particles such as chromium oxide, cobalt-chromium, and alumina-chromium, and pink particles such as aluminum-manganese and iron-silicon-zirconium.
The MQ resin can comprise an appropriate polymer which is known as, e.g., a tackifier for silicone-based pressure-sensitive adhesives and comprises monofunctional units M represented by the general formula R 3 SiO— and tetrafunctional units Q represented by the formula Si(O—) 4 . In the above general formula, each R may have an appropriate structural unit, for example, an organic group, e.g., an aliphatic hydrocarbon group such as methyl, ethyl, or propyl, an aromatic hydrocarbon group such as phenyl, or an olefin group such as vinyl, or a hydrolyzable group such as hydroxyl. A preferred MQ resin is one excellent in shape retention.
The silicone rubber also is not particularly limited and an appropriate one may be used. Various modified silicone rubbers are usable, such as phenol-modified, melamine-modified, epoxy-modified, polyester-modified, acrylic-modified, and urethane-modified silicone rubbers. A preferred silicone rubber is one excellent in shape retention and flexibility.
The printing sheet can be formed by, for example, the following method. Inorganic particles of one or more kinds are mixed with at least one MQ resin and at least one silicone rubber by means of a ball mill or the like using an organic solvent or the like if necessary. The resulting liquid mixture is spread by an appropriate technique, if desired, on a support such as a reinforcing substrate or separator, and the coating is dried to form the target sheet.
In forming the printing sheet, the proportion of the MQ resin and the silicone rubber to the inorganic particles can be suitably determined according to the handleability of the printing sheet, the strength and hiding power of printed sheets, etc. However, the sum of the resin and rubber is generally from 20 to 800 parts by weight, preferably from 30 to 500 parts by weight, more preferably from 100 to 300 parts by weight, per 100 parts by weight of the inorganic particles.
The proportion of the MQ resin to the silicone rubber can be suitably determined according to sinter strength, chemical resistance, etc. of the sheet. However, the silicone rubber is used in an amount of generally from 1 to 1,000 parts by weight, preferably from 3 to 500 parts by weight, more preferably from 5 to 200 parts by weight, per 100 parts by weight of the MQ resin If the MQ resin is incorporated in an insufficient amount, the sheet has a poor sinter strength. If the silicone rubber is incorporated in an insufficient amount, the sheet has poor resistance to chemicals such as hot nitric acid.
The organic solvent which can be used if desired may be an appropriate one. In general, use is made of toluene, xylene, butyl carbitol, ethyl acetate, butyl Cellosolve acetate, methyl ethyl ketone, methyl isobutyl ketone, or the like. Although the liquid mixture is not particularly limited, it is preferably prepared so as to have a solid concentration of from 5 to 85% by weight from the standpoints of spreadability, etc. In preparing the liquid mixture, appropriate additives can be incorporated, such as a dispersant, plasticizer, and combustion aid.
A preferred method for spreading is one having the excellent ability to regulate coating film thickness, such as the doctor blade method or gravure roll coater method. It is preferred to sufficiently defoam the liquid mixture, for example, by adding a defoamer so as to form a bubble-free spread layer. Although the thickness of the printing sheet or shape retention layer to be formed is suitably determined, it is generally from 5 μm to 5 mm, preferably from 10 μm to 1 mm, more preferably from 20 to 200 μm.
The printing sheet of the present invention can be made porous for the purpose of enabling decomposition gases resulting from heating to volatilize smoothly or for other purposes. There are cases where printed sheets swell due to decomposition gases resulting from heating especially when the printing sheet has a pressure-sensitive adhesive layer for provisional bonding. This swelling can be avoided by forming a porous printing sheet.
For forming a porous printing sheet, an appropriate method can be used, such as a method in which, as shown in FIG. 3, many fine holes 13 are formed in a printing sheet 1 by punching or the like or a method in which a woven fabric, a nonwoven fabric, a metal foil having many fine holes, a net, or the like is used as a reinforcing substrate.
An organic compound or other substances can be incorporated if desired into the shape retention layer in order to improve ink fixability or for other purposes. Examples of the organic compound include hydrocarbon polymers, vinyl or styrene polymers, acetal polymers, butyral polymers, acrylic polymers, polyester polymers, urethane polymers, cellulosic polymers, and various waxes.
It is especially preferred to incorporate a cellulosic polymer such as ethyl cellulose from the standpoints of improving ink fixability in thermal transfer printing, improving the strength of the printing sheet, etc. The use amount of the organic compound is generally from 5 to 200 parts by weight, preferably from 10 to 100 parts by weight, per 100 parts by weight of the sum of the MQ resin and the silicone rubber. However, the use amount thereof is not limited thereto.
A melting-point depressant for silica can be further incorporated. This melting-point depressant may be an appropriate substance which is capable of lowering the melting point of silica. Examples thereof include alkali metals such as potassium, sodium, and lithium. Although such an alkali metal can be incorporated, for example, in the form of a powder of the metal, it is preferred in the present invention that the melting-point depressant be dispersed as evenly as possible throughout the shape retention layer. From this standpoint, finer particles are advantageous. It is therefore possible to incorporate an alkali metal as a compound thereof which is easily available as fine particles. The kind of this compound is not particularly limited and an appropriate one may be used, such as, e.g., hydroxide or carbonate.
The use amount of the melting-point depressant for silica can be suitably determined according to the strength of the burned sheet to be obtained, etc. The melting-point depressant for silica functions in the following manner. When a printed sheet is burned at about 400° C. or higher as stated above, the MQ resin is deprived of its organic groups, such as silicon-bonded methyl groups, and thus changes into fine silica particles. These silica particles undergo sintering, during which the melting-point depressant serves to lower the melting point of the silica to thereby enhance the sinter strength of the resulting sheet.
If a melting-point depressant for silica is not incorporated, the resultant sintered sheet has a surface hardness in terms of pencil hardness of about 4 H, indicating that the sinter has poor strength and the surface thereof is readily broken by mechanical impacts. Namely, the ink information on this sintered sheet is apt to be burned out. In contrast, by incorporating KOH into a printing sheet in an amount of 4,000 ppm, the surface hardness of the sheet can be heightened to 9 H or higher, which corresponds to that of ceramic labels.
Consequently, a melting-point depressant for silica can accomplish the purpose of the incorporation thereof when incorporated in an amount as small as at least 0.01 ppm of the printing sheet as determined by the water extraction method. The incorporation amount thereof is regulated according to the strength of the burned sheet to be obtained, etc. The strength of the burned sheet is influenced also by the diameter of the aforementioned fine silica particles formed from the MQ resin. The particle diameter thereof is theoretically thought to be about 1 nm. As long as such fine particles are contained even in an amount as small as below 1% by weight based on the printing sheet, a burned sheet can be obtained as a strong sinter even when burning is conducted at a temperature of 500° C. or lower.
From the standpoints of the strength of the burned sheet to be obtained and the formability of the printing sheet, etc. in view of the diameter of the fine silica particles and the attainment of a reduction in burning temperature, the incorporation amount of the melting-point depressant for silica is preferably 0.1 ppm or larger, more preferably from 50 to 10,000 ppm, most preferably from 100 to 5,000 ppm, per 100 parts by weight of the MQ resin.
The printing sheet of the present invention is preferably used in the following application. The printing sheet is provisionally bonded to an adherend either as it is or as a printed sheet obtained by imparting information thereto. This printing sheet or printed sheet is heated to thereby tightly bond the same to the adherend. In conducting this heat treatment, a method can be employed that a material to be fixed (e.g., aluminum plate) is placed (adhered) on the printing sheet, the laminate is heated, and the heated product is fixed to an adherend.
There are cases where the printing sheet or printed sheet of the present invention can be provisionally bonded to an adherend by means of its own pressure-sensitive adhesive properties. However, a pressure-sensitive adhesive layer may be formed on the sheet for the purpose of improving suitability for provisional bonding or for other purposes. The pressure-sensitive adhesive layer can be formed in an appropriate stage before the printing sheet or printed sheet is provisionally bonded to an adherend and heated. Namely, it may be formed before information is imparted to the printing sheet to obtain a printed sheet, or may be formed after a printed sheet has been thus obtained.
As a material for forming a pressure-sensitive adhesive layer, an appropriate pressure-sensitive adhesive material can be used, such as a pressure-sensitive adhesive based on a rubber, acrylic, silicone, or vinyl alkyl ether. For forming the pressure-sensitive adhesive layer, an appropriate method employed in the formation of pressure-sensitive adhesive tapes and the like can be used. Examples thereof include a method in which a pressure-sensitive adhesive material is applied to the printing sheet or printed sheet by an appropriate coating technique using, e.g., a doctor blade or gravure roll coater and a method in which a pressure-sensitive adhesive layer is formed on a separator by such a coating technique and the adhesive layer is transferred to the printing sheet or printed sheet.
It is also possible to form a pressure-sensitive adhesive layer made up of dots of a pressure-sensitive adhesive, for the purpose of enabling decomposition gases resulting from heating to volatilize smoothly or for other purposes. In this case, a more preferred constitution is one in which the printing sheet is porous as described above. In FIG. 4 is shown a printing sheet 1 having a pressure-sensitive adhesive layer 31 made up of pressure-sensitive adhesive dots. Such a pressure-sensitive adhesive layer can be formed by a coating technique such as, e.g., the rotary screen process.
Although the thickness of the pressure-sensitive adhesive layer to be formed can be determined according to the intended use thereof, etc., it is generally from 1 to 500 μm, preferably from 5 to 200μm. It is preferred to cover the thus-formed pressure-sensitive adhesive layer with a separator or the like in order to prevent fouling, etc. until the adhesive layer is provisionally bonded to an adherend. For provisionally bonding the printing sheet or printed sheet to an adherend, use can be made of a method in which the sheet is automatically applied by a robot or the like.
A printed sheet can be obtained by an appropriate method such as, e.g., a method in which ink information or engraved information comprising either holes or projections and recesses is imparted to the printing sheet or a method in which an appropriate shape is punched out of the printing sheet. It is also possible to form a printed sheet having a combination of the aforementioned information elements or having a combination of different kinds of information formed by any of other various methods.
The ink information can be imparted by handwriting or by an appropriate printing technique such as coating through a patterned mask, transfer of a pattern formed on a transfer paper, or printing with a printer. Preferred of these is printing with a printer, in particular, a thermal transfer printer, because this printing technique is advantageous, for example, that any desired ink information can be efficiently imparted highly precisely according to circumstances.
An appropriate ink can be used, such as, e.g., an ink containing a colorant such as a pigment, in particular, a heat-resistant colorant such as an inorganic pigment. The ink may contain a glass frit or the like so as to have improved fixability after heat treatment or for other purposes. An ink sheet such as a printing ribbon for use in thermal transfer printers can be obtained, for example, by adding a binder such as a wax or polymer to such an ink and causing a supporting substrate comprising a film, a fabric, or the like to hold the resultant ink composition. Consequently, a known ink or an ink sheet containing the same can be used in thermal transfer printing or the like.
The ink information to be imparted is not particularly limited, and appropriate ink information may be imparted, such as, e.g., characters, a design pattern, or a bar code pattern. In the case where an identification label, e.g., a management label, is formed or in similar cases, it is preferred to impart ink information so that a satisfactory contrast or a satisfactory difference in color tone is formed between the printing sheet and the ink information after heat treatment.
The step of imparting ink information or a shape to the printing sheet may be conducted either before or after the printing sheet is provisionally bonded to an adherend. In the case where a printer is used for imparting ink information, the generally employed method is to prepare beforehand a printed sheet having ink information and provisionally bond the same to an adherend.
The heat treatment of the printing sheet or printed sheet which has been provisionally bonded to an adherend can be conducted under suitable conditions according to the heat resistance of the adherend, etc. The heating temperature is generally 800° C. or lower, preferably from 200 to 650° C., more preferably from 250 to 550° C. During the heat treatment, the organic components including those contained in the pressure-sensitive adhesive layer disappear and the MQ resin and silicone rubber contained in the printing sheet cure while uniting with the ink information. As a result, a burned sheet tightly bonded to the adherend is formed
The printing sheet or printed sheet of the present invention can be advantageously used in various applications such as, e.g., the printing or coloring of various articles including pottery, glassware, ceramics, metallic products, and enameled products and the impartation of identification information or identification marks comprising bar codes to such articles.
In particular, the printing or printed sheet can be advantageously used in forming management labels or the like which are utilizable, e.g., from the production of Braun tubes to the reclamation of reworkable parts from recycled Braun tubes, because the burned sheet obtained from the printing or printed sheet has such an excellent chemical resistance that it withstands immersion in hot nitric acid and satisfactorily retains the ink information. The adherend may have any shape such as, e.g., a flat shape or a curved shape as of containers.
The present invention will be explained below in more detail by reference to the following Examples, but the invention should not be construed as being limited thereto.
EXAMPLE 1
With toluene were evenly mixed 130 parts by weight (hereinafter all parts are by weight) of an MQ resin, 30 parts of a silicone rubber (both manufactured by Shin-Etsu Chemical Co., Ltd.), 80 parts of potassium titanate, and 60 parts of ethyl cellulose. The resulting dispersion was applied on a PET film having a thickness of 75 μm with a doctor blade. The coating was dried to form a shape retention layer having a thickness of 65 μm. Thus, a printing sheet was obtained.
On the other hand, a toluene solution containing 100 parts of poly(butyl acrylate) having a weight-average molecular weight of about 1,000,000 was applied with a doctor blade on a separator which was a 70 μm-thick glassine paper treated with a silicone release agent. The coating was dried to form a pressure-sensitive adhesive layer having a thickness of 20 μm. This adhesive layer supported on the separator was applied to the shape retention layer, and the PET film was peeled off to obtain a printing sheet having a pressure-sensitive adhesive layer.
Subsequently, ink information comprising a bar code was imparted to the printing sheet using a thermal transfer printer and a commercial ink ribbon holding a wax-based ink containing a black metal oxide pigment and a bismuth glass. Thus, a printed sheet was obtained.
EXAMPLE 2
A printing sheet and a printed sheet were obtained in the same manner as in Example 1, except that aluminum borate was used in place of the potassium titanate.
COMPARATIVE EXAMPLE 1
A printing sheet and a printed sheet were obtained in the same manner as in Example 1, except that the silicone rubber was replaced with the same MQ resin as in Example 1.
COMPARATIVE EXAMPLE 2
A printing sheet and a printed sheet were obtained in the same manner as in Example 1, except that the MQ resin was replaced with the same silicone rubber as in Example 1.
EVALUATION TESTS
The separator was peeled from each of the printed sheets obtained in the Examples and Comparative Examples. Each printed sheet was provisionally bonded to a glass plate through the pressure-sensitive adhesive layer and then heated at 470° C. for 30 minutes (in air). As a result, glass plates were obtained which each had, tightly bonded thereto, a burned sheet having clear ink information comprising a black bar code on a white background. These glass plates were subjected to the following tests. By the heat treatment, the ethyl cellulose contained in each printing sheet and the other organic components including those contained in the pressure-sensitive adhesive layer were burned out. Each burned sheet remaining after the heat treatment was a cured sheet formed from the MQ resin and/or the silicone rubber.
Sinter Strength
The surface of each burned sheet was rubbed with a cotton cloth to examine the ink information fixing strength and the glass plate bonding strength of the burned sheet. These properties were evaluated based on the following criteria.
Good: Burned sheet wholly remained adherent and ink information retained the same readability as before the test.
Poor: Burned sheet rubbed off at least partly and ink information became unreadable.
Reflectance
Reflectance of the white background in each burned sheet was measured with respect to light having a wavelength range of from 400 to 800 nm.
Chemical Resistance
Each burned sheet was immersed together with the glass plate in 15% nitric acid solution at 80° C. for 2 minutes, subsequently taken out thereof, and then evaluated by the same method as in the sinter strength test given above.
The results obtained are shown in Table 1.
TABLE 1
Comparative
Comparative
Example 1
Example 2
Example 1
Example 2
Sinter
Good
Good
Good
Poor
strength
Reflect-
80
50
80
80
ance (%)
Chemical
Good
Good
Poor* 1
Poor* 2
resistance
* 1 Ink information disappeared because a surface layer of the burned sheet rubbed off.
* 2 Ink information became blurred.
EXAMPLE 3
With toluene were evenly mixed 130 parts by weight (hereinafter all parts are by weight) of an MQ resin, 30 parts of a silicone rubber (both manufactured by Shin-Etsu Chemical Co., Ltd.), 0.4 parts of potassium hydroxide, 80 parts of potassium titanate, and 60 parts of ethyl cellulose. The resultant dispersion was applied on a polyester film having a thickness of 75 μm with a doctor blade. The coating was dried to form a shape retention layer having a thickness of 65 μm. Thus, a printing sheet was obtained.
On the other hand, a toluene solution containing 100 parts of poly(butyl acrylate) having a weight-average molecular weight of about 1,000,000 was applied with a doctor blade on a separator which was a 70 μm-thick glassine paper treated with a silicone release agent. The coating was dried to form a pressure-sensitive adhesive layer having a thickness of 20 μm. This adhesive layer supported on the separator was applied to the shape retention layer, and the polyester film was peeled off to obtain a printing sheet having a pressure-sensitive adhesive layer.
Subsequently, ink information comprising a bar code was imparted to the printing sheet using a thermal transfer printer and a commercial ink ribbon holding a wax-based ink containing a black metal oxide pigment and a bismuth glass. Thus, a printed sheet was obtained.
EXAMPLE 4
A printing sheet and a printed sheet were obtained in the same manner as in Example 3, except that aluminum borate was used in place of the potassium titanate.
COMPARATIVE EXAMPLE 3
A printing sheet and a printed sheet were obtained in the same manner as in Example 3, except that the potassium hydroxide was omitted.
COMPARATIVE EXAMPLE 4
A printing sheet and a printed sheet were obtained in the same manner as in Example 3, except that the silicone rubber was replaced with the same MQ resin as in Example 3.
COMPARATIVE EXAMPLE 5
A printing sheet and a printed sheet were obtained in the same manner as in Example 3, except that the MQ resin was replaced with the same silicone rubber as in Example 3.
Evaluation Tests
The separator was peeled from each of the printed sheets obtained in the above Examples and Comparative Examples. Each printed sheet was provisionally bonded to a glass plate through the pressure-sensitive adhesive layer and then heated at 470° C. for 30 minutes (in air). As a result, glass plates were obtained which each had, tightly bonded thereto, a burned sheet having clear ink information comprising a black bar code on a white background. These glass plates were subjected to the following tests. By the heat treatment, the ethyl cellulose contained in each printing sheet and the other organic components including those contained in the pressure-sensitive adhesive layer were burned out. Each burned sheet remaining after the heat treatment was a cured sheet comprising silica formed from the MQ resin and/or the silicone rubber.
Pencil Hardness
The pencil hardness of the surface of each burned sheet was measured in accordance with JIS K 5400.
Sinter Strength
The surface of each burned sheet was rubbed with a cotton cloth to examine the ink information fixing strength and the glass plate bonding strength of the burned sheet. These properties were evaluated based on the following criteria.
Good: Burned sheet wholly remained adherent and the ink information retained the same readability as before the test.
Poor: Burned sheet rubbed off at least partly and the ink information became unreadable.
Reflectance
The reflectance of the white background in each burned sheet was measured with respect to light having a wavelength range of from 400 to 800 nm.
Chemical Resistance
Each burned sheet was immersed together with the glass plate in 15% nitric acid solution at 80° C. for 2 minutes, subsequently taken out thereof, and then evaluated by the same method as in the sinter strength test given above.
The results obtained are shown in Table 2 below.
TABLE 2
Comparative
Comparative
Comparative
Example 3
Example 4
Example 3
Example 4
Example 5
Pencil hardness
≧9 H
≧9 H
4 H
≧9 H
3 H
Sinter strength
Good
Good
Good
Good
Poor
Reflectance (%)
80
50
80
80
80
Chemical resistance
Good
Good
Scratchy
Disappeared
Blurred
Scratchy: Pattern partly disappeared.
Blurred: Pattern became blurred.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | A printing sheet is disclosed from which burned sheets, such as, e.g., a management label effectively utilizable from the production of Braun tubes to the salvage thereof, which are excellent in chemical resistance, heat resistance, weatherability, hiding power or reflectance, etc., can be formed while satisfying advantages such as the bondability to curved surfaces which enables the printing sheet, after having been printed according to circumstances to impart information thereto, to be tightly bonded to adherends with heating, the suitability for expedient printed-sheet formation in which a variety of printed sheets necessary for the production of small quantities of many kinds of products can be formed therefrom in situ, etc. according to circumstances, and the ability to be easily and tightly bonded to adherends. The printing sheet ( 1 ) comprises a sheet made of a mixture comprising inorganic particles, an MQ resin, and a silicone rubber. Also disclosed is a printed sheet obtained by imparting ink information ( 2 ) to the printing sheet by thermal transfer printing. | 1 |
This is a continuation of application Ser. No. 653,983, filed Feb. 11, 1991, now U.S. Pat. No. 5,245,808, which is a file wrapper continuation of Ser. No. 444,666, filed Dec. 1, 1989, now abandoned.
TECHNICAL FIELD
The present invention generally relates to an adhesively glazed curtainwall system and more particularly relates to a butt-glazed curtainwall system including mechanical retention members which retain vertical edges of glass panels while providing minimal sight lines, thus permitting glazing and weathersealing to be accomplished from the interior side of the curtainwall.
BACKGROUND OF THE INVENTION
In building structures, it is often aesthetically desirable to cover large portions of the outside of the structures with as much glass and as little outside framing elements as possible, thereby providing the structures with a smooth and unbroken outside surface appearance. Therefore, it is known in the art to provide a structural adhesive bond between the building structure and the inside surfaces of glass panels to attach the panels to the building structure, thus reducing or eliminating the need for permanent outside retention members. Such bonding configurations are commonly known as "Structural Silicone Glazing" or "SSG" systems.
Typical SSG systems fall into two major classes: two-sided and four-sided. Four-sided SSG systems typically include a plurality of vertical structural mullions in combination with a plurality of horizontal structural mullions, which combine to form a mullion framework having a plurality of panel-shaped openings which are slightly smaller than the glass panels to be supported. The mullion framework is fixed about the exterior of a building structure. Each glass panel is positioned adjacent to the exterior surface of the mullion framework and over a corresponding panel-shaped opening by a plurality of temporary retaining clips, such that the edges of the panel slightly overlap the panel-shaped opening and a small gap exists between the inside surfaces of the glass panel and the framework. Structural adhesive, typically structural silicone, is then applied into the gap. After the silicone adhesive cures, it provides a structural bond between the mullion framework and the glass panel which can completely support the glass panel without any aid from the temporary retaining clips or other outside retention means. For weatherproofing purposes, additional silicone adhesive is then applied from the outside of the building into gaps created by the abutting edges of the adjacent glass panels. Disadvantageously, this "weatherbead" must be applied from the exterior of the building.
Two-sided SSG systems differ in that a structural adhesive bond as described above is provided along two (usually vertical) opposing edges of the glass panels. In two-sided SSG systems, the two edges not being structurally bonded to the mullion framework are retained by other means. This is normally done by conventional window glazing means which enclose the entire edge of the glass panels, thus not providing the smooth continuous appearance of four-sided SSG systems. As in the four-sided SSG systems, additional silicone adhesive must be applied from the outside of the building into the gap created by the abutting edges of the glass panels.
Although such SSG systems are in demand, the cost for such systems is high. As discussed above, in four-sided SSG systems, temporary mechanical retentioners for the glass panels must be installed to allow the structural silicone adhesive to cure, and then must be removed after the curing process. Sealant must then be added to cover holes left behind by the temporary fasteners. As such installation and removal processes must be performed from the exterior of the building structure, these processes are typically labor- and cost-intensive, as scaffolding must be installed to provide access to the exterior of the building. In both two- and four-sided systems, the weatherproofing joint must be installed from the building exterior, and the quality of the weatherproofing joint is highly dependent upon the skill of the field laborer installing the glass and applying the sealant.
Safety is also a concern associated with SSG systems, as high reliance is placed upon structural bonding. The structural adhesive is subject to rupture under certain loading conditions, such as high negative pressure on the lee side of the building during periods of strong winds. Such a rupture can cause a glass panel to fall from a building and crash to the ground, possibly causing catastrophic personal injury and property damage.
Various approaches to overcome the above deficiencies have been proposed, such as that disclosed in U.S. Pat. No. 4,650,702, wherein each pane of glass of the curtainwall system has a prebonded structural interface adhered along at least two of its edges. The structural interface is clipped onto the face of the mullion framework during installation to fasten the pane to the mullion framework. Also disclosed is a non-structural weatherseal between adjacent panels which is installed from the interior side of the curtainwall system.
U.S. Pat. No. 4,562,680 discloses a butt glazing system including a specially configured frame member with a front wall forming an angle of at least 135 degrees. A semicircular channel open along its forward portion is formed at the apex of the angled front wall. A special elongate mullion has a gasket formed along its front edge. The rear edge of the mullion insert has a T-shaped connector portion formed thereon. The "head" of the T-shaped connector portion is wider than the opening of the front of the semicircular channel, such that the head of the connector can be inserted into the channel only by introducing it at an angle and rotating it into place. When so installed, the mullion insert is held within the semicircular channel as long as it is not permitted to rotate relative to the channel. To install a curtainwall according to this system, a first glazing panel is positioned against the end mullion and the adjacent interior mullion from inside the building. A mullion insert as described is then fastened to a chevron-shaped mullion as described, and pivoted such that the gasket portion of the insert abuts the edge of the first panel. A second panel is then positioned against the opposite side of the mullion insert and against the next adjacent mullion. The glazing procedure is then repeated progressively.
Although such systems include advantages, none have proven so successful as to attain industry acceptance. Therefore, efforts continue to solve this problem.
Thus, there is a recognized need to provide a system for structural silicone glazing wherein glazing and weatherproofing may be accomplished from the interior side of the building.
There is also a need to provide such a system which is easy to install, tolerates non-regular or non-plumb installation of glass, and provides improved safety characteristics.
SUMMARY OF THE INVENTION
As will be seen, the present invention solves the above needs associated with prior art butt-glazed curtainwall systems. Stated generally, the present invention comprises a retainer for accepting edges of glass panels and retaining the edges relative to a framing member, comprising an elongate retainer profile having a generally H-shaped transverse cross section, thereby forming a pair of elongate U-shaped retaining channels, the first of the retaining channels configured to accept an edge of a first of the glass panels, and the second of the retaining channels configured to accept an edge of a second of the glass panels, panel securing means for securing the first and second panel edges within the first and second channels, respectively, and profile securing means for securing the profile coextensively along the framing member, such that one side of the pair of retaining channels is urged against the framing member.
The elongate retaining channels provide means for retaining glass panels in place during the application of structural adhesive, and also serve as means for retaining the edges of glass panel in the event that structural adhesive should fail. Weathersealing is also provided by the existence of strategically placed pads intended for contact with the smooth glass surface.
Therefore it is an object of this invention to provide a retainer and weatherseal between adjacent glass panels in a curtainwall framing system having structurally bonded glazing.
It is another object to provide such a retainer which permits structurally bonded glazing to be installed on curtainwall framing entirely from the interior of a building and which eliminates any need to weather seal the glass panels working from the building exterior.
It is another object to provide such a retainer which retains adjacent glass panels while their structural adhesive bonding cures, thereby eliminating necessity for temporary retainers.
It is another object to provide such a retainer which aesthetically does not detract from the smooth, unbroken appearance of structurally bonded glazing.
It is another object to provide such a retainer which enhances the structural integrity of the adhesively bound glass panels without detracting from the smooth, unbroken appearance of the glass panels.
It is another object to provide such a retainer which tolerates non-plumb installation of glass panels.
Other objects, features and advantages of the invention will become apparent upon reading the following detailed description in conjunction with the drawings and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view of a representative portion of the curtainwall framing system as viewed from the exterior.
FIG. 2 is a horizontal cross-sectional view through a curtainwall framing system according to a first preferred embodiment of the present invention, including a vertical framing member, a first preferred embodiment retainer, and two glass panels. However, spacers and structural adhesive according to the present invention are not yet in place.
FIG. 3 is similar in view to FIG. 2, except that the spacers and structural adhesive are shown in place.
FIG. 4 is an isolated cross-sectional view of a first preferred embodiment of the retainer of the present invention.
FIG. 5 is a partial close up view of that shown in FIG. 4.
FIG. 6 is an isolated cross-sectional view of a second preferred embodiment of the retainer of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings, in which like numerals represent like parts throughout the separate views, FIG. 1 shows a representative portion of a "two-sided" SSG curtainwall framing system including vertical framing members 10, horizontal framing members 13, horizontal exterior retention members 15, a glass panel or panels 19, and vertical retainers 28.
Vertical framing members 10 may be linked together by means known in the art to horizontal framing members 13 to form a substantially rigid framework to which the plurality of glass panels 19 may be attached.
The weight of each of the glass panels 19 is supported by shelves attached to or an integral part of the horizontal frame members 13, as known in the art. As this is a two-sided SSG system, two edges of each glass panel, in this case the horizontal edges, are retained by horizontal exterior retention members 15, such as is known in the art. The other, in this case, vertical edges of the glass panels are captured and-retained by retainers 28, as discussed in further detail later in this application. FIG. 3 shows a transverse cross section through a vertical framing member 10, an elongate profile extruded of architectural aluminum. Adjacent glass panels 12 and 14 are secured to the outward face 11 of the framing member 10 by structural adhesive beads 16 and .18, respectively. In the preferred embodiment, the structural adhesive is structural silicone adhesive. Each glass panel has dual panes, specifically, interior and exterior panes 20, 22, respectively, separated and linked as known in the art by a glass spacer 24 along the edges of the panel so as to form an air space 26 between the panes 20 and 22 for thermal insulation purposes. The silicone beads 16, 18 extend along the height of the glass panels 12, 14, to sufficiently bond the panels to the vertical framing member 10.
A retainer 28 provides mechanical retention of the adjacent glass panels 12, 14 to the framing member 10 to facilitate installation of the silicone beads 16, 18, as discussed in further detail below, and also to provide a safety feature should the silicone adhesive fail. The retainer 28 is elongate and extends lengthwise along the framing member 10. The elongate retainer 28 has a generally I-shaped transverse cross section (not including its "T"-shaped securing head 52) which forms a pair of opposing elongate channels 58, 60 (see FIG. 4), each configured to accept the edge of a corresponding glass panel 12, 14 and also to accept a corresponding spacer 40, 42.
The retainer 28 includes a generally planar base element 30 which, when installed, is urged against the outward face 11 of the vertical framing member 10. The retainer 28 also includes a generally planar foot element 32 which, when installed, contacts the exterior vertical edges 34 and 36 of the adjacent glass panels 12 and 14. The base element 30 and foot element 32 are spaced apart by a generally planar spine element 38 by a distance roughly equal to the combined thickness of the glass panel 12 and the spacer 40. It should be understood that in the preferred embodiment of the retainer in its unloaded configuration as shown in FIG. 4, the primary planar surfaces of the spine 38 are substantially perpendicular to the primary planar surfaces of the base element 30 and the foot element 32.
Referring to FIG. 4, a first preferred embodiment of the retainer according to the present invention is shown as 28.
Referring now to FIG. 3, elongate resilient spacers 40 and 42, when installed, are wedged between the base element 30 of the retainer and the interior edges 44 and 46 of the glass panels, and are positioned within the channels 58, 60 defined by the retainer. Each spacer 40, 42 in transverse cross section has a leading wedge-shaped nose to facilitate its insertion and has an interior compression void 48, 50, respectively, provided to enhance deformability. The spacers 40, 42, are elongate and coextensive with the silicone bead and the framing member, and, when in position, provide opposing forces sufficient to urge its associated glass panel outwardly and securely against the foot element 32 of the retainer. When the spacers 40, 42 are in place, they also urge the outside edges of the glass panels 12, 14, respectively, against the foot 32 of the retainer 28.
As previously discussed, the retainer 28 includes a securing head 52 extending from the center of the retainer base element 30 opposite the foot element 32. The securing head 52 has a T-shaped transverse cross section and extends lengthwise along the retainer 28. The securing head 52 is configured for engagement with a reciprocal T-shaped channel 54 defined by framing member 10. As will be discussed in further detail later in this application, T-shaped securing head 52 may slide freely within securing channel 54 when the spacers 40, 42 are not in position, such as shown in FIG. 2. However, when the spacers 40, 42 are in position as shown in FIG. 3, the securing head 52 is urged against the framing member 10 such that the frictional force between the elements 52, 10 effectively "locks" the elements together.
Installation of the overall assembly proceeds as follows. First, referring to FIG. 2, the securing head 52 of the elongate retainer 28 is slipped inside the securing channel 54 of the vertical framing member 10 and slidably positioned along the vertical framing member as desired. Then, the glass panels 12 and 14 are inserted into the U-shaped glazing channels 58 and 60 of the retainer 28, respectively, proceeding left to fight, for example. Next, now referring to FIG. 3, the spacers 40 and 42 are wedged into place between the flanges of the base 30 of the retainer 28, and the glass panels 12, 14, respectively, thereby snugging the fit of the glass panels 12 and 14 inside the glazing channels 58 and 60 (see only FIG. 4) of the retainer.
It should be understood that when the spacers are wedged into place, the glass panels are urged outwardly against the foot 32 of the retainer 28. As the foot is urged outwardly, it will exert an outward force upon the spine 38 of the retainer, therefore tending to pull outwardly on the center of the base 30. However, the spacers are likewise providing an inward force against the outer edges of the base 30. Therefore, as shown in FIG. 3, the center of the base will tend to deflect downwardly somewhat relative to the outer edges of the base, which will remain in contact with the outer surface 11 of the frame member 10. Due to the geometry of the retainer 28, spacers 40, 42 and the securing channel 54, this deflection causes the T-shaped head 52 of the retainer to come into frictional contact with the securing channel 54, thus providing frictional securement between the retainer and the frame member 10.
Finally, the structural silicone beads 16 and 18 are gunned and tooled, as known in the art, into the space behind the wedge shaped spacers 40 and 42, thereby contacting the framing member 10 and the inside vertical edges 44 and 46 of the glass panels 12 and 14. Installation across the framing system continues left to fight in a similar manner.
After the structural silicone cures, a strong structural adhesive bond is formed which provides primary support of the glass panels. However, should the silicone rupture, the retainer provides temporary support until the ruptured silicone bead can be repaired.
Referring to FIG. 6, preferably, the second preferred retainer profile 128 includes cushion pads 56, 57, preferably coextruded as an integral part of retainer 28. The cushion pads 57, hereinafter referred to as "spine" cushion pads 57, protrude from the spine 38 of the retainer 128, and serve the purpose of cushioning contact between the retainer 128 and either of the glass panels 12 and 14 beyond that afforded by the resiliency of the retainer itself. This cushioning is especially effective when one of the glass panels 12, 14, is in contact with the retainer 128, and the other of the glass panels 12, 14 is brought into contact with the retainer. Cushioning pads 56, hereinafter referred to as foot cushioning pads 56, extend from the inside of the foot 32 of the retainer 128, and contact the outside surfaces of the glass panels when installed, providing a cushioning and weatherproofing function.
Retainers 28 or 128 are each preferably coextruded profiles composed of different materials, with most of the retainer (the securing head, spine, head, and base) composed of a substantially rigid but deflectable and resilient compound polyvinyl chloride known in the art as CPVC, such as that sold under the brand name "Temprite 88997". The pads 56, 57, if used, are preferably composed of dense elastomeric material, deformable but resilient, such as that known as "ALCRYN", manufactured by Dupont. The outside surface of the foot 32 (see FIG. 5) may be provided with a coextruded layer 33 of semirigid polyvinyl chloride, treated as known in the art to be "UV resistant" (capable of resisting deterioration due to ultraviolet light exposure).
The spacers 40, 42 are preferably extruded from an elastomeric rubber material (compatible with structural silicone) being deformable but resilient.
Therefore it may be seen that the present invention provides a simple, cost-efficient, and reliable retainer assembly for effective retention and weathersealing of glass panels in structural silicone adhesive systems. The retainer assembly may be installed from the inside of the building, thus obviating the need for exterior scaffolding. The retainer assembly maintains glass panels in place during the application of structural adhesive, and also acts as a safety means should the adhesive fail. The portion of the retainer assembly viewable from the exterior of the building is unobtrusive, thus providing a desirable smooth outside appearance.
While the invention has been described in detail with particular reference to the disclosed embodiments, it is to be understood that variations and modifications may be utilized without departing from the principles and scope of the invention as defined by the following claims. | A retainer and weatherseal for structurally bonded glazing, which includes an elongate retainer profile having a generally H-shaped transverse cross section, thereby forming a pair of elongate U-shaped retaining channels; and securing device for securing the profile coextensively along a curtainwall framing member, such that one side of the pair of retaining channels is urged against the framing member. The retainer may be in combination with a curtainwall framing member, which includes a framing member having securing device longitudinally along the outward face of the framing member, for receiving the securing device and which are reciprocally configured, the retainer being secured to the framing member with the securing device interlocked in the securing device. The retainer and framing member combination are utilized in a curtainwall framing system having structurally bonded glazing wherein each of the intermediate vertical framing members of the system include the retainer and framing member. | 4 |
FIELD OF THE INVENTION
[0001] This invention encompasses embodiments for multi-modal integrated simultaneous measurement of various aspects of fluids contained in circulating systems such as automotive reciprocating engines and vehicle transmissions. These circulating systems perform constant internal lubrication, and heat and contaminant removal to protect the internal moving parts from the inherent friction and damage in normal operation. Most commonly this is achieved with fluids based on hydrocarbon and/or related synthetics, which, over time, can lose their protective properties, and vary in their performance or breakdown/decay due to internal and external events. Several components within the lubricant fluid can be measured and can provide insight into the efficacy of the system to perform its designed mission. Described herein is a real-time, simultaneous, integrated, multi-modal sensor system for early warning notification.
BACKGROUND OF THE INVENTION
[0002] This field of invention is related, but not limited to, the automobile industry. In particular, the field relates to mechanical engines and large-scale mechanical devices that utilize motile lubricating fluids operating in high temperature environments. For these lubricants, it would be beneficial to monitor in real-time the changing fluid properties, the levels of contaminants, and changes in performance to ensure safe and reliable operation of the equipment being protected by the lubricating system. This approach applies to automotive vehicles, aircraft or spacecraft, industrial equipment, wind-turbines, life-saving medical machinery and other critical devices. The conditions of fluids are often detected using a static, periodic approach, typically requiring removing fluid from the system, often by extracting a sample of the fluid to send to testing laboratories around the world, which have established procedures and methods to measure a number of aspects of the lubricating fluid, including historical time-series of various parameters. It is common practice to apply such time-based longitudinal monitoring of the fluid to detect changes over time to gain an understanding of the changes in performance within the closed environment. For example, the presence of specific particles at increasing concentrations can indicate levels of wear and performance of certain underlying components within the system being lubricated. This testing typically measures changes in characteristics of the fluid over time, including detecting changes and deterioration of underlying lubricating fluid and additives and the detection of normal (expected) and abnormal (unexpected) “wear” of the moving parts due to normal operation. Static samples are usually sent to a facility that performs a number of tests, including detecting the presence of foreign materials and objects. In some cases, such as when the lubrication fluid is changed, the lubrication filter is commonly sent as well as the oil for testing and detailed analysis. For both the sample and the filter, this is a destructive “tear down” analysis such that the filter and the sample are not returned to service, but evaluated and subsequently removed. Tests typically performed in the laboratory include detection of metallic and non-metallic particles, presence of water or other non-lubricant liquids, carbon soot and other components, and in some cases, verification that the underlying chemistry of the lubricant is still intact. A written (or electronic) report is generated and transmitted to the stakeholder upon completion of the testing. Results typically take days or weeks from extraction to stakeholder review.
[0003] A number of low-cost lubricating fluid measurement products and techniques are emerging onto the market—including a consumer static “check” of a motor oil sample (see lubricheck.com) which measures the changes in electrical impedance characteristics (electrical capacitance and resistance when a small electrical source is applied across the sensor where a sufficient sample size of the lubricant bridges the sensor electrode across to the detector). This approach performs a single-dimensional measurement of oil sump fluid properties at a point in time in the evolution of the oil (i.e. a static measurement), providing insight only when the operator manually extracts a sample of oil to be tested and only indicates changes in the electrical properties should the data be appropriately logged and tracked over time. This approach has many drawbacks including the interval sampling (only when the operator makes a measurement), as well as the potential for counteracting forces from the presence of multiple contaminants introduced into the fluid to mask the true state/condition of the lubricant. As an example, in the case of an automobile engine, the normal operation of the combustion engine will produce carbon by-products as a result of the operation of the engine (this is what discolors the oil). If a vehicle were producing only this carbon “soot” the resistance would change (increase) due to the introduction of the soot. If at the same time, the engine were undergoing adverse ‘wear’ to the extent that small metallic particles were produced as an abnormal condition across the internal moving parts, these particles would decrease the resistance, as metal is a better conductor over the base lubricant. In the case where both soot and metallic particles were being produced at the same time, they could partially or completely cancel out some or all the measurable effects—thus providing a false indication of the true condition of the lubricant and underlying engine. A testing laboratory analysis by comparison performs a number of tests which would be able to independently detect the presence of both materials in the base lubricant fluid and provide an accurate report of the condition of the fluid and the resulting system.
[0004] Lubricating fluids have to accommodate a wide range of operating conditions—including variances in temperature, pressure, purity, and state change, Lubricants are often optimized for a specific operating environment and temperature range and are expressed in viscosity. Some lubricants are designed to operate with multiple viscosities (e.g., 10 W-30 multi-grade viscosity motor oil). Typically, measurement of the fluid condition and properties is static and performed externally outside this operating environment via sampling when in a static/non-operating state. Static sampling does not necessarily validate the condition of the fluid in the operating state—either within or outside the normal/typical operating range. There are expensive and complex sensors that have been developed for measuring lubricating fluid and other liquids in real time—either for use in laboratory environments and conditions or for very high-value machinery where immediate sensor lubrication information is critical. Companies such as Voelker Sensors, Inc. offer a product for the machine tool industry that measures in real time a number of parameters including oil level, oxidation (change in pH), temperature, etc. The sensor element is not MEMS based and has a larger footprint, and is not suitable in size/form factor for operation within automobile oil/lubrication systems (“ Continuous Oil Condition Monitoring for machine Tool and Industrial Processing Equipment,” Practicing Oil Analysis (September 2003).
[0005] Outside of the field of integrated-circuit multimodal sensor systems, there have been various implementations of continuous electrical property measurements as performed by Halalay (U.S. Pat. Nos. 7,835,875, 6,922,064, 7,362,110), Freese et al., (U.S. Pat. No. 5,604,441), Ismail et al,, (U.S. Pat. No. 6,557,396), Steininger (U.S. Pat. No. 4,224,154), Marszalek (U.S. Pat. No. 6,268,737), and others which disclose either a singular vector analysis (electrical) or a time series measurement of electrical properties to derive an understanding of the oil condition. The challenge remains, as in the Lubricheck approach, to overcome the interdependent and true measurement cancelling effects that can report an incorrect oil condition. This is precisely why the fluid testing protocols and laboratories apply tests across multiple dimensions to include spectral analysis as well as tests to determine metal and other foreign object content in the oil samples.
[0006] Lubricants are designed to perform beyond their stated range and are further enhanced through the addition of “additives” to extend the lifetime and safety margin of the fluid. Understanding the lubrication longevity is crucial for the safe operation of the system. Replacement of the fluid is performed typically at very conservative (i.e. short) recommended intervals, providing a wide safety margin for the operator. In general, lubricants can operate for significantly longer intervals, or in the case of specific equipment operating in harsh environments (e.g. military equipment used on the battlefield or in mining operations, etc.) may require a more aggressive replacement cycle. It is important to determine when the lubricating fluid cannot continue to perform according to specifications determined by the equipment/system manufacturers. As long as the lubricating fluid is within the safe margin of operation, it may operate indefinitely and not need to be exchanged or replaced with fresh lubricating fluid.
[0007] Providing a more precise measure of the fluid's performance can maximize the lifetime of both the lubricant and the equipment the lubricant is protecting. As the cost of the equipment and the hydrocarbon lubricant increase, so does the value of providing both a longer and more precise lifetime of the lubricant and early detection and notification of pending equipment performance deterioration (including motor, filter, and other components in the system, etc.). This approach can potentially save lives when critical equipment failures are detected in advance. In addition, should the fluid fail and contribute to the equipment breaking down, this system potentially eliminates the resources required and time lost to repair/replace the underlying/broken equipment. This approach also avoids the loss of service and resources required to complete oil changes more often than actually needed.
SUMMARY OF THE INVENTION
[0008] In embodiments, an integrated system is provided for continuous monitoring of multiple properties of a fluid derived from measurements from a plurality of sensor modalities within a fluid-based closed-system environment. Suitably the system is an in-motor lubrication monitoring system and the monitoring is real-time.
[0009] In certain embodiments, the system is built into the form factor of a standard size and shaped oil drain plug found within a reciprocating engine oil drain pan, wherein said system is remotely located from a receiver by wired or wireless data telemetry. Suitably the system further comprises a remotely located receiver.
[0010] In other embodiments, the sensor modalities comprise at least two of electrical, temperature, magnetic, optical, pressure, and multi-axis accelerometer sensors, suitably at least one of the sensor modalities comprises an inductor. In embodiments, the sensor modalities comprise at least magnetic and optical sensors and in other embodiments the sensor modalities comprise at least electrical, magnetic and optical sensors.
[0011] In certain embodiments, the system is contained within an epoxy encapsulation that can support high temperature, high pressure, and high vibration environments contained within the oil drain plug mechanical design.
[0012] In certain embodiments, the system further comprises a limited lifetime power source that provides electrical energy to the electrical components of the sensor platform. In some embodiments, the system further comprises an energy scavenger/harvester that provides electrical power to a rechargeable power source for extended lifetime.
[0013] In certain embodiments, the system further comprises multiple digital signal processor modules for detection of both single and multiple related fluid characteristics. In embodiments, the systems further comprise multi-stage output signal generation selected from the group consisting of error indication, specific data signature detection signal, specific data signature signal detection strength level, and Fast Fourier Transform (FFT) data output.
[0014] In other embodiments, the sensor modality measurements are analyzed using Kalman Filtering techniques, Baysian analytic techniques, hidden-Markov Filtering techniques, fuzzy logic analysis techniques or neural network analysis techniques.
[0015] In exemplary embodiments, the sensor modality measurements comprise at least one of the following: differential temperature comparison, differential magnetic sensor comparison, differential inductive sensor comparison, differential electrical impedance comparison, differential optical absorption comparison, multi-axis accelerometer comparison, any combination and integrated comparison consisting of at least a set of two sensors, data comparison of each sensor vector versus time and temperature, data comparison of an integrated vector consisting of a set of at least two sensors combined, inductive data comparison versus time and temperature, optical data comparison versus time and temperature, optical data comparison versus temperature and pressure, temperature data comparison versus time and pressure to detect peak heat, pressure data comparison versus multi-axis accelerometer data, and other sensor combinations.
[0016] Also provided are methods of continuously monitoring an operating fluid of a machine comprising: measuring a first condition of the fluid using a first sensor modality, measuring a second condition of the fluid using a second sensor modality, filtering data from the sensors, integrating the data from the sensors, analyzing the data from the sensors, deriving a property of the fluid from the data, transmitting the derived property of the fluid condition to a receiver, and repeating the process so as to accumulate a time-series of a fluid property that tracks changes in the operating condition of the fluid. In embodiments, the methods further comprise tracking the condition of the fluid by calculating the time series expected rates of change versus observed rates of change of any single or multiple conditions. In additional embodiments, the methods further comprise calculating the expected divergence or convergence across multiple sensor time series data of anticipated and expected measured value changes versus unexpected changes.
[0017] Further embodiments, features, and advantages of the embodiments, as well as the structure and operation of the various embodiments, are described in detail below with reference to accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0018] FIG. 1 is a representation of an exemplary read-time multi-modal fluid sensing system described in this application.
[0019] FIG. 2 is a representation of an exemplary major in-engine sensor source and receiving elements making up the multi-modal fluid sensor solution.
[0020] FIG. 3 is a block representation of an exemplary major electronic and firmware elements of the system presented within this application.
[0021] FIG. 4 is an inset diagram of exemplary optical sensors.
[0022] FIG. 5 is a block diagram of exemplary processing electrical and/or firmware elements comprising the Digital Signal Processing modules incorporated within the processing portion of the system presented within this application for integrated multi-modal sensor calculations.
[0023] FIG. 6 is a representative framework of discrete wavelengths for the various optical properties detection.
[0024] FIG. 7 is a block representation of an exemplary power unit for the system presented in this application.
[0025] FIG. 8 is a representation of an exemplary real-time multi-modal fluid sensing system presented in this application in the exemplary form factor of a standard oil drain plug.
DETAILED DESCRIPTION OF THE INVENTION
[0026] It should be appreciated that the particular implementations shown and described herein are examples and are not intended to otherwise limit the scope of the application in any way.
[0027] The published patents, patent applications, websites, company names, and scientific literature referred to herein are hereby incorporated by reference in their entirety to the same extent as if each was specifically and individually indicated to be incorporated by reference. Any conflict between any reference cited herein and the specific teachings of this specification shall be resolved in favor of the latter. Likewise, any conflict between an art-understood definition of a word or phrase and a definition of the word or phrase as specifically taught in this specification shall be resolved in favor of the latter.
[0028] As used in this specification, the singular forms “a,” “an” and “the” specifically also encompass the plural forms of the terms to which they refer, unless the content clearly dictates otherwise. The term “about” is used herein to mean approximately, in the region of, roughly, or around. When the term “about” is used in conjunction with a numerical range, it modifies that range by extending the boundaries above and below the numerical values set forth. In general, the term “about” is used herein to modify a numerical value above and below the stated value by a variance of 20%. It should be understood that use of the term “about” also includes the specifically recited amount.
[0029] Technical and scientific terms used herein have the meaning commonly understood by one of skill in the art to which the present application pertains, unless otherwise defined. Reference is made herein to various methodologies and materials known to those of skill in the art.
[0030] To provide a more accurate understanding of a fluid, conducting multi-modal tests simultaneously can help to give insight into the true operating status and condition of the lubricating fluid. In embodiments, an integrated system is provided for continuous monitoring of multiple properties of a fluid derived from measurements from a plurality of sensor modalities within a fluid-based closed-system environment. Suitable embodiments utilize a combination of advanced Micro-Electro-Mechanical Systems (MEMS) and semiconductor techniques to place the laboratory tests directly into the fluid to continuously and concurrently measure multiple aspects of the fluid and report these parameters individually to a programmable computer to provide parallel and integrated real-time analysis of the fluid condition. As used herein the term “sensor modalities” include measurement of the magnetic, electrical and optical properties of a fluid as well as measuring the temperature and pressure of the fluid and monitoring the orientation of the fluid and surrounding containment vessel in space by measurement of multi-axis acceleration. These collectively comprise examples of “multi-modal” analysis or tests throughout the present invention. These measurements can be done both individually and combined—to provide an integrated insight into the condition and status of the fluid. As single-dimension tests may “obscure” any single result caused by the interplay between two different contaminants in the fluid (e.g. the combination of both electrical resistance increasing and electrical resistance decreasing foreign matter in the system), the application of simultaneous multi-modal sensing using a plurality (i.e., two or more) sensing modalities improves the fidelity and accuracy of the measurements.
[0031] In multi-modal sensing, measurements are combined to determine the state (and state changes) for the fluid using software/firmware programming to compare sensor inputs against reference datum and to detect changing fluid conditions across various measurement dimensions, including time. It is important to set thresholds for detection of foreign contaminants in the oil. For example, a sufficient quantity of water over time can cause corrosion of critical elements normally protected by the lubricating fluid. Based on these thresholds, certain alerts and notices can be provided, either transmitted through an output interface or polled by a wireless interface, optionally using a portable hand-held device, such as a smart phone. To validate the ongoing assessment of the fluid condition, a secondary check can be done to verify the measurements through periodic laboratory sampling. External validation can be part of the conforming calibration process during initial testing of the multi-modal sensors. External validation can also qualify additional lubricating fluids and operating environments. Once the baseline is understood, the thresholds across all the integrated measurements can be programmed into the semiconductor to provide the alerting functionality over and beyond the integrated measurement data outputs.
[0032] In additional embodiments, the systems and methods described herein detect use of the wrong fluid or unsuitable lubricating fluid that may be mistakenly introduced into the lubrication system. Operating machinery with the wrong lubricating fluid can cause irreparable harm if not immediately remediated. The multi-modal sensor ‘expects’ lubricating fluid to be conforming, raising an alert when non-conforming fluid is introduced and subsequently detected.
[0033] Specific individual sensors can be combined into a framework that provides a much more complete understanding of the state of the system, both for immediate measurement as well as longitudinal monitoring. Such sensor frameworks greatly improve real-time monitoring of system conditions and greatly improve the ability of the system to automatically recognize and respond to a variety of operational events.
[0034] In particular, frameworks incorporating magnetic sensors facilitate the timely recognition of ferrous metal contaminants. For example, paramagnetic resonance can characterize the nature of the ferrous particles, and potentially their size.
[0035] Integrating optical transmissometers, opacity measurements or spectral measurements into the framework provides an indication of particular contaminants, for example, soot, water, or antifreeze solution. Further the invention can be improved through the incorporation of multi-modal sensing analysis to include for example pressure and temperature that may change the optical properties of the fluid. These correcting factors can be applied to improve the accuracy of the measurements.
[0036] Integrating electrical measurements into the framework provides a more complete picture of the fluid condition. These measurements can also detect and can provide independent ways to distinguish between alternative fluid status and condition diagnoses. This state change is detectable by a set of at least one of the sensor modalities.
[0037] A control system integrates disparate sensors, utilizing patterns of sensor conditions to “recognize” or “diagnose” sets of conditions worthy of further attention. Established mathematical algorithms for such analysis include and are not limited to Kalman filtering (and enhanced Kalman filtering), hidden-Markov models, Bayesian analysis, artificial neural networks or fuzzy logic. These control systems can be implemented readily in software, firmware or hardware, or a combination thereof (See: “ Solutions for MEMS Sensor Fusion ,” Esfandyari, J, De Nuccio, R, Xu, G., Solid State Technology, July 2011, p. 18-21; the disclosure of which is incorporated by reference herein in its entirety)
[0038] In further embodiments, additional understanding of the fluid properties under different machinery operating conditions can be gained, for example, including “at rest” when the system is not operating, or at “peak heat,” which may actually occur after the system shutdown. Temperatures may increase after shutdown when no cooling fluid is circulating. Fluid properties will change as the fluid heats and cools. Measuring these changes across the short heating or cooling interval can yield valuable additional indications and insights into the properties of the lubricating fluid. For example, optical absorption may vary as the fluid heats. In addition, tracking the change in electrical properties with temperature can provide further information as to the condition of the fluid. Deviations may cause the control system to request measurements not only when the machinery is operating but also upon startup or shutdown, for example.
[0039] The present application overcomes a number of limitations of traditional diagnostics. First, the traditional time delay from fluid sampling to testing may place critical equipment at risk of damage. Sometimes the lubricating fluid is sampled at the time it is being exchanged. While potentially useful for providing insight into the wear of internal parts, machinery may be operated in a potentially unsafe condition until the results are returned from the laboratory. Second, the lubricating fluid may be exposed to extreme temperatures during operating transients, which can be often in excess of 150 degrees C., potentially causing some breakdown of additives in the lubricating fluid. Such problems are not usually detected, as the equipment often is “turned off” during these conditions. Although there is no new heat being generated, residual heat is transferred into the lubricating fluid and can potentially impact its performance. Such temperature extremes often require special engineering effort to design integrated in-situ sensing systems to support reliable operation (e.g. from −50 C to +150 C). Further, sensors and other electrically active elements need to support this environment. Equally important is the support of various pressures that the lubricating fluid may experience during normal and high-load operations. An in-situ sensor framework must be designed to withstand the peak temperatures and pressures experienced within the lubrication system over time.
[0040] Several variables provide insight into lubrication fluid properties. Some variables can be measured directly while others can be derived. To achieve a basic understanding of fluid condition, several measurements (sensor modalities) of the lubricant may be helpful, including, for example, temperature, absolute pressure, electrical impedance or resistance, pH, optical transmission or absorption, and magnetic measurements. Measurements are either direct (e.g. temperature via a temperature sensor) or derived—such as degree of carbon buildup via combined measurement of electrical and optical changes. Standard techniques are available and used today such as thermocouples and pressure sensors to acquire some of these data points. Derived measurements (e.g. viscosity conformance within operating range) can be calculated from direct measurements, and can be extrapolated over ranges of temperature and pressure. Additional detection methods include the use of one or more inductive coils and magnetic sensors to enhance detection of moving metallic particles. An optical transmissometer, comprised of an optical light source and optical detector, for example, measures the changes in absorption of optical light at various wavelengths to characterize carbon soot buildup and other potential contaminants and materials in the lubricating fluid. All such measurements should be temperature and pressure compensated (or normalized) to provide an accurate indication of the underlying health of the lubricating fluid. Further, pressure measurements can be qualified for changes in the system orientation. Computation of orientation from multi-axis accelerometers is used to determine when a pressure reading may be invalid due to the system being oriented beyond a predetermined standard, or alternatively the pressure reading is compensated for a system orientation within predetermined limits of such a standard.
[0041] Viscosity analysis derives a frictional index from multiple sensor readings to determine the net fluidic friction of the lubricant. This invention presents a simple method of deriving viscosity by measuring, for example, two magnetic sensors within the fluidic lubricant in a selected site to measure fluid flow. These magnetic sensors, such as no-latency Hall sensors, are substantially similar and located in close proximity to one another within the lubricant flow. A small turbulence inducer enables measurement near the sensors of slight differences in flow based on induced flow perturbation. This measure can be further integrated with optical absorption measurements using the optical transmissometer. This integrated measure, coupled with temperature or qualified pressure readings, provides a framework for calculating the frictional index. The Hall-based sensors are designed to be as similar as possible. Temporal and spatial variations not caused by the turbulence inducer are subtracted using the two nearly identical sensors. Further, the shape of the turbulence inducer is designed to create subtle changes related to the fluidic velocity, analogous to aeronautical applications in which fluid molecules travel at slightly different speeds above and below an airfoil. Viscosity can be derived from these slight difference measurements along with the local temperature and pressure, using documented lubricant viscosity reference data, providing an indication of real-time lubricant conditions.
[0042] Sensors are suitably designed to withstand high temperatures of the engine lubricant. High-temperature thermocouples measure temperature, thick-film resistors enable pressure sensing, and high-temperature magnetic sensors. The optical measuring methods are based on proven high-temperature designs. The optical spectrum suitably ranges from UV to mid-IR in which the lubricating fluid is not emitting energy at high temperature, depending on the fluid and the environment and potential contaminants. The transmissometer range is measured in millimeters and the distance between the emitting element and the receiving element is precisely controlled using known MEMS manufacturing techniques. This distance between the optical emitting and receiving elements must be very accurate. All of these elements have been implemented and operate individually within these extreme temperature and pressure environment in such a manner as to relay useful data. The design is not limited to these methods. At present, these methods are proven effective and provide a simple solution.
[0043] In embodiments, the systems and methods described throughout provide real-time monitoring of fluids such as those associated with high-temperature environments present within or associated with internal combustion engines (i.e., monitoring the fluid during engine activity without the delay of removing a sample). Suitably, the systems and methods monitor oil-based fluid lubricants normally used with internal combustion engines, as well as other fluids such as transmission fluids or glycol-based coolants such as antifreeze, and other fluids in manufacturing environments and critical life-saving medical equipment used in the healthcare industry. The systems and methods suitably provide real-time monitoring using multiple sensor modalities to determine the degradation of the monitored fluid under various operating conditions. Another aspect is the ability of the invention to detect the presence of known harmful particulates, such as metal, within the lubricant. Another aspect addressed is monitoring fluid with a sensor module that is continually submerged within the lubrication fluid. Another aspect addressed is the parallel and integrated real-time analysis of the fluid condition. This invention also addresses high temperatures and other conditions experienced in the operating environment of such machinery.
[0044] In exemplary embodiments a real time multi-modal fluid sensing system is in a self-contained embodiment of a single unit comprising an active sensing environment ( 100 ) intended to be submerged in the fluid to be monitored. The sensors are attached to an assembly that can be placed into the fluid with the electronic and active sensors embedded into a oil drain plug ( 300 ) that is held in place via a threaded bolt ( 200 ). The bolt head accommodates the non-sensor elements of the self-contained system, called the command, control and communications module, C3 module ( 400 ) to include the microcontroller, filters and other elements. Also suitably contained within the assembly are inductor coils ( 108 ) and other methods of signal source to include power to operate the system, such as a power source ( 180 ). The bolt assembly is a self-contained platform that can be installed and removed by a technician. Such an environment is typical of an oil drain plug on an automobile or a similar “low point” in a lubricating return system that may also serve as a reservoir for the fluid. The fluid environment may be subject to changes in temperature and pressure through normal and abnormal operations. As such the sensors are designed to operate within the temperature and pressure specifications—as well as customary tolerances beyond the normal operating environment to be able to detect abnormal conditions.
[0045] Within the sensing environment the system programmatically generates its own local and low energy reference signal sources across multiple sensor modalities including magnetic, optical and electrical, and continuously detects values therein as well as passively receives continuous pressure and temperature measurements. The active elements of the sensor platform ( 100 ) are intended to be submerged in the fluid under measurement. In the case that the sensor is not submersed, either completely or partially into the fluid, this can be detected and confirmed through multiple sensor confirmation across the optical ( 106 ) transmission to optical reception ( 107 ) as well as electrical source ( 101 ) to reception ( 104 ) of expected value tolerances. In this way the condition of lack of fluid can be detected by multiple approaches, as well as verify that both the electrical and optical sensors are correctly and collaboratively cross-checked.
[0046] Magnetic sensing is achieved through generating a signal of a pre-defined and programmable characteristic ( 102 ) that has a known fixed reference distance within close proximity to the magnetic sensors ( 103 ) that is received and processed by a data acquisition control unit ( 109 ) that performs signal amplification, A/D conversion and data filtering. The sensing can be accomplished by one or more sensors ( 103 ) of a type such that provide a response rate commensurate with the signal, that can be the same type or different and provide both direct and differential measurements of the fluid condition. The data acquisition control unit ( 109 ) performs the steps to filter and analyze the signals, including amplification, noise reduction filtering which is then communicated to the microcontroller ( 140 ).
[0047] One or more optical sensors ( 107 ) can be coupled to one or more optical source(s) ( 106 ) which can consist of one or more specific optical wavelength emitters such as narrow frequency tuned light emitting diodes (LEDs) and optical receivers such as photoreceptors. Today's optical emitters can be configured to emit light in narrow frequency bands. Such wavelengths are dependent upon the specific types of fluid and contaminants that may accumulate within the fluid. FIG. 6 shows a representative map over the near infrared region of such. The optical sensing can determine a number of characteristics, including but not limited to the presence of fluid, when the LED is emitting. Further the LEDs can be placed at different known and fixed distances from accompanying photoreceptors to provide a distance based profile of the level of absorption across different frequencies. The embodiment can be accomplished by a single LED emitter to photoreceptors at known distances as well as multiple LEDs spaced at known distances from the photoreceptor pulsed in a known sequence. The controlling logic is managed through software/firmware in the microcontroller ( 140 ) and in the data acquisition control unit ( 109 ). Optical sensing can detect the difference in both the specific wavelength absorption and time series changes in optical characteristics. The optical sensing developed operates in both an active and passive mode. In the active mode the optical source pulses light of known strength and wavelengths through the fluid to measure the degree and level of absorption of the light from its source. This small scale transmissometer is configured to detect the specific contaminants and/or changes such as a breakdown in the fluid properties across specific wavelengths, such as shown in FIG. 6 .
[0048] Sensing changes in the electrical properties is accomplished by an electric source ( 101 ) placed at known reference distance from an electric capacitive measuring such as the constant of dielectric of the fluid. The strength and frequency of signal and measurement is based on the programmable microcontroller firmware and is based and dependent on the underlying characteristics of the fluid to be continuously monitored which lies between the source and measurement sensing. The electric resistance and capacitance can be measured across the gap via the data acquisition control unit ( 109 ). Different fluids will have different properties, and thus the ability to programmatically configure and control both the source field and sensor receiving properties is an important aspect of this invention. Pressure sensing ( 111 ) and temperature sensing ( 110 ) are also connected to the data acquisition control unit ( 109 ). These sensors can also detect normal and abnormal conditions in heat and pressure levels and provide insight to the operating status of the environment. Fluid condition changes—such as at rest (when the system is not operating) through the peak operating environment—can be evaluated by the programmable microcontroller unit ( 140 ). Such applications can be developed in software/firmware to include developing an understanding of both “at rest” and “in operating” conditions. Further, the profile at specific pressures and temperatures can be useful for both determining calculations (offsets due to temperature/pressure—such as if magnetic sensors are based on using the Hall Effect ( 103 )) as well as optical property changes due to temperature and pressure profiles.
[0049] Tracking changes in the orientation of the oil drain plug ( 300 ) of FIG. 1 in three-dimensional space is accomplished by multi-axis accelerometer sensors ( 112 ). Note that in alternative embodiments, accelerometer 112 may be disposed in the C3 module ( 400 ), MEMS sensor platform ( 100 ), receiver ( 170 ), or other external location. The accelerometer sensor ( 112 ) may be disposed in the MEMS device ( 100 ), in the non sensor elements of the self contained system, called the command, control and communications module, C3 module ( 400 ), or near another processor unit. The acceleration of each axis of interest is measured by the data acquisition control unit ( 109 ) and used to compute the orientation of the oil drain plug ( 300 ), and therefore the orientation of the engine and of the vehicle in space. The orientation computation can be used by the data acquisition control unit ( 109 ) to qualify the measurements from the pressure sensors ( 111 ) and reject certain pressure readings or make adjustment to certain pressure readings to compensate the pressure output, according to predetermined standards of orientation.
[0050] A real time clock ( 150 ) provides an accurate time basis to trigger monitoring events by the microcontroller module ( 140 ) and associate acquired data with a time basis for longitudinal analysis. The real time clock provides both time and date information that can be associated with each of the recorded multi-modal sensor measurements.
[0051] The programmable microcontroller ( 140 ) also provides both pre and post processing of information including the use of filtering and other algorithms to provide data correction. The results are communicated via a communications module ( 160 ) either via a wired or wireless connection to a receiver ( 170 ). Note that receiver 170 may optionally comprise a display, a processing unit, or both, receiving data from the integrated system. Both the receiver ( 170 ) and the microcontroller may possess internal storage ( 280 ) to record and evaluate time-series data.
[0052] Within the microcontroller ( 140 ) sensor data is accumulated and subject to additional filtering and integration across the multiple sensors. The raw data is subject to processing by a set of at least one digital signal processor (DSP) for each of the individual sensor modalities such as temperature, pressure, optical absorption, electrical impedance and magnetic signature ( 203 , 204 , 205 206 , 207 and 208 ). A parallel output of the results—both pre and post data correction filtering ( 220 ) provides both a raw data output ( 260 ) that can be communicated via a communications module ( 160 ).
[0053] A configuration module ( 270 ) can dynamically set filtering and processing parameters to the enhanced filtering ( 220 ) to include baseline and error conditions as well as other parameters including configuring storage, event monitoring, triggers, etc. The configuration module is connected via the communications module ( 160 ) to an external device.
[0054] Further, during operation that can be either continuous or polled at intervals as directed by the microprocessor and associated programming software, and further enhanced by the inclusion of a real time clock to provide an accurate time basis ( 150 ). Such measurement “cross checking” provides for both inherent value confirmation, improves that data correction (by example Kalman filtering and other algorithmic techniques) and overall sensor system integrity. For many high value systems when a “fault” is detected, often the failure is not in the environment, but the sensor. This invention provides for the cross-correlation and verification of the inherent sensor platform by continuously validating across a number of the measurement criteria such that expected and anticipated sensor output/values can continuously validate the sensor system performance. In this way the isolation of the error condition (e.g. the sensor failure) is in itself a valuable operator insight—to identify and replace a faulty sensor as a known failed device.
[0055] A power source ( 180 ), comprising electrical storage ( 182 ) and an optional energy harvester, provides electrical power to the C3 module ( 400 ) and sensor platform ( 100 ). In one embodiment, the electrical storage comprises a battery that provides power to the system until it is discharged. In another embodiment, the electrical storage comprises a rechargeable battery connected to one or more energy harvesters, which extend the lifetime of the electrical storage beyond a single charge. In another embodiment, the power storage comprises an electrical double layer capacitor, optionally coupled to an energy harvester that extends the lifetime of the electrical storage beyond a single charge.
[0056] In one embodiment, the energy harvester comprises a vibration energy harvester ( 183 ) that converts kinetic energy from the environment into an electrical current. In another embodiment, the energy harvester comprises an acoustic energy harvester ( 184 ) that converts audible or vibrational energy into an electrical current. In another embodiment the energy harvester comprises a thermal energy harvester ( 185 ) that converts differential temperatures into an electrical current. In another embodiment the energy harvester comprises an electromagnetic energy harvester ( 186 ), where an antenna ( 188 ) collects background electromagnetic radiation, such as RF transmissions, for conversion into an electrical current.
[0057] The C3 module ( 400 ) communicates with the Receiver ( 170 ) using either wired or wireless protocols, or both. Suitable protocols exist in automotive systems today, such as Controller Area Network bus (CAN) and Local Interconnect Network bus (LIN) for wired communications, and Tire Pressure Monitoring System (TPMS) and Remote Keyless System (RKS) for wireless communications. The Receiver ( 170 ) in some embodiments could comprise a processing unit. It could also comprise a display for depiction of the monitoring status.
[0058] The mechanical design for sensing changes in fluid parameters in-situ incorporates unique features to minimize costs and provide an environmentally sound design for long life. The concept is to include a pressure sensor device built into the oil drain plug that allows for simple installation for upgrades and replacement on scheduled maintenance schedules. The sensor is mounted with an epoxy polymer resin that has an excellent operating temperature range, adherence properties, and resistance to salts and petroleum by products. This is a key to prevent issues with differential thermal expansion, delamination, and chemical breakdown. The bolt has a standard thread size based on the end users specification. A hole is drilled through the middle of the bolt to allow for installation of the integrated system and to provide a path for the oil to reside over the sensor platform ( 100 ). The outside of the pressure sensor is open to the atmosphere via an integrated atmospheric pressure pipe ( 314 ). The head of the bolt is machined down to fit the sensor into the bolt by creating a cavity.
[0059] FIG. 7 depicts a power source comprising energy storage ( 182 ) and/or an energy harvester ( 183 - 186 ) for adding to the energy storage ( 182 ). Such energy harvesters could collect vibrational energy ( 183 ), especially from the oil pan of an operating engine, or acoustic energy ( 184 ). Many embodiments also comprise a thermal gradient between fluid pan and the environment, in which harvester ( 185 ) could comprise a TEC (Thermo-Electric Converter) for the conversion of thermal to electric energy, as is known to those of skill in the art. Alternatively, Electromagnetic Harvester ( 186 ) could collect energy from any one of electric field, magnetic field, inductive, wired or wireless electromagnetic energy, optionally using antenna ( 188 ).
[0060] FIG. 8 depicts an overall cutaway view of the oil drain plug multi-modal sensor system, showing one particularly favorable embodiment of the present invention, including C3 module ( 400 ), integrated MEMS sensor platform ( 316 , equivalent to sensor platform 100 ), and battery ( 180 ), RF antenna ( 310 ) provides communications and in some embodiments performs the energy havesting of antenna ( 188 ). Printed circuit boards ( 312 ) shown in cutaway view provide one or more substrates and electrical coupling for C3 module ( 400 ) and MEMS sensor platform ( 316 or 100 ). Ambient pressure pipe ( 314 ) conveys the ambient pressure to a differential pressure sensor disposed in this embodiment on sensor platform ( 316 ). Note that other embodiments could use an absolute pressure sensor in place of this differential sensor, with or without an additional ambient pressure sensor to enable an electrical compensation as opposed to mechanical pressure compensation. Temperature compensation is also known to those of skill in the art for these pressure sensors to improve accuracy and repeatability. Bolt threads ( 200 ) provide a conformal drop-in replacement for a traditional oil drain pan bolt in some preferred embodiments.
[0061] In one embodiment, this sensor system measures the pressure near the bottom of the fluid reservoir, and optionally compares this pressure to ambient pressure. Optionally temperature compensation may be included for this measurement. This approach can measure the mass of fluid in a column above the sensor corresponding to the static pressure in a gravitational (or accelerational) field. For a given temperature, this static pressure approximates the level of the fluid at a particular temperature and orientation of the fluid-containing vessel.
[0062] The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. The illustrative discussions above, however, are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to explain the principles of the invention and its practical applications, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. | This invention encompasses embodiments for multi-modal integrated simultaneous measurement of various aspects of fluids contained in circulating systems such as automotive reciprocating engines and vehicle transmissions. These circulating systems perform constant internal lubrication, and heat and contaminant removal to protect the internal moving parts from the inherent friction and damage in normal operation. Most commonly this is achieved with fluids based on hydrocarbon and/or related synthetics, which, over time, can lose their protective properties, and vary in their performance or breakdown/decay due to internal and external events. Several components within the lubricant fluid can be measured and can provide insight into the efficacy of the system to perform its designed mission. The mass and level of the fluid may also be monitored on an on-going basis. Described herein is a real-time, simultaneous, integrated, multi-modal sensor system for early warning notification. | 5 |
This application is a continuation-in-part of application Ser. No. 08/111,189 filed Aug. 24, 1993, which is a continuation of application Ser. No. 07/894,084 filed Jun. 5, 1992, abandoned.
BACKGROUND OF THE INVENTION
This invention pertains to a method and apparatus for applying resilient surfaces to be used for running tracks, tennis courts, playgrounds, jogging paths, ballfield warning tracks and other activity areas requiring resilience.
Many materials and methods of application have been used to produce all-weather surfaces for the aforementioned uses, including pre-manufactured and in situ types. These systems typically involve a mixture of rubber granules, which provide resilience and traction, and a liquid binder, which hardens or cures and thereby holds the rubber particles in a solid matrix.
Pre-manufactured products are expensive and difficult to install. Indeed, the installation of pre-manufactured products inevitably results in many seams or joints which can fail in outdoor use. Accordingly, most installations of all-weather surfaces have been of the in situ (formed on site) type. Currently, there are two basic methods of in situ installation, commonly referred to as "dry" and "wet" applied.
The wet application process involves mixing rubber particulate with liquid binder in a mixer at specific ratios and batch sizes (usually at a ratio, by weight, of 60% binder, 40% rubber). The resulting slurry is spread onto the area to be surfaced by hand or mechanical means. This application is usually done in multiple layers when using latex binder and in one mechanically paved layer when using urethane binders. With respect to the latter, the application is typically accomplished by means of a track driven paving machine with an oscillating oil heated screed. This installation method creates paving joints or seams approximately every eight feet, as well as transverse joints approximately every 100 to 200 feet. These joints are not only aesthetically objectionable, they also create weak links in the system which are subject to premature failure. To cover these joints and seams, multiple structural sprays are usually applied to paved base mat polyurethanes. However, this method is limited to a maximum particle size of approximately 2 mm, and requires a high ratio of binder. Attempts have been made to use this method with latex binders, however there is a tendency for the rubber to separate from the liquid and clog the hose. Moreover, even with latex binders the particle size is limited to a maximum of 2 mm. With rubber particle sizes larger than 2 mm, the velocity of the rubber exiting the tip of the spray nozzle was such that the rubber "bounced" when impacting the substrate, thereby separating the rubber from the liquid binder. Moreover, such small particle sizes means that surface thickness cannot be built up to typically required depths without intolerable cost in terms of time and materials, and without un acceptable loss of resilience and porosity in the resulting surface. Stated differently, one could spray apply a track surface to typical thickness (3/8 or 1/2") using rubber particles of less than 2 mm, but such a process would not be economically feasible. Hence, this method is inappropriate for surfaces with greater than 2 mm in depth because of the man-hours required for application of thicker surfaces. In addition, the rubber and binder are mixed in a hopper, and unless conveyed to the site of application promptly, may set prematurely either in the hopper, the hose, or the spray nozzle.
The structural spray coats are the standard method of adding color to this type of track surface. Structural spray coats consist of 0.5 to 1.5 mm EPDM rubber, polyurethane binder and color pigmentations. However, this surface traditionally shows premature shadowing (signs of "black through"). This shadowing occurs because the structural spray can only be applied in limited thicknesses or it will choke the surface creating problems of adhesion and delamination. Thus, these structural sprays are generally applied to a maximum of 2 mm thickness with 0.5 to 1.5 mm rubber.
Conventionally the most common method for applying latex tracks is called the "rake and spray" or "dry" method. This process involves simply evenly raking out a layer of dry rubber granules onto the track base and then spraying over the granulate with a latex binder. This process is repeated with successive layers of rubber until a desired thickness is reached.
Although this method provides a more affordable athletic surface than polyurethane surfaces, is seamless, and does not require heavy investment in equipment, it is flawed in several major respects:
1. The method depends totally on the applicator to assume that a uniform ratio of rubber to binder is maintained. This is extremely difficult, since it requires the applicators to spread rubber by hand at the same poundage per unit area at all points on the surface, and then requires that the sprayer of the liquid binder applies exactly the same volume of liquid to each unit area. Improper application renders surfaces installed by this method prone to inconsistent results which are manifested in weak or easily abraded areas of the surface.
2. The method relies on migration by gravity of the liquid binder through the rubber granules in order to accomplish encapsulation of all the rubber particles. The ability or extent of migration can vary significantly, however, with the poundage of rubber applied per unit area and with the sizing or gradation of the rubber. For example, the presence of more fines will greatly inhibit migration. Since the recycled ground rubbers used in a running track surface vary dramatically from load to load or even from bag to bag, migration and therefore encapsulation can vary greatly.
3. Latex binder does not have the same physical properties as polyurethane binder. Its resilience is more effected by temperature, which means the majority of latex track surfaces are very hard during track season (February through mid May). In addition, latex binder is very susceptible to moisture during curing, which causes unraveling and delamination.
This "rake and spray" method of the prior art tends to pack the rubber tightly, which means more rubber and therefore more binder is necessary for a given thickness.
The wet and dry methods of application each have the further disadvantage of being labor intensive and time consuming.
In view of the added difficulties associated with the dry application method, various attempts have been made to devise continuous wet application methods rather than batch for both latex and urethane binder systems.
SUMMARY OF THE INVENTION
The problems of the prior art have been solved by the instant invention, which provides a method and apparatus for coating particulate material such as rubber with liquid binder and applying the same to a substrate in a continuous mix operation without the need to mix individual batches of rubber and binder. Total encapsulation of the rubber particulate with the liquid binder is accomplished prior to applying the mix to the substrate. In addition, the method of delivery of the rubber and binder maintains the ratios thereof uniform; thus, the system is not prone to mechanical problems such as clogging.
In its method aspects, the instant invention involves separately introducing a stream of particulate and a stream of binder into a spray nozzle, where they are combined and delivered to the substrate.
The apparatus of the instant invention includes a nozzle assembly having a central lumen and an elongated tip, the lumen being formed so as to force the rubber particulate introduced therein to follow a circuitous or indirect path therethrough and thereby decrease its velocity prior to being ejected from the nozzle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial diagrammatic view of the apparatus used in accordance with the present invention;
FIG. 2 is a side view of the nozzle assembly used in accordance with the present invention; and
FIG. 3 is a cross-sectional view of the dispersing ring of the nozzle assembly along lines A--A of FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
One suitable rubber utilized in the instant invention is a terpolymer elastomer made from ethylene-propylene diene monomer (referred to hereinafter as "EPDM"), typically used when colored surfaces are desired. It will be understood by those skilled in the art that any suitable rubber or resilient particulate can be used, depending on the application. For example, other particulate material suitable for use in the present invention includes ground tire rubber (SBR) and resilient plastics. Where multiple layers are applied, each layer need not be comprised of the same particulate material.
The binder system also depends on the application, and can be any liquid system capable of forming a bond with the particulate, such as an asphalt emulsion, urethane system, latex system, or any combination thereof. For example, suitable binders include carboxylated styrene butadiene latex, styrene-acrylic copolymer latex, acrylic latex, vinyl acrylic latex, water-borne urethane (aromatic and aliphatic), diphenylmethane diisocyanate-urethane (MDI), and toluene diisocyanate (TDI). Suitable surfaces which are a combination of particulate and binder are exemplified by those commercially available from Sprintrax under the Sprint 200®EA (a carboxylated styrene butadiene latex based surface), Sprint 200®E, Sprint 200® (an acrylic co-polymer based surface), Sprint 300™ (MDI) and Sprint 400™, Sprint 2000 Supreme (water-borne urethane) and Sprintcote series.
The surface to be constructed in accordance with the present invention is typically applied to an existing asphalt or concrete base.
Turning now to FIG. 1, there is shown apparatus to be used in accordance with the instant invention. The apparatus is a modification of conventional equipment typically used for the application of GUNITE, such as the GRH 600 Rotary Gun commercially available from Allentown Pneumatic Gun, Inc.
Liquid binder is stored in holding tank 10 of suitable size. Suitable liquid binder feed hose, such as 3/4" I.D. rubber hose 12 is connected to tank 10 and is in communication with the nozzle 30 (FIG. 2). Pump 14, which can be any suitable type typically available for the purpose of pumping the type of liquid binder being used, such as an air actuated or motor driven pump, is attached to the hose 12 and produces sufficient pressure to convey the liquid binder to the nozzle 30. In the case of an air actuated pump, a compressor 16 of suitable capacity (185 cfm as been found to be appropriate) and an air line 18 associated therewith and with the pump 14 is used.
The compressor 16 also can be used to drive and provide transport air for the rotary gun/hopper assembly 20. The hopper 22 is of suitable capacity to hold sufficient rubber particulate, preferably in excess of 250 pounds of rubber particulate. The hopper 22 preferably includes a bag breaker, as the rubber material is typically packaged in a paper bag. A spider 24 comprising a vertical rod (not shown) with small horizontal or angled arms 47 projecting into the hopper chamber is attached perpendicular to the feed hole 48 and is caused to rotate within the hopper 22 by a rotor 26 driven by motor 29 in the rotary gun. Operation of the spider 24 helps prevent bridging, blocking and/or agglomeration of the rubber in the hopper 22 and breaks up any agglomerations of particulate than may have formed. The spider 24 also helps in continuously feeding the rubber particulate through a rotating manifold or rotor 26 which distributes the particulate evenly into an air stream. The air stream may be produced by any suitable means, such as by a blower or air compressor. Where an air compressor is used, it can be the same compressor used to actuate air pump 14. The particulate is transported by the air stream through a hose 28 to the nozzle 30. A hose having an internal diameter of 1.25 inches has been found to be suitable for transporting the rubber particulate in the air stream to the nozzle 30.
Turning now to FIG. 2, there is shown a nozzle 30 which includes a conduit portion 45 and a nozzle head 32 at a distal end of the conduit portion 45, the head 32 being positioned at about a 45° angle with respect to the conduit portion. A suitable internal diameter of the conduit portion 45 is 1.25 inches. A dispersing ring 34 (best seen in FIG. 3) is located at the proximal end of the nozzle 30. A plurality of circumferential orifices 36a-36n are formed in the dispersing ring 34, with eight evenly spaced orifices each having a diameter of 1/4" being preferred, although it should be understood by those skilled in the art that the size and number of the orifices depends on the viscosity of the liquid binder being used. The hose 28 is coupled to the proximal end of the nozzle 30, and the air stream conveying the rubber is introduced into the nozzle 30 and flows through the central lumen 38 of the dispersing ring 34. The liquid binder is pumped via feed hose 12 into the circular chamber 40 housing the dispersing ring 34 (FIG. 3). Pressure developed by the pump 14 forces the liquid binder through orifices 36a-36n in the dispersing ring 34, causing the binder to enter into the air stream carrying the rubber particulate. As the air stream carrying the particulate and binder flows toward the distal end of the nozzle 30, the binder becomes uniformly dispersed in the air stream and ultimately the particulate becomes encapsulated by the binder.
Other means of introducing the binder into the rubber include the use of multiple spray heads (not shown) through which the binder is sprayed into the air stream carrying the rubber.
In order to reduce the velocity of the binder-coated rubber particulate exiting the nozzle head 32, and thereby reduce or prevent the particulate from bouncing when it impacts the substrate, the length of the nozzle 30 between the dispersing ring 34 and the end of the nozzle head 32 should exceed twelve inches. Preferably the length of the nozzle 30 is about 20 to about 32 inches long, most preferably at least about 24 inches long. The elongated nozzle 30 also results in additional contact and wetting of the particulate with the liquid binder, which in turn causes further encapsulation of the rubber particulate by the binder. In addition, in order to create a circuitous or indirect flow path as the air stream travels from the dispersing ring 34 to the nozzle head 32, crimps or pinches 42a-42n are formed in the wall of the nozzle 30 at various intervals along its length (three shown), which cause the particulate to bounce against the inner walls of the nozzle 30 and decelerate. In the embodiment where the conduit portion is 1.25 inches in diameter, crimps which extend 1/2" into the central lumen of the nozzle 30 defined by the conduit portion 45 have been found to be suitable.
The ratio of binder to rubber particulate can be regulated as desired by any suitable means, such as by increasing or decreasing the rate at which particulate is fed from the hopper 22 by increasing or decreasing the rotation speed of the feed manifold and spider. In addition, the rate of flow of the liquid binder can be regulated by any suitable means, such as by a ball or needle valve 44 located just before the proximal end of the nozzle 30. By properly setting these flow rates, the operator can spray a specified mixture of rubber and binder onto a substrate in a continuous fashion. Depending upon the curing characteristics of the binder being used, a surface can be applied by this method in one, two or more passes. Since the flow of liquid and rubber can be independently controlled, the ratio of rubber and binder therefore can be controlled at a constant rate. Those skilled in the art will recognize that the ratio of binder to rubber desired depends upon the desired characteristics of the surface. For latex-based surfaces, the preferred ratio is about 40% latex and 60% rubber. For urethane-based surfaces, the preferred ratio is about 22% urethane and about 78% rubber.
The regulation of each stream also allows other methods of application with the same machinery. For example, after the surface mat has been installed, it can be over-sprayed with binder alone (i.e., no rubber particulate) by simply turning off the particulate material feed mechanism. For example, a urethane overspray of about 1 lb/yard can be applied for added strength. Similarly, a surface could be installed by spraying binder with no rubber and then blowing rubber with no (or a small proportion of) binder into the wet or uncured binder, allowing each course to cure, and then repeating the process until enough courses are applied to achieve the desired thickness.
The instant method and apparatus also is not limited to any specific size of rubber particulate. This is so because the rubber particulate passes through the central lumen of the dispersing ring 34, not through small orifices. Only the liquid binder flows through small orifices. In addition, the particular rheology of the liquid is not critical to the transport of the rubber particulate, since the binder and particulate are transported to the nozzle 30 separately. Suitable particulate material has average particulate diameters ranging from about 0.5 to about 7 mm. More specifically, particulate material having average diameters in the range of 0.5-1.5 mm, 1-3 mm, 1-4 mm, 1-5 mm, 2-6 mm and 4-7 mm have all been found to be functional. In view of the relatively large particle diameter that can be used in the present invention, the required surface thickness can be achieved with a minimal number of layers (2 to 5) and with sufficient void ratios to allow for much greater yield of materials and significant improvements in resilience and porosity.
Since the binder and rubber particulate are not combined until the separate streams reach the nozzle, premature curing is eliminated. Since the rubber particulate in the hopper is not mixed with the binder therein, it can be stored in the hopper 22 without problematic premature curing.
An added benefit of the present invention is the ability to build surface thickness with lower density of rubber. The "rake and spray" method of the prior art tends to pack the rubber more tightly, which means more rubber and therefore more binder is necessary for a given thickness (about 15% more). Not only does a less dense mat yield greater resilience in the surface, it also reduces the cost of materials.
In a preferred embodiment of the present invention wherein urethane is the binder, in order to obtain a smoother surface, the surface is bullfloated after each layer is applied. Best results are obtained when the bullfloating is carried out within about 0.5 hours after spray application. The system can be successfully installed by bullfloating the last layer of rubber applied, the last two layers, the last three layers, or all of the layers of rubber. The best combination of aesthetic results and manpower efficiency is attained when the last three layers of rubber applied are bullfloated within 0.5 hours of spraying.
The primary reason that bullfloating is needed with the urethane binder and not when using latex binder is that the urethane binder is much more viscous, which tends to allow the rubber to form small "piles", wherein one rubber particle will set on top of another, or where small pyramid groupings of particles would form high points. This does not occur with low viscosity latex binders. The bullfloating breaks up these undesirable groupings or high spots and forces the rubber particles into the mat by the weight of the bullfloat.
Preferably the bullfloat employed is a 4 or 5 foot wide by 6 inch deep bullfloat with a 24 to 30 foot adjustable angle handle, commercially available from Allen Engineering Corporation and sold under the RAZORBACK name. | A method and apparatus for continuously coating particulate such as rubber with liquid binder and applying the same to a substrate to form resilient athletic surfaces. Total encapsulation of the particulate with the liquid binder is accomplished prior to applying the mix to the substrate. In addition, the method of delivery of the particulate and binder maintains the ratios thereof uniform. In its method aspects, the instant invention involves separately introducing a stream of particulate and a stream of binder into a spray nozzle, where they are combined and delivered to the substrate. The apparatus includes a nozzle assembly having a central lumen and an elongated tip, the lumen being formed so as to force the particulate introduced therein to follow a circuitous or indirect path therethrough and thereby decrease its velocity prior to being ejected from the nozzle. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a method for treating a semi-conductor wafer and in particular, but not exclusively, to what is known as planarisation.
It is common practice in the semi-conductor industry to lay down layers of insulating material between conducting layers in order to prevent short circuits. If a layer of insulating material is simply deposited in the normal way undulations begin to build up as the layers pass over the metallic conductors which they are designed to insulate. Various techniques have been developed to try to overcome this problem by filling the trenches or valleys between the conductors to a height above the top of the conductors so that after treatment a generally planar layer exists on the top of the wafer. One example of such a technique is to spin on layers of polyimide to smooth out the surfaces. However, in practice, narrow trenches tend to be incompletely filled whilst wide valleys are not fully levelled. As the 2-D dimensions of devices are reduced, these problems are accentuated.
SUMMARY OF THE INVENTION
One aspect the invention consists in a method of treating a semi-conductor wafer comprising, depositing a liquid short-chain polymer having the general formula Si x (OH) y or Si x H y (OH) z on the wafer to form a generally planar layer.
The reference to the polymer being liquid is simply intended to indicate that it is neither gaseous nor solidified at the moment of deposition.
Another aspect the invention consists in a method of treating a semi-conductor wafer in a chamber including, introducing into the chamber a silicon-containing gas or vapour and a compound, containing peroxide bonding, in vapour form, reacting the silicon-containing gas or vapour with the compound to form a short-chain polymers on the wafer to form a generally planar layer.
The silicon-containing gas or vapour may be inorganic and preferably is silane or a higher silane, which may be introduced into the chamber with an inert carrier gas, for example nitrogen. The compound may be, for example, hydrogen peroxide or ethandiol.
The method may further comprise removing water and/or OH from the layer. For example the layer may be exposed to a reduced pressure and/or exposed to a low power density plasma, which may heat the layer to 40° to 120° C.
The method may further comprise forming or depositing an under layer prior to the deposition of the polymer. This under layer may be silicon dioxide and may have a thickness of between 1000 and 3000 Å. It may for example be 2000 Å thick. The under layer may conveniently be deposited by plasma enhanced chemically vapour deposition. Either the under layer and/or the wafer may be pre-treated by, for example a plasma, to removing contaminants. In that case it may be pretreated with a plasma, for example using oxygen as a reactive gas.
Similarly the surface of the deposited polymer layer may be treated in a plasma using a reactive oxygen gas in order to enhance chain lengthening and cross-linking within the polymer. This gas could be, for example, oxygen, nitrogen or hydrogen peroxide vapour and other gases may be appropriate. The plasma has a heating effect which enhances crosslinking, but there may also be a radiation effect from the various gases. This chain linking may alternatively be catalysed by exposing the polymer layer to UV light, x-rays or ion bombardment. However, in many applications acceleration of chain linking may not be desirable; instead it may be desirable for the polymer molecule particles to settle before significant chain linking occurs.
The method may further comprise depositing or forming a capping layer on the surface of the deposited layer. This capping layer may be silicon dioxide. The capping layer is deposited after a proportion of the condensation reactions have occured and water has been removed from the layer.
The method may further comprise heating the polymer layer and this heating preferably takes place after capping. The polymer layer may be heated to between 180°-220° C. for between 50-70 minutes. For example it may be heated to 220° C. for 60 minutes. The layer may subsequently be allowed to cool to an ambient temperature and then reheated to 430°-470° C. for 30-50 minutes. For example the second heating may last 40 minutes at 450° C. Indeed this second heating may suffice and may be achieved using a furnace, heat lamps, a hotplate or plasma heating.
In one preferred arrangement the polymer layer may be heated to between 200°-450° C., prior to capping, in order that the cap can be deposited at elevated temperatures. Although the capping layer could be deposited in one or more steps e.g. a `cold` capping layer deposited at the temperature of the planarising layer followed by a hot capping layer; the polymer layer having first been heated to 200°-450° C. as described above.
The density of the hydrogen peroxide may be in the range of 1.20-1.35 gms/cc and a density of 1.25 gms/cc may be particularly preferred. The hydrogen peroxide is preferably at 50% concentration when introduced into the chamber.
The ambient temperature within the chamber may be within the range of 0°-80° C. during the deposition of the polymer layer, but the wafer platten is preferably at 0° C. or at the dew point of the polymer when in vapour form. Low pressure is also desirable but requires low temperatures (eg 400 mT, -10° C.).
In order to avoid heating the platen, the wafer is preferably lifted from the platen for each processing step which involves heating.
The method can be used to achieve planarisation or gap filling. In the latter case the ambient chamber temperature may conveniently be even higher. The invention also includes wafers treated by any of the methods set out above and semi-conductor devices including polymer layers formed by the method above.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may be performed in various ways and a specific embodiment will now be described, by way of example, with reference to the following drawings, in which;
FIG. 1 is a schematic view of an apparatus for performing the treatment method;
FIGS. 2A and 2B are hugely magnified photographs of cross-sections of a wafer treated by the method; and
FIGS. 3A to 3E illustrate schematically the steps of the process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An apparatus for treating semi-conductor wafers is schematically illustrated at 10 in FIG. 1. It will be understood that only the features which are particularly required for the understanding of the invention are described and illustrated. The general construction of such apparatus is well known in the art.
Thus, the apparatus 10 includes a chamber 11 having a duplex shower head 12 and a wafer support 13. The shower head 12 is connected to RF source 14 to form one electrode, whilst the support 13 is earthed and forms another electrode. Alternatively the R.F. source 14 could be connected to the support 13 and the shower head 12 earthed. The shower head 12 is connected by respective pipes 15 and 16 to a source of SiH 4 in N 2 or other inert carrier and a source 16 of H 2 O 2 . The carrier gas is conveniently used for ease of operation of the equipment; it is believed that the process could be performed without it.
The source 16 comprises a reservoir 17 of H 2 O 2 , an outlet pipe 18, a pump 19 and a flash heater 20 for vaporising the H 2 O 2 .
In use the apparatus is arranged to deposit a short chain, inorganic polymer, which is initially a liquid, between the interconnects on a semi-conductor chip to produce planarisation either locally or globally, or for `gap filling`. The polymer is formed by introducing into the chamber the silane and the hydrogen peroxide in vapour form and reacting them within the chamber spontaneously. Once the resultant polymer is deposited on the wafer, it has been found that its viscosity is such that it fills both small and large geometries or gaps and is generally self levelling. It is believed that effectively there is a settlement process taking place as the polymerization takes place. The more settlement which occurs prior to full polymerization the less likelihood there is of cracking. Very small dimensioned gaps can be filled and because of the fill layer properties these gaps can even, in certain circumstances, be re-entrant.
As has been mentioned, if left, the chains within the polymer will slowly extend and cross link. In some circumstances it may be desirable to accelerate this process by plasma treatment. This treatment produces UV radiation and it is believed that it is this radiation which is responsible for increasing the speed of chain extension and cross linking. Other forms of radiation treatment may therefore be equally applicable. A variety of gases may be appropriate for use at this stage, for example any inert gas or hydrogen, nitrogen or oxygen containing gases.
For good quality films it is desirable to remove as much water and OH from the film at an early stage. This can be done by exposing the layer to a reduced pressure causing the layer to pump water out and the subsequently heating the layer to between say 40° C. and 120° C. A pump 22 is provided for reducing chamber pressure.
However in order to solidify fully the polymer layer, it has been found that it is generally necessary to subject the layer to more intense heat treatment. In many instances it is necessary or desirable first to deposit a capping layer over the polymer. It is believed that this assists in providing mechanical stability for the polymer layer during cross linking. It may also help to control the rate at which the layer looses water during heating and so have a controlling affect on shrinkage and cracking.
A suitable capping layer would be silicon dioxide.
The heat treatment stage after the capping involves removing excess water from the layer which is a by-product of the cross-linking reaction. The bake also removes SiOH bonds. The speed at which the water is removed may be important and several ways of removing water have been successful. One suitable sequence comprises baking the layer for 60 minutes at 200° C., cooling it to ambient temperature and then rebaking it for 40 minutes at 450° C. Microwave heating has also been successful. A simple bake at 450° C. will often also suffice, or the bakes may be replaced by the following steps:
1. 2000 Å `cold` cap deposited at between 20°-40° C.
2. Plasma heat treatment in N 2 0 which raises the temperature to 300°-400° C.
3. 4000-6000 Å `hot` cap is deposited.
Alternatively, in some cases, a single stage `hot cap` deposited at 300°-400° C. will suffice.
It has been found that the adhesion of the polymer layer to the underlying substrate material can be enhanced by depositing an under layer, for example of silicon dioxide. Typically this should be of the order of 2000 Å thickness and it may be laid down by plasma-enhanced chemical vapour deposition.
Examples of actual deposited layers are illustrated in the photographs of FIGS. 2A and 2B. It will be seen that the upper surface of the layers 21 are generally planar despite the huge magnification involved.
Although SiH 4 has proved to be particularly successful, it is believed that the method will be applicable with most silicon-containing gases or vapours. It has been found that to some extent a suitable polymer can be obtained with any concentration or density of H 2 O 2 , but a density range 1.20-1.35 gms/cc has been particularly successful. The most preferred H 2 O 2 density is 1.25 gms/cc. An H 2 O 2 concentration of 50% is very effective but it is believed that the preferred concentration may vary depending on whether the object is to achieve planarisation or gap filling. It is preferred that more H 2 O 2 is supplied than SiH 4 and it is particulary preferred that the H 2 O 2 :SiH 4 ratio is of the order of 3:1.
In the event that the wafer needs to be removed from the chamber between processing stages, it may be desirable to pre-treat the exposed surface, when the wafer is placed back in the chamber, in order to remove any organics or other contaminants from the exposed surface.
FIGS. 3A to E illustrate the preferred processing sequence schematically FIG. 3A shows formation of the underlayer 302 (adhesion enhancer) by PECVD at 300 Deg. C., with a probably chemistry of SiH 4 +2N 2 O→SiO 2 ↓ +2H 2 +2N 2 . FIG. 3B shows formation of the planarising layer 304 (planarises features), with reference numeral 306 denoting surface tension forces, by CVD at approx. 0 deg. C., with a probably chemistry of SiH 4 +3H 2 O 2 →Si(OH) 4 ↓ +2H 2 O+H 2 . FIG. 3C shows a treatment stage, i.e., a first post treatment (promotion of polymerisation and removal of water), by pumpout at approx. 0 deg. C., and pumpout at approx. 150 deg. C., with a probable chemistry of Si(OH) 4 →SiO 2 +2H 2 O↑. FIG. 3D shows formation of the capping layer 308 (provides mechanical stability during densification step) by PECVD at 300 deg. C., with a probably chemistry of SiH 4 +2N 2 O→SiO 2 ↓ +2H 2 +2N 2 . FIG. 3E shows a second treatment stage, i.e., a second post treatment (densification of film, where reference numeral 310 denotes shrinkage), by anneal at 450 deg. C. In FIG. 3A, an underlayer 301, which functions as an adhesion enhancer, is formed by PECVC at 300 Deg C. In FIG. 3B, a planarising layer 302 is formed by CVD at approximately 0 Deg. C. The resultant layer, exhibiting surface tension forces 303, provides planarising features. FIG. 3C shows a first post treatment stage for promotion of polymerisation and removal of water (H 2 O), as a result of a pumpout at approximately 0 Deg. C., and a pumpout at approximately 150 Deg. C. FIG. 3D shows formation of the capping layer 304 by PECVD at 300 Deg. C. The capping layer 304 provides mechanical stability during a next densification step. FIG. 3E show a second post treatment stage for achieving film densification (shrinkage) by annealing at 450 Deg. C. It may be advantageous to wash the chamber with H 2 O 2 between at least some of the processing stages.
As it is desirable to keep the platten or support 13 at around 0° C., the wafer may be lifted above the support 13 for each heating process so that the heat of the wafer is not significantly transmitted to the support 13. This can be achieved by arranging an intermediate position 23 for a wafer loading device 21. | A wafer processing method relates to treating a semi-conductor wafer and in particular, but not exclusively, to planarization. The method consists of depositing a liquid short-chain polymer formed from a silicon containing gas or vapor. Subsequently water and OH are removed and the layer is stabilised. | 8 |
BACKGROUND OF THE INVENTION
The invention generally relates to window safety bars and fire escapes, and more particularly to a unitary window safety bars and exterior fire escape ladder, and in which there is no loss of effectiveness of purpose and use in either category due to the other.
The prior art teaches combinations with similar purposes to put in building window casings, but in which the effectiveness of each part of the combination is reduced by the other both in purpose and use. Thus the effectiveness of purpose of the window safety bars is reduced when anyone outside a building can release the window safety bars in the window casings thereof, and the effectiveness of the exterior fire escape ladder is reduced when everyone inside the building cannot release the window safety bars. The effectiveness in use of said combinations as a fire escape ladder is reduced when access thereto is physically dangerous and difficult for the elderly, infirm, sedentary, and women, the last because of the type of clothing normally worn.
In the following references, Scholer, U.S. Pat. No. 1,629,541 teaches a safety metal grill that is locked in place and can only be used as a fire escape when the possessor of the key for the lock is present. Also the grill is pivoted to a window sill for swinging outwardly and downwardly therefrom as a fire escape ladder and thereby requiring a user to crawl out on the sill and half hanging thereover to reach backward with a foot to find a ladder rung.
Momo, U.S. Pat. No. 1,072,624 teaches a window railing lattice extendable downwardly from just above a window sill or swung outwardly therefrom for poor access.
Scherrer, U.S. Pat. No. 956,183 and 573,165 teach swinging casements with difficult access similar to Momo and requiring a 90° turn with one backward handhole.
Bessier, U.S. Pat. No. 269,377 and Chipley, U.S. Pat. No. 145,844 also teach swinging fire escape ladders, all except Chipley swinging normal to a window casing, and Chipley teaching shutters swinging 180° thereto, all posing risk of falling to gain access.
The invention teaches a unitary window safety bars and fire escape ladder for either use by anyone inside the window of a building in which it is installed. As an exterior fire escape ladder, easy access for a person within the building is provided from a standing position on a window sill facing forward and holding with both hands to horizontal side supports by taking a short step forward to a vertical ladder cantilevered outwardly from the building and descending between building and ladder to similar ladders in lower windows until the ground is reached, an escape well within the abilities of all ambulatory persons.
A second embodiment of the invention for a one story building only teaches the same spacing between safety bars and ladder rungs and backward access from standing position on a window sill with angled frame sides providing handrails and descent facing the building to the ground as in using a leaning conventional ladder.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a unitary window safety bars and exterior fire escape ladder in which the dual uses and purposes are not adversely affected by the unitary apparatus.
Another object of the invention is to provide a unitary window safety bars and exterior fire escape ladder which is usable by the elderly, infirm, sedentary, and women normally clothed.
Yet another object of the invention is to provide for one story buildings a unitary window safety bars and exterior fire escape ladder that is simpler and more economical to make and install than the embodiment for installation and use in multi-storied buildings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of the invention mounted as window safety bars in a building window casing;
FIG. 2 is a front view of the invention pivotally and slidably adjusted as an exterior fire escape ladder;
FIG. 3 is a side elevation of the invention as shown in FIG. 2;
FIG. 4 is a cross-sectional view taken along section line 4--4 of FIG. 1;
FIG. 5 is a three dimensional view of the invention as shown in FIG. 3;
FIG. 6 (a) and (b) are three dimensional enlarged views of the locking device of FIG. 1 shown (a) unlocked, and (b) locked;
FIG. 7 is a three dimensional view of a second embodiment of the invention mounted as window safety bars in a partially shown one story building;
FIG. 8 shows the matter of FIG. 7 adjusted as an exterior fire escape ladder;
FIG. 9 is a cross-sectional view taken along section line 9--9 of FIG. 7; and
FIG. 10 is a cross-sectional view taken along section lines 10--10 of FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-6, the invention comprises a pair of slidably interfitting outer and inner frames 20 and 22, each having a plurality of horizontal bars 24 and 25 respectively fixed therein spaced equally and vertically apart. A pair of side supports 26 pivotally mounts said frames, when slidably coincident, in a window casing 28 as window safety bars. A locking device 30 is operably mounted in the sides and sill of said window casing, and is operable only from inside said window casing to lock and unlock side supports 26 for pivoting said frames in and out of said window casing for extended use as an exterior fire escape ladder.
Referring particularly to FIGS. 2-5, outer frame 20 comprises elongated sides 21 made from angle stock, "L" shaped in cross-section (see FIG. 4), and extending along the sides of window casing 28 from sill 46 to lintel 47 and oppositely disposed for long side of the "Ls" to be transverse the plane of said window casing and the short side of the "Ls" to be parallel with said plane. Horizontal safety bars 24 are fixed in the long side of the "L" of the frame sides 21 extending therebetween, and a stop bar 52 is fixed between said short side of the "Ls" adjacent the sill 46 ends of said frame 20 for engaging an associated stop bar 50 of inner frame 22 as will be explained hereafter.
Inner frame 22 comprises elongated sides 23 made from channel stock, "U" shaped but with a flat base in cross-section (see FIG. 4), and extending from sill to lintel of said window casing similarly disposed to slidably engage outer frame sides 23 "L" shaped in cross-section with the flat base of the "U's" to said short side of the "L's" and opposing sides of the "U's" to opposite long sides of the "L's". Horizontal safety bars 25, shorter than safety bars 24, are fixed in the unengaged sides of the "U" of the frame 22 sides 23 and extending therebetween. A stop bar 50 is fixed to the flat bases of the "U's" adjacent the lintel end of sides 22 and adapted to engage said stop bar 52 of the outer frame 20 to prevent separation of said inner and outer frames when slidably extending downwardly. Said inner frame is slidably insertable in said outer frame from the lintel end as shown in FIG. 4 and is retainable therein by said outer frame and stop bars 50 and 52.
Referring to FIGS. 3-5, side supports 26 comprise a pair of flat bars having oppositely disposed ends 43 and 44 with transverse pivot holes 38 defined in each said end and locking slots 54 defined therebetween. Stops 42 are fixed below respective ends 44 and outboard of pivot holes 38. The side supports are pivoted to outer frame 20 by pivots 36 through pivot holes 38 in ends 44 and adjacent the frame's lintel end. Oppositely disposed support ends 43 are respectively pivoted to window casing sides 21 below the casing lintel a distance equal to that from support end 44 to lower pivot hole 38. A cable stop 40 is fixed to each support 26 intermediate its ends 43 and 44 and to each window casing side between the supports' fixed ends and lintel 47. In use stops 42 restrict the pivoting on outer frame 20 on said supports to 90°, and cable stops 40 restrict the pivoting of said supports to 90° to the window casing.
Referring to FIGS. 1, 5 and 6, locking device 30 comprises locking slots 54 defined in said window casing sides between the pivoted ends 43 of side supports 26 and cable stops 40 ends fixed to sides of window casing 28, and in alignment with locking slots 54 defined in said side supports when said supports are pivoted into said window casing. Cylinder segments 56 are respectively mounted for rotation on parallel axes 57 with flat portions of said segments respectively flush with respective locking slots 54 defined therein and rotatable to extend partially therethrough. Cylindrical members 58 are respectively mounted for rotation on parallel axes 60 in said casing sill 46 vertically below and in the same plane as cylinder segments 56 and axes 56 and 57. A pair of rods 62 respectively connect oppositely disposed horizontal radial extremities of respective vertically aligned cylinder segments with the same radial extremities of associated cylindrical members, and a similar rod 62 connects upper radial extremities of said cylindrical members. Another rod 66 connects a lower radial extremity of a cylindrical member 58 and a manual crank mechanism 61 mounted in a building wall adjacent said window casing and adapted to rotate the cylindrical member a quarter turn counterclockwise thereby rotating the other cylindrical member and both the connected cylinder segments on their respective parallel axes and in the same plane in alignment for said segments to project through said slots 54 in said casing and side support to lock the side support and frames 20 and 22 in the window casing. A quarter turn of said cylindrical member clockwise unlocks said frames from the casing (see FIG. 6 (a) and (b)). The manual crank mechanism is mounted out of reach of anyone outside the window casing and comprises a dial crank 63 fixed on the outboard end of a shaft 64 parallel to axes 57 and 60 of the rotatable members and segments 56 and 58. A lever 65 is fixed by an end normal to said shaft and in the plane of members 58. The free end of said lever 65 is connected to said rod 66 free end, whereby turning or rotating said dial crank 63 clockwise rotates said members counterclockwise, and rotating said dial crank counterclockwise rotates said members clockwise.
A second embodiment of the invention (see FIGS. 7-10) also comprises a pair of slidably interfitting frames as in the first embodiment except that an outer frame 66 is channel shaped but larger than inner frame 68 which is similar to the inner frame of FIG. 4. The change was made necessary by the absence of safety bars 24 in the outer frame for holding the inner frame 68 in operable association therewith. Side supports 26 of the first embodiment are omitted and the outer frame 66 is pivoted to window casing sides adjacent said casing lintel. In the locking device 30 of the first embodiment, the cylindrical members 58 and window casing slots 54 are omitted to provide a locking device 70 having a manual crank mechanism 61 identical with that of the first embodiment that rotate cylinder segments 56 directly to project through locking slots 71 defined in the sill of window and outer frame in alignment, said segments being mounted in the window sill.
With the first embodiment locked as window safety bars in a window casing, to adjust as an exterior fire escape ladder, anyone inside the building rotates the dial crank 63 to unlock the locking device 30 and release side supports 26 from the window casing sides. A push against the upper part of the frames 20 and 22 pivots side supports 26 outward and downward 90°, as limited by cable stop 40. Frames 20 and 22 are carried free of window sill 46 allowing the inner frame 22 to extend slidably downward by gravity until stops 50 and 52 engage to prevent separation of the frames. A person exiting the building steps on the window sill, grasps the side supports with respective hands and steps forward on to a horizontal bar now a ladder rung 24, shifting his hands to grasp the frame sides 21. The frames are prevented from swinging out around outboard pivots 38 more than normal to the side supports. The person descends supported vertically between the building and the ladder to a similar lower ladder and/or the ground, as shown in FIGS. 2 and 3. To adjust back to window bars, a person inside the building reaches out of the window grasping the frame sides 21 and lifting them upward, pivoting the side supports upwardly and inwardly until frame 22 contacts the window sill. The grasps are shifted to frame sides 23 of bars 25 and the inner frame slidably raised into coincidence with outer frame 20 and both pulled inwardly by bars 24 and 25 into the window casing 28. The person then steps to the dial crank and rotates it to lock the side supports which have also pivoted upward and inward into the window frame with the frames into the window casing.
With the second embodiment locked as window safety bars in a window casing, to adjust as an exterior fire escape ladder to the ground, anyone inside the building rotates the dial crank 63 of the locking device 30 to unlock locking device 70 and release the frames from the window sill. A push against the bottom of the frames 66 and 68 pivots them outwardly around pivots 69 adjacent the top of the frames and lintel of the window casing, clear of the window sill. Inner frame 68 slides downward until prevented from sliding out of frame 66 by stops 50 and 52 or by the ground. A person leaving the building stands facing inward on the window sill and grasping the angled sides of frame 66 steps on the horizontal bars 25 of the inner frame and descends as on a leaning straight ladder. To adjust back to window bars, the inner frame can be raised either from inside or outside the building and both frames seated in the window casing. However, the frames can only be locked in the casing by a person inside stepping to the dial crank 63, out of reach from the window, and turning it to lock the frames to the window sill. | A pair of frames are slidably interfitted on a common slide axis. Safety bars placed normal to the slide axis and alternately opposite sides of the slide axis, are fixed in the frames in sliding noninterference and for halving space between bars when frames are slidably coincident. Frames are pivotally fixed in the lintel or upper half of a building window casing for pivoting outwardly. A locking device, mounted in a window casing and controllable by anyone in the building and remote from the casing, locks the frames slidably and pivotally coincident in the casing as closely spaced window safety bars, and similarly unlocks the frames to pivot them outwardly clear of the window sill for slidable extension downwardly as an exterior fire escape ladder with double spaced rungs and angled handrails for standing entry on the ladder from the window sill. Bar stops fixed to opposite ends of the respective frames prevent separation of the slidably interfitting frames. | 4 |
BACKGROUND
In known looms of this type, the bulges in the teeth of the reed which form the guide channel for the fluid are so developed and the reed is so controlled in its forward and backward movement that the filling thread inserted remains in the guide channel during the beating-up and emerges from the guide channel only upon the subsequent rearward movement of the lay. The beating-up of the filling threads therefore is effected by the portions of the teeth of the reed which form the lowest point in the bulges.
With this known development, difficulties result with regard to the shaping and arrangement of the stretchers necessary to obtain a proper fabric. If the stretchers are of conventional development, they cannot be arranged at a sufficiently small distance in front of the place where the filling thread is beaten-up, since on the one hand the teeth of the reed have portions which extend forward beyond the place of beating-up in the beating-up position, said portions having the flanks of the bulges which form the guide channel, while on the other hand there is no room for the stretchers in the cross-section of the guide channel. However, an insufficiently small distance between the beating-up point and the stretchers results in the disadvantage that upon the beating-up of the filling yarn, the fabric shrinks somewhat in its width and as a result the warp yarns are no longer parallel in the regions of the edges of the shed, which may impede the movement of the reed and lead to a scraping of the teeth of the reed against the warp yarns. In order to exclude this disadvantage, it has been attempted to adapt the development of the stretchers and of the bulges of the reed teeth which form the guide channel to each other in such a manner that the stretchers enter the guide channel upon the beating-up movement of the reed. This, however, requires a special flat construction of the stretchers which is of little strength and is less protective of the cloth than the traditional stretchers for which there is no room in the cross-section of the guide channel.
Looms are also known in which the devices for the insertion of the filling yarns by means of a fluid have a comb of parallel confusor blades, each having a bulge to form the guide channel for the fluid serving for the insertion of the filling yarn, the confusor blades being separated from the reed teeth but being firmly connected with the lay in such a manner that they emerge completely from the shed during the beating-up movement of the lay so as to enable the reed to beat-up the filling yarn which has been previously inserted and upon the subsequent rearward movement of the lay again to move between warp yarns in order upon the next insertion of the filling yarn to provide the desired guidance within the shed of the fluid which inserts the warp yarn. With this development of the machine, the reed can be provided in conventional manner with linearly extending reed teeth and it is possible to mount the stretchers of ordinary construction sufficiently close to the fell of the cloth so that no problems occur in this respect. On the other hand, with this development of the loom, the insertion of the confusor blades between war yarns after the beating-up of each filling yarn is not without difficulties since at times a warp yarn may be caught on a confusor blade which leads to weaving defects and may cause the breaking of warp yarns.
SUMMARY
The present invention relates to devices for a loom of the aforementioned type capable of functioning in such a way, in a relatively simple manner, in order to avoid the above-described disadvantages of known embodiments that either require confusor blades which move in and out between warp yarns or special stretchers in order to be able to maintain the desirably small distance between the fell of the cloth and the stretchers. Therefore, the devices of the present invention will accommodate stretchers of conventional construction since they can be mounted directly in front of the fell of the cloth.
The objects of this invention are achieved essentially in a loom of the aforementioned type in the manner that an at least approximately linear portion of the tooth smoothly joins the bulge of each reed tooth and the forward and backward movement of the reed is conducted in such a manner that the bulges of the reed teeth lie within the shed when the reed is in the position in which the insertion of the filling yarn takes place and the linear portion of the reed tooth is located at the place of beating-up when the reed is in the filling-yarn beating-up position.
With this development the result is obtained that the filling yarn which is introduced into the guide channel by means of a fluid insertion, for instance compressed air, during the beating-up movement of the lay comes out of the bulges of the reed teeth and comes to lie in front of the linearly extending portions of the reed teeth and that the beating-up of the filling yarn against the cloth which has already been woven is effected by means of the linear portions of the reed teeth. The stretchers can therefore be arranged without difficulty at a sufficiently small distance from the place where the warp yarn is beaten-up even if they are of conventional development since upon the beating-up of the filling yarn the stretchers do not have to enter into the guide channel formed by the bulges in the reed teeth. Nevertheless there are no confusor blades to be moved in and out between warp yarns and which could give rise to weaving defects and the breaking of warp yarns. In one suitable embodiment the linearly extending portion and the adjoining flank of the bulge of each reed tooth are at an angle of between 135° and 180° and preferably 150° to 180° to each other while the other flank of the bulge and the linearly extending portion of each reed tooth are advantageously at an angle of about 90° apart.
The reed is preferably moved back and forth in known manner by means of swingably supported lay swords. In a preferred embodiment of the invention, the path of movement of the bulge of each reed tooth may extend along a circular arc which obliquely intersects the group of warp yarns facing the axis of swing of the lay swords when the shed is open and the linearly extending portion of the reed teeth, when the reed is in the beating-up position, extends at least approximately at right angles to the middle warp-yarn direction and is inclined with respect to a line radial to the axis of swing of the lay swords which passes through the vertex of the bulge.
BRIEF DESCRIPTION OF THE DRAWINGS
Further details of the invention will become evident from the following description of specific embodiments and from the corresponding drawings which show the subject matter of the invention diagrammatically and by way of example, and which merely illustrate the subject matter of the invention, in which:
FIG. 1 shows in vertical view along the warp yarns a portion of a loom having the device of this invention, the device shown in solid lines in its position upon the insertion of the filling yarn, and in dot-dash lines in its position at the beating-up point of the filling yarn;
FIG. 2 shows a partial vertical view of an individual reed tooth of the part of the loom shown in FIG. 1;
FIG. 3 shows a second embodiment of reed tooth similar to the part of the loom illustrated in FIG. 1; and
FIG. 4 shows a partial vertical view of an individual reed tooth of the part of the loom shown in FIG. 3.
DESCRIPTION OF PREFERRED EMBODIMENTS
The loom shown in FIG. 1 has a lay 11 which bears a reed 12. The lay 11 is supported by lay swords 13 which are swingable around an axis lying outside the plane of the drawing. In known manner the lay swords 13 are so driven by cranks or eccentrics (not shown) of the main shaft of the loom via connecting rods that upon rotation of the main shaft a backward and forward swinging movement of the lay swords 13 and of the lay 11 takes place.
The reed 12 has blade shaped reed teeth 20 only one of which is visible in FIG. 1 since the reed teeth cover one another. Between the reed teeth there pass in customary fashion warp yarns 21 and 22 which, together with the filling yarns (not shown) form the cloth 23 which is to be produced. The shed 24 necessary for the insertion of the weft yarns between an upper group of warp yarns 21 and a lower group of warp yarns 22 is formed in known manner (not shown) by means of shafts. The beating-up of the previously inserted filling yarn against the cloth 23 which has already been produced is effected at the beating-up point (fell) 25 by means of the teeth 20 of the reed 12, as is generally known. At a slight distance from the beating-up point 25 there are located stretchers 26 of customary development each of which, by means of a fixed part 27 and a rotating part 28, grasps the selvage or edge portions of the cloth 23 produced and continuously pulls same outward so as to stretch the cloth in width so that the warp yarns 21 and 22 of the upper and lower groups of warp yarns always extend parallel towards the beating-up point 25.
Each reed tooth 20 is provided on the front side thereof facing the fell 25 with an inwardly directed bulge 30 which has its opening facing the fell 25. The bulges 30 of all the reed teeth 20 coincide with each other and together form a guide channel for a fluid serving for the insertion of the filling yarn, for instance compressed air. The said fluid is fed by means of a main nozzle located on one side of the shed and a plurality of auxiliary nozzles 31 from hoses 32 from a fluid source means 32A. The auxiliary nozzles 31 are distributed at suitable distances apart along the lay 11 and fastened to the lay. The outlet openings 33 of the nozzles 31 are so arranged and directed that a stream of fluid is produced in the guide channel formed by the bulges 30 transversely through the shed 24 when the nozzles are placed in operation. Immediately above the bulge 30, each reed tooth 20 has a linearly extending portion 34 which smoothly or directly joins the bulge 30. The said linearly extending portion 34 of the reed teeth serves for beating-up the previously introduced filling yarn against the cloth 23 which has already been produced.
The axis of swing of the lay swords 13 has a position which is so set back with respect to the beating-up point 25 that upon the forward and backward movement of the lay 11 the bulge 30 of each reed tooth 20 moves along an arcuate path 35 which obliquely intersects the lower group of warp yarns 22 in the open position of the shed. The guide channel for the fluid serving for the insertion of the filling yarn which is formed by the inwardly directed bulges 30 is located within the shed 24 when the lay 11 is moved towards the rear (towards the right in FIG. 1) into the filling yarn insertion position and is outside the shed when the lay 11 is moved into the filling yarn beating-up position (dot-dash lines in FIG. 1). In said last mentioned position of the lay 11, the linearly extending portion 34 of each reed tooth 20 is located at the beating-up point 25.
In order that the filling yarns can be properly beaten-up by the linearly extending portion 34 of each reed tooth 20, the reed 12 is so arranged that in the beating-up position of the reed the said linearly extending portion is approximately perpendicular to the middle direction 36 of the warp yarn and is thus not radial to the axis of swing of the lay swords 13 but differs by an angle α which lies for instance in the range of 25° to 30° from a radial line 37 to the axis of swing of the lay swords which passes through the vertex of the bulge 30.
As shown in the detailed view of FIG. 2, the bulge 30 of each reed tooth 20 has two approximately linear extending flanks 38 and 39 which are connected to each other by a circular arc 40 forming the vertex portion of the bulge. In the embodiment shown, the two extending flanks 38 and 39 form with each other an angle β which is approximately 60°, the linearly extending portion 34 and the adjoining upper flank 38 being at an angle γ to each other of about 150° while the lower flank 39 is approximately perpendicular to the linearly extending portion 34. By this development of the bulge 30, the result is obtained that on the one hand the filling yarn introduced by means of the fluid is secured by the lower flank 39 from dropping down while on the other hand upon the beating-up movement of the lay 11 the filling yarn slides along the upper flank 38 out of the bulge 30 to in front of the linearly extending portion 34 of each reed tooth 20 on a ridgeless smooth surface while the bulge 30 moves out of the shed 24 along its arcuate path of movement 35 (see FIGS. 1 and 3).
The manner of operation of the devices for the insertion and beating-up of the filling yarns which have been described is as follows:
When the lay 11 moves into its upper dead center position, i.e. into its greatest possible distance from the filling yarn beating-up point 25, the reed 12 and the nozzles 31 assume the solid line positions shown in FIG. 1. While the bulge 30 of each reed tooth 20 is within the open shed 24 and the nozzles 31 extend between warp yarns 22 of the lower group of warp yarns also into the shed 24, a filling yarn is introduced by the fluid flowing out of the main nozzle and the fluid from the auxiliary nozzles into the guide channel formed by the bulges 30 of the reed teeth 12. Upon the subsequent forward movement of the lay 11 towards the beating-up point 25, the bulges 30 of the reed teeth 12 move along the arcuate path of movement 35 obliquely downward out of the shed 24. In this connection the previously inserted filling yarn is moved by the reed 12 against the beating-up point 25 but it is prevented by the lower group of warp yarns 22 from following along in the downward movement of the bulges 30 of the reed teeth. Therefore, the filling yarn slides along the upper flank 38 of the bulges 30 upward until it emerges completely from the bulges and comes to lie in front of the linearly extending portion 34 of the reed teeth 12. When the lay 11 and the reed 12 assume the position shown in dot-dash outline as in FIG. 1, the filling yarn is beaten-up by the linearly extending portion 34 of the reed teeth 20 against the previously produced cloth 23 at the point 24 which is located in the immediate vicinity of the stretchers 26. Since the nozzles 31 are firmly arranged on the lay 11 and do not move relative to the reed 12, the nozzles move downward out of the shed upon the said beating-up movement of the lay 11 before the reed comes into the vicinity of the beating-up point 25. The beating-up of the filling yarn is therefore in no way impeded by the nozzles 31.
After the filling yarn has been beaten-up against the cloth 23, the lay 11, together with the reed 12 and the nozzles 31, moves back in opposite direction into the position which permits the introduction of the filling yarn, whereupon the processes described are repeated.
It will be appreciated that the values indicated in the above-described embodiment for the angles α, β, and γ can vary within limits. Thus, for instance, the angle β can be reduced to 45°, in which case the angle α assumes a value of 135°. Values of less than 45° for the angle β and 135° for the angle γ are inadvisable, since in such case the sliding of the filling yarn out of the bulges 30 along the upper flank 38 is made difficult or even impossible. Conversely, it may be advantageous to increase the angle β to for instance about 75°, in which case the angle γ assumes a value of about 165°. In the extreme case, the angle β may even amount to about 90° and the angle γ to 180°, as shown in the embodiment of FIGS. 3 and 4.
The second embodiment, shown in FIGS. 3 and 4, will be described below only with reference to its differences from the first embodiment. The same reference numbers as in FIGS. 1 and 2 have been used for identical parts. The main difference resides in the shape of the reed teeth. In the embodiment of FIGS. 3 and 4 reed 112 has bladelike reed teeth 120, each of which is provided with a bulge 130 on the front side thereof facing the beating-up point 25. This bulge 130 has two linearly developed flanks 138 and 139 which are connected to each other by an arcuate vertex portion 140. The two flanks 138 and 139 form an angle β' with each other which is substantially about 90°. The one flank 138 passes smoothly and without change of direction into a linearly extending portion 134 which serves to beat the inserted filling yarn against the cloth 23 which has already been formed. The other flank 138 is approximately perpendicular to the said linearly extending portion 134.
The axis of swing (located outside the sheet of the drawing) of the lay swords 13 is so far towards the rear with respect to the beating-up point 25, i.e. to the right in FIG. 3, that upon the backward and forward movements of the lay 11, the bulge 130 of each reed tooth 120 passes over an arcuate path of movement 135 which obliquely intersects the lower warp yarns 22 when the shed is open. The reed 120 is so arranged that in the beating-up position, shown in dot-dash line, the linearly extending portion 134 of each reed tooth is approximately perpendicular to the middle warp-yarn direction 36. This means that the said linearly extending portion 134 is not radial to the axis of swing of the lay swords 13 but is inclined with respect to a line 137 radial to the axis of swing rearward by an angle α' which is equal, for instance, to about 30°.
The manner of operation of the reed 112 and of the devices for the insertion of the filling yarns by means of a fluid is in principle the same as in the case of the first embodiment and therefore no description thereof is deemed necessary.
The second embodiment has advantages over the first embodiment since during the beating-up movement of the reed 112 the previously inserted filling yarn slides more easily out of the guide channel formed by the bulges 130 upwards to and in front of the linearly extending portions 134 of the reed teeth which serve for the beating-up of the filling yarn. On the other hand, however, there is the advantage in the case of the first embodiment that the jet of fluid emerging from the nozzles 31 is better held together in the guide channel, since the angle β is less than the angle β' forming the guide channel.
It is clear that in each of the embodiments of the invention described, the filling yarn beating-up point 25 lies at a very small distance from the stretchers 26 although these stretchers are of conventional construction and although no confusor blades, which are separate from the reed teeth and would have to be periodically moved out of the warp yarns and then introduced again between them, are necessary for the forming of the guide channel for the fluid serving for the insertion of the filling yarn.
It will be appreciated that various changes and modifications may be made within the skill of the art without departing from the spirit and scope of the invention illustrated and described herein. | The present invention relates to devices for use in a loom for fluid insertion of the filling yarn, the loom having a reed, each of whose teeth defines a bulge with the opening of the bulge facing the fell of the cloth being woven to provide for better beat-up, all of said bulges together forming a guide channel for the passage of fluid which serves for the insertion of the filling yarn. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/753,307 filed on Jan. 16, 2013, the entire contents of which are herein incorporated by reference.
BACKGROUND AND SUMMARY
A post hole digger attaches to the standard three point hitch of the tractor is powered by the tractor's power take-off (PTO). The digger comprises an auger without protrusions or other extending parts above the fighting of the auger, to reduce the possibility of a user becoming ensnared during use of the digger.
A gearbox translates rotation from the PTO shaft to the auger. In a traditional post hole digger, the auger's shaft attaches to the gearbox via a cross bolt that extends perpendicularly through the shaft. The cross bolt has the disadvantage of protruding from the shaft, and causing potential harm to a user. The digger of the present disclosure removes this disadvantage by providing a threaded fitting between the shaft and the gearbox. However, a threaded fitting on the rotating shaft provides an additional challenge When the auger needs to be removed from the gearbox.
The gearbox lock mechanism of the present disclosure comprises a collar coupled to a lower end of the gearbox, the collar rotatable upon operation of the gearbox. The collar comprises a semi-circular outer edge and a flat side. A male-threaded nipple extends from the collar and threads into the auger shaft. A lock bar is coupled to the gearbox and acts as a positive lock to lock the collar in place for removal of the shaft from the gearbox. The lock bar is rotatable from a locked position whereby the lock bar is aligned with and contactable with the flat side of the outer edge of the collar, to an unlocked position whereby the lock bar does not contact the flat side of the outer edge of the collar.
For purposes of summarizing the invention, certain aspects, advantages, and novel features of the invention have been described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any one particular embodiment of the invention. Thus, the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.
BRIEF DESCRIPTION OF THE DRAWINGS
The disclosure can be better understood with reference to the following drawings. The elements of the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the disclosure. Furthermore, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is a side plan view of a post hole digger coupled to a tractor.
FIG. 2 is a rear perspective view of the post hole digger of FIG. 1 .
FIG. 3 is a bottom perspective view of the digger.
FIG. 4 is an enlarged detail view of the digger of FIG. 3 , taken along detail line A of FIG. 3 .
FIG. 5 is a rear plan view of the digger of FIG. 1 .
FIG. 6 is an enlarged detail view of the digger of FIG. 5 , taken along detail line B of FIG. 5 .
FIG. 7 is a cross sectional view of the digger of FIG. 6 , taken along section lines C-C of FIG. 6 .
FIG. 8 is a partial enlarged bottom view of the digger of FIG. 6 .
DETAILED DESCRIPTION
FIG. 1 is a side plan view of a post hole digger 10 . The digger 10 is shown installed on a tractor 7 and is used to dig generally-cylindrical holes (not shown) in the ground 8 , for example, holes for fence posts. The digger 10 is disposed at the rear of the tractor 7 between the rear wheels 9 a and 9 b ( FIG. 2 ) of the tractor 7 .
The digger 10 comprises an auger 13 for drilling into the ground 8 . The digger 10 is disclosed in U.S. Non-Provisional Patent Application Serial No. 13/548,836, titled “Post Hole Digger,” published on Jan. 17, 2013, under Publication No. US-2013-0014997-A1, which is incorporated herein by reference in its entirety.
The auger 13 is supported by a top support arm 18 that extends from the tractor 7 . A rotating shaft 17 extends from a PTO shaft 20 ( FIG. 2 ) of the tractor 7 and translates rotation from the PTO shaft 20 to a gearbox 12 , and ultimately to the auger 13 . A shield 19 covers moving parts (not shown) of the gearbox 12 that could otherwise pose a safety hazard to users not shown) of the digger 10 .
FIG. 2 is a rear perspective view of the digger 10 installed on the tractor 7 between the rear wheels 9 a and 9 b of the tractor 7 . The digger 10 connects to the tractor's standard three point hitch that is known in the art. The term “three point hitch” refers to the three mounting points of a tractor hitch that extend rearwardly from the rear of the tractor 7 .
The top support arm 18 is rotatably affixed to the shield 19 that covers the gearbox 12 . A support frame 25 supports the top support arm 18 . The shield 19 is rigidly affixed to the gearbox 12 , and is not detachable from the digger in this embodiment without making the digger non-fictional, to provide safety for the user.
The rotating shaft 17 is releasably coupled to the PTO shaft 20 of the tractor 7 . As known by persons of skill in the art, a power-take off shaft is a splined shaft that is rotatable by the user (not shown) upon actuation of the tractor controls (not shown). Rotation of the PTO shaft 20 typically powers farming implements such as the digger 10 . The rotating shaft 17 extends from the PTO shaft 20 to the gearbox 12 , as further discussed herein.
The gearbox 12 is a right angle gearbox that receives rotation from the rotating shaft 17 and translates the received rotation to the auger 13 . In this embodiment, the auger 13 comprises a rotatable auger shaft 33 , a plurality of fighting blades 14 and a cutting head 15 . The cutting head 15 is disposed at the lowermost end of the shaft 33 , and comprises a pilot bit 16 and a pair of cutting blades 34 . The fighting blades 14 are disposed above the cutting head 15 .
The outer surface of the shaft 33 is generally smooth above the fighting blades 14 , and has no protrusions or other irregularities above the fighting blades 14 that may ensnare or entangle a user during use. This is an improvement over prior art augers which contain protrusions from the shaft that can endanger a user.
FIG. 3 is a bottom perspective view of the digger 10 . The gearbox 12 is disposed beneath the shield 19 , The auger 13 comprises a shaft 33 that extends from the gearbox 12 . Between the gearbox 12 and the flighting 14 , the shaft 33 is smooth, i.e., has no protrusions that could catch on a user or the user's clothing.
FIG. 4 is an enlarged detail view of the digger 10 of FIG. 3 , taken along detail “A” of FIG. 3 . A collar 63 extends beneath the gearbox and is rigidly affixed to a male-threaded nipple 64 that releasably affixes the shaft 33 to the gearbox 12 . In the illustrated embodiment the collar 63 is unitary with the nipple 64 . The collar has a semi-circular outer edge 65 that is primarily semi-circular and has a flat side 66 . The collar 63 , threads 64 and shaft 33 rotate when the digger 10 ( FIG. 1 ) is in operation.
A lock bar support 61 is coupled to the gearbox 12 between the collar 63 and the gearbox 12 . The lock bar support 61 does not rotate. A lock bar 60 is rotatably coupled to the lock bar support 61 via a fastener 62 .
When the digger 10 is in operation, the lock bar 60 is in an “unlocked” position such that the lock bar 60 extends downwardly. When the user desires to remove the auger 13 ( FIG. 3 ) from the gearbox 12 , the user manually moves the lock bar 60 to a “locked” position such that the lock bar 60 is rotated upwardly until it contacts the lock bar support 61 . In this orientation, the lock bar 60 is generally parallel to the flat side 66 of the collar 63 . When the lock bar 60 is in the locked position, the flat side 66 contacts the lock bar 60 and prevents the collar 63 from rotating. Thus the term “locked” refers to the collar 63 being locked such that it cannot rotate, and the term “unlocked” refers to the collar being rotatable. When the collar 63 is locked, the user can remove the auger 13 from the digger 10 by unscrewing the shaft 33 from the threaded nipple 64 .
FIG. 5 is a rear plan view of the digger 10 of FIG. 1 . The lock bar support 61 is rigidly coupled to a bottom side 68 of the gearbox 12 . In one embodiment, the lock bar support 61 is affixed to the gearbox 12 via a plurality of fasteners (not shown). The lock bar support 61 is generally parallel to the collar 63 . The lock bar 60 extends downwardly from the lock bar support 61 when the lock bar 60 is in its unlocked position, as shown. In this unlocked position, the lock bar 60 is generally perpendicular to the lock bar support 61 and the collar 63 .
FIG. 6 is an enlarged detail view of the digger 10 of FIG. 5 , taken along detail line “B” of FIG. 5 . The lock bar 60 is shown in its unlocked position. From this unlocked position, the lock bar 60 is rotatable upwardly in the directly indicated by directional arrow 67 . The lock bar 60 is generally rectangular, with long opposed sides extending downwardly when it is in the unlocked position.
The lock bar support 61 is comprised of a generally fiat support plate 82 and a downwardly extending tab 80 that is generally perpendicular to the support plate 82 . The lock bar 60 is rotatably affixed to the tab 80 via the fastener 62 , which may be a bolt and nut. The support plate 82 and tab 80 are made of steel in one embodiment, though other suitably strong and rigid materials could be used.
FIG. 7 is a cross sectional view of the digger 10 of FIG. 6 , taken along section lines C-C of FIG. 6 , with the lock bar 60 shown in its unlocked position. In this position, the lock bar 60 cannot contact the collar 63 , thus the collar 63 is free to rotate. The support plate 82 of the lock bar support 61 is a curved plate with a generally flat cross section and is coupled to the gearbox 12 via a plurality of fasteners 74 . Note that the support plate 82 is coupled to the non-rotatable outer body of the gearbox 12 , in contrast with the collar 63 , which rotates upon operation of the gearbox 12 . The support plate 82 extends over halfway around the gearbox 12 when viewed from the bottom as shown.
The lock bar support 61 further comprises a block stop 81 that is rigidly affixed to the support plate 82 adjacent to the lock bar 60 when the lock bar 60 is in the locked position. The block stop 81 comprises a generally rectangular box, generally made of steel, that is substantially parallel to and spaced apart from the flat side 66 of the collar 63 when the collar 63 is locked. The block stop 81 being spaced apart from the flat side 66 creates a gap 75 between the block stop 81 and flat side 66 . The width of this gap 75 , i.e., the distance “D” between an inner surface 83 of the block stop 81 , is slightly larger than a width “W” of the lock bar 60 . This is desired because when the lock bar 60 is locked, it is disposed between the inner surface 83 of the block stop 81 and the flat side 66 of the collar 63 .
The outer edge 65 of the collar 63 comprises the flat side 66 and a semi-circular portion 68 that extends more than 270 degrees around the collar. In other words, the flat side 66 in effect “cuts off” the outer edge 65 , generally less than 90 degrees around the outer edge 65 . Corners 70 and 71 on the outer edge 65 provide a transition from the semi-circular portion 68 to the flat side 66 of the outer edge 65 .
Note that the distance “D” must be sufficient so that the semi-circular portion 68 of the outer edge 65 of the collar 63 clears the block stop 81 when the lock bar 60 is in the unlocked position.
When the lock bar 60 is locked, the lock bar 60 is generally parallel to the flat side 66 of the collar 63 and the inner surface 83 of the block stop 81 . If the collar 63 is urged to rotate in either direction indicated by directional arrow 73 , one of the corners 70 or 71 will contact an inner side (not shown) of the lock bar 60 and prevent the collar 63 from further rotation, thus providing a positive lock to prevent the collar from rotation.
FIG. 8 is a partial enlarged view of the digger 10 showing a bottom perspective view of the gearbox 12 . The block stop 81 is spaced apart from the flat side 66 of the collar 63 as discussed above, creating the gap 75 . The lock bar 60 is disposed within the gap 75 , and generally contacts the support plate 82 when the lock bar 60 is in the locked position. | The gearbox lock mechanism for a post bole auger has a collar coupled to a lower end of a right angle gearbox, the collar rotatable upon operation of the gearbox. The collar comprises a semi-circular outer edge and a fiat side. A male-threaded nipple extends from the collar and threads onto the auger shaft. A lock bar is coupled to the gearbox and acts as a positive lock to lock the collar in place for removal of the shaft from the gearbox. The lock bar is rotatable from a locked position whereby the lock bar is aligned with and contactable with the flat side of the outer edge of the collar, to an unlocked position whereby the lock bar does not contact the flat side of the outer edge of the collar. | 4 |
RELATED PATENT DOCUMENTS
Related documents are coowned U.S. Pat. No. 5,276,970 of Wilcox, and U.S. Pat. No. 4,789,874 of Majette—and also U.S. patent application Ser. No. 08/657,722 in the names of Armiñana et al., issued as U.S. Pat. No. 5,992,969. Each of these documents in its entirety is incorporated by reference into this present document.
FIELD OF THE INVENTION
This invention relates generally to machines and procedures for printing text or graphics on printing media such as paper, transparency stock, or other glossy media; and more particularly to a scanning thermal-inkjet machine and method that construct text or images from individual ink spots created on a printing medium, in a two-dimensional pixel array. It is most particularly applicable to large-format printer/plotters.
BACKGROUND OF THE INVENTION
(a) Encoders in incremental printing—Most large-format incremental printers use a linear encoder in determining and controlling printhead-carriage position and called “codestrip”, tensioned along the scan-axis structure, and an encoder sensor that is assembled on the carriage—with a groove for the strip.
The sensor electrooptically reads markings on the taut strip. Associated electronics generates electronic pulses for interpretation by circuitry in the printer.
Some early tensioned encoder strips were all plastic, adequate for small, desktop printers but not for larger printer/plotter machines. Other early strips were glued to the carriage-supporting “beam” structure, but such a solution gave up the advantages of a separate tensioned strip—including much easier assembly and disassembly, on the assembly line as well as in the field.
Representative work of recent years in codestrip refinement appears in the Wilcox and Armiñana documents mentioned above. Such work in electronic interfacing appears in the Majette patent.
(b) Alignment—Accurate readings, and also minimization of noise in operation, require good alignment between the strip and sensor. Maintaining such performance reliably over the life of a product requires avoiding friction and wear—which in turn makes alignment even more important.
In the evolution of large-format printer/plotters, recent developments have tended toward use of these devices to print wider and wider mechanical drawings and posters. Of course these applications require wider-bed printing machines with correspondingly longer codestrips.
Alignment, however, is progressively more difficult for longer codestrips, partly because of the tendencies to sag under the influence of gravity and twist slightly due to very small variations in mounting angle at each end of the strip. A particularly problematic cause of misalignment is vibration in the working environment.
Vibration sources include impacts from nearby industrial construction, heavy motor traffic, elevators within the building and the like. Nevertheless, for codestrips of the type introduced in the Armiñana document, alignment has been under good control heretofore in systems having modest overall carriage travel—below about one meter (roughly three feet).
(c) The one-meter barrier—More recently it has been noted that performance for strips spanning about 107 cm (3½ feet) is acceptable, but only marginally so. A current generation of these machines requires encoder strips with spans of 152 cm and 183 cm (five and six feet respectively). In a machine of this size the associated long dimensions of the strip cause failures in functional-vibration tests, particularly in large-amplitude harmonic movement near the middle of the strip.
This vibration can produce bad readings from the sensor. For instance the counter may miss counting one or more scale graduations on the encoder strip. The result can be significant errors in a printed image.
In cases that are even more serious, vibration causes complete disassembly of the sensor system—as the strip jumps entirely out of the sensor groove. In such cases trained service personnel may be required to restore normal operation.
Damage to the strip can occur, and the sensor too may require repair. To prevent such problems the system is programmed to shut down the carriage servocontrol motor if the sensor system is able to detect that it has lost count of the encoder graduations—as for example if it loses the pulse train completely.
If such a loss of count occurs while the carriage is near either end of the mechanism, and moving rapidly toward that end, this safety override may not have enough time to stop the carriage before it reaches the end bulkhead. Considerable damage to the carriage and other parts of the mechanism can result.
For machines of modest size it is sufficient to provide a mechanical limiter that simply retains the strip within the sensor groove. The limiter and its installation represent undesirable added cost.
This simple solution, moreover, has proven inadequate for a strip over 1½ m long. Even though retained within the sensor, the strip undergoes oscillations large enough to make sensor measurements erratic and unreliable.
People familiar with this field will understand that the “barrier” suggested in the title of this subsection is not an abrupt step at precisely one meter. Rather the difficulty in achieving satisfactory codestrip arrangements increases progressively over a considerable range from, perhaps, less than one meter to two or possibly three meters. Nevertheless there is a clear qualitative difference, between lengths under one meter and lengths of, say, several meters.
(d) An overconstrained problem—The encoder strip is a rather simple mechanical article, but those skilled in the art will recognize that this seeming simplicity may be very deceptive. The strip interacts in subtle ways with several different complex components of the system.
As a result, it is not at all obvious how to overcome the difficulties outlined above. Some of the more-evident candidate solutions are impractical, due to certain persistent constraints.
The progressively larger machine formats, even below the one-meter barrier suggested earlier, have called for greater tension in the strip. Beyond that barrier, simple increase of tension in the strip is unacceptable.
One reason is that higher tension could potentially introduce safety concerns. Another reason is that higher tension in the strip can cause small twists and other irregular deformations in the associated mechanism. Even if microscopic, such interference with the straightness and structural integrity of the guide-and-support rods and beam can throw off the positional calibration of the whole carriage drive system.
Such potential damage can be difficult to detect, and the design cost of reevaluating the entire mechanical system for such potential damage is in itself severe. If found, such a problem can be compensated only by strengthening the entire structure. Beefing up the mechanism in that way, in turn, would entail additional weight and cost.
Another complication is that addition of stiffening elements or any other attachment to the strip itself would be extremely awkward, since the sensor groove is very narrow. Of course it is important not to add anything to the strip, or next to it, that might pose even greater risk of damage than the strip itself poses—that is to say, catastrophic failure modes must be evaluated as carefully as routine operation.
Thus a supporting ledge below the codestrip (reasonably remote from the moving sensor) might be useful, although costly, but it would not resolve the problem of the strip moving upward. A “ceiling” strip immediately above the codestrip, to correct that deficiency, does not appear practical since the encoder sensor—moving at high speed—could strike such a component.
It has been suggested to return to the approach of using adhesive to secure a strip to a solid beam structure. As mentioned earlier, however, that approach has associated inefficiencies and high costs. Such a beam-mounted encoder strip is also difficult to install and remove.
Using small screws or bolts to fix a thin metal strip along the base would be even more undesirable. The assembly time required to thread in several screws is a significant cost in terms of modern production engineering. A separate rigid structure—to be bolted into place on the beam—would be still more impractical.
Still another difficulty of earlier codestrip designs relates to the dimension stack. The dimension stack is the group of geometrical dimensions that must be algebraically added to calculate the relative position between two specified parts.
Every dimension has a tolerance. If the number of dimensions is large—i. e. if the dimension stack is “long”—the tolerance can become very large, which is very undesirable.
The pertinent parts in this case are the encoder strip and sensor, and the most problematic dimension is vertical alignment between the graduations and the sensor. For use of standardized parts and good performance, clearance between the top of the strip and the top of the sensor groove is only about two millimeters; and the graduations are roughly just four millimeters tall.
Accordingly in one common failure mode the codestrip strikes the upper end of the groove. In another, as mentioned earlier, the downward-moving codestrip entirely leaves the groove.
Making the groove substantially taller would result in greater noise levels in the electronics system. It would also implicate still further problems of mechanical alignment between parts.
The encoder dimension stack for large-format printer/plotters is in fact undesirably lengthy. It is long primarily because of the tensioned mounting system—and also because the codestrip itself in these wide-bed systems is literally long, leading to large variations in vertical position at each point along the strip.
In particular, the stack for the vertical relationship between the encoder-scale graduations and the immediately adjacent sensor includes the mounting tolerances within the sensor, and tolerances of the sensor mounting to its carriage. Next the stack continues through the carriage, and the carriage bushings, to the rods—then the beam, then the codestrip, and finally tolerances within the strip to the scale graduations.
As a result, variation between machines, as to the vertical sensor-to-scale alignment, is very large. Mounting and configuration of the strip itself, however, accounts for much of this variation.
Finally, an ideal solution should be one that is amenable to routine incorporation into not only 1½ to 2 m printers but also into both smaller and larger systems. For instance, a solution should be usable in 107-cm units previously described as “marginal” in encoder-strip performance, and also in 3 m or 7 m systems.
It would be an added bonus to find a solution that could be implemented in a retrofit mode for any smaller systems installed in especially problematic (high vibration) environments. As this discussion shows, the codestrip problem is a particularly knotty one that defies easy solutions.
(e) Conclusion—Codestrip instabilities have impeded the extension of uniformly excellent incremental printing to images well over a meter wide. Thus important aspects of the technology used in the field of the invention remain amenable to useful refinement.
SUMMARY OF THE DISCLOSURE
The present invention introduces such refinement. In its preferred embodiments, the present invention has several aspects or facets that can be used independently, although they are preferably employed together to optimize their benefits.
In preferred embodiments of a first of its facets or aspects, the invention is an encoder strip for use in incremental printing. More specifically the strip is for use with mounting means that include a series of spaced pins for nonfastening support and alignment of the strip.
The encoder strip includes an elongated member defining incremental-printer encoder indicia. It also includes a series of spaced apertures formed in the elongated member for nonclamping engagement with the spaced pins.
The foregoing may constitute a description or definition of the first facet of the invention in its broadest or most general form. Even in this general form, however, it can be seen that this aspect of the invention significantly mitigates the difficulties left unresolved in the art.
In particular, because it can be both supported and restrained vertically by the pin-and-aperture combinations, the novel codestrip can be mounted with much lower tension than earlier strips. The vertical support and restraint can be used to prevent the strip from bouncing downward out of the encoder groove—or upward and striking the end of the groove—particularly near the middle of the span, as well as from sagging and rotating.
Nevertheless, since it is not to be fastened to its supports at the several pins, this codestrip is quickly and easily installed and replaced. It is also subject to substantially common tension all along its length and so behaves in a consistent fashion longitudinally.
Although this aspect of the invention in its broad form thus represents a significant advance in the art, it is preferably practiced in conjunction with certain other features or characteristics that further enhance enjoyment of overall benefits.
For example, it is preferred that the ends of the elongated member are for fastening to the mounting means, to secure and tension the elongated member. In this arrangement, at least one of the spaced apertures is spaced distinctly away from the fastening ends of the elongated member.
Preferably the codestrip is a composite strip comprising a transparent member secured to a strength member. Also preferably the spaced apertures are shaped to constrain the elongated member with respect to exclusively one dimension; preferably they are slot-shaped (this allows for thermal expansion and contraction independently of the pins and mount).
Preferably the elongated member exceeds approximately one meter (roughly forty inches) in length. Still more preferably the elongated member exceeds approximately 1.25 meter (approximately fifty inches) in length.
The member is capable of use in spans of 1.5 and 1.75 meters (sixty and seventy) inches and longer, in which its use is still more preferable. The present novel codestrip escapes from the previously undesirable relationship between tension or positioning problems, on the one hand, and length on the other hand.
Preferably the apertures are spaced to facilitate cutting elongated members in several different sizes from common, preapertured stock. More specifically, it is preferred that they be spaced at approximately thirty centimeters (11¾ inches) on centers to facilitate cutting spans of approximately 91½, 106½, 152½ and 183 centimeters (thirty-six, forty-two, sixty and seventy-two inches) from common, preapertured stock.
Preferably at least one of the spaced apertures is positioned to prevent fundamental oscillation of the elongated member, due to environmental vibration, from moving the elongated member out of a specified operating position. Such positioning is especially effective in avoiding the vertical bouncing or sagging of previous codestrips, particularly in case of vibration from nearby equipment as mentioned earlier.
In preferred embodiments of a second of its major aspects, the invention is a printer for use in incremental printing. The printer has an encoding system, and includes an elongated encoder strip defining encoder indicia—and having spaced apertures formed in the encoder strip.
In preferred embodiments of a second of its major aspects, the invention is a printer for use in incremental printing. The printer has an encoding system, and includes an elongated encoder strip defining encoder indicia—and having spaced apertures formed in the encoder strip.
The printer also includes some means for mounting the encoder strip. For purposes of generality and breadth in discussing the invention, these means will be called simply the “mounting means”.
The mounting means in turn include some means for nonclamping protrusion through the spaced apertures of the encoder strip to support and align the encoder strip. Again for breadth and generality these means will be called the “nonclamping protrusion means”.
The nonclamping protrusion means include a series of spaced pins. Also part of the printer are some means for responding to the encoder indicia (the “responding means”) to control printing.
The foregoing may constitute a description or definition of the second facet of the invention in its broadest or most general form. Even in this general form, however, it can be seen that this aspect of the invention too significantly mitigates the difficulties left unresolved in the art.
In particular, the incremental printer of this second aspect of the invention is capable of forming drawings or photographic-quality pictures on paper of virtually unlimited width, since the printer itself can now be manufactured essentially as wide as desired.
Although this second aspect of the invention in its broad form thus represents a significant advance in the the “supporting and tensioning means” or in shorthand form the “end-supporting means”. In this case, at least one of the spaced pins is spaced distinctly away from the end-supporting means.
Another preference, particularly if the printer includes a scanning printhead carriage that moves substantially parallel to the encoder strip, is that the printer further have a sensor disposed adjacent to the encoder strip and carried on the scanning printhead carriage. Here it is preferable that the previously mentioned responding means include means for developing signals representative of position and velocity of the sensor and carriage relative to the encoder strip. These signal-developing means are responsive to the sensor.
Yet another preference is that the printer include printheads carried on the carriage and forming colorant patterns on the printing medium—to construct an image on the medium—and a printing-medium advance mechanism providing relative motion, perpendicular to the scanning printhead carriage, between the carriage and the printing medium. In this case the responding means further include a digital processor to coordinate the printheads and the advance mechanism in forming the image. The processor is responsive to the position- and velocity-representative signals.
In this novel printer, not only the required tension but also the scale-to-sensor dimension stack is essentially independent of codestrip length. The tension need only be high enough to hold the vertical positioning of the strip within a rather tight specification over the relatively short distance between two adjacent pins—a very easy task.
With this condition specified, that severe specification is the only number in the stack that importantly relates to sagging of the strip. That specification is substantially unrelated to the overall strip length.
In preferred embodiments of a third of its basic aspects or facets, the invention is a method for preparing and using an encoder strip, for use in incremental printing. The strip itself includes a thin, narrow, elongated member.
The method includes the steps of mounting the strip in tension with respect to its elongated dimension; and constraining the strip at multiple points spaced apart along its elongated dimension, for alignment with respect to its narrow dimension. The method also includes the step of leaving the strip substantially unconstrained with respect to its thin dimension; this last step, however, is not applied with respect to the ends of the strip, where in fact the strip is constrained with respect to its thin dimension.
Again this aspect of the invention, even as couched in these broad terms, significantly advances the art of incremental printing. This is so because, by the steps stated, the method establishes an encoding function that is essentially immune to displacement of the codestrip entirely out of operating position in its encoder, and also to lesser displacements sufficient to throw off the automatic counting of encoder indicia. Yet this method maintains uniform tension along the codestrip span, allows for natural thermal response, and leaves the strip sufficiently independent of its mounts for very easy installation, disassembly and reassembly.
Nevertheless it is preferable to use this novel method in conjunction with certain further features or characteristics that additionally enhance enjoyment of the benefits of the invention. For example, preferably the constraining step includes providing spaced-apart restraints for the strip, along the elongated dimension; and the mounting step comprises disposing the strip to engage the spaced-apart restraints.
Another preference is that the constraining step include providing apertures in the strip, spaced apart along the elongated dimension; and providing pins to protrude through the apertures without fastening the strip to the pins. In this case certain further preferences apply, particularly if the method is for use with an encoder sensor that undergoes relative motion with respect to the strip, along the elongated dimension.
Among those preferences are these three: the mounting step comprises disposing the strip in a functional positioning with respect to the sensor; in operation the strip is subject to vibration that tends to disturb that functional positioning; and the pins maintain the functional positioning. In this case, particularly if the system includes an encoder sensor that has a channel for the strip, it is yet further preferable that the mounting step include disposing the strip to extend through the channel in the sensor; and that the pins prevent the strip from leaving the channel.
All of the foregoing operational principles and advantages of the present invention will be more fully appreciated upon consideration of the following detailed description, with reference to the appended drawings, of which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric or perspective view, taken from right rear and above, of a carriage and carriage-drive mechanism according to a preferred embodiment of apparatus aspects of the present invention;
FIG. 2 is a like view, but very greatly enlarged, of locating pins and slots at the exemplary five positions marked “LPS” in FIG. 1;
FIG. 3 is a view like FIG. 1 but enlarged and taken along the lines 3 — 3 (i. e. from left rear and above) in FIG. 1;
FIG. 4 is a left end elevation, taken along the lines 4 — 4 in FIG. 1;
FIG. 5 is a right end elevation, taken along the lines 5 — 5 in FIG. 1;
FIG. 6 is an isometric or perspective exterior view of a large-format printer-plotter which is a preferred embodiment of the present invention, and which includes mechanisms closely similar to those of FIGS. 1 through 5;
FIG. 7 is a view like FIG. 1 but of the FIG. 6 machine and taken from front above left;
FIG. 8 is a like view of a printing-medium advance mechanism which is mounted within the case or cover of the FIG. 6 device, in association with the carriage as indicated in the broken line in FIG. 8;
FIG. 9 is a like but more-detailed view of the FIG. 7 carriage, showing the printheads or pens which it carries;
FIG. 10 is a bottom plan of the printheads or pens, showing their nozzle arrays;
FIG. 11 is a detail view like FIG. 1 but enlarged and showing the region in the sight marked 11 — 11 in FIG. 1;
FIG. 12 is a view like FIG. 4 but enlarged and showing the region within the sight marked 12 — 12 in FIG. 4;
FIG. 13 is a conceptual block diagram of the printers of FIGS. through 12 ; and
FIG. 14 is a flow chart representing a preferred form of method aspects of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
1. Encoder Strip with Support and Alignment
a. Pin support and guidance—Preferred embodiments of the invention provide a novel way to hold and reference the encoder strip 33 (FIG. 1 ). The new system is remarkably very simple and elegant.
As taught in the Armiñana document mentioned earlier, the strip 33 is made up of a metal strength member 33 m (FIG. 3) and a plastic scale 33 p. Also as explained by Armiñana the plastic piece 33 p has the function of guarding the fine metal edges of the metal member 33 m.
Mounted along the scan-axis beam 38 , spaced longitudinally are locating pins 60 (FIG. 2 ). Correspondingly spaced slots 61 , 62 are punch-formed along the two-piece encoder strip 33 .
When all assembled to the beam 38 , the pins 60 and slots 61 , 62 form spaced-apart sets of locating pins and slots LPS. The strip 33 at assembly is tensioned from its ends as before but also positioned on the pins 60 —i. e. so that the pins 60 extend through the slots 61 , 62 in the strip 33 .
The plastic scale 33 p has alternating transparent and opaque portions forming graduations, as fully detailed Armiñana. This scale passes through a groove 133 g (FIGS. 5 and 12) in the sensor 133 . The sensor 133 has a light source at one side of the groove and a detector at the other.
The pins 60 prevent the previously troublesome vertical movement. They locate the strip 33 in a very accurate position for the sensor 133 to read the graduations.
More specifically, mounting holes 68 for the locating pins 60 are formed along the beam 38 . The pins 60 are inserted into the mounting holes 68 and extend from the beam 38 toward the position of the encoder strip 33 , 33 m, 33 p. A plastic spacer 66 stands off the strip 33 from the beam 38 , to the correct location within the sensor groove 133 g.
As formed in the metal portion 33 m of the strip 33 , the slots 61 (FIG. 2) are in a close clearance fit with the pins 60 . Ordinarily the exact clearance is not extremely critical since the strip 33 is under some tension and therefore tends to pull the slot edges of the thin metal strength member 33 m into position as required even in case of some very slight degree of interference fit.
As formed in the plastic scale 33 p, the slots 62 are larger than those in the strength member 33 m. The point is to ensure that the locating action, and any necessary straightening forces, bear upon the strength member 33 m, rather than the relatively compliant plastic scale 33 p.
A small area of the metal member 33 m thus is seen in the illustration, through the slot 62 serving as a window in the plastic scale 33 p. Slots 61 , 62 rather than circular holes are formed in the codestrip 33 to accommodate very slightly different thermal deformation behaviors of the strip 33 and beam 38 .
Preferably at least one set LPS of locating pins and mating slots is relatively near the center of the strip, longitudinally, so as to deter vibration in a fundamental mode. The concern is vibrational amplitude, not particular harmonics; therefore it has proven unnecessary to space the pins-and-slot sets LPS according to any special harmonic analysis.
This freedom is advantageously exploited to enable manufacture of the codestrips for different machine sizes from common stock. The pin mounting holes 68 and the slots 61 , 62 are accordingly spaced for manufacturing convenience at a uniform distance of approximately 30 cm on centers (11¾ inches). That spacing has been found to provide suitable clear lengths at the ends of the strip for mounting, in every machine size now contemplated.
Preferably one end 33 m ″ of the strength member 33 m is bolted 69 to a solid mount, and the other end 33 m ′ (FIGS. 3 and 4) clamped or bolted to a spring plate 63 —on the end bulkhead 65 —that provides a calibrated tension. A retaining pin 64 projects from the spring plate 63 , and positively locates that end 33 m ′ of the strength member longitudinally.
b. Tension—In current products, tension levels are similar to those in previous units. Much of the earlier design of the spring 63 is being reused; the tensioning holder is very rigid and can effectively resist the tension.
For future models with larger scan-axis dimensions it will not be necessary to increase the tension at all, because cause the encoder weight is supported by the pins. In smaller products—unless they are modified to incorporate the present invention—the strip weight must be compensated with tension, exerting relatively high force on the tensioned holder.
Thus for example in earlier designs the encoder-strip tension for a machine with printing area 91 cm (3 foot) wide the tension is 36 newtons—but for a machine with 137 cm (4½ foot) printing area, 5 newtons. With the current invention, the tension for the 91 cm machine can still be 36 N, and a 152 cm (5 foot) machine, too, is only 36 N.
Such low tension causes no problems. Nevertheless if desired the tension in both machine sizes could be reduced from 36 to, say, 25 N.
Perhaps most important in this regard, required tension is now independent of codestrip length. The tension need only be sufficient to maintain good vertical-positioning tolerance over the span between any two adjacent pins—i. e., only about 30 cm.
c. Straightness—The straightness of the current encoder is just the straightness of the pin locations on the rod beam. In the current best implementation it is less than ±0.15 mm. With no pins the natural deformation of the encoder is much greater, on the order of ±0.8 mm, and can vary with time, from lot to lot, etc.
d. Dimensional stack—As noted earlier, codestrip designs heretofore have suffered from an unduly long dimension stack. The present invention permits a major reduction in the stack, and makes the stack—like the tension—in essence independent of codestrip length.
Height variation in the encoder-strip scale is now only the tolerance for a short span of 30 cm between pins. That is determined by the codestrip properties and the tension—which as already noted has also been made independent of the strip length.
In consequence, tolerances of every related dimension can be smaller. A much more robust design has resulted.
e. Slot-and-threaded-support variant—In practice of the present invention, pressed-in pins are greatly preferred to screw-in elements such as studs and screws. With proper installation equipment, pins are much faster to install in the base.
Screw-in-elements, however, are entirely usable in place of pins, and may be substituted if desired for whatever reason. One possible situation in which screws or studs may be helpful is field retrofit of older machines.
As noted earlier, such products may be advantageously retrofitted with slot support according to the present invention. Retrofit is useful if operation is affected by nearby construction, passing trucks, railway or subway lines, heavy industry or buildings with active freight elevators and the like.
Trained field-service personnel using suitable special jigs or fixtures can drill and tap precisely positioned holes in the base. Studs or screws are then readily installed to support the codestrip.
f. Representative dimensions—The accompanying specifications are typical of a now-preferred embodiment. Except to the extent incorporated into the accompanying claims, they should be considered merely exemplary.
dimensions (mm)
slot
strip
overall strip
length on
portion
height
thickness
centers
diameter
metal
8
0.1
3
2.1
plastic
14
0.18
3
3.75
4A length
spacing
embed
project
tot.
diameter
pins
300
3
9
12
2
overall approx. width in FIGS. 4 & 5
carriage
250
g. Relationship to the prior art—The present invention enables strips with spans of 152 cm and 183 cm (five and six feet respectively) to be assembled into a large-format printer/plotter in a completely routine way. Yet it substantially eliminates previously pervasive failures in functional-vibration tests—near the middle of the strip as well as elsewhere.
Vibration-induced bad readings from the sensor, such as miscounting by one or more scale graduations, have become essentially historical phenomena. The strip never jumps out of the sensor groove and accordingly never threatens to drive into the end bulkheads or in any other way to damage nearby components.
No support ledge, “ceiling” element, or limiter is used. Tension in the strip is essentially as low as could be desired, substantially obviating safety concerns in this regard—as well as all potential for related deformations and calibration problems. It has not been necessary to strengthen the beam or any other part of the mechanism to achieve these goals.
No stiffening element or other attachment to the strip itself is used, and nothing is added to the strip or immediately next to it that might pose a risk of damage. No adhesive, screw or bolt is needed to fix the strip to the base; rather the pins are simply pressed into place, significantly restraining assembly cost.
Required tension is dramatically reduced. Perhaps more importantly, the tension is now substantially independent of the codestrip length.
The tension need only be sufficient to provide good straightness over the roughly 30 cm span between adjacent pins. The encoder dimension stack, too, is correspondingly reduced, and also essentially independent of the encoder-strip length.
Therefore the invention can be routinely incorporated into the present generation of 1½ to 2 m printers—and also into smaller systems, and even much larger systems, with equal ease. It can be implemented in a retrofit mode for smaller systems in problematic environments.
In other words, the present system not only resolves the problems described in the “BACKGROUND” section of this document for strips one to two meters long, but actually appears to remove the length barrier entirely. With the present invention, strips under modest tension can be supported with reliable orientation and positional stability at practically any length desired. The pin-located codestrip has resolved every aspect of the defiant, knotty problems detailed earlier.
2. Other Hardware Components
As noted earlier, the present invention is compatible equally well with the present generation of 1½ m and 2 m printer/plotters and earlier basic designs, some of which remain in production. This is emphasized by showing a different model, to illustrate general features of the preferred printer/plotter, from the unit appearing in FIGS. 1 through 5, and FIGS. 11 and 12.
Thus some preferred embodiments include a main case 1 (FIG. 6) with a window 2 , and a left-hand pod 3 that encloses one end of the chassis. Within that pod are carriage-support and -drive mechanics and one end of the printing-medium advance mechanism, as well as a pen-refill station containing supplemental ink cartridges.
The printer/plotter also includes a printing-medium roll cover 4 , and a receiving bin 5 for lengths or sheets of printing medium on which images have been formed, and which have been ejected from the machine. A bottom brace and storage shelf 6 spans the legs which support the two ends of the case 1 .
Just above the print-medium cover 4 is an entry slot 7 for receipt of continuous lengths of printing medium 4 . Also included are a lever 8 for control of the gripping of the print medium by the machine.
A front-panel display 11 and controls 12 are mounted in the skin of the right-hand pod 13 . That pod encloses the right end of the carriage mechanics and of the medium advance mechanism, and also a printhead cleaning station. Near the bottom of the right-hand pod for readiest access is a standby switch 14 .
Within the case 1 and pods 3 , 13 the carriage assembly 20 (FIG. 7) is driven in reciprocation by a motor 31 —along dual support and guide rails 32 , 34 —through the intermediary of a drive belt 35 . The motor 31 is under the control of signals 57 from a digital electronic microprocessor (essentially all of FIG. 13 except the print engine 50 ). In the block-diagrammatic showing, the carriage assembly 20 travels to the right 55 and left (not shown) while discharging ink 54 .
A very finely graduated encoder strip 33 is extended taut along the scanning path of the carriage assembly 20 , and read by an automatic optoelectronic sensor 133 , 233 to provide position and speed information 52 for the microprocessor. (In FIG. 13, signals in the print engine are flowing from left to right except the information 52 fed back from the encoder sensor 233 —as indicated by the associated leftward arrow.)
The codestrip 33 thus enables formation of color ink-drops at ultrahigh resolution (typically 24 pixels/mm) and precision, during scanning of the carriage assembly 20 in each direction.
A currently preferred location for the encoder strip 33 is near the rear of carrisge tray (remote from the space into which a user's hands are inserted for servicing of the pen refill cartridges). Immediately behind the pens is another advantageous position for the strip 36 (FIG. 3 ).
The encoder sensor 133 (for use with the encoder strip in its forward position 33 ) or 233 (for rearward position 36 ) is disposed with its optical beam passing through orifices or transport portions of a scale formed in the strip. A separate line sensor 37 (FIGS. 5, 7 and 8 ) also rides on the carriage 20 , for reading test patterns or other information from the printing medium.
A cylinder platen 41 (FIG. 8 )—driven by a motor 42 , worm 43 and worm gear 44 under control of signals 46 from the processor 15 —rotates under the carriage-assembly 20 scan track to drive sheets or lengths of printing medium 4 A in a medium-advance direction perpendicular to the scanning. Print medium 4 A is thereby drawn out of the print-medium roll cover 4 , passed under the pens on the carriage 20 to receive inkdrops 54 for formation of a desired image, and ejected into the print-medium bin 5 .
The carriage assembly 20 includes a previously mentioned rear tray 21 (FIG. 9) carrying various electronics. It also includes bays 22 for preferably four pens 23 - 26 holding ink of four different colors respectively—preferably cyan in the leftmost pen 23 , then magenta 24 , yellow 25 and black 26 .
In the illustrations of the current model (FIGS. 1 through 5 ), the pens are not shown installed. When in place they are under the cartridge retainer latch 67 and project downward slightly beyond the bottom of the line sensor 37 .
Each of the pens, particularly in a large-format printer/plotter as shown, preferably includes a respective ink-refill valve 27 . The pens, unlike those in earlier mixed-resolution printer systems, all are relatively long and all have nozzle spacing 29 (FIG. 10) equal to one-twelfth millimeter—along each of two parallel columns of nozzles. These two columns contain respectively the odd-numbered nozzles 1 to 299 , and even-numbered nozzles 2 to 300 .
The two columns, thus having a total of one hundred fifty nozzles each, are offset vertically by half the nozzle spacing, so that the effective pitch of each two-column nozzle array is approximately one-twenty-fourth millimeter. The natural resolution of the nozzle array in each pen is thereby made approximately twenty-four nozzles (yielding twenty-four pixels) per millimeter, or 600 per inch.
Preferably black (or other monochrome) and color are treated identically as to speed and most other parameters. In the preferred embodiment the number of printhead nozzles used is always two hundred forty, out of the three hundred nozzles (FIG. 10) in the pens.
This arrangement allows for software/firmware adjustment of the effective firing height of the pen over a range of ±30 nozzles, at approximately 24 nozzles/mm, or ±30/24=±1¼ mm. This adjustment is achieved without any mechanical motion of the pen along the print-medium advance direction.
Alignment of the pens can be automatically checked and corrected through use of the extra nozzles. As will be understood, the invention is amenable to use with a very great variety in the number of nozzles actually operated.
3. Microprocessor Hardware
Data-processing arrangements for the present invention can take any of a great variety of forms. To begin with, image-processing and printing-control tasks 332 , 40 can be shared (FIG. 13) among one or more processors in each of the printer 320 and an associated computer and/or raster image processor 30 .
A raster image processor (“RIP”) is nowadays often used to supplement or supplant the role of a computer or printer—or both—in the specialized and extremely processing-intensive work of preparing image data files for use, thereby releasing the printer and computer for other duties. Processors in a computer or RIP typically operate a program known as a “printer driver”.
These several processors may or may not include general-purpose multitasking digital electronic microprocessors (usually found in the computer 30 ) which run software, or general-purpose dedicated processors (usually found in the printer 320 ) which run firmware, or application-specific integrated circuits (ASICs, also usually in the printer). As is well-understood nowadays, the specific distribution of the tasks of the present invention among all such devices, and still others not mentioned and perhaps not yet known, is primarily a matter of convenience and econoics.
On the other hand, sharing is not required. If preferred the system may be designed and constructed for performance of all data processing in one or another of the FIG. 13 modules—in particular, for example, the printer 320 .
Regardless of the distributive specifics, the overall system typically includes a memory 232 m for holding color-corrected image data. These data may be developed in the computer or raster image processor, for example with specific artistic input by an operator, or may be received from an external source.
Ordinarily the input data proceed from image memory 232 m to an image-processing stage 332 that includes some form of program memory 333 —whether card memory or hard drive and RAM, or ROM or EPROM, or ASIC structures. The memory 333 provides instructions 334 , 336 for automatic operation of rendition 335 and printmasking 337 .
Image data cascades through these latter two stages 335 , 337 in turn, resulting in new data 338 specifying the colorants to be deposited in each pixel, in each pass of the printhead carriage 20 over the printing medium 41 . It remains for these data to be interpreted to form:
actual printhead-actuating signals 53 (for causing precisely timed and precisely energized ink ejection or other colorant deposition 54 ),
actual carriage-drive signals 57 (for operating a carriage-drive motor 35 that produces properly timed motion 55 of the printhead carriage across the printing medium), and
actual print-medium-advance signals 46 (for energizing a medium-advance motor 42 that similarly produces suitably timed motion of the print-medium platen 43 and thereby the medium 41 ).
Such interpretation is performed in the printing control module 40 . In addition the printing control module 40 may typically be assigned the tasks of receiving and intepreting the encoder signal 52 fed back from the encoder sensor 233 .
The printing-control stage 40 necessarily contains electronics and program instructions for interpreting the colorant-per-pixel-per-pass information 338 . Most of this electronics and programming is conventional, and represented in the drawing merely as a block 81 for driving the carriage and pen. That block in fact may be regarded as providing essentially all of the conventional operations of the printing control stage 40 .
4. Method
As suggested in FIG. 14, which will be self explanatory to people skilled in this field, method aspects of the present may be conceptualized as having two main steps. One of these is functional mounting 201 of the codestrip through the sensor groove, in tension.
The other is constraint 202 of the strip at multiple longitudinally spaced points for transverse alignment—i. e., in the previous illustrations, alignment vertically. In some sense perhaps a third major step is the result, namely stable operation 208 of the encoder sensor system.
For preferred embodiments, in the first step 201 the strip is mounted in functional positioning with respect to sensor. The second step 202 includes provision 203 of longitudinally spaced restraints.
Although disposition 206 of the strip to engage those restraints could be regarded as part of the constraint-providing step 202 , it is perhaps more logical—or at least equally so—to consider that disposition part of the mounting step 201 . Therefore in FIG. 14 (note dashed arrow) and certain of the appended claims, disposition of the strip to engage the restraints is conceptualized as part of or associated with the mounting step 201 .
The restraint provision 203 may be seen as further subdivided to include provision 204 of apertures in the strip, and provision 205 of pins to protrude through the apertures—without fastening of the strip to the pins.
Another significant preference is a step of omission, namely refraining 207 from acting to constrain the encoder strip with respect to its thin dimension. This step refers only to constraint at the locating pins, and thus is not absolute: at both its ends, the strip is constrained in that direction.
The above disclosure is intended as merely exemplary, and not to limit the scope of the invention—which is to be determined by reference to the appended claims. | Spaced pins support and align the strip. Apertures in the strip engage the pins with no fastening. The strip—best a transparent member and glued strength member—is end-mounted and -tensioned. Ideally the apertures are slots to constrain the strip as to only one dimension, and spaced (ideally about 30 cm on centers) to facilitate cutting various-size strips (e. g. for spans of roughly 91½, 106½, 152½ and 183 cm) from common, preapertured stock. The strip is longer than a meter; the invention is progressively more valuable for 1¼ m or longer strips. At least one pin is placed to keep fundamental oscillation of the strip, due to environmental vibration, from moving the strip out of position. The invention can take the form of the strip only, for use with the pins; or a printer with encoding system having the strip and pins—and a sensor responsive to the encoder to control printing; or a method of preparing a system for use. The pins prevent the strip from leaving the sensor and permit use of very low tension—only that needed to hold up the strip, within its vertical-alignment tolerance, over a short span between pins. The tension, and thereby the vertical-dimension stack from encoder scale to sensor, are thus made virtually independent of encoder-strip length. Such a printer ideally has a printhead carriage that scans parallel to the strip; the sensor (adjacent to the strip and carried on the carriage) develops signals representing position and velocity of the sensor and carriage relative to the strip. Printheads on the carriage form color marks to construct an image on a print medium. A medium-advance mechanism provides relative motion between carriage and medium. A processor responds to the position/velocity signals, and coordinates the printheads and advance mechanism to form the image. | 1 |
FIELD OF THE INVENTION
[0001] This invention relates to the field of light source used in illumination and display, and in particular, it relates to projection system, light source system and light source assembly.
DESCRIPTION OF THE RELATED ART
[0002] Currently, projectors are widely used in various applications, including playing movies, meeting and public events, etc. Phosphor color wheels are often used as the light source of projectors for providing a color light sequence. In such a device, different segments of the phosphor color wheel are alternately and periodically provided in the propagation path of the excitation light, on which the phosphor material coated are excited by the excitation light in order to generate color fluorescent light. However, because the spectral range of the fluorescent light generated by the phosphor material is wide, the color purity of the fluorescent light is poor, which result in an insufficient color gamut of the light source. In this case, color filters are needed to filter the fluorescent light, so that the color purity of the fluorescent light can be improved. However, because the spectral ranges of different colored fluorescent light are partly overlapped, they cannot be filter using a same color filter, so that different colored fluorescent light needs different color filter. In a conventional device, a color filter wheel composed of different color filters is provided in the entrance of the light homogenization rob, and a driving device of the color filter wheel and a driving device the phosphor color wheel are synchronized by electronic circuits. The above method has the following disadvantages: the structure is complex, it is difficult to achieve, and the synchronization effect is poor.
[0003] As the projector industry is increasingly competitive, manufacturers have to improve the quality of the projector to enhance their competitiveness. The inventors of the present invention in the process of actively seeking to improve the quality of the projector found that: in the prior art, the synchronization architecture of the phosphor color wheel and the color filter wheel of the projector light source has the technical problem: the structure is complex, it is difficult to achieve, and the synchronization effect is poor.
[0004] So, a projection system, a light source system and the light source devices are needed to solve the above technical problem existing in the synchronization architecture of the phosphor color wheel and the color filter wheel of the projector light source in the prior art.
SUMMARY OF THE INVENTION
[0005] The present invention seeks to solve the problem by providing a projection system, a light source system and light source assembly to simplify the synchronization architecture of the wavelength conversion device and the color filtering device, and improve the synchronization effect.
[0006] To solve the above problem, the present invention adopts a technical solution: providing a light source system, which includes an excitation light source, a wavelength conversion device, a color filter device, a driving device and a first optical assembly. The excitation light source is for generating an excitation light. The wavelength conversion device includes at least one wavelength conversion area. The color filter device is fixed with respected to the wavelength conversion device, and includes at least one color filter area. The driving device is for driving the color filter device and the wavelength conversion device and makes them move synchronously. The wavelength conversion areas are provided in the propagation path of the excitation light periodically in order to convert the excitation light into converted light. The first optical assembly is used to guide the converted light to the first color filter area, and the first color filter area filters the converted light to improve its color purity.
[0007] In some embodiments, the wavelength conversion device and the color filter device are two ring structures fixed coaxially.
[0008] In some embodiments, the driving device is a rotation device with a rotating shaft, and the two ring structures are coaxially fixed to the rotating shaft.
[0009] In some embodiments, the wavelength conversion area and the first color filter area are located at 180-degree angle from each other with respect to a centre of the two ring structures. A light spot formed by the excitation light on the wavelength conversion device and a light spot formed by the converted light on the color filter device after being directed by the first optical assembly are located at 180-degree angle from each other with respect to the center of the two ring structures.
[0010] In some embodiments, the wavelength conversion area and the first color filter area are located at 0-degree angle from each other with respect to a center of the two ring structures. A light spot formed by the excitation light on the wavelength conversion device and a light spot formed by the converted light on the color filter device after being directed by the first optical assembly are located at 0-degree angle from each other with respect to the center of the two ring structures.
[0011] In some embodiments, the wavelength conversion device and the color filter device are spaced apart along an axial direction of the driving device; the first optical assembly includes at least one light collecting device disposed between the wavelength conversion device and the color filter device; and the light collecting device collects the converted light so that an energy of the converted light incident on the color filter device with less than or equal to 60-degree incident angles is more than 90% of a total energy of the converted light.
[0012] In some embodiments, the wavelength conversion area reflects the converted light so that a direction of the converted light emitted from the wavelength conversion area is opposite to a direction of the excitation light incident on the wavelength conversion area.
[0013] In some embodiments, the wavelength conversion area transmits the converted light so that a direction of the converted light emitted from the wavelength conversion area is the same as a direction of the excitation light incident on the wavelength conversion area.
[0014] In some embodiments, the first optical assembly includes at least one light collecting device which collects the converted light so that an energy of the converted light incident on the color filter device with less than or equal to 60-degree incident angles is more than 90% of a total energy of the converted light.
[0015] In some embodiments, the first optical assembly includes at least one reflecting device which reflects the converted light to change a propagation direction of the converted light, and the reflecting device is a planar reflecting device or a semi-ellipsoidal or hemispherical reflecting device with a reflecting surface facing inside.
[0016] In some embodiments, the planar reflecting device includes a dichroic mirror or a reflecting mirror.
[0017] In some embodiments, the semi-ellipsoidal or hemispherical reflecting device with the reflecting surface facing inside is provided with a light entrance port through which the excitation light is incident on the wavelength conversion device.
[0018] In some embodiments, the wavelength conversion device further includes a first light transmission area which is periodically disposed in the propagation path of the excitation light under the driving of the driving device and which transmits the excitation light.
[0019] In some embodiments, the system further includes a second optical assembly which combines the excitation light transmitted by the first light transmission area and the converted light filtered by the first color filter area.
[0020] In some embodiments, the color filter device includes a second light transmission area or a second color filter area, and the first optical assembly guides the excitation light transmitted by the first light transmission area, along the same propagation path of the converted light, to the second light transmission area or the second color filter area to be transmitted or filtered.
[0021] In some embodiments, the system further includes an illumination light source which generates an illumination light; the wavelength conversion device further includes a first light transmission area which is periodically disposed in a propagation path of the illumination light under the driving of the driving device, the first light transmission area transmitting the illumination light; the color filter device further includes a second light transmission area or a second color filter area; and the first optical assembly guides the illumination light transmitted by the first light transmission area, along the same propagation path of the converted light, to the second light transmission area or the second color filter area to be transmitted or filtered.
[0022] In some embodiments, the system further includes: an illumination light source generating an illumination light, and a second optical assembly which combines the illumination light and the converted light filtered by the first color filter area into one beam of light.
[0023] In some embodiments, the wavelength conversion device is a cylindrical structure and the color filter device is a ring structure which is coaxial fixed with the cylindrical structure so that they rotate coaxially and synchronously under the driving of the driving device.
[0024] In some embodiments, the wavelength conversion area is provided on an outer surface of a sidewall of the cylindrical structure and reflects the converted light, and the first color filter area is provided on the ring structure located outside of the cylindrical structure to receive the converted light.
[0025] In some embodiments, the wavelength conversion device and the color filter device are two cylindrical structures coaxially fixed and nested within each other to rotate coaxially and synchronously under the driving of the driving device; the wavelength conversion area and the first color filter area are respectively provided on sidewalls of the two cylindrical structure; and the converted light is transmitted by the wavelength conversion area and incident on the first color filter area.
[0026] In some embodiments, the wavelength conversion device and the color filter device are two strip structures adjoined side by side, on which the wavelength conversion area and the first color filter area are provided side by side, the two strip structures move in an oscillating linear translational motion under the driving of the driving device.
[0027] The present invention also provides a source module, which includes: wavelength conversion device including at least one wavelength conversion area, and a color filter device fixed with respected to the wavelength conversion device and including at least one color filter, where the wavelength conversion area and the color filter area move synchronously under the driving of a driving device.
[0028] In some embodiments, the wavelength conversion device and the color filter device are two ring structures fixed coaxially.
[0029] In some embodiments, the wavelength conversion device is a cylindrical structure and the color filter device is a ring structure which is fixed coaxially with the cylindrical structure.
[0030] In some embodiments, the wavelength conversion area is provided on an outer surface of a sidewall of the cylindrical structure, and the color filter area is provided on the ring structure located outside of the cylindrical structure.
[0031] In some embodiments, the wavelength conversion device and the color filter device are two cylindrical structures which are fixed coaxially and nested within each other, and the wavelength conversion area and the color filter area are provided on sidewalls of the two cylindrical structures respectively.
[0032] In some embodiments, the wavelength conversion device and the color filter device are two strip structures adjoined side by side, on which the wavelength conversion area and the color filter area are provided side by side.
[0033] The present invention also provides a projection system, which includes a light source system described above.
[0034] The advantage of the present invention is: different from the prior art, in the projection system, the light source system and the light source assembly of the present invention, the color filter device and the wavelength conversion device are fixed with each other, and driven by the same driving device, which can bring the advantages: the structure is simple, it is easy to implement, and the synchronization effect is excellent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 illustrates the structure of a light source system according to a first embodiment of the present invention.
[0036] FIG. 2 is a front view of the wavelength conversion device and the color filter device of the light source system shown in FIG. 1 .
[0037] FIG. 3 illustrates the structure of a light source system according to a second embodiment of the present invention.
[0038] FIG. 4 is a front view of the wavelength conversion device and the color filter device of the light source system shown in FIG. 3 .
[0039] FIG. 5 illustrates the structure of a light source system according to a third embodiment of the present invention.
[0040] FIG. 6 is a front view of the wavelength conversion device and the color filter device of the light source system shown in FIG. 5 .
[0041] FIG. 7 illustrates the structure of a light source system according to a fourth embodiment of the present invention.
[0042] FIG. 8 illustrates the structure of a light source system according to a fifth embodiment of the present invention.
[0043] FIG. 9 illustrates the structure of a light source system according to a sixth embodiment of the present invention.
[0044] FIG. 10 illustrates the structure of a light source system according to a seventh embodiment of the present invention.
[0045] FIG. 11 illustrates the structure of a light source system according to an eighth embodiment of the present invention.
[0046] FIG. 12 illustrates the structure of a light source system according to a ninth embodiment of the present invention.
[0047] FIG. 13 illustrates the structure of a light source system according to a tenth embodiment of the present invention.
[0048] FIG. 14 illustrates the structure of a light source system according to an eleventh embodiment of the present invention.
[0049] FIG. 15 illustrates the structure of a light source system according to a twelfth embodiment of the present invention.
[0050] FIG. 16 is a front view of the wavelength conversion device and the color filter device of the light source system shown in FIG. 15 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0051] Referring to FIG. 1 and FIG. 2 , FIG. 1 illustrates the structure of a light source system according to a first embodiment of the present invention, and FIG. 2 is a front view of the wavelength conversion device and the color filter device in the light source system shown in FIG. 1 . As show in FIG. 1 , the light source system in this embodiment mainly includes an excitation light source 101 , a dichroic mirror 102 , a mirror 104 , lenses 103 and 105 , a wavelength conversion device 106 , a color filter device 107 , a driving device 108 and a light homogenization device 109 .
[0052] The excitation light source 101 is for generating an excitation light. In this embodiment, the excitation light source 101 is ultraviolet or near-ultraviolet laser diode or ultraviolet or near-ultraviolet light emitting diode, in order to generate ultraviolet or near-ultraviolet excitation light.
[0053] As show in FIG. 2 , the wavelength conversion device 106 has a ring structure, including at least one wavelength conversion area. In the present embodiment, the wavelength conversion device 106 includes a red wavelength conversion area, a green wavelength conversion area, a blue wavelength conversion area and a yellow wavelength conversion area, which are provided in circumferential subsections of the ring structure. Different wavelength conversion materials are coated on the wavelength conversion areas respectively (for example, phosphor materials or nanomaterials). The wavelength conversion materials can convert the ultraviolet or near-ultraviolet excitation light that illuminate them into the converted light of corresponding color. Specifically, the red wavelength conversion area converts the ultraviolet or near-ultraviolet excitation light incident to it into red converted light, the green wavelength conversion area converts the ultraviolet or near-ultraviolet excitation light incident to it into green converted light, the blue wavelength conversion area converts the ultraviolet or near-ultraviolet excitation light incident to it into blue converted light, and the yellow wavelength conversion area converts the ultraviolet or near-ultraviolet excitation light incident to it into yellow converted light. In the present embodiment, a reflective substrate is provided under the wavelength conversion materials in order to reflect the converted light generated by the wavelength conversion materials, so that the exit direction of the converted light output from the wavelength conversion area is opposite to the incident direction of the excitation light incident to the wavelength conversion area.
[0054] As show in FIG. 2 , the color filter device 107 has a ring structure, coaxially fixed with the wavelength conversion device 106 , and disposed outside the ring of the wavelength conversion device 106 . In other embodiments, the color filter device 107 can also be disposed inside the ring of the wavelength conversion device 106 . The color filter device 107 includes at least one color filter area. In the present embodiment, the color filter device 107 includes a red filter area, a green filter area, a blue filter area and a yellow filter area, which are provided in circumferential subsections of the ring structure. Each color filter area corresponds to a wavelength conversion area of the wavelength conversion device 106 . In the present embodiment, the color filter area and the wavelength conversion area of the same color are set at a 180-degree angle from each other with respect to the center of the ring structures of the wavelength conversion device 106 and the color filter device 107 . The different color filter areas have different spectral responses, and filter the converted light of corresponding colors, in order to improve the color purity of the converted lights.
[0055] Of course, the color filter area and the wavelength conversion area of the same color can be set at angles with respect to the center of the ring structures of the wavelength conversion device 106 and the color filter device 107 .
[0056] As show in FIG. 1 , the driving device 108 is a rotary device which has a rotary shaft 1081 , for example, a rotary motor. The wavelength conversion device 106 and the color filter device 107 are coaxially fixed on the rotary shaft 1081 , and rotate synchronously under the driving of the rotary shaft 1081 .
[0057] In the working process of the light source system 100 shown in FIG. 1 , the ultraviolet or near-ultraviolet excitation light generated by the excitation light source 101 is transmitted through the dichroic mirror 102 , converged by the lens 103 , incident on the wavelength conversion device 106 , to form a light spot 101 A on the wavelength conversion device 106 as shown in FIG. 2 . The wavelength conversion device 106 and the color filter device 107 rotate synchronously under the driving of the driving device 108 , so that the wavelength conversion areas of the wavelength conversion device 106 and the color filter areas of the color filter device 107 can rotate synchronously. When the wavelength conversion device 106 and the color filter device 107 rotate, the wavelength conversion areas of the wavelength conversion device 106 are disposed in the propagation path of the ultraviolet or near-ultraviolet excitation light generated by the excitation light source 101 sequentially and periodically, so that the ultraviolet or near-ultraviolet excitation light can be converted into the converted light of different colors sequentially by the respective wavelength conversion areas. The converted lights of different colors are further reflected by the wavelength conversion areas respectively, guided by the first optical assembly which is composed of lenses 103 and 105 , dichroic mirror 102 , and reflecting mirror 104 , then incident on the light filer device 107 and form a light spot 101 B as shown in FIG. 2 .
[0058] In the first optical assembly, the lenses 103 and 105 are used for collecting and condensing the converted light respectively, so that the divergence angle of the converted light can be decreased. The dichroic mirror 102 and the reflecting mirror 104 are used for reflecting the converted light, so that the propagation direction of the converted light can be changed. In the present embodiment, the dichroic mirror 102 and the reflecting mirror 104 are set at a 90-degree angle to each other and 45-degree angle to the incident direction of the converted light. In the present embodiment, because of the reflection of the dichroic mirror 102 and the reflecting mirror 104 , the propagation direction of the converted light is shifted by a predetermined distance and inverted by 180-degree angle, and the light spot 101 A is set at 180-degree angle to the light spot 101 B with respect to the center of the ring structures of the wavelength conversion device 106 and the color filter device 107 .
[0059] In this case, the wavelength conversion device 106 is fixed with respect to the color filter device 107 , and the wavelength conversion areas of the wavelength conversion device 106 and the color filter areas of the color filter device 107 with the same colors are set at 180-degree angle from each other with respect to the center of the ring structures of the wavelength conversion device 106 and the color filter device 107 and rotate synchronously, so that the converted light of different colors generated by the wavelength conversion areas of the wavelength conversion device 106 are incident on the color filter areas of the color filter device 107 with the same colors after they pass through the dichroic mirror 102 and the reflecting mirror 104 , and the color purity is improved by the color filter area with the same color filtering the light. After filtering by the color filter area of the color filter device 107 , the converted light then is incident on the light homogenization device 109 to be made uniform.
[0060] In the light source system 100 of the present embodiment, the wavelength conversion device 106 and the color filter device 107 are fixed with respect to each other and driven synchronously by the same driving device. At the same time, the wavelength conversion area and the color filter area of the same color are synchronized by the first optical assembly. It has the advantages that: the structure is simple, it is easy to implement and the synchronization effect is excellent. In addition, each element of the first optical assembly is stationary with respect to the excitation light source, and do not rotate with the rotation of the wavelength conversion device 106 and the color filter device 107 , so the optical stability is improved.
[0061] Further, since the converted light generated through wavelength conversion generally has an approximately Lambertian distribution, if the converted light is directly incident on the color filter area, the incident angle will be distributed in the range of 0 degree to 90 degrees. However, the transmittance of the color filter area will shift with the increase of the incident angle, so in the present embodiment, the first optical assembly further includes a light convergence device (for example, a lens 105 ) to converge the converted light, which can decrease the incident angle of the converted light incidence on the color filter area and further improve the color filter effect. In a preferred embodiment, by adjusting the first optical assembly, the energy of the converted light that is incident on the light filter 107 with incident angles less than or equal to 60 degrees can be more than 90% of the total energy of the converted light. In the present embodiment, the dichroic mirror 102 and the reflecting mirror 104 can be replaced by other forms of planar reflecting device, and the lenses 103 and 105 can be replaced by other forms of optical devices. For example, the lens 105 may be replaced by various forms of light convergence devices like a solid or hollow tapered light guide, a lens or lens group, a hollow or solid composite light condenser, or a curved reflecting mirror, etc.
[0062] In addition, in the present embodiment, the wavelength conversion areas of the wavelength conversion device 106 can be a combination of one or more of the red wavelength conversion area, the green wavelength conversion area, the blue wavelength conversion area and the yellow wavelength conversion area, and the excitation light source can be another suitable light source. Alternatively, those skilled in the art can select the wavelength conversion area and the excitation light source with other colors as desired. In this case, the color filter areas of the color filter device 107 are configured according to the colors of the converted light generated by the wavelength conversion areas of the wavelength conversion device 106 , and the present invention shall not be limited to any specific arrangement.
[0063] Referring to in FIG. 3 and FIG. 4 , FIG. 3 is a schematic structural view of the second embodiment of the light source system of the present invention, and FIG. 4 is a front view of the wavelength conversion device and the color filter device of the light source system shown in FIG. 3 . The light source system 200 of the present embodiment and the light source system 100 as shown in FIG. 1 and FIG. 2 differ in that: the excitation light source 201 is a blue laser or blue light-emitting diode in order to generate a blue excitation light. As show in FIG. 4 , in the present embodiment, besides of a red wavelength conversion area, a yellow wavelength conversion area and a green wavelength conversion area, the wavelength conversion device 206 further includes a blue light transmission area. The color filter device 207 includes a red color filter area, a yellow color filter area and a green color filter area. In the present embodiment, the area of the color filter device 207 which is corresponding to the blue light transmission area of the wavelength conversion device 206 is not required to have a particular optical property, and it can be provided as a counterweight balance area for rotation balance, so it should have the same or similar weight as the other color filter areas. In the present embodiment, the wavelength conversion device 206 and the color filter device 207 rotate synchronously under the driving of the driving device 208 , so that the wavelength conversion areas and the blue light transmission area of the wavelength conversion device 206 are sequentially and periodically disposed in the propagation path of the blue excitation light generated by the excitation light source 201 . The wavelength conversion areas convert the blue excitation light incident on them into the converted light of corresponding colors and reflect them, and the blue light transmission area transmits the blue excitation light incident on it. The blue light transmission area can be provided with appropriate scattering materials to destroy the collimation of the blue excitation light. The converted light reflected by the wavelength conversion device 206 is guided by the first optical assembly comprised of lenses 203 and 205 , dichroic mirror 202 and reflecting mirror 204 and incident on the color filter area of corresponding color on the color filter device 207 , so that it is filtered by the color filter area to improve its color purity. The blue excitation light transmitted by the wavelength conversion device 206 is guided by the second optical assembly comprised of lenses 210 and 213 , reflecting mirror 211 and dichroic mirror 212 , and is combined with the converted light filtered by the color filter device 207 into one light beam, which is incident on the light homogenization device 209 to be made uniform.
[0064] Of the second optical assembly, the lenses 210 and 213 are used for collecting and converging the blue excitation light transmitted by the wavelength conversion device 206 , and the reflecting mirror 211 and the dichroic mirror 212 are used to reflect the blue excitation light transmitted by the wavelength conversion device 206 to change its propagation path. In the present embodiment, the reflecting mirror 211 and the dichroic mirror 212 are arranged in parallel with each other and they are set at 45 degrees to the incident direction of the blue excitation light so that the propagation direction of the blue excitation light is shifted by a predetermined distance but its propagation direction remains the same.
[0065] In the present embodiment, the blue excitation light generated by the excitation light source 201 is directly outputted as the blue light through transmission. In the present embodiment, the reflecting mirror 211 and the dichroic mirror 212 can be replaced by other forms of planar reflecting devices, and the lenses 210 and 213 can be replaced by other forms of optical devices. In addition, the above-described structure is also applicable to the light source system in which excitation light sources of other colors are used.
[0066] Referring to FIG. 5 and FIG. 6 , FIG. 5 is a schematic structural view of the light source system according to the third embodiment of the present invention, FIG. 6 is a front view of the wavelength conversion device and the color filter device of the light source system shown in FIG. 5 . The light source system 300 of the present embodiment and the light source system 200 shown in FIG. 3 and FIG. 4 differ in that: the light source 300 further includes. in addition to the excitation light source 301 , a red illumination light source 315 (for example, a red laser or a red light emitting diode) in order to generate a red illumination light. The red illumination light source 315 and the excitation light source 301 are respectively provided on the opposite sides of the wavelength conversion device 306 and the color filter device 307 . The red illumination light generated by the red illumination light source 315 passes through the lens 314 , the dichroic mirror 311 , the lens 310 to be incident on the wavelength conversion device 306 ; its incident direction is opposite to that of the excitation light generated by the excitation light source 301 .
[0067] In the present embodiment, the wavelength conversion device 306 includes a red light transmission area, a yellow wavelength conversion area, a green wavelength conversion area and a blue light transmission area. The color filter device 307 includes a red light transmission area, a yellow color filter area, a green color filter area and a counterweight balance area. In the present embodiment, under the driving of the driving device 308 , the wavelength conversion device 306 and the color filter device 307 rotate synchronously, so that the wavelength conversion areas, the red light transmission area and the blue light transmission area of the wavelength conversion device 306 are disposed in the propagation path of the blue excitation light generated by the excitation light source 301 and the red illumination light generated by the red illumination light source 315 sequentially and periodically. The various wavelength conversion areas convert the blue excitation light incident on them into the converted light of corresponding color and reflect it, the blue light transmission area transmits the blue excitation light incident on it, and the red light transmission area transmits the red illumination light incident on it. The blue light transmission area and the red light transmission area can be provided with appropriate scattering materials to destroy the collimation of the blue excitation light and the red illumination light. The converted light reflected by the wavelength conversion device 306 is guided by the first optical assembly comprised of lenses 303 and 305 , dichroic mirror 302 and reflecting mirror 304 and incident on the color filter area of corresponding color on the color filter device 307 , so that it is filtered by the color filter area to improve its color purity. The red illumination light transmitted by the wavelength conversion device 306 is guided by the first optical assembly comprised of lens 303 and 305 , dichroic mirror 302 and reflecting mirror 304 and incident to the red light transmission area of the color filter device 307 along the same propagation path of the converted light, then transmitted by the red light transmission area. The blue excitation light transmitted by the wavelength conversion device 306 is guided by the second optical assembly comprised of lenses 310 and 313 , dichroic mirrors 311 and 312 , and combined with the converted light filtered by the color filter device 307 and the red illumination light transmitted by the color filter device 307 into one light beam, which is incident on the light homogenization device 309 to be made uniform.
[0068] In a preferred embodiment, in order to ensure that the light homogenization device 309 receives only one color light at any time, the rotation position of the wavelength conversion device 306 is detected, and a synchronization signal is generated based on the detection. The excitation light source 301 and the red illumination light source 315 are turned on and off in a time-division manner according to the synchronization signal. Specifically, the red illumination light source 315 is turned on only when the red light transmission area is in the propagation path of the red illumination light generated by the red illumination light source 315 , and is turned off when the yellow wavelength conversion area, the green wavelength conversion area and the blue light transmission area are in the propagation path of the red illumination light. The excitation light source 301 is turned on only when the yellow wavelength conversion area, the green wavelength conversion area and the blue light transmission area are in the propagation path of the blue excitation light generated by the blue excitation light source, and is turned off when the red light transmission area is in the propagation path of the blue excitation light. In addition, in another preferred embodiment, a dichroic filter which transmits the red illumination light and reflects the blue excitation light can be provided in the red light transmission area, a reflecting mirror which reflects the red illumination light can be provided for the yellow wavelength conversion area and the green wavelength conversion area on the side facing the red illumination light source 315 , and a dichroic filter that transmits the blue excitation light and reflects the red illumination light can be provided in the blue light transmission area.
[0069] In the present embodiment, the red light outputted from the light source system 300 is supplied directly by the red illumination light source 315 , which can avoid the problem of low conversion efficiency of the red wavelength conversion material. Of course, when it needs to improve the color purity, the red light transmission area can be replaced by a red color filter area. In the present embodiment, those skilled in the art can use other illumination light source to generate the illumination light of other colors.
[0070] Referring to FIG. 7 , FIG. 7 is a schematic structural view of the light source system according to the fourth embodiment of the present invention. The light source system 400 of the present embodiment and the light source system 300 shown in FIG. 5 and FIG. 6 differ in that: the excitation light source 401 of the present embodiment is an ultraviolet or blue excitation light source. At the same time, the wavelength conversion device 406 in the present embodiment is provided with a yellow wavelength conversion area, a green wavelength conversion area and a red light transmission area. So the excitation light source 401 is only used to excite the yellow wavelength conversion area and the green wavelength conversion area to generate yellow converted light and green converted light. The light source system 400 in the present embodiment further includes a blue illumination light source 416 in addition to the excitation light source 401 and the red illumination light source 415 . The blue illumination light generated by the blue illumination light source 416 passes through the second optical assembly comprised of lenses 417 and 418 and dichroic mirror 419 , is combined with the converted light filtered by the color filter device 407 and the red illumination light transmitted or filtered by the color filter device 407 into one light beam, which is incident on the light homogenization device 409 to be made uniform. In the present embodiment, the excitation light source 401 , the red illumination light source 415 and the blue illumination light source 416 can also be turned on and off in a time-division manner similar to the third embodiment.
[0071] In the present embodiment, the red light outputted from the light source system 400 is supplied directly by the red illumination light source 415 and the blue light outputted from the light source system 400 is supplied directly by the blue illumination light source 416 , which can avoid the problem of low conversion efficiency of the wavelength conversion materials, and is more suitable for the display field.
[0072] Referring to FIG. 8 , FIG. 8 is a schematic structural view of the light source system according to the fifth embodiment of the present invention. The light source system 500 of the present embodiment and the light source system 100 shown in FIG. 1 and FIG. 2 differ in that: the wavelength conversion device 506 converts the excitation light generated by the excitation light source 501 into the converted light and transmits it. The converted light transmitted by the wavelength conversion device 506 is guided by the first optical assembly comprised of lenses 503 and 505 and reflecting mirror 502 and 504 and incident on the color filter area of the same color on the color filter device 507 . After filtering by the color filter area it is incident on the light homogenization device 509 .
[0073] In addition, the excitation light source 501 can also be a blue light source. A light transmission area can be further provided on the wavelength conversion device 506 . The light transmission area is provided in the propagation path of the excitation light generated by the excitation light source 501 periodically and transmits it. After being transmitted by the light transmission area, the excitation light passes through the first optical assembly comprised of lenses 503 and 505 and reflecting mirror 502 and 504 , and is guided to another light transmission area or color filter area on the color filter device 507 along the same propagation path as the converted light, to be is transmitted or filtered.
[0074] Referring to FIG. 9 , FIG. 9 is a schematic structural view of the light source system according to the sixth embodiment of the present invention. The light source system 600 of the present embodiment and the light source system 500 shown in FIG. 8 differ in that: the light source system 600 of the present embodiment further includes, in addition to the excitation light source 601 , a red illumination light source 615 in order to generate a red illumination light. The red illumination light source 615 and the excitation light source 601 are provided on the same side of the wavelength conversion device 606 and the color filter device 607 . The red illumination light generated by the red light illumination light source 615 is reflected by the dichroic mirror 613 , converged by the lens 611 , then incident on the wavelength conversion device 606 along the same direction as the excitation light generated by the excitation light source 601 . The excitation light generated by the excitation light source 601 is converted into the converted light by the wavelength conversion area of the wavelength conversion device 606 , and is transmitted by the wavelength conversion device 606 . The red illumination light generated by the red illumination light source 615 is transmitted directly by the red light transmission area of the wavelength conversion device 606 . The converted light transmitted by the wavelength conversion device 606 and the red illumination light is guided by the first optical assembly comprised of reflecting mirror 602 and 604 and lenses 603 and 605 , and incident on the color filter area and the red light transmission area of the color filter device 607 . The converted light filtered by the color filter area and the red illumination light transmitted by the red light transmission area are further incident on the light homogenization device 609 . In addition, the red light transmission area can be replaced by a red color filter area. In addition, the excitation light source 601 and the red illumination light source 615 in the present embodiment can also be turned on and off in a time-division manner similar to the third embodiment.
[0075] Referring to FIG. 10 , FIG. 10 is a schematic structural view of the light source system according to the seventh embodiment of the present invention. The light source system 700 of the present embodiment and the light source system 600 shown in FIG. 9 differ in that: the light source system 700 of the present embodiment further includes a blue illumination light source 716 in addition to the excitation light source 701 and the red illumination light source 715 . The blue illumination light generated by the blue illumination light source 716 passes through the second optical assembly comprised of lens 717 and dichroic mirror 718 , and is combined with the converted light filtered by the color filter device 707 and the red illumination light filtered or transmitted by the color filter device 707 into one light beam, which is incident on the light homogenization device 709 to be made uniform. In the present embodiment, the excitation light source 701 , the red illumination light source 715 and the blue illumination light source 716 can be turned on and off in a time-division manner similar to the third embodiment.
[0076] Referring to FIG. 11 , FIG. 11 is a schematic structural view of the light source system according to the eighth embodiment of the present invention. The light source system 800 of the present embodiment and the light source system 100 shown in FIG. 1 and FIG. 2 differ in that: in the present embodiment the excitation light generated by the excitation light source 801 is converged by the fly eye lenses 803 and 804 and converging lens 805 , then incident on the wavelength conversion device 806 through the light entrance port on the reflecting device 802 . The converted light reflected by the wavelength conversion device 806 is then reflected by the reflecting device 802 and incident on the color filter device 807 . The reflecting device 802 is semi-ellipsoidal or hemispherical and its reflecting surface faces inside. The converted light filtered by the color filter device 807 is further incident to the tapered light guide rod 809 . When the reflecting device 802 is semi-ellipsoidal, the converted light from the vicinity of one focus point of the reflecting device 802 can be reflected to the vicinity of the other focus point; when the reflecting device 802 is hemispherical, if two points are located near the center of the sphere and symmetrical with respect to the center of the sphere, then the reflecting device 802 can approximately reflect the converted light from one symmetrical point to the other. In addition, in other embodiments, the reflecting device 802 can be provided without a light entrance port, and the excitation light source 801 and the reflecting device 802 are provided on the opposite sides of the wavelength conversion device 806 . The excitation light generated by the excitation light source 801 is incident on the wavelength conversion device 806 and the converted light is then transmitted through the wavelength conversion device to the reflecting device 802 .
[0077] It's worth noting that, under the reflection of the reflecting device 802 , the light spot formed by the excitation light generated by the excitation light source 801 incident on the wavelength conversion device 806 and the light spot formed by the converted light incident on the color filter device 807 are located at 0 degree from each other with respect to the center of the ring structure of the wavelength conversion device 806 and the color filter device 807 ; thus, the wavelength conversion area and color filter area of the same color on the wavelength conversion device 806 and color filter device 807 also need to be set at 0 degree from each other with respect to the center of the ring structure of the wavelength conversion device 806 and the color filter device 807 .
[0078] Of course, in other embodiments, through appropriate optical arrangement, the light spot formed by the excitation light incident to the wavelength conversion device 806 and the light spot formed by the converted light incident to the color filter device 807 can be set at any angle from each other with respect to the center of the ring structure of the wavelength conversion device 806 and the color filter device 807 , so the wavelength conversion area and the color filter area of the same color on the wavelength conversion device 806 and color filter device 807 can be set at any angle with respect to the center of the ring structure of the wavelength conversion device 806 and the color filter device 807 .
[0079] Referring to FIG. 12 , FIG. 12 is a schematic structural view of the light source system according to the ninth embodiment of the present invention. The light source system 900 of the present embodiment and the light source system 800 shown in FIG. 11 differ in that: the wavelength conversion device 906 and the color filter device 907 are fixed coaxially by the bracket 908 , and are spaced apart along the axial direction. A tapered light guide rod 909 is provided between the wavelength conversion device 906 and the color filter device 907 . The excitation light generated by the excitation light source 901 is converged by the fly eye lens 903 and 904 and the converging lens 905 , then incident on the wavelength conversion device 906 through the light entrance port on the reflecting device 902 . The converted light reflected by the wavelength conversion device 906 is incident on the reflecting device 902 and reflected. The converted light reflected by the reflecting device 902 is first incident to the light guide rod 909 . The light guide rod 909 collects the converted light in order to reduce the divergence angle of the converted light. After guided by the light guide rod 909 , the converted light is incident on the color filter device 907 , so that the incident angle on the color filter device 907 is smaller, and the filtering effect is improved. In the present embodiment, the light guide rod 909 can also be replaced by other optical device that is able to achieve the functions described above. Further, in the present embodiment, if the wavelength conversion device 906 is a transmission type, the reflecting device 902 can be omitted, and then the converted light is transmitted by the wavelength conversion device 906 and incident on the light guide rod 909 directly.
[0080] As described above, in the embodiment shown in FIG. 11 and FIG. 12 , an illumination light source can be further provided in addition to the excitation light sources 801 and 901 , such as a red illumination light source or a blue illumination light source.
[0081] Referring to FIG. 13 , FIG. 13 is a schematic structural view of the light source system according to the tenth embodiment of the present invention. The light source system 1000 of the present embodiment and the light source system 100 shown in FIG. 1 and FIG. 2 differ in that: the wavelength conversion device 1006 of the present embodiment is a cylindrical structure, and the wavelength conversion areas are provided on the outside surface of the sidewall of the cylindrical structure. The color filter device 1007 has a ring structure. The wavelength conversion device 1006 and the color filter device 1007 are further coaxially fixed on the rotating shaft of the driving device 1008 , and rotate coaxially and synchronously under the driving of the driving device 1008 .
[0082] In the working process of the light source system 1000 according to the present embodiment, the excitation light generated by the excitation light source 1001 is transmitted by the dichroic mirror 1002 , converged by the lens 1003 , then incident on the outside surface of the sidewall of the wavelength conversion device 1006 . The wavelength conversion areas on the outside surface of the sidewall of the wavelength conversion device 1006 convert the excitation light into the converted light and reflect it. After reflected by the wavelength conversion device 1006 , the converted light is guided by the first optical assembly which is comprised of lens 1003 and 1004 and the dichroic mirror 1002 , and incident on the color filter device 1007 . The color filter areas on the color filter device 1007 are provided outside of the cylindrical structure of the wavelength conversion device 1006 , so that the converted light can be incident on them and filtered to improve the color purity. After filtered by the color filter areas of the color filter device 1007 , the converted light is further incident on the light homogenization device 1009 to be made uniform. In other embodiments, the wavelength conversion device 1006 can also transmit the converted light to the color filter device 1007 .
[0083] Referring to FIG. 14 , FIG. 14 is a schematic structural view of the light source system according to the eleventh embodiment of the present invention. The light source system 1100 of the present embodiment and the light source system 100 shown in FIG. 1 and FIG. 2 differ in that: in the present embodiment the wavelength conversion device 1106 and the color filter device 1107 are two cylindrical structures which are fixed coaxially and nested within each other, and the wavelength conversion areas and the first color filter areas are provided on the sidewalls of the two cylindrical structures respectively. The color filter device 1107 is located outside of the wavelength conversion device 1106 . The wavelength conversion device 1106 and the color filter device 1107 are further coaxially fixed on the rotating shaft of the driving device 1108 , and rotate coaxially and synchronously under the driving of the driving device 1108 .
[0084] In the working process of the light source system 1100 according to the present embodiment, the excitation light generated by the excitation light source 1101 is reflected by the reflecting mirror 1102 , converged by the lens 1103 , then incident on the wavelength conversion device 1106 . The wavelength conversion areas of the wavelength conversion device 1106 convert the excitation light into the converted light and transmit it. After being transmitted by the wavelength conversion device 1106 , the converted light is guided by the first optical assembly comprised of lens 1104 and incident on the color filter device 1107 . The color filter areas of the color filter device 1107 filter the converted light to improve its color purity. After filtering by the color filter areas of the color filter device 1107 , the converted light is further incident on the light homogenization device 1109 to be made uniform.
[0085] Referring to in FIG. 15 and FIG. 16 , FIG. 15 is a schematic structural view of the light source system according to the twelfth embodiment of the present invention, and FIG. 16 is the front view of the wavelength conversion device and the color filter device of the light source system shown in FIG. 15 . The light source system 1200 of the present embodiment and the light source system 200 shown in FIG. 3 and FIG. 4 differ in that: in the present embodiment, the wavelength conversion device 1206 and the color filter device 1207 are two strip structures adjoined side by side, where the wavelength conversion areas and the first color filter areas are arranged side by side in the two strip structures. In the present embodiment, the wavelength conversion device 1206 includes a red wavelength conversion area, a green wavelength conversion area, a blue light transmission area and a yellow wavelength conversion area which are arranged side by side sequentially from top to bottom. The color filter device 1207 includes a red color filter area, a green color filter area, a blank area and a yellow color filter area which are arranged side by side sequentially from top to bottom.
[0086] The wavelength conversion device 1206 and the color filter device 1207 move in an oscillating linear translational motion under the driving of a suitable driving device (e.g. a linear motor), so that the red wavelength conversion area, the green wavelength conversion area, the blue light transmission area and the yellow wavelength conversion area of the wavelength conversion device 1206 are periodically provided in the propagation path of the blue excitation light generated by the excitation light source 1201 . The wavelength conversion areas convert the blue excitation light incident on them into converted light of corresponding colors and reflect them, and the blue light transmission area transmits the blue excitation light incident on it. The blue light transmission area can be provided with an appropriate scattering material to destroy the collimation of the blue excitation light. The converted light reflected by the wavelength conversion device 1206 is guided by the first optical assembly comprised of lenses 1203 and 1205 , dichroic mirror 1202 and reflecting mirror 1204 , then incident on the color filter area of corresponding color on the color filter device 1207 , so that it is filtered by the color filter area to improve its color purity. The blue excitation light transmitted by the wavelength conversion device 1206 is guided by the second optical assembly comprised of lens 1210 and 1213 , reflecting mirror 1211 and dichroic mirror 1212 , and combined with the converted light filtered by the color filter device 1207 into one beam of light, which is incident to the light homogenization device 1209 to be made uniform. In the present embodiment, the structure of the wavelength conversion device 1206 and the color filter device 1207 can also be applied to the other embodiments described above, which is not described.
[0087] The present invention further provides a light source assembly constituted by the wavelength conversion device and the color filter device which are described in the above embodiments.
[0088] In summary, in the light source system and the light source assembly of the present invention, the color filter device and the wavelength conversion device are fixed with respect to each other, and they are driven by a same driving device, which can bring the advantages that: the structure is simple, it is easy to implement, and the synchronization effect is excellent.
[0089] The invention is not limited to the above described embodiments. Various modification and variations can be made in the light source device and system of the present invention based on the above descriptions. Thus, it is intended that the present invention cover modifications and variations that come within the scope of the appended claims and their equivalents, as well as the direct or indirect application of the embodiment in other related technical fields. | Provided is a projection system, a light source system, and a light source assembly. The light source system ( 100 ) comprises an excitation light source ( 101 ), a wavelength conversion device ( 106 ), a color filtering device ( 107 ), a drive device ( 108 ), and a first optical assembly. The wavelength conversion device ( 106 ) comprises at least one wavelength conversion region. The optical filtering device ( 107 ) is fixed face-to-face with the wavelength conversion device ( 106 ), and comprises at least a first optical filtering region. The drive device ( 108 ) drives the wavelength conversion device ( 106 ) and the optical filtering device ( 107 ), allowing the wavelength conversion region and the first optical filtering region to act synchronously, and the wavelength conversion region is periodically set on the propagation path of the excitation light, thereby converting the excitation light wavelength into converted light. The first optical assembly allows the converted light to be incident on the first optical filtering region. The first optical filtering region filters the converted light, so as to enhance the color purity of the converted light. The light source system is simple in structure, easy to implement, and highly synchronous. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a mobile telephone battery power supply unit which includes a power detection circuit controlled to detect the current power level of the rechargeable battery of the mobile telephone, and a discharge circuit controlled to discharge the residual voltage out of the rechargeable battery of the mobile telephone before each recharging operation so as to eliminate possible "memory effect". The mobile telephone battery power supply unit comprises a battery case fastened inside the housing thereof and covered by a slide cover, which battery case has batteries that keep providing a constant voltage to the mobile telephone for normal operation as the rechargeable battery of the mobile telephone fails.
A variety of mobile telephones are known and widely in use for the advantage of mobility. However, a mobile telephone must be frequently recharged so that the rechargeable battery of the mobile telephone can be constantly maintained at high level for normal operation. Because of the lack of a power detection means for automatically detecting the current power level of the rechargeable battery of the conventional mobile telephone, the user may forget to recharge the rechargeable battery before it turns to low level. Furthermore, the rechargeable battery of a conventional mobile telephone is generally a nickel-cadmium cell which tends to produce a "memory effect", more particularly after a long use, causing the rechargeable battery not to be fully recharged to the saturation state.
SUMMARY OF THE INVENTION
The present invention eliminates the aforesaid problems. It is therefore an object of the present invention to provide a mobile telephone battery power supply unit which can detect the current power level of the rechargeable battery of a mobile telephone. It is another object of the present invention to provide a mobile telephone battery power supply unit which can discharge the residual voltage out of the rechargeable battery of the mobile telephone before recharging it. It is another object of the present invention to provide a mobile telephone battery power supply unit which prolongs the service life of a mobile telephone. According to one aspect of the present invention, the mobile telephone battery power supply unit is consisted of a housing covered with a slide cover to hold an electronic circuit assembly and battery case on the inside, wherein the electronic circuit assembly includes a power detection circuit controlled to detect the current power level of the rechargeable battery of the mobile telephone to which it is connected, and a discharge circuit controlled to discharge the residual voltage out of the rechargeable battery of the mobile telephone before each recharging operation so as to eliminate possible "memory effect". According to another aspect of the present invention, the battery case receives alkaline batteries, which keep providing a constant voltage to the mobile telephone for normal operation as the rechargeable battery of the mobile telephone fails.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a mobile telephone battery power supply unit embodying the present invention;
FIG. 2 is a plan assembly view thereof;
FIG. 3 illustrates that the mobile telephone battery power supply unit is to be fastened to a mobile telephone for charging its rechargeable battery; and
FIG. 4 is a circuit diagram of the mobile telephone battery power supply unit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2, a mobile telephone battery power supply unit as constructed in accordance with the present invention is generally comprised of a housing 1, an electronic circuit assembly 2, a battery case 3, and a cover 4. The housing 1 of the mobile telephone battery power supply unit comprises a plurality of recessed, paralleled, anti-skid stripes 60 over the front panel 13 thereof. There are also provided on the front panel 13 of the housing 1, a power-indication scale 131, a power detection control button 132, a discharge control button 133, and a plurality of contacts 12 respectively arranged at suitable locations. A socket 121 is made on the bottom end of the housing 1 and electrically connected to the contacts 12. By means of the socket 121, the mobile telephone power supply unit can be connected to an external power supply outlet. There is provided a semi-circular opening 16 on the top end of the housing 1, and a mount 11 on the inside adjacent to the bottom end thereof. The mount 11 comprises a retaining hole 112 on the top, two opposite grooves 111 on two opposite sides, and contacts 12 corresponding to the contacts 12 on the front panel 13 of the housing 1. The holding space of the housing 1 is divided by a division wall 14 into a storage chamber 15, which receives the electronic circuit board 21 and the battery case 3, and a retaining chamber 17, which receives the semi-circular plug portion 41 of the cover 4. The storage chamber 15 has a plurality of posts 151 spaced on the inside for mounting the electronic circuit assembly 2. The housing 1 further comprises two substantially L-shaped peripheral bottom edges 18 on two opposite sides. There are a plurality of inwards projecting strips 191 and retaining slots 19 at the peripheral edges 18 of both sides of the housing 1. The electronic circuit assembly 2 comprises a circuit board 21 having holes 211 at locations corresponding to the posts 151 on the housing 1. By inserting the posts 151 into the holes 211 respectively, the electronic circuit board 21 is firmly retained inside the rechargeable chamber 15. The circuit board 21 of the electronic circuit assembly 2 comprises a set of indicator lamps 22, a power detection micro-switch 23 and a discharge control micro-switch 24 at locations corresponding to the power-indication scale 131, the power detection control button 132 and the discharge control button 133 on the housing 1. The battery case 3 which fits into the rechargeable chamber 15 on the housing 1 comprises two parallel channels 31 in longitudinal direction on two opposite sides for receiving batteries, of which has two conductive elements 32 on two opposite ends. A thermoelement 33 is connected in series between two adjacent conductive elements 32. The thermoelement 33 automatically cuts off the circuit as the temperature surpassed a predetermined range (for example, 80° C.) during charging of the batteries. This arrangement protects the batteries from being excessively charged. The cover 4 has a circular plug portion 41 on one end inserted into the retaining chamber 17 between the semi-circular opening 16 and the division wall 14 on the housing 1, a unitary hook 43 on an opposite end hooked in the retaining hole 112 on the mount 11 of the housing 1, two symmetrical stepped flanges 42, 45 on two opposite sides, two retaining grooves 46 on two opposite sides between the respective stepped flanges 42, 45. Each stepped flange 42, 45 includes an upper flange 42 having a plurality of spaced notches 47, and the both sides of lower flange 45 having projecting strips 44 with retaining slots 441 at locations corresponding to the projecting strips 191 and the retaining slots 19 on the peripheral bottom edges 18 of both sides of the housing 1.
Referring to FIGS. 2 and 3 again, the circuit board 21 of the electronic circuit assembly 2 is fastened inside the storage chamber 15 of the housing 1 with the set of indicator lamps 22, the power detection micro-switch 23 and the discharge control micro-switch 24 respectively electrically connected to the power-indication scale 131, the power detection control button 132 and the discharge control button 133. Then, the battery case 3 is inserted into the storage chamber 15 with the other two separated conductive elements 32 of the parallel channels 31 (on the end opposite to the thermoelement 33) connected to the contacts 12 on the mount 11 of the housing 1. Finally, fasten the cover 4 to the housing 1 over the battery chamber 3 permitting the projecting strips 44 of the lower flanges 45 to hook up with the projecting strips 191 by inserting the projecting strips 44 into the retaining slots 19 and then move the projecting strips 44 to under the projecting strips 191 for combination, the hook 43 to hook in the retaining hole 112 on the mount 11 of the housing 1, and the semi-circular plug portion 41 to insert into the retaining chamber 17 on the housing 1. By means of the upper flanges 42, the mobile telephone power supply unit is fastened to a mobile telephone 5. When assembled, the antenna holder of the mobile telephone 5 is received in the semi-circular opening 48 on the, and the contacts 12 on the mount 11 of the housing 1 are respectively connected to the respective spring contacts on the mobile telephone to form into a closed circuit for providing the mobile telephone 5 with power supply.
Referring to the circuit diagram of present invention as shown in FIG. 4, the third and ninth pins of the driving circuit 50 are connected to an external voltage (reference voltage) which is connected to the positive terminals of the light emitting diodes (set of indicator lamps) 52. The negative terminals of the light emitting diodes 52 are respectively connected to the input terminal of the driving circuit 50. The sixth, seventh and fourth pins of the driving circuit 50 are connected in parallel and then connected to a resistor 53, the base of a n-p-n transistor 54 and the power detection micro-switch 23. The fifth pin of the driving circuit 50 is connected to the variable terminal of a variable resistor 58, which is connected to an external voltage to provide a constant voltage. The variable resistor 58 has an opposite end connected in parallel to the eighth and second pins of the driving circuit 50 and also connected to the resistor 53, the base of the n-p-n transistor 54 and the power detection micro-switch 23. The resistor 53 and the collector of the n-p-n transistor 54 are connected to the external voltage. The emitter of the n-p-n transistor 54 is connected to the positive terminal of a thyristor 55. The thyristor 55 has its gate pulse terminal connected to the external voltage via the discharge control micro-switch 24, and its negative terminal connected to an oscillator circuit 57 via a discharge circuit 56. The oscillator circuit 57 has its earth terminal connected to the negative terminal of one of the light emitting diodes 52 via a transistor (not indicated).
The driving circuit 50 does not work under normal conditions. However, switching on the power detection micro-switch 23 causes the driving circuit 50 to be electrically connected. Once the driving circuit 50 is electrically connected, the external voltage provided through the third and ninth pins of the driving circuit 50 is compared with the reference voltage at the fifth pin. The driving circuit 50 turns on most of light emitting diodes 52 as the external voltage surpassed the reference voltage (the number of the light emitting diodes 52 to be turned on is determined according to the extent of the external voltage surpassed the reference voltage). On the contrary, less number of the light emitting diodes 52 will be turned on. Therefore, the capacity of the electric energy of the batteries (the external voltage) is detected according to the number of the light emitting diodes 52 being turned on.
The rechargeable battery of a mobile telephone is generally of a nickel-cadmium cell which tends to produce a "memory effect", more particularly after a long use, causing a small amount of electric energy constantly maintained on the inside. Because of the "memory effect", a nickel-cadmium cell can not be recharged to the saturation state. This problem of "memory effect" is eliminated from the present invention by mean of the operation of the discharge circuit 56 and the oscillator circuit 57. Switching on the discharge control micro-switch 24 produces a voltage to the gate pulse terminal of the thyristor 55, causing the thyristor 55 to be electrically connected. Once the thyristor 55 was electrically connected, the residual voltage of the rechargeable battery of the connected mobile telephone is charged to the discharge circuit 56. The oscillator circuit 57 oscillate intermittently to produce a discharge cycle for the discharge circuit 56 permitting it to discharge intermittently. Therefore, the residual voltage of the rechargeable battery of the mobile telephone can be completely discharged. As indicated, the earth terminal of the oscillator circuit 57 is connected to the negative terminal of one of the light emitting diodes 52, therefore the light emitting diodes 52 flash according to the frequency of oscillation of the oscillator circuit 57. Once the residual voltage of the rechargeable battery of the mobile telephone has been completely discharged, the light emitting diodes 52 are stopped from flashing, and the rechargeable battery of the mobile telephone can be recharged again. The aforesaid arrangement completely eliminates the problem of "memory effect", and therefore the present invention greatly increases the capacity of a rechargeable battery and simultaneously prolongs its service life. | A mobile telephone battery power supply unit consisted of a housing covered with a slide cover to hold an electronic circuit assembly and battery case on the inside. The electronic circuit assembly includes a charging circuit controlled to recharge the rechargeable battery of a mobile telephone, a power detection circuit controlled to detect the current power level of the rechargeable battery of the mobile telephone, and a discharge circuit controlled to discharge the residual voltage out of the rechargeable battery of the mobile telephone before each recharging operation so as to eliminate possible "memory effect", which prohibits the rechargeable battery from being fully charged to the saturation state. The battery case receives alkaline batteries, which keep providing a constant voltage to the mobile telephone for normal operation as the rechargeable battery of the mobile telephone fails. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part of application Ser. No. 495,901, filed Aug. 8, 1974, which is a division of application Ser. No. 322,226, filed Jan. 9, 1973, now issued as U.S. Pat. No. 3,850,191. It is requested that all patent references cited in these cases be made of record in the present application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to means of limiting reverse fluid flow through conduits. More specifically, the present invention relates to a check valve assembly suitable for employment in a drill string in which drilling fluid or "mud" is being pumped downwardly through the string. The assembly is designed to limit upward flow of fluids when the drill bit enters a high pressure area.
2. Description of the Prior Art
When drilling a well, there may arise a need for a device to prevent the uncontrolled upward flow of the drilling fluid or "mud" in the drill string, e.g., should the drill bit enters a high pressure area. Under normal operating conditions, the device should allow unrestricted downward flow of the mud.
The prior art has suggested a number of valve assemblies designed to allow fluids or effluent materials to be pumped down through a drill string and to prevent reverse or upward flow therethrough. See, for example, U.S. Pat. Nos. 1,577,740 and 1,790,480.
If the valve elements are directly in the flow stream, the materials pumped down through the drill string may erosively wear the valve components, particularly when such materials carry abrasive particles. Previous check valve devices have employed a ball valve member and a seat member, along with a retainer or cage assembly. In these devices, the valve assembly is located directly in the flow stream and therefore subjected to the erosive action of abrasive material in the fluid. Such valves also restrict the downward flow of fluid and, with the valve assembly located directly in the flow stream, it is impossible for equipment to be lowered through the drill string past the assembly.
During drilling operations, the drill string may frequently be removed from the bore for maintenance of the drill bit. The valve assembly should allow fluid to empty from the drill string when it is raised from the bore. It is preferable that the valve assembly also allow fluid to flow at a limited rate upward past the assembly when the drill string is being lowered into the well bore. By allowing the drill string to fill from the bottom, fluid does not have to be pumped in at the top to lower the drill string and to prevent the drill string from collapsing because of pressure differentials. Valve assemblies previously used, either allow no reverse fluid flow, or a predetermined amount of flow at all times. The valve that allows fluid to flow all the time is undesirable. Such a valve works fine when lowering the drill string into the well bore; but, when the drill bit enters a high pressure area, the flow can never be completely stopped.
Other devices have been designed to control only the upward flow of fluid in well tubing and are not designed for use in a drill string, where fluid is allowed in both directions. These devices are used in production strings to shut off the flow of oil if damage occurs to equipment at the wellhead. Many of these devices have a ball valve located in a side pocket out of the flow stream and a movable inner sleeve for displacing the ball from the side pocket when the differential pressure is increased sufficiently.
In the aforementioned U.S. Pat. No. 3,850,191, a new and improved drill string check valve assembly is disclosed which provides an unrestricted flow path for unrestricted downward flow and passage of flowline equipment; but, which is provided with means for regulating the rate of reverse flow so that the drill string can be lowered into the well bore without having to pump fluid into the top of the drill string. In such a check valve, a tubular housing is provided, having a recess in its wall, for normally retaining a ball valve closure member out of the flow stream. Thus, the ball itself doesn't restrict the downward flow of fluid and is at least partially protected from erosion by abrasive material in the fluid. In its preferred form, the closed end of the ball recess may also communicate with the flowbore through a pressure equalizing passage by which the rate of reverse flow can be regulated. Although such a check valve assembly is superior to those of the prior art, the recess, and to some degree, the ball member itself, is still subject to some degree of erosion.
SUMMARY OF THE INVENTION
The present invention provides an improved version of the check valve assembly of U.S. Pat. No. 3,850,191. Its construction further reduces the effects of erosion, resulting in a more efficient and reliable check valve.
Like in the original embodiment, the check valve of the present invention comprises: a valve body having a longitudinal flowbore therethrough; seat means carried by the valve body at one end of the flowbore; and a ball closure means for disposal in a recess for movement into the flowbore for sealing engagement with the seat means, in response to a predetermined rate of reverse flow through the check valve assembly. However, instead of only one recess for disposal of the ball member, the present invention provides a pair of recesses in either one of which the ball member may be disposed. In a preferred embodiment of the invention, the recesses are symmetrically and directly opposed from each other relative to the flowbore. Thus, after entering the flowbore for seating against the seat member, the ball member, upon a reduction in reverse flow, may reenter either one of the recesses, without preference to either. This arrangement materially reduces erosion to the recesses upon continued operation, resulting in a check valve which has a longer life and greater reliability.
The closed end of each of the recesses may also communicate with the flowbore, via a pressure equalizing passage, so that changing of orifice bushings therein can regulate or determine the reverse flow rate at which the check valve will operate.
The foregoing and other features and advantages of the present invention will be more fully understood from the following specification, claims and related drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical elevation, in section, of a check valve assembly according to a preferred embodiment of the invention and illustrating the check valve in the opened or inoperative position;
FIG. 2 is a vertical elevation, in section, similar to FIG. 1 but showing the valve in its closed position for preventing reverse flow therethrough.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, the check valve V of the present invention comprises a cylindrical body 1, having a longitudinal flowbore therethrough, divided into three distinct sections: a converging lower frusto-conical section 2, a restricted central throat section 3 and an upper cylindrical section 4. A threaded pin 5 at the lower end of the assembly and a threaded box 6 at the upper end of the assembly permit connection of the valve assembly V in a drill string above the drill bit (not shown).
Located at the upper end of flowbore section 4 is a valve seat bushing 7 having an annular seating surface 8 thereon. A resilient O-ring seal 9 encircles the bushing 7 and forms a fluidtight seal between the bushing 7 and body 1. To allow for replacement of the bushing 7 and to maintain the correct positioning thereof, an externally threaded lock nut 10 is positioned above the bushing. The lock nut 10 may be provided with slots 11 for engagement with any suitable tool to remove the lock nut for replacement of the bushing 7.
A pair of inclined cylindrical recesses or pockets 12 and 13 communicate with the flowbore near the junction of upper section 4 and central section 3. These pockets may be initially formed by inclined drilling from the outside of the valve body and replacing a portion of the drilled out area with plugs 14 and 15. The drilling, not only produces the recesses 12 and 13, but also provides transition guide areas 16 and 17 from the recesses to the flowbore.
Pressure equalizing passages 18 and 19 may be provided between the closed ends of the recesses 12 and 13 and the lower flowbore section 2. These passages may include a reduced diameter section threaded for receiving externally threaded orifice bushings 21 and 22. The positioning of the passages 18 and 19 may be such as to allow removal of the orifice bushing 21 and 22 from the lower flowbore section 2. It is the size of the orifice 21 and 22 which determines the reverse flow rate permitted.
During drilling operations, fluid is pumped down through the drill string, in which the valve assembly V is installed, through the flowbore sections 4, 3, and 2 and out the drill bit connected therebelow (not shown). The fluid assists the mechanical action of the drill bit and returns cutting to the surface of the well. In addition, when the drill string has to be removed from the well bore, the hydrostatic pressure of the fluid will seal the well bore.
When drilling resumes, after removal of the drill bit, the drill string must again be lowered into the well bore. The drill string is lowered by gravity, until the weight of the fluid displaced by the drill string equals the weight of the drill string. It is then normally necessary to either pump fluid into the top of the drill string to increase its weight or to have a valve assembly, such as the one described herein, to allow the drill string to fill from the bottom. Therefore, it is desirable to have a check valve assembly with reverse flow capabilities like the valve V of the present invention. But, the reverse flow rate must be regulated so that when the drill enters a high pressure area, the valve will completely close and prevent reverse flow or blowout of fluid.
If the pressure below the drill bit is greater than the pressure in the drill string, the fluid will start to flow upwardly through the drill string and when reverse flow reaches a predetermined rate, a ball member 23, which is disposed in either one of the pockets 12 and 13, will be displaced into the flowbore and forced into the contact with the valve seat 8 as in FIG. 2. The diameter of the ball 23 is slightly less than the diameter of the recesses 12 and 13 and the upper flowbore section 4.
The ball 23 is displaced because of a pressure differential created between the recesses and the restricted bore of throat section 3. This pressure differential exists because the entire hydraulic head within the recess is in the form of pressure energy, whereas the same hydraulic head in the throat 3 is in the form of kinetic energy embodied in the fluid flow. The pressure at the throat or intermediate section 3 is therefore lower than that in the recesses 12 and 13. This is in accordance with the well established principle outlined in hydraulic textbooks, e.g., "Fluid Dynamics" by Daily and Harleman (Addison-Wesley, 1966), and which is expressed quantitatively by the well known equation of Bernoulli.
When the orifice bushings 21 and 22 are blanked off so as to allow no communication of pressure, the initial pressure differential acting on the ball 23 will be at a maximum. However, if an orifice is fitted into the bushing, some reduction of pressure will take place in the recesses due to this communication. The larger the orifice the higher the flow rate required to cause the ball 23 to be displaced from its recess into the flowbore for engagement with the valve seat 8, as illustrated in FIG. 2.
Subsequently, when the pressure below the valve assembly V becomes less than the pressure above, the ball 23 will drop down through the upper flowbore section 4 and be guided by one of the guide areas 16 or 17 into one of the recesses or pockets 12 or 13 respectively. Since the recesses are symmetrically disposed about the axis of the flowbore, the ball does not prefer one to the other and depending on the fluids, the plumbness of the drill string and other variables may enter either one. Thx passages 18 or 19, or the clearance between the ball 23 and the recess in which it reenters, will allow the fluid displaced by the ball to escape from the recess. When the ball has returned to either one of the recesses 12 or 13, the drilling process can be resumed.
From the foregoing description, it can be seen that the check valve of the present invention offers several advantages. It permits some reverse flow of fluids, so a drill string can be lowered into the well bore without extra weight to overcome the buoyancy of the drilling mud therearound, yet it prevents excessive reverse flow which might occur upon drilling entry into an extreme high pressure area. The closure member is disposed in recesses out of the main flow stream, reducing erosion wear and by providing a pair of recesses for the closure member, erosion wear is further reduced. The resulting check valve assembly V is simple, effective and efficient.
Although only one embodiment of the invention has been described herein, many changes in the size, shape, materials, as well as the details of construction, may be made without departing from the spirit of the invention. It is therefore intended that the scope of the invention be limited only by the claims which follow. | A check valve assembly for use in a drill string to limit reverse flow of drilling fluid through the string while permitting such fluid to be pumped freely into the well under normal conditions. The assembly may include: a valve body having a longitudinal flowbore therethrough; a valve seat at one end of the flowbore; a pair of inclined cylindrical recesses in the valve body communicating with the flowbore; and a ball member normally disposed in either one of the recesses and movable into the flowbore for sealing engagement with the seat in response to a predetermined rate of reverse flow through the flowbore. | 8 |
RELATED APPLICATIONS
The present application claims priority to Japanese Application Number 2014-216252, filed Oct. 23, 2014, the disclosure of which is hereby incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an injection molding system configured to perform a set of work of inspecting, classifying, and packing the molded item fallen freely from a molding device continuously and in short time.
2. Description of the Related Art
The present invention relates to an injection molding system configured to perform a set of work of inspecting, classifying, and packing the molded item fallen freely from a molding device continuously and in short time.
In molding by an injection molding machine, there is a case in which a molded item is made to fall to a box for reducing cycle time. The molded item in the box is sent to inspection process and inspected whether the item is defective or not by an image processing inspection device. At the inspection, the molded items loaded in bulk need to be set on the image processing inspection device one by one, requiring man hours.
When the molded item is inspected by the image processing inspection device, it is necessary to inspect portions liable to crack or have burring, but there is a case in which the portions can be inspected only at specified angle based on the place of the portions.
A technique disclosed in Japanese Patent Laid-Open No. 2013-24852 performs inspection more simply an less expensively by showing a face of a workpiece to be inspected by an articulated robot. The articulated robot releases the workpiece in non defective item chute when the item is non defective, and releases the item in defective item chute when the item is defective.
In a technique disclosed in Japanese Patent Laid-Open No. 9-123232, a plurality of molded items simultaneously molded by a mold are grasped and taken out by a plurality of grasping units of a take-out hand, arranged at targeted molded item pitch during conveyance, and sent to the next process.
Though effective inspection process is proposed in Japanese Patent Laid-Open No. 9-123232, a processing line includes not only the inspection process but also molding process, packing process, and the like before or after the inspection process. Therefore, it is necessary to reduce the total time throughout the all processes.
In a technique disclosed in Japanese Patent Laid-Open No. 9-123232, since the molded items are taken out by take-out units, time for the take-out unit to move in the mold is required. In addition to that, a large sized hand equipped with a movement mechanism of the molded item is required and time is taken for the taking out of the molded item.
SUMMARY OF THE INVENTION
An injection molding system according to the present invention is one for making a molded item freely fall in demolding process from a mold, the injection molding system including a molded item photographing device for capturing image of the molded item fallen freely, an image analysis device configured to perform image analysis of the image photographed by the molded item photographing device, and a molded item classification device configured to classify the molded item to one of a plurality of predetermined regions based on result of the image analysis, wherein the image analysis device is configured to perform analysis of appearance feature of the molded item, and make the item classification unit classify the molded item based on result of the analysis.
The molded item photographing device may be fixed to the molded item classification unit.
The molded item photographing device may be fixed and configured to photograph free fall region of the molded item falling freely.
The injection molding system according may include, a first molded item photographing device for capturing image of the molded item fallen freely and determining position of the molded item, a second molded item photographing device for photographing the molded item to analyze image of the molded item, and a molded item movement device configured to grasp the molded item at the position of the molded item determined by the first molded item photographing device and move the molded item to photographing position for photographing the molded item by the second molded item photographing device, wherein the image analysis unit is configured to analyze the image photographed by the second molded item photographing device.
The first molded item photographing unit may be fixed to the molded item movement device.
The second molded item photographing unit may photograph free fall region of the molded item.
The appearance feature of the molded item may include at least one of, whether presence of defective part in molding, cavity number transcribed to the molded item, configuration of the molded item, and color of the molded item.
At least one of the plurality of predetermined regions may be a region on a molded item conveyer.
At least one of the plurality of predetermined regions may be a region in a storing box or in a storing vessel for containing the molded item.
The molded item classification device may align the molded item at the predetermined region.
The molded item classification device and the molded item movement device may be the same device.
The injection molding system according may further includes a communication unit configured to output the result of analysis of the image analysis device, wherein result of analysis or result of classification is configured to be input to production management process data of the injection molding system.
The present invention, with the above configuration, can provide an injection molding system with reduced cycle time by performing a set of work of inspecting, classifying, and packing of the molded item fallen freely from the molding device continuously and in short time.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-described object, the other object, and the feature of the invention will be proved from the description of embodiments below with reference to the accompanying drawings. In these drawings:
FIG. 1 is a top view of an injection molding system.
FIG. 2 is a front view of an injection molding system.
FIGS. 3A and 3B are diagrams illustrating classification and alignment of a molded item.
FIG. 4 is a view illustrating a parallel link robot to which an image processing inspection camera is fixed
FIG. 5 is a diagram illustrating production management process data of an injection molding machine of classification and alignment of a molded item shown in FIG. 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1, 2 are a schematic diagram of an injection molding system according to the present invention. The injection molding system consists of an injection molding machine 1 , a mold 2 , a conveyer 3 , a position determination camera 4 , a parallel link robot 5 , an image processing inspection camera 6 , a non defective item packing box 7 , a defective item packing box 8 , and a stand 9 .
The parallel link robot 5 works as a molded item movement device, a molded item classification device, and an image analysis device. The image processing inspection camera 6 corresponds to the molded item photographing device in claim 1 , and the second molded item photographing device in claim 4 . The position determination camera 4 corresponds to the first molded item photographing device in claim 4 .
A molded item 10 molded in the mold 2 of the injection molding machine 1 is demolded by ejection by an ejector not shown in the figure, to fall on the conveyer 3 installed below the mold 2 , after the stationary mold 2 a and a movable mold 2 b are opened. At the falling, position and direction of the molded item are random. After the position determination camera 4 detects the molded item 10 conveyed by the conveyer 3 , the parallel link robot 5 grasps the molded item. The parallel link robot 5 shows the grasped molded item 10 to the image processing inspection camera 6 , and packs the molded item 10 in the non defective item packing box 7 when the molded item is a non defective item, and releases the molded item 10 in the defective item packing box 8 when the molded item is a defective item, as shown in FIG. 3 . The parallel link robot 5 turns the molded item 10 such that the molded item 10 can be contained in a partitioned space in the non defective packing box 7 , before the parallel link robot 5 packs the molded item 10 in the non defective packing box 7 .
Cavity number is usually stamped on the molded item, and the molded item is usually managed according to a cavity, since it can be determined to which molded item is defective when the defective items are generated by a specific mold core which is damaged. Therefore, the cavity number of the molded item 10 is determined when the position determination unit 4 photographs the molded item 10 , and the parallel link robot 5 packs the molded item 10 in each region corresponding to each cavity number. In FIG. 3 , rows corresponding to each cavity number are provided in the non defective item packing box 7 , and the molded item in the first cavity is packed in a row of the first cavity. Similarly, the molded item in the second cavity is packed in a row of the second cavity, the molded item in the third cavity is packed in a row of the third cavity, and the molded item in the fourth cavity is packed in a row of the fourth cavity.
As mentioned above, in the present embodiment, a set of work of inspecting, classifying, and packing the molded item fallen freely from the molding device can be performed continuously and in short time.
In the present embodiment, the molded item is classified based on the presence of a defective part in molding and the cavity number transcribed to the molded item 10 , but molded item identification number, configuration of the molded item, color of the molded item may be used for the classification.
In the present embodiment, the molded item is packed in the packing box, but the molded item may be aligned on a palette or a conveyer.
The conveyer 3 may be moved in constant speed or by pitch feeding. When the conveyer 3 is moved in constant speed, movement distance of the molded item during time from when the position determination camera 4 photographs to when the parallel link robot 5 grasps the molded item is corrected using an encoder or calculation based on speed of the conveyer. When the conveyer 3 is moved by pitch feeding, the conveyer 3 is moved for a fixed distance after all molded items 10 in a range photographed by the position determination camera 4 .
A plurality of parallel link robots may be used as a molded item movement device. A plurality of parallel link robots may be used for each of the molded item movement device and the molded item classification device.
The molded item movement device may be a parallel link robot or an articulated robot. The image processing inspection camera 6 may be fixed such that the image processing inspection camera 6 can photograph the free fall region where the molded item freely falls. More specifically, the molded item may be fallen to, for example, a saucer instead of the conveyer 3 , and the robot may grasp the itemed item on the saucer.
The image processing inspection camera 6 may be fixed to the parallel link robot 5 as shown in FIG. 4 . Operation of the parallel link robot 5 to grasp the molded item 10 and show the molded item 10 to the image processing inspection camera 6 can be omitted, thus the cycle time can be reduced.
When the image processing inspection camera 6 determines that the molded item 10 is defective, the image processing inspection camera 6 transmits the information to the injection molding device 1 . As shown in FIG. 5 , the injection molding machine 1 stores data of shot number at which the molded item is defective as production management process data. The operator can easily grasp in what molding condition the defective item generates.
A bucket may be set on the conveyer 3 for precisely determining the shot number of the molded item the image analysis device analyzing the image thereof, and the conveyer may be fed at each shot time for a pitch of the bucket. The molded items for a shot fall from the mold to one bucket, thus the molded items of the first shot, those of the second shot, those of the third shot, and so on are conveyed to the image processing inspection camera 6 . | An injection molding system for making a molded item freely fall in demolding process from a mold, the injection molding system comprising:
a molded item photographing device, an image analysis device, and a molded item classification device, wherein the image analysis device is configured to perform analysis of appearance feature of the molded item, and make the item classification unit classify the molded item based on result of the analysis. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is the U.S. National Phase of International Patent Application Serial No. PCT/US2014/023519, filed Mar. 11, 2014, which claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application Ser. No. 61/775,807, filed Mar. 11, 2013, the disclosures of which are incorporated herein by reference in their entireties.
BACKGROUND
Numerous impressive catalysts have been developed in transition metal catalysis and organocatalysis with unique activation modes. However, the utility of such catalysts is hampered by inherent drawbacks like limited reaction scopes and high catalyst loading. In an effort to improve upon these limitations, the concept of combing transition metal catalysis and organocatalysis has emerged in the last few years. Strategies, including cooperative catalysis, synergistic catalysis, and sequential/relay catalysis, have been established. However, the incompatibility between catalysts, substrates, intermediates and solvents is the potential shortcoming.
SUMMARY
The present document describes a ligand having the structure or its enantiomer:
wherein: each one of R a , R b , R c , and R d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH 2 NH; *CH(CH 3 )NH(C*,R); and *CH(CH 3 )NH(C*,S); and the organocatalyst is an organic molecule catalyst covalently bound to the bridge group. In one embodiment, at least one of R a , R b , R c , and R d is an aryl moiety selected from phenyl; P—CH 3 phenyl; 3,5-di-CH 3 phenyl; 3,5-di-t-butyl phenyl; 3,5-di-CH 3 phenyl; 2-CH 3 phenyl; C 6 F 5 ; 2-naphthyl; and 1-naphthyl. In another embodiment, at least one of R a , R b , R c , and R d is an alkyl moiety selected from t-butyl and i-propyl. In an additional embodiment, at least one of R a , R b , R c , and R d is a cycloalkyl moiety selected from cyclohexyl and cyclopentyl.
Also provided is a catalyst having the structure or its enantiomer:
wherein: each one of R a , R b , R c , and R d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH 2 NH; *CH(CH 3 )NH(C*,R); and *CH(CH 3 )NH(C*,S); the organocatalyst is an organic molecule catalyst covalently bound to the bridge group; and M is selected from Rh, Pd, Cu, Ru, Ir, Ag, Au, Zn, Ni, Co, and Fe. In one embodiment, at least one of R a , R b , R c , and R d is an aryl moiety selected from phenyl; P—CH 3 phenyl; 3,5-di-CH 3 phenyl; 3,5-di-t-butyl phenyl; 3,5-di-CF 3 phenyl; 2-CH 3 phenyl; C 6 F 5 ; 2-naphthyl; and 1-naphthyl. In another embodiment, at least one of R a , R b , R c , and R d is an alkyl moiety selected from t-butyl and i-propyl. In yet another embodiment, at least one of R a , R b , R c , and R d is a cycloalkyl moiety selected from cyclohexyl and cyclopentyl.
Also provided is a method for the asymmetric hydrogenation of an alkene to a corresponding alkane that includes the step of combining an alkene in a suitable solvent with an excess of hydrogen gas and a catalytically effective amount of a catalyst according to the present disclosure at a temperature and pressure effective to hydrogenate the alkene. In one embodiment, the solvent includes isopropanol. In another embodiment, at least one of R a , R b , R c , and R d in the catalyst is an aryl moiety selected from phenyl; P—CH 3 phenyl; 3,5-di-CH 3 phenyl; 3,5-di-t-butyl phenyl; 3,5-di-CF 3 phenyl; 2-CH 3 phenyl; C 6 F 5 ; 2-naphthyl; and 1-naphthyl. In yet another embodiment, at least one of R a , R b , R c , and R d in the catalyst is an alkyl moiety selected from t-butyl and i-propyl. In a further embodiment, at least one of R a , R b , R c , and R d in the catalyst is a cycloalkyl moiety selected from cyclohexyl and cyclopentyl.
DETAILED DESCRIPTION
This document describes ligands and catalysts prepared therefrom that provide unexpected improvements in conversion and selectivity in comparison with individual metal catalysts and organocatalysts by covalently bonding chiral bisphosphines with organocatalysts. Metal complexed with bisphosphine is a general catalyst and can lead many metal-catalyzed reactions with high turnovers. Organocatalysts activate substrates and influence selectivities. As used herein, the term “metallorganocatalysis” refers to catalysts and reactions catalyzed by a compound having a metal catalyst portion covalently bound to an organocatalyst portion. The high activity derived from the metal portion and high selectivity from the organocatalyst provide a useful approach in asymmetric catalysis.
As employed above and throughout the disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings:
The term “alkyl” refers to the radical of saturated aliphatic groups, including straight-chain alkyl groups and branched-chain alkyl groups. The term “cycloalkyl” refers to a non-aromatic mono or multicyclic ring system of about 3 to 7 carbon atoms. Examples of cycloalkyl groups include cyclopropyl cyclobutyl, cyclopentyl, cyclohexyl and the like.
The term “aryl” refers to any functional group or substituent derived from a simple aromatic ring, be it phenyl, thienyl, indolyl, etc.
Disclosed herein is a ligand having the structure or its enantiomer;
wherein:
each one of R a , R b , R c , and R d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH 2 NH; *CH(CH 3 )NH(C*,R); and *CH(CH 3 )NH(C*,S); and the organocatalyst is an organic molecule catalyst covalently bound to the bridge group.
Each one of R a , R b , R c , and R d can be the same as or different from any of the other R groups. For example, in one embodiment, all of R a , R b , R c , and R d are the same aryl group. In another embodiment, each one of R a , R b , R c , and R d is a different aryl group. In yet another embodiment, R a and R b are different aryl groups, while R c is an alkyl group and R d is a cycloalkyl group.
Preferred aryl moieties for R a , R b , R c , and R d include phenyl; P—CH 3 phenyl; 3,5-di-CH 3 phenyl; 3,5-di-t-butyl phenyl; 3,5-di-CF 3 phenyl; 2-CH 3 phenyl; C 6 F 5 ; 2-naphthyl; and 1-naphthyl. Preferred cycloalkyl moieties (e.g. “Cy”) for R a , R b , R c , and R d include cyclohexyl and cyclopentyl. Preferred alkyl moieties for R a , R b , R c , and R d include t-butyl and i-propyl.
The term “organocatalyst” as used herein includes organic molecules capable of catalyzing a reaction. Suitable organocatalysts contain at least one moiety that can be covalently bound to a bridge group in the ligand of structure (I) or the catalyst of structure (II). Preferred organocatalysts include a thiourea moiety that can be covalently bound to a bridge group. Exemplary organocatalysts include, but are not limited to, the following structures designated as OC1-OC25:
Preferred ligands are represented by the following formulas:
Alternatively, the PPh 2 group in any of the ligands listed above can be PR a R b or PR c R d , wherein each one of R a , R b , R c , and R d is selected from alkyl, cycloalkyl, and aryl. Preferred aryl moieties for R include phenyl; P—CH 3 phenyl; 3,5-di-CH 3 phenyl; 3,5-di-t-butyl phenyl; 3,5-di-CF 3 phenyl; 2-CH 3 phenyl; C 6 F 5 ; 2-naphthyl; and 1-naphthyl. Preferred cycloalkyl moieties for R include cyclohexyl and cyclopentyl. Preferred alkyl moieties for R include t-butyl and i-propyl.
Each one of R a , R b , R c , and R d can be the same as or different from any of the other R groups. For example, in one embodiment, all of R a , R b , R c , and R d are the same aryl group. In another embodiment, each one of R a , R b , R c , and R d is a different aryl group. In yet another embodiment, R a and R b are different aryl groups, while R c is an alkyl group and R d is a cycloalkyl group.
Also disclosed herein is a catalyst having the structure or its enantiomer:
wherein:
each one of R a , R b , R c , and R d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH 2 NH; *CH(CH 3 )NH(C*,R); and *CH(CH 3 )NH(C*,S); and the organocatalyst is an organic molecule catalyst covalently bound to the bridge group. In one embodiment, the bridge group is part of the organocatalyst molecule, for example, a thiourea moiety for dual hydrogen bonding.
Each one of R a , R b , R c , and R d can be the same as or different from any of the other R groups. For example, in one embodiment, all of R a , R b , R c , and R d are the same aryl group. In another embodiment, each one of R a , R b , R c , and R d is a different aryl group. In yet another embodiment, R a and R b are different aryl groups, while R c is an alkyl group and R d is a cycloalkyl group.
Preferred aryl moieties for R a , R b , R c , and R d include phenyl; P—CH 3 phenyl; 3,5-di-CH 3 phenyl; 3,5-di-t-butyl phenyl; 3,5-di-CF 3 phenyl; 2-CH 3 phenyl; C 6 F 5 ; 2-naphthyl; and 1-naphthyl. Preferred cycloalkyl moieties for R a , R b , R c , and R d include cyclohexyl and cyclopentyl. Preferred alkyl moieties for R a , R b , R c , and R d include t-butyl and i-propyl.
The term “organocatalyst” as used herein includes organic molecules capable of catalyzing a reaction. Suitable organocatalysts contain at least one moiety that can be covalently bound to a bridge group in the ligand of structure (I) or the catalyst of structure (II). Preferred organocatalysts include a thiourea moiety that can be covalently bound to a bridge group. Exemplary organocatalysts include, but are not limited to those listed above.
When a metal catalyst and an organocatalyst are linked through a covalent bond, cooperative interactions such as the following interaction modes offer high activities and selectivities.
Exemplary methods for preparing the ligands and catalysts described herein are discussed in the Examples section.
The catalysts disclosed herein are useful for a wide range of reactions, including, but not limited to, asymmetric hydrogenation, hydroformylation, aldol, Diels-Alder, hetereo Diels-Alder, Mannich, Michael addition, allylic alkylation, alkylation, Friedel-Crafts, ene, Baylis-Hillman, fluorination, and Henry reactions. In one embodiment depicted in the Examples, a method for the asymmetric hydrogenation of an alkene, imine, ketone, or thioketone to a corresponding alkane, amine, alcohol, or thiol is provided, which includes combining an alkene, imine, ketone, or thioketone in a suitable solvent with an excess of hydrogen gas and a catalytically effective amount of a catalyst disclosed herein, and at a temperature and pressure effective to hydrogenate the alkene, imine, ketone or thioketone. In one embodiment, asymmetric hydrogenation of β,β-disubstituted nitroalkenes provided up to >99% conversion and 99% enantioselectivity.
Suitable solvents include, but are not limited to, polar organic solvents. An exemplary polar organic solvent includes, but is not limited to, isopropanol. A catalytically effective amount of a catalyst can be readily determined by one of skill in the art and includes amounts effective to convert an alkene, imine, or ketone to a corresponding chiral alkane, amine, or alcohol.
The following non-limiting examples serves to further illustrate the present invention.
EXAMPLES
Materials and Methods
All reactions dealing with air- or moisture-sensitive compounds were carried out in a dry reaction vessel under a positive pressure of nitrogen or in a nitrogen-filled glovebox. Unless otherwise noted, all reagents and solvents were purchased from commercial suppliers without further purification. Anhydrous solvents were purchased from Sigma-Aldrich and transferred by syringe. Purification of products was carried out by chromatography using silica gel from ACROS (0.06-0.20 mm) and analytical thin layer chromatography (TLC) was carried out using silica gel plates from Merck (GF254). [Rh(COD)Cl] 2 , [Rh(COD) 2 ]BF 4 and [Rh(COD) 2 ]SbF 6 were purchased from Heraeus. The HPLC solvents were purchase from Alfa (n-Hexane) and Sigma-Aldrich (2-Propanol).
1 H NMR, 13 C NMR and 31 P NMR spectra were recorded on a Bruker Avance (400 MHz) spectrometer with CDCl 3 as the solvent and tetramethylsilane (TMS) as the internal standard. Chemical shifts are reported in parts per million (ppm, δ scale) downfield from TMS at 0.00 ppm and referenced to the CDCl 3 at 7.26 ppm (for 1 H NMR) or 77.0 ppm (for deuterochloroform). Data are reported as: multiplicity (s=singlet, d=doublet, t=triplet, q=quartet, m=multiplet), coupling constant in hertz (Hz) and signal area integration in natural numbers. 13 C NMR and 31 P NMR analyses were run with decoupling.
Enantiomeric excess values (“ee”) were determined by Daicel chiral column on an Agilent 1200 Series HPLC instrument or an Agilent 7980 Series GC instrument. New compounds were further characterized by high resolution mass spectra (HRMS) on a Waters Q-T of Ultima mass spectrometer with an electrospray ionization source (University of Illinois, SCS, Mass Spectrometry Lab). Optical rotations [α] D were measured on a PERKINELMER polarimeter 343 instrument.
All (E)-β,β-disubstituted nitroalkenes were prepared according the literature. (Li, S., et al., Angew. Chem. Int. Ed. 2012, 51, 8573-8576). All N—H imines were prepared according to the literature. (Hou, G., et al., J. Am. Chem. Soc. 2009, 131, 9882-9883.) The absolute configuration of products were determined by comparison of analytical data with the literature (HPLC spectra, optical rotation). The absolute configuration of others were assigned by analogy.
Example 1—Synthesis of Ligands
Ligands L1-L3 were prepared according the according the literature (Hayashi, T., et al., Bull. Chem. Soc. Jpn. 1980, 53, 1138-1151) with a slight modification: column chromatography was performed using silica gel (hexane/ethyl acetate for L1 and dichloromethane/methanol for L2) instead of alumina (hexane/benzene for L1 and ether/ethyl acetate for L2). All the spectral data are consistent with the literature values.
Under an argon atmosphere, 3,5-bis(trifluoromethyl)phenyl isothiocyanate (1.1 mmol) was added to a solution of L2 (1.0 mmol) in dry DCM (1.0 ml). After the reaction mixture was stirred overnight, the reaction mixture was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (hexane/ethyl acetate=9/1 as eluant) gave L8 as yellow solid (640 mg, 74%). L8 was characterized as follows:
1 H NMR (400 MHz, CDCl 3 ) δ 7.69 (s, 3H), 7.33-7.12 (m, 19H), 7.11-7.01 (m, 3H), 5.53 (s, 1H), 4.47 (d, J=7.2 Hz, 2H), 4.28 (s, 1H), 4.18 (t, J=2.3 Hz, 1H), 3.96 (s, 1H), 3.56 (s, 1H), 3.45 (s, 1H), 1.42 (d, J=6.6 Hz, 1H).
13 C NMR (100 MHz, CDCl 3 ) δ 178.37 (s), 139.18 (s), 138.94 (d, J=9.6 Hz), 138.82 (d, J=6.3 Hz), 138.04 (d, J=9.4 Hz), 135.55 (d, J=5.0 Hz), 134.68 (d, J=21.2 Hz), 133.71 (d, J=20.1 Hz), 133.01 (d, J=19.2 Hz), 132.20 (d, J=17.8 Hz), 129.58 (s), 128.97-127.94 (m), 124.48 (s), 124.31 (s), 121.60 (s), 119.16 (s), 95.36 (d, J=24.1 Hz), 77.63 (d, J=8.5 Hz), 75.34 (d, J=20.4 Hz), 74.16 (d, J=9.1 Hz), 73.84 (d, J=4.9 Hz), 73.37 (d, J=8.5 Hz), 73.10-72.50 (m), 71.97 (d, J=2.6 Hz), 50.87 (s), 21.86 (s).
31 P NMR (162 MHz, CDCl 3 ) δ −17.81 (s), −25.08 (s).
[α] D 25 =237.3° (c=0.30, CHCl 3 )
HRMS (ESI): [M+H + ] Calc. 869.1406. found 869.1401.
1 H NMR (400 MHz, CDCl 3 ) δ 7.54 (s, 2H), 7.42-7.38 (m, 3H), 7.34-7.14 (m, 18H), 5.13 (s, 2H), 5.13-5.07 (m, 1H), 4.48 (d, J=1.7 Hz, 2H), 4.37 (d, J=7.4 Hz, 2H), 4.19 (d, J=8.1 Hz, 2H), 4.14 (t, J=2.3 Hz, 1H), 3.65 (s, 1H), 3.57 (s, 1H), 1.46 (d, J=6.7 Hz, 3H).
13 C NMR (100 MHz, CDCl 3 ) δ 152.34 (s), 140.51 (s), 140.39 (s), 138.90 (d, J=9.7 Hz), 138.14 (d, J=9.4 Hz), 135.89 (d, J=8.1 Hz), 134.92 (d, J=21.2 Hz), 133.60 (d, J=20.0 Hz), 133.06 (d, J=19.2 Hz), 132.44 (d, J=18.8 Hz), 131.76 (d, J=33.2 Hz), 129.39 (s), 128.72 (s), 128.62-127.96 (m), 124.55 (s), 121.84 (s), 118.11 (d, J=3.1 Hz), 115.21 (s), 95.11 (d, J=23.6 Hz), 77.19 (s), 75.78 (d, J=10.3 Hz), 75.36 (d, J=19.6 Hz), 74.33 (d, J=3.0 Hz), 73.42-71.18 (m), 73.11 (d, J=4.5 Hz), 71.67 (d, J=2.2 Hz), 71.24 (d, J=1.9 Hz), 45.48 (d, J=7.1 Hz), 20.65 (s).
HRMS (ESI): [M+H + ] Calc. 853.1635. found 853.1644.
[α] D 25 =262.1° (c=0.33, CHCl 3 ).
1 H NMR (400 MHz, CDCl 3 ) δ 7.44 (t, J=7.2 Hz, 2H), 7.40-7.11 (m, 24H), 6.00 (s, 2H), 5.46 (s, 1H), 4.60 (s, 1H), 4.57-3.52 (m, 4H), 3.56 (d, J=10.8 Hz, 2H), 1.35 (d, J=6.6 Hz, 3H), 1.04 (d, J=6.2 Hz, 3H).
13 C NMR (100 MHz, CDCl 3 ) δ 178.66 (s), 141.83 (s), 139.05 (d, J=2.9 Hz), 138.97 (s), 138.23 (d, J=9.6 Hz), 136.13 (d, J=7.2 Hz), 134.71 (d, J=21.0 Hz), 133.62 (d, J=20.1 Hz), 132.98 (d, J=19.2 Hz), 132.55 (d, J=18.6 Hz), 129.29 (s), 128.98-127.45 (m), 125.65 (s), 95.44 (d, J=23.6 Hz), 77.17 (d, J=8.1 Hz), 75.25 (d, J=19.9 Hz), 74.80 (d, J=10.3 Hz), 74.08 (d, J=4.5 Hz), 73.25 (d, J=9.0 Hz), 73.13 (s), 72.72 (d, J=4.3 Hz), 72.41 (s), 71.50 (d, J=2.6 Hz), 52.79 (s), 50.51 (s), 23.82 (s), 21.45 (s).
31 P NMR (162 MHz, CDCl 3 ) δ −17.66 (s), −25.81 (s).
HRMS (ESI): [M+H + ] Calc. 761.1972. found 761.1972.
[α] D 25 =343.5° (c=0.21, CHCl 3 ).
1 H NMR (400 MHz, CDCl 3 ) δ 8.21 (t, J=9.1 Hz, 1H), 7.59 (s, 1H), 7.25-6.92 (m, 23H), 5.51-5.41 (m, 1H), 4.43-4.38 (m, 2H), 4.29 (s, 1H), 4.17 (s, 1H), 3.70 (s, 1H), 3.40 (s, 1H), 3.09 (s, 1H), 2.42 (s, 6H), 1.24 (d, J=6.9 Hz, 3H).
13 C NMR (100 MHz, CDCl 3 ) δ 178.51 (s), 140.22 (s), 139.32 (d, J=9.9 Hz), 138.56 (d, J=5.4 Hz), 138.03 (d, J=9.7 Hz), 135.93 (s), 134.64 (d, J=21.2 Hz), 133.84 (d, J=20.4 Hz), 132.76 (d, J=18.9 Hz), 132.08 (d, J=17.5 Hz), 129.27 (d, J=17.7 Hz), 128.67 (s), 128.29-127.92 (m), 96.88 (d, J=24.1 Hz), 75.39 (d, J=22.6 Hz), 73.95 (d, J=5.3 Hz), 73.65 (d, J=5.6 Hz), 72.98 (d, J=6.8 Hz), 72.81 (s), 72.56 (d, J=3.7 Hz), 72.16 (d, J=3.6 Hz), 51.84 (s), 24.43 (s), 21.48 (s).
31 P NMR (162 MHz, CDCl 3 ) δ −17.61 (s), −25.96 (s).
HRMS (ESI): [M+H + ] Calc. 761.1972. found 761.1964.
[α] D 25 =−219.9° (c=0.22, CHCl 3 )
1 H NMR (400 MHz, CDCl 3 ) δ 8.22 (s, 1H), 7.73 (d, J=8.4 Hz, 2H), 7.71-7.64 (m, 1H), 7.35-7.13 (m, 18H), 7.08-7.02 (m, 4H), 5.56-5.46 (m, 1H), 4.45 (s, 1H), 4.32 (s, 1H), 4.25 (s, 1H), 4.17 (t, J=2.4 Hz, 1H), 3.72 (s, 1H), 3.50 (s, 1H), 3.26 (s, 1H), 1.33 (d, J=6.8 Hz, 1H).
13 C NMR (100 MHz, CDCl 3 ) δ 178.11 (s), 139.79 (s), 139.14 (d, J=9.8 Hz), 138.63 (d, J=5.5 Hz), 137.96 (d, J=9.4 Hz), 135.58 (d, J=4.5 Hz), 134.68 (d, J=21.2 Hz), 133.81 (d, J=20.3 Hz), 132.83 (d, J=18.9 Hz), 132.22 (s), 130.27-129.77 (m), 128.78 (s), 128.66-128.01 (m), 127.27 (d, J=3.4 Hz), 125.01 (s), 95.87 (d, J=24.2 Hz), 77.59 (d, J=8.6 Hz), 75.42 (d, J=22.0 Hz), 73.63 (d, J=5.2 Hz), 73.14 (d, J=7.2 Hz), 72.83 (s), 72.08 (d, J=3.0 Hz), 51.60 (s), 23.10 (s).
31 P NMR (162 MHz, CDCl 3 ) δ −17.85 (s), −26.34 (s).
HRMS (ESI): [M+H + ] Calc. 801.1532. found 801.1538.
[α] D 25 =−239.5° (c=0.30, CHCl 3 )
Ligands L9-L14 were prepared according the according the literature (Zhao, Q., et al., Org. Lett. 2013, 15, 4014-4017).
Ligands L15-L17 were synthesized as follows:
SI2 was prepared according the according the literature (Zhao, Q., et al., Org. Lett. 2013, 15, 4014-4017). SI3 was prepared according the according the literature (Gotov, B., et al., New J. Chem. 2000, 24, 597-602). Under a nitrogen atmosphere, 3,5-bis(trifluoromethyl)phenyl isothiocyanate (1.1 mmol) as added to a solution of SI3 (1.0 mmol) in dry DCM (1.0 ml). After the reaction mixture was stirred overnight, the reaction mixture was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (hexane/ethyl acetate=9/1 as eluant) gave L15 as yellow solid.
L15: 1 H NMR (400 MHz, CDCl 3 ) δ 7.65 (s, 2H), 7.54 (s, 1H), 7.49-7.40 (m, 3H), 7.35-7.07 (m, 18H), 6.44 (s, 1H), 4.53 (d, J=6.0 Hz, 2H), 4.21 (d, J=15.6 Hz, 3H), 3.71 (s, 2H), 2.50 (s, 3H), 1.50 (d, J=6.7 Hz, 3H).
13 C NMR (100 MHz, CDCl 3 ) δ 180.28 (s), 141.45 (s), 138.82 (d, J=9.8 Hz), 138.30 (d, J=9.8 Hz), 135.78 (d, J=7.7 Hz), 134.88 (d, J=21.3 Hz), 133.42 (dd, J=33.4, 19.7 Hz), 132.53 (d, J=19.5 Hz), 131.28 (q, J=33.4 Hz), 129.43 (s), 129.01-128.44 (m), 128.28 (d, J=6.8 Hz), 128.16 (s), 124.61 (s), 123.89 (s), 121.90 (s), 117.57 (s), 93.41 (d, J=26.4 Hz), 75.47 (d, J=18.1 Hz), 74.42 (s), 73.56 (d, J=5.1 Hz), 73.40 (d, J=4.6 Hz), 72.18 (s), 71.75 (s), 54.83 (d, J=7.7 Hz), 31.93 (s), 15.64 (s).
31 P NMR (162 MHz, CDCl 3 ) δ −18.09 (s), −26.79 (s).
HRMS (ESI): [M+H + ] Calc. 883.1485. found 883.1583.
SI4 was prepared according the according the literature (Zhao, Q., et al., Org. Lett. 2013, 15, 4014-4017). Under an nitrogen atmosphere, 3,5-bis(trifluoromethyl)phenyl isothiocyanate (1.1 mmol) was added to a solution of SI4 (1.0 mmol) in dry DCM (1.0 ml). After the reaction mixture was stirred overnight, the reaction mixture was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (hexane/ethyl acetate=9/1 as eluant) gave L16 as yellow solid.
L16: 1 H NMR (400 MHz, CDCl 3 ) δ 8.07 (s, 1H), 7.75 (d, J=10.5 Hz, 3H), 6.29 (s, 1H), 5.30 (s, 1H), 4.26-4.15 (m, 3H), 4.08 (s, 2H), 4.03 (s, 4H), 1.60 (d, J=6.5 Hz, 3H).
13 C NMR (100 MHz, CDCl 3 ) δ 179.16 (s), 138.72 (s), 133.43 (d, J=33.7 Hz), 124.42 (s), 124.07 (s), 121.36 (s), 119.84 (s), 90.06 (s), 68.59 (d, J=3.6 Hz), 68.27 (s), 67.41 (s), 65.57 (s), 50.14 (s), 19.99 (s). HRMS (ESI): [M + ] Calc. 500.0444. found 500.0452.
SI5 was prepared according the according the literature (Zhao, Q., et al., Org. Lett. 2013, 15, 4014-4017 and Hayashi, T., et al., Bull. Chem. Soc. Jpn, 1980, 53, 1138-1151). Under a nitrogen atmosphere, 3,5-bis(trifluoromethyl)phenyl isothiocyanate (1.1 mmol) was added to a solution of SI5 (1.0 mmol) in dry DCM (1.0 ml). After the reaction mixture was stirred overnight, the reaction mixture was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel (hexane/ethyl acetate=9/1 as eluant) gave L17 as yellow solid.
L17: 1 H NMR (400 MHz, CDCl 3 ) δ 7.74 (s, 3H), 7.51 (s, 2H), 7.40-7.28 (m, 5M), 7.22 (s, 3H), 7.15-7.05 (m, 2H), 5.59 (s, 1H) 4.51 (s, 1H), 4.32 (s, 1H), 3.96 (s, 5H), 3.79 (s, 1H), 1.46 (d, J=4.7 Hz, 3H).
13 C NMR (100 MHz, CDCl 3 ) δ 177.42 (s), 138.02 (s), 137.86 (d, J=6.0 Hz), 134.85 (d, J=4.5 Hz), 133.73 (d, J=20.8 Hz), 131.89 (d, J=33.9 Hz), 131.25 (d, J=17.8 Hz), 128.51 (s), 127.43-127.02 (m), 126.10-125.89 (m), 123.82 (s), 123.27 (s), 120.56 (s), 118.42 (s), 118.01-117.76 (m), 93.98 (d, J=24.2 Hz), 72.16 (s), 71.07 (d, J=4.0 Hz), 70.22 (s), 68.83 (s), 68.66 (s), 50.33 (s), 21.26 (s).
31 P NMR (162 MHz, CDCl 3 ) δ −24.67 (s).
HRMS (ESI): [M+H + ] Calc. 685.0964. found 685.0950.
Example 2—Asymmetric Hydrogenation of Nitroalkenes
In a nitrogen-filled glovebox, a solution of L (2.2 eqv.) and [Rh(COD)Cl] 2 (3.0 mg, 0.006 mmol) in 3.0 mL anhydrous i-PrOH was stirred at room temperature for 30 min. A specified amount of the resulting solution (0.25 mL) was transferred to a vial charged with 1a (0.1 mmol) by syringe. The vials were transferred to an autoclave, which was then charged with 5 atm of H 2 and stirred at 35° C. for 24 h. The hydrogen gas was released slowly and the solution was concentrated and passed through a short column of silica gel to remove the metal complex. The product (2a) was analyzed by NMR spectroscopy for conversion and chiral HPLC for ee values.
(R)-2a: 1 H NMR (400 MHz, CDCl 3 ) δδ 7.38-7.31 (m, 2H), 7.30-7.20 (m, 3H), 4.58-4.46 (m, 1H), 3.85-3.16 (m, 1H), 1.38 (d, J=7.0 Hz, 1H). 13 C NMR (100 MHz, CDCl 3 ) δ 140.93 (s), 128.98 (s), 127.57 (s), 126.90 (s), 81.87 (s), 38.65 (s), 18.73 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=19.4 min, t R (minor)=27.4 min. [α] D 25 =+41.4° (c=0.67, CHCl 3 ).
TABLE 1
Study of effects of pressure, concentration, and temperature. a
Entry
Solvent
Rh-L8
H 2 [atm]
S/C
V (mL)
T [° C.]
2a [%] b
ee [%] c
1
i-PrOH
[Rh(COD)Cl] 2
5
50
0.25
25
>99
99
2
i-PrOH
[Rh(COD)Cl] 2
5
100
0.25
35
>99
99
3
i-PrOH
[Rh(COD)Cl] 2
5
200
0.25
35
97
98
4
i-PrOH
[Rh(COD)Cl] 2
5
400
0.25
35
90
98
5
i-PrOH
[Rh(COD)Cl] 2
10
200
0.25
35
97
99
6
i-PrOH
[Rh(COD)Cl] 2
20
200
0.25
35
>99
98
7
i-PrOH
[Rh(COD)Cl] 2
20
400
0.25
35
95
98
8
i-PrOH
[Rh(COD)Cl] 2
30
400
0.25
35
98
98
9
i-PrOH
[Rh(COD)Cl] 2
5
100
0.5
35
99
98
10
i-PrOH
[Rh(COD)Cl] 2
5
100
1.0
35
97
98
11
i-PrOH
[Rh(COD)Cl] 2
5
400
0.25
45
90
94
a Unless ortherwise mentioned, reactions were performed with 1a (0.1 mmol) and a 1a/Rh/L ratio of 1/1.1/1.1.
b Conversions were determined by 1 H NMR spectroscopy of the crude reaction mixture and HPLC analysis.
c Determined by HPLC analysis on a chiral stationary phase.
β,β-disubstituted nitroalkanes were prepared using the general procedure set forth above with different nitroalkenes. Nitroalkenes with various substituents at the phenyl ring were tolerated. Meta and para substitutions led to excellent results whether they were electron-withdrawing or electron-donating groups. The ortho-methoxy group resulted in a lower conversion and enantioselectivity. This catalytic system also provided enantiomerically β-ethyl nitroalkane with good conversion and excellent enantioselectivity. The nitroalkanes were characterized as follows:
(R)-2b: 1 H NMR (400 MHz, CDCl 3 ) δ 7.39-6.86 (m, 5H), 4.47-4.36 (m, 2H), 3.47-3.49 (m, 1H), 2.25 (s, 3H), 1.28 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 137.87 (s), 137.21 (s), 129.61 (s), 126.73 (s), 81.98 (s), 38.27 (s), 20.98 (s), 18.75 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=14.1 min, t R (minor)=23.0 min. [α] D 25 =+42.9° (c=0.51, CHCl 3 )
(R)-2c: 1 H NMR (400 MHz, CDCl 3 ) δ 7.19-7.11 (m, 2H), 6.96-6.84 (m, 2H), 4.52-4.42 (m, 2H), 3.79 (s, 3H), 3.66-3.54 (m, 1H), 1.35 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 158.94 (s), 132.86 (s), 127.89 (s), 114.34 (s), 82.12 (s), 55.26 (s), 37.92 (s), 18.79 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=22.1 min, t R (minor)=40.6 min. [α] D 25 =+35.8° (c=0.51, CHCl 3 )
(R)-2d: 1 H NMR (400 MHz, CDCl 3 ) δ 7.37-7.27 (m, 2H), 7.21-7.12 (m, 2H), 4.63-4.42 (m, 2H), 3.75-3.48 (m, 1H), 1.37 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 139.35 (s), 133.43 (s), 129.15 (s), 128.27 (s), 81.56 (s), 38.07 (s), 18.71 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=18.8 mm, t R (minor)=27.1 min. [α] D 25 =+39.5° (c=0.48, CHCl 3 )
(R)-2e: 1 H NMR (400 MHz, CDCl 3 ) δ 7.18-7.13 (m, 4H), 4.56-4.43 (m, 2H), 3.70-3.48 (m, 1H), 2.63 (q, J=7.6 Hz, 2H), 1.36 (d, J=7.0 Hz, 3H), 1.22 (t, J=7.6 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 143.58 (s), 138.10 (s), 128.43 (s), 126.83 (s), 82.01 (s), 38.30 (s), 28.42 (s), 18.75 (s), 15.42 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=11.8 min, t R (minor)=19.9 min. [α] D 25 =+54.3° (c=0.44, CHCl 3 ).
(R)-2f: 1 H NMR (400 MHz, CDCl 3 ) δ 7.37-7.32 (m, 2H), 7.18-7.12 (m, 2H), 4.56-4.43 (m, 2H), 3.69-3.51 (m, 1H), 1.37 (d, J=7.0 Hz, 3H), 1.30 (s, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 150.47 (s), 137.79 (s), 126.55 (s), 125.84 (s), 81.97 (s), 38.13 (s), 34.47 (s), 31.29 (s), 18.67 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=9.7 min, t R (minor)=18.4 min. [α] D 25 =+41.8° (c=1.0, CHCl 3 )
(R)-2g: 1 H NMR (400 MHz, CDCl 3 ) δ 7.30-7.22 (m, 1H), 7.16 (dd, J=7.6, 1.6 Hz, 1H), 6.96-6.88 (m, 2H), 4.68 (dd, J=11.9, 6.0 Hz, 1H), 4.46 (dd, J=11.9, 8.8 Hz, 1H), 3.97-3.90 (m, 1H), 3.88 (s, 3H), 1.38 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 157.06 (s), 128.82 (s), 128.51 (s), 127.71 (s), 120.86 (s), 110.83 (s), 80.45 (s), 55.34 (s), 33.48 (s), 17.05 (s). HPLC: OD, 21.5 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=14.4 min, t R (minor)=17.0 min. [α] D 25 =+6.9 (c=0.2, CHCl 3 ).
(R)-2h: 1 H NMR (400 MHz, CDCl 3 ) δ 7.35-7.27 (m, 1H), 7.05-6.87 (m, 1H), 4.57-4.45 (m, 2H), 3.69-3.62 (m, 1H), 1.38 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 164.33 (s), 161.88 (s), 143.46 (d, J=7.0 Hz), 130.57 (d, J=8.3 Hz), 122.65 (d, J=2.9 Hz), 114.59 (d, J=21.0 Hz), 113.96 (d, J=21.8 Hz), 81.51 (s), 38.37 (d, J=1.6 Hz), 18.67 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=20.0 min, t R (minor)=28.4 min. [α] D 25 =+33.3° (c=0.72, CHCl 3 ).
(R)-2i: 1 H NMR (400 MHz, CDCl 3 ) δ 7.31-7.21 (m, 3H), 7.12-7.10 (m, 1H), 4.56-4.45 (m, 2H), 3.70-3.55 (m, 1H), 1.37 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 142.94 (s), 134.83 (s), 130.26 (s), 127.84 (s), 127.17 (s), 125.18 (s), 81.41 (s), 38.33 (s), 18.65 (s). HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=19.8 min, t R (minor)=30.5 min. [α] D 25 =+37.1° (c=0.58, CHCl 3 )
(R)-2j: 1 H NMR (400 MHz, CDCl 3 ) δ 7.26 (t, J=7.9 Hz, 1H), 6.96-6.68 (m, 3H), 4.57-4.44 (m, 2H), 3.80 (s, 3H), 3.66-3.54 (m, 1H), 1.37 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 160.00 (s), 142.54 (s), 130.01 (s), 119.11 (s), 113.10 (s), 112.55 (s), 81.79 (s), 77.34 (s), 77.03 (s), 76.71 (s), 55.23 (s), 38.66 (s), 18.70 (s). HPLC: OD, 215 nm, hexane/2-propanol=95:5, flow rate 0.9 mL/min, t R (major)=29.3 min, t R (minor)=52.2 min. [α] D 25 =+40.6° (c=0.73, CHCl 3 )
(R)-2k: 1 H NMR (400 MHz, CDCl 3 ) δ 8.08-7.70 (m, 3H), 7.67 (d, J=1.0 Hz, 1H), 7.56-7.40 (m, 2H), 7.35 (dd, J=8.5, 1.8 Hz, 1H), 4.67-4.54 (m, 2H), 4.02-3.55 (m, 1H), 1.47 (d, J=7.0 Hz, 2H). 13 C NMR (100 MHz, CDCl 3 ) δ 138.29, 133.52, 132.78, 128.85, 127.76, 127.69, 126.44, 126.08, 125.78, 124.81, 81.80, 38.80, 18.79. HPLC: OD, 215 nm, hexane/2-propanol=80:20, flow rate 0.9 mL/min, t R (major)=19.8 min, t R (minor)=53.5 min. [α] D 25 =+36.8° (c=0.9, CHCl 3 )
(R)-2l: 1 H NMR (400 MHz, CDCl 3 ) δ 7.39-7.23 (m, 3H), 7.21-7.10 (m, 2H), 4.59-4.51 (m, 2H), 3.54-3.11 (m, 1H), 1.79-1.66 (m, 2H), 0.84 (t, J=7.4 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 139.33, 128.89, 127.56, 80.76, 46.00, 26.18, 11.49. HPLC: OD, 215 nm, hexane/2-propanol=98:2, flow rate 0.9 mL/min, t R (major)=16.0 min, t R (minor)=27.7 min. [α] D 25 =+35.5° (c=0.54, CHCl 3 )
(S)-2m: 1 H NMR (400 MHz, CDCl 3 ) δ 6.26-6.23 (m, 1H), 6.05 (d, J=3.1 Hz, 1H), 4.59 (dd, J=12.2, 6.6 Hz, 1H), 4.36 (dd, J=12.2, 8.0 Hz, 1H), 3.72-3.60 (m, 1H), 1.31 (d, J=7.0 Hz, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 152.85 (s), 141.08 (s), 109.27 (s), 104.92 (s), 78.49 (s), 31.41 (s), 15.12 (s). HPLC: OD, 215 nm, hexane/2-propanol=99.5:0.5, flow rate 0.9 mL/min, t R (major)=27.5 min, t R (minor)=30.7 min.
Example 3—Asymmetric Hydrogenation of N—H Imines
All N—H imines were prepared according the literature (Hou, G., et al., J. Am. Chem. Soc. 2009, 131, 9882-9883.). All the spectral data are consistent with the literature values.
1 H NMR (400 MHz, CDCl 3 ) δ 11.46 (s, 2H), 8.20-7.91 (m, 2H), 7.78 (t, J=7.5 Hz, 1H), 7.61 (dd, J=17.7, 9.6 Hz, 2H), 2.94 (d, J=5.2 Hz, 3H).
13 C NMR (100 MHz, CDCl 3 ) δ 186.36 (s), 136.95 (s), 129.92 (s), 129.35 (s), 129.33 (s), 21.73 (s).
General Procedure:
In a nitrogen-filled glovebox a solution of L14 (2.2 eqv.) and [Rh(COD)Cl] 2 (3.0 mg, 0.006 mmol) in 6.0 mL anhydrous i-PrOH was stirred at room temperature for 30 min.
A specified amount of the resulting solution (1 mL) was transferred to a vial charged with 1a (0.1 mmol) by syringe. The vials were transferred to an autoclave, which was then charged with 10 atm of H 2 and stirred at 25° C. for 24 h. The resulting mixture was concentrated under vacuum and dissolved in saturated aqueous NaHCO 3 (5 mL). After stirring for 10 min, the mixture was extracted with CH 2 Cl 2 (3×2 mL) and dried over Na 2 SO 4 . To the resulting solution was added Ac 2 O (300 μL) and stirred for 30 min. The resulting solution was then analyzed for conversion and ee directly by GC. The product was purified by chromatography on silica gel column with dichloromethane/methanol (90:10). All spectral data were consistent with the literature values (Hou. G., et al., J. Am. Chem. Soc. 2009, 131, 9882-9883).
TABLE 2
Study of metal salts.
H 2
Conv.
ee
Entry
Solvent
Metal
[atm]
S/C
V [mL]
T [° C.]
[%] b
[%] c
1
i-PrOH
[Rh(COD)Cl] 2
20
25
1
35
99
92
2
i-PrOH
[Ir(COD)Cl] 2
20
25
1
35
90
84
3
i-PrOH
Rh(COD) 2 BF 4
20
25
1
35
93
77
4
i-PrOH
Rh(NBD) 2 SbF 6
20
25
1
35
95
17
5
i-PrOH
Pd(OAc) 2
20
25
1
35
<1
ND
6
i-PrOH
Pd(TFA) 2
20
25
1
35
30
0
7
i-PrOH
[{RuCl 2 (p-cymene)} 2 ]
20
25
1
35
8
23
[a] Unless ortherwise mentioned, reactions were performed with 1a (0.1 mmol) and a Metal/L14 ratio of 1/1.1.
b Determined by GC analysis of the corresponding acetamides.
ND = not determined.
TABLE 3
Study of pressure and temperature.
Conv.
Entry
Solvent
H 2 [atm]
S/C
V (mL)
T [° C.]
[%] b
ee [%] c
1
i-PrOH
20
25
1
35
99
92
2
i-PrOH
20
50
1
35
99
93
3
i-PrOH
20
100
1
35
99
93
4
i-PrOH
10
100
1
25
99
94
5
i-PrOH
10
200
1
25
96
94
6
i-PrOH
10
400
1
25
86
93
7
i-PrOH
20
200
1
25
97
93
8
i-PrOH
20
200
1
35
97
92
9
i-PrOH
20
400
1
35
90
93
[a] Reactions were performed with 1a (0.1 mmol) and a [Rh(COD)Cl] 2 /L14 ratio of 1/1.1.
b Determined by GC analysis of the corresponding acetamides.
TABLE 4
Study of additives.
H 2
Conv.
Entry
Solvent
[atm]
S/C
Additive
T [° C.]
[%] b
ee [%] b
1
i-PrOH
20
50
4A MS
35
67
53
(100 mg)
2
i-PrOH
20
50
CF 3 COOH
35
99
75
(10 mmol %)
3
i-PrOH
20
50
CH 3 COOH
35
98
79
(10 mmol %)
4
i-PrOH
20
50
Et 3 N
35
63
35
(10 mmol %)
[a] Reactions were performed with 1a (0.1 mmol) and a [Rh(COD)Cl] 2 /L14 ratio of 1/2.2.
b Determined by GC analysis of the corresponding acetamides.
TABLE 5
Solvent study.
Entry
Solvent
Metal source
Covn. b (%)
ee b (%)
1
i-PrOH
[Rh(COD) 2 ]BF 4
93
77
2
i-PrOH
[Rh(NBD) 2 ]SbF 6
95
47
3
i-PrOH
[Rh(COD)Cl] 2
99
92
4
CH 2 Cl 2
[Rh(COD)Cl] 2
91
30
5
Toluene
[Rh(COD)Cl] 2
60
15
6
THF
[Rh(COD)Cl] 2
76
60
7
MeOH
[Rh(COD)Cl] 2
99
73
8
EtOH
[Rh(COD)Cl] 2
92
89
9
t-BuOH
[Rh(COD)Cl] 2
84
91
10 c
i-PrOH
[Rh(COD)Cl] 2
99
93
11 d
i-PrOH
[Rh(COD)Cl] 2
99
94
12 e
i-PrOH
[Rh(COD)Cl] 2
96
94
11 f
i-PrOH
[Rh(COD)Cl] 2
97
93
14 g
i-PrOH
[Rh(COD)Cl] 2
97
92
a Unless otherwise mentioned, reactions were performed with 1a (0.1 mmol) and a Rh/L/1a ratio of 1/1.1/25 in 1.0 mL solvent at 35° C. under 20 atm H 2.
b Determined by GC analysis of the corresponding acetamides.
c S/C = 100, 35° C., 20 atm H 2 .
d S/C = 100, 25° C., 10 atm H 2 .
e S/C = 100, 25° C., 10 atm H 2 .
f S/C = 200, 25° C., 20 atm H 2 .
g S/C = 200, 35° C., 20 atm H 2 .
COD = 1,5-cyclooctadiene, NBD = 2,5-norbornadiene.
A variety of N—H imines were tested. Most substrates with meta and para substitutions on the phenyl ring afforded high yields and enantioselectivities (96-99% yield and 90-94% ee).
However, the chloro group and methoxy group resulted in an obvious decrease of the yields (2d, 2e and 2g). The ortho-methoxy group on the phenyl ring resulted in 34% yield and 84% ee (2h). Products with 1- and 2-naphthyl group were obtained with 92% ee and 93% ee respectively. Changing the R 2 group had a significant effect on the outcome. When R 2 was ethyl, both lower conversion and enantioselectivity were observed (2k). As the R 2 group was changed to butyl, further loss of the conversion and enantioselectivity was observed (70% yield and 75% ee, 2l).
To obtain insight into this catalytic system, a series of chiral ligands were prepared and control experiments were undertaken.
TABLE 6
Ligand study.
Entry
Ligands
Covn. b (%) b
ee b (%)
1
L1
2
55
2
L2
22
66
3
L3
6
11
4
L4
72
87
5
L5
76
90
6
L6
99
94
7
L7
26
38
8
L8
2
11
9
L9
9
84
10 c
L8
5
8
11 d
L1
9
57
a Unless otherwise mentioned, reactions were performed with 1a (0.1 mmol) and a Rh/L/1a ratio of 1/1.1/100 in 1.0 mL solvent at 25° C. under 10 atm H 2 .
b Determined by GC analysis of the corresponding acetamides.
c Rh/L/1a/Ph 3 P = 1/1.1/100/2.2.
d Rh/L/1a/thiourea = 1/1.1/100/1.1.
The Rh-bisphosphine complex without a (thio)urea (L9) showed very low activity and enantioselectivity (Table 6, entry 1). Urea L10 provided 22% conversion and 66% ee in sharp contrast with the more acidic thiourea L14 (Table 6, entry 2 vs. 6). 1a The CF 3 group on the 3,5-(trifluoromethyl)phenyl moiety remained important in the catalytic system (Table 6, entries 3-5). Further, several modified ligands were prepared and screened. An N-methylation of L14 led to a dramatic decrease of the conversion and enantioselectivity (Table 6, entry 7). This finding suggested that the NH was involved in the activation of iminium salts and the stereoselectivity of hydrogenation. Furthermore, the low conversion and enantioselectivity obtained with monodentate phosphorus ligands implied that a bisphosphine moiety was essential (Table 6, entry 9). Importantly, neither the combination of the chiral phosphine with the 3,5-bistrifluoromethylphenyl thiourea, nor the combination of the chiral thiourea with the simple phosphine improved this reaction (Table 6, entry 1 vs. 11, entry 8 vs. 10), which pointed to the importance of the covalent linker for high activity and enantioselectivity.
Different counterions and additives were also investigated. When the chloride counterion in 1a was replaced with trifluoromethanesulfonate, only 20% conversion and 53% ee was observed (Table 7, entry 1). The addition of a chloride counterion increased the conversions and enantioselectivities (entries 2 and 3). However, the addition of bromide and iodide counterions decreased the conversions and enantioselectivities (entries 4-6).
TABLE 3
Substrates study and control experiments. a
Entry
1
Additive
Conv. b (%)
ee b (%)
1
1m
—
20
53
2
1m
TBAC
86
94
3
1m
LiCl
71
93
4
1a
—
99
94
5
1a
TBAB
77
90
6
1a
TBAI
32
89
a Unless otherwise mentioned, reactions were performed with 1a (0.1 mmol) and a Rh/L/1a/Additive ratio of 1/1.1/100/100 in 1.0 mL solvent.
b Determined by GC analysis of the corresponding acetamides.
c Determined by 1 H NMR.
TBAC = tetrabutylammonium chloride,
TBAB = tetrabutylammonium bromide,
TBAI = tetrabutylammonium iodide.
ND = not detertimined.
Further information about the reaction was obtained by 1 H NMR studies of mixtures generated from ligands and TBAC. The addition of varying amounts of TBAC to L14 in CDCl 3 resulted in downfield shifts of the NH proton signals. At 1.0 equivalents of TBAC, the signal for NH was at 9.73 ppm, but when 3.0 equivalents of TBAC were added, the NH signal appeared at 10.16 ppm. Analogous experiments employing a series of different ligands and TBAC gave similar results. This finding was consistent with a hydrogen-bonding interaction between the catalyst's thiourea and chloride ions. This observation, coupled with the fact that optimal yields and ee values involve chloride ions, led us to propose that catalytic chloride-bound intermediates are involved in the mechanism.
The present invention has been described with particular reference to the preferred embodiments. It should be understood that the foregoing descriptions and examples are only illustrative of the invention. Various alternatives and modifications thereof can be devised by those skilled in the art without departing from the spirit and scope of the present invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications, and variations that fall with the scope of the appended claims. | A ligand having the structure or its enantiomer; (I) wherein: each one of R a , R b , R c and R d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH 2 NH; *CH(CH 3 )NH(C*,R); and the organocatalyst is an organic molecule catalyst covalently bound to the bridge group. Also, a catalyst having the structure or its enantiomer: (II) wherein: each one of R a , R b , R c and R d is selected from alkyl, cycloalkyl, and aryl; the bridge group is selected from CH 2 NH; *CH(CH 3 )NH(C*,R); and *CH(CH 3 )NH(C*,S); the organocatalyst is an organic molecule catalyst covalently bound to the bridge group; and M is selected from the group consisting of Rh, Pd, Cu, Ru, Ir, Ag, Au, Zn, Ni, Co, and Fe. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
A Continuation-In-Part of U.S. Pat. No. 6,764,108, issued Jul. 20, 2004, which is a Continuation-In-Part of U.S. application Ser. No. 09/679,359, filed Oct. 5, 2000, now abandoned, which claims priority of Argentina P99 01 06162, filed Dec. 3, 1999.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an elongated assembly of hollow, torque transmitting pumping rods, used to selectively rotate a rotary pump located deep down hole in an oil well from a drive head located at the surface of the oil well A pumping rod assembly or sucker rod string is significantly distinguished in the art by the fact that such a string is not typically undergoing substantially free rotation like a drill pipe string, but rather is a true drive shaft that stores large amounts of reactive torque due to its large length, typically between 1,500 to 6,000 feet. The present invention comprises individual elements referred to herein as a “Hollow Sucker Rod” with at least a first end having a female thread and a “Connecting Element” which may be a separate “Nipple Connecting Element” with a pair of male threads or an integral male thread on a second, upset end of a Hollow Sucker Rod.
2. Description of the Related Art
Non-surging oil well extraction is normally achieved by means of pumping systems. The most common system uses an alternating pump located at the bottom of the well driven by a sucker rod string that connects the bottom of the well with the surface, where an alternating pumping machine to drive the string up and down is located. The sucker rods in the prior art, therefore, were designed originally to simply reciprocate up and down, and were are manufactured to API Specification 11B using solid steel bars with an upset end and a threaded end, each thread being of solid cylindrical section. The rods typically were connected one with the other by means of a cylindrical threaded coupling. More efficient pumping is performed when an oil extracting progressive cavity pump (PCP), or like rotary down hole pump is used. Among other advantages, PCP pumping of oil allows for higher oil extraction rates, reduced fatigue loads, reduction in wear on the inside of production tubing, and the ability to pump high viscosity and high solids component oils. PCP pumps are installed at the bottom of the well and driven from the surface by an electric motor connected to a speed-reducing gearbox by means of a string of torque transmitting rods. Traditionally standard API sucker rods are used to drive PCP pumps notwithstanding the fact that these rods have not been designed to transmit torsional loads. The transmission of torque by means of sucker rod strings presents the following disadvantages, i) low torque transmitting capacity, ii) high backspin iii) big stiffness differential between the connection and the rod body, all factors that enhance the possibility of fatigue failures. The reason for rupture on this type of conventional rod is failure due to fatigue in the junction zone of the head of the rod with the body of same due to the difference in structural rigidity between both parts—the body of the rod and the head of the rod.
For a given cross sectional area, torque transmission by a hollow rod with an annular cross section is more efficient than with a narrower, solid circular cross section. With the above mentioned concept in mind the prior art includes a hollow sucker rod that simply uses a standard API external cylindrical thread on a first end connector and an internal API thread on a second end connector, each connector being butt welded to a pipe body, which creates significant and abrupt change in section between the pipe body and each connection body. (See Grade D Hollow Sucker Rod, CPMEC Brochure, undated). The problem of sucker rod string backspin, and details of a drive head at the surface of an oil well and a rotary pump deep down hole in an oil well operation, which is the specific field of invention being addressed herein, can be found in Mills (U.S. Pat. No. 5,551,510), which is incorporated herein by reference.
Various thread and shoulder arrangements are discussed in the prior art with respect to joining together oil well drill pipe, well casing and tubing. See, for example, Pfeiffer et al. (U.S. Pat. No. 4, 955,644); Carstenson (U.S. Pat. No. 5,895,079), Gandy (U.S. Pat. No. 5,906,400), Mithoff (U.S. Pat. No. 262,086), Blose (U.S. Pat. No. 4,600,225), Watts (U.S. Pat. Nos. 5,427,418; 4,813,717; 4,750,761), Schock et al. (U.S. Pat. No. 6,030,004), and Hardy et al. (U.S. Pat. No. 3,054,628). The Watts patents imply that a pre-1986 API standard for strings of casing and tubing was a straight thread, with a turned down collar and that his improvement comprised a flush joint tubular connection with both tapered threads and a shoulder torque. Watts also refer to API standards for tubing and casing where triangular and buttress threads can be used with a torque shoulder. The 1990 patent to Pfeiffer et al, and the 1996 patent to Carstensen et al, in contrast, refer to a more current API standard (truncated triangular thread, connection using a torque shoulder) for strings of casing and tubing that appears to involve frusto-conical threads and shoulders. Carstensen et al at col 7, line 9+ include a discussion about how a particular conical gradient and length of a thread defines stress distribution results. Likewise, Pfeiffer et al at col 2, line 51+ say their threads are tapered and according to “API standards” with their improvement essentially only having to do with transitional dimensions. Hence, the problem addressed by Pfeiffer is an assembly of drill pipe sections where it apparently was critical to use a compatible and standard non-differential thread according to API standards, and also with no incomplete threads and no torque shoulder specification. The main features of the Pfeiffer thread appear to be symmetrical, truncated triangle threads (between 4 and 6 threads per inch, 60° flank angle) and a thread height that is the same for the male and female thread (between 1.42 and 3.75 mm). Also, there is identical nominal taper on male and female ends (between 0.125 and 0.25). Shock et al. illustrate a particular tool joint for drill pipe where the unexpected advantage for drill pipe applications derives from tapered threads that significantly must be very coarse (3 ½ threads per inch) and have equal angle (75°) thread flanks and elliptical root surfaces.
However, the different problem of backspin inherent in the intermittent operation of a sucker rod string when driving a PCP pump is not apparently addressed in any of these references. The design of the invention was made with certain specific constraints and requirements in mind.
First, the minimum diameter of the tubings on the inside of which the Hollow Rods must operate corresponds to API 2⅞″ tubing (inner diameter=62 mm) and API 3½″ tubing (inner diameter=74.2 mm). The oil extraction flow rate must be up to 500 cubic meters per day, maximum oil flow speed must be 4 meters per second. The above-mentioned values strongly restrict the geometry of the rods under design. Second, to ensure a Hollow Rod with a high yield torque so that maximum torque is transmitted to the PCP pump without damage to the Hollow Rod string. Third, to minimize and distribute stresses in the threaded sections. This requirement is met by using a particular conical thread, differential taper, low thread height and a conical bore in the sections under the threads. Fourth, the Hollow Sucker Rod must have good fatigue resistance. Fifth, to ensure low backspin, and high resistance to axial loads. Sixth, ease of make up and break out (assembly of mating threaded parts) must be ensured, and is by a tapered thread. Seventh, to ensure high resistance to unscrewing of the Hollow Sucker Rod due to backspin, or the counter-rotation of a sucker rod string when driving motor stops running and the pump acts as a motor. Eighth, to ensure high resistance to jump out of the Hollow Sucker Rod string (Hollow Rod parting at the threaded sections) by means of adequate thread profile and reverse angle on the torque shoulder. Ninth, to minimize head loss of the fluids that occasionally can be pumped on the inside of the Hollow Sucker Rod through the added advantage of a conical bore on the nipple. Tenth, to ensure connection sealabilty due to sealing at the torque shoulder, and also due to diametrical interference at the threads. Eleventh, a thread profile designed so as to optimize pipe wall thickness usage. Twelfth, to eliminate use of the welds due to susceptibility of welds to fatigue damage, sulphide stress cracking damage and also the higher costs of manufacturing. Thirteenth, when a fluid flows through the interior of the rod with reasonable speed, it produces early wear of the nipple and rod in the area where they connect (overlap), hence, a small seal was introduced at the ends of the nipple.
Fourteenth, to substantially increase the flow of fluid extracted, holes in the rod body were drilled to allow the fluid flowing through the interior of the rod.
A first object of the present invention is to provide an assembly of sucker pump rods and either separate threaded unions, or an integral union at the second end of each sucker rod, to activate PCP and like rotary type pumps, capable of transmitting greater torque than the solid pump rods described in the API 11 B Norm and also possessing good fatigue resistance. Additionally, the present invention seeks to define a threaded union for hollow rods that is significantly different from, and incompatible with, the standard for sucker rod assemblies as defined in the API 11 B Norm, yet still can easily be assembled. In fact the modified buttress thread is unique in that it is differential. For example, API Buttress Casing requires non-differential threads, with the taper for both a pipe and a coupling being 0.625 inches/inch of diameter. Likewise, API 8r casing and API 8r tubing both also require non-differential threads, with the taper for both a pipe and a coupling being 0.625 inches/inch of diameter. Still further, each of API Buttress Casing, API 8r casing and API 8r tubing do not employ any manner of torque shoulder.
A related object of the present invention is to provide an assembly of pump rods and unions with lesser tendency to uncoupling of the unions whenever “backspin” occurs, whether by accident or when intentionally provoked by the deactivation of the pump drive. The present invention surprisingly and significantly decreases the stored torsional energy in a sucker rod string. The stored energy in the string is inversely proportional to the diameter of the rod, and is directly proportional to the applied torque and the length of the string.
Another object of the invention is to provide for an assembly of sucker rods which are hollow and configured with a bore to permit passage of tools (sensors for control of the well) and/or allow interior circulation of fluids (injection of solvents and/or rust inhibitors).
Other objects of the present invention are to solve the corrosion-erosion probem, by a small seal introduced at the ends of the nipple, with a corresponding modification of the angle of the internal conical bore and to substantially increase the flow of fluid extracted, with holes in the rod body at extreme ends of the string.
SUMMARY OF THE INVENTION
The present invention addresses the foregoing needs in the art by providing a new type of Hollow Sucker Rod consisting essentially of a pipe central section, with or without an upset, with at least one internal or female conical thread at a first end having a thread vanishing on the inside of the rod and a conical external torque shoulder. That first end is configured to engage a corresponding external or male thread that is differential and also to abut against a conical torque shoulder on either another rod with an externally threaded integral Connecting Element as its second end, or one of the shoulders between the external threads of a separate Nipple Connecting Element. If separate Nipple Connecting Elements are used, then the sucker rod second end is always the same as the first end. If separate Nipple Connecting Element are not used, then the sucker rod second end is configured with an upset end having a male conical thread adapted to engage the first end of another Hollow Sucker Rod.
A Nipple Connecting Element consists essentially of a central cylindrical section with a pair of conical external torque shoulders. The torque shoulders have a maximized mean diameter and cross-sectional area to resist storing reactive torque in the drive string. The nipple preferably also has a wall section that increases towards the torque shoulders from each free end to increase fatigue resistance. In order to further optimize the stress distribution between the elements, a specific type of thread with a differential taper is used. The overall configuration ensures high shear strength, lowered stress concentration and a surprising resistance to storing reactive torque, which minimizes dangerous backspin when power to the sucker rod string is interrupted.
The Nipple Connecting Element member also has trapezoidal, non-symmetric male threads at each end or extreme, separated by a pair of shoulder engaging elements, but that male thread is differential as to the diametral taper of the female thread on at least the first end of a Hollow Sucker Rod. The threaded nipple and the rod can be joined with or without discontinuity of outer diameter. The ratio of the diameter of the union to the diameter of the rod may between 1 without discontinuity of diameters, to a maximum of 1.5. In this manner the mean value of the external diameter throughout the length of the string will always be greater to that of a solid rod with equivalent cross-sectional area mated to a conventional union means. Hence, for a given length of string and cross-sectional area, resistance to “backspin” will be greater in an assembly according to the present invention. The dimensions of the nipple also may be defined with a conical inner bore proximate the length of each threaded extreme, to further enhance an homogenous distribution of tensions throughout the length of each thread and in the central body portion of the Nipple Connecting Element. In this way it is possible to obtain a desired ratio of diameters of the threaded ending of the nipple with respect to the internal diameter, and a ratio of outside diameter of the nipple with respect to the internal diameter and an additional ratio between the external diameter of the nipple and the diameter of each threaded extreme.
In a first object of the present invention, the essential characteristic of a Hollow Sucker Rod is at least a first end of a tubular element threaded with a conical female thread which is configured as a Modified Buttress or SEC thread and vanishes on the inside of the tubular element, in combination with a conical frontal surface at an angle between 75° and 90°, known as a torque shoulder. The external diameter of the HSR 48×6 External Flush and the HSR 42×5 Upset embodiments comprise a tubular rod body element away from the ends being 48.8 mm or 42 mm and the external diameter of the tubular element in the upset end of a 42 mm rod being 50 mm. These dimensions are critical since sucker rods of that maximum diameter can fit within standard 2⅞ inch tubing (62 mm inside diameter). For 3½ inch tubing (74.2 mm inside diameter) the HSR 48×6 Upset, with a diameter at the upset end of 60.6 mm, can be used for maximum advantage. The thread shape is trapezoidal and non-symmetric, with a Diametrical taper in the threaded section. The Length of threads on at least the first end of the tubular element are incomplete due to vanishing of thread on the inside of the tubular element. There is an 83° angle (Beta) of the conical surface in the torque shoulder as shown in FIG. 2A . There are radii at the inner and outer tips of the torque shoulder. At the end of the threaded section a short cylindrical section on the inside of the threaded area transitions the threaded area to the bore of the tubular element.
In a first object of the present invention, the essential characteristic of a Nipple Connecting Element is a differential thread engagement on either side of a central section that is externally cylindrical with a larger cross-sectional area in the vicinity of the torque shoulder for surprisingly improved fatigue resistance. At either side of this central section external torque shoulders are located to mate with a torque shoulder on a first end of a Hollow Sucker Rod. The mean diameter and total cross-sectional area of the torque shoulder is maximized, to allow maximum torque handling.
In addition, either end of the nipple externally threaded is conical so to create a larger cross-sectional area in the vicinity of the torque shoulder and thereby surprisingly improve fatigue resistance. To achieve this advantage a narrowing conical inner bore starts proximate the free end of each threaded extreme and thereby defines an increasing wall thickness cross-section towards the central section of the nipple. The external diameter of the central section of the nipple is 50 mm or 60.6 mm and that central section may have a pair of machined diametrically opposite flat surfaces, to be engaged by a wrench during connection make up. The thread is a Modified Buttress thread, which creates a differential due to slightly different amounts of diametral thread taper on the rod and on the nipple. The thread shape also is trapezoidal and non-symmetric. All threads on the nipple are complete. A pair of conical surface act as torque shoulders with a conical frontal surface at an angle between 75° and 90°. There are radii at tips of the torque shoulder, both at an inner corner and an outer corner. Preferably, conical bores under each threaded section of the nipple are connected by a cylindrical bore to create a larger cross-sectional area in the immediate vicinity of the torque shoulder in order to surprisingly improve fatigue resistance.
The thread taper on the nipple and on the rod is slightly different (Differential Taper) to ensure optimal stress distribution. When the connection is made up the corresponding torque shoulders on the rod and on the nipple bear against each other so that a seal is obtained that precludes the seepage of pressurized fluids from the outside of the connection to the inside of said and vice-versa. This sealing effect is enhanced by the diametrical interference between the two mating threaded sections on the first end of the rod and on the nipple.
A fluid flowing through the interior of the rod with reasonable speed tends produce early wear of the nipple and rod in the area where they connect (overlap). This phenomenon can be attributed to the existence of an “stagnation area” where the fluids remains almost still (low velocity). To overcome that corrosion problem the invention includes modifications so that the “stagnation zone” does not exist any more and the fluid flows smoothly and with little turbulence. It is important to note that these modifications are small so that they do not alter significantly the stress distribution in the connection or the performance of the nipple.
In yet other set of embodiments, the objective is to substantially increase the flow of fluid extracted, through a further modification to a hollow sucker rod by drilling a series of holes in the rod at the two extremes of the string, i.e., at the ground level and at the bottom of the well.
A better understanding of these and other objects, features, and advantages of the present invention may be had by reference to the drawings and to the accompanying description, in which there are illustrated and described different embodiments of the invention. All of the embodiments are considered exemplary of parts of a preferred assembly embodiment, since any one of the illustrated male ends will successfully mate with any one of the illustrated female ends.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B , represent a Prior Art configuration of a conventional solid sucker rod as established in the API 11 B Norm specification.
FIGS. 2A , 2 B and 2 C respectively represent general configurations of a Hollow Sucker Rod first end, a Nipple Connecting Element, and an assembly of both elements according to a first embodiment of the invention, with a constant outer diameter.
FIG. 3A represents a general configuration of the assembly of a Hollow Sucker Rod having first and second female threaded ends and a Nipple Connecting Element according to a second embodiment of the invention, with an upset end, or an enlarged outer diameter.
FIG. 3B represents a general configuration of the assembly of a Hollow Sucker Rod having a first female threaded end and a second end with a male threaded end according to a third embodiment of the invention, with a constant outer diameter.
FIGS. 4A , 4 B and 4 C respectively represent an axial section view, a shoulder detail view and a cross-section view along Line 4 C— 4 C of a Nipple Connecting Element having first and second male threaded ends, according to a fourth embodiment of the invention, styled Hollow Rod 48×6 External Flush.
FIGS. 5A and 5B respectively represent an axial section view and a shoulder detail view of a Hollow Sucker Rod having a first female threaded end, according to the fourth embodiment of the invention.
FIGS. 6A , 6 B and 6 C respectively represent an axial section view, a cross-section view along Line 6 B— 6 B and a shoulder detail view of a Nipple Connecting Element having first and second male threaded ends, according to a fifth embodiment of the invention, styled Hollow Rod 42×5 External Upset.
FIGS. 7A and 7B respectively represent an axial section view and a shoulder detail view of a Hollow Sucker Rod having a first female threaded end, according to the fifth embodiment of the invention.
FIGS. 8A , 8 B and 8 C respectively represent an axial section view, a shoulder detail view and a cross-section view along Line 8 B— 8 B of a Nipple Connecting Element having first and second male threaded ends, according to a sixth embodiment of the invention, styled Hollow Rod 48.8×6 External Upset.
FIGS. 9A and 9B respectively represent an axial section view and a shoulder detail view of a Hollow Sucker Rod having a first female threaded end, according to the sixth embodiment of the invention.
FIG. 10A represents an axial section view and dimension detail view of a first female threaded end on a Hollow Sucker Rod showing the configuration of a trapezoidal, non-symmetric thread profile that is a Modified Buttress or SEC thread, according to the preferred embodiments of the invention.
FIG. 10B represents an axial section view and dimension detail view of a first male threaded end on a Nipple Connecting Element showing the configuration of a trapezoidal, non-symmetric thread profile that is a Modified Buttress or SEC thread, according to the preferred embodiments of the invention.
FIG. 11 illustrates an axial section view of an external flush joint, with Zone A indicating a stagnation zone.
FIG. 12 illustrates corrosion in a stagnation zone.
FIG. 13 illustrates an axial section view of a modified external flush joint, with a modified nipple.
FIG. 14 illustrates an axial section view of a modified nipple, as in FIG. 13 .
FIG. 15 illustrates an axial section view of a modified rod, as in FIG. 13 .
FIGS. 16A and 16B illustrate an axial and section view of one extreme end of a modified rod, according to a Configuration 1;
FIGS. 17A and 17B illustrate an axial and section view of one extreme end of a modified rod, according to a Configuration 2; and
FIGS. 18A and 18B illustrate an axial and section view of one extreme end of a modified rod, according to a Configuration 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1A represents a common solid sucker rod with its conventional threaded first end or head with a cylindrical-type male thread. A large discontinuity between the head of the rod and the body of the rod can easily be seen. Diameters DC and DV, respectively. FIG. 1B is a schematic of the assembly of that solid pump rod with a conventional threaded union or collar according to the API 11 B Norm.
FIGS. 2A–2C respectively represent general configurations of a Hollow Sucker Rod first end, a Nipple Connecting Element, and an assembly of both elements according to a first embodiment of the invention, with a constant outer diameter. FIG. 2A gives references at the female extreme of the hollow rod according to the invention. It is also possible to observe the frustro-conical shape threaded surface in the interior of the rod that diminishes in the internal diameter thereof. FIG. 2B gives references at the nipple or union according to the present invention. The external thread of frustro-conical shape and the presence of two torque shoulders can also be seen. It is also possible to observe the varying of the nipple inner bore diameter with conical shape labeled “Option A”, as indicated by a broken line, which in turn creates a larger cross-sectional area in the vicinity of the torque should and surprisingly improves fatigue resistance.
FIG. 2C gives further references for the assembly of two hollow pump rods and one threaded union. It can be observed that the two female threads in the internal diameter of rod ( 3 . a and 3 . b ) are joined to the corresponding male ends ( 1 . a and 1 . b ) and how torque shoulders ( 2 . a and 2 . b ) are part of nipple ( 2 ). The union between the corresponding male and female extremes is accomplished by differential engagement of the frustro-conical shape of the threads ( 5 . a and 5 . b ). The fact that the thread shape is frustro-conical facilitates the initial setting of each piece and assembly of both parts. Shoulders located at the extreme free end surfaces of the first and second ends of the hollow rods ( 4 . a and 4 . b ) engage, in the assembled position, against a pair of corresponding torque shoulders formed on the nipple ( 2 . a and 2 . b ). Said contact planes form a torque shoulder angle (angle “Beta” see FIG. 2A ) with respect to the axis of the rod, which angle being between 75° and 90° and most preferably being 83°.
FIG. 2B shows in general geometry references for a connecting element as a separate nipple and specifically defines outside diameter (DEN), internal diameter (DIN) and the start diameter of the torque shoulder (DHT). The connecting element for the invention is characterized by the ratios of diameters according to the following table:
Range
Diameter Ratios
Min.
Max.
DHT/DEN
0.60
0.98
DIN/DEN
0.15
0.90
DIN/DHT
0.25
0.92
FIG. 2B also illustrates, by the broken line, a conical bore option, Option A, for the nipple inner bore configuration, which is preferred. FIG. 2A shows the hollow rod in the union zone with an outside diameter (DEVU) and an internal diameter of the rod at the extreme surfaces of the first and second ends corresponding to the end of the thread (DIFR). It also shows the outside diameter of the hollow rod (DEV) labeled as DEVU=DEV, because there is no upset end acting as the union. The ratio of the maximum external diameter (DEVU), either of a separate connector element or the upset type end of integral connector element union, to the external diameter of the rod (DEV), as illustrated at FIGS. 3A , 7 A and 9 A, is maintained within the following range:
1 ≤ DEVU DEV ≤ 1.5
Hence for a maximum fixed diameter, the mean polar momentum of the hollow rod and connector string is greater than that for a solid pump rod of equal cross section diameter. Transmitted rotation moment or torque is therefore greater in a hollow rod column than in a solid rod column. This is also a determining factor in the resistance to the “backspin” phenomenon or counter-rotation of the rod string. Additionally, the ratio between the starting diameter of the torque shoulder on the connecting element (DHT) and the internal diameter of the hollow rod at the thread free end (DIFR), is maintained, as follows:
1 ≤ DIFR DHT ≤ 1.1
FIG. 3A gives further references at the assembly in which the ratio of the maximum diameter of the union (DEVU) to the diameter of the body of the rod (DEV) is limited (1<DEVU/DEV≦1.5). FIG. 3B is a possible configuration of the invention in which the female thread is machined on an upset first end of the rod, while the opposite or second end is machined with a corresponding male thread, the two threads being complementary but differential in diametral taper to each other. This configuration will be referred to as an upset rod, or as an integral union version.
FIGS. 4–10 , inclusive, relate to preferred embodiments where a Hollow Sucker Rod comprises at least a first end of a tubular element threaded with a conical female thread which is configured as a Modified Buttress or SEC thread and which vanishes on the inside of the tubular element, in combination with a torque shoulder angle (Beta) of between 75° and 90°. The external diameter of the tubular element away from the ends being either 42 mm or 48.8 mm and the external diameter of the tubular element in the upset end, if present, being either 50 or 60.6 mm.
FIGS. 4A , 4 B and 4 C respectively represent an axial section view, a shoulder detail view and a cross-section view along Line 4 C— 4 C of a Nipple Connecting Element 402 with a flat 406 having first and second male threaded ends, 401 .and 401 . b , according to a fourth embodiment of the invention, styled Hollow Rod 48×6 External Flush. In FIG. 4A the values are a Modified SEC thread 405 . b, 8 threads per inch; DEN=48.8 mm; DIN=20 mm with an expansion to 26 mm over a length of 44 mm to the extreme end; DHT=39 mm; Beta=83°; overall length=158 mm; thread length=46 mm and central section length=50 mm. The shoulder detail 402 . a in FIG. 4B begins 4.61 mm after the thread, has an inner radius of 1.4 mm and an outer shoulder radius of 0.5 mm.
FIGS. 5A and 5B respectively represent an axial section view and a shoulder detail view of a Hollow Sucker Rod 403 having a first female threaded end 403 . a , according to the fourth embodiment of the invention. In FIG. 5A the values are a Modified SEC thread 405 . a, 8 threads per inch; DEV=48.8 mm; DIFR=41.4 mm; DIV=37 mm; Beta=83°. The shoulder detail 404 . a in FIG. 5B has a 30° transition at the thread and extends 4.5 mm; has an inner radius of 0.8 mm and an outer shoulder radius of 0.5 mm.
FIGS. 6A , 6 B and 6 C respectively represent an axial section view, a cross-section view along Line 6 B— 6 B and a shoulder detail view of a Nipple Connecting Element 502 with flat 506 and having first and second male threaded ends, 501 . a and 501 . b , according to a fifth embodiment of the invention, styled Hollow Rod 42×5 External Upset. In FIG. 6A the values are a Modified SEC thread 505 . b, 8 threads per inch; DEN=50 mm; DIN=17 mm with an expansion to 25.3 mm over a length of 44 mm to the extreme end; DHT=38.6 mm; Beta=83°; overall length=158 mm; thread length=46 mm and central section length=50 mm. The shoulder detail 502 . a in FIG. 6C begins 4.61 mm after the thread, has an inner radius of 1.4 mm and an outer shoulder radius of 0.5 mm.
FIGS. 7A and 7B respectively represent an axial section view and a shoulder detail view of a Hollow Sucker Rod 503 having a first female threaded end 503 . a , according to the fifth embodiment of the invention. In FIG. 7A the values are a Modified SEC thread 505 . a, 8 threads per inch; DEVU ranging from 50 mm to DEV=42 mm; DIFR=41 mm; DIV=36.4 mm with a transition at 15° to 30 mm starting at 55 mm from the free end and back to 32 mm over a maximum length of 150 mm; Beta=83°. The shoulder detail 504 . a in FIG. 7B has a 30° transition at the thread and extends 4.5 mm; has an inner radius of 0.8 mm and an outer shoulder radius of 0.5 mm.
FIGS. 8A , 8 B and 8 C respectively represent an axial section view, a shoulder detail view and a cross-section view along Line 8 B— 8 B of a Nipple Connecting Element 602 with flat 606 and having first and second male threaded ends, 601 . a and 601 . b , according to a sixth embodiment of the invention, styled Hollow Rod 48.8×6 External Upset. In FIG. 8A the values are a Modified SEC thread 605 . b, 8 threads per inch; DEN=60.6 mm; DIN=20 mm with an expansion to 33.6 mm over a length of 44 mm to the extreme end; DHT=47 mm; Beta=83°; overall length=158 mm; thread length=46 mm and central section length=50 mm. The shoulder detail 602 . a in FIG. 8C begins 4.61 mm after the thread, has an inner radius of 1.4 mm and an outer shoulder radius of 0.5 mm.
FIGS. 9A and 9B respectively represent an axial section view and a shoulder detail view of a Hollow Sucker Rod 603 having a first female threaded end 603 . a , according to the sixth embodiment of the invention. In FIG. 9A the values are a Modified SEC thread 605 . a, 8 threads per inch; DEVU ranging from 60.6 mm to DEV=48.8 mm; DIFR=49.4 mm; DIV=44.6 mm with a transition at 15° to 30 mm starting at 55 mm from the free end and back to 35.4 mm over a maximum length of 150 mm; Beta=83°. The shoulder detail 604 . a in FIG. 9B has a 30° transition at the thread and extends 4.5 mm; has an inner radius of 0.8 mm and an outer shoulder radius of 0.5 mm.
FIG. 10A represents an axial section view and dimension detail view of a first female threaded end on a Hollow Sucker Rod showing the configuration of a trapezoidal, non-symmetric thread profile that is a Modified Buttress or SEC thread, according to the rod first end preferred embodiment. The female thread shape of each Hollow Sucker Rod is trapezoidal and non-symmetric and is incomplete. The thread pitch is 8 threads per inch. The thread height is 1.016+0/−0.051 mm. The Diametrical taper in the threaded section is 0.1 mm/mm. The Length of threads on at least the first end of the tubular element is 44 mm., with part of the threads being incomplete due to vanishing of thread on the inside of the tubular element. The thread taper angle is 2° 51′ 45″; the tooth inner surface is 1.46 mm and the teeth spacing is 1.715 mm; the leading edge has a 4° taper or load flank angle and an inner radius of 0.152 mm while the trailing edge has a 8° taper and a larger inner radius of 0.558 mm. At the end of the threaded section a short cylindrical section on the inside of the threaded area transitions the threaded area to the bore of the hollow tubular element.
FIG. 10B represents an axial section view and dimension detail view of a first male threaded end on a Nipple Connecting Element showing the configuration of a trapezoidal, non-symmetric thread profile that is a Modified Buttress or SEC thread, according to the nipple first or second end preferred embodiment. The external diameter of the central section of each Nipple Connecting Element is 50 mm or 60.6 mm and the central section can present a pair of machined diametrically opposite flat surfaces, to be engaged by a wrench during connection make up. The male thread is a Modified Buttress thread and is complete across both ends of the nipple. The threaded section pitch is 8 threads per inch. The thread height lies between 1.016+0.051/−0 mm. The diametrical thread taper in the threaded area is 0.0976 mm/mm. The thread shape is trapezoidal and non-symmetric. The length of threads on each extreme of the nipple is 46 mm. All threads on the nipple are complete. The angle of the conical surface in the torque shoulder (Beta) is 83°. The radius at the tips of the torque shoulder is 1.4 mm for the internal radius and 0.5 mm for the external radius. There are preferred conical bores under each threaded section of the nipple, which are connected by a cylindrical bore. The thread taper angle is 2° 47′ 46″; the tooth inner surface is 1.587 mm and the teeth spacing is 1.588 mm; the trailing edge has a 4° taper or load flank angle and an outer radius of 0.152 mm while the leading edge has a 8° taper and a larger outer radius of 0.558 mm.
FIGS. 11 and 12 illustrate the corrosion problem when a fluid flows through the interior of the rod with reaonable speed. Early wear of the nipple and rod occurs in the area where they connect (overlap). This phenomenon can be attributed to the existence of an “stagnation area” where the fluids remains almost still (low velocity). See Zone A, in FIGS. 11 and 12 .
To solve the above mentioned problem the nipple and rod of the type shown in FIGS. 2A and 2B were modified. FIG. 11 illustrates such a hollow rod 48×6, external flush, with a stagnation area at Zone A and the resulting corrosion illustrated in a photographic section view, by FIG. 12 . A small seal was introduced at the ends of the nipple, with the corresponding modification of the angle of the internal conical bore (Zone B, C and D in FIGS. 13–15 ). With this modification the “stagnation zone” does not exist any more and the fluid flows smoothly and with little turbulence. It is important to note that these modifications are small so that they do not alter significantly the stress distribution in the connection, nor the performance of the product. Note that the illustrated modifications were done on the nipple and the rod ( FIGS. 13–15 ). FIG. 13 represents a slight variation of FIG. 11 . A modification is introduced to the existing Nipple, in terms of a small seal zone, in order to prevent the fluid (when flowing through the inside of the pipe) to remain in the “stagnation area” promoting erosion-corrosion.
The stress distribution on the nipple and rod are similar to the HR 48×6 External Flush illustrated by FIGS. 2A–2C and FIG. 11 .
The torque shoulder ( 701 b , FIGS. 13–14 ) is similar to that in FIG. 11 .
The nominal diameter and diametrical taper in the threaded section ( 702 b , FIGS. 13–14 ) are likewise similar to FIG. 11 .
The nipple threads are complete and the length of threads ( 703 b , FIGS. 13–14 ) is smaller, and different than shown in FIG. 11 . ( 703 a , FIG. 11 ).
There is an external cylindrical zone betwen the end of the nipple and the threaded section ( 704 b , FIGS. 13–14 ). The length is between 10 mm to 27 mm and the external diameter is 36.8 mm. This is different from FIG. 11 .
The end of the nipple works as a seal of the union ( 705 b , FIGS. 13–14 ). The thickness of the end of the nipple is 2 mm, which is different from FIG. 11 . ( 705 a , FIG. 11 ).
The bore of the nipple is conical in the extremes. The preferred angle is 8° 16′ ( 706 b , FIG. 14 ) and is different from FIG. 11 . (3° 46′; See 706 a , FIG. 11 )
The total length of the nipple ( 707 b , FIG. 14 ) is similar to FIG. 11 . ( 707 a , FIG. 11 )
The rod likewise has a torque shoulder ( 708 b , FIGS. 13 and 15 ). The dimensions of that shoulder are similar to the shoulder shown in FIG. 11 . Part of the threads on the pipe or rod end is incomplete due to vanishing of thread on inside of pipe ( 709 b , FIG. 15 ), which is similar to FIG. 11 . The nominal diameter and diametrical taper in the threaded section ( 710 b , FIGS. 13 and 15 ) are similar to FIG. 11 .
There is a seal inside of the rod, near the end of incomplete threads on the rod ( 711 b , FIGS. 13 and 15 ). While that seal may appear to be a second torque shoulder, it does not function as one, and has not been designed to sustain load. The thickness of the seal is between 0 to 1.7 mm and depends on the manufacturing tolerances of the pipe, and is different from the HR 48×6 External Flush version of FIG. 11 . The angle of seal inside of the rod is 90 degrees and the length of it from the end of the pipe is 55 mm ( 711 b and 712 b , FIGS. 13 and 15 ), which is different from FIG. 11 . After “make up” (service torque applied), the separation between the nipple and the rod) at Zone B ranges from about 0 to 0.6 mm ( 713 b , FIG. 13 ). The seal Zone B is lightly loaded and it does not transmit torque. It is used only as a seal and to promote a smooth flowing of the fluid.
FIGS. 16–18 illustrate another embodiment, where the objective is to substantially increase the flow of fluid extracted, through a further modification to the extreme ends of a hollow sucker rod string, of the type illustrated at FIGS. 2A–2C , FIG. 11 or FIG. 13 .
A series of holes were drilled in the rod's body at the two extremes (ground level and well bottom level) of the string. In this way, the fluid is allowed to flow also (usually it does through the annular region between the outer surface of the rod and the inner surface of the “tubing”) through the interior of the Hollow Rod. The holes pattern preferrably may be a Configuration 1 with 2 holes per transverse section, alternating at 90°, with a given longitudinal distance between sections ( FIGS. 16A , 16 B); a Configuration 2 with holes that follow an helicoidal path with a “separation”in the longitudinal direction, and angle between holes of different sections ( FIGS. 17A , 17 B); or a Configuration 3: Three holes per tranverse section with a given longitudinal distance ( FIGS. 18A , 18 B).
FIGS. 16 A,B illustrate one extreme end of hollow rod 803 with 2 holes, 804 , per transverse section, 180° apart, distributed in an alternate way, each set opposed at 90° to the adjacent set of holes with a given distance between sections, p ( FIGS. 16A and 16B ). The preferred hole diameter, Dh, is between 5 mm to 7 mm. The preferred longitudinal distance between sections, p, is between 50 to 100 mm. The preferred total (longitudinal) length of the zone at each extreme end that has such holes, L, is 3000 mm to 4000 mm, with the zone comprising between 62 to 162 holes.
FIGS. 17 A,B illustrate one extreme end of hollow rod 805 with 1 hole, 806 , per transverse section. The holes follow a helicoidal path, with a preferred longitudinal separation or pitch, p ( FIG. 17B ), and a rotation angle from one section to the following of 120°. ( FIGS. 17A and 17B ). The preferred hole diameter, Dh, is between 5 mm and 7 mm. The preferred longitudinal distance between sections, p, is between 25 to 50 mm. The preferred total (longitudinal) length of the zone at each extreme end that has such holes, L, is 3000 mm to 4000 mm, with the zone comprising between 61 to 161 holes.
FIGS. 18 A,B illustrate one extreme end of hollow rod 807 with 3 holes, 808 , per transverse section, each about 120° apart about the circumference, with a preferred longitudinal separation or pitch, p ( FIG. 18B ). The preferred hole diameter, Dh, is between 5 mm and 7 mm. The preferred longitudinal distance between sections, p, is between 50 to 100 mm. The preferred total (longitudinal) length of the zone at each extreme end that has such holes, L, is 3000 mm to 4000 mm, with the zone comprising between 93 to 243 holes.
Therefore, the Modified Nipple (with seal) of FIG. 13 produces smooth fluid flow and little turbulence, when a fluid flows though the inside of the pipe, in turn yielding good erosion-corrosion resistance at Zone B when fluid flows though the inside of the pipe. The nipple of FIG. 14 also is interchangeable with a nipple as in FIG. 11 .
Hence, for all preferred embodiments, there is a diametral or differential taper. For example the rod first end taper is 0.1 inches/inch, while the corresponding taper of the either nipple end is 0.0976 inches/inch. For all preferred embodiments, the angle of the conical surface in the torque shoulder (Beta) is preferably 83°. The radiuses at the tips of the torque shoulder are 0.8 mm for the internal radius and 0.5 mm for the external radius.
Likewise, for all preferred embodiments, the Connecting Element has a central section that is externally cylindrical. Close to the outer diameter of this central section external torque shoulders are located to mate with the torque shoulder on a first end of a Hollow Sucker Rod. Both extremes of a nipple are conical and externally threaded, and a conical inner bore proximate the length of each threaded extreme creates an advantageous combination of structure, to ensure an increasing cross-section of the nipple from each free end of the nipple towards the central section, and the torque shoulder locations.
While preferred embodiments of our invention have been shown and described, the invention is to be solely limited by the scope of the appended claims. | An elongated drive string assembly includes a plurality of hollow sucker rods and connecting elements between a drive head located at the surface of an oil well and a rotary pump located deep down in an oil well, with a series of holes at each end to substantially increase the flow of extracted fluid. Each hollow sucker rod has a first end with a torque shoulder, which engages a torque shoulder formed on a connecting element. The threads are frusto-conical, non-symmetrical threads with a differential diametral taper. The torque shoulders have a maximized mean diameter and cross-sectional area to resist storing reactive torque in the drive string. | 5 |
This application is a continuation of application Ser. No. 07/256,399, filed Oct. 11, 1988, now abandoned.
BACKGROUND OF INVENTION
This invention relates to electronic musical instruments and, more particularly, to a technology for designating how a tone generator synthesizes musical tones.
Electronic musical instruments with a tone generator for synthesizing musical tones using a plurality of waveform generation modules are known in the art. Such waveform generator modules can be connected to one another in various forms, and the entirety of the resultant connected structure specifies the way of synthesizing tones.
An electronic musical instrument disclosed in U.S. Pat. No. 4,554,857 (issued on Nov. 26, 1985) incorporates a set of tone synthesis algorithms each defining a connected structure of a plurality of waveform generator modules. Each tone synthesis algorithm has a uniquely assigned numerical value representing the name of the algorithm. A tone synthesis algorithm is specified by selecting an algorithm number by an input unit. The selected tone synthesis algorithm is executed by a tone generator having a plurality of time-division multiplexed (TDM) modules for the synthesis of a tone.
With this arrangement, the user can select a tone synthesis algorithm but can not program it, i.e., assemble a connected structure of the plurality of tone generator modules. Further, with the increase of the number of tone synthesis algorithms, it becomes difficult for the user to grasp the correspondence between numbers and tone synthesis algorithms.
Further, the tone generator used in the above system is basically of the frequency modulation (FM) type. Therefore, the output of a module is usable in only two alternatives, one for partial output of the tone generator, and the other for part of a phase signal input to the same or a different module.
U.S. patent application Ser. No. 002,121, filed on Jan. 12, 1987, concerning the assignee of this application discloses a tone generator with a plurality of TDM modules, which can utilize the output of each module in various ways, for instance, as part of a synthesized tone, an envelope input to a different module or part thereof or a phase input to a different module or part thereof. Therefore, the number Of tone synthesis algOrithms executable by the tone generator is extremely large and may readily exceed 100,000 for eight modules. The application, however, does not show any technique that permits the user to select or assemble a tone synthesis algorithm.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an electronic musical instrument which allows the user to easily program a configuration of tone synthesis.
Another object of the invention is to provide an electronic musical instrument in which a tone generator can synthesize tones in various ways according to selected tone synthesis algorithms.
A further object of the invention is to provide an electronic musical instrument which permits the user to make the best use of the tone synthesis capacity of a tone generator having a plurality of time-division multiplexed modules.
In accordance with the present invention, there is provided an electronic musical instrument with a tone generator for synthesizing musical tones by using a plurality of time-division multiplexed waveform generator modules, which comprises input means for designating a connection structure of each pair of modules independently of the connection structures of other module pairs such that each module pair forms a tone synthesis unit, and processing means for generating control data for each module in response to the designation by the input means and for transferring the generated control data to the tone generator.
This arrangement has an advantage that the user can readily program a tone synthesis algorithm. Further, in contrast to the prior art, there is no need for the user to confirm the correspondence between numerical values and structures of a plurality of modules.
Preferably, the input means selects each module pair connection structure from:
(a) a mode in which the output of the first or former module in the pair is added to the output of the second or latter module in the pair;
(b) a mode in which the output of the former module is used as a phase signal to the latter module; and
(c) a mode in which the output of the former module is used as part of an envelope signal to the latter module.
There may be further provided display means which visually displays a connected structure of a plurality of modules in response to the designation by the input means.
The electronic musical instrument may further comprise additional input means for independently designating a connection structure of each pair of the tone synthesis units.
With this addition, the number of programmable tone synthesis algorithms is further increased, permitting the user to take full advantage of the tone generator capacity.
Preferably, additional input means selects a connection structure of each pair of tone synthesis units from:
(a) a mode in which the output of the preceding tone synthesis unit in the pair is used as at least part of a phase signal to the latter module in the succeeding tone synthesis unit in the pair; and
(b) a mode in which the output of the preceding tone synthesis unit in the pair is used as at least part of a tone to be output from the tone generator.
Module control data may contain phase distortion control data. In this relation, each module may include means for receiving a phase signal, means for modulating the received phase signal according to the phase distortion control data, sine wave memory means, means for accessing sine wave memory means by using the modulated phase signal, means for receiving an envelope signal and means for multiplying the received envelope signal by an output signal from the sine wave memory means.
The phase signal may be selected according to the module control data from a phase signal from basic parameter generator means, an output signal from the former module, an output signal of the previous tones synthesis unit and the sum of or difference between the output signal of the former module and the output signal from the previous tone synthesis unit. The envelope signal may be selected according to the module control data from an envelope signal from the basic parameter generator means and the sum of the output of the preceding module and the envelope signal from the basic parameter generator means.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the invention will become more apparent from the following detailed description with reference to the accompanying drawings, in which:
FIG. 1 is a block diagram of an electronic musical instrument in accordance with the invention;
FIG. 2 is a block diagram of a tone generator LSI useful instrument;
FIG. 3 shows logical arrangement of a waveform generator for use in the tone generator;
FIG. 4 shows correspondence between operation codes and operations of the waveform generator;
FIG. 5 is a view of an input unit in a first embodiment;
FIG. 6 is a schematic diagram of the waveform generator in the first design, showing respective tone synthesis units;
FIG. 7 is a schematic diagram of the first tone synthesis unit in FIG. 6;
FIG. 8 shows correspondence between operation codes and respective modes of addition, phase and ring modulation of two consecutive modules;
FIG. 9 shows waveform synthesis registers storing instructions of tone synthesis provided by the input unit shown in FIG. 5;
FIG. 10 is a flow chart for generating operation codes for the waveform generator from the contents of the waveform synthesis registers;
FIG. 11 is a view of an input unit in a second embodiment;
FIG. 12 is a schematic diagram of the waveform generator in the second embodiment, showing respective tone synthesis units;
FIG. 13 is a schematic diagram of first two units in FIG. 12;
FIG. 14 shows correspondence between operation codes and the respective positions of the select switches in FIG. 13;
FIG. 15 shows waveform synthesis registers storing instructions of tone synthesis provided by the input unit shown in FIG. 11; and
FIG. 16 is a flow chart for generating operation codes for the waveform generator from the contents of the waveform synthesis registers shown in FIG. 15.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Now, an embodiment of the invention will be described with reference to the drawings. FIG. 1 is a block diagram of an electronic musical instrument incorporating the features of the invention. The states of a keyboard 1 and a switch section 2a, are monitored by CPU 3 to detect key-"on", key-"off", tone color selection, etc. Data concerning the selected tone color, edit, etc. are presented on a display section 2b by CPU 3. For the control of a tone generator LSI 6, the CPU 3 generates the necessary data using a ROM 4 and a RAM 5 and transfers the generated data to the tone generator LSI 6. The tone generator 6 uses an external RAM 7 as an operation buffer to generate tones. The generated tones are converted by a digital-to-analog converter (DAC) into analog signals, which are amplified by an amplifier 9 and sounded by a loudspeaker 10.
FIG. 2 shows a block diagram of the tone generator LSI 6. In this example, the tone generator LSI 6 has an 8-channel structure having 8 modules per channel. An interface/controller 11 provides an interface between CPU 3 and the tone generator LSI 6. It generates timing signals used in various parts of the tone generator LSI 6. Also, it decodes the data transferred from the CPU 3 and writes the decoded data in the external RAM 7 through an external RAM interface 16. An envelope and keycode generator 12 reads and writes data from and in the external RAM 7 via the external RAM interface 16 and generates and supplies envelope and keycode data to an exponential transformation and phase angle generation unit 13. The unit 13 performs exponential transformation of the supplied envelope and keycode data and accumulates the transformed keycode data (differential value of the phase) to generate the phase angle data. In the present example, the envelope and keycode generator 12 samples envelope and keycode data at a relatively low rate because it uses the external RAM 7. On the other hand, the waveform generator 15 samples tones at a high rate. For this reason, the exponential transformation and phase generator unit 13 carries out the rate conversion using an internal buffer (not shown). As a result, the exponential transformation and phase angle generation circuit 13 supplies the phase angle and envelope data to the waveform generator 15 at each channel and module time, maintaining synchronization with the waveform generator 15. An OC register 14 includes a memory for storing data (operation codes) for controlling the operation of the waveform generator 15 for each channel and module. The memory is updated via the interface/controller 11 every time an operation code is transferred from CPU 3. At each channel and module time of the waveform generator 15, the OC register 14 reads out a corresponding operation code from the internal memory and supplies it to the waveform generator 15. The waveform generator 15 selectively uses time-division multiplexed envelope and phase angle data supplied from the exponential transformation and phase angle generation circuit 13 according to time-division multiplexed operation code data for each channel and module provided by the OC register 14 to generate various tones.
FIG. 3 illustrates a logical arrangement of the waveform generator 15. A portion surrounded by the dashed rectangle indicates a waveform generator module 15M which operates on TDM basis. In the Figure, labeled E and ωt are time-division multiplexed envelope data and phase angle data supplied by the exponential transformation and phase angle generation circuit 13 at each channel and module time. The states of selectors XS, ES, TS and SS in the waveform module 15M are each controlled by operation codes provided from the OC register 14 at each channel and module time. The selection circuit XS is for selecting a phase angle used in the waveform module 15M. The phase angle selector XS selects the phase angle according to the operation code from:
(a) phase angle data generated by the exponential transformation and phase angle generation circuit 13;
(b) waveform output W -1 of an immediately preceding module;
(c) output R of temporary register 15-3; or
(d) sum of or difference between (b) and (c).
Designated by ES is an envelope selection circuit which selects;
(a) envelope data E generated by the exponential transformation and phase angle generation circuit 13 when the bit 3 of the operation code OC is "0", and
(b) the past or accumulated waveform R' from the temporary register 15-3 added to the envelope data E when the bit 3 of the operation code OC is "1".
Designated by PD is a phase distortion/noise selection circuit which selects:
(a) no phase distortion when the bits 2 to 0 of the operation code OC is "0",
(b) five progressive phase distortions when the value of the bits 2 to 0 is "1" to "5",
(c) white noise when the value of the bits 2 to 0 is "6", and
(d) the product of white noise and sinusoidal wave, i.e., pink noise, when the value of the bits 2 to 0 is "7".
If no phase distortion is selected the waveform module 15M converts a phase selected by the phase angle selector XS into a sinusoidal wave at that phase using a SINROM 15-1 and multiplies it by an envelope selected by the envelope selector ES using a multiplier 15-2. The output of the multiplier defines the output W of the waveform module 15M.
TS is a circuit for selecting an input to the temporary register 15-3. TS selects the input according to the operation code from:
(a) waveform output W of the current module,
(b) output R of the temporary register, or
(c) sum of or difference between (a) and (b).
SS selects an input to an accumulator 15-4 which accumulates waveforms to form a tone to be supplied to DAC 8.
The input to the accumulator is either:
(a) the result of addition or subtraction of the waveform W of the current module to or from existing accumulated waveform, or
(b) existing accumulated waveform (without change).
Thus, the accumulator input selector SS controls whether to use the waveform output W of the current module as part of a tone to be output from the waveform generator 15.
FIG. 4 shows correspondence between operation codes and operations of the waveform module 15M. A suffix 1 in the Figure indicates an ordinal module number. For example, when the operation code OC is 0X (hexadecimal notation), the input to the accumulator 15-4 is the sum of whatever is in the accumulator Σ and waveform output W i-1 of the preceding module, while the phase angle input X 1 to the current module is given by the phase data ω i t from the exponential transformation and phase angle generation circuit 13.
This invention concerns a technique of designating an operation mode of each TDM waveform module in a tone generator as exemplified by the waveform generator 15. By way of example, two embodiments will be described.
First Embodiment
In a first embodiment or design, a way of combining or interconnecting individual pairs of the modules can be designated using an input unit. There are three ways or modes of combination, i.e., addition mode, phase mode and ring modulation mode. Let E i sin ω i t, be the output waveform of module i. In the addition mode we obtain
E.sub.i sin ω.sub.i t+E(i+1) sin ω(i+1)t.
In the phase mode, the output waveform of the module i constitutes the phase of the next module i+1, so we have
E(i+1) sin (E.sub.i sin ω.sub.i t).
In the ring modulation mode, the output waveform of module i is added to the envelope E(i+1) produced by the exponential transformation and angle generation circuit 13 to define an envelope used in the waveform module i+1. Thus, we obtain
(E(i+1)1+E i sin ω i t) sin ω(i+1)t.
FIG. 5 shows an example of the input unit for designating the above three modes of combination. In the Figure, designated by 2b-1 is a display section. The waveform generator 15 synthesizes a tone using a total of eight modules. If two modules are called a line as a unit (tone synthesis unit), there are a total of four lines. The actual waveform generator 15 noted above can generate tones for eight channels each consisting of eight modules. The following description, however, assumes a single channel for the sake of brevity. Numerals 0 to 3 shown on the left side of the screen of the display 2b-1 represents line numbers. For example, line 0 is a combination of modules 0 and 1. The way of combining each pair of modules is displayed on the right side of the corresponding line number. A line is selected by a cursor key 2a-1, and the way of combination of the pair of modules (addition phase or ring modulation mode) is selected by a value key 2a-2. For example "ADD", in the Figure, means that modules 0 and 1 are added together. The display section 2b-1 is part of the display 2b shown in FIG. 1. The keys 2a-1 and 2a-2 form part of the switch section 2a.
FIG. 6 schematically shows the waveform generator 15 when eight TDM modules of the waveform generator 15 are regarded as four tone synthesis units or lines L 0 to L 3 .
FIG. 7 shows the first tone synthesis line L 0 . The functions of the waveform generator 15 described in conjunction with FIG. 3 are shown here in a simplified form for the sake of explanation of the first design. For example, designated by 15-1 0 is SINROM 15-1 in the module 0, and 15-1 1 is SINROM 15-1 in the module 1. The output of E 0 is an envelope generated by the exponential transformation and phase angle generation circuit 13 (FIG. 2) at a time of module 0, and the output of E 1 is an envelope generated by the circuit 13 at a time of module 1. The other lines L 1 to L 3 are similarly arranged. The relation between the module 0 and 1 can be selected from three modes, i.e., "addition", "phase" and "ring modulation" modes, by means of three select switches SW1 to SW3 shown in the Figure.
FIG. 8 shows correspondence between two operation codes OC0 and OC1 for the respective modules 0 and 1 and the select switches SW1 to SW3 in FIG. 7. OC0 and OC1 on the first row state that the two modules be added. In the case of OC0 and OC1 on the second row, the output of the preceding module (module 0) becomes the phase of the succeeding module (module 1). OC0 and OC1 on the third row indicates the ring modulation.
FIG. 9 shows waveform synthesis registers MD01, MD23, MD45 and MD67 set by the input unit shown in FIG. 5. These registers are provided in the RAM 5 shown in FIG. 1. The lowest two bits of each register specifies the relation between two modules. The CPU 3 in FIG. 1 generates each operation code from the contents of each register and transfers it to the OC register 14 of the tone generator LSI 6.
FIG. 10 shows a flow chart of generating operation codes OC as done by CPU 3. The CPU 3 checks the lowest two bits of each of the registers MD01, MD23, MD45 and MD67 in the steps S0, S4, S8 and S12. If the lowest two bits are "00" representing an addition, the CPU makes the operation code for the preceding module equal to "00" and the operation code for the succeeding module equal to "00" (steps S1, S5, S9 and S13). As is seen from FIGS. 4 and 8, with this combination of operation codes, the waveform generator 15 executes addition of two modules. When the lowest two bits are "01" representing a phase operation, the operation codes of the preceding and succeeding modules are respectively "00" and "A0" (steps S2, S6, S10 and S14). As a result, the waveform generator 15 selects the output of the preceding module as the phase input to the succeeding module. When the lowest two bits are "1X" (where X is a "don' t care" bit) representing a ring modulation operation the operation codes of the preceding and succeeding modules are respectively "00" and "88" (S3, S7, S11 and S15). As a result, the envelope used in the succeeding module i+1 is given by
(E.sub.(i+1) +E.sub.i)sin ω.sub.i t
and the ring modulation is achieved.
Since there are three different ways of combining two modules, a total of eight modules reside in the tone generator, and each tone synthesis line is independent of the others, there are a total of 3 4 i.e., eighty one possible tone synthesis combinations.
In this manner, the first embodiment regards the eight TDM waveform modules provided in the waveform generator 15 as four different pairs of modules, and allows the connection structure of each module pair (line) to be selected using the input unit.
Second Embodiment
A second embodiment or design allows, in addition to the requirements of the first design, the waveform output of the current line to be used as either
(a) a phase input to the latter module of the next line or part of the input, or
(b) a tone.
By adding the selection (a), the module phase input may contain a plurality of frequency components, thus enriching tones generated.
FIG. 11 shows an input unit for use in the second design. As is seen from the screen of a display section 2b-1, it is possible to select both the relation of two modules constituting a line (i.e., either addition, phase or ring modulation) and the relation of the current line with the next. "ON" shows that the current line output is supplied to the input of the next line. "OFF" shows that the line output is not supplied as the input to the next line but is used as a tone. A cursor key 2a-1 selects a line number, or a value key 2b-1 selects the line-setting data.
FIG. 12 schematically shows the waveform generator 15 in the second design. The second design is the same as the first insofar as two consecutive modules are regarded as a single tone synthesis line but is different in that each line output can be input to the next line.
FIG. 13 shows an arrangement of the first and second tone synthesis line L 0 and L 1 in FIG. 12.
Select switches SW1 to SW 3 in the unit L 0 and select switches SW5 to SW7 in the unit L 1 serve to select module relation in each line from the addition, phase and ring modulation modes. Select switches SW4 and SW8, which are additionally provided in the second design, determine whether the line output is supplied to the next line or used as a tone.
In FIG. 13, if the select switch SW4 has its pole thrown to the left, the output α 0 of the line L 0 is supplied to the next line L 1 . The line L 1 provides
E.sub.3 sin (α.sub.0)+E.sub.2 sin ω.sub.2 t,
E.sub.3 sin (α.sub.0 +E.sub.2 sin ω.sub.2 t), and
(E.sub.3 +E.sub.2 sin ω.sub.2 t) sin (α.sub.0)
when the switches SW5, SW6 and SW7 are in the center, lower and left positions, in the upper, lower and right positions and in the center, upper and right positions, respectively. Generally, when the output α i/2-1 of the line i/2-1 is supplied to the next line 1/2, the output of the latter is either
E(i+1) sin (α.sub.i/2-1)+E.sub.i sin ω.sub.i t,
E(i+1) sin (α.sub.i/2-1 +E.sub.i sin ω.sub.i t), or
(E(i+1)+E.sub.i sin ω.sub.i t) sin (α.sub.i/2-1).
FIG. 14 shows correspondence between operation codes and positions of select switches SW1 to SW8. For example, when OC0="00", OC1="80", OC2="40" and OC3="10" as seen in the first row, the output of the first line L 0 is
E.sub.0 sin ω.sub.0 t+E.sub.1 sin ω.sub.1 t.
This output constitutes the phase input to the second line L 1 . The module 3 of L 1 provides
E.sub.3 sin (E.sub.0 sin ω.sub.0 t+E.sub.1 sin ω.sub.1 t).
This output is added to the output E 2 sin ω 2 t of the module 2 of the line L 1 . More specifically, this is read from FIGS. 3 and 4. With OC="00" a waveform E 0 sin ω 0 t is generated by the module 0. This is supplied to the temporary register 15-3 in FIG. 3 (R=E 0 sin ω 0 t) with OC1 ="80". Further, with OC1="80" a waveform E 1 sin ω 1 t is generated by the module 1, and with OC2="40" this waveform is added to the previous E 0 sin ω 0 t, the sum being supplied to the temporary register 15-3 (R=E 0 sin ω 0 t+E 1 sin ω 1 t). Further, with OC2="40" a waveform E 2 sin ω 2 t is generated by the module 2, and with OC3="10" the content E 0 sin ω 0 t+E 1 sin ω 1 t of the temporary resister 15-3 is supplied as phase input to the module 3. The module 3 provides an output E 3 sin (E 0 sin ω 0 t+E 1 sin ω 1 t), and with OC3="10" the waveform E 2 sin ω 2 t from the module 2 is supplied to the accumulator 15-4 (Σ=E 2 sin ω 2 t). Although not shown in FIG. 14, the operation code OC4 of the next module is "00" (see FIG. 16 to be described later). Thus, the output of the module 3 is added to the waveform of the preceding module 2 and supplied to the accumulator 15-4 (Σ=E 2 sin ω 2 t+E 3 sin (E 0 sin ω 0 t+E 1 sin ω 1 t).
FIG. 15 shows waveform synthesis registers MD01, MD23, MD45 and MD67 which are altered by the input unit shown in FIG. 11. As in the first design, each lowest two bits designate the relation of two modules forming a line. Each bit 2 serves to determine whether the line output is to be provided as phase input to the next line or a tone. The CPU 3 generates operation codes for respective modules from these waveform synthesis registers MD01, MD23, MD45 and MD67 and transfers these codes to the OC register 14 of the tone generator.
FIG. 16 is a flow chart of generating operation codes as is done by the CPU 3. This will now be described in conjunction with some examples of tone synthesis.
The synthesis of E 2 sin ω 2 t+E 3 sin (E 0 sin ω 0 t+E 1 sin ω 1 t) has been described. In this case, MD01="04", and MD23="00". In the routine, OC0="00", OC1="80", OC2="40", OC3="10" and OC4="00" are generated through steps T1, T2, T3, T6, T33 and T34.
Now, synthesis of E 3 sin (E 2 sin ω 2 t+E 1 sin ω 1 t+E 0 sin ω 0 t) will be considered. In this case, MD01="40", and MD23="01". According to the routine, OC0="00", OC1 ="80", OC2="40", OC3="70" and OC4="00" are generated (steps T1, T2, T3, T6, T33 and T35). The synthesis operation is the same as the first example up to OC2. In the next OC3, the phase input X 3 receives
W.sub.2 +R=E.sub.2 sin ω.sub.2 t+E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t.
Thus, the output W 3 of the module 3 is given by
E.sub.3 sin (E.sub.2 sin ω.sub.2 t+E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t).
This is supplied to the accumulator with the next operation code OC4="00" stating
Σ=Σ+W.sub.3.
Now, the synthesis of (E 3 +E 2 sin ω 2 t) sin (E 1 sin ω 1 t +E 0 sin ω 0 t) will be considered. In this case, MD01="04", and MD23="02". The routine generates OC0="00", OC1="80", OC2="40", OC3="98" and OC4="00" (steps T1, T2, T3, T6, T33 and T36). This example is the same as the preceding examples up to OC2. With OC3="98", the output R (=E 1 sin ω 1 t+E 0 sin ω 0 t) of the temporary register 15-3 is selected as the phase input X 3 to the module 3, and E 3 +R' (R'=W 2 =E 2 sin ω 2 t) is selected as the envelope input. The module 3 provides (E 3 +E 2 sin ω 2 t) sin (E 1 sin ω 1 t+E 0 sin ω 0 t) which is then supplied to the accumulator 15-4 with OC4.
Now, when providing E 3 sin (E 2 sin ω 2 t+E 1 sin (E 0 sin ω 0 t)), MD01="05" and MD23="01". Thus, the routine generates OC0="00", OC1="A0", OC2="80", OC3="70" and OC4="00" (steps T1, T2, T4, T6, T33 and T35). Up to OC2 this example is the same as the preceding examples. With OC3
X.sub.3 ←R+W.sub.2
is executed, and with OC4
Σ←Σ+W.sub.3
is executed, to obtain
W.sub.3 =E.sub.3 sin (W.sub.2 +R)=E.sub.3 sin (E.sub.2 sin ω.sub.2 t+E.sub.1 sin (E.sub.0 sin ω.sub.0 t))
When providing (E 3 +E 2 sin ω 2 t) sin (E 1 sin (E 0 sin ω 0 t)), MD01="05" and MD23="02". Thus, OC0="00", OC1 ="A0", OC2="80", OC3="98" and OC4="00" are generated in the routine (steps T1, T2, T4, T6, T33 and T36). This example is the same as the preceding examples up to OC2. With OC3
X.sub.3 ←R(=E.sub.1 sin (E.sub.0 sin ω.sub.0 t)).
Then,
R'←W.sub.2 (=E.sub.2 sin ω.sub.2 t)
and then
W.sub.3 ←(E.sub.3 +R') sin X.sub.3
are executed. With OC4
Σ←Σ+W.sub.3
is executed. Here we have
W.sub.3 =(E.sub.3 +E.sub.2 sin ω.sub.2 t) sin (E.sub.1 sin (E.sub.0 sin ω.sub.0 t)).
In any of the first three examples, the line L 0 performs addition, and in the latter two examples the line L 0 uses the module 0 output as the phase to the module 1. When the line L0 is in the ring modulation mode, MD01="06", and OC0="00", OC1="88" and OC2="80" (step T4). With OC0
X.sub.0 ←ω.sub.0 t
is executive, and with OC1
X.sub.1 ←ω.sub.1 t,
R←W.sub.0 (E.sub.0 sin X.sub.0 =E.sub.0 sin ω.sub.0 t) and
W.sub.1 ←(E.sub.1 +R) sin X.sub.1
are executed. Thus, we have
W.sub.1 =(E.sub.1 +E.sub.0 sin ω.sub.0 t) sin ω.sub.1 t.
This is then stored in R with OC2. Thereafter, the line L 1 is designated in the same way as in the above examples. Thus, R i, e., contents of the temporary register 15-3 are used in one of the following:
E.sub.3 sin R+E.sub.2 sin ω.sub.2 t,
E.sub.3 sin (R+E.sub.2 sin ω.sub.2 t) or
(E.sub.3 +E.sub.2 sin ω.sub.2 t) sin R.
For example, when synthesizing E 7 sin (E 5 sin (E 3 sin (E 1 sin ω 1 +E 0 sin ω 0 t)+E 2 sin ω 2 t)+E 4 sin ω 4 t)+E 6 sin ω 6 t, MD01="04", MD23="04", MD45="04" and MD67="00". In the routine, OC0="00", OC1="80", OC2="40", OC3="90", OC4="40", OC5="90", OC6="40" and OC7="10" are generated as the operation codes (step T1, T2, T3, T6, T7, T8, T11, T12, T13, T16 and T17). Using suffix as module numbers of waveform generator 15M, respective functions of OC0 to
OC0: Σ←W.sub.7 +Σ, X.sub.0 ←ω.sub.0 t
OC1: R.sub.1 ←W.sub.0, X.sub.1 ←ω.sub.1 t
OC2: R.sub.2 ←W.sub.1 +R.sub.1, X.sub.2 ←ω.sub.2 t
OC3: R.sub.3 ←W.sub.2, X.sub.3 ←R.sub.2
OC4: R.sub.4 ←W.sub.3 +R.sub.3, X.sub.4 ←ω.sub.4 t
OC5: R.sub.5 ←W.sub.4, X.sub.5 ←R.sub.4
OC6: R.sub.6 ←W.sub.5 +R.sub.5, X.sub.6 ←ω.sub.6 t
OC7: Σ←W.sub.6, X.sub.7 ←R.sub.6
The final contents Σ of the accumulator 15-4 are Σ=W 7 +W 6 =E 7 sin X 7 +E 6 sin X 6 =E 7 sin R 6 +E 6 sin ω 6 t. Here,
R.sub.6 =W.sub.5 +R.sub.5 =E.sub.5 sin X.sub.5 +W.sub.4 =E.sub.5 sin R.sub.4 +E.sub.4 sin ω.sub.4 t,
where
R.sub.4 =W.sub.3 +R.sub.3 =E.sub.3 sin X.sub.3 +W.sub.2 =E.sub.3 sin R.sub.2 +E.sub.2 sin ω.sub.2 t,
where
R.sub.2 =W.sub.1 +R.sub.1 =E.sub.1 sin X.sub.1 +W.sub.0 =E.sub.1 sin ω.sub.1 t +E.sub.0 sin X.sub.0 =E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t.
Therefore, the final output is
E.sub.7 sin (E.sub.5 sin (E.sub.3 sin (E.sub.1 sin ω.sub.1 t+E.sub.0 sin ω.sub.0 t) +E.sub.2 sin ω.sub.2 t)+E.sub.4 sin ω.sub.4 t)+E.sub.6 sin ω.sub.6 t.
As has been shown, in the second design either the addition, phase or ring modulation mode can be selected for each module pair or line. It is also possible to make a selection as to whether the result of each line is used as the phase or partial phase input to the latter module of the next line or provided as a tone. The waveform generator 15 operates a total of eight TDM modules, so that 3 4 *2 3 =648 different tone synthesis combinations are possible.
While preferred embodiments of the invention have been described, various changes and modifications are obvious to a person having an ordinary skill in the art without departing from the scope of invention. For example, the display unit may provide a graphic representation of the connection structure of a plurality of modules. Thus, the scope of the invention should be defined solely by the appended claims. | An electronic material instrument includes a tone generator for synthesizing tones by using a number of time-division multiplexed (TDM) modules, an input unit for programming a connection configuration (tone synthesis algorithm) for the modules of each module pair, and a processing unit for converting the input program into control data for each module and transferring the control data to the tone generator. In one embodiment, each module pair is selectively operative in an addition mode, a phase mode or a ring modulation mode, independently of the modes selected for the other module pairs. It is thus possible to attain a tone synthesis desired by the user, and to make the best use of the capacity of the tone generator. | 8 |
BACKGROUND OF THE INVENTION
1. Technical Field:
This device relates to the mounting of glass panes or the like in mounting frames in doors known as door lights in entry doors.
2. Description of Prior Art:
Prior Art devices of this type have used a variety of common construction practices including the traditional use of wood moldings and glazing or the more recent practice of molded plastic frames. The plastic frames secured to one another by screws clamping the frames onto the exterior edge surface of an opening in a door with the window pane held between the frames. The plastic frames have most recently been used on modern metal doors typically having a thin metal skin filled with expanded resin foam for strength and insulation value, see for example U.S. Pat. Nos. 4,259,818, 3,760,543, and 3,903,669.
In U.S. Pat. No. 4,259,818 a tamper proof window unit is disclosed that secures a window frame in a door. The frame members extend outwardly over and down the adjacent exterior surfaces of the door to discourage removal of the frame and the window glass positioned therein.
U.S. Pat. No. 3,903,669 discloses a mounting assembly for snap together complimentary molding members. Each molding member has projecting studs that receive a connector member that secure the molding members together on the outside peripheral edge of the opening.
In U.S. Pat. No. 3,760,543 a door light unit is disclosed having a pair of oppositely disposed identical mounting frame members that are joined together on a window pane and the outer peripheral edge of the door adjacent the door light opening by a clamping action between registering pins.
SUMMARY OF THE INVENTION
A window mounting assembly for the flush mounting of door lights or the like within a door. The mounting assembly uses oppositely disposed identical extruded members to secure a window pane therebetween and to a registering extrusion secured within an opening in the door. Both the extrusions use dual durometer surfaces of yieldable material to form assembly gasket surfaces between the window pane, the door and each other. The registering extrusion is positioned in the door during fabrication.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a portion of a door light unit in a door;
FIG. 2 is a cross-sectional view of a mounting extrusion;
FIG. 3 is a cross-section of a glass mounting extrusion;
FIG. 4 is an exploded perspective view showing the assembly of the mounting extrusion within the door at point of fabrication;
FIG. 5 is an external view of a door with an assembled door light within; and
FIG. 6 is an end view on lines 6--6 of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIGS. 5 and 6 of the drawings a door 10 can be seen having a door light assembly 11 positioned flush within. The door light assembly 11 comprises a window pane 12 held within a two-part molding mounting frame 13. Referring now to FIGS. 1-4 of the drawings the molding mounting frame 13 is comprised of a pair of oppositely disposed identical plastic resin extrusion members 14 which when secured together by a fastener form a continuous glass engagement channel 15 for the mounting of the window pane 12 therebetween. Each of the extrusion members 14 best seen in FIG. 3 of the drawings has an inner surface 16 and an outer contoured surface 17. An alignment and fixation rib 18 extends from the inner surface 16 and has a longitudinally extending V-shaped groove 19 within. A caulking groove 20 is formed within a vertically ascending surface 21 of the inner surface 16 defining with the rib 18 a portion of the glass engagement channel 15 as hereinbefore described. A portion of the vertically ascending surface 21 above the caulking groove 20 is formed on its surface by a dual durometer of a softened more resilient plastic resin material at 22 which extends above the body of the extrusion to define a sealing flange 23.
The outer surface 17 of the extrusion 14 is angularly disposed from the flange 23 to a point opposite said rib 16. The portion of the inner surface 16 extending below said alignment and fixation rib 18 defines in combination with the rib 18 a mounting channel 24 when the pair of extrusion members 14 are in abutting relationship to receive the window pane 12 as seen in FIG. 1 of the drawings. The mounting channel 24 is registrable on an inner bar extrusion 25 that can best be seen in FIG. 2 of the drawings comprising a horizontally disposed base portion 26 having oppositely disposed down-turned flanges 27 and a upstanding hollow body 28 positioned therebetween. A pair of oppositely disposed elongated arcuate flexible flanges 29 are formed by the dual durometer process of resilient resin and extend respectively from an integral extension of a resilient resin portion 30 on the outer facing surface of the down-turned flanges 27. The vertical extending surfaces of the upstanding hollow body 28 also have the resilient resin portion 30 thereon.
Referring now to FIG. 4 of the drawings the inner bar extrusion 25 can be seen for inclusion into the metal door 10 having a door light opening 31 therein and having inturned door flanges 32. Once assembled the door flanges 32 engage and compress the flexible flanges 29 on the inner bar extrusion 25 which in combination with the resilient outer facing surface portion 30 form an effective seal between the inner bar extrusion 25 and the door 10 around its door light opening 31.
During assembly the extrusion members 14 are positioned around one side of the glass pane 12 and inserted-into the door light opening 31 and abutting both the inner bar extrusion 25 and the inturned flange 32 of the door 10 whereby engaging the exposed portion of the elongated resilient flange 29 deflecting same.
Once positioned co-facing additional extrusion members 14 are inserted around the opposite side of the glass pane 12 engaging the insert bar extrusion 25 and the earlier positioned extrusion member 14. A plurality of screw type fasteners 33 are positioned in longitudinally spaced relation to each other through the adjoining extrusion members 14 from one side using the V-shaped grooves 19 for center alignment of the respective joined extrusion members 14.
As assembled the door light assembly 11 is securely held and aligned within the door light opening 31 by the multiple sided engagement on the inner bar extrusion 25 flush within the door light opening 31. Since the extrusion members 14 are flush within the door light opening 31 shipping and handling damage to same is greatly reduced, thus reducing overall production costs and increased production and delivery efficiency.
It will be apparent in the above described assembly that the screw fasteners 33 are inserted through pilot holes drilled through one of the abutting extrusions 14 and said screw fasteners 33 will engage and center on the other extrusion 14 by the alignment guide groove 19 hereinbefore described.
Caulking compound 34 is disposed within the groove 20 prior to assembly to assure a weather tight seal between the glass pane 12 and the extrusion 14. The sealing flange 23 also effects sealing relationship with the glass pane 12 by its flexible configuration that is integral with the outer surface 17 as hereinbefore described.
It should be noted that the glass pane 12 is typically of an insulating type dual pane configuration utilizing a air space between the glass panes and a sealing spacer 35 around the perimeter edge of the window pane 12 to form an insulated glass unit well known and understood in the art. | A window mounting assembly for the flush mounting of door lights or the like. The mounting assembly utilizes a pair of reversible female extrusions joined to a male extrusion secured within the mounting article. The male and female extrusions have dual durometer surfaces and flanges as sealing means between each other, the door, and the door light. | 4 |
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] Embodiments disclosed herein relate generally to a thermoplastic foam shock absorbing layer. In another aspect, embodiments described herein relate to a synthetic turf including a thermoplastic foam shock absorbing layer, where the foam may be recyclable.
[0003] 2. Background
[0004] Artificial turf consists of a multitude of artificial grass tufts extending upward from a sheet substrate. The turf is usually laid upon a prepared, flat ground surface to form a game playing field intended to simulate a natural grass playing field surface.
[0005] For some types of games, a resilient underpad is placed beneath the turf and upon the firm ground support surface to provide a shock absorbing effect. Also, in some instances, a layer of sand or other particulate material is placed upon the upper surface of the carpet base sheet and around the strands. An example of this type of construction is shown in U.S. Pat. No. 4,389,435 issued Jun. 21, 1983 to Frederick T. Haas, Jr. Another example is shown in U.S. Pat. No. 4,637,942 issued Jan. 20, 1987 to Seymour A. Tomarin.
[0006] Further, examples of artificial turfs which are formed with the grass-like carpet placed upon a resilient underpad are disclosed in U.S. Pat. No. 3,551,263 issued Dec. 29, 1970 to Carter et al., which discloses a polyurethane foam underpad; U.S. Pat. No. 3,332,828 issued Jul. 25, 1967 to Faria et al., which discloses a PVC foam plastic or polyurethane foam plastic underpad; U.S. Pat. No. 4,637,942 issued Jan. 20, 1987 to Seymour A. Tomarin which discloses a rubber-like underpad; U.S. Pat. No. 4,882,208 issued Nov. 21, 1989 to Hans-Urich Brietschidel, which illustrates a closed cell crosslinked polyethylene foam underpad; U.S. Pat. No. 3,597,297 issued Aug. 3, 1971 to Theodore Buchholz et al., which discloses a polyurethane underpad having voids; and U.S. Pat. No. 4,505,960 issued Mar. 19, 1985 to James W. Leffingwell, which discloses shock absorbing pads made from elastomer foams of polyvinyl chloride, polyethylene, polyurethane, polypropylene, etc.
[0007] Shock absorbing layers may, of course, be more broadly used in other applications, such as in energy dampening in floors, for example. What is still needed, therefore, are improved materials and methods for forming shock absorbing layers, including recyclable shock absorbing layers.
SUMMARY OF INVENTION
[0008] In one aspect, embodiments disclosed herein relate to a synthetic turf surface comprising a synthetic grass carpet having a flexible base sheet, and a shock absorbing pad, wherein the shock absorbing pad comprises a non-crosslinked polyolefin foam.
[0009] Other aspects and advantages of the invention will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF FIGURES
[0010] FIG. 1 illustrates instrumentation and experimentation for a shock absorption test using FIFA standards.
[0011] FIGS. 2 and 2 c compare results of the compressive stress-strain behavior analyses of foams according to embodiments disclosed herein to those of crosslinked polyethylene foams.
[0012] FIGS. 3 and 3 c compare compressive strain versus time test results for foams according to embodiments disclosed herein to those of crosslinked polyethylene foams.
[0013] FIG. 4 compare compressive creep behavior test results for foams according to embodiments disclosed herein to those of crosslinked polyethylene foams.
[0014] FIG. 5 illustrates synthetic turf that may be formed using embodiments of the non-crosslinked polyolefin foams described herein.
DETAILED DESCRIPTION
[0015] General Definitions and Measurement Methods:
[0016] The following terms shall have the given meaning for the purposes of this invention:
[0017] “Polymer” means a substance composed of molecules with large molecular mass consisting of repeating structural units, or monomers, connected by covalent chemical bonds. The term ‘polymer’ generally includes, but is not limited to, homopolymers, copolymers such as block, graft, random and alternating copolymers, terpolymers, etc., and blends and modifications thereof. Further, unless otherwise specifically limited, the term ‘polymer’ shall include all possible geometrical configurations of the molecular structure. These configurations include isotactic, syndiotactic, random configurations, and the like.
[0018] “Interpolymer” means a polymer prepared by the polymerization of at least two different types of monomers. The generic term “interpolymer” includes the term “copolymer” (which is usually employed to refer to a polymer prepared from two different monomers) as well as the term “terpolymer” (which is usually employed to refer to a polymer prepared from three different types of monomers). The class of materials known as “interpolymers” also encompasses polymers made by polymerizing four or more types of monomers.
[0019] Density of resins and compositions is measured according to ASTM D792.
[0020] Density of foams is measured according to ASTM D3575/W/B.
[0021] “Melt Index (I2)” is determined according to ASTM D1238 using a weight of 2.16 kg at 190° C. for polymers comprising ethylene as the major component in the polymer. “Melt Flow Rate (MFR)” is determined according to ASTM D1238 using a weight of 2.16 kg at 230° C. for polymers comprising propylene as the major component in the polymer.
[0022] Molecular weight distribution of the polymers is determined using gel permeation chromatography (GPC) on a Polymer Laboratories PL-GPC-220 high temperature chromatographic unit equipped with four linear mixed bed columns (Polymer Laboratories (20-micron particle size)). The oven temperature is at 160° C. with the autosampler hot zone at 160° C. and the warm zone at 145° C. The solvent is 1,2,4-trichlorobenzene containing 200 ppm 2,6-di-t-butyl-4-methylphenol. The flow rate is 1.0 milliliter/minute and the injection size is 100 microliters. About 0.2% by weight solutions of the samples are prepared for injection by dissolving the sample in nitrogen purged 1,2,4-trichlorobenzene containing 200 ppm 2,6-di-t-butyl-4-methylphenol for 2.5 hrs at 160° C. with gentle mixing.
[0023] The molecular weight determination is deduced by using ten narrow molecular weight distribution polystyrene standards (from Polymer Laboratories, EasiCal PS1 ranging from 580-7,500,000 g/mole) in conjunction with their elution volumes. The equivalent polypropylene molecular weights are determined by using appropriate Mark-Houwink coefficients for polypropylene (as described by Th. G. Scholte, N. L. J. Meijerink, H. M. Schoffeleers, and A.M.G. Brands, J. Appl. Polym. Sci., 29, 3763-3782 (1984)) and polystyrene (as described by E. P. Otocka, R. J. Roe, N. Y. Hellman, P. M. Muglia, Macromolecules, 4, 507 (1971)) in the Mark-Houwink equation:
[0000] {N}=KM a where K pp =1.90E-04, a pp =0.725 and K ps =1.26E-04, a ps =0.702.
[0000] “Molecular weight distribution” or MWD is measured by conventional GPC per the procedure described by Williams, T.; Ward, I. M. Journal of Polymer Science, Polymer Letters Edition (1968), 6(9), 621-624. Coefficient B is 1. Coefficient A is 0.4316.
[0024] The term high pressure low density type resin is defined to mean that the polymer is partly or entirely homopolymerized or copolymerized in autoclave or tubular reactors at pressures above 14,500 psi (100 MPa) with the use of free-radical initiators, such as peroxides (see for example U.S. Pat. No. 4,599,392, herein incorporated by reference) and includes “LDPE” which may also be referred to as “high pressure ethylene polymer” or “highly branched polyethylene”. The cumulative detector fraction (CDF) of these materials is greater than about 0.02 for molecular weight greater than 1000000 g/mol as measured using light scattering. CDF may be determined as described in WO2005/023912 A2, which is herein incorporated by reference for its teachings regarding CDF. The preferred high pressure low density polyethylene material (LDPE) has a melt index MI (I2) of less than about 20, more preferably less than about 15, most preferably less than 10, and greater than about 0.1, more preferably greater than about 0.2, most preferably more than 0.3 g/10 min. The preferred LDPE will have a density between about 0.915 g/cm3 and 0.930 g/cm 3 , with less than 0.925 g/cm 3 being more preferred.
[0025] “Crystallinity” means atomic dimension or structural order of a polymer composition. Crystallinity is often represented by a fraction or percentage of the volume of the material that is crystalline or as a measure of how likely atoms or molecules are to be arranged in a regular pattern, namely into a crystal. Crystallinity of polymers can be adjusted fairly precisely and over a very wide range by heat treatment. A “crystalline” “semi-crystalline” polymer possesses a first order transition or crystalline melting point (Tm) as determined by differential scanning calorimetry (DSC) or equivalent technique. The term may be used interchangeably with the term “semicrystalline”. The term “amorphous” refers to a polymer lacking a crystalline melting point as determined by differential scanning calorimetry (DSC) or equivalent technique.
[0026] Differential Scanning Calorimetry (DSC) is a common technique that can be used to examine the melting and crystallization of semi-crystalline polymers. General principles of DSC measurements and applications of DSC to studying semi-crystalline polymers are described in standard texts (e.g., E. A. Turi, ed., Thermal Characterization of Polymeric Materials, Academic Press, 1981). DSC is a method suitable for determining the melting characteristics of a polymer.
[0027] DSC analysis was done using a model Q1000 DSC from TA Instruments, Inc. DSC is calibrated by the following method. First, a baseline is obtained by running the DSC from −90° C. to 290° C. without any sample in the aluminum DSC pan. Then 7 milligrams of a fresh indium sample is analyzed by heating the sample to 180° C., cooling the sample to 140° C. at a cooling rate of 10° C./min followed by keeping the sample isothermally at 140° C. for 1 minute, followed by heating the sample from 140° C. to 180° C. at a heating rate of 10° C./min. The heat of fusion and the onset of melting of the indium sample are determined and checked to be within 0.5° C. to 156.6° C. for the onset of melting and within 0.5 J/g to 28.71 J/g for the heat of fusion. Then deionized water is analyzed by cooling a small drop of flesh sample in the DSC pan from 25° C. to −30° C. at a cooling rate of 10° C./min. The sample is kept isothermally at −30° C. for 2 minutes and heated to 30° C. at a heating rate of 10° C./min. The onset of melting is determined and checked to be within 0.5° C. to 0° C.
[0028] Polymer samples were pressed into a thin film at an initial temperature of 190° C. (designated as the ‘initial temperature’). About 5 to 8 mg of sample is weighed out and placed in the DSC pan. The lid is crimped on the pan to ensure a closed atmosphere. The DSC pan is placed in the DSC cell and then heated at a rate of about 100° C./min to a temperature (T o ) of about 60° C. above the melt temperature of the sample. The sample is kept at this temperature for about 3 minutes. Then the sample is cooled at a rate of 10° C./min to −40° C., and kept isothermally at that temperature for 3 minutes. Consequently the sample is heated at a rate of 10° C./min until complete melting. Enthalpy curves resulting from this experiment are analyzed for peak melt temperature, onset and peak crystallization temperatures, heat of fusion and heat of crystallization, and any other DSC analyses of interest.
[0029] For a polymer comprising polypropylene crystallinity is analyzed, T o is 230° C. T o is 190° C. when polyethylene crystallinity is present and no polypropylene crystallinity is present in the sample.
[0030] Percent crystallinity by weight is calculated according to the following formula:
[0000]
Crystallinity
(
wt
.
%
)
=
Δ
H
Δ
H
o
×
100
%
[0000] such that the heat of fusion (ΔH) is divided by the heat of fusion for the perfect polymer crystal (ΔH o ) and then multiplied by 100%. For ethylene crystallinity, ΔH o is taken to be 290 J/g. For example, an ethylene-octene copolymer which upon melting of its polyethylene crystallinity is measured to have a heat of fusion of 29 J/g; the corresponding crystallinity is 10% by weight. For propylene crystallinity, ΔH o is taken to be 165 J/g. For example, a propylene-ethylene copolymer which upon melting of its propylene crystallinity is measured to have a heat of fusion of 20 J/g; the corresponding crystallinity is 12.1% by weight.
[0031] “Non crosslinked” As used herein, the term non-crosslinked refers to polymers that have between 0-10% gel, more preferably, 0-5%, and more preferably 0-1%. It should not be construed that absolutely zero crosslinking is present, as some crosslinking may inevitably occur during processing, but that the crosslinking should be kept to a minimum to allow for recyclability.
Foam Shock Absorbing Layer
[0032] In one aspect, embodiments described herein relate to a thermoplastic foam shock absorbing layer. In another aspect, embodiments described herein relate to a synthetic turf including a thermoplastic foam shock absorbing layer. In selected applications, embodiments described herein relate to a thermoplastic non-crosslinked polymer foam shock absorption layer having the following characteristics:
[0033] 1) Foam thickness: between 8 and 30 mm;
[0034] 2) Foam density: between 30 and 150 kg/m3;
[0035] 3) Foam cell size: between 0.2 and 3 mm; and
[0036] 4) % Open cell volume is low, so as to avoid water uptake: typically less than 35%.
[0037] Polymer
[0038] The thermoplastic polymer used to form the shock absorbing layer may vary depending upon the particular application and the desired result. In one embodiment, for instance, the polymer is an olefin polymer. As used herein, an olefin polymer, in general, refers to a class of polymers fanned from hydrocarbon monomers having the general formula C n H 2n . The olefin polymer may be present as a copolymer, such as an interpolymer, a block copolymer, or a multi-block interpolymer or copolymer.
[0039] In one particular embodiment, for instance, the olefin polymer may comprise an alpha-olefin interpolymer of ethylene with at least one comonomer selected from the group consisting of a C 3 -C 20 linear, branched or cyclic diene, or an ethylene vinyl compound, such as vinyl acetate, and a compound represented by the formula H 2 C═CHR wherein R is a C 1 -C 20 linear, branched or cyclic alkyl group or a C 6 -C 20 aryl group. Examples of comonomers include propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-octene, 1-decene, and 1-dodecene.
[0040] In other embodiments, the polymer may be an alpha-olefin interpolymer of propylene with at least one comonomer selected from the group consisting of ethylene, a C 4 -C 20 linear, branched or cyclic diene, and a compound represented by the formula H 2 C═CHR wherein R is a C 1 -C 20 linear, branched or cyclic alkyl group or a C 6 -C 20 aryl group. Examples of comonomers include ethylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-octene, 1-decene, and 1-dodecene. In some embodiments, the comonomer is present at about 5% by weight to about 25% by weight of the interpolymer. In one embodiment, a propylene-ethylene interpolymer is used.
[0041] Other examples of polymers which may be used in the present disclosure include homopolymers and copolymers (including elastomers) of an olefin such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-octene, 1-decene, and 1-dodecene as typically represented by polyethylene, polypropylene, poly-1-butene, poly-3-methyl-1-butene, poly-3-methyl-1-pentene, poly-4-methyl-1-pentene, ethylene-propylene copolymer, ethylene-1-butene copolymer, and propylene-1-butene copolymer; copolymers (including elastomers) of an alpha-olefin with a conjugated or non-conjugated diene as typically represented by ethylene-butadiene copolymer and ethylene-ethylidene norbornene copolymer; and polyolefins (including elastomers) such as copolymers of two or more alpha-olefins with a conjugated or non-conjugated diene as typically represented by ethylene-propylene-butadiene copolymer, ethylene-propylene-dicyclopentadiene copolymer, ethylene-propylene-1,5-hexadiene copolymer, and ethylene-propylene-ethylidene norbornene copolymer; ethylene-vinyl compound copolymers such as ethylene-vinyl acetate copolymers with N-methylol functional comonomers, ethylene-vinyl alcohol copolymers with N-methylol functional comonomers, ethylene-vinyl chloride copolymer, ethylene acrylic acid or ethylene-(meth)acrylic acid copolymers, and ethylene-(meth)acrylate copolymer; styrenic copolymers (including elastomers) such as polystyrene, ABS, acrylonitrile-styrene copolymer, methylstyrene-styrene copolymer; and styrene block copolymers (including elastomers) such as styrene-butadiene copolymer and hydrate thereat, and styrene-isoprene-styrene triblock copolymer; polyvinyl compounds such as polyvinyl chloride, polyvinylidene chloride, vinyl chloride-vinylidene chloride copolymer, polymethyl acrylate, and polymethyl methacrylate; polyamides such as nylon 6, nylon 6,6, and nylon 12; thermoplastic polyesters such as polyethylene terephthalate and polybutylene terephthalate; polycarbonate, polyphenylene oxide, and the like. These resins may be used either alone or in combinations of two or more.
[0042] In particular embodiments, polyolefins such as polypropylene, polyethylene, and copolymers thereof and blends thereof, as well as ethylene-propylene-diene terpolymers may be used. In some embodiments, the olefinic polymers include homogeneous polymers described in U.S. Pat. No. 3,645,992 by Elston; high density polyethylene (HDPE) as described in U.S. Pat. No. 4,076,698 to Anderson; heterogeneously branched linear low density polyethylene (LLDPE); heterogeneously branched ultra low linear density (ULDPE); homogeneously branched, linear ethylene/alpha-olefin copolymers; homogeneously branched, substantially linear ethylene/alpha-olefin polymers which can be prepared, for example, by a process disclosed in U.S. Pat. Nos. 5,272,236 and 5,278,272, the disclosure of which process is incorporated herein by reference; heterogeneously branched linear ethylene/alpha olefin polymers; and high pressure, free radical polymerized ethylene polymers and copolymers such as low density polyethylene (LDPE).
[0043] In another embodiment, the polymers may include an ethylene-carboxylic acid copolymer, such as, ethylene-vinyl acetate (EVA) copolymers, ethylene-acrylic acid (EAA) and ethylene-methacrylic acid copolymers such as, for example, those available under the tradenames PRIMACOR™ from the Dow Chemical Company, NUCREL™ from DuPont, and ESCOR™ from ExxonMobil, and described in U.S. Pat. Nos. 4,599,392, 4,988,781, and 59,384,373, each of which is incorporated herein by reference in its entirety. Exemplary polymers include polypropylene, (both impact modifying polypropylene, isotactic polypropylene, atactic polypropylene, and random ethylene/propylene copolymers), various types of polyethylene, including high pressure, free-radical LDPE, Ziegler Natta LLDPE, metallocene PE, including multiple reactor PE (“in reactor”) blends of Ziegler-Natta PE and metallocene PE, such as products disclosed in U.S. Pat. Nos. 6,545,088, 6,538,070, 6,566,446, 5,844,045, 5,869,575, and 6,448,341. Homogeneous polymers such as olefin plastomers and elastomers, ethylene and propylene-based copolymers (for example polymers available under the trade designation VERSIFY™ available from The Dow Chemical Company and VISTAMAXX™ available from ExxonMobil) may also be useful in some embodiments. Of course, blends of polymers may be used as well. In some embodiments, the blends include two different Ziegler-Natta polymers. In other embodiments, the blends may include blends of a Ziegler-Natta and a metallocene polymer. In still other embodiments, the thermoplastic resin used herein may be a blend of two different metallocene polymers.
[0044] In one particular embodiment, the polymer may comprise an alpha-olefin interpolymer of ethylene with a comonomer comprising an alkene, such as 1-octene. The ethylene and octene copolymer may be present alone or in combination with another polymer, such as ethylene-acrylic acid copolymer. When present together, the weight ratio between the ethylene and octene copolymer and the ethylene-acrylic acid copolymer may be from about 1:10 to about 10:1, such as from about 3:2 to about 2:3. The polymer, such as the ethylene-octene copolymer, may have a crystallinity of less than about 50%, such as less than about 25%. In some embodiments, the crystallinity of the polymer may be from 5 to 35 percent. In other embodiments, the crystallinity may range from 7 to 20 percent.
[0045] In one particular embodiment, the polymer may comprise at least one low density polyethylene (LDPE). The polymer may comprise LDPE made in autoclave processes or tubular processes. Suitable LDPE for this embodiment is defined elsewhere in this document.
[0046] In one particular embodiment, the polymer may comprise at least two low density polyethylenes. The polymer may comprise LDPE made in autoclave processes, tubular processes, or combinations thereof. Suitable LDPEs for this embodiment are defined elsewhere in this document.
[0047] In one particular embodiment, the polymer may comprise an alpha-olefin interpolymer of ethylene with a comonomer comprising an alkene, such as 1-octene. The ethylene and octene copolymer may be present alone or in combination with another polymer, such as a low density polyethylene (LDPE). When present together, the weight ratio between the ethylene and octene copolymer and the LDPE may be from about 60:40 to about 97:3, such as from about 80:20 to about 96:4. The polymer, such as the ethylene-octene copolymer, may have a crystallinity of less than about 50%, such as less than about 25%. In some embodiments, the crystallinity of the polymer may be from 5 to 35 percent. In other embodiments, the crystallinity may range from 7 to 20 percent. Suitable LDPEs for this embodiment are defined elsewhere in this document.
[0048] In one particular embodiment, the polymer may comprise an alpha-olefin interpolymer of ethylene with a comonomer comprising an alkene, such as 1-octene. The ethylene and octene copolymer may be present alone or in combination with at least two other polymers from the group: low density polyethylene, medium density polyethylene, and high density polyethylene (HDPE). When present together, the weight ratio between the ethylene and octene copolymer, the LDPE, and the HDPE are such that the composition comprises one component from 3 to 97% by weight of the total composition and the remainder comprises the other two components. The polymer, such as the ethylene-octene copolymer, may have a crystallinity of less than about 50%, such as less than about 25%. In some embodiments, the crystallinity of the polymer may be from 5 to 35 percent. In other embodiments, the crystallinity may range from 7 to 20 percent.
[0049] Embodiments disclosed herein may also include a polymeric component that may include at least one multi-block olefin interpolymer. Suitable multi-block olefin interpolymers may include those described in U.S. Provisional Patent Application No. 60/818,911, for example. The term “multi-block copolymer” or refers to a polymer comprising two or more chemically distinct regions or segments (referred to as “blocks”) preferably joined in a linear manner, that is, a polymer comprising chemically differentiated units which are joined end-to-end with respect to polymerized ethylenic functionality, rather than in pendent or grafted fashion. In certain embodiments, the blocks differ in the amount or type of comonomer incorporated therein, the density, the amount of crystallinity, the crystallite size attributable to a polymer of such composition, the type or degree of tacticity (isotactic or syndiotactic), regio-regularity or regio-irregularity, the amount of branching, including long chain branching or hyper-branching, the homogeneity, or any other chemical or physical property. The multi-block copolymers are characterized by unique distributions of polydispersity index (PDI or M w /M n ), block length distribution, and/or block number distribution due to the unique process making of the copolymers. More specifically, when produced in a continuous process, embodiments of the polymers may possess a PDI ranging from about 1.7 to about 8; from about 1.7 to about 3.5 in other embodiments; from about 1.7 to about 2.5 in other embodiments; and from about 1.8 to about 2.5 or from about 1.8 to about 2.1 in yet other embodiments. When produced in a batch or semi-batch process, embodiments of the polymers may possess a PDI ranging from about 1.0 to about 2.9; from about 1.3 to about 2.5 in other embodiments; from about 1.4 to about 2.0 in other embodiments; and from about 1.4 to about 1.8 in yet other embodiments.
[0050] One example of the multi-block olefin interpolymer is an ethylene/α-olefin block interpolymer. Another example of the multi-block olefin interpolymer is a propylene/α-olefin interpolymer. The following description focuses on the interpolymer as having ethylene as the majority monomer, but applies in a similar fashion to propylene-based multi-block interpolymers with regard to general polymer characteristics.
[0051] The ethylene/α-olefin multi-block interpolymers may comprise ethylene and one or more co-polymerizable α-olefin comonomers in polymerized form, characterized by multiple (i.e., two or more) blocks or segments of two or more polymerized monomer units differing in chemical or physical properties (block interpolymer), preferably a multi-block interpolymer. In some embodiments, the multi-block interpolymer may be represented by the following formula:
[0000] (AB) n
[0000] where n is at least 1, preferably an integer greater than 1, such as 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, or higher; “A” represents a hard block or segment; and “B” represents a soft block or segment. Preferably, A′ s and B′ s are linked in a linear fashion, not in a branched or a star fashion. “Hard” segments refer to blocks of polymerized units in which ethylene is present in an amount greater than 95 weight percent in some embodiments, and in other embodiments greater than 98 weight percent. In other words, the comonomer content in the hard segments is less than 5 weight percent in some embodiments, and in other embodiments, less than 2 weight percent of the total weight of the hard segments. In some embodiments, the hard segments comprise all or substantially all ethylene. “Soft” segments, on the other hand, refer to blocks of polymerized units in which the comonomer content is greater than 5 weight percent of the total weight of the soft segments in some embodiments, greater than 8 weight percent, greater than 10 weight percent, or greater than 15 weight percent in various other embodiments. In some embodiments, the comonomer content in the soft segments may be greater than 20 weight percent, greater than 25 eight percent, greater than 30 weight percent, greater than 35 weight percent, greater than 40 weight percent, greater than 45 weight percent, greater than 50 weight percent, or greater than 60 weight percent in various other embodiments.
[0052] In some embodiments, A blocks and B blocks are randomly distributed along the polymer chain. In other words, the block copolymers do not have a structure like:
[0000] AAA-AA-BBB-BB
[0053] In other embodiments, the block copolymers do not have a third block. In still other embodiments, neither block A nor block B comprises two or more segments (or sub-blocks), such as a tip segment.
[0054] The multi-block interpolymers may be characterized by an average block index, ABI, ranging from greater than zero to about 1.0 and a molecular weight distribution, M w /M n , greater than about 1.3. The average block index, ABI, is the weight average of the block index (“BI”) for each of the polymer fractions obtained in preparative TREF from 20° C. and 110° C., with an increment of 5° C.:
[0000] ABI=Σ( w i BI i )
[0000] where BI i is the block index for the i th fraction of the multi-block interpolymer obtained in preparative TREF, and w i is the weight percentage of the i th fraction.
[0055] Similarly, the square root of the second moment about the mean, hereinafter referred to as the second moment weight average block index, may be defined as follows:
[0000]
2
nd
moment
weight
average
B
I
=
Σ
(
w
i
(
B
I
i
-
ABI
)
2
)
(
N
-
1
)
Σ
w
i
N
[0056] For each polymer fraction, BI is defined by one of the two following equations (both of which give the same BI value):
[0000]
B
I
=
1
/
T
X
-
1
/
T
XO
1
/
T
A
-
1
/
T
AB
or
B
I
=
-
Ln
P
X
-
Ln
P
XO
Ln
P
A
-
Ln
P
AB
[0000] where T x is the analytical temperature rising elution fractionation (ATREF) elution temperature for the i th fraction (preferably expressed in Kelvin), P x is the ethylene mole fraction for the i th fraction, which may be measured by NMR or IR as described below. P AB is the ethylene mole fraction of the whole ethylene/α-olefin interpolymer (before fractionation), which also may be measured by NMR or IR. T A and P A are the ATREF elution temperature and the ethylene mole fraction for pure “hard segments” (which refer to the crystalline segments of the interpolymer). As an approximation or for polymers where the “hard segment” composition is unknown, the T A and P A values are set to those for high density polyethylene homopolymer.
[0057] T AB is the ATREF elution temperature for a random copolymer of the same composition (having an ethylene mole fraction of P AB ) and molecular weight as the multi-block interpolymer. T AB may be calculated from the mole fraction of ethylene (measured by NMR) using the following equation:
[0000] Ln P AB =α/T AB +β
[0000] where α and β are two constants which may be determined by a calibration using a number of well characterized preparative TREF fractions of a broad composition random copolymer and/or well characterized random ethylene copolymers with narrow composition. It should be noted that α and β may vary from instrument to instrument. Moreover, one would need to create an appropriate calibration curve with the polymer composition of interest, using appropriate molecular weight ranges and comonomer type for the preparative TREF fractions and/or random copolymers used to create the calibration. There is a slight molecular weight effect. If the calibration curve is obtained from similar molecular weight ranges, such effect would be essentially negligible. In some embodiments, random ethylene copolymers and/or preparative TREF fractions of random copolymers satisfy the following relationship:
[0000] Ln P=− 237.83 /T ATREF +0.639
[0058] The above calibration equation relates the mole fraction of ethylene, P, to the analytical TREF elution temperature, T ATREF , for narrow composition random copolymers and/or preparative TREF fractions of broad composition random copolymers. T XO is the ATREF temperature for a random copolymer of the same composition and having an ethylene mole fraction of P x . T XO may be calculated from Ln P X =α/T XO +β. Conversely, P XO is the ethylene mole fraction for a random copolymer of the same composition and having an ATREF temperature of T X , which may be calculated from Ln P XO =α/T X +β
[0059] Once the block index (BI) for each preparative TREF fraction is obtained, the weight average block index, ABI, for the whole polymer may be calculated. In some embodiments, ABI is greater than zero but less than about 0.4 or from about 0.1 to about 0.3. In other embodiments, ABI is greater than about 0.4 and up to about 1.0. Preferably, ABI should be in the range of from about 0.4 to about 0.7, from about 0.5 to about 0.7, or from about 0.6 to about 0.9. In some embodiments, ABI is in the range of from about 0.3 to about 0.9, from about 0.3 to about 0.8, or from about 0.3 to about 0.7, from about 0.3 to about 0.6, from about 0.3 to about 0.5, or from about 0.3 to about 0.4. In other embodiments, ABI is in the range of from about 0.4 to about 1.0, from about 0.5 to about 1.0, or from about 0.6 to about 1.0, from about 0.7 to about 1.0, from about 0.8 to about 1.0, or from about 0.9 to about 1.0.
[0060] Another characteristic of the multi-block interpolymer is that the interpolymer may comprise at least one polymer fraction which may be obtained by preparative TREF, wherein the fraction has a block index greater than about 0.1 and up to about 1.0 and the polymer having a molecular weight distribution, M w /M n , greater than about 1.3. In some embodiments, the polymer fraction has a block index greater than about 0.6 and up to about 1.0, greater than about 0.7 and up to about 1.0, greater than about 0.8 and up to about 1.0, or greater than about 0.9 and up to about 1.0. In other embodiments, the polymer fraction has a block index greater than about 0.1 and up to about 1.0, greater than about 0.2 and up to about 1.0, greater than about 0.3 and up to about 1.0, greater than about 0.4 and up to about 1.0, or greater than about 0.4 and up to about 1.0. In still other embodiments, the polymer fraction has a block index greater than about 0.1 and up to about 0.5, greater than about 0.2 and up to about 0.5, greater than about 0.3 and up to about 0.5, or greater than about 0.4 and up to about 0.5. In yet other embodiments, the polymer fraction has a block index greater than about 0.2 and up to about 0.9, greater than about 0.3 and up to about 0.8, greater than about 0.4 and up to about 0.7, or greater than about 0.5 and up to about 0.6.
[0061] Ethylene α-olefin multi-block interpolymers used in embodiments of the invention may be interpolymers of ethylene with at least one C 3 -C 20 α-olefin. The interpolymers may further comprise C 4 -C 18 diolefin and/or alkenylbenzene. Suitable unsaturated comonomers useful for polymerizing with ethylene include, for example, ethylenically unsaturated monomers, conjugated or non-conjugated dienes, polyenes, alkenylbenzenes, etc. Examples of such comonomers include C 3 -C 20 α-olefins such as propylene, isobutylene, 1-butene, 1-hexene, 1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, and the like. 1-Butene and 1-octene are especially preferred. Other suitable monomers include styrene, halo- or alkyl-substituted styrenes, vinylbenzocyclobutane, 1,4-hexadiene, 1,7-octadiene, and naphthenics (such as cyclopentene, cyclohexene, and cyclooctene, for example).
[0062] The multi-block interpolymers disclosed herein may be differentiated from conventional, random copolymers, physical blends of polymers, and block copolymers prepared via sequential monomer addition, fluxional catalysts, and anionic or cationic living polymerization techniques. In particular, compared to a random copolymer of the same monomers and monomer content at equivalent crystallinity or modulus, the interpolymers have better (higher) heat resistance as measured by melting point, higher TMA penetration temperature, higher high-temperature tensile strength, and/or higher high-temperature torsion storage modulus as determined by dynamic mechanical analysis. Properties of infill may benefit from the use of embodiments of the multi-block interpolymers, as compared to a random copolymer containing the same monomers and monomer content, the multi-block interpolymers have lower compression set, particularly at elevated temperatures, lower stress relaxation, higher creep resistance, higher tear strength, higher blocking resistance, faster setup due to higher crystallization (solidification) temperature, higher recovery (particularly at elevated temperatures), better abrasion resistance, higher refractive force, and better oil and filler acceptance.
[0063] Other olefin interpolymers include polymers comprising monovinylidene aromatic monomers including styrene, o-methyl styrene, p-methyl styrene, t-butylstyrene, and the like. In particular, interpolymers comprising ethylene and styrene may be used. In other embodiments, copolymers comprising ethylene, styrene and a C 3 -C 20 α olefin, optionally comprising a C 4 -C 20 diene, may be used.
[0064] Suitable non-conjugated diene monomers may include straight chain, branched chain or cyclic hydrocarbon diene having from 6 to 15 carbon atoms. Examples of suitable non-conjugated dienes include, but are not limited to, straight chain acyclic dienes, such as 1,4-hexadiene, 1,6-octadiene, 1,7-octadiene, 1,9-decadiene, branched chain acyclic dienes, such as 5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene; 3,7-dimethyl-1,7-octadiene and mixed isomers of dihydromyricene and dihydroocinene, single ring alicyclic dienes, such as 1,3-cyclopentadiene; 1,4-cyclohexadiene; 1,5-cyclooctadiene and 1,5-cyclododecadiene, and multi-ring alicyclic fused and bridged ring dienes, such as tetrahydroindene, methyl tetrahydroindene, dicyclopentadiene, bicyclo-(2,2,1)-hepta-2,5-diene; alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornenes, such as 5-methylene-2-norbornene (MNB); 5-propenyl-2-norbornene, 5-isopropylidene-2-norbornene, 5-(4-cyclopentenyl)-2-norbornene, 5-cyclohexylidene-2-norbornene, 5-vinyl-2-norbornene, and norbornadiene. Of the dienes typically used to prepare EPDMs, the particularly preferred dienes are 1,4-hexadiene (HD), 5-ethylidene-2-norbornene (ENB), 5-vinylidene-2-norbornene (VNB), 5-methylene-2-norbornene (MNB), and dicyclopentadiene (DCPD).
[0065] One class of desirable polymers that may be used in accordance with embodiments disclosed herein includes elastomeric interpolymers of ethylene, a C 3 -C 20 α-olefin, especially propylene, and optionally one or more diene monomers. Preferred α-olefins for use in this embodiment are designated by the formula CH 2 ═CHR*, where R* is a linear or branched alkyl group of from 1 to 12 carbon atoms. Examples of suitable α-olefins include, but are not limited to, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene. A particularly preferred α-olefin is propylene. The propylene based polymers are generally referred to in the art as EP or EPDM polymers. Suitable dienes for use in preparing such polymers, especially multi-block EPDM type polymers include conjugated or non-conjugated, straight or branched chain-, cyclic- or polycyclic-dienes comprising from 4 to 20 carbons. Preferred dienes include 1,4-pentadiene, 1,4-hexadiene, 5-ethylidene-2-norbornene, dicyclopentadiene, cyclohexadiene, and 5-butylidene-2-norbornene. A particularly preferred diene is 5-ethylidene-2-norbornene.
[0066] The polymers (homopolymers, copolymers, interpolymers and multi-block interpolymers) described herein may have a melt index, I 2 , from 0.01 to 2000 g/10 minutes in some embodiments; from 0.01 to 1000 g/10 minutes in other embodiments; from 0.01 to 500 g/10 minutes in other embodiments; and from 0.01 to 100 g/10 minutes in yet other embodiments. In certain embodiments, the polymers may have a melt index, I 2 , from 0.01 to 10 g/10 minutes, from 0.5 to 50 g/10 minutes, from 1 to 30 g/10 minutes, from 1 to 6 g/10 minutes or from 0.3 to 10 g/10 minutes. In certain embodiments, the melt index for the polymers may be approximately 1 g/10 minutes, 3 g/10 minutes or 5 g/10 minutes. In other embodiments, the polymers may have a melt index greater than 20 dg/min; greater than 40 dg/min in other embodiments; and greater than 60 dg/min in yet other embodiments.
[0067] The polymers described herein may have molecular weights, M w , from 1,000 g/mole to 5,000,000 g/mole in some embodiments; from 1000 g/mole to 1,000,000 in other embodiments; from 10,000 g/mole to 500,000 g/mole in other embodiments; and from 10,000 g/mole to 300,000 g/mole in yet other embodiments. The density of the polymers described herein may be from 0.80 to 0.99 g/cm 3 in some embodiments; for ethylene containing polymers from 0.85 g/cm 3 to 0.97 g/cm 3 ; in some embodiments between 0.87 g/cm 3 and 0.94 g/cm 3 .
[0068] In some embodiments, the polymers described herein may have a tensile strength above 10 MPa; a tensile strength >11 MPa in other embodiments; and a tensile strength >13 MPa in yet other embodiments. In some embodiments, the polymers described herein may have an elongation at break of at least 600 percent at a crosshead separation rate of 11 cm/minute; at least 700 percent in other embodiments; at least 800 percent in other embodiments; and at least 900 percent in yet other embodiments.
[0069] In some embodiments, the polymers described herein may have a storage modulus ratio, G′(25° C.)/G′(100° C.), from 1 to 50; from 1 to 20 in other embodiments; and from 1 to 10 in yet other embodiments. In some embodiments, the polymers may have a 70° C. compression set of less than 80 percent; less than 70 percent in other embodiments; less than 60 percent in other embodiments; and, less than 50 percent, less than 40 percent, down to a compression set of 0 percent in yet other embodiments.
[0070] In some embodiments, the ethylene/α-olefin interpolymers may have a heat of fusion of less than 85 J/g. In other embodiments, the ethylene/α-olefin interpolymer may have a pellet blocking strength of equal to or less than 100 pounds/foot 2 (4800 Pa); equal to or less than 50 lbs/ft 2 (2400 Pa) in other embodiments; equal to or less than 5 lbs/ft 2 (240 Pa), and as low as 0 lbs/ft 2 (0 Pa) in yet other embodiments.
[0071] In some embodiments, block polymers made with two catalysts incorporating differing quantities of comonomer may have a weight ratio of blocks formed thereby ranging from 95:5 to 5:95. The elastomeric interpolymers, in some embodiments, have an ethylene content of from 20 to 90 percent, a diene content of from 0.1 to 10 percent, and an α-olefin content of from 10 to 80 percent, based on the total weight of the polymer. In other embodiments, the multi-block elastomeric polymers have an ethylene content of from 60 to 90 percent, a diene content of from 0.1 to 10 percent, and an α-olefin content of from 10 to 40 percent, based on the total weight of the polymer. In other embodiments, the interpolymer may have a Mooney viscosity (ML (1+4) 125° C.) ranging from 1 to 250. In other embodiments, such polymers may have an ethylene content from 65 to 75 percent, a diene content from 0 to 6 percent, and an α-olefin content from 20 to 35 percent.
[0072] In certain embodiments, the polymer may be a propylene-ethylene copolymer or interpolymer having an ethylene content between 5 and 20% by weight and a melt flow rate (230° C. with 2.16 kg weight) from 0.5 to 300 g/10 min. In other embodiments, the propylene-ethylene copolymer or interpolymer may have an ethylene content between 9 and 12% by weight and a melt flow rate (230° C. with 2.16 kg weight) from 1 to 100 g/10 min.
[0073] In some particular embodiments, the polymer is a propylene-based copolymer or interpolymer. In some embodiments, a propylene/ethylene copolymer or interpolymer is characterized as having substantially isotactic propylene sequences. The term “substantially isotactic propylene sequences” and similar terms mean that the sequences have an isotactic triad (mm) measured by 13 C NMR of greater than about 0.85, preferably greater than about 0.90, more preferably greater than about 0.92 and most preferably greater than about 0.93. Isotactic triads are well-known in the art and are described in, for example, U.S. Pat. No. 5,504,172 and WO 00/01745, which refer to the isotactic sequence in terms of a triad unit in the copolymer molecular chain determined by 13 C NMR spectra. In other particular embodiments, the ethylene-α olefin copolymer may be ethylene-butene, ethylene-hexene, or ethylene-octene copolymers or interpolymers. In other particular embodiments, the propylene-α olefin copolymer may be a propylene-ethylene or a propylene-ethylene-butene copolymer or interpolymer.
[0074] The polymers described herein (homopolymers, copolymers, interpolymers, multi-block interpolymers) may be produced using a single site catalyst and may have a weight average molecular weight of from about 15,000 to about 5 million, such as from about 20,000 to about 1 million. The molecular weight distribution of the polymer may be from about 1.01 to about 80, such as from about 1.5 to about 40, such as from about 1.8 to about 20.
[0075] In some embodiments, the polymer may have a Shore A hardness from 30 to 100. In other embodiments, the polymer may have a Shore A hardness from 40 to 90; from 30 to 80 in other embodiments; and from 40 to 75 in yet other embodiments.
[0076] The olefin polymers, copolymers, interpolymers, and multi-block interpolymers may be functionalized by incorporating at least one functional group in its polymer structure. Exemplary functional groups may include, for example, ethylenically unsaturated mono- and di-functional carboxylic acids, ethylenically unsaturated mono- and di-functional carboxylic acid anhydrides, salts thereof and esters thereof. Such functional groups may be grafted to an olefin polymer, or it may be copolymerized with ethylene and an optional additional comonomer to form an interpolymer of ethylene, the functional comonomer and optionally other comonomer(s). Means for grafting functional groups onto polyethylene are described for example in U.S. Pat. Nos. 4,762,890, 4,927,888, and 4,950,541, the disclosures of which are incorporated herein by reference in their entirety. One particularly useful functional group is maleic anhydride.
[0077] The amount of the functional group present in the functional polymer may vary. The functional group may be present in an amount of at least about 1.0 weight percent in some embodiments; at least about 5 weight percent in other embodiments; and at least about 7 weight percent in yet other embodiments. The functional group may be present in an amount less than about 40 weight percent in some embodiments; less than about 30 weight percent in other embodiments; and less than about 25 weight percent in yet other embodiments.
[0078] The foam sheets according to embodiments disclosed herein may include a single layer or multiple layers as desired. The foam articles may be produced in any manner so as to result in at least one foam layer. The foam layers described herein may be made by a pressurized melt processing method such as an extrusion method. The extruder may be a tandem system, a single screw extruder, a twin screw extruder, etc. The extruder may be equipped with multilayer annular dies, flat film dies and feedblocks, multi-layer feedblocks such as those disclosed in U.S. Pat. No. 4,908,278 (Bland et al.), multi-vaned or multi-manifold dies such as a 3-layer vane die available from Cloeren, Orange, Tex. A foamable composition may also be made by combining a chemical blowing agent and polymer at a temperature below the decomposition temperature of the chemical blowing agent, and then later foamed. In some embodiments, the foam may be coextruded with one or more barrier layers.
[0079] One method of producing the foams described herein is by using an extruder, as mentioned above. In this case, the foamable mixture (polymer+blowing agent) is extruded. As the mixture exits an extruder die and upon exposure to reduced pressure, the fugitive gas nucleates and forms cells within the polymer to create a foam article. The resulting foam article may then be deposited onto a temperature-controlled casting drum. The casting drum speed (i.e., as produced by the drum RPM) can affect the overall thickness of the foam article. As the casting roll speed increases, the overall thickness of the foam article can decrease. However, the barrier layer thickness at the die exit, which is where foaming occurs, is the diffusion length for the system. As the foam article is stretched and quenched on the casting drum, the barrier layer thickness may decrease until the foam article solidifies. In other words, it is the barrier layer diffusion length (i.e., thickness) at the die exit that is the important factor in controlling the diffusion of the fugitive gas.
[0080] Blowing agents suitable for use in forming the foams described herein may be physical blowing agents, which are typically the same material as the fugitive gas, e.g., CO 2 , or a chemical blowing agent, which produces the fugitive gas. More than one physical or chemical blowing agent may be used and physical and chemical blowing agents may be used together.
[0081] Physical blowing agents useful in the present invention include any naturally occurring atmospheric material which is a vapor at the temperature and pressure at which the foam exits the die. The physical blowing agent may be introduced, i.e., injected into the polymeric material as a gas, a supercritical fluid, or liquid, preferably as a supercritical fluid or liquid, most preferably as a liquid. The physical blowing agents used will depend on the properties sought in the resulting foam articles. Other factors considered in choosing a blowing agent are its toxicity, vapor pressure profile, ease of handling, and solubility with regard to the polymeric materials used. Non-flammable, non-toxic, non-ozone depleting blowing are preferred because they are easier to use, e.g., fewer environmental and safety concerns, and are generally less soluble in thermoplastic polymers. Suitable physical blowing agents include, e.g., carbon dioxide, nitrogen, SF.sub.6, nitrous oxide, perfluorinated fluids, such as C 2 F 6 , argon, helium, noble gases, such as xenon, air (nitrogen and oxygen blend), and blends of these materials.
[0082] Chemical blowing agents that may be used in the present invention include, e.g., a sodium bicarbonate and citric acid blend, dinitrosopentamethylenetetramine, p-toluenesulfonyl hydrazide, 4-4 1 -oxybis(benzenesulfonyl hydrazide, azodicarbonamide (1,1′-azobisformamide), p-toluenesulfonyl semicarbazide, 5-phenyltetrazole, 5-phenyltetrazole analogues, diisopropylhydrazodicarboxylate, 5-phenyl-3,6-dihydro-1,3,4-oxadiazin-2-one, and sodium borohydride. Preferably, the blowing agents are, or produce, one or more fugitive gases having a vapor pressure of greater than 0.689 MPa at 0° C.
[0083] The total amount of the blowing agent used depends on conditions such as extrusion-process conditions at mixing, the blowing agent being used, the composition of the extrudate, and the desired density of the foamed article. The extrudate is defined herein as including the blowing agent blend, a polyolefin resin(s), and any additives. For a foam having a density of from about 1 to about 15 lb/ft 3 , the extrudate typically comprises from about 18 to about 1 wt of blowing agent. In other embodiments, 1% to 10% of blowing agent may be used.
[0084] The blowing agent blend used in the present invention comprises less than about 99 mol % isobutane. The blowing agent blend generally comprises from about 10 mol % to about 60 or 75 mol % isopentane. The blowing agent blend more typically comprises from about 15 mol % to about 40 mol % isopentane. More specifically, the blowing agent blend comprises from about 25 or 30 mol % to about 40 mol % isobutane. The blowing agent blend generally comprises at least about 15 or 30 mol % of co-blowing agent(s). More specifically, the blowing agent blend comprises from about 40 to about 85 or 90 mol % of co-blowing agent(s). The blowing agent blend more typically comprises from about 60 mol % to about 70 or 75 mol % of co-blowing agent(s).
[0085] A nucleating agent or combination of such agents may be employed in the present invention for advantages, such as its capability for regulating cell formation and morphology. A nucleating agent, or cell size control agent, may be any conventional or useful nucleating agent(s). The amount of nucleating agent used depends upon the desired cell size, the selected blowing agent blend, and the desired foam density. The nucleating agent is generally added in amounts from about 0.02 to about 20 wt % of the polyolefin resin composition.
[0086] Some contemplated nucleating agents include inorganic materials (in small particulate form), such as clay, talc, silica, and diatomaceous earth. Other contemplated nucleating agents include organic nucleating agents that decompose or react at the heating temperature within an extruder to evolve gases, such as carbon dioxide, water, and/or nitrogen. One example of an organic nucleating agent is a combination of an alkali metal salt of a polycarboxylic acid with a carbonate or bicarbonate. Some examples of alkali metal salts of a polycarboxylic acid include, but are not limited to, the monosodium salt of 2,3-dihydroxy-butanedioic acid (commonly referred to as sodium hydrogen tartrate), the monopotassium salt of butanedioic acid (commonly referred to as potassium hydrogen succinate), the trisodium and tripotassium salts of 2-hydroxy-1,2,3-propanetricarboxylic acid (commonly referred to as sodium and potassium citrate, respectively), and the disodium salt of ethanedioic acid (commonly referred to as sodium oxalate), or polycarboxylic acid such as 2-hydroxy-1,2,3-propanetricarboxylic acid. Some examples of a carbonate or a bicarbonate include, but are not limited to, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, and calcium carbonate.
[0087] It is contemplated that mixtures of different nucleating agents may be added in the present invention. Some more desirable nucleating agents include talc, crystalline silica, and a stoichiometric mixture of citric acid and sodium bicarbonate (the stoichiometric mixture having a 1 to 100 percent concentration where the carrier is a suitable polymer such as polyethylene). Talc may be added in a carrier or in a powder form.
[0088] Gas permeation agents or stability control agents may be employed in the present invention to assist in preventing or inhibiting collapsing of the foam. The stability control agents suitable for use in the present invention may include the partial esters of long-chain fatty acids with polyols described in U.S. Pat. No. 3,644,230, saturated higher alkyl amines, saturated higher fatty acid amides, complete esters of higher fatty acids such as those described in U.S. Pat. No. 4,214,054, and combinations thereof described in U.S. Pat. No. 5,750,584.
[0089] The partial esters of fatty acids that may be desired as a stability control agent include the members of the generic class known as surface active agents or surfactants. A preferred class of surfactants includes a partial ester of a fatty acid having 12 to 18 carbon atoms and a polyol having three to six hydroxyl groups. More preferably, the partial esters of a long chain fatty acid with a polyol component of the stability control agent are glycerol monostearate, glycerol distearate or mixtures thereof. It is contemplated that other gas permeation agents or stability control agents may be employed in the present invention to assist in preventing or inhibiting collapsing of the foam.
[0090] Additives
[0091] If desired, fillers, colorants, light and heat stabilizers, anti-oxidants, acid scavengers, flame retardants, processing aids, extrusion aids, and foaming additives may be used in making the foam. The foam of the invention may contain filler materials in amounts, depending on the application for which they are designed, ranging from about 2-100 percent (dry basis) of the weight of the polymer component. These optional ingredients may include, but are not limited to, calcium carbonate, titanium dioxide powder, polymer particles, hollow glass spheres, polymeric fibers such as polyolefin based staple monofilaments and the like.
[0092] In selected embodiments, foams useful for disclosed embodiments may have thickness between 1 and 500 mm, and in some embodiments, 5 to 100 mm, and in some embodiments 8 and 30 mm. In selected embodiments foams may have a density between about 20 and 600 kg/m 3 , preferably 25 to 300 kg/m 3 , and more preferably, 30 to 150 kg/m 3 . In selected embodiments, foams may have a cell size between about 0.1 to 6 mm, preferably 0.2 to 4.5 mm, and more preferably 0.2 to 3 mm.
[0093] In some embodiments, the foam layer may be perforated in order to facilitate drainage, so that in the event of rain, water may drain off of the playing surface.
[0094] In some embodiments, the above described foams may be used as a shock absorbing layer in a synthetic turf. Additionally, tests may be performed to analyze temperature performance and aging, as well as the bounce and spin properties of the resulting turf. Briefly, the significant tests & desired results for artificial turf performance as specified by the FIFA Quality Concept Manual (March 2006 Edition) are shown in the below table. Those having ordinary skill in the art will appreciate that this is but one use of the foams described herein, and that the artificial turf and foams described herein may be useful in a number of other applications an a number of other sports, such as rugby and field hockey, for example.
[0000]
LABORATORY TESTS - BALL/SURFACE INTERACTION
Requirements
FIFA
Test
Test
Test Conditions
Recommended**
FIFA
Property
Method
Method
Preparation
Temp
Condition
(best ranking)
Recommended*
Vertical ball
FIFA
Pre-
23° C.
Dry
0.60 m-0.85 m
0.60 m-1 m
rebound
01/05-01 &
conditioning
Wet
—
FIFA
Simulated
23° C.
Dry
0.60 m-1 m
09/05-01
Wear
Shock
FIFA
Flat foot
Pre-
23° C.
Dry
60%-70%
55%-70%
absorption
04/05-01 &
Mean
conditioning
Wet
—
FIFA
2 nd /3 rd
Simulated
23° C.
Dry
55%-70%
10/05-01
impact
Wear
—
40° C.
Dry
—
Flat Foot
—
−5° C.
Frozen
60%-70%
—
1 st
impact
Vertical
FIFA
Flat foot
Pre-
23° C.
Dry
4 mm-8 mm
4 mm-9 mm
deformation
05/05-01 &
Mean
conditioning
Wet
—
FIFA
2 nd /3 rd
Simulated
23° C.
Dry
4 mm-9 mm
10/05-01
impact
Wear
[0095] Shock Absorption
[0096] Principle: A mass (20 Kgs) falls, as discussed in the FIFA Quality Concept Manual (March 2006 Edition), which is incorporated by reference in its entirety. The maximum force applied is recorded. The % reduction in this force relative to the maximum force measured on a concrete surface is reported as ‘Force Reduction’.
[0097] FIFA Requirement:
[0098] FIFA 2 Star: 60%-70%
[0099] FIFA 1 Star: 55%-70%
[0100] Vertical Deformation
[0101] Principle A mass is allowed to fall onto a spring that rests and the maximum deformation of the surface is determined.
[0102] FIFA Requirement:
[0103] FIFA 2 Star: 4 mm-8 mm
[0104] FIFA 1 Star: 4 mm-9 mm
EXAMPLES
[0105] The usefulness of polyolefin resins having selected foam densities and thicknesses is investigated. Specifically, a number of polyethylene resins, commercially available from The Dow Chemical Company, Midland, Mich. are studied. Table 1 and Table 2 show a number of the compounds used. In Table 1, the performance of crosslinked polyethylene (comparative examples 1c-4c) versus non-crosslinked polyethylene (examples 1-4) is investigated. Specifically, with respect to Table 1, (LDPE 300E, and LDPE PG 7004 , and blends thereof, LDPE 6201, and XU 60021.24 are used to generate the data. The formulations used in creating the Table are shown below.
[0000]
Resin
Foam
Thick-
Density
Density
ness
Cross-
Example
Resin A/B
(kg/m 3 )
(kg/m 3 )
(mm)
linked
1
XU 60021.24*
0.922
33
10
No
2
90/10 (LDPE 300E/
0.923
45
10
No
LDPE PG7004)
3
70/30 (LDPE 300E/
0.923
64
10
No
LDPE PG7004)
4
LDPE 620I
0.923
144
51
No
[0000]
TABLE 1
Resin A
Resin B
Density
Density
(g/cm 3)
(g/cm 3 )
Foam
Polymer
(ASTM
I 2
Polymer
(ASTM
I 2
Density
Thickness
Example
(wt. %)
Type
D792)
(g/10 min)
(wt. %)
Type
D792)
(g/10 min)
(kg/m 3 )
(mm)
Crosslinked
1
100
LDPE
0.922
3.3
—
—
—
—
33
10
No
2
90
LDPE
0.9235
0.8
10
LDPE
0.9215
4.1
45
10
No
3
70
LDPE
0.9235
0.8
30
LDPE
0.9215
4.1
64
10
No
4
100
LDPE
0.9239
1.85
—
—
—
—
144
51
No
Comparative Examples.
Foam
Comparative
Density
Thickness
Crosslinked
Example
Designation
(kg/m 3 )
(mm)
(yes/no)
1c
Qycell T-20*
33
10
yes
2c
Qycell T-30*
45
10
yes
3c
Qycell T-40*
64
10
yes
4c
Qycell T-80*
119
11.5
no
‘*’ denotes foam commercially available from Qycell Corporation (Ontario, California, USA)
[0106] Turning to the shock absorption, vertical deformation, and energy restitution, the performance of non-crosslinked polyethylene foams of Table 1, which are commercially available from The Dow Chemical Company, Midland, Mich. was investigated. The results of this investigation are summarized in FIG. 1 . With respect to Table 1, the compressive stress-strain, compressive creep, and compressive stress-strain behavior is analyzed using an Instron Model 5565 Universal Testing Machine (Norwood, Mass.) fitted with compression plates and a 2 kN load cell. When the tests are performed at 65° C., an Instron environmental chamber (Model 3119-405-21) is also used.
[0107] Samples 2.5 to 5 cm wide by 5 cm deep are cut from sheets of the foam. To measure compressive stress-strain behavior, the samples are inserted between the centers of the compressive plates. The thickness direction of the foam is aligned parallel to crosshead movement. A pre-load of 2.5 N was applied at 5 mm/min, and the crosshead position is re-zeroed. The sample is then compressed at 10 mm/min until the load approached the capacity of the load cell. Stress is calculated by dividing the measured compressive force by the product of the width and depth of the foam. Stress is quantified in units of megapascals (MPa). Strain in terms of percent is calculated by dividing the crosshead displacement by the starting thickness of the foam and multiplying by one hundred. Results for the compressive stress-strain behavior tests are illustrated in FIGS. 2 and 2 c (comparative samples).
[0108] To measure the compressive hysteresis behavior, a foam sample is loaded into the Instron in the same manner as above. A pre-load of 2.5N is applied at 5 mm/min, and the crosshead position is re-zeroed. Then the sample is compressed at 10 mm/min until the stress reaches 0.38 MPA, designated as the compression step. Immediately, the crosshead is then reversed until a load of 0.0038 MPa is reached, designated as decompression. Without interruption, the sample is compressed and decompressed for 10 cycles.
[0109] To measure the compressive creep behavior, a foam sample is loaded into the Instron in the same manner as above, except that the environmental chamber is in place and preheated to a temperature of 65° C. The sample is placed in between the compression plates, at 65° C. After allowing the foam sample to equilibrate inside the chamber for one hour, a pre-load of 2.5 N is applied at 5 mm/min, and the crosshead position is re-zeroed. Load is then applied at 0.16 MPa. Crosshead position is then adjusted automatically by the Instron computer, to maintain a stress of 0.16 MPa for 12 hours. Compressive strain versus time is measured, the results of which are presented in FIGS. 3 and 3 c . After 12 hours, the crosshead returns to its starting position. After another two hours, the foam is removed and allowed to cool to ambient conditions (20° C., 50% relative humidity). The foam thickness is then remeasured. The corresponding strain is designated “strain at release, 2 hr.” The compressive creep behavior test results are presented in FIG. 4 .
[0110] To measure the energy absorption behavior of the foams FIFA quality concept methodology as described in the “March 2006 FIFA Quality Concept Requirements for Artificial Turf Surfaces,” the FIFA handbook of test methods and requirements for artificial football turf; which is fully incorporated herein by reference. These foams are tested according to this methodology and it is found that foams having a density of 144 kg/m 3 , as an example, perform acceptably. More detailed test results on shock absorption are provided below. Returning to compressive performance, the below graphs illustrate that the performance of the foam is not compromised by the elimination of crosslinking. In addition, embodiments of the present invention may be useful for any field that may use artificial turf, such as rugby and field hockey.
[0111] FIGS. 3 , 3 c , and 4 illustrate that essentially the same compressive creep performance and subsequent recovery may be achieved despite the elimination of crosslinking.
[0112] Synthetic turf, using embodiments of the present invention, is shown in FIG. 5 . Specifically, a non-crosslinked polythene foam is provided as a shock absorption layer, which may be bonded to a backing. Artificial grass is attached to the backing, and the spaces between the grass may be filled with an infill.
[0113] Embodiments using non-crosslinked polyethylene may be advantageous as non-crosslinked polyethylene is recyclable, and, thus, there are no environmental issues. Embodiments of the polymer foams described herein may also be useful as heavy layers for noise and vibration dampening, among others.
[0114] While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims.
[0115] All priority documents are herein fully incorporated by reference for all jurisdictions in which such incorporation is permitted. Further, all documents cited herein, including testing procedures, are herein fully incorporated by reference for all jurisdictions in which such incorporation is permitted to the extent such disclosure is consistent with the description of the present invention. | A synthetic turf surface including a synthetic grass carpet having a flexible base sheet, and a shock absorbing pad, wherein the shock absorbing pad includes a non-crosslinked polyolefin foam is shown and described. The foam may be recyclable, as it is non-crosslinked. | 4 |
TECHNICAL FIELD
This invention relates to a composition comprising a fluoroaliphatic radical-containing agent and a polymer comprising cyclic carboxylic anhydride groups for imparting water and oil repellency to fibrous substrates and other materials treated therewith. In another aspect, this invention relates to a method of using such composition to treat such substrates and materials, and in another aspect it relates to the so-treated substrates and materials.
BACKGROUND
The treatment of fibrous substrates with fluorochemical compositions to impart water and oil repellency is known; see, for example, Banks, Ed., Organofluorine Chemicals and Their Industrial Applications, Ellis Horwood Ltd., Chichester, England, 1979, pp. 226-234. Such fluorochemical compositions include, for example, fluorochemical guanidines (U.S. Pat. No. 4,540,497), compositions of cationic and non-ionic fluorochemicals (U.S. Pat. No. 4,566,981), compositions containing fluorochemical carboxylic acid and epoxidic cationic resin (U.S. Pat. No. 4,426,466), and fluoroaliphatic alcohols (U.S. Pat. No. 4,468,527).
Additives have been employed to assist in the oil and water repellency of fluorochemical treating agents.
U.S. Pat. No. 4,215,205 discloses combinations of fluorochemical vinyl polymer and carbodiimide in compositions said to impart durable water and oil repellency to textiles. Some of the carbodiimides disclosed contain fluoroaliphatic groups.
U.S. Pat. No. 5,132,028 discloses compositions for imparting water and oil repellency to fabrics such as silk, said compositions containing a fluorochemical-type, water and oil repellent agent, a carbodiimide, and at least one component selected from the group consisting of plasticizer, metal alcoholate or ester, zirconium salt, alkylketene dimer, aziridine, and alkenyl succinic anhydride.
U.S. Pat. No. 3,955,027 discloses an improved process and composition for water and oil proofing textiles which comprises treating a textile with a polymeric fluorocarbon finishing agent and at least one reactive polymer extender having acid or anhydride functionality and curing the treated textile at from 80° C. to 170° C. for 0.1 to 60 min. The reactive polymer extenders are low molecular weight polymers having a molecular weight of less than about 8000.
U.S. Pat. No. 4,070,152 discloses compositions comprising a textile treating resin which is a fluorine-containing polymer and a novel copolymer of a maleic-anhydride copolymer and a fatty acid amine and an amino organo polysiloxane. Said compositions are useful for increasing the water and oil repellency of substrates such as textiles, paper, or leather.
WO 93/01348 discloses aqueous treating compositions for providing water and oil repellency, stain resistance and dry soil resistance which comprise
a) 0.3 to 30% by weight of a water soluble or dispensable fluoroaliphatic radical-containing polyoxyalkylene compound;
b) 0.3 to 30% by weight of an anti-soiling agent, and
c) water. The anti-soiling agent may include i.e., styrene-maleic anhydride copolymers and vinyl acetate-maleic anhydride copolymers.
Although water and oil repellent treating agents are readily available, it is well known that they are expensive. Also, the efficiency in water and/or oil repellency is not always satisfactory. Furthermore, when they are employed for the treatment of textiles, they suffer from the disadvantage that they tend to give the treated textile a hard feeling. In order to overcome this problem, silicone softeners are commonly applied. However silicones are usually not compatible with the fluorochemical treating agent, and therefore, the treated substrates typically will show a decrease in water and oil repellency.
DISCLOSURE OF INVENTION
It is an object of the present invention to provide a water and oil repellency imparting composition which is less expensive and which can give higher water and oil repellency with a simple one step treatment technique. A further object of the invention is the provision of a water and oil repellency imparting composition that shows high compatibility with common silicone softeners, so as to give the treated substrate a soft feeling, while maintaining the oil and water repellency.
These objects could be achieved by a water and oil repellency imparting composition comprising:
(a) a fluoroaliphatic radical-containing agent; and
(b) a polymer comprising cyclic carboxylic anhydride groups,
with the proviso that the composition does not contain water if the fluoroaliphatic radical-containing agent is a water soluble or dispersible polyoxyalkylene compound and the polymer comprising cyclic carboxylic anhydride groups is a styrene-maleic anhydride copolymer or a vinyl acetate-maleic anhydride copolymer.
Applicants have found that a polymer comprising cyclic carboxylic anhydride groups when used together with a fluoroaliphatic radical-containing agent significantly increases the water and oil repellency imparting effect of the latter. It was also found that a significantly smaller amount of fluoroaliphatic radical-containing agent is required for imparting oil and water repellency to the treated substrate if a polymer comprising cyclic carboxylic anhydride groups is additionally used, whereas larger amounts are required when the fluoroaliphatic radical-containing agent is used alone. It was further found that the polymer comprising cyclic carboxylic anhydride groups when used together with a fluoroaliphatic radical-containing agent increases the compatibility of the latter with commonly used silicone softeners, hence treated substrates have a soft feeling while at the same time the high oil and water repellency is retained.
Briefly, in one aspect the present invention provides a water and oil repellency imparting composition for fibrous and other substrates, said composition comprising a fluorochemical-type, water and oil repellent agent (such as a fluoroaliphatic radical-containing polyacrylate or polyurethane) and a polymer comprising cyclic carboxylic anhydride groups. The composition can further optionally comprise other additives such as, e.g., a softener and/or a plasticizer. The composition can be applied, e.g., to a fibrous substrate by contacting the substrate with the composition, for example, by immersing it in a bath of the composition or by spraying the composition onto the substrate. The treated substrate is then dried to remove the solvent therefrom.
The composition of this invention imparts desirable water and oil repellency to the substrates treated therewith without adversely affecting other desirable properties of the substrate, such as soft hand (or feeling). The composition of the present invention can be used for providing water and oil repellency to fibrous substrates such as textiles, papers, non-woven articles or leather or to other substrates such as plastics, wood, metals, glass, stone and concrete.
DETAILED DESCRIPTION
An important feature of compositions of the present invention is that any of the known fluoroaliphatic radical-containing agents useful for the treatment of fabrics to obtain repellency of water and oily and aqueous stains can be used. Fluoroaliphatic radical-containing agents include condensation polymers such as polyesters, polyamides or polyepoxides and vinyl polymers such as acrylates, methacrylates or polyvinyl ethers. Such known agents include, for example, those described in U.S. Pat. Nos. 3,546,187; 3,544,537; 3,470,124; 3,445,491; 3,341,497 and U.S. Pat. No. 3,420,697. Further examples of such fluoroaliphatic radical-containing water and oil repellency imparting agents include those formed by the reaction of perfluoroaliphatic thioglycols with diisocyanates to provide perfluoroaliphatic group-bearing polyurethanes. These products are normally applied as aqueous dispersions for fiber treatment. Such reaction products are described, for example, in U.S. Pat. No. 4,054,592. Another group of compounds which can be used are fluoroaliphatic radical-containing N-methylolcondensation products. These compounds are described in U.S. Pat. No. 4,477,498. Further examples include fluoroaliphatic radical-containing polycarbodiimides which can be obtained by, for example, reaction of perfluoroaliphatic sulfonamido alkanols with polyisocyanates in the presence of suitable catalysts.
The fluorochemical component is preferably a copolymer of one or more fluoroaliphatic radical-containing acrylate or methacrylate monomers and one or more fluorine-free (or hydrocarbon) terminally ethylenically-unsaturated comonomers. Classes of the fluorochemical monomer can be represented by the formulas:
R.sub.f R.sup.1 OCOC(R.sup.2)═CH.sub.2
and
R.sub.f SO.sub.2 N(R.sup.3)R.sup.4 OCOC(R.sup.2)═CH.sub.2
where
R f is a fluoroaliphatic radical;
R 1 is an alkylene with, for example, 1 to 10 carbon atoms, e.g. methylene or ethylene, or is --CH 2 CH(OR)CH 2 --, where R is hydrogen or --COCH 3;
R 2 is hydrogen or methyl;
R 3 is hydrogen or an alkyl with, for example, 1 to 10 carbon atoms, e.g. methyl or ethyl; and
R 4 is an alkylene with, for example, 1 to 10 carbon atoms, e.g. methylene or ethylene.
The fluoroaliphatic radical, called Rf for brevity, is a fluorinated, stable, inert, preferably saturated, non-polar, monovalent aliphatic radical. It can be straight chain, branched chain, or cyclic or combinations thereof. It can contain heteroatoms, bonded only to carbon atoms, such as oxygen, divalent or hexavalent sulfur, or nitrogen. R r is preferably a fully-fluorinated radical, but hydrogen or chlorine atoms can be present as substituents if not more than one atom of either is present for every two carbon atoms. The R f radical has at least 3 carbon atoms, preferably 3 to 14 carbon atoms, and preferably contains about 40% to about 78% fluorine by weight, more preferably about 50% to about 78% fluorine by weight. The terminal portion of the Rf radical is a perfluorinated moiety, which will preferably contain at least 7 fluorine atoms, e.g., CF 3 CF 2 CF 2 --, (CF 3 ) 2 CF--, F 5 SCF 2 --. The preferred Rf radicals are fully or substantially fluorinated and are preferably those perfluorinated aliphatic radicals of the formula C n F 2n+1 -- where n is 3 to 14.
Representative examples of fluorochemical monomers are: ##STR1## Preferred co-monomers which can be copolymerized with the above-described fluoroaliphatic radical-containing monomers are not hydrophilic and include those selected from the group consisting of octadecylmethacrylate, 1,4-butanediol diacrylate, laurylmethacrylate, butylacrylate, N-methylolacrylamide, isobutylmethacrylate, vinylchloride and vinylidene chloride.
The relative weight ratio of the fluoroaliphatic monomer(s) to the hydrocarbon co-monomer(s) can vary as is known in the art, and generally the weight ratio of them will be 50-95:50-5.
The polymers comprising cyclic carboxylic anhydride groups which are used together with the fluoroaliphatic radical-containing agent include polymers wherein the cyclic carboxylic anhydride groups are integrated into the polymer chain as well as polymers wherein these groups are present as pendant cyclic carboxylic anhydride groups. The former include copolymers of a compound having a terminal ethylenically unsaturated bond and of a cyclic carboxylic anhydride having an ethylenically unsaturated bond whereas the latter include polymers and copolymers of ethylenically unsaturated compounds carrying the cyclic carboxylic anhydride groups as groups pending at the main polymer chain.
Suitable copolymers of a compound having a terminal ethylenically unsaturated bond and a cyclic carboxylic anhydride having an ethylenically unsaturated bond useful in the composition of this invention are described, for example, in U.S. Pat. No. 4,240,916 and U.S. Pat. No. 4,358,573. The cyclic carboxylic anhydride can be an alkyl or aryl substituted or unsubstituted cyclic carboxylic anhydride wherein the alkyl groups contain preferably up to 6 carbon atoms each and the cyclic group contains preferably 4 to 15 carbon atoms, such as maleic or itaconic anhydride. Preferred is maleic anhydride. The compound having a terminal ethylenically unsaturated bond is preferably a 1-alkene, styrene, α methylstyrene, a (meth)acrylic acid derivative, such as an acrylic or methacrylic acid ester, or a vinylether. Such monomers can be used alone or as mixtures. The cyclic carboxylic anhydride can be used in an amount of about 10-70, preferably about 35-70 mol percent. More preferably 45-60 mol percent of ethylenically unsaturated cyclic anhydride is copolymerized with 40-55 mol percent of at least one C 2 to C 30 aliphatic 1-alkene to produce a copolymer such as, e.g., a maleic anhydride/octadecene copolymer, maleic anhydride/decene copolymer, and maleic anhydride/tetradecene copolymer. It is also preferred to copolymerize 45-60 mol percent of a cyclic carboxylic anhydride with 40-50 mol percent of a vinylether of preferably less than 30 carbon atoms to produce a copolymer such as, e.g. a maleic anhydride/octadecyl vinylether copolymer or maleic anhydride/methylvinylether copolymer. It is further preferred to copolymerize 45-60 mole percent of a cyclic carboxylic anhydride with 40-55 mol percent styrene to produce, e.g. a maleic anhydride/styrene copolymer.
The copolymers of a compound having a terminal ethylenically unsaturated bond and a cyclic carboxylic anhydride having an ethylenically unsaturated bond preferably used in the invention are composed of subunits of the following formula (I): ##STR2## wherein the residues R 1 and R 2 may be both hydrogen or one of them is hydrogen and the other is an aliphatic or aromatic group of not more than 30 carbon atoms which may contain up to 5 heteroatoms, R 3 and R 4 are independently hydrogen or methyl, n is an integer of 50 to 1000 and m is an integer of at least 1, which value depends on the molar ratios of the monomers used.
R 1 or R 2 is preferably hydrogen, an alkyl group, an unsubstituted or C 1 -C 5 alkyl substituted phenyl group, an ether group, or a carboxylic ester group. If R 1 or R 2 is an alkyl group, it contains preferably up to about 28 carbon atoms, more preferably up to 22 carbon atoms. If R 1 or R 2 is an ether group or a carboxylic ester group, it contains preferably not more than 30 carbon atoms.
n is preferably an integer from 50 to 750, and m is preferably at least 1.
The residues R 1 and R 2 need not necessarily all be the same.
The most preferred copolymers are composed of subunits of the following formulae: ##STR3## wherein R 5 is hydrogen or alkyl having up to 30 carbon atoms, R 6 is alkyl with up to 30 carbon atoms and n is as defined above, the dashed line indicates that R 5 and OR 6 may be linked to either of the two carbon atoms while the other carries a second hydrogen atom.
Suitable polymers having pendant cyclic carboxylic anhydride groups include polyolefins and poly(meth)acrylic acid derivatives such as esters having such groups pendant at the main polymer chain. Specific examples are copolymers of octadecylmethacrylate (ODMA) with allylmethacrylate (AMA) grafted with maleic anhydride, or polybutadiene polymers grafted with maleic anhydride.
The ratio of fluoroaliphatic radical-containing agent to polymer comprising cyclic carboxylic anhydride groups is preferably between 1:0.02 and 1:3, more preferably between 1:0.05 and 1:1.5 by weight.
The composition of the present invention may further comprise other additives usually employed in oil and water repellency imparting compositions, such as softeners, e.g., silicone softening agents, and/or plasticizers. The softening agent will increase the soft feeling of the treated substrate. Suitable silicone softening agents include those selected from the group consisting of polydimethylsiloxanes, and polyhydroxymethylsiloxanes. If used, the softening agent is present in an amount between 5% and 300% by weight, preferably between 15% and 200% by weight, based on the fluoroaliphatic radical-containing agent.
Suitable plasticizers include aliphatic or aromatic esters, such as dioctyladipate, dioctylazelate, ditridecyladipate, di(2-ethylhexyl)azelate, di(2-ethylhexyl)maleate, diethylhexylsebacate, butylbenzylphtalate, dioctylphtalate, dibutylphtalate, diisodecylphtalate, ditridecylphtalate, and diisononylphtalate; polyester type plasticizers such as Priplast plasticizers (available from Unichema Chemie GmbH, Emmerich, GERMANY) paraffins and substituted paraffins, such as Chlorparaffins (available from Hus AG, Marl, GERMANY) epoxy type plasticizers, such as Rheoplast plasticizers (available from Ciba-Geigy AG, Basel, SWITZERLAND). If used, the plasticizer is present in an amount of between 10 and 200%, preferably between 20 and 100% by weight of the fluoroaliphatic radical-containing agent.
For application, the water and oil repellency imparting composition can be used in solvent solution, emulsion and aerosol forms. Preferably, the composition is used in solvent solution form.
Suitable solvents are those that are capable of solubilizing the fluoroaliphatic radical-containing agent, the polymer comprising cyclic carboxylic anhydride groups and the optional silicone softener and plasticizer. Suitable solvents include chlorinated hydrocarbons, isoparaffinic hydrocarbons, alcohols, esters, ketones and mixtures thereof. Usually, the solvent solutions will contain 0.1 to 10% or even up to 50% by weight solids.
Water is not used as a solvent for the water and oil repellency imparting composition of the present invention if the fluoroaliphatic radical-containing agent is a water soluble or dispersible polyoxyalkylene compound and the polymer comprising cyclic carboxylic anhydride groups is a styrene-maleic anhydride copolymer or a vinyl acetate-maleic anhydride copolymer. As the presence of water in solutions of the compositions of the invention may cause ring opening of the cyclic anhydride which will impair the performance properties of the cyclic anhydride copolymer, it is generally preferred beyond the above restriction that solutions of the compositions of the invention are substantially water free. This means that solutions of the composition of the present invention preferably do not contain more than 5% by weight, more preferably not more than 1% by weight, and still more preferably not more than 0.5% by weight of water, based on the total weight of the composition. Most preferably the compositions of the invention and their solutions do not contain any water.
The amount of the composition applied to a substrate in accordance with this invention is chosen so that sufficiently high or desirable water and oil repellencies are imparted to the substrate surface, said amount usually being such that 0.01% to 5% by weight, preferably 0.05 to 2% by weight, based on the weight of the substrate, of fluoroaliphatic radical-containing agent and polymer comprising cyclic carboxylic anhydride groups is present on the treated substrate. The amount which is sufficient to impart desired repellency can be determined empirically and can be increased as necessary or desired.
The treatment of fibrous substrates using the water and oil repellency imparting composition of the present invention is carried out by using well-known methods including dipping, spraying, padding, knife coating, and roll coating. Drying of the substrate is done at 120° C. or below, including room temperature, e.g. about 20° C. with optionally heat-treating the textile products in the same manner as in conventional textile processing methods.
The substrates treated by the water and oil repellency imparting composition of this invention are not especially limited and include, e.g., textile fabrics, fibers, nonwovens, leather, paper, plastic, wood, metal, glass, concrete and stone.
Respective data of water and oil repellency shown in the Examples and Comparative Examples are based on the following methods of measurement and evaluation criteria:
Spray Rating
The spray rating (SR) of a treated substrate is a value indicative of the dynamic repellency of the treated substrate to water that impinges on the treated substrate, such as encountered by apparel in a rain storm. The rating is measured by Standard Test Number 22, published in the 1977 Technical Manual and Yearbook of the American Association of Textile Chemists and Colorists (AATCC), and is expressed in terms of the "spray rating" of the tested substrate. The spray rating is obtained by spraying water on the substrate and is measured using a 0 to 100 scale where 100 is the highest possible rating.
Oil Repellency
The oil repellency (OR) of a treated substrate is measured by the American Association of Textile Chemists and Colorists (AATCC) Standard Test Method No. 118-1983, which test is based on the resistance of treated substrate to penetration by oils of varying surface tensions. Treated substrates resistant only to Nujol®, mineral oil (the least penetrating of the test oils) are given a rating of 1, whereas treated substrates resistant to heptane (the most penetrating of the test oils) are given a rating of 8. Other intermediate values are determined by use of other pure oils or mixtures of oils, as shown in the following table.
______________________________________Standard Test LiquidsAATCC Oil RepellencyRating Number Composition______________________________________1 Nujol ®2 Nujol ®/n-hexadecane 65/353 n-Hexadecane4 n-Tetradecane5 n-Dodecane6 n-Decane7 n-Octane8 n-Heptane______________________________________
Abbreviations:
The following abbreviations and trade names are used in the examples:
______________________________________PA-18: 1:1 Copolymer of 1-octadecene with maleic anhydride having a molecular weight of about 30000 to 50000, available from Chevron Chemical Company, Geneve, SWITZERLANDMA: maleic anhydrideODMA: octadecylmethacrylateAMA: allylmethacrylateODVE: octadecyl vinyletherGANTREZ AN119: Copolymers of polymethyl vinyletherGANTREZ AN169: with maleic anhydride; MN = 20000GANTREZ AN179: (GANTREZ AN119), Mn = 67000 (GANTREZ AN169) and Mn = 80000 (GANTREZ AN179), available from GAF chemical Corp., Wayne N.J., U.S.A.SMA 3000A: Styrene-maleic anhydride copolymer, available from Atochem S.A., Paris, FRANCEBaysilan Ol M3 Polydimethylsiloxane,(Bay Ol M3): available from Bayer AG., Leverkusen, GERMANYLithene LX16-10MA: Liquid Polymers of ButadieneLithene chemically modified byN4-5000-10MA: 10 weight % MA (LX16-10MA and N4-Lithene PM25MA: 5000-10MA) or 25 weight % MA (PM- 25-MA), available from Revertex, Harlow, U.K.SH8011: A 50% solution in mineral spirits of polydimethylsiloxane, polyhydroxymethylsiloxane and Zn(BF.sub.4).sub.2 available from Toray Industries Inc., Tokyo, JAPANWacker CT 51L A 25% solution in toluene of a(Wa CT 51L): high molecular weight silicone, available from WackerChemie GmBH, Munich, GERMANYWPU: Wet pick upSOF: Solids on fibreMIBK: Methyl isobutyl ketoneDOZ: Dioctylazelate______________________________________
EXAMPLE
The following examples are intended to be illustrative and should not be construed as limiting the invention in any way. All parts, ratios, percentages, etc. in the examples and the rest of the specification, are by weight unless otherwise noted.
Fluoroaliphatic radical-containing agents
The fluoroaliphatic radical-containing agents used in the examples of the present invention are commercially available from 3M:
FX-3530 is a fluoroaliphatic radical-containing polymethacrylate, sold as a 25% solution of fluoropolymer in ethylacetate/heptane.
FX-3532 is a fluoroaliphatic radical-containing polyurethane, sold as a 40% solution of fluoropolymer in ethylacetate.
FX-3534 is a fluoroaliphatic radical-containing polymethacrylate, sold as a 30%; solution of fluoropolymer in methylethylketone.
______________________________________Commercially available substrates______________________________________Pes/Co Utex: Grey polyester/cotton 65/35, style No. 2681, obtained through Utexbel N.V., Ghent, BELGIUM.100% Cotton: Bleached, mercerized cotton poplin, style No. 407, purchased from Testfabrics, Inc., U.S.A.100% Silk: YIS Colour fastness test substrate.______________________________________
Synthesis of polymers comprising cyclic carboxylic anhydride groups in the polymer main chain.
Several polymers comprising cyclic carboxylic anhydride groups as given in Table 1 have been prepared according to the general method as described below (as cyclic carboxylic anhydride, maleic anhydride was used):
In a three necked flask equipped with a mechanical stirrer, a nitrogen inlet and a condenser were placed a compound having a terminal ethylenically unsaturated bond and maleic anhydride in a solvent at 50% solids (30% in case of the (meth) acrylic esters). The solvent used is listed in Table 1. To this mixture was added 2% by weight of azobisisobutyronitrile (AIBN), based on monomer weight (0.3% in case of the (meth) acrylic esters, plus 0.3% n-octylmercaptan). The reaction mixture was purged with nitrogen and reacted at 72° C. under nitrogen during 16 hours (20 hours in case of the (meth)acrylic esters). In all cases clear viscous solutions were obtained.
TABLE 1______________________________________Preparation of polymers comprisingcyclic carboxylic anhydride groupsin the polymer main chainCompound Mol Ratio MaleicUsed Having a Anhydride/Compoundin Terminal Having a TerminalEx. Ethylenically EthylenicallyNo. Unsaturated Bond Unsaturated Bond Solvent______________________________________33 1-Octadecyl 50:50 Toluenevinylether34 1-Hexadecene 50:50 Toluene35 1-Decene 50:50 Toluene36 1-Tetradecene 50:50 Toluene37 1-Hexene 50:50 MIBKC-13 Octadecyl- 0:100 Ethylacetatemethacrylate71 Octadecyl 45:55 EthylacetatemethacrylateC-14 Butylmethacrylate 0:100 Ethylacetate72 Butylmethacrylate 26:74 Ethylacetate73 Butylmethacrylate 49:51 Ethylacetate______________________________________
Molecular weight analysis of the polymers comprising cyclic carboxylic anhydride groups in the polymer main chain.
The GPC (gel phase chromatography) analysis has been done using a Perkin Elmer Series 400 pump autosampler from Polymer Laboratories. The columns (30 cm-0.46 cm) are packed with PL gel (polystyrene crosslinked with divinylbenzene) with a particle size of 10 micron. The eluent used is THF (tetrahydrofuran). Flow rate: 1 ml/min. The calibration is done with polystyrene standards having molecular weights between 1200 and 2,950,000. The flow rate marker is toluene. The molecular weight is calculated with a PL GPC data station version 3.0. Detection is done with a PE LC25 refractive index detector. The results of the analysis are given in Table 2 below: Mw is the weight average molecular weight; Mp is the peak molecular weight; Mn is the number average molecular weight and p is the polydispersity (Mw/Mn).
TABLE 2______________________________________Molecular weight analysisCopolymer of MaleicAnhydride with Mn Mw Mp p______________________________________1-octadecyl 131 832 145 622vinylether1-Hexadecene 6 017 11 324 9 228 1.91-Decene 5 400 12 427 10 975 2.31-Tetradecene 7 092 11 924 9 890 1.71-Hexene 7 759 14 390 11 227 1.9______________________________________
Synthesis of polymers comprising pendant cyclic carboxylic anhydride groups
(Meth)acrylate polymers comprising pendant cyclic carboxylic anhydride groups have been prepared according to the general method as described below:
In three necked flasks equipped with a mechanical stirrer, a nitrogen inlet and a condenser were placed octadecyl methacrylate and allylmethacrylate in a ratio of 90/10 and 80/20, respectively. The monomers were diluted with butylacetate to 40%. To these mixtures was added 0.75% by weight of initiator azobisisobutyronitrile (AIBN), and 1% chain transfer agent n-octylmercaptan (based on monomer weight). The reaction mixtures were purged with nitrogen and reacted at 72° C. under nitrogen during 16 hours.
In a second step, maleic anhydride was grafted to the methacrylic polymers, according to the following method:
To the allyl (meth)acrylate copolymers prepared as described above, maleic anhydride was added in an amount to provide a 1/1 molar ratio of the maleic anhydride to the allyl(meth)acrylate. Additional 1% AIBN based on the total solids was added and the mixtures were further diluted with butylacetate to 30% solids. The mixtures were purged with nitrogen and further reacted at 72° C. for another 16 hours.
The copolymers ODMA/AMA 90/10 and 80/20, grafted with MA are evaluated in examples 74 and 75, respectively. The copolymers ODMA/AMA 90/10 and 80/20 that were not grafted with MA are used in comparative examples C-16 and C-17 (see also table 13).
Examples 1 to 6 and Comparative Examples C-1 to C-3
In examples 1 to 6, blends were made of FX-3530, FX-3532 or FX-3534 with PA-18 in MIBK in different ratios as given in Table 3. The blends were applied to Pes/Co Utex fabric by solvent padding, at 100% WPU. The fabrics were dried at 70° C. for 30 minutes. Alternatively, the fabrics were additionally ironed at 150° C. for 5 sec. Comparative examples C-1 to C-3 were made without the addition of PA-18. In all cases, the tests were done in a way to give a concentration of the treating solution of 0.3% solids on fibre. The results are given in Table 3.
TABLE 3______________________________________Performance properties of Pes/co Utexsubstrate treated with fluoroaliphaticradical-containing agent-PA-18 mixturesFluoroaliphatic Dried +Ex. Radical-Containing Ratio* Dried IronedNo. Agent (FC) FC/PA-18 OR SR OR SR______________________________________1 FX-3530 90/10 4 100 4 1002 FX-3530 80/20 4 100 4 1003 FX-3532 90/10 4 70 4 704 FX-3532 80/20 4 70 4 705 FX-3534 90/10 4 100 4 1006 FX-3534 80/20 4 100 4 100C-1 FX-3530 100/0 4 70 4 80C-2 FX-3532 100/0 4 50 5 50C-3 FX-3534 100/0 4 90 4 90______________________________________ Note: Ratio *: weight % of solid material
The results of the experiments shown in this table indicate that in all cases an improvement of the spray rating is observed, even when small amounts (10%) of the fluoroaliphatic radical-containing agent are replaced by PA-18. The oil repellency rating remains at the same high level.
Examples 7, 8 and Comparative Example C-4
In example 7, a treatment solution containing FX3530, PA-18 and dioctylazelate plasticizer in MIBK was used. Example 8 was carried out the same way, except that SMA 3000A was used instead of PA-18.
Comparative example C-4 was carried out in the same way but no polymer comprising cyclic carboxylic anhydride groups was used.
The treatment solutions were applied to different substrates by solvent padding, at 100% WPU. The treated fabrics were dried at room temperature, eventually followed by a heat treatment for 15 sec at 150° C. (ironed). This method provided the fabrics with 0.3% SOF FX-3530, 0.06% SOF polymer comprising cyclic carboxylic anhydride groups (except for C4) and 0.15% SOF plasticizer. The results are given in Table 4.
TABLE 4__________________________________________________________________________Performance properties of substratestreated with mixtures of fluoroaliphaticradical-containing agent and polymercomprising cyclic carboxylic anhydride groups.PolymerComprisingCyclic Carboxylic 100% Cotton SilkEx. Anhydride Air Dry Ironed Air Dry IronedNo. Groups OR SR OR SR OR SR OR SR__________________________________________________________________________7 PA-18 4 100 3 100 4 100 4 958 SMA 3000A 4 80 2 80 3 90 4 85C-4 / 3 60 1 70 4 80 4 80__________________________________________________________________________
Again, it is shown that the tested treatment solutions containing a polymer comprising cyclic carboxylic anhydride groups give improved oil and water repellency as compared to the fluorochemical treatment solution without such polymers added. Both SR and OR values indicate that it is not required to give the fabric a heat curing treatment after application.
Example 9 and Comparative Example C-5
The same kind of experiment as outlined for Example 4 was repeated but the treatment solutions were made in perchloroethylene for dry clean applications and no additional plasticizer was used. As substrate, Pes/Co Utex was chosen and the composition was applied by solvent padding to give a total of 0.1% SOF (0.08% SOF FX-3530 and 0.02% SOF PA-18 for example 9 and 0.1% SOF FX-3530 for C-5) after drying, which is a typical add-on for dry clean applications. The treated substrates have been dried at 70° C. for 30 min, eventually followed by ironing at 100° C. for 5 sec. Comparative example C-5 was made without PA-18. The results are given in Table 5.
TABLE 5______________________________________Performance properties of substrates treated withFX-3530 with and without PA-18, respectively. Dried Dried + IronedEx. No. OR SR OR SR______________________________________9 1 80 1 100C-5 0 50(W) 0 50(W)______________________________________ Note: (W): Reverse side is wet
The sample with the PA-18 reaches the minimum requirement for dry clean application, being an oil repellency rating of 1 and a spray rating of 100 after ironing.
Examples 10 to 19 and Comparative Example C-6
In examples 10 to 13, FX-3530 was gradually replaced by PAl8, so as to obtain a constant level of 0.3% solids on fibre after drying. In examples 14 to 19, the level of FX-3530 was kept constant at 0.3% SOF and the amount of PA-18 was gradually increased. Comparative Example C-6 was made without the addition of PA-18. All treatment solutions in MIBK of examples 10 to 19 and Comparative Example C-6 were applied to Pes/Co Utex fabric. After treatment, the fabric was dried at 70° C. for 30 min, eventually followed by heat treatment at 150° C. for 5 sec (ironed). The results of oil and water repellency test are given in Table 6.
TABLE 6______________________________________Performance properties of Pes/Co Utex substratetreated with FX-3530 - PA-18 in different ratios Dried +Ex. Dried IronedNo. % SOF FX-3530 PA-18 OR SR OR SR______________________________________10 0.24 0.06 4 100 4 10011 0.18 0.12 3 100 3 10012 0.12 0.18 2 100 2 10013 0.06 0.24 1 90 1 9014 0.3 0.03 4 100 3 10015 0.3 0.06 4 100 3 10016 0.3 0.12 4 100 3 10017 0.3 0.18 4 100 3 10018 0.3 0.3 4 100 4 10019 0.3 0.6 5 100 4 100C-6 0.3 0 4 80 3 80______________________________________
The results indicate that even a small amount of PA-18 gives a significant improvement of the spray rating. The performance of the treated samples remain high, even when about half of the amount of FX-3530 is replaced by PA-18. The addition of higher amounts (higher than 0.3% SOF) of PA-18 to the fluoroaliphatic radical-containing agent does not increase the performance of the treated samples substantially, but it does not deteriorate the performance either.
Examples 20 to 22 and comparative Examples C-7 to C-9
In the examples 20 to 22 various silicone softening agents were evaluated in combination with the water and oil repellency imparting compositions of the present invention, to improve the softness of the treated fabric. Treatment solutions were applied to the fabrics by solvent padding, to give a concentration of 0.3% SOF of silicone softener, 0.3 SOF of FX-3530, 0.15% SOF Dioctylazelate and 0.06%; SOF of PA-18. Comparative examples C-7 to C-9 were made without addition of PA-18.
All treatment solutions (in MIBK) were applied to the fabric by solvent padding. The treated fabrics are dried at room temperature (examples 20 and 21 and comparative examples C-7 and C-8) or at 70° C. for 30 min (example 22 and comparative example C-9) eventually followed by heat cure at 150° C. for 15 sec (Ironed). The results are given in Table 7.
TABLE 7__________________________________________________________________________Performance properties of substrates treatedwith mixtures of FX-3530, PA-18 and silicone softener 100% Cotton Pes/co UtexEx. Silicone PA-18 Dried Ironed Dried IronedNo. type SOF OR SR OR SR OR SR OR SR__________________________________________________________________________20 SH8011 0.3 6 100 3 100 5 100 3 100C-7 SH8011 0 3 90 3 90 5 100 3 10021 BayOl M3 0.3 2 100 2 100 1 100 2 100C-8 BayOl M2 0 4 70 4 70 4 60 4 6022 Wa CT51L 0.3 5 100 5 100C-9 Wa CT51L 0 5 70 5 70__________________________________________________________________________ Note: the samples containing Wacker CT 51L contain 0.13% SOF dioctylazelate.
In most cases, the addition of PA-18 increases the spray rating of the treated fabric. Except for the Baysilan 01 M3, the oil rating remains about the same.
Examples 23 to 29 and Comparative Example C-10
In examples 23 to 29, different amounts of PA-18 were used in combination with FX-3530 (0.3% SOF), silicone softener SH8011 (0.3% SOF) and Dioctylazelate plasticizer (0.15 SOF). The treatment solutions were applied to 100% cotton by solvent padding (MIBK). The treated substrates were dried at room temperature and conditioned overnight before testing. Comparative example C-10 was made without PA-18. The results of oil repellency and spray rating are given in Table 8.
TABLE 8______________________________________Performance properties of 100%cotton treated with FX-3530/PA-18 PA-18, % of 100% FX-3530 CottonEx. No. PA-18, % SOF Solids OR SR______________________________________23 0.006 2 5 9024 0.015 5 5 9525 0.03 10 5 10026 0.06 20 5 10027 0.15 50 5 10028 0.3 100 5 10029 0.6 200 5 100C-10 0.0 0 4 90______________________________________
The results indicate that even a very small amount of PA-18 causes already an increase in oil repellency. It is also clear that there is no real limit on the addition of PA-18. Preferably a minimum amount of PA-18 of 5% of the FX-3530 solids is used.
Examples 30 to 37 and Comparative Example C-11
In examples 30 to 37 blends were made of FX-3530 with different polymers comprising cyclic carboxylic anhydride groups in MIBK in a ratio of 80/20. The blends were applied to Pes/Co Utex fabric by solvent padding, at 100% WPU. The fabrics were dried at 65° C. for 30 minutes, eventually also ironed at 150° C. for 5 sec. Comparative example C-11 was made without the addition of such a polymer. The test was done in a way to give a concentration of the treating composition of 0.3% solids on fibre. The results of testing are given in Table 9.
TABLE 9______________________________________Performance properties of Pes/Co Utexsubstrate treated with mixtures offluoroaliphatic radical containingagent and a polymer comprising cycliccarboxylic anhydride groups Polymer comprising Dried +Ex. Cyclic Carboxylic Dried IronedNo. Anhydride Groups OR SR OR SR______________________________________30 Gantrez AN119 2 100 2 10031 Gantrez AN169 2 100 2 10032 Gantrez AN179 2 100 2 10033 ODVE/MA 3 90 2 10034 Hexadecene/MA 3 100 3 10035 Decene/MA 2 100 2 10036 Tetradecene/MA 3 100 3 10037 Hexene/MA 3 100 2 100C-11 / 3 80 3 80______________________________________
Although 20% of the fluoroaliphatic radical-containing agent is replaced by a polymer comprising cyclic carboxylic anhydride groups, very little influence is seen on the oil repellency of the treated sample. Moreover, the water repellency is increased.
Examples 38-, to 57
In examples 38 to 57 different plasticizers were evaluated in the water and oil repellency imparting composition of the present invention. In all examples, a solution in MIBK of FX-3530 (0.3% SOF), silicone softener SH8011 (0.3% SOF), PA-18 (0.06% SOF) and plasticizer (0.15% SOF) was used to treat a 100% cotton substrate. The treated substrate was dried at room temperature and conditioned overnight before testing. The results are given in Table 10.
TABLE 10______________________________________Performance properties of 100%cotton substrate treated withfluoroaliphatic radical-containing agent,polymer comprising cyclic carboxylic anhydridegroups, silicone softener and plasticizer. 100% CottonEx. No. Plasticizer Type OR SR______________________________________38 Chlorparaffin 45 G 5 10039 Chlorparaffin 40 N 5 9540 Chlorparaffin 52 G 5 9541 Chlorparaffin 40 G 5 10042 Priplast 3124 6 9543 Priplast 3155 5 9044 Priplast 3114 5 10045 Priplast 3126 5 10046 Priplast 3157 5 10047 Priplast 3159 5 10048 Ditridecyladipate 6 10049 Dioctylazelate 6 10050 Diethylhexylsebacate 6 10051 Diisodecylphtalate 6 10052 Dibutylphtalate 3 10053 Dioctylphtalate 6 10054 Butylbenzylphtalate 6 10055 Ditridecylphtalate 6 10056 Diisononylphtalate 6 10057 Rheoplast 39 6 100______________________________________ Notes: Chlorparaffin: available from Huls Priplast: available from Unichema Rheoplast 39: epoxytype plasticizer from CibaGeigy
The results in this table indicate that the performance of the treated substrate is high, independent of the structure of the added plasticizer.
Examples 58 to 70
In examples 58 to 70 the amount of the plasticizer has been varied. In all cases, solutions in MIBK of FX-3530 (0.3% SOF), PA-18 (0.06% SOF), silicone softener SHBOll (0.3% SOF) and plasticizer (various amounts as given in table 11) were applied to 100% cotton. The plasticizers evaluated were butylbenzylphtalate (BBP) and dioctylazelate (DOZ). The treated substrates were dried at room temperature and conditioned overnight before testing. The results of oil repellency and spray rating are given in Table 11.
TABLE 11______________________________________Performance properties of 100% cottonsubstrate treated with fluoroaliphatic radical-containing agent, polymer comprising cyclic carboxylicanhydride groups, silicone softener and plasticizer PlasticizerEx. Plasticizer % Solids 100% CottonNo. Type SOF of FX-3530 OR SR______________________________________58 / 0 0 1 10059 BBP 0.015 5 1 10060 BBP 0.03 10 1 10061 BBP 0.06 20 2 10062 BBP 0.15 50 4 10063 BBP 0.3 100 5 10064 BBP 0.6 200 5 10065 DOZ 0.015 5 2 10066 DOZ 0.03 10 2 10067 DOZ 0.06 20 3 10068 DOZ 0.15 50 5 10069 DOZ 0.3 100 5 10070 DOZ 0.6 200 4 100______________________________________
The results in this table indicate that it is preferable to add a plasticizer to the treatment solution of the present invention when a silicone softener is also used. The plasticizer can be added in various amounts, but preferably it is added at a minimum of 20% of the fluoroaliphatic radical-containing agent solids.
Examples 71 to 73 and Comparative Examples C-12 to C-14
In examples 71 to 73, FX-3530 was gradually replaced by the copolymers of (meth)acrylic acid esters with maleic anhydride as given in Table 1, so as to obtain a constant level of 0.3% solids on fabric after drying. Comparative Example C-12 was made without the addition of such a copolymer. In Comparative Examples C-13 and C-14 a homopolymer of the (meth)acrylic acid ester was used. All treatment solutions in MIBK of Examples 71 to 73 and Comparative Examples C-12 to C-14 were applied to Pes/Co Utex fabric. After treatment the fabric was dried at 70° C. for 30 min, eventually followed by heat treatment at 150° C. for 5 sec (ironed). The results of oil and water repellency tests are given in Table 12.
TABLE 12______________________________________Performance of Pes/Co Utex fabrictreated with FX-3530 and (meth)acrylicacid ester/maleic anhydride copolymers of(meth)acrylic acid ester homopolymers Dried +Ex. FX-3530 Copolymer Dried IronedNo. Solids Solids OR SR OR SR______________________________________C-12 0.3 4 80 3 80C-13 0.24 0.06 4 80 4 8071 0.24 0.06 4 100 4 100C-14 0.24 0.06 4 80 3 10072 0.24 0.06 4 90 3 9073 0.24 0.06 4 100 3 100______________________________________
Examples 74 to 78 and Comparative Examples C-15 to C-17
In examples 74 to 78 blends were made of FX-3530 (0.3% SOF) with polymers comprising pendant cyclic carboxylic anhydrides (0.06% SOF) as given in table 13. Comparative example C-15 was made without the addition of a polymer comprising pendant cyclic anhydrides. In comparative examples C-16 and C-17, methacrylic acid ester copolymers of ODMA/AMA without grafted MA were used. The blends were applied to Pes/Co Utex fabric by solvent padding (MIBK), at 100% WPU. The fabrics were dried at 60° C. for 30 minutes. Alternatively, the fabrics were additionally ironed at 150° C. for 5 sec. The results of the performance of the treated fabrics are given in table 13.
TABLE 13______________________________________Performance properties of Pes/Co Utexsubstrate treated with fluoroaliphatic radical-containing agent (0.3% SOF) and polymer comprisingpendant cyclic carboxylic anhydride groups (0.06% SOF) Pes/Co UtexPolymer comprising Dried +Ex. pendant cyclic Dried IronedNo. carboxylic anhydride OR SR OR SR______________________________________74 (ODMA/AMA 90/10)/MA 5 90 4 10075 (ODMA/AMA 80/20)/MA 5 100 4 10076 Lithene LX-16-10MA 3 100 3 10077 Lithene N4-5000-10MA 3 100 3 10078 Lithene PM-25MA 3 100 4 100C-15 / 4 70 3 70C-16 ODMA/AMA 90/10 5 70 4 70C-17 ODMA/AMA 80/20 4 70 4 70______________________________________
The results in table 13 indicate that the addition of a polymer comprising pendant cyclic carboxylic anhydride groups to the fluoroaliphatic radical-containing agent gives an overall higher performance of the treated fabric. | The invention relates to a water and oil repellency imparting composition which comprises:
(a) a fluoroaliphatic radical-containing agent; and
(b) a polymer comprising cyclic carboxylic anhydride groups.
Additionally, the composition may comprise:
(c) a softener and/or a plasticizer. The composition provides water and oil repellent properties to fibrous and other substrates treated therewith and it shows high compatibility with the commonly used softeners. | 3 |
The invention described herein may be manufactured, used, and licensed by or for the Government of the United States of America for governmental purposes without the payment to me of any royalties thereon.
BACKGROUND AND FIELD OF THE INVENTION
The invention relates to the field of permanent magnet structures, and more particularly to the fabrication of permanent magnet core elements using hot isostatic pressing techniques for densification of the magnetic core materials. The invention is particularly advantageous in the construction of radially oriented magnet elements for use in miniaturized traveling wave tubes (TWTs). The unique method and apparatus according to the invention provides for the complete and leakproof sealing of a permanent magnet core assembly in fabrication process, after the degassification step, but prior to the hot isostatic pressing procedure, without the application of heat to effect the closure, thus insuring the elimination of adverse effects that closure steps involving heating, hot welding, or the like could, and would, most likely produce.
The utilization of permanent magnet structures and devices to replace electromagnetic type yokes in electronic apparatus, cathode ray tubes for instance, has received significant acceptance in the electronics industry. Precision and miniaturization which is attainable with permanent magnet type structures and assemblies is, for the most part, not attainable with the use of electromagnetic structures. Permanent magnets made according to the present invention find particularly advantageous application where the focusing of an electron beam in a given apparatus is a critical factor. Such devices include traveling wave tubes and extended interaction amplifiers which, in turn, find application in microwave/millimeterwave communications, radar, and jamming apparatus for military and national security use.
It has been found through experience in this area that radially oriented cores are most beneficial and frequently essential to the miniaturized periodic permanent magnet stack assemblies used. It has been further found that a preferred means of fabricating these structures is by the hot isostatic pressing technique. This method has been found superior to alternative and somewhat traditional methods of densification of cores such as sintering and the like procedues, where the structure is vulnerable to fracture and sometimes even severe cracking, rendering the product-in-process completely useless. The reasons for this are within the knowledge of artisans practicing the technology; the basic causes being due to extremely high strains introduced upon cooling of the elements which have been heated for the densification sintering and the like steps. Where different materials are used, there is, of course, the further problem of anisotropy in the thermal expansion coefficients of several different materials employed in fabricating or assembling the apparatus. A major disadvantage and problem with hot isostatic pressing techniques, prior to the time of the present invention, has been the effective accomplishment of degassification, and then the effective sealing off of the container being used in the process, without damaging the magnets being made. Heretofore, whenever some sort of heat sealing has been used after the degassification step, the product has been put at risk because of the detrimental effects of such heat.
The technique of fabricating permanent magnet elements through the methods of hot isostatic pressing generally has been known in the art. Traditionally, the steps of permanent magnet fabrication involve the vacuum melting and chill casting of some alloy of magnetic material, followed by a comminution of grinding of the alloy until it is milled and or hydrided to the preselected partical size and morphology for the desired end product.
The particalized material is thereafter disposed in a die press wherein it is isostatically compressed to the required degree of densification.
Traditionally, after the desired degree of densification had been attained, further steps in the manufacturing process including hipping, followed by heat treatment, and/or sintering followed by heat treatment. The cores or individual magnet elements thus produced are then machined to the desired configurations and tested for integrity by means of X-ray diffraction or metallography beam microscopy.
The rings would then be assembled into the desired magnetic elements, impulse magnetized, and measured for magnetometry evaluation or achievement. Radial field evaluations and transverse field distribution measurements are then made, in the nature of quality control checks.
The problems encountered with the prior art technique of manufacturing permanent magnet structures in accordance with the foregoing description were that the end products are less than completely satisfactory in any instance where the heat applied to the material in process after its densification would tend to bring about cracking, spalling, or other forms of magnetically detrimental phenomena to the discs and core pieces which were to be the major elements of the finished magnet.
BRIEF DESCRIPTION OF THE INVENTION
With this then being the state of the art, I conceived and developed my invention with the principle object of providing a method and apparatus for the production of relatively small permanent magnets, using isostatic hot pressing techniques towards the attainment of desired preselected densification qualities to the extent necessary to insure permanent magnetic and structural integrity, and wherein the critical fabrication step of sealing off after degassification is accomplished without the utilization or application of any heat which could detrimentally affect the magnetic and/or structural properties of the finished article.
In general, apparatus according to my invention comprehends a bakeable evacuative container assembly to fabricate a permanent magnet assembly, which comprises, in combination, a core element, a stack of magnetic substance elements disposed contiguously to each other on said core element, isostatically compressed at an elevated temperature to the desired degree of densification, an outer shell element disposed contiguously to the outer peripheral surface of the assembled stack of core elements, an end closure means permanently affixed to the outer shell and in contiguous bearing contact on the end of the stacked elements, a second end closure means arranged and disposed at the other end of the assembly, fixedly attached to the outer shell element and in contiguous contact with the other end of the stacked magnetic elements, with the important additional feature of a vent means provided extending from the second end closure means, this vent means being sealably closeable without the application of heat.
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described in greater detail and with reference to the drawing wherein:
FIG. 1 is an exploded view of the several elements of apparatus according to the invention, arranged longitudinally and shown prior to assembly;
FIG. 2 shows apparatus according to the invention completely assembled and with the vent tube on the second end closure means pinchably closed; and
FIG. 3 shows a completed blank or ingot of magnets made according to the invention, after hot isostatic pressing, with the outer jackset element cut away, but prior to cutting up into discrete magnets.
Referring to FIG. 1, a multiplicity of magnetic substance core elements 13, disc-like in shape and provided with centrally registering holes, are assembled on a ferromagnetic core element 11, a hollow steel pin for instance, formed integrally with an end closure 17, also of stainless steel, and the entire assembly arranged to be disposed interiorly of an outer shell element 15, a thin-wall stainless steel tubing for example. Then separating washers 25 of slighty smaller diameter than the core elements 13 are arranged, one each between each two adjacent core elements 13.
The end closure 17 of stainless steel or the like, is arranged to close one end, the right end as shown in the drawing, of the assembly and this end closure is permanently affixed to the outer shell element 15 by a heliarc welding or the like permanent bonding technique at the completion of the assembly.
An end closure 19 is provided as shown at the left in FIG. 1 of the drawing. The end closure 19 is designed to fit over the end of the thin-wall tube outer shell 15 in a cap-like manner and to provide for the complete enclosure of the hollow pin element 11 and magnetic core elements 13 disposed interiorly of the outer shell. Extending longitudinally from the end closure 19 is a closeable vent tube 21. It has been found advantageous to dispose the vent tube centrally of the end closure element and in substantial alignment with the longitudinal dimension of the permanent magnet assembly.
In accordance with the present invention, the addition of heat after the densification process step is completely eliminated, because the pinchable tube 23 is closed off before the hot isostatic pressing but after degassification of the structure and this, as can be readily appreciated, is done without the application of any further heat such as could detrimentally affect either the brazing connection between the end closure cap 19 and outer shell element 15 or, more importantly, the magnetic integrity of the core element assembly composed of the magnetic substance core elements 13.
EXAMPLE
A working embodiment of the present invention was fabricated according to the following:
A multiplicity of SmCo magnet discs 13 was arranged in registration around a central hollow steel pin 1 formed integrally with an end closure 17 as shown in FIG. 1. Flat washers 25, about 1/32" thick and of diameter about 1/16" less than the disc diameter were interspersed between the disc 13, as shown. The assembled discs 13, pin 11, and end closure 17 were interiorly disposed in a stainless steel thin wall tube approximately 1 7/8" inches long and 3/4" inch diameter. End closure 17, of stainless steel, was heliarc welded to the stainless steel outer shell element 15. In this example, a number 304 stainless steel tube with a 10 mil thick wall was used, and the tube was cut to a length of 1 7/8" inches. Prior to the insertion of the assembled pin, discs, washers and end closure 17 into tube 15, the end closure element 19, made of copper, was affixed to the other end of the assembly with PERMA BRAZE 130 brazing having a melting point of 950° C. After brazing of the closure cap 19 into place, insertion of the rest of the elements, and heliarc welding of the end closure 17 of the tubing 15, the assembly was tested for vacuum leaks.
The bake-out procedure involved holding the assembly at 400° C. (note that this temperature is substantially below the PERMA BRAZE temperature used to affix the end enclosure 19 to the shell) for at least one hour after insertion into the heat zone. At the end of this time, the assembly is removed from the furnace under a vacuum, cooled and cold-welded shut with a pinch-off tool by squeezing the end of the closeable vent tube 21 to form the pinched tube point 23. The use of the copper for end closure 19 permits what amounts to cold welding to effect the final sealing whereas, normal arc welding, requiring an argon or helium atmosphere, could not be tolerated since these gases would diffuse into the open pores of the low density cores and might easily reach a temperature higher than that use to effect the PERMA BRAZE connection of the end cap closure element 19 to the outer shell element 15.
FIG. 3 of the drawing shows a completed magnet blank or ingot with the main portion of the outer shed or tube 15 stripped away. Customarily, blanks of this type are cut up into smaller disc-like elements which are then magnetized and used as desired.
Numerous alternative structures and embodiments, all within the spirit of this invention, will be well within the skills of persons familiar with the art, upon their reading the foregoing disclosure. It is intended, therefore, that the disclosure be viewed as illustrative only and not construed in any limiting sense, it being my intention to define the invention by the appended claims. | A bakeable evacuative fabrication assembly for the production of permanentagnets formed by assembling discrete magnetic elements on a core, enclosing such assembly in a close-fitting container, providing end closures on said container, and providing a one of said end closures with a sealably closeable cold mold vent means. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims priority of German Patent Application No. 10 2006 003 923.8, filed Jan. 26, 2006, which application is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to a coolant distribution device for a wet-running clutch device and comprising several coolant distribution surfaces along which coolant is conveyed outwards in the radial direction. The invention furthermore relates to a wet-running clutch device with friction units on the driving side and the driven side, where the friction units are formed of a plurality of friction partners alternating in layers in the axial direction on the driving side and the driven side, where the friction partners can be pressed against one another in the axial direction to produce a frictional engagement.
SUMMARY OF THE INVENTION
[0003] It is a general object of the invention to increase the service lifetime of a wet-running clutch device, such as is known, for example, from U.S. Pat. No. 4,446,953.
[0004] The object is realized in a coolant distribution device for a wet-running clutch device with several coolant distribution surfaces along which coolant is conveyed outwards in the radial direction by the fact that the coolant distribution surfaces are implemented so that the coolant conveyed outwards in the radial direction has different axial coolant spray-off points and/or coolant spray-off devices. Through the configuration, according to the invention, of the coolant distribution surfaces the coolant can be conveyed in a targeted manner to different axial positions. Thereby, providing different clutch lining elements with coolant in a defined manner is made possible.
[0005] In a preferred embodiment, the coolant distribution device includes coolant distribution surfaces on ramps which, on the outside in the radial direction, have, as seen in the circumferential direction, different slopes. Due to the centrifugal force acting during operation, the coolant is conveyed outwards in the radial direction to the clutch lining elements. Due to the different slope angles of the ramps the coolant sprays off at different axial positions and in different directions at the radially outer edges of the ramps.
[0006] In an additional preferred embodiment, the coolant distribution surfaces are bounded by ribs. At a rotary speed the coolant comes into contact with the ribs, which preferably run helically from the interior outwards, and is thereby affected in its radial acceleration and direction of flight.
[0007] In an additional preferred embodiment, the coolant distribution device comprises a coolant distribution element which essentially has the shape of an annular disk and on which the coolant distribution surfaces are provided. Preferably, the coolant distribution element comprises a plane annular surface on the inside in the radial direction, from which the coolant distribution surfaces extend outwards.
[0008] In an additional preferred embodiment, the coolant distribution device comprises a drive sleeve. The drive sleeve serves preferably to connect the coolant distribution device in the manner of a drive to a coolant pump which is driven via the coolant distribution device.
[0009] In an additional preferred embodiment, the drive sleeve comprises coupling elements. The coupling elements preferably serve to connect the drive sleeve in the manner of a drive to a drive element of a coolant pump, which is driven via the coolant distribution device.
[0010] In an additional preferred embodiment, the coolant distribution device comprises a receiving plate. Preferably, the coolant distribution element is fastened to the receiving plate on the inside in the radial direction.
[0011] In an additional preferred embodiment, the receiving plate comprises coupling elements on the outside in the radial direction. The coupling elements preferably serve to connect the coolant distribution device, in such a manner that it cannot turn, to a clutch part, in particular a lamella carrier, where the clutch part or lamella carrier is in turn driven at the rotary speed of the motor.
[0012] In an additional preferred embodiment, the coolant distribution surfaces have a sharp edge on the outside in the radial direction. Thereby, an uncompromised spraying off of the coolant at the coolant spray-off points is ensured. Preferably, the edge has a radius which is less than 0.5 mm.
[0013] In a wet-running clutch device with friction units on the driving side and the driven side, where the friction units are formed from a plurality of friction partners alternating in layers in the axial direction on the driving side and the driven side, where the friction partners can be pressed against one another in the axial direction to produce a frictional engagement, the above-stated objective is realized by a coolant distribution device described in the introduction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Further advantages, features, and details of the invention follow from the following description, in which various embodiment examples are described in detail with reference to the drawings in which:
[0015] FIG. 1 is a perspective representation of a coolant distribution device according to the invention;
[0016] FIG. 2 is a perspective sectional representation of the coolant distribution device from FIG. 1 ;
[0017] FIG. 3 is a three-part coolant distribution device, as represented in perspective in FIG. 1 , in exploded representation;
[0018] FIG. 4 is a section of a coolant distribution device from FIG. 3 in perspective representation;
[0019] FIG. 5 is a two-part coolant distribution device, as represented in perspective in FIG. 1 , in exploded representation;
[0020] FIG. 6 is a section of a coolant distribution device from FIG. 5 in perspective representation;
[0021] FIG. 7 is a torque transmission device with a coolant distribution device, as represented in FIGS. 1 to 6 in various views and embodiment examples, in half section;
[0022] FIG. 8 is a view of a longitudinal section through the coolant distribution device represented in FIGS. 1 and 2 ;
[0023] FIG. 9 is a perspective representation of the coolant distribution device represented in FIG. 8 ; and,
[0024] FIG. 10 illustrates five different variants of a coolant distribution device with different geometries.
DETAILED DESCRIPTION OF THE INVENTION
[0025] In FIGS. 1 and 2 a coolant distribution device 1 is represented in perspective in different views. The coolant distribution device 1 serves to distribute the coolant. The coolant is preferably oil, which is used in a wet-running clutch device to cool friction lamellas. The coolant distribution device 1 according to the invention is thus also designated as an oil distributor. The coolant distribution device 1 comprises a receiving plate 2 which essentially has the shape of an annular disk 3 . Teeth 5 , 6 , and 7 , which are coupling elements, project, in the radial direction, outwards from the annular disk 3 . A collar 9 is bent radially inwards from the annular disk 3 . In the collar 9 a plurality of through-openings 11 , 12 is provided, which make possible the passage of coolant in the radial direction. The collar 9 turns into a fastening flange 14 , which comprises several through-holes 16 , 17 . The through-holes 16 , 17 serve for the guiding through of fastening elements 19 with whose aid a coolant distribution element 20 is fastened to the receiving plate 2 .
[0026] The coolant distribution element 20 comprises a plurality of coolant distribution surfaces 21 to 23 , which are distributed uniformly over the circumference. The coolant distribution surfaces 21 to 23 are each bounded by two ribs 25 , 26 ; 26 , 27 ; 27 , 28 . Moreover, the coolant distribution surfaces 21 to 23 are surfaces of ramps which project, in the radial direction, outwards from a plane annular disk surface 30 and have different slopes. On the inside in the radial direction a drive sleeve 32 is mounted on the annular disk surface 30 . The drive sleeve 32 has essentially the shape of a circular cylindrical shell on which two coupling elements 34 , 35 are formed so as to be diametrically opposite one another. The receiving plate 2 , the coolant distribution element 20 , and the drive sleeve 32 can be connected to one another as one piece. However, instead of this, the parts can also be formed separately and fastened to one another with the aid of additional fastening elements such as screws or rivets. It is also possible to connect the individual parts to one another by a material lock, e.g., by welding.
[0027] In FIGS. 3 and 4 a coolant distribution device according to the invention is represented which is a three-part combination consisting of a receiving plate 2 , coolant distribution element 20 , and a drive sleeve 32 . The coolant distribution element 20 is molded from plastic and can be fastened to the receiving plate 2 by snap-on connecting elements or a bayonet catch. Alternatively, the coolant distribution element 20 can also be fastened to the receiving plate 2 with the aid of screws 36 which are plugged into the coolant distribution element 20 via through-holes 38 . The drive sleeve 32 and the receiving plate 2 are two separate sheet metal parts.
[0028] In FIGS. 5 and 6 it is shown that the receiving plate 2 and the coolant distribution element 20 can also be combined as one part in a sheet metal part 40 . The sheet metal part 40 can, for example, be made from sheet metal by stamping and re-forming. The drive sleeve 32 also formed as a sheet metal part can be fastened to the coolant distribution element 20 with the aid of (not represented) riveted bolts. For this purpose the drive sleeve 32 comprises a fastening flange 41 with through-holes 42 . During assembly, the through-holes 42 of the fastening flange 41 are to be brought to cover additional through-holes 43 which are provided in the annular disk surface 30 . In FIG. 6 it is furthermore indicated that the ribs 44 are made to stand out by re-forming of the original sheet metal.
[0029] In FIG. 7 a part of a drive train 51 of a motor vehicle is represented. A wet-running double clutch 56 in the lamellar mode of construction is disposed between a gear mechanism 55 and a drive unit 53 , in particular an internal combustion engine from which a drive shaft 54 projects. Between the drive unit 53 and the double clutch 56 a rotary oscillation damping device 58 is connected. The rotary oscillation damping device 58 is a double-mass flywheel.
[0030] The drive shaft 54 of the internal combustion engine 53 is connected, via screw connections and in such a manner that it is fixed, to an input part of the rotary oscillation damping device 58 . The input part of the rotary oscillation damping device 58 is coupled, with the interposition of coil springs, to an output part of the rotary oscillation damping device 58 . The output part of the rotary oscillation damping device 58 is in turn connected, in such a manner that it cannot turn and via a connecting part with an integrated hub part, to an input part 64 of the double clutch 56 . The clutch input part 64 is connected as one piece to an outer lamella carrier 66 of a first lamellar clutch arrangement 67 . An inner lamella carrier 69 of the first lamellar clutch arrangement 67 is disposed, in the radial direction, within the outer lamella carrier 66 . The inner lamella carrier 69 is fastened, on the inside in the radial direction, to a hub part 71 which is connected, via a toothing and in such a manner that it cannot turn, to a first gear mechanism input shaft 73 .
[0031] The outer lamella carrier 66 of the first lamellar clutch arrangement 67 is connected, via a clutch part 68 and in such a manner that it cannot turn, to an outer lamella carrier 70 of a second lamellar clutch arrangement 72 . An inner lamella carrier 74 of the second lamellar clutch arrangement 72 is disposed, in the radial direction, within the outer lamella carrier 70 and said inner lamella carrier is connected, on the inside in the radial direction and in such a manner that it is fixed, to a hub part 75 . The hub part 75 is connected, via a toothing and in such a manner that it cannot turn, to a second gear mechanism input shaft 76 which is formed as a hollow shaft. In the second gear mechanism shaft 76 the first gear mechanism shaft 73 is disposed in such a manner that it can turn. The two lamellar clutch arrangements 67 and 72 are actuated via actuating levers 77 and 78 whose radially inner ends are supported on actuation bearings. The actuation bearings are actuated in the axial direction with the aid of actuating pistons.
[0032] The actuation force of the actuating lever 78 is transmitted via a pressure piece 81 to a lamella 82 of the lamellar clutch arrangement 72 . In the axial direction, between the pressure piece 81 and the lamella 82 , a receiving plate 2 of a coolant distribution device 1 is, as is represented in the FIGS. 1 to 6 in various forms of embodiment, suspended in the outer lamella carrier 70 . The outer lamella carrier 70 , which is connected, in such a manner that it cannot turn, to the outer lamella carrier 66 , is connected in the manner of a drive to the crankshaft 54 . Thus, the receiving plate 2 is turned during the operation of the internal combustion engine 53 at the rotary speed of the motor. The coolant distribution element 20 of the coolant distribution device 1 is disposed, in the radial direction, within the through-openings 86 , which make possible the passage of coolant in the radial direction through the inner lamella carrier 74 . The drive sleeve 32 of the coolant distribution device 1 is connected to a pump drive tube 84 , which, in turn, is connected, in such a manner that it cannot turn, to a drive pinion of a (not represented) coolant pump.
[0033] In the wet-running double clutch 56 a special coolant, in particular a special coolant oil, is used in order to dissipate the friction heat arising during the operation of the lamellar clutch arrangements 67 and 72 . To cool the friction linings the coolant oil in each case flows through between a steel lamella and a friction lamella, where a temperature change occurs. Through grooves in the friction linings the coolant oil is conducted outwards in the radial direction. In this way the coolant oil is conducted outwards in the radial direction through both lamellar clutch arrangements 67 and 72 . Subsequently, the coolant oil is mixed with oil in a gear mechanism sump. From there it is then pumped to the cooler and then once again into the clutch. In order to supply the lining grooves uniformly with coolant oil, the coolant oil is conveyed via the special geometry of the coolant distribution surfaces to different axial positions. Due to the centrifugal force occurring during operation the coolant oil is ejected outwards in the radial direction onto the clutch linings where it can enter the lining grooves.
[0034] In FIGS. 8 and 9 it is indicated by an arrow 90 that the coolant oil conveyed by the coolant oil pump reaches, from the interior of the drive sleeve 32 and through the drive sleeve 32 , the plane annular disk surface 30 . Through the centrifugal force caused by the rotary speed of the motor the volume flow conveyed by the coolant oil pump is distributed uniformly on the coolant distribution surfaces 21 to 23 , which are formed on the ramps. In so doing, the coolant is accelerated in addition by the ribs 25 to 28 and, at the end of the ramp, sprays off outwards in the radial direction predefined by the different ramp slope angles. Via the number of ramps the amount of coolant oil for a coating can be adjusted. Particularly heavily loaded friction linings can thus be cooled preferentially. The coolant oil spraying off at the end of the ramp is indicated by arrows 91 to 94 . In FIGS. 8 and 9 one sees that the coolant oil sprays off of the different ramps in different axial directions and different tangential directions.
[0035] In FIG. 10 it is indicated that the coolant distribution element can have different ramp geometries 101 to 105 . The direction of rotation in the clockwise sense is indicated in each case by an arrow 100 . The greater the number of ramps is, the more uniformly the individual lining planes can be supplied. However, with too many ramps there is the danger that the oil is made turbulent in an undesirable manner. An uncompromised spraying off of the coolant oil in the predefined direction is made possible by a sharp edge. The corresponding radius is less than 0.5 mm. In 101 it is indicated that the ribs can extend exactly in the radial direction. In 102 it is indicated that the ribs can also extend in the tangential direction. In 103 it is indicated that the ribs each have the form of circular arcs which are disposed in the form of a spiral. In 104 and 105 it is indicated that the ribs can also consist of straight parts combined with circular arcs.
LIST OF REFERENCE NUMBERS
[0000]
1 Coolant distribution device
2 Receiving plate
3 Annular disk
5 Coupling element
6 Coupling element
7 Coupling element
9 Collar
11 Through-opening
12 Through-opening
14 Fastening flange
16 Through-hole
17 Through-hole
19 Fastening element
20 Coolant distribution element
21 Coolant distribution surfaces
22 Coolant distribution surfaces
23 Coolant distribution surfaces
25 Rib
26 Rib
27 Rib
28 Rib
30 Annular surface
32 Drive sleeve
34 Coupling element
35 Coupling element
36 Screws
38 Through-hole
40 Sheet metal part
41 Fastening flange
42 Through-hole
43 Through-hole
44 Rib
51 Drive train
53 Drive unit
54 Crankshaft
55 Gear mechanism
56 Double clutch
58 Rotary oscillation damping device
64 Coupling input part
66 Outer lamella carrier
67 First lamellar clutch arrangement
68 Coupling part
69 Inner lamella carrier
70 Outer lamella carrier
71 Hub part
72 Second lamella clutch arrangement
73 Gear mechanism input shaft
74 Inner lamella carrier
75 Hub part
76 Gear mechanism input shaft
77 Actuation lever
78 Actuation lever
81 Pressure piece
82 Lamella
84 Pump drive tube
86 Through-opening
90 Arrow
91 Arrow
92 Arrow
93 Arrow
94 Arrow
100 Arrow
101 Coolant distribution element
102 Coolant distribution element
103 Coolant distribution element
104 Coolant distribution element
105 Coolant distribution element | A coolant distribution device for a wet-running clutch device and comprising several coolant distribution surfaces along which coolant is conveyed outwards in the radial direction. In order to increase the service lifetime of a wet-running clutch device the coolant distribution surfaces are implemented so that the coolant conveyed outwards in the radial direction has different axial coolant spray-off points and/or coolant spray-off devices. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation from U.S. patent application Ser. No. 14/191,591, filed on Feb. 27, 2014, and entitled METHOD AND APPARATUS OF APPLYING CALL SUPPRESSION MEASURES TO RESTRICT PHONE CALLS, which is a continuation from U.S. patent application Ser. No. 13/329,812, filed on Dec. 19, 2011, now issued U.S. Pat. No. 8,681,967, and entitled METHOD AND APPARATUS OF APPLYING CALL SUPPRESSION MEASURES TO RESTRICT PHONE CALLS, each of which is incorporated by reference herein in their entirety.
TECHNICAL FIELD OF THE INVENTION
This invention relates to a method and apparatus of restricting undesired phone calls to an end user, and in particular, to providing a phone system that automatically applies rules and regulations to a telephone network to regulate the times, frequency and/or source of telephone calls to the end user.
BACKGROUND OF THE INVENTION
Users may be called by business organizations at any time on their home phone, mobile phone or even their office telephone. Generally, the calls received by any individual user may be from a business or organization that the user has no desire to contact. The calls may be soliciting services or charities of which the user is not interested in participating or offering money to support.
Various state and Federal government laws, rules and regulations offer users privacy from unwanted calls. However, those laws may be difficult to enforce and violations may be even more difficult to report. Current phone systems are not equipped with options to automatically apply state and Federal rules with regard to limits on the hours, days and times that solicitations are made to the user. Business organization may have no desire to violate the terms of these government rules and regulations. However, keeping track of the dates, times and localities being called on any given day may be difficult.
SUMMARY OF THE INVENTION
One embodiment of the present invention may include a method of determining whether to perform telephone call blocking. The method may include initiating a telephone call from a call server, determining whether the call is a solicitation call, and determining the area code of the call and performing a lookup operation of the area code in a call suppression database. The method may also provide retrieving at least one call block entry for a current day from the call suppression database, and comparing the area code to the at least one call block entry for the current day to determine whether the call should be blocked.
Another example embodiment of the present invention may include an apparatus configured to determine whether to perform telephone call blocking. The apparatus may include a transmitter configured to transmit a telephone call. The apparatus may also include a processor configured to determine whether the call is a solicitation call, determine the area code of the call and perform a lookup operation of the area code in a call suppression database, and retrieve at least one call block entry for a current day from the call suppression database. The processor is also configured to compare the area code to the at least one call block entry for the current day to determine whether the call should be blocked.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an example call suppression communication system according to example embodiments of the present invention.
FIGS. 2A and 2B illustrate example call suppression graphical user interfaces according to example embodiments of the present invention.
FIGS. 3A and 3B illustrate yet another example call suppression graphical user interface according to example embodiments of the present invention.
FIGS. 3C and 3D illustrate an editable date suppression graphical user interface according to example embodiments of the present invention.
FIGS. 3E and 3F illustrate another editable date suppression graphical user interface according to example embodiments of the present invention
FIG. 4 illustrates a flow diagram of an example method according to example embodiments of the present invention.
FIG. 5 illustrates another flow diagram of an example method according to example embodiments of the present invention.
FIG. 6 illustrates an example graphical user interface of a call regulation system according to example embodiments of the present invention.
FIG. 7 illustrates a database logic diagram illustrating the logical relationships between the various entities.
FIG. 8 illustrates a network entity that may include memory, software code and other computer processing hardware, according to example embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
It will be readily understood that the components of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of a method, apparatus, and system, as represented in the attached figures, is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention.
The features, structures, or characteristics of the invention described throughout this specification may be combined in any suitable manner in one or more embodiments. For example, the usage of the phrases “example embodiments”, “some embodiments”, or other similar language, throughout this specification refers to the fact that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present invention. Thus, appearances of the phrases “example embodiments”, “in some embodiments”, “in other embodiments”, or other similar language, throughout this specification do not necessarily all refer to the same group of embodiments, and the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
In addition, while the term “message” has been used in the description of embodiments of the present invention, the invention may be applied to many types of network data, such as packet, frame, datagram, etc. For purposes of this invention, the term “message” also includes packet, frame, datagram, and any equivalents thereof. Furthermore, while certain types of messages and signaling are depicted in exemplary embodiments of the invention, the invention is not limited to a certain type of message, and the invention is not limited to a certain type of signaling.
FIG. 1 illustrates a telephone communication regulation system according to example embodiments of the present invention. Referring to FIG. 1 , the telephone communication system may be regulated on the side of the business organization 102 to provide an automated call dialing regulator based on local, state and/or federal regulations. The regulations may be stored in a telephony regulation database 104 . In this example, the business organization 102 includes a telephony server used to provide dialing features for the telemarketers 108 to dial-out to the end users (private residences 110 A, 110 B and 110 C). The telemarketers 108 are also in communication with a text messaging engine server 103 which communicates over a public land mobile network (PLMN) 105 . A regulation database 104 provides a record of the various different regulations corresponding to the various different demographics. A regulation service 107 provides an engine to communicate those regulations to the call and text message initiation platforms 106 and 103 , respectively.
The regulations of each of the three respective private residences 110 A, 110 B and 110 C may be based on Federal, state and local government laws and regulations. As may be observed from FIG. 1A , each of the three example private residences are located in different states across the United States. Each of the private residences is located in a geographically unique area that may be identified by a zip code, area code, postal code, etc., each of which may be used by the telephony regulation database 104 to distinguish certain regulations from one another. For example, the telephony regulation database may organize regulations by state, zip code and/or area code. Such regulations may be regularly updated and downloaded to the database 104 for cross-referencing by the telephony server 106 when attempting to dial a particular user located in a particular geographical area.
Phone calls originated from the telephony server 106 may be automatically selected from a spreadsheet of end users' telephone numbers. Once the call is dialed, the call in progress may be handed over to a telemarketer 108 automatically via a call distribution scheme handled by the telephony server 106 . The call may be routed to the public switched telephone network (PSTN) 108 , which routes the call to its intended destination. The business organization 102 may be responsible for regulating its own phone calling procedures and may require a call regulation system to be adapted to its internal calling infrastructure. Alternatively, the call dialing may be performed with the assistance of a third party calling service that matches individual end users or call destinations to the geographical regulations that are enacted within the end users' locations.
The regulation service 107 may provide regulation information to the calling and text messaging platforms. For instance, the regulation service 107 may be utilized by the telephony server 106 and/or text messaging server 103 , which are responsible for sending notifications to the intended recipients. For example, the regulation service 107 may provide a list of zones that are eligible for a regulation to be applied, a list of zone types. (Federal, State, Area Code, etc.), a list of channels (delivery methods) that are eligible for a regulation block to be applied, a listing of all active one time regulation blocks for a given date and time, a listing of all active reoccurring regulation blocks for a given date and time, a listing of active one time regulation blocks that are currently in effect based on the start and end times for the regulation, adjusted for the local time zone and broken down by area code, the most granular zone type available, a listing of active reoccurring regulation blocks that are currently in effect, adjusted for the local time zone and broken down by area code, the most granular zone type available. Any regulations with an ‘allowed window’ are not included. Other features of the regulation service 107 may allow the deactivation of existing one time and reoccurring regulations, a way to create a new one time block or reoccurring regulation blocks for a given zone and channel, and a way to log notifications that have been blocked due to the existence of a specific one time or reoccurring regulation.
FIG. 2A illustrates an example graphical user interface (GUI) application used to initiate a call suppression procedure, according to example embodiments. Referring to FIG. 2A , a window 200 provides a user with a view of the basic call suppression setup for a statewide selection procedure. For example, certain states with stringent regulations that are not cohesive to the business organizations interests or communication procedures may be selected in a state exclusion window 202 . Other states that are desirable for call solicitation purposes may be included in a state inclusion window 204 . A particular date 206 may be added as day that calls will be suppressed or not allowed for any of the selected states. A note section 208 may provide a place to comment about the suppression date, and a result section 210 may summarize the actions performed by the call administrator setting up the call regulation system.
FIG. 2B illustrates another example graphical user interface (GUI) application used to initiate a call suppression procedure, according to example embodiments. Referring to FIG. 2B , a window 220 provides a user with another view of the basic call suppression setup for a statewide selection procedure. A particular day(s) of the week 222 may be selected as a day that receives reoccurring call suppression. Similar to FIG. 2A , the excluded states 226 and included states 224 may be setup manually by the administrator. A day of the week suppression menu 228 may offer an easy way to select the day(s) of the week that calls should be suppressed. In addition an hourly schedule 230 may be setup to provide a time-frame during which calls may be processed and dialed to the selected states on the allowed days. Multiple day suppressions for one or more states may be added at one time. If “allow calling hours” is unchecked, when the user selects the save button, the call suppression will be in effect the entire day from 12:00:00 AM to 11:59:59 PM.
FIG. 3A illustrates a GUI 300 used to inform the user of a call suppression conflict with a previously selected call suppression schedule, according to example embodiments. When such a scheduling conflict is presented, the user may accept the overriding new schedule or cancel and revert back to the previous call suppression schedule.
FIG. 3B illustrates a call solicitation suppression schedule 310 . The schedule may have been previously setup and modified to include additional holidays or days of the week when calls should be suppressed. In menu 310 , the user may be able to view values for existing call date suppressions. Fields, such as zone 311 , zone type 312 , date 313 , day of week 314 , status 315 , note 316 and actions 317 correspond to each call suppression entry. The zone entry 311 will display the state name and may also include the zip code and area code. The zone type 312 displays the type of zone, such as state, zip code, area code, federal zone, etc. The action column 317 will display a link to edit the record or remove the record from the list.
The user may be able to sort and filter each column except for the actions column 317 , which provides options to remove or edit the existing call suppression entry. Selecting the remove option will delete the entry from the database 104 . If a record is active, within 15 minutes of removing the record, the system will acknowledge removal of the suppression. Selecting the edit action will open the screen shown in FIGS. 3C and/or 3 D. If the status of a date suppression record is ‘complete’, the user will not be able to edit or remove the record. If the status of a date suppression record is ‘pending’, the user will not be able to edit the record.
FIGS. 3C and 3D illustrate an editable date suppression graphical user interface according to example embodiments of the present invention. Referring to FIG. 3C , date suppression menu 320 provides a particular zone which has been selected “Louisiana” corresponding to a particular date 322 that a call suppression is supposed to be enacted. In FIG. 3D , the menu 330 provides feedback 332 from the system that a call suppression schedule is already in existence for the selected zone and date. The save button on the edit date suppression menu 330 will remain inactive until a valid date and note is entered into the screen.
FIGS. 3E and 3F illustrate another editable date suppression graphical user interface according to example embodiments of the present invention. Referring to FIG. 3E , a menu option 340 provides feedback 342 that a date may be selected that is equal to or greater than today, to guide the user to select an appropriate date that may be accepted by the date suppression schedule. FIG. 3F illustrates further details of the existing call suppression entries 350 . These entries are similar to those illustrated in FIG. 3B , however, additional entries, such as start time 351 and stop time 352 may be used to create a window of time when call suppressions may be active or inactive.
FIG. 4 illustrates a flow diagram of an example method according to example embodiments of the present invention. The call suppression system of the business organization 102 may follow a particular logic or method of operation when determining whether a call should be suppressed or routed. For example, a call may be initiated at operation 402 . The call may be designated as a solicitation type of call at operation 404 . If the call is not a solicitation, it may be routed without delay at operation 418 . If the call is a solicitation, the area code of the call may be looked up at operation 406 . Next, a determination may be made as to whether a current call block is in place for today at operation 408 . In this operation, the telephony regulation database 104 may be accessed by the telephony server 106 to view the call blocks that are scheduled for the current day.
If the call block does exist, the current area code of the call will be matched against the existing call block entry at operation 420 . If the current area code of the call is part of the blocked entries, then the result will be marked as a “regulation block” at operation 422 , which flags the call as “not routed.” Alternatively, if there is no call block present for the current day, or the call block does not prevent the call from being routed, an additional regulation may be checked, such as whether the call is violating a Federal calling window regulation (e.g., no calls allowed 9 PM through 8 AM, etc.), at operation 410 . If the Federal window is being violated, the call may be marked as a “regulation block” at operation 412 . If the Federal window is not being violated, then state laws may be checked by mapping the area code of the call to the particular state at operation 414 . If a state regulation does exist, the state's calling window may be checked at operation 416 , and if it is not in violation the call may be routed at operation 418 .
FIG. 5 illustrates another flow diagram of an example method according to example embodiments of the present invention. Referring to FIG. 5 , when a call is placed, the call area code is referenced at operation 502 to determine whether a call block is active at operation 504 . If so, the current time corresponding to the area code's location is determined and that local time is used as a basis to determine whether a block is present at operation 506 . If so, the call is marked as a regulation block in the database 104 and a response message is generated based on the time, location and date referenced from the database 104 at operation 508 .
FIG. 6 illustrates an example graphical user interface of a call regulation system according to example embodiments of the present invention. Referring to FIG. 6 , the interface 600 provides support for various different compliance tools, which are accessed through a centralized interface. The interface provides a way to enables the call processing platform to block solicitation-based communications driven by continually evolving Federal and State regulations.
Through the interface 600 , compliance leaders who monitor the dynamic regulatory environments that impact business-to-consumer communications (e.g., FTC, FCC, HIPAA, and State Regulations) have the capability to initiate global and state-specific call blocking rules, including the ability to apply specific dates, recurring days, and time blocking settings for specific hours in a day.
An input interface 602 included in the top section of the user interface 600 provides the capability to select the specific states that will be included in the suppression. The central portion 604 of the user interface focuses on the specific dates or days of the week that will be evaluated for the blocked timeframe as well as notes regarding the reason for the regulation. The lower section 606 summarizes the blocks that have been added and the active call filters and regulations that are presently active.
Storage of the criteria input is housed in the regulation database. From these settings, the platform evaluates the communication delivery times based on the time zone of the message recipients to determine when calls can be placed based on the configuration settings specified by the conditions for —each regulation.
FIG. 7 illustrates a logic diagram of the database entity relationship diagram. Referring to FIG. 7 , a ‘BlockingZoneTypes’ entity is configured to store the categories under which ‘BlockingZones’ 704 can be categorized. This is generally used to denote the scope in area for which a regulation block is intended. Examples of ‘BlockingZoneType’ entries include Federal, State, Area Code, etc. ‘BlockingZones’ 704 contains all of the zones that are available to be associated with a particular regulation. Examples include Federal, Alabama, Florida, 205 , 251 , 850 , etc. ‘BlockingChannels’ 712 provides a listing of the delivery method affected by a regulation (e.g., voice calls and text messages).
‘BlockingByDates’ 702 stores regulations where the scope of the regulation is to be in effect one particular time. These regulations are associated with specific channels and zones and are in effect for the date range stored in the table. Once a regulation has been entered, it cannot be deleted or modified, only deactivated. The date and user associated with the regulation's entry is also stored.
‘BlockingByDateLogs’ 708 stores a history of voice calls that have been blocked due to a one time regulation. ‘BlockingByDOW’ 706 collects regulations where the scope of the regulation is reoccurring for a zone and channel for a specific day of the week. The ‘AllowStartTime’ and ‘AllowEndTime’ fields of 706 provide for exceptions of a daily reoccurring regulation for a portion of the day. For example, all calls to Louisiana are blocked on Sundays with the exception of the hours of 9:00 AM to 5:00 PM. Once a regulation has been entered, it cannot be deleted or modified, only deactivated. The date and user associated with the regulation's entry is also stored. The ‘BlockingByDOWLogs’ entity 714 stores a history of voice calls that have been blocked due to a reoccurring regulation.
The operations of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a computer program executed by a processor, or in a combination of the two. A computer program may be embodied on a computer readable medium, such as a storage medium. For example, a computer program may reside in random access memory (“RAM”), flash memory, read-only memory (“ROM”), erasable programmable read-only memory (“EPROM”), electrically erasable programmable read-only memory (“EEPROM”), registers, hard disk, a removable disk, a compact disk read-only memory (“CD-ROM”), or any other form of storage medium known in the art.
An exemplary storage medium may be coupled to the processor such that the processor may read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an application specific integrated circuit (“ASIC”). In the alternative, the processor and the storage medium may reside as discrete components. For example FIG. 8 illustrates an example network element 800 , which may represent any of the above-described network components of FIG. 1 .
As illustrated in FIG. 8 , a memory 810 and a processor 820 may be discrete components of the network entity 800 that are used to execute an application or set of operations. The application may be coded in software in a computer language understood by the processor 820 , and stored in a computer readable medium, such as, the memory 810 . Furthermore, a software module 830 may be another discrete entity that is part of the network entity 800 , and which contains software instructions that may be executed by the processor 820 . In addition to the above noted components of the network entity 800 , the network entity 800 may also have a transmitter and receiver pair configured to receive and transmit communication signals (not shown).
One example embodiment of the present invention may include a method of
While preferred embodiments of the present invention have been described, it is to be understood that the embodiments described are illustrative only and the scope of the invention is to be defined solely by the appended claims when considered with a full range of equivalents and modifications (e.g., protocols, hardware devices, software platforms etc.) thereto. | A determination of whether to perform telephone call blocking includes initiating a telephone call from a call server, determining whether the call is a solicitation call and determining the area code of the call and performing a lookup operation of the area code in a call suppression database. The process may also include retrieving a call block entry for a current day from the call suppression database, and comparing the area code to the call block entry for the current day to determine whether the call should be blocked. | 7 |
FIELD OF THE INVENTION
[0001] The invention disclosed herein relates to improvements in plungers used in gas/fluid lift systems in wells producing both fluids and gases, such as petroleum and natural gas, under variable pressures. More specifically, the present invention is concerned with a pad subassembly of a particular configuration for sealingly and slidingly engaging a plunger within the well tubulars.
BACKGROUND OF THE INVENTION
[0002] Petroleum and natural gas producing wells typically employ a plunger disposed within tubing of the well. The plunger provides lift to liquids accumulated above the plunger in the wellbore, powered by gas and pressures below the plunger from formations in the earth which are in communication with the lower part of the well, below the plunger, relying on variable fluid pressures within the well-bore, above and below the plunger. The well-bore is typically lined with tubular materials of relatively uniform internal surface diameter, but operators expect the internal passageway of the tubular to be somewhat uneven or imperfect. It is optimal if the gap between the outer sides of the plunger and the inner surface of the tubular is kept small, as this will make the lift system operate more efficiently, as less pressure and fluid from beneath will bypass the plunger, and less fluid above the plunger can drop below, past the plunger. In essence, it would be ideal to have a plunger which was perfectly sealed to the tubular but moved frictionlessly along its length in either direction, powered by fluid pressure variations above and below the plunger (at least on the up-stroke lift portion of the plunger system's cycle). It is also useful to have replaceable surfaces on the outer sides of the plunger as that surface will wear from contact with the tubular's inner wall; an outer surface of different materials from the plunger's body may also be advantageous as different materials can be used to provide different structural, mass and density, permeability, chemical reactivity, formability or machineability, resilience, tooling, frictional, or wear or other characteristics as required for manufacturing, operation, assembly, repair, or function in place of different parts of the plunger.
[0003] In the prior art, a variety of mechanical plungers for use in gas-lift systems for production of fluids from wells have been disclosed or are known. Each has disadvantages. Some examples follow:
[0004] U.S. Pat. No. 6,725,916 to Gray et al. (“Gray”) discloses a plunger with a system of floating, spring-loaded pads between a plunger's body and the tubular within which it operates, together with a novel seal and internal passage, with the aim of facilitating rapid descent of the plunger from its upper-most part of a stroke in its lift-cycle (by opening the inner passage at the top of the stroke, and reclosing it at the bottom). Gray provides a good example of state-of-the art pad systems. Gray's “jacket” comprises a series of interlocking pads held to the plunger's body but spring-loaded to bias outwardly toward the tubular's walls. The aspect in Gray's jacket which is relevant, is the provision of “labyrinthine passages” between the jacket's elements (the spaces between the pads), which in Gray are formed by the interlocking teeth of each pad with the adjacent pads—when the jacket (pads) is expanded, the spaces between the interlocking pads increases, providing larger and larger flow-paths for fluid communication past the plunger in the tubular during use. This is undesirable, and Gray has attempted to resolve the issue by making these passages between the interlocking pads “labyrinthine” or following a toothed, notched, or circuitous pathway. Notably, the notch-finger interlocking region between pads in Gray are also stepped and matched with a step in the extended end of each finger (and a mating void in the recess or notch into which the finger fits when assembled) which is stepped up and down in a direction radial to the linear centre of the plunger (to its longitudinal axis), while the rest of the adjacent pads' mating surface edges are not stepped in that way. While providing some resistance to fluid flow past the plunger in the annulus between the plunger and the tubular, there is still a void and passageway for fluid communication with a large cross-section.
[0005] US Patent Application 2012/0080196 by Laing (“Laing”) discloses a plunger lift and safety valve system with a variable outside diameter plunger where the diameter is variable by the retraction and expansion of pads deployed about the outer circumference of the plunger's body between the plunger and the tubular (when expanded) or between the plunger and a smaller-diameter (than the tubular) safety valve (when the pads are retracted). The pads are spring-biased toward the inner surface of the tubular from the plunger, and are interlocking with each other to permit them to radially expand and contract but to be firmly held linearly in position with the plunger (linearly along the direction of the plunger's longitudinal axis). The relevance of Laing as an example of prior art plunger pad systems is that the pads interlock and are biased outwardly by springs, but when expanded the spaces between the pads open up, providing a large cross-section (viewed longitudinally along the plunger's axis to a cross-section of the plunger and pads), the openings between the pads are the relevant flow-paths for fluid flow past the plunger, which is undesirable both in terms of efficiency of operation, as well as contamination of the plunger's working parts with materials produced with the hydrocarbon fluids in the well (debris, sand, silt, corrosive materials, etc).
[0006] It is an object of the present invention to obviate or mitigate at least one disadvantage of previous related art.
SUMMARY OF THE INVENTION
[0007] Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] In the drawings, like elements are assigned like reference numerals. The drawings are not necessarily to scale, with the emphasis instead placed upon the principles of the present invention. Additionally, each of the embodiments depicted are but one of a number of possible arrangements utilizing the fundamental concepts of the present invention. The drawings are briefly described as follows:
[0009] FIG. 1 is a longitudinal drawing blending a cross-section and surface elevation of a preferred assembled plunger assembly of the invention;
[0010] FIG. 2 shows a side elevation of the external surfaces of an exemplar of adjacent pads to show an aspect of their interlocking features;
[0011] FIGS. 3 , 4 , and 5 show cross-sections perpendicular to the longitudinal axis of a preferred plunger assembly, each figure with a slight variant of the pads' overlap features, highlighting their approximately axial interfaces;
[0012] FIGS. 6 and 7 show elevations in perspective of the inner surface and the outer surface of a preferred pad element of the invention; and
[0013] FIGS. 8 and 9 show elevations in perspective of the plunger's body and a preferred retaining means for holding the pad elements of the invention in place.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] The present invention provides an improved plunger assembly for use in downhole tubulars in wells that produce fluids and/or gases under variable pressure. In particular, the present invention provides a subassembly of expandable interlocking pad elements radially arrayed around the plunger body for sealing an annulus between the plunger and its pads and the tubular within which the plunger is deployed as part of a gas-lift system.
[0015] The present invention more specifically provides for an improved configuration of overlapped joints between adjacent pad elements which, when the pad elements are expanded within the tubular of the well, slidably sealing the plunger to the tubular. The pad elements are configured to overlap both longitudinally, by mating notch and finger joints or similar geometric arrangements, and radially, along the length of the gap or slot along the edge of each mating notch and finger by inner and outer surfaces radially spaced from the plunger's axis, such that one edge of a pad element will radially overlap the mating edge of an adjacent pad element. This can have the effect of reducing the available flowpath past the plunger along the seams between pad elements by reducing the cross-sectional surface area of the voids in those seams accessible to fluids in the annulus between the tubular and the plunger's outer surfaces when the pad elements are expanded.
[0016] When describing the present invention, all terms not defined herein have their common art-recognized meanings. To the extent that the following description is of a specific embodiment or a particular use of the invention, it is intended to be illustrative only, and not limiting of the claimed invention, which should be given the broadest interpretation consistent with the description as a whole.
[0017] Referring now to FIG. 1 , therein illustrated is a preferred plunger assembly of the present invention generally designated 100 . The plunger assembly 100 comprises a plunger body 200 that can be composed of any rigid material, including any metal or metal alloy, rigid plastics and polymers, ceramics, etc., or any combinations thereof.
[0018] As illustrated in both FIGS. 1 and 8 , the body of the plunger 200 includes an elongated central mandrel 1 for support. The mandrel 1 can be substantially cylindrical in shape and in the form of an elongated rigid non-flexible solid rod.
[0019] The plunger body 200 may include a fishing profile 2 that has a head or cap 4 located above a neck 3 , as depicted in the drawings. Also illustrated in the drawings is the bottom face 13 of the fishing profile.
[0020] Referring now to FIGS. 1-7 , depicted therein is the preferred pad subassembly 300 of the present invention. The pad subassembly 300 generally provides a system of expandable interlocking pad elements radially arrayed around the body of the plunger 200 for sealing the annulus between the plunger and the pad assembly and the tubular within which the plunger is deployed as part of a gas-lift system. In the preferred embodiment, four pad elements 14 , 15 , 16 and 17 can collectively form the pad subassembly 300 . While four pad elements are depicted, the pad subassembly may comprise alternate numbers of pad elements. The pad elements can be made of any relatively rigid material such as metal or metal alloys, rigid plastics or rubber, graphite, etc, or any combinations thereof. In a preferred embodiment, the pad elements may be composed of a different material from the plunger's body 200 , that may be advantageously used to provide different structural, mass and density, permeability, chemical reactivity, formability or machineability, resilience, tooling, frictional, or wear or other characteristics as required for manufacturing, operation, assembly, repair, or function, in different parts of the plunger.
[0021] The plunger's pad elements 14 , 15 , 16 , 17 are generally adapted to engage or interlock with each other, slidably held to the plunger body 200 , between the body and the inner surface of a tubular. The interlocking nature of the pad elements 14 , 15 , 16 , 17 is both to permit the elements to move away from each other when the diameter of the assembly is expanded, and to move radially from the plunger when the diameter of the assembly is expanded.
[0022] As illustrated in the drawings, the pad elements 14 , 15 , 16 , 17 can be generally rectangular in shape. However, the elements may be a variety of geometric shapes, sizes, and dimensions. Further, in a preferred embodiment, the pad elements 14 , 15 , 16 , 17 may have a convex or substantially convex outer surface with a concave or substantially concave inner surface.
[0023] Referring now to FIGS. 6 and 7 depicted therein are elevations in perspective of the inner and outer surfaces of a preferred embodiment of one of the pad elements 14 . As shown, a pad element 14 may have a generally rectangular shape having a substantially convex outer surface and a generally cylindrical inner surface.
[0024] A pad element of the present invention may comprise a tabbed or protruding portion on a first side and a notched or slotted portion on a second side, with the tabbed or slotted portion being mutually engageable with the corresponding tabbed or slotted portion of an adjacent element, so as to minimize or prevent leakage from between the elements.
[0025] As illustrated, in the preferred embodiment, the tabbed portion of the pad element 14 comprises an outer tongue 14 a which can be defined by an upper side face 14 b and a lower side face 14 c , and an inner tongue 14 v which can be defined by an upper side face 14 y and an inner end face 14 u . The inner tongue 14 v may be stepped inward, such that the outer tongue 14 a can be elevated from the inner tongue 14 v , and the inner tongue 14 v may extend out from the outer tongue 14 a . Also, depicted in FIG. 7 is a side skirt upper face 14 w and a side skirt lower face 14 x of a pad element 14 . The side skirt upper face 14 w may be continuous with the inner tongue 14 v and situated generally above and stepped inward from the outer tongue 14 a , such that the outer tongue 14 a may be elevated from the side skirt upper face 14 w . The side skirt lower face 14 x may be continuous with the inner tongue 14 v and situated generally below and stepped inward from the outer tongue 14 a , such that the outer tongue 14 a maybe elevated from the side skirt lower face 14 x.
[0026] As illustrated in FIGS. 6 and 7 , the notched portion of a pad element 14 may be defined by an upper side face 14 d and lower side face 14 e . Also depicted on the inner surface, is an internal face of the notch 14 r , an internal face above the notch 14 s and an internal face below the notch 14 t.
[0027] Referring now to FIGS. 2-5 , depicted therein are the preferred engaging or interlocking capabilities of the pad elements of the present invention. FIGS. 3 , 4 , and 5 particularly depict aspects of the overlap features of pad elements 14 , 15 , 16 , 17 .
[0028] FIG. 2 is a side elevation that depicts the external surfaces of adjacent pad elements 14 , 15 to show an aspect of their interlocking features. As illustrated, the outer tongue 15 b of a pad element 15 engages or interlocks with the notch portion of an adjacent pad element 14 . In particular, FIG. 2 shows the mated external surfaces between the pad elements 14 , 15 as the outer tongue 15 a of the tabbed portion engages the notched portion. As depicted, the notch upper side face 14 d of a pad element 14 may directly contact the outer tongue upper side face 15 b of an adjacent pad element 15 . The outer tongue lower side face 15 c may also come into direct contact with the notch lower side face 14 e . FIG. 3 provides a bottom cross-sectional view of the pad subassembly 300 with each of its constituent pad elements 14 , 15 , 16 , 17 as the pad subassembly 300 is expanded.
[0029] Referring now to FIG. 4 , illustrated therein is a top cross-sectional view of the pad subassembly 300 of the present invention, depicting particular overlap features of adjacent pad elements 14 , 15 , 16 , 17 . More specifically, overlapping of the tabbed portion by an inner surface of the notched portion is illustrated. In the preferred embodiment depicted, there may be an overlap of the side skirt upper face 14 w , 15 w , 16 w , 17 w of a pad element by the internal face above the notch 14 s , 15 s , 16 s , 17 s of an adjacent pad element. For example, the internal face above the notch 14 s of pad element 14 can overlap the side skirt upper face 15 w of adjacent pad element 15 . Also, as can be seen, such an overlap could be maintained even as the pad subassembly 300 was further expanded.
[0030] Referring now to FIG. 5 , illustrated therein is a top cross-sectional view of the pad subassembly 300 of the present invention depicting a different aspect of the overlap features of adjacent pad elements 14 , 15 , 16 , 17 . In particular, depicted therein is the overlap of the inner tongue outer face 14 v , 15 v , 16 v , 17 v of a pad element by the notch internal face 14 r , 15 r , 16 r , 17 r of an adjacent pad element. For example, the notch internal face 14 r of pad element 14 can overlap the outer face of the inner tongue 15 v of adjacent pad element 15 . Also, as can be seen, such overlap could be maintained even as the subassembly was further expanded.
[0031] While it may be known to have the gaps between pad elements form a labyrinthine route for fluid to flow past the plunger, by defining the gaps between the pad elements by shaping notches and fingers or tabs in the overall shapes of the pad elements as interlocking “T” shapes, or other mating and moveable geometries, the present invention provides a second type of overlap, radially between adjacent pad elements, such that the pad elements slide apart with restricted flow paths linearly along the direction of the plunger body's axis being restricted by tight gaps between adjacent pad elements' interfaces which can be perpendicular to the plunger body's axis which may not expand when the pad elements slide apart, but also providing a second slideable interface between adjacent pad elements which can overlap along a circumferential direction along a radial surface which can be within the radial depth of the pad elements, where a radially inner surface of a pad element along the gap between two pad elements can mate with a radially outer surface of an adjacent pad element along the same gap.
[0032] The pad element subassembly 300 of the present invention can be biased outwardly for slidably engaging the well tubular, while providing an external seal against the interior of the tubulars. The pad element subassembly 300 has the largest diameter of the plunger assembly when it is in its most radially expanded position and sealingly engaging the tubular. The pad elements may be biased outwardly against the tubulars by built up internal pressure and/or springs.
[0033] As illustrated in FIGS. 1 and 8 , the pad subassembly of the preferred embodiment may have biasing means comprising springs 22 , such as a helically wound spring, coil spring, leaf spring or any other element which has the ability to rebound or recoil after being compressed. The springs 22 may be disposed between the pump assembly body 200 and the inner surface of pad elements 14 , 15 , 16 , 17 . In a preferred embodiment, there are two springs 22 between each pad element 14 , 15 , 16 , 17 preferably disposed at an upper end and lower end of each element. Recesses on the upper end 10 and the lower end 9 of the pump assembly 200 may accommodate and hold the spring in place. As depicted in FIG. 6 , the underside of a pad element 14 may also comprise an upper spring recess 14 n and a lower spring recess 14 o.
[0034] The radial surface of the pad subassembly 300 may be either parallel to the outer surface of the plunger body, or may be sloped with relation to a circumferential theoretical surface within the plungers' body thickness, and if sloped, could provide a further biasing force to assist or perhaps replace some or all of the radially expanding forces typically provided by springs or other similar mechanisms (hydraulic or mechanical) between the plunger body and any or each pad element to bias the pad(s) to expand to meet the tubular.
[0035] Referring back to FIG. 1 , the plunger assembly 100 of the present invention comprises a pad subassembly 300 disposed about the plunger body 200 that is preferably held in place by retaining means, such as an upper and a lower retaining ring 18 . FIG. 9 specifically depicts the preferred retaining means for holding the pad elements of the present invention in place. Retaining rings 18 may be substantially cylindrical in shape having a hollow inner surface of slightly larger diameter than the plunger body 200 with a shape that can correspond with that of the plunger body 200 .
[0036] In a particularly preferred embodiment, the leading and/or trailing edge at the upper and/or lower end of the pad elements 14 , 15 , 16 , 17 may be skirted to slide and seal with a retaining ring in the assembled plunger assembly 300 , which may improve their seal to the plunger body 200 .
[0037] As illustrated in FIGS. 6 and 7 , the upper and the lower end of a pad element can comprise a corresponding upper and lower end skirt. In the preferred embodiment depicted, the upper end skirt has a notch side 14 g and a tongue side 14 h , whereas the lower end skirt can also comprise a notch side 14 j and a tongue side 14 g . The pad elements of the preferred embodiment may also comprise an upper tab 14 f and a lower tab 14 i which may be stepped outward from the skirt. An upper tab 14 f may also extend generally upwards from the skirt while a lower tab 14 i may also extend generally downwards from the skirt.
[0038] Referring back to FIG. 9 , a retaining ring 18 may further comprise a plurality of end skirt recesses 18 b for overlapping with the notch side 14 g , 15 g , 16 g , 17 g and the tongue side 14 h , 15 h , 16 h , 17 h of the upper end skirt of a pad element, with respect to an upper retaining ring 18 , or the notch side 14 j , 15 j , 16 j , 17 j and the tongue side 14 k , 15 k , 16 k , 17 k of the lower end skirt of a pad element, with respect to a lower retaining ring 18 . The retaining ring 18 may further comprise a plurality of pad tab recesses 18 a that overlap a pad element upper tab 14 f , 15 f , 16 f , 17 f , with respect to an upper retaining ring 18 , or a pad element lower tab 14 i , 15 i , 16 i , 17 i , with respect to a lower retaining ring 18 . Also depicted is a thru bore 18 c for a locking pin 19 for securing the retaining rings 18 . As illustrated in FIG. 8 , the plunger body comprises a corresponding thru bore for a lower retaining ring locking pin 6 a and a thru bore for the upper retaining ring locking pin 6 b.
[0039] In a preferred embodiment, the underside or inner surface of the pad element further comprises an upper and a lower rib stepped inwardly from the skirt at the upper and lower ends of the pad element, respectively. As illustrated in FIGS. 6 and 7 , a pad element 14 can comprise an upper internal rib 14 l and lower internal rib 14 p that protrude radially inwardly toward the body 200 of the plunger. The internal ribs 14 l , 14 p of the preferred embodiment may further comprise a tabbed portion extending vertically from the ribs 14 l , 14 p . As illustrated in FIGS. 6 and 7 , an upper tab internal rib 14 m is depicted extending substantially vertically and upwards from the upper internal rib 14 l . A lower tab internal rib 14 q is also depicted extending substantially vertically and downwards from the lower internal rib 14 p.
[0040] The plunger assembly of the present invention may further comprise a bottom sub 21 on the bottom end of the plunger body 200 , as illustrated in FIG. 1 . The bottom sub 21 may have tapered end. Referring also to FIG. 8 , illustrated therein is a threaded connection 5 a bottom sub locking pin 23 and thru bore for the locking pin 6 .
[0041] In the preceding description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the embodiments of the invention. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the invention.
[0042] The above-described embodiments of the invention are intended to be examples only. Alterations, modifications and variations can be effected to the particular embodiments by those of skill in the art without departing from the scope of the invention, which is defined solely by the claims appended hereto.
LEGEND FOR DRAWINGS
[0043] Legend for FIGS. 1-9
1 . Mandrel 2 . Fishing Profile (contains 3 and 4 ) 3 . Fishing Neck 4 . Fishing Head or Cap 5 . Bottom Threaded Connection 6 . Thru Bore for Bottom Sub Locking Pin
6 a . Thru Bore for lower Retaining Ring locking pin 6 b . Thru bore for upper Retaining Ring locking pin 7 . Lower Tab ( 14 Q) recess 8 . Lower pad internal rib ( 14 p ) recess 9 . Pad coil spring recess lower end 10 . Pad coil spring recess upper end 11 . Upper pad internal rib ( 14 L) recess 12 . Upper pad tab ( 14 m ) recess 13 . Fishing Profile bottom face 14 . Plunger Pad Element
a. Outer tongue b. Outer tongue upper side face c. Outer tongue lower side face d. Notch upper side face e. Notch lower side face f. Pad upper tab outer surface g. Upper end skirt notch side h. Upper end skirt tongue side i. Pad lower tab outer surface j. Lower end skirt notch side k. Lower end skirt tongue side l. Upper internal rib m. Upper tab internal rib n. Upper coil spring recess o. Lower coil spring recess P. Lower internal rib q. Lower tab internal rib r. Notch internal face s. Internal face above notch t. Internal face below notch u. Inner tongue end face v. Inner tongue outer face w. Side skirt upper face x. Side skirt lower face y. Inner tongue upper side face 15 . Plunger Pad Element
a. a thru y same as for 14 16 . Plunger Pad Element
a. a thru y same as for 14 17 . Plunger Pad Element
a. a thru y same as for 14 18 . Retaining Ring
a. Pad tab recess (overlaps 14 f or 14 i ) b. End skirt recess (overlaps 14 j & 14 k or 14 g & 14 h ) c. Thru bore for locking pin 19 . Locking pin for retaining ring ( 18 ) 20 . Lock ring for bottom sub locking pin ( 23 )
a. Lock ring access hole for locking pin b. Lock ring interior surface 21 . Bottom sub 22 . Pad coil spring 23 . Bottom sub locking pin 24 . Pad internal face 25 . Mandrel face 26 . Bottom sub thru bore for locking pin | An improved plunger with expandable mating pad elements arrayed circumferentially about the plunger's body sealed to the plunger and biased to expand the plunger assembly's outer circumferential surface toward the inner surface of the tubular within which the plunger assembly is designed to operate. The gaps between the pad elements are minimized by having the adjacent pad elements slidable against each other along two sets of surfaces along essentially the length of the interface between adjacent pad elements, one surface set being approximately axial to the plunger and the other set being approximately radial to the plunger's longitudinal axis, and in this way reducing the available pathway in the gap between adjacent pad elements for fluid to bypass the plunger assembly. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This case claims priority of the following provisional applications:
[0002] (1) U.S. provisional application No. 61/207,467; and
[0003] (2) U.S. provisional application No. 61/273,814.
[0004] This case is a Continuation-in-Part and claims priority of co-pending U.S. Ser. No. 12/621,451 titled “Multiple-Cavity Antenna” and filed on Nov. 18, 2009.
[0005] This case claims priority to PCT case titled “Multiple-Cavity Antenna”, which was submitted to the USPTO/Mail Stop PCT on Feb. 15, 2010 via FedEx Airbill 8682 2381 6624.
FIELD OF THE INVENTION
[0006] The present invention relates to antenna design for radio communication in general, and, more particularly, to antenna design for Radio-Frequency IDentification (RFID) systems.
BACKGROUND OF THE INVENTION
[0007] Radio communication systems have existed for over a century. During this period of time, antenna designers have generated a wide variety of antenna designs with the goal of achieving good performance in a variety of operating conditions.
[0008] Generally, the goal of the antenna designer when designing, for example, a receiving antenna, is to maximize power transfer between an electromagnetic signal incident on the antenna, and the resulting electrical signal generated by the antenna. The higher the power transfer, the higher the received signal-to-noise ratio, which usually results in better receiver performance.
[0009] Also, traditionally, radio receivers have comprised electronic circuitry and a separate receiving antenna interconnected to one another through a suitable cable connection. In such systems, antenna designers must consider the distorting influence of the cable connection and the electronic circuitry on the electromagnetic behavior of the antenna.
[0010] More recently, with the advent of small radio systems based on integrated circuit technology, it has become possible to make so-called Radio-Frequency IDentification (RFID) systems, wherein an entire radio receiver is housed in a package much smaller than the receiving antenna. In such systems, the almost-complete elimination of the distorting influence of the cable connection and the electronic circuitry enables novel antenna designs.
[0011] So-called passive RFID receivers can be much smaller than the receiving antenna in part because they do not require a power supply. Power to operate the receiver is derived from the received radio signal itself. The signal generated by the receiving antenna is rectified by one or more diodes to yield a direct-current (DC) voltage that is used to power the receiver.
[0012] Ideal diodes are perfect conductors when a forward voltage is applied and are perfect insulators when a reverse voltage is applied. Real diodes only approximate this behavior. In particular, real diodes require a minimum forward voltage before becoming good conductors. Accordingly, the signal generated by the receiving antenna, must have a voltage higher than the minimum required by the diodes, before a DC voltage becomes available to power the RFID receiver.
[0013] So, in contrast with traditional antenna design, the goal for the design of passive-RFID-receiver antennas is to maximize not the received-signal power, but rather the received-signal voltage.
[0014] It is well known in the art that antennas are reciprocal devices, meaning that an antenna that is used as a transmitting antenna can also be used as a receiving antenna, and vice versa. Furthermore, there is a one-to-one correspondence between the behavior of an antenna used as a receiving antenna and the behavior of the same antenna used as a transmitting antenna. This property of antennas is known in the art as “reciprocity.”
[0015] An antenna used as a transmitting antenna accepts an electrical signal applied at an input port and produces a transmitted electromagnetic signal that propagates through three-dimensional space. It is well known in the art how to represent such a transmitted electromagnetic signal as a vector in a vector space, for example, as a superposition of spherical harmonics. The behavior of a transmitting antenna at a given frequency can be fully characterized by reporting, for example, the spherical-harmonic components of the transmitted electromagnetic signal that it generates in response to a test electrical signal at that frequency that is applied to the antenna's input port.
[0016] Such a characterization can be used to derive, unambiguously, the behavior of the same antenna when it is used as a receiving antenna. In this case, the input port becomes an output port that generates an output electrical signal in response to an incident electromagnetic signal propagating through three-dimensional space. The incident electromagnetic signal can be specified by, for example, by specifying its spherical-harmonic components. The resulting electrical signal can then be derived through a scalar product with the spherical-harmonic components of the transmitted electromagnetic signal at the same frequency, as is well known in the art.
[0017] A consequence of reciprocity is that an antenna can be fully characterized in terms of its properties as either a transmitting antenna or as a receiving antenna. A full characterization of an antenna when used in one mode (transmitting or receiving) uniquely and unambiguously defines the properties of the antenna when used in the other mode.
[0018] For example, in order to understand or measure the radiation pattern of an antenna it is frequently easier to feed an electric signal into the antenna and then observe the electromagnetic field generated by the antenna. This task can be performed experimentally or computationally. The radiation pattern of the antenna that is obtained through this method also applies when the antenna is used as a receiving antenna. Hereinafter, antennas will be interchangeably referred to as receiving or transmitting, and their properties will be discussed as they apply to either transmission or reception, as convenient to achieve clarity. It will be clear to those skilled in the art how to apply what is said about an antenna used in one mode (receiving or transmitting) to the same antenna used in the other mode.
[0019] FIG. 1 depicts monopole antenna 100 in accordance with the prior art. Monopole antenna 100 comprises monopole 110 , ground plane 120 and co-axial cable connection 130 . Monopole antenna 100 is a very common type of antenna and is representative of how many antennas operate. When an electrical signal is applied to co-axial cable connection 130 , an electric field appears between monopole 110 and ground plane 120 . If the electrical signal has a frequency at or near the so-called “resonant” frequency of the antenna, a large fraction of the power of the electrical signal is converted into an electromagnetic signal that is radiated by the antenna. If the electrical signal has a frequency that is substantially different from the resonant frequency of the antenna, a relatively small fraction of the signal's power is radiated; most of the power is reflected back into the co-axial cable connection.
[0020] In principle, it is possible to make an antenna that radiates efficiently at many frequencies, without exhibiting a band of resonance. In practice, it is difficult to make such antennas, and resonant structures (hereinafter also referred to as “resonators”) are commonly used to make antennas that radiate efficiently.
[0021] FIG. 2 depicts resonant structure 200 , which is an example of a type of resonant structure commonly used to make antennas in the prior art. Resonant structure 200 comprises a length of wire 240 bent in the shape of the letter U, with an input-output port 220 comprising connection points 230 - 1 and 230 - 2 . As depicted in FIG. 2 , the two connection points are attached to the two ends of the wire.
[0022] The frequency of resonance of resonant structure 200 depends on its length. The structure can be modeled as a twin-lead transmission line 210 with a short at one end (i.e., the end opposite input-output port 220 ). The structure is resonant at a frequency for which the length of the transmission line is about one quarter of a wavelength. The range of frequencies near the resonant frequency over which the resonant structure exhibits acceptably good performance is known as the “band of resonance.”
[0023] Resonant structure 200 exhibits resonance in a manner similar to monopole antenna 100 . Near the resonant frequency, the electromagnetic fields generated by the voltages and currents on wire 240 become stronger, and a larger fraction of the power of an electrical signal applied to input-output port 220 is radiated as an electromagnetic signal. Accordingly, resonant structures that exhibit this behavior are referred to as “electromagnetically-resonant.”
[0024] FIG. 3 depicts folded-dipole antenna 300 , which is an example of a common type of antenna in the prior art. Folded-dipole antenna 300 can be modeled as being composed of two instances of resonant structure 200 connected in series. When used as a transmitting antenna, an electrical signal is applied through balanced transmission line 320 .
[0025] Although folded-dipole antenna 300 can be modeled as being composed of two instances of resonant structure 200 connected in series, the signal that it generates when used as a receiving antenna is not the sum of the signals that each instance of resonant structure 200 would generate if used by itself because of the mutual coupling between the two instances of resonant structure 200 .
[0026] FIG. 4 depicts antenna-with-load-element 400 , which is an example of a type of antenna in the prior art for RFID systems known as RFID tags. Antenna-with-load-element 400 comprises: conductive sheets 410 - 1 , and 410 - 2 , electrical connection 420 , connection points 440 - 1 and 440 - 2 , and load element 430 , interrelated as shown.
[0027] Conductive sheets 410 - 1 and 410 - 2 , together with electrical connection 420 , form resonant structure 450 . Load element 430 receives the signal generated by resonant structure 450 through connection points 440 - 1 and 440 - 2 . When used to implement an RFID tag, load element 430 is small relatively to the size of conductive sheets 410 - 1 and 410 - 2 .
[0028] To implement an RFID tag, load element 430 acts as both a receiver and a transmitter. In particular, in a passive RFID tag, transmission is accomplished through a technique known as “modulated backscatter” wherein load element 430 controls the impedance that it presents to the received signal. Modulated backscatter is based on the fact that, in any radio receiver, a portion of the electromagnetic signal incident on the receiving antenna is reflected. The amplitude and phase of the reflected signal depend on the impedance connected to the antenna port, so that load element 430 modulates the reflected signal by controlling its own impedance.
[0029] The impedance of an RFID load element depends on the design and implementation of the device and, typically, it is non-linear, meaning that is varies as a function of the amplitude of the applied signal. As a consequence, the goal of maximizing received-signal voltage is difficult to achieve. There is a need for methods to couple an antenna to an RFID load element that achieve the desired impedance match.
SUMMARY OF THE INVENTION
[0030] Embodiments of the present invention comprise a resonant structure, an RFID load element, and a floating coupling element. One of the two terminals of the RFID load element is connected directly to the resonant structure, and the other terminal is connected to the floating coupling element. The resonant structure can be realized, for example, as a resonant cavity, as is well known in the art. The floating coupling element is electrically isolated from the resonant structure, and its size, shape and position, relative to the resonant structure, are adjusted so as to achieve the desired impedance match. In particular, the electromagnetic field that forms in the volume of space between the floating coupling element and the resonant structure, and around the floating coupling element, provides the desired coupling between the load element and the resonant structure. The volume of space between the floating coupling element and the resonant structure can be regarded a second cavity, the resonant structure being the first cavity. The size, shape and other physical and electrical parameters of this second cavity determine the shape and behavior of the electromagnetic field and the coupling that it provides. The advantage provided by the floating coupling element derives from the availability of these parameters, that the antenna designer can adjust to achieve a particular coupling. The impedance match between the load element and the resonant structure depends on the coupling, and the flexibility provided by the floating coupling element makes it easier to achieve a good impedance match. Hereinafter we will refer to the floating coupling element as “floating element” with the understanding that its purpose is to provide coupling between the load element and the resonant structure.
[0031] In the prior art, both terminals of the load element are usually directly connected to one or more resonant structures. In some prior-art implementations, one or both terminals of the load element are not connected. Embodiments of the present invention achieve a better impedance match through the use of the floating coupling element. The ability to vary the shape, size and position of the floating coupling element provide antenna designers with additional parameters that they can adjust, through simulation or prototyping, to achieve the desired impedance match.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 depicts a monopole antenna in the prior art.
[0033] FIG. 2 depicts a resonant structure in the prior art.
[0034] FIG. 3 depicts a folded-dipole antenna in the prior art.
[0035] FIG. 4 depicts an example of a type of antenna in the prior art for RFID tags.
[0036] FIG. 5 depicts a single-cavity antenna with floating element in accordance with a first illustrative embodiment of the present invention.
[0037] FIG. 6 depicts a single-cavity antenna with floating element and dielectric in accordance with a second illustrative embodiment of the present invention.
DETAILED DESCRIPTION
[0038] FIG. 5 depicts single-cavity antenna with floating element 500 in accordance with a first illustrative embodiment of the present invention. Single-cavity antenna with floating element 500 comprises: conductive sheets 510 - 1 , and 510 - 2 , electrical connection 520 , connection points 540 - 1 and 540 - 2 , load element 530 , and floating element 570 , positioned and interrelated as shown. In particular, floating element 570 is a flat piece of conductive material parallel to, and at distance 560 from, conductive sheet 510 - 1 ; conductive sheets 510 - 1 and 510 - 2 , together with electrical connection 520 , form resonant structure 550 ; and load element 530 is electrically connected between resonant structure 550 and floating element 570 through connection points 540 - 1 and 540 - 2 .
[0039] Conductive sheets 510 - 1 and 510 - 2 , and electrical connection 520 are identical to conductive sheets 410 - 1 and 410 - 2 , and electrical connection 420 of FIG. 4 . They form resonant structure 550 , which is identical to resonant structure 450 . But load element 530 can be different from load element 430 because it does not need to have the same impedance.
[0040] The purpose of floating element 570 is to couple connection point 540 - 2 to resonant structure 550 without the need for a direct electrical connection. Floating element 570 is electrically isolated from conductive sheet 510 - 1 . Coupling between floating element 570 and conductive sheet 510 - 1 occurs through electro-magnetic fields that develop between floating element 570 and conductive sheet 510 - 1 when the antenna is used to receive a radio signal.
[0041] The size of floating element 570 , and its distance from conductive sheet 510 - 1 , are not negligible, compared to the size parameters of resonant structure 550 . Examples of such size parameters are: the lengths and widths of conductive sheets 510 - 1 and 510 - 2 , the distance between the two sheets, the relative position of one sheet with respect to the other. Because of its non-negligible size and distance from sheet 510 - 1 , the impedance that is coupled to load element 530 is different from the impedance that is coupled to load element 430 in the prior art. The precise value of the impedance can be adjusted by varying the size and shape of floating element 570 , and by varying its position relative to conductive sheet 510 - 1 . The exact values that achieve a particular impedance that is desirable in a particular implementation can be derived through techniques well known in the art such as simulation or prototyping.
[0042] Although the shape of floating element 570 is depicted as a rectangle in FIG. 5 , it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention wherein the shape is different. In particular, the shape of floating element 570 affects the impedance coupled to load element 630 , and it is one of the parameters that can be varied for the purpose of achieving a desired impedance. For example, and without limitation, the shape of floating element 570 , can be a regular or irregular polygon, a circle or ellipse, a serpentine shape, a multi-pointed star.
[0043] Although floating element 570 is depicted as flat, it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention wherein floating element 570 is not flat. For example, and without limitation: floating element 570 can be a piece of conductive material with non-negligible thickness, and its thickness can be an additional parameter that can be adjusted to achieve a desired impedance; floating element 570 can be shaped as a dome, or as a more complex three-dimensional structure; floating element 570 can be realized as one or more wires arranged in a three-dimensional shape, wherein the diameter of the wires can be an additional parameter that can be adjusted to achieve a desired impedance.
[0044] Although floating element 570 is depicted as parallel to conductive sheet 510 - 1 , it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention wherein floating element 570 is not parallel to conductive sheet 510 - 1 . In particular, the exact angle and orientation of floating element 570 relative to conductive sheet 510 - 1 affect the impedance coupled to load element 530 , and are additional parameters that can be varied for the purpose of achieving a desired impedance.
[0045] Although floating element 570 is depicted as floating unsupported in mid air relative to sheet 510 - 1 , it will be clear to those skilled in the art how to support floating element 570 . For example, and without limitation, non-conductive supporting devices such as plastic or teflon screws, or spacers; or glue can be used to support floating element 570 . Alternatively, it is possible to make load element 530 with sufficient mechanical strength and rigidity such that the connection to load element 530 through connection point 540 - 2 is sufficient to support floating element 570 in the desired position. One alternative method to support floating element 570 is presented below as part of a second illustrative embodiment of the present invention. Other methods to support floating element 570 will be clear to those skilled in the art.
[0046] Although floating element 570 is depicted as being at a distance 560 , from conductive sheet 510 - 1 , that is less than the distance between sheet 510 - 1 and sheet 510 - 2 , it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention wherein floating element 570 is at a different distance. For example, and without limitation, floating element 570 can be in the same plane as sheet 510 - 2 , so that distance 560 is the same as the distance between sheet 510 - 1 and sheet 510 - 2 ; or distance 560 can be larger than the distance between sheet 510 - 1 and sheet 510 - 2 .
[0047] FIG. 6 depicts single-cavity antenna with floating element and dielectric 600 in accordance with a second illustrative embodiment of the present invention. Single-cavity antenna with floating element and dielectric 600 comprises: conductive sheets 610 - 1 , and 610 - 2 , electrical connection 620 , connection points 640 - 1 and 640 - 2 , load element 630 , floating element 670 , positioned and interrelated as shown.
[0048] Conductive sheets 610 - 1 and 610 - 2 , and electrical connection 620 are identical to conductive sheets 510 - 1 and 510 - 2 , and electrical connection 520 of FIG. 5 . They form resonant structure 650 , which is identical to resonant structure 550 . Load element 630 , connection points 640 - 1 and 640 - 2 , and floating element 670 are identical, respectively, to load element 530 , connection points 540 - 1 and 540 - 2 , and floating element 570 . The salient difference between this second embodiment and the first embodiment depicted in FIG. 5 is the presence of dielectric 670 between floating element 670 and conductive sheet 610 - 1 .
[0049] Dielectric 610 is made of dielectric material whose dielectric properties provide additional parameters that can be varied for the purpose of achieving a desired impedance. Also, dielectric 610 can be made sufficiently strong to provide mechanical support for floating element 670 .
[0050] Although dielectric 610 is depicted as having the shape of a parallelepiped whose size and shape match the size and shape of floating element 670 , it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention wherein dielectric 610 has other sizes and shapes. For example, and without limitation:
i. dielectric 610 can occupy only part of the space between floating element 670 and conductive sheet 610 - 1 ; ii. dielectric 610 can extend beyond the outline of floating element 670 over portions of or over the entirety of the perimeter of floating element 670 ; iii. dielectric 610 can comprise different regions made from different dielectric materials; iv. dielectric 610 can be part of a printed-circuit board, resonant structure 650 can be realized as a patch antenna, and floating element 670 can be realized as a patch of conductive material; or v. a combination of i, ii, iii, or iv.
[0056] Although FIG. 5 and FIG. 6 depict embodiments of the present invention comprising a single-cavity resonant structure, it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention that comprise multiple resonant structures or multiple resonant cavities. Also, although the resonant cavities depicted in FIG. 5 and FIG. 6 do not comprise a dielectric, it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention with resonant cavities that comprise a dielectric. For example, and without limitation, dielectric 670 can be realized as a single block of dielectric material that extends beyond the outline of floating element 670 and into the space between conductive sheets 610 - 1 and 610 - 2 .
[0057] Although this disclosure sets forth embodiments of the present invention as applicable for implementing RFID systems, it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention that are applicable to other types of radio-communication systems. For example, and without limitation, a radio receiver or transmitter characterized by a high input or output impedance can advantageously utilize an antenna with a floating coupling element in accordance with an embodiment of the present invention.
[0058] It is to be understood that this disclosure teaches just one or more examples of one or more illustrative embodiments, and that many variations of the invention can easily be devised by those skilled in the art after reading this disclosure, and that the scope of the present invention is to be determined by the following claims. | An antenna for a Radio-Frequency IDentification (RFID) system is disclosed that comprises a resonant structure, an RFID load element, and a floating coupling element. One of the two terminals of the RFID load element is connected directly to the resonant structure, and the other terminal is connected to the floating coupling element. The floating coupling element is electrically isolated from the resonant structure; its presence provides an improved impedance match to the RFID load element. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. application Ser. No.: 09/861,443 filed on May 18, 2001, now U.S. Pat. No. 6,881,645 the disclosure of which in its entirety is incorporated by reference herein.
This application claims priority to Korean Patent Application No. 2000-47585, filed on Aug. 17, 2000 and Korean Patent Application No. 2000-64715, filed on Nov. 11, 2000, the contents of both of which are herein incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention generally relates to a method of forming a semiconductor device on a silicon on insulator (SOI) type substrate, and a semiconductor device formed thereby. More specifically, a method of preventing a SOI layer from bending around an active region when trench device isolation is performed on the SOI-type substrate and a semiconductor device formed thereby.
2. Discussion of Related Art
When adjacent semiconductor layers having different impurity types are formed the interface between the layers acts as an isolation barrier. Commonly employed junction-type isolation techniques are usually not suitable for high-voltage junctions in semiconductor layers because the voltage-resistance characteristics are weak at high voltage junction surfaces. Further, unwanted current may flow a junction depletion layer caused by a radiation ray such as a gamma ray, rendering the isolation technique inefficient in a high-radiation circumstance. Therefore, a SOI-type semiconductor device where a device region is completely isolated by an insulating layer is generally used in high-performance semiconductor devices such as a central processing unit (CPU).
Mesa, local oxidation of silicon (LOCOS), and shallow trench isolation (STI) techniques have widely been used to isolate devices on an SOI-type substrate. The STI technique prevents a bird's beak phenomenon that occurs in the LOCOS technique. The bird's beak phenomenon practically decreases a device formation area. Accordingly, the STI technique is generally applied to a highly integrated semiconductor device.
When the STI technique is applied for device isolation on an SOI-type substrate, an undesirable bending phenomenon occurs in a silicon layer composing an active region due to a structural characteristic of the substrate. This problem is illustrated in FIGS. 1 through 3 .
Referring to FIG. 1 , a typical SOI-type substrate may comprise a lower silicon layer 10 , a buried silicon oxide layer 11 , and an SOI layer 13 that are sequentially stacked. The SOI layer 13 composes an active region. In order to perform STI, a pad oxide layer 15 and a silicon nitride layer 17 serving as an etch-stop layer are sequentially stacked on an SOI layer of an SOI-type substrate. Using a photoresist layer 19 the silicon nitride layer 17 is then patterned to form a pattern made of silicon nitride.
Referring to FIG. 2 , using the pattern of the silicon nitride layer 17 as an etching mask, the exposed pad oxide layer 15 and the SOI layer thereunder are etched to form a trench and a patterned SOI layer 23 . Therefore, the bottom of the trench is formed of the silicon oxide layer 11 .
Referring to FIG. 3 , a sidewall oxide layer 25 is formed on the sidewalls of the trench. The sidewall oxide layer 25 results from a heat treatment for curing crystalline defects. An interface between the patterned SOI layer 23 ′ and the buried silicon oxide layer 11 serves as an oxygen diffusion path. Because oxygen is smoothly supplied to the exposed sidewall according to a trench shape, an oxide layer is extended from the trench into an active region, on a bottom of the patterned SOI layer 23 ′. Accordingly, a wedging thermal oxide layer 24 is penetrated between the SOI layer 23 ′ and the buried silicon oxide layer. The material of the thermal oxide wedges 24 are of greater volume than the original silicon and therefore expand, thereby lifting the immediately adjacent portion 26 of the patterned SOI layer 23 ′ from the trench. Hence, the SOI layer is bent.
When bending occurs, stress is applied to the SOI layer by a lifting force from the sidewall of the trench. If the following ion implantation process is then carried out, a crystalline defect is created in the SOI layer. The created crystalline defect is easily expanded by the lifting force, and increases junction leakage currents. Even though the crystalline defect does not occur during ion implantation, a depth of the SOI layer is partially changed and that of practical ion implantation is also changed by the bending. This leads to instability of threshold voltages (A comparison of oxidation induced stress and defectivity in SIMOX and bonded SOI wafers may be found in Proceedings of the 1997 IEEE International SOI Conference , October 1997; Stress Induced Defect and Transistor Leakage for Shallow Trench Isolated SOI: IEEE Electron Device Letters, Vol. 20, No. 5, May 1999).
Under conditions that form sidewall oxide layers to a thickness of about 240 Å, a part of an SOI layer up to 4000 Å from the sidewall trench can be lifted. Even though the bending phenomenon is changed according to the degree and condition of sidewall oxidation, it cannot completely be prevented. It is therefore desirable to provide a method or methods of manufacturing semiconductor devices in a manner that eliminates or at least alleviates such bending.
SUMMARY OF THE INVENTION
Disclosed herein are methods for preventing bending of a patterned SOI layer during trench sidewall oxidation, a preferred method comprising providing a patterned SOI layer having at least one trench, said patterned SOI layer disposed upon an underlying buried silicon oxide layer; and blocking diffusion of oxygen between said patterned SOI and buried silicon oxide layer.
According to an aspect of the invention, there is provided a method wherein a nitrogen-containing layer is formed on an overall interface between a SOI layer and a buried silicon oxide layer that are included in a SOI-type substrate. A shallow trench isolation process is then carried out. As a method of forming the nitrogen-containing layer in the overall SOI-type substrate, deposition or nitridation is carried out in a nitrogen-containing gas ambient at the state of forming the SOI substrate. Alternatively, after forming the STI substrate, nitrogen-containing ion implantation is carried out.
According to a preferred method, a SOI layer is etched to form a trench on a SOI-type substrate. The SOI-type substrate having the trench is tilted to an angle and revolved. The angle of tilt will generally be held constant. A nitrogen-containing ion implantation is then carried out to form a nitrogen-containing layer on an interface between a SOI layer and a buried silicon oxide layer at an area adjacent to the trench.
According to another aspect of the invention, a SOI layer is etched to form a trench. A single-crystalline silicon layer is formed on a sidewall of the trench. Preferably, an etch-stop layer is stacked on a SOI-type substrate. A pattern to expose a trench area is formed. Using the pattern as an etching mask, a SOI layer of the SOI-type substrate is etched to form a trench. An amorphous silicon layer is conformally stacked on an overall surface of the SOI-type substrate. An annealing process is performed to obtain a solid phase epitaxial growth (SPE) of the amorphous silicon layer contacted with the sidewall of the trench composed of the SOI layer. A buried oxide layer is stacked to fill the trench. A planarization etching process is carried out to remove the buried oxide layer on the active region. In other words, the trench is formed in the SOI-type substrate and a temporary oxygen barrier layer is conformally stacked on the amorphous silicon layer. An SPE of the stacked amorphous silicon layer is got. In this case, the buried oxide layer is generally made of chemical vapor deposition (CVD) oxide.
According to still another aspect of the invention, a SOI layer is etched for device isolation. A trench is formed and a CVD oxide layer is conformally stacked on an overall surface of a substrate where the trench is formed. In this case, a liner for oxygen barrier can be stacked on an internal wall of the trench. Generally, the liner is stacked using a CVD stacking manner of a silicon nitride layer.
According to further another aspect of the invention, a trench for device isolation is formed on a SOI-type substrate and a rapid thermal processing (RTP) is performed to form an oxide layer. A liner for oxygen barrier may be formed on the oxide layer. Generally, the liner is stacked using a CVD stacking manner of a silicon nitride layer.
To achieve the above aspect of the invention, there is provided a semiconductor device for trench device isolation. According to one construction, the semiconductor device includes a lower silicon layer, a buried silicon oxide layer, and a SOI layer that are sequentially stacked on an active region. At least around the active region, a nitrogen-containing layer is formed between the buried silicon oxide layer and the SOI layer.
In a preferred semiconductor device, an oxide layer is formed on a lateral portion where a trench device isolation layer is contacted with the active region. The oxide layer is generally made of thermal oxide formed in a furnace, but may be made of CVD oxide or rapid thermal oxidation (RTO) oxide. Except the lateral portion, most of the trench device isolation layer is made of oxide to fill the trench.
According to another aspect of the semiconductor device for trench device isolation, the semiconductor device includes a lower silicon layer, a buried silicon oxide layer, a SOI layer that are sequentially stacked on an active region. A sidewall of the active region, contacted with a trench device isolation layer, is made of single-crystalline silicon by SPE. In this case, a thermal oxide layer and a silicon nitride liner may be formed on the single-crystalline silicon layer.
According to a preferred method, there is disclosed a method for preventing bending phenomenon of a silicon on insulator (SOI) layer, the method comprising the forming of a SOI-type substrate including a lower silicon layer, a buried oxide silicon layer, a SOI layer, and a nitrogen-containing layer between the buried oxide silicon layer and the SOI layer; and etching the SOI layer of the SOI-type substrate to form a trench for device isolation.
A further aspect of the method is disclosed wherein the nitrogen-containing layer is formed by implanting nitrogen ions in the step of forming the SOI-type substrate.
Still yet a further aspect of the method is disclosed wherein the nitrogen ions are implanted in a state of forming a pad oxide layer on a surface of the SOI layer.
According to a preferred method for preventing a bending phenomenon of a silicon on insulator (SOI) layer, there is disclosed a method comprising the etching of a SOI layer of a SOI-type substrate including a lower silicon layer, a buried oxide silicon layer, and a SOI layer to form a trench; and tilting the SOI-type substrate where the trench is formed and implanting nitrogen ions thereinto, forming a nitrogen-containing layer between the SOI layer and the buried oxide silicon layer at an area adjacent to the trench.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 to FIG. 3 are cross-sectional flow diagrams showing a bending phenomenon occurring when trench device isolation is performed on a conventional SOI substrate.
FIG. 4 to FIG. 6 are cross-sectional flow diagrams showing a feature in accordance with a first embodiment of the present invention.
FIG. 7 is a cross-sectional diagram showing a feature in accordance with a second embodiment of the present invention.
FIG. 8 to FIG. 9 are cross-sectional diagrams showing a feature in accordance with a third embodiment of the present invention.
FIG. 10 is a cross-sectional diagram showing a feature in accordance with a fourth embodiment of the present invention.
FIG. 11 to FIG. 14 are cross-sectional diagrams showing a flow in accordance with a fifth embodiment of the present invention.
FIG. 15 to FIG. 18 are cross-sectional diagrams showing a flow in accordance with a sixth embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Six preferred methods according to embodiments of the present invention for preventing an SOI layer from bending and a semiconductor device formed by the methods are described.
First Method
FIG. 4 to FIG. 6 are flow diagrams showing forming a nitrogen-containing layer on an interface between an SOI layer and a silicon oxide layer according to one aspect of the invention.
Referring to FIG. 4 , an SOI-type substrate comprises a lower silicon layer 110 , a buried silicon oxide layer 111 , and an SOI layer 113 for forming a device that are sequentially stacked. A pad oxide layer 115 is formed on a surface of the SOI-type substrate. Nitrogen-containing ions are implanted into an overall surface of the SOI-type substrate, forming a nitrogen-containing layer 131 .
Ion implantation energy enables the implanted ions to have a peak value of concentration at an interface between the SOI layer 113 and the buried silicon oxide layer 111 . The ion implantation energy is changed according to a thickness of the pad oxide layer 115 and the SOI layer 113 , but generally has a range of 30-100 keV.
Referring to FIG. 5 , a silicon nitride layer 117 serving as an etch-stop layer for forming a trench is stacked on an SOI layer where a pad oxide layer 115 is formed. Using a conventional (or other suitable) photolithographic process, a photoresist pattern 119 to expose a device isolation trench area is formed on the silicon nitride layer 117 . Using the photoresist pattern 119 as an etching mask, the silicon nitride layer 117 and the pad oxide layer are etched. The SOI layer is then etched to expose a buried silicon oxide layer. With an patterned SOI layer 123 formed, a trench is formed. Before etching the SOI layer, the photoresist pattern 119 may be removed.
Referring to FIG. 6 , in order to cure a crystalline defect of a trench sidewall that is attacked in a trench etching step, thermal oxidation is carried out to an SOI-type substrate where the trench is formed. The thermal oxidation may then be carried out, such as in a furnace at a temperature of 900° C. for 15 minutes. A thermal oxide layer 25 typically having a thickness of 200–300 Å is formed on the trench sidewalls defined by the patterned SOI layer 123 . A nitrogen-containing layer 131 such as a silicon nitride layer or a silicon oxide nitride layer is formed at an interface between the patterned SOI layer 123 and the buried silicon oxide layer 111 . Therefore, the interface serving as an oxygen-diffusing path is eliminated, because oxygen is not easily diffused between a silicon layer and a silicon nitride layer or a silicon oxynitride layer. Although not shown in detail, it may be mentioned in passing that the pad oxide layer 115 , where thickly formed on the trench sidewall, will expand and slightly bend the silicon nitride layer above it.
In this embodiment, a pad oxide layer 115 on an SOI layer is shown, but it should be noted that forming the pad oxide layer is not essential. After thermal oxidation, a silicon nitride liner may be formed on the trench and then a buried oxide layer, such as a CVD oxide layer, filled in the trench to achieve device isolation.
Second Method
FIG. 7 shows a state of implanting nitrogen ions into a trench that is formed on an SOI substrate comprising a lower silicon layer 110 , a buried silicon oxide layer 111 , and an patterned SOI layer 123 . Using a pattern of an etch-stop layer as an etching mask, the patterned SOI layer 123 is etched to form the trench. When implanting the nitrogen ions thereinto, a lower energy of about 10 keV is applied. Because a substrate where the trench is formed is tilted at an angle (usually about 15°), arrows indicating ion-implanting directions are also tilted. In the ion-implanting process, the substrate is revolved to enable the nitrogen ions to be implanted into exposed sidewalls of all the layers of the trench. In this case, a partial area between the SOI layer and the buried silicon oxide layer is significant. Around an active region contacted with the trench, the nitrogen ions are implanted to form a nitrogen-containing layer therebetween. In the following annealing process of an oxygen ambient, the nitrogen-containing layer will be expanded through an interface therebetween. In spite of a constant width, the nitrogen-containing layer serves to prevent partial oxidation of a lower part of the SOI layer.
After forming an oxide layer or a nitride layer on the sidewalls, filling a remaining part of the trench with an insulating layer is performed.
Third Method
FIG. 8 shows a state of stacking a silicon oxide layer on an overall surface of an SOI-type substrate where an patterned SOI layer 123 and a trench are formed, using a CVD technique. The CVD technique is a low pressure chemical vapor deposition (LPCVD) that is performed at a temperature of about 700–750° C. The LPCVD technique at a temperature of about 700° C. or more, is helpful to cure crystalline defects caused by etching. The CVD oxide layer 132 serves as a protection layer of the trench sidewalls. Nonetheless, a bending phenomenon does not occur because a wedged thermal oxide layer is not formed due to the low pressures and temperature of the LPCVD process.
Referring to FIG. 9 , an optional additional procedure of further stacking an oxygen barrier layer 133 is shown. To prevent an SOI layer from bending upon subsequent oxidation in a state shown in FIG. 8 , an oxidation barrier layer 133 is deposited on a CVD oxide layer 132 to a thickness of 30–300 Å. The oxidation barrier layer 133 may be made of Si 3 N 4 , SiON, or AlO 3 . The subsequent oxidation is to form a screen oxide layer and a gate oxide layer on an active region, comprising a patterned SOI layer 123 , before implanting ions into the SOI layer. Subsequent oxidation may additionally or alternatively be performed to oxidize a sidewall of a polysilicon gate electrode.
Fourth Method
Referring now to FIG. 10 , rapid thermal oxidation (RTO) for device isolation is carried out on an SOI-type substrate where a trench is etched and formed. Unlike a thermal oxidation in a conventional furnace, the thermal oxidation is carried out on the sidewalls of a silicon layer, namely the patterned SOI layer 123 , at a temperature of about 950–1180° C. for about 30–200 seconds. This leads to formation of a sidewall oxide layer 125 . Diffusion of oxygen through an interface between the oxide layer and the silicon layer so as to oxidize the silicon layer is in proportion to the processing temperature and time. Thus, because the processing time is shortened, oxidation and its resultant bending are reduced.
Fifth Method
Referring to FIG. 11 , there is a silicon nitride layer pattern 117 ′ for forming a trench on an SOI-type substrate where a patterned SOI layer 123 and the trench are formed by etching an SOI layer. An amorphous silicon layer 151 is then conformally stacked to a thickness of about 50–300 Å on the surface of the resulting structure.
Referring to FIG. 12 , conventional trench sidewall oxidation is carried out on an SOI-type substrate where an amorphous silicon layer is stacked. In this case, the thickness of the oxidation is less than the total thickness of the amorphous silicon layer 153 . Consequently, a surface contacted with oxygen on the stacked amorphous silicon layer is oxidized to form a surface oxide layer 161 having a thickness of about 30–250 Å and a remaining amorphous silicon layer 153 . At the amorphous silicon layer 153 contacted with the patterned SOI layer 123 (i.e., trench sidewall), a crystalline defect of the SOI layer can be cured by a high temperature that is applied to thermal oxidation and solid phase epitaxial growth (SPE) may partially be achieved.
Referring to FIG. 13 , using a CVD technique, a trench oxide layer 171 to fill a trench is stacked on the surface oxide layer 161 . Before forming the trench oxide layer 171 , a thin silicon nitride liner may optionally be stacked (not shown). Annealing is carried out at a temperature of about 750–1150° C. for an hour, and may be followed by another annealing for densifying the trench oxide layer 171 and lowering a wet etching rate. Preferably, the annealing is carried out in a nitrogen ambient. SPE is achieved at the remaining silicon layer 153 of a part contacted with an SOI layer during the one annealing, forming an expanded SOI pattern 123 ′. Meanwhile, a non-SPE part will be an oxide layer in the following process. Therefore, insulation problems caused by any remaining amorphous silicon layer in that region is avoided.
Referring to FIG. 14 , excess trench oxide layer is removed with chemical mechanical polishing (CMP) so as to leave a device isolation layer 173 filling a trench. Then, the silicon nitride layer serving as an etch-stop layer and the pad oxide layer may then be removed as desired.
Sixth Method
Referring to FIG. 15 , there is a silicon nitride layer pattern 117 ′ for forming a trench on an SOI-type substrate where the trench for device isolation are formed by etching an SOI layer. An amorphous silicon layer 151 is then conformally stacked, to a thickness of about 50–300Å, on the surface of the resulting structure.
Referring to FIG. 16 , annealing is carried out on a substrate where an amorphous silicon layer 151 is stacked, at a temperature of about 550–700° C. for an hour, such as in a conventional furnace or an ultra high vacuum (UHV) system without oxygen (such as under nitrogen). The amorphous silicon layer 151 is recrystallized, and SPE is achieved at a part adjacent to an patterned SOI layer 123 owing to the influence of the single crystalline structure of the patterned SOI layer 123 . As a result, an expanded patterned SOI layer 123 ′ is formed.
Referring to FIG. 17 , a sidewall oxidation is then performed to form a surface oxide layer 161 . A trench oxide layer 171 is stacked to fill a trench. Similar to a conventional trench device isolation process, annealing to the trench oxide layer 171 usually follows. A portion of the original amorphous silicon layer of FIG. 16 remains unoxidized and is identified as a remaining silicon layer 153 .
Referring to FIG. 18 , the trench oxide layer 171 is removed over an patterned SOI layer 123 ′ that is an active region, by a planarization etching process using a CMP technique. Only a device isolation layer 173 remains thereof. Then, the silicon nitride layer serving as an etching mask in trench patterning and the pad oxide layer are removed. Before stacking a trench oxide layer, a silicon nitride liner (not shown) may conformally be stacked.
In an annealing process for SPE a crystalline defect of an SOI layer is cured. Therefore, it is often desirable to forgo separate sidewall thermal oxidation. A silicon layer, particularly a remaining silicon layer 153 on a trench bottom, may remain because thermal oxidation is not carried out. But the remaining silicon layer 153 is oxidized in the subsequent oxidation, so that insulation problems caused thereby are avoided.
It is to be understood that all physical quantities disclosed herein, unless explicitly indicated otherwise, are not to be construed as exactly equal to the quantity disclosed, but rather about equal to the quantity disclosed. Further, the mere absence of a qualifier such as “about” or the like, is not to be construed as an explicit indication that any such disclosed physical quantity is an exact quantity, irrespective of whether such qualifiers are used with respect to any other physical quantities disclosed herein.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration only, and such illustrations and embodiments as have been disclosed herein are not to be construed as limiting to the claims. | Disclosed herein are various methods for preventing bending of a patterned SOI layer during trench sidewall oxidation, the methods comprising providing a patterned SOI layer having at least one trench, said patterned SOI layer disposed upon an underlying buried silicon oxide layer; and blocking diffusion of oxygen between said patterned SOI and buried silicon oxide layer. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a new and distinctive cultivar of Gazania rigens hybrid and referred to commercially by the cultivar name `Moorpark Yellow`. Gazania rigens `Moorpark Yellow` was developed by controlled breeding using breeding plant #51-2 as the seed parent and breeding plant #46B-4 as the pollen parent.
BRIEF DESCRIPTION OF THE INVENTION
Gazania rigens `Moorpark Yellow` is a perennial trailing groundcover with outstanding vigor, hardiness, green leaves and numerous large, showy yellow flowers with a black band that bloom from February through December in southern California. Its very large flowers that open early in the morning combined with its excellent vigor are believed to be a substantial step forward and an important advantage for Gazania rigens `Moorpark Yellow` as compared to all other yellow flowering trailing Gazania groundcovers.
DESCRIPTION OF THE DRAWING
The accompanying color photograph, forming a part of this disclosure, was taken in the summer of 1991 in Somis, Calif., and shows a close-up of Gazania rigens `Moorpark Yellow` growing in a 5 gallon can; the view more or less straight down into the plants. The photograph shows the typical flower and foliage form and color as true as is reasonably possible in this type of color photograph.
Comparison of Gazania rigens `Moorpark Yellow` with Other Commercial Yellow Gazania Groundcovers with Green Leaves
The primary distinguishing features of the Gazania rigens `Moorpark Yellow` are its large yellow flowers with black bands and its vigorous growth. To the inventor's knowledge there are only two other yellow flowering Gazania groundcovers with green leaves and yellow flowers with black bands. These other Gazanias are Gazania rigens `Sunrise` and Gazania rigens `Mitsuwa Super Clump`, illustrated in U.S. Plant Pat. No. 5,795 issued Nov. 4, 1986. In comparison to Gazania rigens `Sunrise`, Gazania rigens `Moorpark Yellow` has much more vigor, much larger, flatter flowers which open earlier, larger leaves, greater spread and height and is more frost hardy.
In comparison to Gazania rigens `Mitsuwa Super Clump`, illustrated in U.S. Plant Pat. No. 5,795 issued Nov. 4, 1986, Gazania rigens `Moorpark Yellow` has larger, flatter, darker flowers which open earlier, bigger leaves and a growth habit which is trailing rather than clumping.
Compared to Gazania rigens `Mitsuwa Yellow`, the most commonly planted Gazanias groundcover in California, Gazania rigens `Moorpark Yellow` has larger flowers with a golden color and a black ring around the flower center. They both trail vigorously.
DETAILED DESCRIPTION
The following is a detailed description of Gazania rigens `Moorpark Yellow` based on plants produced under commercial practices outdoors at Mitsuwa Nursery, Moorpark, Calif. Color references are made to The Royal Horticultural Society Colour Chart, except where the context indicates a term having its ordinary dictionary meaning.
Parentage: A controlled breeding cross with Gazania breeding plant #51-2 as the seed parent and Gazania breeding plant #46B-4 as the pollen parent.
Plant form: Plants are vigorous growing trailing groundcover.
Habit of growth: Plants are decumbent, spread rapidly to approximately 11/2 meter in diameter. Plants form a dense carpet to approximately 17 cm in height.
Foliage: Foliage is a medium green with alternate leaves and clasping petioles.
1. Size.--Mature leaves are approximately 141/2 cm in length.
2. Shape.--Leaves vary from simple oblanceolate (to 17 mm in width) to pinnately six lobed (to 25 mm in width).
3. Texture.--Leaves are glabrous above and tomentose below.
4. Margin.--Serrulate.
5. Color.--Topside -- 147 A. Underside -- 155 D.
Flowering description:
1. General.--The flowers are a deep yellow with a black band or ring around the flower center at the base.
2. Habit.--The flower heads arise from leaf axils on peduncles to approximately 13 cm in length.
3. Season of bloom.--Varies with the climate. In Moorpark, Calif., heavy bloom occurs from approximately late February to early December.
4. Flower parts.--a. Flower heads measure to approximate 85 mm across. The disc flowers in the center measure approximately 15 mm across. b. Ray petals measure up to approximately 52 mm in length and up to approximately 13 mm in width. The base of each ray petal has a black spot measuring approximately 4 mm wide, and which may or may not have a small white dot in the middle. These black spots form the band or ring at the flower base. The underside of each ray petal has a longitudinal lighter yellow section down the center between the two main veins and a dark blue-black spot at the base. c. There are 18 to 20 ray petals per flower head.
5. Color.--Ray petal, topside -- 14B. Ray petal, bottomside, edges -- 14A. Ray petal, bottomside, center -- 11C.
Disease resistance: No disease problems have been found in Gazania rigens `Moorpark Yellow`. In the fields at Mitsuwa Nursery, Gazania rigens `Moorpark Yellow` has shown good disease tolerance.
Hardiness: Gazania rigens `Moorpark Yellow` has gone through two frost tests at Mitsuwa Nursery to qualify for patentability. It has proven to be more frost tolerant than Gazania rigens `Mitsuwa Yellow`, the most commonly planted yellow training Gazania in California.
Propagation: Asexual reproduction of the new and distinct variety has been accomplished by stem cuttings. The resulting plants have shown that the above-mentioned unique features of this new Gazania are stable and reproduce true to type in each of the successive propagations. Gazania rigens `Moorpark Yellow` roots in about 2-3 weeks in warm conditions. | A new and distinct Gazania plant having large yellow banded flowers and green foliage and characterized by its vigorous growth and trailing habit. | 0 |
[0001] The following specification particularly describes the nature of the invention and the manner in which it has to be performed;
FIELD OF THE INVENTION
[0002] The present invention relates to novel heterocyclic derivatives of the general formula (I), their pharmaceutically acceptable salts and compositions, their analogs, their tautomeric forms, and their stereoisomers. The present invention more particularly provides novel compounds of the general formula (I).
[0000]
[0003] The present invention also relates to a process for the preparation of the above said novel compounds, their pharmaceutically acceptable salts and compositions, their analogs, their tautomeric forms, and their stereoisomers.
[0004] The compounds of the present invention are effective in lowering blood glucose, serum insulin, free fatty acids, cholesterol and triglyceride levels and are useful in the treatment and/or prophylaxis of type II diabetes. These compounds are effective in treatment of obesity, inflammation, autoimmune diseases such as multiple sclerosis and rheumatoid arthritis. Surprisingly, these compounds increase the leptin level and have no liver, toxicity.
[0005] Furthermore, the compounds of the present invention are useful for the treatment of disorders associated with insulin resistance, such as polycystic ovary syndrome, as well as hyperlipidemia, coronary artery disease, peripheral vascular disease, and for the treatment of inflammation and immunological diseases, particularly those mediated by cytokines such as TNF-α, IL-1, IL-6, IL-1β and cyclooxygenases such as COX-2.
BACKGROUND OF THE INVENTION
[0006] The causes of type I and II diabetes are not yet clear, although both genetics and environment seem to be the factors. Type I diabetes is an autonomic immune disease and patient must take insulin to survive. Type II diabetes is the more common form, it is a metabolic disorder resulting from the body's inability to make a sufficient amount of insulin or to properly use the insulin that is produced. Insulin secretion and insulin resistance are considered to be the major defects; however, the precise genetic factors involved in the mechanism remain unknown.
[0007] Patients with diabetes usually have one or more of the following defects:
[0008] Less production of insulin by the pancreas;
[0009] Over secretion of glucose by the liver;
[0010] Independence of the glucose uptake by the skeletal muscles;
[0011] Defects in glucose transporters, desensitization of insulin receptors; and
[0012] Defects in the metabolic breakdown of polysaccharides.
[0013] Other than the parenteral or subcutaneous administration of insulin, there are about four classes of oral hypoglycemic agents used i.e. sulfonylureas, biguanides, alpha glucosidase inhibitors and thiazolidinediones. Each of the current agents available for use in treatment of diabetes has certain disadvantages. Accordingly, there is a continuing interest in the identification and development of new agents, which can be orally administered, for use in the treatment of diabetes.
[0014] The thiazolidinedione class listed above has gained more widespread use in the recent years for the treatment of type II diabetes, exhibiting particular usefulness as insulin sensitizers to combat “insulin resistance”, a condition in which the patient becomes less responsive to the effects of insulin. However there is a continuing need for nontoxic, more widely effective insulin sensitizers. In our continuous efforts to explore new compounds having antidiabetic activity, is our present invention where we propose to synthesize new compounds containing rhodanine, rhodanine-3-aceticacid, thiazolidinone, oxindole, benzathiazolone, morpholone, morpholine, and the oxazolidinone system and also study them for anti-diabetic activity by taking thiazolidinone as a comparator.
[0015] Recent advances in the scientific understanding of the mediators involved in acute and chronic inflammatory diseases and cancer have led to new strategies in the search for effective therapeutics. Traditional approaches include direct target intervention such as the use of specific antibodies, receptor antagonists, or enzyme inhibitors. Recent breakthroughs in the elucidation of regulatory mechanisms involved in the transcription and translation of a variety of mediators have led to an increased interest in the therapeutic approaches directed at the level of gene transcription.
[0016] As indicated above, the present invention is also concerned with the treatment of immunological diseases or inflammation, notably such diseases as are mediated by cytokines or cyclooxygenase. The principal elements of the immune system are macrophages or antigen-presenting cells, T cells and B cells. The role of other immune cells such as NK cells, basophils, mast cells and dendritic cells are known, but their role in primary immunologic disorders is uncertain. Macrophages are important mediators of both inflammation and provide the necessary “help” for T cell stimulation and proliferation. Most importantly macrophages make IL 1, IL 12 and TNF-α all of which are potent pro-inflammatory molecules and also provide help for T cells. In addition, activation of macrophages results in the induction of enzymes, such as cyclooxygenase II (COX-2), inducible nitric oxide synthase (iNOS) and production of free radicals capable of damaging normal cells. Many factors activate macrophages, including bacterial products, superantigens and interferon gamma (IFNγ). It is believed that phosphotyrosine kinases (PTKs) and other undefined cellular kinases are involved in the activation process.
[0017] Cytokines are molecules secreted by immune cells that are important in mediating immune responses. Cytokine production may lead to the secretion of other cytokines, altered cellular function, cell division or differentiation. Inflammation is the normal response of the body to injury or infection. However, in inflammatory diseases such as rheumatoid arthritis, pathologic inflammatory processes can lead to morbidity and mortality. The cytokine tumor necrosis factor-alpha (TNF-α) plays a central role in the inflammatory response and has been targeted as a point of intervention in inflammatory disease. TNF-α is a polypeptide hormone released by activated macrophages and other cells. At low concentrations, TNF-α participates in the protective inflammatory response by activating leukocytes and promoting their migration to extravascular sites of inflammation (Moser et al., J Clin Invest, 83, 444-55, 1989). At higher concentrations, TNF-α can act as a potent pyrogen and induce the production of other pro-inflammatory cytokines (Haworth et al., Eur J Immunol, 21, 2575-79, 1991; Brennan et al., Lancet, 2, 244-7, 1989). TNF-α also stimulates the synthesis of acute-phase proteins. In rheumatoid arthritis, a chronic and progressive inflammatory disease affecting about 1% of the adult U.S. population, TNF-α mediates the cytokine cascade that leads to joint damage and destruction (Arend et al., Arthritis Rheum, 38, 151-60, 1995). Inhibitors of TNF-α, including soluble TNF receptors (etanercept) (Goldenberg, Clin Ther, 21, 75-87, 1999) and anti-TNF-α antibody (infliximab) (Luong et al., Ann Pharmacother, 34, 743-60, 2000), have recently been approved by the U.S. FDA as agents for the treatment of rheumatoid arthritis. Elevated levels of TNF-α have also been implicated in many other disorders and disease conditions, including cachexia, septic shock syndrome, osteoarthritis, inflammatory bowel disease such as Crohn's disease and ulcerative colitis etc. It can be seen that inhibitors of TNF-α are potentially useful in the treatment of a wide variety of diseases. Compounds that inhibit TNF-α have been described in several patents.
[0018] Excessive production of IL-6 is implicated in several disease states; it is highly desirable to develop compounds that inhibit IL-6 secretion. Compounds that inhibit IL-6 have been described in the U.S. Pat. Nos. 6,004,813; 5,527,546 and 5,166,137.
[0019] The cytokine IL-1β also participates in the inflammatory response. It stimulates thymocyte proliferation, fibroblast growth factor activity, and the release of prostaglandin from synovial cells. Elevated or unregulated levels of the cytokine IL-1β have been associated with a number of inflammatory diseases and other disease states, including but not limited to adult respiratory distress syndrome, allergy, Alzheimer's disease etc. Since the overproduction of IL-1β is associated with numerous disease conditions, it is desirable to develop compounds that inhibit the production or activity of IL-1β.
[0020] It will be appreciated from the foregoing facts that, while there have been extensive prior efforts to provide compounds for inhibiting, for example, TNF-α, IL-1, IL-6, COX-2 or other agents considered responsible for immune response, inflammation or inflammatory diseases, e.g. arthritis, there still remains a need for new and improved compounds for effectively treating or inhibiting such diseases. With an objective of providing compounds, which are effective for such treatments as well as for the treatment of, for example, insulin resistance, hyperlipidemia, obesity, inflammation, multiple sclerosis and arthritis, we have continued our research to develop new thiazoldinediones along with other heterocyclic analogs.
[0000] Few Prior Art References, which Disclose the Closest Compounds, are Given Here:
[0021] i) WO 01/02377 discloses compounds of the formula (Ia) as telomerase inhibitors
[0000]
[0000] wherein R′ 1 and R′ 2 represents hydrogen, alkyl etc., X represents oxygen or sulfur; ---- is a single or double bond; L represents oxygen, nitrogen, sulfur; R′ 3 represents hydrogen, alkyl, aryl etc., R′ 4 represents hydrogen, alkyl, aryl etc., A′ represents aryl.
[0022] An example of these compounds is shown in formula (IIb)
[0000]
[0023] ii) EP 1148054 discloses compounds of formula (IIc)
[0000]
[0000] wherein R 1 ″, R 2 ″, R 3 ″, R 5 ″, R 6 ″, represent hydrogen, alkyl etc., X′ represents methylene thiazolidin-2,4-dione, methylene oxazolidin-2,4-dione etc., W′ represents oxygen, sulfur; R 4 ″ represents hydrogen, alkyl substituted with zero to three substituents etc.
[0024] An example of these compounds is shown in formula (IId)
[0000]
[0025] iii) U.S. Pat. No. 6,331,633 discloses compounds of formula (IIe)
[0000]
[0000] wherein Z is
[0000]
[0000] wherein n, m, q and r are independently integers from zero to 4; p and s are independently integers from zero to 5; a, b and c are double bonds which may be present or absent; R, R′ and R″ are independently H, C 1 -C 20 linear or branched alkyl, C 2 -C 20 linear or branched alkenyl, —CO 2 H, —CO 2 R′″, —NH 2 , —NHR′″, —NR 2 ′″, —OH, —OR′″, halo, substituted C 1 -C 20 linear or branched alkyl or substituted C 2 -C 20 linear or branched alkenyl, wherein R′″ is C 1 -C 20 linear or branched alkyl or linear or branched alkenyl; A, A′ and A″ are independently H, C 1 -C 20 acyl amino; C 1 -C 20 acyloxy; C 1 -C 20 alkanoyl; C 1 -C 20 alkoxycarbonyl; C 1 -C 20 alkoxy; C 1 -C 20 alkylamino; C 1 -C 20 alkylcarboxylamino; carboxyl; cyano; halo; hydroxy; B, B′ and B″ are independently H; C 1 -C 20 acylamino; C 1 -C 20 acyloxy; C 1 -C 20 alkanoyl; etc., X, X′ are independently —NH, —NR′″, O or S.
[0026] An example of these compounds is shown in formula (IIf)
[0000]
[0027] iv) Tetrahedron asymmetry 14, 2003, 2619-2623 discloses the two step synthesis of enantiopure tert-butyl (1S)-2-hydroxy-1-(4-benzyloxybenzyl)ethylcarbamate from N-Boc-L-tyrosine(1a).
[0000]
OBJECTIVE OF THE INVENTION
[0028] With an objective of developing novel compounds for lowering the blood glucose, free fatty acids, cholesterol and triglyceride levels in type II diabetes and to treat autoimmune diseases such as multiple sclerosis and rheumatoid arthritis, we focused our research to develop new compounds effective in the treatment of the above mentioned diseases, and efforts in this direction have led to compounds having the general formula (I).
[0029] The main objective of the present invention is therefore, to provide heterocyclic derivatives of the general formula (I), their pharmaceutically acceptable salts and compositions, their analogs, their tautomeric forms, and their stereoisomers that are useful for the treatment of disorders associated with insulin resistance, such as polycystic ovary syndrome, as well as hyperlipidemia, coronary artery disease, peripheral vascular disease, and are also useful for the treatment of inflammation and immunological diseases, particularly those mediated by cytokines such as TNF-α, IL-1, IL-6, IL-1β and cyclooxygenases such as COX-2. Another objective of the present invention is to provide novel heterocyclic derivatives of the general formula (I), their pharmaceutically acceptable salts and compositions, their analogs, their tautomeric forms, and their stereoisomers having enhanced activities, without toxic effects or with reduced toxic effects. Yet another objective of the present invention is to provide a process for the preparation of the novel heterocyclic derivatives of the general formula (I), their pharmaceutically acceptable salts and compositions, their analogs, their tautomeric forms, and their stereoisomers.
SUMMARY OF THE INVENTION
[0030] The present invention, relates to novel heterocyclic derivatives of the general formula (I)
[0000]
[0000] their pharmaceutically acceptable salts and compositions, their analogs, their tautomeric forms, and their stereoisomers; wherein ---- represents an optional bond; R represents CH 2 , C═O; W represents O or S; X represents C, CH or N; Y represents NR 5 , S or O, wherein R 5 represents hydrogen, substituted or unsubstituted alkyl, alkenyl, —CH 2 COOR′, aryl, or a counter ion; wherein R′ represents H or an alkyl group; Z represents CR 6 or S; R 1 represents ═O, ═S or together with R 6 forms a fused 5 or 6 membered aromatic or heteroaromatic ring system containing carbon atoms or 1 or 2 heteroatoms selected from O, S or N; R 2 and R 3 may be same or different and independently represent hydrogen, halogen, hydroxy, nitro, cyano, formyl, amino, alkyl, haloalkyl, alkoxy group; R 4 represents H, COR 7 , substituted or unsubstituted groups selected from alkyl, alkenyl, aryl, aryloxy, alkoxy, heteroaryl or heterocyclyl; wherein R 7 represents H, substituted or unsubstituted groups selected from alkyl, alkenyl, aryl, aryloxy, alkoxy or aralkoxy.
DETAILED DESCRIPTION OF THE INVENTION
[0031] Suitable groups represented by R represent CH 2 , C═O;
[0032] R 1 is selected from ═O, ═S; or together with R 6 forms a fused 5 or 6 membered aromatic or heteroaromatic ring system containing carbon atoms or 1 or 2 heteroatoms selected form O, S or N such as phenyl, naphthyl, furyl, pyrrolyl, pyridyl and the like.
[0033] Suitable groups represented by R 2 and R 3 , are selected from hydrogen, halogens such as fluorine, chlorine, bromine or iodine; hydroxy, nitro, cyano, formyl, amino, substituted or unsubstituted linear or branched (C 1 -C 4 ) allyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, and the like; haloalkyl groups selected from alkyl group substituted by one, two, three or four halogen atoms such as chloromethyl, chloroethyl, trifluoromethyl, trifluoroethyl, dichloromethyl, dichloroethyl and the like; substituted or unsubstituted (C 1 -C 4 ) alkoxy group such as methoxy, ethoxy, propoxy, butoxy and the like.
[0034] Suitable groups represented by R 4 are selected from hydrogen, substituted or unsubstituted groups selected from (C 1 -C 4 ) alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl and the like; substituted or unsubstituted linear or branched (C 2 -C 7 ) alkenyl groups such as ethenyl, propenyl, butenyl and the like; aryl groups such as phenyl, naphthyl and the like, the aryl group may be substituted; aryloxy groups such as phenoxy, napthoxy and the like, substituted or unsubstituted linear or branched (C 2 -C 4 ) alkoxy groups such as methoxy, ethoxy, propoxy, n-butoxy, and the like; heteroaryl groups such as pyridyl, thienyl, furyl, pyrrolyl, oxazolyl, thiazolyl, imidazolyl, oxadiazolyl, triazolyl, tetrazolyl, pyrimidinyl, pyrazinyl, indolyl, indolinyl, benzothiazolyl, and the like, which may be substituted; heterocyclyl groups such as pyrrolidinyl, thiazolidinyl, oxazolidinyl, morpholinyl, thiomorpholinyl, piperidinyl, piperazinyl, and the like, which may be substituted, COR 7 , wherein R 7 represents H; substituted or unsubstituted groups selected from (C 1 -C 4 ) alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl and the like; substituted or unsubstituted linear or branched (C 2 -C 7 ) alkenyl groups such as ethenyl, propenyl, butenyl and the like; aryl groups such as phenyl, naphthyl and the like, the aryl group may be substituted; aryloxy groups such as phenoxy, napthoxy and the like; substituted or unsubstituted linear or branched (C 2 -C 20 ) alkoxy groups such as methoxy, ethoxy, propoxy, n-butoxy, isobutoxy, t-butoxy and the like;
[0035] Pharmaceutically acceptable salts of the present invention include base addition salts such as alkali metal salts like Li, Na, and K salts, alkaline earth metal salts like Ca and Mg salts, salts of organic bases such as diethanolamine, α-phenylethylamine, benzylamine, piperidine, morpholine, pyridine, hydroxyethylpyrrolidine, hydroxyethylpiperidine, choline and the like, ammonium or substituted ammonium salts, aluminum salts. Salts also include amino acid salts such as glycine, alanine, cystine, cysteine, lysine, arginine, phenylalanine, guanidine etc. Salts may include acid addition salts where appropriate which are sulphates, nitrates, phosphates, perchlorates, borates, hydrohalides, acetates, tartrates, maleates, citrates, succinates, palmoates, methanesulphonates, tosylates, benzoates, salicylates, hydroxynaphthoates, benzenesulfonates, ascorbates, glycerophosphates, ketoglutarates and the like. Pharmaceutically acceptable solvates may be hydrates or comprising of other solvents of crystallization such as alcohols.
[0036] The protecting groups used in the invention are conventional protecting groups such as t-butoxycarbonyl(t-Boc), trityl, trifluoroacetyl, benzyloxy, benzyloxy carbonyl(Cbz) and the like and deprotection can be done by conventional methods.
Particularly Useful Compounds According to the Invention Include:
[0000]
5-(4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
5-(4-{4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)morpholin-3-one;
5-(-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]acetic acid;
5-(4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-dihydro-2H-indol-2-one;
5-(3-fluoro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
5-(3-fluoro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl)acetic acid;
5-(3-chloro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
5-(4-{2-chloro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)morpholin-3-one;
5-(3-chloro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-dihydro-2H-indol-2-one;
5-(2-chloro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]acetic acid;
5-(4-{3-chloro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)morpholin-3-one;
5-(2-chloro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
5-[4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}-3-(trifluoromethyl) benzylidene]-1,3-thiazolidine-2,4-dione;
5-(2-chloro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-dihydro-2H-indol-2-one;
5-(3-fluoro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-dihydro-2H-indol-2-one;
5-(4-{2-fluoro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)morpholin-3-one;
5-(3-(trifluoromethyl)-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-dihydro-2H-indol-2-one;
5-(4-{4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]-2-(trifluoromethyl)phenoxy}benzyl)morpholin-3-one;
5-(4-{4-[(4-methyl-5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
4-methyl-5-(4-{4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene) methyl]phenoxy}benzyl)morpholin-3-one;
5-(4-{2-methoxy-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)morpholin-3-one;
5-(3-trifluoromethyl-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]acetic acid;
5-(4-{3-fluoro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)morpholin-3-one;
5-(3-fluoro-4-{4-[(4-methyl-5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
5-(2-fluoro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-dihydro-2H-indol-2-one;
5-(2-fluoro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]acetic acid;
5-(3-fluoro-4-{4-[(4-methyl-5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl]acetic acid;
5-(4-{2-chloro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)-4-methylmorpholin-3-one;
5-(2-chloro-4-{4-[(4-methyl-5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
5-(4-{3-chloro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)-4-methylmorpholin-3-one;
5-(3-chloro-4-{4-[(4-methyl-5-oxomorpholin-3-yl)methyl]phenoxy}benzylidene)-1,3-thiazolidine-2,4-dione;
5-(4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzyl)-1,3-dihydro-2H-indol-2-one;
5-(3-fluoro-4-{4-[(5-oxomorpholin-3-yl)methyl]phenoxy}benzyl)-1,3-thiazolidine-2,4-dione;
5-(4-{2-chloro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-yl)methyl]phenoxy}benzyl)morpholin-3-one.
[0071] Preferred salts for the list of compounds given above are hydrochloride, hydrobromide, sodium, potassium or magnesium.
[0072] In another aspect the invention provides novel pharmaceutical compositions comprising the heterocyclic derivatives of the formula (I) as set out above. The said compositions may comprise the heterocyclic derivatives as the active ingredient together with the pharmaceutically acceptable carrier, diluent or excipient. The composition may be prepared by processes known in the art and may be in the form of a tablet, capsule, powder, syrup, solution or suspension. The amount of the active ingredient in the composition may be less than 60% by weight.
[0073] According to another feature of the present invention, there is provided a process for the preparation of the compounds of formula (I) wherein ---- represents a bond, and all the other symbols are as defined earlier, as shown in the scheme:
Scheme:
[0000]
a) Deprotection of the compound of formula (1a) to (2a) and further alkylation of the compound of formula (2a) gave the compound of formula (3a). The compound of formula (1 a) is prepared according to the procedure described in Tetrahedron asymmetry 14, 2619-2623 (2003).
[0000]
b) Cyclization of the compound of formula (3a) gave (4a); which is further debenzylated to give the compound of formula (5a) wherein all other symbols are as defined earlier. Alternatively the compound of formula (4a) wherein R 4 =alkyl can be prepared by alkylation of compound of formula (4a) wherein R 4 =hydrogen by conventional methods.
[0000]
b) Optional reduction of the compound of formula (5a) gave the compound of formula (6a) wherein all the symbols are as defined earlier.
[0000]
c) Condensation of the compound of formula (6a) with a compound of formula (7a) gave the compound of formula (8a) wherein all the symbols are as defined earlier.
[0000]
[0000] d) Reaction of the compound of formula (8a) with a compound of the formula (9a) gave the compound of formula (10a) wherein all the symbols are as defined earlier.
[0000]
f) Alternatively deprotection or reduction of the compound of formula (10a), wherein R 4 may be the protecting group as defined earlier, produces the compound of formula (I). The order of deprotection and reduction can be changed or reversed.
[0000]
The Reactions Described in the Processes Outlined Above are Performed by Using the Methods Described Herein:
[0079] The deprotection of the compound of formula (1a) to compound of formula (2a) may be carried out using acids such as HCl, sulfuric acid, acetic acid in the presence of solvents such as dichloromethane, ethyl acetate, water and the like or a mixture thereof at a temperature in the range of −10° C. to 50° C.
[0080] The reaction of the compound of formula (2a) with chloro acetylchloride is carried out in the presence of solvents such as dichloromethane, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, DME and the like or a mixtures of solvents may be used to produce the compound of formula (3a). The reaction may be carried out in an inert atmosphere, and may be effected in the presence of a base such as triethylamine, K 2 CO 3 , Na 2 CO 3 , NaH or mixtures thereof. The reaction temperature may range from 0° C. to 50° C., preferably in the range of 0° C. to 10° C. The duration of the reaction may range from 1 to 12 hours, preferably from 2 to 6 hours.
[0081] Cyclisation of the compound of formula (3a) is carried out in the presence of a base such as potassium t-butoxide, NaH and in the presence of a solvent such as t-butanol, isopropanol, toluene, methoxyethanol or mixtures thereof to yield a compound of formula (4a). The reaction temperature may range from 0° C. to 50° C., preferably in the range of 10° C. to 40° C. The duration of the reaction may range from 1 to 12 hours, preferably from 2 to 6 hours.
[0082] Debenzylation of the compound of formula (4a) to the compound of formula (5a) may be carried out in the presence of gaseous hydrogen and a catalyst such as Pd/C, Rh/C, Pt/C, Raney Nickel, and the like. Alternatively mixtures of catalysts may be used. The reaction may be conducted in the presence of solvents such as methanol, dichloromethane, dioxane, acetic acid, ethyl acetate and the like or even mixtures of solvents may be used. A pressure between atmospheric pressure to 100 psi may be employed. The catalyst may be 5-10% Pd/C and the amount of catalyst used may range from 50-300% w/w.
[0083] Reduction of the compound (5a) to the compound (6a) may be carried out in the presence of catalyst such as NaBH 4 , LiAlH 4 zinc-mercury amalgam, hydrazine and the like. The reaction may be conducted in the presence of solvents such as methanol, dichloromethane, dioxane, acetic acid, ethyl acetate and the like or even a mixture of solvents may be used.
[0084] The reaction of the compound of formula (6a) with the compound of formula (7a) is carried out in the presence of solvents such as tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, DME and the like or a mixture of solvents may also be used, to produce the compound of formula (8a). The reaction may be carried out in an inert atmosphere and may be effected in the presence of a base such as K 2 CO 3 , Na 2 CO 3 , NaH or mixtures thereof. The reaction temperature may range from 60° C. to 150° C., preferably in the range of 80° C. to 100. ° C. The duration of the reaction may range from 1 to 24 hours, preferably from 2 to 6 hours.
[0085] The reaction of the compound of the formula (8a) with a compound of formula (9a) is carried out in the presence of a base using solvents such as toluene, methoxyethanol or mixtures thereof to yield a compound of formula (10a). The reaction temperature may range from 60° C. to 150° C. Suitable catalyst such as piperidinium acetate or benzoate, sodium acetate or a mixture of catalysts may also be employed. The water produced in the reaction may be removed by using Dean Stark water separator or by using water-absorbing agents like molecular sieves.
[0086] The deprotection of formula (10a) to yield a compound of formula (I) may be carried out using acids such as HCl, sulfuric acid, acetic acid in the presence of solvents such as dichloromethane, ethyl acetate, water and the like or a mixture thereof at a temperature in the range of −10° C. to 50° C.
[0087] In another embodiment of the present invention, there is provided a process for the preparation of compounds of formula (1), by reducing the penultimate step of formula (1) wherein --- represents bond The reduction step is not required when -------- represents no bond and all other symbols are as defined earlier. The reduction may be carried out in the presence of gaseous hydrogen and a catalyst such as Pd/C, Rh/C, Pt/C, Raney Nickel, and the like. A mixture of catalysts may also be used. The reaction may be conducted in the presence of solvents such as methanol, dichloromethane, dioxane, acetic acid, ethyl acetate and the like. Mixtures of solvents may also be used. A pressure between atmospheric pressure to 100 psi may be employed. The catalyst may be 5-10% Pd/C and the amount of catalyst used may range from 50-300% w/w. It may also be noted that the order of deprotection and reduction can be changed or reversed.
[0088] It is appreciated that in any of the above-mentioned reactions, any reactive group in the substrate molecule may be protected according to the conventional chemical practice. Suitable protecting groups in any of the above-mentioned reactions are those used conventionally in the art. The methods of formation and removal of such protecting groups are those conventional methods appropriate to the molecule being protected. More specifically the protecting groups P used particularly in the present invention are conventional protecting groups such as t-butoxy carbonyl(t-Boc), trityl, trifluoroacetyl, benzyloxy, benzyloxy carbonyl(Cbz) and the like and deprotection can be done by conventional methods.
[0089] The pharmaceutically acceptable salts are prepared by reacting the compound of formula (I) with 1 to 4 equivalents of a base such as sodium hydroxide, sodium methoxide, sodium hydride, potassium t-butoxide, calcium hydroxide, magnesium hydroxide and the like, in solvents like ether, THF, methanol, t-butanol, dioxane, isopropanol, ethanol etc. Mixtures of solvents may also be used. Organic bases like lysine, arginine, diethanolamine, choline, guanidine and their derivatives etc. may also be used. Alternatively, acid addition salts are prepared by treatment with acids such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, p-toluenesulfonic acid, methanesulfonic acid, acetic acid, citric acid, maleic acid, salicylic acid, hydroxynaphthoic acid, ascorbic acid, palmitic acid, succinic acid, benzoic acid, benzene sulfonic acid, tartaric acid and the like in solvents like ethyl acetate, ether, alcohols, acetone, THF, dioxane etc. Mixture of solvents may also be used.
[0090] The invention is explained in details in the examples given below which are provided by the way of illustration only and therefore should not be construed to limit the scope of the invention.
EXAMPLE 1
Synthesis of 5-[4-(4-{[5-oxomorpholin-3-yl]methyl}phenoxy)benzylidene]-1,3-thiazolidine-2,4-dione
[0091]
Step I
Synthesis of 2-amino-3-[4-(benzyloxy)phenyl]propan-1-ol hydrochloride
[0092]
[0093] Dry HCl gas was bubbled into a solution of tert-butyl-2-hydroxy-1-(4-benzyloxybenzyl)ethylcarbamate (4g, 11.20 mmol) in dichloromethane (50 ml) at 0-5° C. for two hours. After completion of the reaction, the excess of HCl gas was removed by nitrogen gas bubbling and the white solid thus obtained was filtered and dried to yield 2-amino-3-[4-(benzyloxy)phenyl]propan-1-ol hydrochloride (2.35 g). 1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.46 (q, 1H), 2.73 (dd, 1H), 3.06 (m, 1H), 3.35 (m, 1H), 3.63 (dd, 1H) 5.04 (s, 2H), 6.91 (d, 2H), 7.11 (d, 2H), 7.40 (m, 5H); MS (ESI, +ve) m/z M+1 259.4
Step II
Synthesis of N-{1-[4-(benzyloxy)benzyl]-2-hydroxyethyl}-2-chloroacetamide
[0094]
[0095] To the suspension of 2-amino-3-[4-(benzyloxy)phenyl]propan-1-ol hydrochloride (1.0 g, 3.40 mmol) in dichloromethane (30 ml) was added triethylamine (1.42 ml, 10.22 mmol) at 0-5° C. followed by chloro acetyl chloride (0.325 ml, 4.04 mmol). After completion of reaction the reaction mixture was washed with 5% aq HCl solution, followed by brine solution, dried over sodium sulfate and concentrated to afford the title compound (0.820 g). 1 HNMR [CDCl 3 400 MHz]: δ (ppm): 2.85 (m, 2H), 3.63 (dd, 1H), 3.69 (dd, 1H), 4.01 (d, 2E), 4.12 (m, 1H) 5.04 (s, 2H), 6.85 (d, 1H), 6.93 (d, 2H), 7.15 (d, 2H), 7.40 (m, 5H); MS (ESI, +ve) m/z (relative intensity, %): 334.1 (M + , 100), 336.1 (M + , 33).
Step III
Synthesis of 5-[4-(benzyloxy)benzyl]morpholin-3-one
[0096]
[0097] A solution of N-{1-[4-(benzyloxy)benzyl]-2-hydroxyethyl}-2-chloroacetamide (0.8 g, 2.40 mmol) in 30 ml of t-butanol was added to a suspension of potassium t-butoxide (0.4 g, 3.60 mmol) in t-butanol (20 ml) in 10 minutes at 30° C. and stirred for four hours. After completion of reaction, the reaction mixture was quenched with 5% aq. HCl solution and concentrated. The sticky mass thus obtained was neutralized by 5% NaHCO 3 and extracted with ethyl acetate. The organic layer thus obtained was dried over anhydrous sodium sulfate and concentrated to afford the title compound (0.7 g). 1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.62 (m, 1H), 2.84 (dd, 1H), 3.55 (m, 1H), 3.70 (m, 1H), 3.92 (dd, 1H), 4.16 (d, 2H), 5.06 (s, 2H), 5.84 (bs, 1H), 6.94 (d, 2H), 7.11 (d, 2H), 7.42 (m, 5H); MS (ESI, +ve) m/z M+1 298.3
Step IV
Synthesis of 5-(4-hydroxybenzyl)morpholin-3-one
[0098]
[0099] To the solution of 5-[4-(benzyloxy)benzyl]morpholin-3-one (0.7 g, 2.35 mmol) in methanol (100 ml) was added 10% Pd/C (0.100 g). The reaction mixture was hydrogenated at 40 psi for 5-6 hours. The progress of reaction was monitored by TLC. On completion, the solvent was evaporated under reduced pressure to afford the product as an off white solid (0.41 g). 1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.63 (m, 1H), 2.81 (dd, 1H), 3.54 (m, 1H), 3.68 (m, 1H), 3.89 (dd, 1H), 4.16 (d, 2H), 5.86 (bs, 1H), 6.81 (d, 2H), 7.05 (d 2H); MS (ESI, +ve) m/z M+1 208.3
Step V
Synthesis of 4-(4-{[5-oxomorpholin-3-yl]methyl}phenoxy)benzaldehyde
[0100]
[0101] To a suspension of potassium carbonate (1.06 g, 7.68 mmol) in dry DMF (20 ml), was charged 5-(4-hydroxybenzyl)morpholin-3-one (0.4 g, 1.93 mmol), at 30° C. and the reaction mixture was stirred for 15 minutes. Subsequently p-fluorobenzaldehyde (0.239 g, 1.92 mmol) was charged to the reaction mixture, which was warmed to 80° C. and then stirred for 24 hours. The reaction mixture was quenched with water and extracted with ethyl acetate; the combined organic layer was dried over sodium sulfate, concentrated and purified to afford the title compound (0.45 g). 1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.78 (m, 1H), 2.94 (dd, 1H), 3.61 (m, 1H), 3.68 (m, 1H), 3.92 (dd, 1H), 4.20 (d, 2H), 5.99 (bs, 1H), 7.06 (d, 4H), 7.24 (d, 2H), 7.87 (d, 2H), 9.93 (s, 1H); MS (ESI, +ve) m/z M+1 312.1
Step VI
Synthesis of 5-[4-(4-{[5-oxomorpholin-3-yl]methyl}phenoxy)benzylidene]-1,3-thiazolidine-2,4-dione
[0102]
[0103] To a suspension of 4-(4-{[5-oxomorpholin-3-yl]methyl}phenoxy)benzaldehyde (0.2 g, 0.643 mmol) in toluene (40 ml) was charged 2,4-thiazolidinonedione (0.090 g, 0.771 mmol), benzoic acid (0.012 g, 0.095 mmol) and piperidine (0.007 g, 0.083 mmol). The reaction mixture was refluxed at 145° C.-155° C. with continuous removal of water using a dean stark apparatus for 3 hours. The solvent was removed by distillation and the crude product thus obtained was purified to yield the product (0.8 g, (30.4%). 1 HNMR [DMSO-d 6 400MHz] δ (ppm): 2.76 (m, 1H), 2.86 (m, 1H), 3.44 (m, 1H), 3.65 (m, 2H), 3.95 (d, 2H), 7.0 (m, 4H), 7.3 (d, 2H), 7.6 (d, 1H), 7.76 (s, 1H) 8.14 (s, 1H), 12.6 (bs, 1H); MS (ESI, +ve) m/z M+1 411.1
[0000]
The following compounds were prepared according to the procedure give in
the example 1:
Example
Structure
Analytical Data
2
1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.7 (m,1 H), 2.9 (m, 1 H), 3.61 (m, 1 H), 3.75 (m, 1 H),3.94 (dd, 1 H) 4.19 (s, 2 H), 7.05 (m, 4 H), 7.23(d, 2 H), 7.46 (d, 2 H), 7.59 (s, 1 H); MS (ESI,+ve) m/z M+1 427.1
3
1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.8 (m,2 H), 3.61 (m, 1 H), 3.73 (m, 1 H), 3.88 (m, 1 H),4.17 (s, 2 H), 4.85 (s, 2 H) 7.06 (m, 4 H), 7.24(d, 2 H), 7.49 (d, 2 H), 7.75 (s, 1 H); MS (ESI,+ve) m/z M+1 485.2
4
1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.74 (m,1 H), 2.9 (m, 1 H), 3.59 (m, 1 H), 3.77 (m, 1 H),3.94 (dd, 1 H), 4.19 (s, 2 H), 6.11 (s, 1 H), 6.84(d, 1 H), 7.0 (m, 5 H), 7.2 (m, 3 H), 7.52 (d,2 H), 7.84 (s, 1 H), 8.33 (d, 2 H); MS (ESI,+ve) m/z M+1 427.2
5
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.76(m, 1 H), 2.85 (m, 1 H), 3.0 (m, 1 H), 3.62 (m,2 H), 3.94 (d, 2 H), 7.03 (d, 2 H), 7.18 (m, 1 H),7.25 (d, 2 H), 7.39 (d, 1 H), 7.64 (dd, 1 H),7.73 (s, 1 H), 8.12 (s, 1 H); MS (ESI, +ve)m/z M+1 429.2
6
1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.8 (m,2 H), 3.6 (m, 1 H), 3.73 (m, 1 H), 3.8 (dd, 1 H),4.17 (s, 2 H), 4.85 (s, 2 H) 7.0 (m, 3 H), 7.2 (m,3 H), 7.3 (m, 1 H), 7.69 (s, 1 H); MS (ESI, +ve)m/z M+ 503.1
7
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.75(m, 1 H), 2.88 (m, 1 H), 3.44 (m, 1 H), 3.64 (m,2 H), 3.95 (s, 2 H), 7.08 (m, 3 H), 7.26 (d, 2 H), 7.51(d, 1 H), 7.75 (s, 1 H), 7.86 (s, 1 H), 8.13 (s, 1 H),12.5 (bs, 1 H); MS (ESI, +ve) m/z (relativeintensity, %): 445(M + , 100), 447(M + , 33).
8
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.75(m, 1 H), 2.88 (m, 1 H), 3.44 (m, 1 H), 3.65 (m,2 H), 3.95 (s, 2 H), 7.06 (m, 3 H), 7.27 (d, 2 H),7.50 (d, 1 H), 7.63 (s, 1 H), 7.88 (s, 1 H), 8.11(s, 1 H), 13.5 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 458.9.
9
1 HNMR [CDCl3, 400 MHz] δ (ppm): 2.76(m, 1 H), 2.9 (m, 1 H), 3.61 (m, 1 H), 3.76 (m,1 H), 3.93 (m, 1 H), 4.19 (s, 2 H), 6.93 (m, 2 H),7.03 (m, 3 H), 7.23 (m, 3 H), 7.42 (d, 1 H),7.51 (s, 1 H), 7.68 (s, 1 H), 7.78 (s, 1 H), 8.2 (d,1 H); MS (ESI, +ve) m/z M+1 461.1
10
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.8(d, 1 H), 2.91 (d, 1 H), 3.49 (d, 1 H), 3.66 (m,2 H), 3.97 (s, 2 H), 4.72 (s, 2 H), 7.1 (m, 3 H),7.23 (s, 1 H), 7.32 (d, 2 H), 7.61 (d, 1 H), 7.93(s, 1 H), 8.2 (s, 1 H); MS (ESI, +ve) m/z M+1 519.0
11
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.78(m, 1 H), 2.89 (m, 1 H), 3.48 (m, 1 H), 3.66 (m,2 H), 3.95 (s, 2 H), 7.1 (m, 3 H), 7.24 (s, 1 H),7.3 (d, 2 H), 7.53 (d, 1 H), 7.69 (s, 1 H), 8.13(s, 1 H), 13.9 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 458.9.
12
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.77(m, 1 H), 2.88 (m, 1 H), 3.46 (m, 1 H), 3.68 (m,2 H), 3.98 (d, 2 H), 7.1 (m, 3 H), 7.24 (d, 1 H),7.3 (d, 2 H), 7.56 (d, 1 H), 7.88 (s, 1 H), 8.13(s, 1 H), 12.7 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 442.9
13
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.78(m, 1 H), 2.88 (m, 1 H), 3.45 (m, 1 H), 3.67 (m,2 H), 3.95 (s, 2 H), 7.1 (m, 3 H), 7.3 (d, 2 H),7.78 (m, 1 H), 7.88 (s, 1 H), 8.06 (s, 1 H), 8.12(s, 1 H), 12.6 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 477.0
14
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.78(m, 1 H), 2.8 (m, 1 H), 3.46 (m, 1 H), 3.67(m, 2 H), 3.96 (s, 2 H), 6.86 (m, 2 H), 7.12 (m,3 H), 7.23 (m, 1 H), 7.30 (m, 3 H), 7.53 (s,1 H), 7.8 (d, 1 H), 8.1 (s, 1 H), 10.63 (s, 1 H);m/z (relative intensity, %): 461.1 (M + , 100),463 (M + , 33).
15
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.73(m, 1 H), 2.88 (m, 1 H), 3.45 (m, 1 H),3.65 (m, 2 H), 3.95 (s, 2 H), 6.91 (m, 1 H), 7.04(m, 1 H), 7.20 (m, 2 H), 7.27 (m, 3 H), 7.58 (d,1 H), 7.7 (m, 1 H), 7.8 (d, 1 H), 8.0 (m, 1 H),8.14 (s, 1 H); MS (ESI, +ve) m/z M+1 445.1
16
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.77(m, 1 H), 2.8 (m, 1 H), 3.43 (m, 1 H), 3.64(m, 2 H), 3.95 (s, 2 H), 7.05 (d, 2 H), 7.17 (d,1 H), 7.26 (d, 2 H), 7.39 (d, 1 H), 7.63 (s, 1 H),7.69 (d, 1 H), 8.12 (s, 1 H), 13.8 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 443.0
17
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.78(m, 1 H), 2.86 (m, 1 H), 3.4 (m, 1 H), 3.66(m, 2 H), 3.96 (s, 2 H), 6.9 (m, 2 H), 7.0 (m,1 H), 7.11 (m, 3 H), 7.26 (m, 1 H), 7.33 (m,2 H), 7.63 (d, 1 H), 7.85 (m, 1 H), 8.13 (dd,1 H); MS (ESI, −ve) m/z [M−H] − 493.0
18
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.78(m, 1 H), 2.86 (m, 1 H), 3.46 (m, 1 H), 3.65 (m,2 H), 3.96 (s, 2 H), 7.10 (m, 3 H), 7.31 (d, 2 H),7.7 (s, 1 H), 7.76 (d, 1 H), 8.1 (dd, 2 H), 13.5(bs, 1 H); MS (ESI, −ve) m/z [M−H] − 493.0
19
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.83 (m, 1 H), 2.91 (s, 3 H), 3.1 (m, 1 H), 3.5(m, 1 H), 3.62 (m, 2 H), 4.03 (s, 2 H), 7.08 (m,4 H), 7.34 (d, 2 H), 7.61 (d, 2 H), 7.74 (s, 1 H);MS (ESI, +ve) m/z M+1 425.0
20
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.82 (m, 1 H), 2.91 (s, 3 H), 3.1 (m, 1 H), 3.33(m, 1 H), 3.63 (m, 2 H), 4.04 (s, 2 H), 7.08 (m,4 H), 7.34 (d, 2 H), 7.62 (d, 3 H), 13.8 (s, 1 H);MS (ESI, +ve) m/z M+1 441.0
21
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.72(m, 1 H), 2.85 (m, 1 H), 3.46 (m, 1 H), 3.64 (m,2 H), 3.84 (s, 3 H) 3.97 (s, 2 H), 6.91 (d, 2 H),7.03 (d, 1 H), 7.21 (m, 3 H), 7.34 (s, 1 H), 7.6(s, 1 H), 8.1 (s, 1 H), 13.5 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 455.0
22
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.78 (m, 1 H), 2.90 (m, 1 H), 3.45 (m, 1 H),3.47 (m, 2 H), 3.97 (s, 2 H), 4.65 (s, 2 H), 7.12(m, 3 H), 7.32 (d, 2 H), 7.85 (d, 1 H), 7.98 (s,1 H), 8.15 (dd, 2 H);MS (ESI, −ve) m/z [M−H] − 551.0
23
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.75 (m, 1 H), 2.84 (m, 1 H), 3.4 (m, 1 H), 3.64(m, 2 H), 3.95 (s, 2 H), 7.03 (d, 2 H), 7.19 (d,1 H), 7.25 (d, 2 H), 7.40 (d, 1 H), 7.64 (d, 1 H),7.71 (s, 1 H), 8.11 (s, 1 H), 12.5 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 427.0
24
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 2.8(m, 1 H), 2.91 (s, 3 H), 3.13 (m, 1 H), 3.51 (m,1 H), 3.62 (m, 2 H), 4.04 (m, 2 H), 6.93 (m,1 H), 7.03 (dd, 1 H), 7.13 (d, 2 H), 7.35 (m,2 H), 7.54 (m, 1 H), 7.72 (s, 1 H), 12.4 (bs,1 H); MS (ESI, +ve) m/z M+1 443.0
25
1 HNMR [CDCl3, 400 MHz] δ (ppm): 2.77(m, 1 H), 2.89 (m, 1 H), 3.61 (m, 1 H), 3.77 (m,1 H), 3.92 (m, 1 H), 4.19 (s, 2 H) 6.45 (dd, 1 H),6.89 (m, 2 H), 7.03 (m, 4 H), 7.22 (m, 3 H),7.44 (m, 1 H), 7.51 (m, 1 H), 7.68 (m, 1 H),8.48 (m, 1 H); MS (ESI, +ve) m/z M+1 445.1
26
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.78 (m, 1 H), 2.88 (m, 1 H), 3.49 (m, 1 H),3.65 (m, 2 H), 3.98 (s, 2 H), 4.67 (s, 2 H), 7.07(d, 2 H), 7.19 (m, 1 H), 7.29 (m, 3 H), 7.46 (d,1 H), 7.7 (d, 1 H), 7.82 (s, 1 H);MS (ESI, −ve) m/z [M−H] − 501.0
27
1 HNMR [CDCl3, 400 MHz] δ (ppm): 3.0 (m,1 H), 3.06 (s, 3 H), 3.1 (m, 1 H), 3.34 (dd, 1 H),3.68 (dd, 1 H), 3.78 (dd, 1 H), 4.17 (dd, 1 H),4.27 (dd, 1 H), 4.88 (s, 2 H), 6.71 (dd, 1 H),6.86 (dd, 1 H), 7.06 (d, 2 H), 7.27 (d, 1 H), 7.30(d, 1 H), 7.41 (m, 1 H), 7.94 (s, 1 H);MS (ESI, +ve) m/z M+1 517.0
28
1 HNMR [CDCl3, 400 MHz] δ (ppm): 2.97(m, 1 H), 3.1 (m, 4 H), 3.35 (dd, 1 H), 3.67 (dd,1 H), 3.77 (dd, 1 H), 4.25 (q, 2 H), 6.93 (d, 1 H),7.02 (m, 2 H), 7.23 (m, 1 H), 7.30 (m, 2 H), 7.5(m, 2 H); MS (ESI, −ve) m/z [M−H] − 473.3
29
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm):2.84 (m, 1 H), 2.91 (s, 3 H), 3.1 (m, 1 H), 3.53(m, 1 H), 3.63 (m, 2 H), 4.03 (s, 2 H), 7.1 (m,3 H), 7.21 (d, 1 H), 7.35 (d, 2 H), 7.58 (d, 1 H),7.84 (s, 1 H), 12.6 (bs, 1 H);MS (ESI, −ve) m/z [M−H] − 457.2
30
1 HNMR [DMSO-d 6 , 400 MHz] δ (ppm): 3.0(m, 5 H), 3.13 (m, 1 H), 3.7 (m, 2 H), 4.2 (m,2 H), 6.95 (d, 1 H), 7.05 (d, 2 H), 7.2 (m, 3 H),7.41 (d, 1 H), 7.99 (s, 1 H), 9.5 (bs. 1 H);m/z (relative intensity, %): 474.6 (M + , 100),476.7 (M + , 33).
31
1 HNMR [CDCl3, 400 MHz] δ (ppm): 3.0(m, 4 H), 3.33 (m, 2 H), 3.7 (m, 2 H), 4.2 (m,2 H), 7.0 (m, 3 H), 7.23 (m, 2 H), 7.32 (m, 1 H),7.6 (s, 1 H), 7.74 (s, 1 H)MS (ESI, −ve) m/z [M−H] − 456.8
EXAMPLE 32
5-[4-(4-{[5-oxomorpholin-3-yl]methyl}phenoxy)benzyl]-1,3-dihydro-2H-indol 2-one
[0104]
[0105] To the solution of 5-[4-(4-{[5-oxomorpholin-3-yl]methyl}phenoxy)benzylidene]-1,3-dihydro-2H-indol-2-one (0.28 g, 0.657 mmol) in methanol (100 ml) was added 10% Pd/C (0.150 g), and the reaction mixture was hydrogenated at 150 psi for 2-3 hours. On completion of the reaction, as monitored by TLC, the solvent was evaporated under reduced pressure to afford the product as an off white solid (0.034 g). 1 HNMR [CDCl 3 400 MHz] δ (ppm): 2.6 (m, 1H), 2.85 (m, 1H), 3.0 (m, 1H), 3.4 (m, 1H), 3.5 (m, 1H), 3.74 (m, 2H), 3.94 (m, 1H), 4.18 (s, 2H), 5.8 (s, 1H), 6.79 (d, 1H), 6.80 (m, 2H), 6.9 (m, 3H), 7.1 (m, 5H), 7.32 (m, 1H); m/z M+1 429.1
[0106] The following compound was prepared according to the procedure give in the example 32:
[0000]
Example
Structure
Analytical data
33
1 HNMR [DMSO-d 6 , 400 MHz] δ(ppm): 2.71 (m, 1 H), 2.79 (m, 1 H),3.2 (m, 1 H), 3.4 (m, 2 H), 3.62 (m,2 H), 3.94 (m, 2 H), 4.93 (m, 1 H), 6.9(d, 2 H), 7.0 (d, 2 H), 7.2 (d, 2 H),7.29 (d, 1 H), 8.12 (s, 1 H), 12.0 (bs,1 H); MS (ESI, +ve) m/z M+1 431.0
EXAMPLE 34
5-(4-{2-chloro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-yl)methyl]phenoxy}benzyl) morpholin-3-one
[0107]
[0108] To the solution of 5-(4-{2-chloro-4-[(4-oxo-2-thioxo-1,3-thiazolidin-5-ylidene)methyl]phenoxy}benzyl)morpholin-3-one (0.5 g, 1.08 mmol) in toluene (50 ml) was added 1,4-dihydro-3,5-dicarbethoxy-2,6-dimethyl pyridine (0.35 g, 1.41 mmol) and silica gel 60-120 (1.5 g). The reaction mixture was stirred for 24 hr. at 80-85° C. The progress of reaction was monitored by TLC. After completion of reaction solvent was evaporated under reduced pressure to yield crude product which was purified by column chromatography to gave desired product (0.225 g). 1 HNMR [CDCl3, 400 MHz] δ (ppm): 2.6 (m, 1H), 2.87 (m, 1H), 3.2 (m, 1H), 3.5 (m, 1H), 3.61 (m, 1H), 3.8 (m, 1H), 3.93 (m, 1H), 4.19 (s, 2H), 4.57 (m, 1H), 6.1 (s, 1H), 6.9 (m, 3H), 7.08 (d, 1H), 7.16 (d, 2H), 7.34 (s, 1H), 10.0 (bs, 1H); MS (ESI, −ve) m/z [M-H] − 460.9
Protocols for Biological Testing
[0109] Glucose Uptake Assay Using 3T3-L1 cells
[0110] 3T3-L1 cells were differentiated by the addition of differentiation cocktail (72 μg/ml insulin, 0.5 mM IBMX, 400 ng/ml Dexamethasone) for 4 days and were later fed with media without differentation cocktail for 7-8 days. After differentiation the cells were incubated with either the reference compound BLX-1002 or the compounds listed in the table 1 at 1 μM concentrations for 72 hours and the glucose uptake assay was carried out for 10 minutes by the addition of KRP buffer supplemented with 2.5 μCi/ml 14 C deoxy glucose. Stimulation index is defined as the amount of 14 C Deoxyglucose uptake induced by 1 μM of BLX-1002 incubated for 72 hours in an assay condition as per the protocol described above with differentiated 3T3-L1 adipocytes. The values for the compounds mentioned in the table-1 are with reference to the stimulation index of the reference compound BLX-1002.
[0000]
TABLE 1
Effect of compounds on glucose uptake assay in 3T3-L1 cells
Stimulation
Example No
Index
BLX-1002
1.00
1
0.93
2
0.89
3
0.92
4
0.99
5
0.91
6
0.94
7
0.85
8
0.87
10
0.89
11
1.05
12
0.96
13
1.14
14
1.11
17
1.09
19
0.99
20
0.96
34
0.89
DPP IV Assay
[0111] DPP IV assay is carried by using human plasma as a source of DPP IV. The compounds were incubated at a concentration of 1 and 10 μM in an assay buffer containing the DPP IV enzyme for 1 hr, and then the substrate H-gly-pro AMC was added and further incubated for 20 minutes. Subsequently the reaction was stopped on addition of 25% glacial acetic acid. The plates were read in a spectrofluorimeter to get RFU on setting the excitation wavelength of 360 nm and emission wavelength of 460 nm. The percentage inhibition is calculated as compared to the vehicle control. The results are shown in the table-2, all the compounds studied did not produce a significant DPP IV inhibition.
[0000]
TABLE 2
DPP IV inhibition of compounds
% DPP IV
Inhibition
Example No
1 μM
10 μM
9
6.3
7.5
15
12.1
9.1
18
7.3
11.8
19
8.9
15.2
Antidiabetic Activity in Streptozotocin Induced Diabetic Mice
[0112] Female Swiss albino mice, at the age of 10 weeks were used in the study. Diabetes was induced in the animals by injecting streptozotocin by i.p. route at a dose of 200-mg/kg-body weight. 48 hours after streptozotocin administration, the animals were kept fasting for 6 hours. Subsequently blood was collected, plasma separated and the glucose was estimated. Animals showing greater than 200 mg/dl glucose levels were considered as diabetic and these animals were randomly distributed into various groups. The compounds 2 listed in the table 3 were administered at a dose of 50-mg/kg body weight by oral route for 7 days. Later the animals were fasted for 6 hours, the blood was collected and the plasma was separated. Biochemical estimations like glucose, cholesterol and triglycerides were carried out using the plasma. The effect of the compounds mentioned in the table was expressed in terms of percentage reduction in biochemical values as compared to the control group. The results are as shown in the table-3.
[0000]
TABLE 3
Effect of compounds in Streptozotocin induced diabetic mice model
% Reduction
Example No
Glucose
Triglyceride
1
41.6
NR
2
42.6
44.4
7
44.5
60.9 | The present invention relates to novel heterocyclic derivatives of the general formula (I), their pharmaceutically acceptable salts and compositions, their analogs, their tautomeric forms, and their stereoisomers. The present invention more particularly provides novel compounds of the general formula (I). | 2 |
DESCRIPTION
BACKGROUND OF THE INVENTION
Leveling devices in the past have been employed for adjustably supporting loads of varying sizes and weights. The level conditions of machine tools, production equipment, and, more recently, nuclear reactors, have presented a critical need for preciseness. Although several levelers are usually used to obtain this precise condition, full compensation for uneven or non-level supporting planes has been difficult, if possible, to attain. The result of a non-level condition will result in load shifting and an accompanying impairment of operation or other serious and costly consequences.
Previous attempts to compensate for supporting plane unevenness and slope have included the combination of wedges and spherical surfaces, as taught in U.S. Pat. No. 3,306,562, but these earlier devices had a limited range of adjustability and stability. Usually the supporting plane upon which the leveling device was to rest required substantial preparation to approach near levelness.
SUMMARY OF THE INVENTION
An important object of this invention is to provide an improved leveling device designed and constructed so that true level alignment is achieved and maintained while avoiding severe stresses without considerable preparation of the load supporting plane.
Another important object of the invention is to provide an improved leveling device which is self-aligning in any direction for automatically compensating for surface slope.
A further object of the invention is to provide an improved leveling device for carrying heavy loads which is designed in a novel manner to compensate for support plane unevenness or slope without concern for the direction of such unevenness or slope.
Another important object of the invention is to provide an improved leveling device for heavy loads which distributes the load weight over the whole supporting area and minimizes shifting tendencies of the load usually caused by vibration.
To achieve these objectives, the leveling device herein described combines a containing base member, a mechanical means for adjustment of relative position between two wedges and the base, an automatically adjusting third wedge, and a self-aligning load support. While the mechanical shifting of the two wedges accomplishes vertical adjustment, the automatic and self-aligning features of the device are designed to maintain structural strength and stability while compensating for unevenness and lack of level in the support plane.
Other objects and advantages of this invention will be apparent from the following specifications, appended claims, and accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a vertical cross-section of a leveling device embodying the invention;
FIG. 2 is a cross-sectional view taken on the line 2--2 of FIG. 1;
FIG. 3 is a cross-sectional view taken on the line 3--3 of FIG. 1;
FIG. 4 is a horizontal cross-sectional view taken on the line 4--4 of FIG. 1;
FIG. 5 is a horizontal cross-sectional view taken on the line 5--5 of FIG. 1;
FIG. 6 is a schematic view similar to FIG. 1 showing the relative position of its various parts when the device is at its maximum vertical adjustment;
FIG. 7 is similar to FIG. 6 but showing the position of the various parts at the alternative midpoint of vertical adjustment;
FIG. 8 is similar to FIG. 6 but showing the position of the various parts at the lowest vertical adjustment; and
FIG. 9 is a schematic view similar to FIG. 6 showing the position of the various parts at the preferred midpoint of vertical adjustment.
DESCRIPTION OF PREFERRED EMBODIMENT
With particular reference to FIGS. 1 to 3, the preferred embodiment of the invention disclosed therein comprises a base member 10 of general U-shape formation, including a bottom portion 12 and two opposite end wall portions 14 and 16; end wall 14 being an integral part of base 10 and end wall 16 being a separate piece bolted to base 10 by bolts 13, only one of which is shown. The cradle-like appearance of base member 10 forms a partial housing for a pair of superimposed wedge-shaped members, the upper one being indicated at 20, the lower one being indicated at 18. The lower wedge 18 is seated in the cradle of base 10 on the upwardly facing inclined surface 15. The lower wedge has a downwardly facing inclined surface 17 which slidably engages the surface 15. The lower wedge has a generally horizontally extending upwardly facing surface 19 which slidably engages the complementary horizontal surface 23 of the upper wedge. Both wedges are permitted relative longitudinal sliding movement in the direction of one or the other of the end walls 14 and 16. The two wedges are of equal size and of a length less than the distance between the confronting surfaces of the end walls, and both serve to function as sliding and lifting wedges.
A third wedge, load supporting member 22, is a portion of the load engaging means and rests upon the upper wedge 20. This third wedge has an inclined downwardly facing surface 25 which is slidably supported on a complementary upwardly facing inclined surface 27 of the upper wedge 20. The third wedge 22 functions as a lifting wedge. The three wedges are designed to nest within the end walls of the base 10.
Torque means is provided for slidably adjusting the wedges. Such means comprises an adjusting screw 24 operatively engaging the lower and upper wedges 18 and 20, and having polygonally shaped head 26 which is engageable by a tool for turning purposes. To prevent sidewise movement, each wedge has downwardly extending tongues 18a, 20a, and 22a which overlap the member below as shown in FIGS. 2 and 3. For this purpose, wedges 18 and 20 are provided with grooves 18b and 20b into which the complementary tongues are received.
The wedges 18, 20 and 22 have relatively wide dimensions, as shown in the FIGS. 2 and 3, and the engagement of their respective interfaces, as well as the engagement of the interface of wedge 18 and base 10, is maintained against lateral movement as above described. The action of raising and lowering a load to a desired level line is achieved by converting horizontal motion into vertical motion and particularly by the interaction of the inclined planes of wedge members 18, 20 and 22. More specifically, the shank of screw 24 is slidably received in an upwardly opening slot 11 of frame wall 14. Torque applied to screw head 26 causes rotation of screw 24 within the operatively engaged portions of wedges 18 and 20. This rotation is converted into longitudinal forces acting upon the wedges and a resultant relative longitudinal shift occurs. The load supporting member 22 adjusts itself on the upwardly inclined surface 27 of upper wedge 20 so as to maintain contact with the end wall 14, thus, as the lower and upper wedges are moved longitudinally relative to each other by the rotation of the adjusting screw in either direction, the load supporting member is moved vertically by the interaction of the inclined wedging surfaces.
Relative longitudinal movement of the upper and lower wedges is accomplished by an idler coupling 30 connected to the lower wedge 18 and an adjusting nut 32 connected to the upper wedge 20. The idler coupling comprises a pair of U-shaped internally radially grooved members 30a and 30b encircling and meshing with a similarly radially grooved portion of screw 24, said U-shaped members joined to each other and attached to lower wedge 18 by bolts 34, FIG. 2. Although the meshed radial grooves of said screw and U-shaped members are designed without pitch to allow rotation of said screw in said coupling and not cause longitudinal movement of these members relative to each other, a longitudinal movement of said screw or wedge will force concurrent longitudinal movement in the coupled members.
The adjusting nut 32 is attached to upper wedge 20 by bolts 33, FIG. 3. The nut has a thread pitch which, when the nut is threadedly engaged with a similarly pitched portion of screw 24 and the screw is rotated, will cause a longitudinal movement of nut and screw relative to each other. The idler coupling 30 is attached to a longitudinally extending channel 36 in lower wedge 18, FIG. 2, and, similarly, the adjusting nut 32 is attached to a longitudinally extending channel 38 in upper wedge 20, FIG. 3. FIGS. 2 through 5 illustrate that channels 36 and 38 provide clearance for fore and aft movement of idler 30 and nut 32. Thus, with the connection of screw 24 to nut 32 and idler 30 as described, rotation of said screw will cause longitudinal relative movement between wedges 18 and 20.
Reference to FIGS. 6 through 9 will illustrate the novel combination which converts rotational movement of the adjusting screw 24 into longitudinal movement of the lower and upper wedges 18 and 20 with the ultimate vertical movement of the load supporting member 22. FIG. 6 depicts the leveling device at its maximum vertical extension with upper wedge 20 in contact with base end wall 14 and lower wedge 18 in contact with the opposite base end wall 16. Rotation of adjusting screw 24 will cause nut 32 and its attached upper wedge 20 to move away from base end wall 14. The force of the load support member 22 on inclined interface of surfaces 25 and 27 will cause the load support member 22 to continuously adjust itself to maintain contact with end wall 14 as wedge 20 moves toward end wall 16. Idler coupling 30 allows the rotation of screw 24 without disturbance of wedge 18. As wedge 20 moves to contact wall 16, the retreat of its wedge shape from beneath support member 22 allows member 22 to lower until the device reaches the status depicted by FIG. 7. At this point, wedge 20 is restrained by wall 16. Since continued rotation of screw 24 forces continued relative longitudinal movement between adjusting nut 32 and said screw, and since said nut is attached to wedge 20 and wedge 20 is now constrained by end wall 16, further rotation of said screw will cause the screw to retreat from the now stationary nut and attached wedge 20. The retreat of screw 24 is evident by the retreat of screw head 26 from end wall 14, FIG. 8. As said screw retreats, it draws the idler 30 and its attached lower wedge 18 towards wall 14. The effect of the retreat of wedge 18 down the interface of surfaces 15 and 17 is to cause a lowering of upper wedge 20 and the resultant decrease in height of the load support member 22 until the status of FIG. 8 is attained. This is the lowest vertical height of the device. Because surfaces 15 and 27 are parallel, it is obvious that a reverse direction of rotation of screw 24 will cause the wedges to retreat from wall 16 by the principles discussed above and effect the status depicted by FIG. 9.
The invention provides compensation for an unevenness or slant of the supporting surface or floor upon which the leveling device is set. This is achieved by "floatingly" supporting the load for universal movement in any direction. For accomplishing this purpose, the device is provided with an alignment compensating means having mated relatively shiftable spherical surfaces. More specifically, and with particular reference to FIGS. 1 and 2, the aligning means comprises a load engaging member 28 having a downwardly directed convex spherical surface 44 and the top side of the load supporting member 22 is provided with a mating concave spherical recess 46 of the same radius of curvature as the surface 44.
In plan view the load engaging or alignment compensating member 28, is of circular outline. It is provided with a central upwardly projecting boss 48 for engagement with the supporting structure of the load which the leveler will support. When laid on a floor, the load leveling base member 10 will assume whatever inclination the floor has. The alignment compensating member 28 is free to slide over the spherical surface 46 of the load supporting member 22 in any direction as the heavy load carried thereby is vertically adjusted and leveled. Any slant in the floor within the capability of the leveling assembly can be readily compensated for in this manner.
A leveling device constructed in accordance with this invention, in carrying out its function of supporting heavy loads, will spread or distribute the forces of the load equally over the wide surface of the spherical portions 44 and 46, and thereby avoid load concentrations at any low spot or line which might easily cause a fracture of one of the parts of the leveler. No care need be exercised about the direction of floor slant and the disposition of the parts of the leveler with respect thereto. During the operation of vertically adjusting and leveling the load, the base 10 and the wedging members contained therein may be slid and swiveled under the spherical protuberance 44 of the alignment compensating means regardless of the floor slant. Final adjustments of previous levelers could cause the entire leveling device to move to the extreme limits of its self-aligning capability and thus move the load stress to the outer limits of the device. The embodiment of the present invention provides the alignment capabilities of the spherical surfaces 44 and 46 while presenting the novel design feature that allows the load supporting member 22 to maintain its position against end wall 14, thus maintaining the load forces at the center of mass and structural strength of the assembled device. Although the embodiment herein presented places the alignment compensating means on top of the leveling device, it would be obvious to one skilled in the art that such alignment means might also be placed under the base 10 without adverse effect on the other basic features of the device.
In the described embodiment of this invention, horizontal surfaces 12 and 19 are parallel and the angles of the inclined surfaces are equal, making surface 15 parallel to surface 27. This relationship between said surfaces is not necessary for successful employment of the device and other combinations of surface relationships may be employed. However, it has been found that variations of slope in the surfaces will affect the torque requirements necessary for adjustment as well as vary the range of vertical adjustment available to the user. The preferred embodiment of said surface relationships provides a "locking angle" which gives stability to the final adjustment of the device.
While the preferred embodiment of the invention has been described and illustrated, it is to be understood that it is capable of variation and modification without departing from the spirit and scope of the invention. | A leveling device for mounting and leveling heavy loads independent of the inclination of the floor upon which the device is supported utilizes a plurality of wedges disposed between a base member and a load supporting member in combination with mated spherical surfaces to provide two self-adjusting features which obviate concern for non-level mounting surfaces or misaligned loads. | 5 |
FIELD OF THE INVENTION AND RELATED ART
[0001] The present invention relates to a process cartridge, and an image forming apparatus which employs a process cartridge.
[0002] Here, an “electrophotographic image forming apparatus” means an apparatus, such as an electrophotographic copying machine, an electrophotographic printer (laser beam printer, LED printer, etc.), or the like, which forms an image on recording medium, with the use of an electrophotographic image forming method.
[0003] A “process cartridge” means a cartridge in which an electrophotographic photosensitive drum, and one or more process means, that is, a charging means, and a developing means or a cleaning means, for processing the electrophotographic photosensitive drum, are integrally disposed so that they can be removably mountable in the main assembly of the image forming apparatus. More specifically, a process cartridge is a cartridge in which an electrophotographic photosensitive drum, and at least one among the abovementioned processing means, such as a developing means, a charging means, and a cleaning means, are integrally disposed. It also means a cartridge in which at least a developing means as a processing means, and an electrophotographic photosensitive drum, are integrally disposed so that they can be removably mountable in the main assembly of an electrophotographic image forming apparatus.
[0004] In the field of an electrophotographic image forming apparatus which employs one of the electrophotographic image formation processes, a process cartridge system has long been employed, according to which an electrophotographic photosensitive drum, and a single or plurality of processing means which act on the electrophotographic photosensitive drum, are integrally disposed in a cartridge to make it possible for them to be removably mountable in the main assembly of the image forming apparatus. Also according to this process cartridge system, an image forming apparatus can be maintained by a user himself, without relying on a service person, drastically improving the image forming apparatus in operability. Thus, a process cartridge system is widely in use in the field of image forming apparatus.
[0005] The image forming operation of an electrophotographic image forming apparatus is as follows: First, the electrophotographic photosensitive drum is exposed to a beam of light projected from a laser, an LED, an ordinary electric light, or the like, while being modulated with pictorial information, forming thereby an electrostatic latent image on the photosensitive drum. The electrostatic latent image is developed by the developing apparatus. Then, the developed image on the photosensitive drum is transferred onto recording medium; an image is formed on the recording medium.
[0006] As regards the structure for positioning the process cartridge in the main assembly of the image forming apparatus, the following structure is known. A supporting member for supporting the process cartridge is pushed into the main assembly of the apparatus. Then, the process cartridge is raised by the engagement between the cartridge side positioning portion and the main assembly side positioning portion. Thereafter, the process cartridge is separated from the supporting member. In this manner, the process cartridge is positioned to the main assembly without interference from the supporting member. (Japanese Laid-open Patent Application Hei 6-29998). It is desirable that the mounting and the mounting operation of the process cartridge relative to the main assembly of the apparatus is simple and easy.
[0007] The present invention is one of the further developments of the above described prior art.
SUMMARY OF THE INVENTION
[0008] Thus, the primary object of the present invention is to provide a process cartridge and an electrophotographic image forming apparatus in which when the process cartridge is mounted to the main assembly of the apparatus, a first cartridge side portion to be positioned and a second cartridge side portion to be positioned are less frictioned relative to a member or members of the main assembly.
[0009] It is another object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus in which when the process cartridge is mounted to the main assembly of the apparatus, a first cartridge side portion to be positioned and a second cartridge side portion to be positioned are less contacted to a member or members of the main assembly.
[0010] It is a further object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus in which the mounting operativity of the process cartridge relative to the main assembly of the apparatus is improved.
[0011] It is a further object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus in which the process cartridge can be mounted to the main assembly of the apparatus with the stability.
[0012] It is a further object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus in which the positioning accuracy of the process cartridge in the main assembly is improved.
[0013] It is a further object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus in which the positioning accuracy of the process cartridge in the main assembly is stably high.
[0014] According to an aspect of the present invention, there is provided a process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, wherein said apparatus includes a first main assembly side positioning portion, a second main assembly side positioning portion, a first main assembly side guide, a second main assembly side guide, a first main assembly side regulating portion, a second main assembly side regulating portion, an urging member for urging process cartridge to the main assembly side positioning portion by an urging force, said process cartridge comprising an electrophotographic photosensitive drum; process means actable on said electrophotographic photosensitive drum; a first cartridge side portion-to-be-guided to be guided by the first main assembly side guide when said process cartridge enters the main assembly along an axial direction of said electrophotographic photosensitive drum; a second cartridge side portion-to-be-guided to be guided by the second main assembly side guide when said process cartridge advances in the main assembly along the axial direction of the electrophotographic photosensitive drum in mounting it to the main assembly; a first cartridge side portion-to-be-regulated, provided at a leading side with respect to the advancing direction, for being regulated by the first main assembly side regulating portion in upward movement thereof when said process cartridge advancing in the main assembly while being guided by the first main assembly side guide and the second main assembly side guide is urged upwardly by the urging force of said urging member; a second cartridge side portion-to-be-regulated, provided at a trailing side with respect to the advancing direction, for being regulated by the first main assembly side regulating portion in upward movement thereof when said process cartridge advancing in the main assembly while being guided by the first main assembly side guide and the second main assembly side guide is urged upwardly by the urging force of said urging member; a first cartridge side portion to be positioned to be positioned at the first main assembly side positioning portion by the urging force of said urging member after said first cartridge side portion-to-be-regulated advancing in the main assembly while being regulated in the upward movement by said first main assembly side regulating portion passes the first main assembly side regulating portion; and a second cartridge side portion to be positioned to be positioned at the second main assembly side positioning portion by the urging force of said urging member after said second cartridge side portion-to-be-regulated advancing in the main assembly while being regulated in the upward movement by said second main assembly side regulating portion passes the second main assembly side regulating portion, wherein said process cartridge is mounted to the main assembly with said first cartridge side portion to be positioned at the first main assembly side positioning portion by the urging force of said urging member and with said second cartridge side portion to be positioned at the second main assembly side positioning portion by the urging force of said urging member.
[0015] According to the present invention, a process cartridge and an electrophotographic image forming apparatus in which when the process cartridge is mounted to the main assembly of the apparatus, a first cartridge side portion to be positioned and a second cartridge side portion to be positioned are less frictioned relative to a member or members of the main assembly, can be provided.
[0016] According to the present invention, a process cartridge and an electrophotographic image forming apparatus in which when the process cartridge is mounted to the main assembly of the apparatus, a first cartridge side portion to be positioned and a second cartridge side portion to be positioned are less contacted to a member or members of the main assembly, can be provided.
[0017] According to the present invention, a process cartridge and an electrophotographic image forming apparatus in which the mounting operativity of the process cartridge relative to the main assembly of the apparatus is improved, can be provided.
[0018] According to the present invention, a process cartridge and an electrophotographic image forming apparatus in which the process cartridge can be mounted to the main assembly of the apparatus with the stability, can be provided.
[0019] According to the present invention, a process cartridge and an electrophotographic image forming apparatus in which the positioning accuracy of the process cartridge in the main assembly is improved, can be provided.
[0020] According to the present invention, a process cartridge and an electrophotographic image forming apparatus in which the positioning accuracy of the process cartridge in the main assembly is stably high, can be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a schematic sectional view of the electrophotographic color image forming apparatus in the first of the preferred embodiments of the present invention, showing the general structure of the apparatus.
[0022] FIG. 2 is a cross-sectional view of the cartridge, showing the general structure of the cartridge.
[0023] FIG. 3 is a perspective view of the cartridge and image forming apparatus when the former is in the position from which it is mounted into the latter.
[0024] FIG. 4 is an external perspective view of the process cartridge.
[0025] FIG. 5 is a schematic drawing of the cartridge positioning portion of the main assembly of the image forming apparatus, and the cartridge pressing portion of the main assembly of the image forming, showing their structures.
[0026] FIG. 6 is a detailed view of the cartridge positioning mechanism and cartridge pressing mechanism, on the rear side, of the main assembly of the image forming apparatus, showing their structures.
[0027] FIG. 7 is a detailed view of the cartridge positioning mechanism and cartridge pressing mechanism, on the front side, of the main assembly of the image forming apparatus, showing their structures.
[0028] FIG. 8 is a plan view of the cartridge pressing rear mechanism of the main assembly of the image forming apparatus, as seen from the right-hand side (as seen from front side of main assembly), showing the operation of the cartridge pressing mechanism.
[0029] FIG. 9 is a plan view of the cartridge pressing rear mechanism of the main assembly of the image forming apparatus, as seen from the leading end side of the cartridge in terms of the direction in which the cartridge is mounted, showing the operation of the cartridge pressing mechanism.
[0030] FIG. 10 is a plan view of the cartridge pressing front mechanism of the main assembly of the image forming apparatus, as seen from the left-hand side (as seen from front side of main assembly), showing the operation of the cartridge pressing mechanism.
[0031] FIG. 11 is a plan view of the cartridge pressing front mechanism of the main assembly of the image forming apparatus, as seen from the trailing end side of the cartridge in terms of the direction in which the cartridge is mounted, showing the operation of the cartridge pressing mechanism.
[0032] FIG. 12 is a schematic drawing which shows the directions in which force is applied during the mounting or removal of the cartridge.
[0033] FIG. 13 is an external perspective view of the cartridge in the second embodiment of the present invention.
[0034] FIG. 14 is a schematic drawing which depicts the cartridge positioning mechanism and cartridge pressing mechanism of the main assembly of the image forming apparatus in the second embodiment of the present invention.
[0035] FIG. 15 is a sectional view of the cartridge, at a horizontal plane which coincides with the axial line of the photosensitive drum, as seen from above.
[0036] FIG. 16 is a plan view of the cartridge pressing rear mechanism of the main assembly of the image forming apparatus in the second embodiment, as seen from the right-hand side (as seen from front side of main assembly), showing the operation of the cartridge pressing mechanism.
[0037] FIG. 17 is a plan view of the cartridge pressing rear mechanism of the main assembly of the image forming apparatus in the second embodiment, as seen from the leading end side of the cartridge in terms of the direction in which the cartridge is mounted, showing the operation of the cartridge pressing mechanism.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiment 1
[0038] Hereafter, the process cartridge (which hereafter will be referred to as “cartridge” and electrophotographic color image forming apparatus (which hereafter will be referred to as “image forming apparatus”) in the first of the preferred embodiments of the present invention will be described with reference to the appended drawings.
(General Structure of Image Forming Apparatus)
[0039] First, referring to FIG. 1 , the image forming apparatus in this embodiment will be described regarding its general structure. An image forming apparatus 100 shown in FIG. 1 has four cartridge bays 22 ( 22 a - 22 d ), that is, the spaces into which four cartridges are mountable one for one ( FIG. 3 ). The four cartridge bays 22 are juxtaposed side by side (in parallel), in a single straight row angled relative to the horizontal direction. The cartridge 7 in each cartridge bay 22 ( 22 a - 22 d ) has one electrophotographic photosensitive drum 1 ( 1 a - 1 d ).
[0040] The electrophotographic photosensitive drum 1 (which hereafter may be referred to as “photosensitive drum”) is rotationally driven in the clockwise direction of the drawing, by a driving member (unshown). Each cartridge 7 also has the following processing means, which are disposed in the adjacencies of the peripheral surface of the photosensitive drum 1 in a manner to surround the photosensitive drum 1 , in the order in which they will be listed next. They are a cleaning means 6 ( 6 a - 6 d ), which removes the developer (which hereafter may be referred to as “toner”) remaining on the peripheral surface of the photosensitive drum 1 after the transfer, a charge roller 2 ( 2 a - 2 d ) which uniformly charges the peripheral surface of the photosensitive drum 1 , a scanner unit 3 which forms an electrostatic latent image on the peripheral surface of the photosensitive drum 1 , by emitting a beam of laser light while modulating the beam of laser light with pictorial information, a development unit 4 ( 4 a - 4 d ) which develops the electrostatic latent image on the peripheral surface of the photosensitive drum 1 with the use of toner, and an intermediary transfer belt 5 onto which the four toner images on the photosensitive drums, one for one, which are different in color, are sequentially transferred. The photosensitive drum 1 , cleaning member 6 , charge roller 2 , and development unit 4 are integrated in the form of a cartridge (process cartridge), that is, the cartridge 7 , which is removably mountable in the main assembly 100 a of the image forming apparatus 100 by a user.
[0041] The intermediary transfer belt 5 is stretched around a driver roller 10 and a tension roller 11 , being thereby supported by them. The main assembly 100 a of the image forming apparatus 100 is provided with first transfer rollers 12 ( 12 a - 12 d ), which are on the inward side of the loop which the intermediary transfer belt 5 forms. The first transfer rollers 12 are positioned so that they oppose the photosensitive drums 1 ( 1 a - 1 d ), one for one. To the transfer belt 5 , transfer bias is applied from a bias applying means (unshown).
[0042] After the formation of a toner image on the photosensitive drum 1 , the toner image is transferred onto the intermediary transfer belt 5 . More specifically, four toner images are formed on the four photosensitive drums 1 , one for one. Then, as the four photosensitive drums 1 are further rotated in the direction indicated by an arrow mark Q, and the intermediary transfer belt 5 is rotated in the direction indicated by an arrow mark R, the four toner images are sequentially transferred (first transfer) in layers onto the intermediary transfer belt 5 , by the positive bias applied to the first transfer rollers 12 . Then, the four layers of toner images on the intermediary transfer belt 5 , which are different in color, are conveyed to a second transferring portion 15 .
[0043] Meanwhile, in synchronism with the progression of the abovementioned image forming operation, a sheet S of recording medium is conveyed by a sheet conveying means made up of a sheet feeding-and-conveying apparatus 13 , a pair of registration rollers 17 , etc. The sheet feeding-and-conveying apparatus 13 has a sheet feeder cassette 24 in which multiple sheets S are storable, a sheet feeder roller 8 which conveys the sheet S, and a pair of sheet conveying rollers 16 which conveys further the sheet S after the feeding of the sheet S into the main assembly 100 a of the image forming apparatus 100 . The main assembly 100 a is structured so that the sheet feeder cassette 24 can be pulled out of the main assembly 100 a in the frontward direction of the main assembly 100 a , in FIG. 1 . The sheets S in the sheet feeder cassette 24 are kept pressed by the sheet feeder roller 8 , and fed into the main assembly 100 a by the sheet feeder roller 8 , while being separated one by one by a sheet separator pad 9 (friction-based sheet separating method).
[0044] After being fed into the main assembly 100 a from the sheet feeding apparatus 13 , the sheet S is conveyed to the second transfer portion 15 by the pair of registration rollers 17 . In the second transfer portion 15 , positive bias is applied to the second transfer roller 18 , whereby the four toner image on the intermediary transfer belt 5 , which are different in color, are transferred (second transfer) onto the sheet S as the sheet S is conveyed through the second transfer portion 15 .
[0045] A fixing portion 14 as a fixing means is a portion of the image forming apparatus, which fixes the toner images on the sheet S by applying heat and pressure. A fixation belt 14 a is cylindrical, and is guided by a belt guiding member (unshown) having a heat generating means, such as a heater, bonded to the belt guiding member. The fixation belt 14 a and a pressure application roller 14 b are kept pressed against with each other by the application of a preset amount of pressure thereto, forming thereby the fixation nip.
[0046] After the transfer of the toner images (unfixed toner images) onto the sheet S from the image forming portion, the sheet S is conveyed to the fixing portion 14 , and then, is conveyed through the fixation nip between the fixation belt 14 a and pressure application roller 14 b in the fixing portion 14 . As the sheet S is conveyed through the fixation nip, the sheet S and the toner images thereon are subjected to heat and pressure. As a result, the unfixed toner images on the sheet S become fixed to the sheet S. Thereafter, the sheet S having the fixed toner images is discharged into a delivery tray 20 by a pair of sheet discharging rollers 19 .
[0047] Meanwhile, the toner remaining on the peripheral surface of the photosensitive drum 1 after the toner image transfer is removed by the cleaning member 6 . Then, the removed toner is recovered into a chamber for the recovered toner, which is in the photosensitive member unit 26 ( 26 a - 26 d ).
[0048] As for the toner remaining on the intermediary transfer belt 5 after the transfer (second transfer) of the toner images onto the sheet S, it is removed by a transfer belt cleaning apparatus 23 . The removed toner is recovered into a waste toner container (unshown) located in the rear portion of the image forming apparatus, through the waste toner passage (unshown).
(Cartridge)
[0049] Next, referring to FIG. 2 , the cartridge in this embodiment will be described. FIG. 2 is a cross-sectional view of the cartridge 7 , in which a substantial amount of toner t is present. Incidentally, a cartridge 7 a , that is, a cartridge in which the toner t of yellow color is present, a cartridge 7 b , that is, a cartridge in which the toner t of magenta color is present, a cartridge 7 c , that is, a cartridge in which the toner t of cyan color is present, and a cartridge 7 d , that is, a cartridge in which the toner t of black color is present, are the same in structure.
[0050] Each cartridge 7 is made up of a photosensitive member unit 26 and a development unit 4 . The photosensitive member unit 26 is provided with the photosensitive drum 1 , charge roller 2 (charging means), and cleaning member 6 (cleaning means). The development unit 4 has a development roller 25 .
[0051] The photosensitive drum 1 is rotatably supported by the cleaning means frame 27 of the photosensitive member unit 26 , with the interposition of a pair of bearings which will be described later. In an image forming operation, the photosensitive drum 1 is rotationally driven, by transmitting to the photosensitive member unit 26 the driving force from a motor (unshown). There are the charge roller 2 and cleaning member 6 in the adjacencies of the peripheral surface of the photosensitive drum 1 as described above. As the above described transfer residual toner is removed from the peripheral surface of the photosensitive drum 1 by the cleaning member 6 , the removed toner falls into a chamber 27 a for the removed toner. The cleaning means frame 27 is also provided with a pair of charge roller bearings 28 , which are attached to the cleaning means frame 27 in such a manner that the charge roller bearings 28 are movable in the direction indicated by a double-headed arrow mark D, which connects the centers of the charge roller 2 and photosensitive drum 1 . The shaft 2 j of the charge roller 2 is rotatably supported by the charge roller bearings 28 , and the bearings 28 are kept pressured toward the photosensitive drum 1 by a pair of charge roller pressing members 46 .
[0052] The development unit 4 has the development roller 25 and a developing means frame 31 . The development roller 25 rotates in contact with the photosensitive drum 1 in the direction indicated by the arrow mark B. The development roller 25 is rotatably supported by a developing means frame 31 . More specifically, the development roller 25 is supported by a pair of bearing members 32 ( 32 R and 32 L) attached to the lengthwise ends of the developing means frame 31 . The development unit 4 is provided with a toner supply roller 34 and a development blade 35 . The toner supply roller 34 rotates in contact with the development roller 25 in the direction indicated by an arrow mark C. The development blade 35 is for regulating in thickness the toner layer on the peripheral surface of the development roller 25 . Further, the development unit 4 has a toner conveying member 36 for conveying the toner in the toner storage portion 31 a of the development unit 4 to the toner supply roller 34 while stirring the toner. The toner conveying member 36 is in the toner storage portion 31 a.
[0053] The development unit 4 is connected to the photosensitive member unit 26 . More specifically, a pair of pins 37 ( 37 R and 37 L) are put through, one for one, the holes 32 Rb and 32 Lb of the bearing members 32 R and 32 L, respectively, so that the development unit 4 is pivotally movable relative to the photosensitive member unit 26 about the pins 37 ( 37 R and 37 L). The development unit 4 is under the pressure from pressure application springs 38 . Therefore, when the cartridge 7 is used for image formation in the main assembly of the image forming apparatus, the development unit 4 rotates about the pins 37 in the direction indicated by an arrow mark A, placing thereby the development roller 25 in contact with the photosensitive drum 1 .
[0000] (Structure of Means for Mounting Cartridge into Main Assembly of Image Forming Apparatus)
[0054] Next, referring to FIG. 3 , the portion of the cartridge, which allows the cartridge to be removably mounted into the main assembly of the image forming apparatus, and the portion of the main assembly of the image forming apparatus, which allows the cartridge to be removably mounted into the main assembly of the image forming apparatus, will be described regarding their structures.
[0055] FIG. 3 is a perspective view of the cartridge and image forming apparatus when the former is in the position from which it is mounted into the latter. Incidentally, in this embodiment, the cartridge and the main assembly 100 a of the image forming apparatus 100 are structured so that the former is inserted into the latter, in the front-to-rear direction, that is, the direction indicated by an arrow mark F, which is parallel to the axial line of the photosensitive drum 1 , so that the cartridge 7 can be removably mounted into the main assembly 100 a.
[0056] Referring to FIG. 3 , the main assembly 100 a is provided with a cover 21 (front cover), which is on the front side of the main assembly 100 a . The front cover 21 can be opened or closed. Opening the front cover 21 exposes the four cartridge bays 22 ( 22 a - 22 d ), which are for the cartridges 7 ( 7 a - 7 d ), one for one. The four cartridge bays 22 are juxtaposed side by side (in parallel), in a singe straight row angled relative to the horizontal direction. The main assembly 100 a is provided with top cartridge guides 80 ( 80 a - 80 d ) as first cartridge guides of the main assembly 100 a , and bottom cartridge guides 81 ( 81 a - 80 d ) as second cartridge guides of the main assembly 100 a . The top and bottom cartridge guides 80 and 81 are located at the top and bottom of the four cartridge bays 22 , one for one, and extend from the front to rear of the main assembly 100 a . The photosensitive member unit 26 of each cartridge 7 is provided with a projection 29 (first portion by which cartridge is guided), and a tongue-like portion 30 (second portion by which cartridge guided) by which the cartridge 7 is guided when the cartridge 7 is mounted into, or removed from, the corresponding cartridge bay 22 . More specifically, in order to mount the cartridge 7 into the corresponding cartridge bay 22 , the projection 29 and tongue-like portion 30 of the photosensitive member unit 26 are to be fitted in the cartridge guides 80 and 81 of the main assembly 100 a , respectively, and then, the cartridge 7 is to be pushed into the cartridge bay in the direction indicated by an arrow mark F in the drawing.
[0057] Incidentally, the abovementioned projection 29 (first portion of cartridge 7 , by which cartridge 7 is guided) is located at the top of the leading end of the cartridge 7 , in terms of the direction in which the cartridge 7 is inserted into the main assembly 100 a , whereas the tongue-like portion 30 (second portion of cartridge 7 , by which cartridge 7 is guided) is on the bottom surface of the cartridge 7 , and extends from the leading end to the trailing end.
[0058] Each cartridge 7 is also provided with a pair of cartridge positioning portions 40 a and 50 a (by which cartridge 7 is positioned relative to main assembly 100 a ), which are located at the leading and trailing ends of the cartridge 7 , in terms of the abovementioned cartridge insertion direction. The operation to mount the cartridge 7 into the main assembly 100 a concludes as the cartridge 7 becomes correctly positioned in the main assembly 100 a . Incidentally, for the purpose of controlling the rotation of the cartridge 7 , which occurs as driving force is transmitted to the cartridge 7 , the leading end of the cartridge 7 is provided with a shaft 27 b ( FIG. 4 ), which protrudes in the direction parallel to the cartridge mounting direction (cartridge insertion direction), whereas the trailing end of the cartridge 7 is provided with a groove 27 c , which is U-shaped in cross section. As the cartridge 7 becomes correctly positioned in the main assembly 100 a , the shaft 27 b fits into a hole 82 b ( FIG. 5 ) of the main assembly 100 a , which is elongated in cross section, and the shaft 92 c ( FIG. 5 ) of the main assembly 100 a fits into the groove 27 c of the cartridge 7 .
[0059] In terms of the direction in which the cartridge 7 advances as it is inserted into the main assembly 100 a , the projection 29 (by which cartridge 7 is guided) of the cartridge 7 is located at the top of the leading end of the cartridge 7 , as described above. The tongue-like portion 30 of the cartridge 7 is on the bottom surface of the cartridge 7 , extending from the leading end of the cartridge 7 to the trailing end of the cartridge 7 . Further, in terms of the direction perpendicular to the axial line of the photosensitive drum 1 , the tongue-like portions 29 and 30 are on the same side of the photosensitive drum 1 .
[0060] Therefore, it is ensured that the cartridge 7 reliably advances into the main assembly 100 a.
[0061] As for the structural arrangement for correctly positioning the cartridge 7 in the main assembly 100 a , it will be described later in detail.
(Structure for Correctly Positioning Cartridge, and Structure for Pressing Cartridge)
[0062] Next, referring to FIGS. 4-7 , the structural arrangement, in this embodiment, for correctly positioning the cartridge relative to the main assembly 100 a , and the structural arrangement for pressing the cartridge to correctly positioning the cartridge, will be described.
[0063] FIG. 4 is an external perspective view of the cartridge in this embodiment. The photosensitive drum 1 , which the cartridge 7 has, is rotatably supported, by the lengthwise end portions of its shaft (unshown), by a pair of bearings 40 and 50 , one for one, which are solidly attached to the cleaning means frame 27 .
[0064] The bearing 40 (first bearing which supports one of lengthwise ends of shaft of photosensitive drum 1 ) is the bearing on the rear side, that is, the leading end side in terms the direction in which the cartridge 7 is made to advance in the main assembly 100 a when it is mounted into the main assembly 100 a . It is provided with a cartridge positioning first portions 40 a ( 40 a 1 , 40 a 2 ), which are two portions of the top side of the peripheral surface of the bearing 40 a . More specifically, the cartridge positioning first portion 40 a (which is made up of portions 40 a 1 and 40 a 2 ) is for correctly positioning the leading end of the cartridge 7 relative to the main assembly 100 a , in terms of the direction vertical to the abovementioned cartridge advancement direction. It is arcuate in cross section. Incidentally, in terms of the cartridge advancement direction, the bearing 40 , that is, the bearing which will be at the deepest end of the cartridge bay, is located at the downstream end of the cartridge 7 ( FIG. 4 ). The cartridge 7 is also provided with a pressure catching portion 40 b , which catches the pressure applied to the cartridge 7 by the cartridge pressing member 83 (which may be referred to as pressure applying member, or upwardly pushing member), which is a portion of the bottom side of the peripheral surface of the cartridge positioning first portion 40 a . Incidentally, the above-mentioned cartridge advancement direction is the direction in which the cartridge 7 is advanced into the main assembly 100 a when a user mounts the cartridge 7 into the main assembly 100 a.
[0065] Further, the abovementioned cartridge positioning portions 40 a ( 40 a 1 and 40 a 2 ) is positioned so that it straddles the axial line I of the photosensitive drum 1 ( FIG. 15 ). That is, the cartridge 7 has the cartridge positioning first portion 40 a 1 , which is on one side of the axial line I of the photosensitive drum 1 , and the cartridge positioning second portion 40 a 2 , which is on the other side of the axial line I of the photosensitive drum 1 . The cartridge positioning first portion 40 a 1 (positioning portion on leading end side) is on the opposite side of the abovementioned axial line I from the cartridge positioning second portion 40 a 2 (positioning portion on trailing end side) ( FIG. 15 ). As for the abovementioned pressure catching portion 40 b , it is on the downstream side of the photosensitive drum 1 in terms of the cartridge advancement direction. As seen from the direction J ( FIG. 9( c )) in which upward pressure is applied by the abovementioned pressing member 83 (pressure applying member, upwardly pushing member), the pressure catching portion 40 b is (roughly at the mid point) between the cartridge positioning first and second portions 40 a 1 and 40 a 2 . Therefore, as the pressure catching portion 40 b is pressed, the cartridge positioning portion 40 a is reliably pressed upon the cartridge catching portion 82 a (cartridge positioning first portion on main assembly side), being thereby correctly positioned relative to the main assembly 100 a . Incidentally, in this embodiment, the cartridge 7 is provided with the cartridge positioning first and second portions 40 a 1 and 40 a 2 as the cartridge positioning portions on the leading end side. Therefore, it is ensured that the cartridge 7 is more reliably pressed upon the cartridge catching (pressure catching) portion 82 a of the main assembly 100 a . However, the number of the cartridge positioning portions with which the leading end of the cartridge 7 is provided may be only one, as long as it is properly positioned.
[0066] Further, the cartridge 7 is provided with a pushing member 40 c , which is the first pushing member for moving the pressing member 83 into its retreat. With reference to the center of the cartridge 7 , in terms of the horizontal direction perpendicular to the abovementioned cartridge advancement direction, the pushing portion 40 c is located closer to the lengthwise end wall of the cartridge 7 than the pressure catching portion 40 b . The pushing portion 40 c is protruding downstream from the downstream end wall of the cartridge 7 in terms of the cartridge advancement direction, and its end portion is provided with a projection 40 d which is projecting downward. More specifically, the projection 40 d of the pushing portion 40 c is tapered, providing thereby gently slanted surfaces 40 e and 40 f , that is, the slanted surfaces on the downstream and upstream sides, respectively, which are slanted so that their intersection is the peak of the projection 40 d (projection 40 d ).
[0067] Further, the bearing 40 , that is, the bearing on the rear side, is provided with a first contact portion 40 h (cartridge movement regulating first portion of cartridge), which protrudes further upward than the cartridge positioning portion 40 a . The first contact portion 40 h is flat across the top surface (end surface), and is between one end of the cartridge positioning first portion 40 a 1 and the other end of the cartridge positioning second portion 40 a 2 . That is, the first contact surface 40 h is between the cartridge positioning first and second portions 40 a 1 and 40 a 2 ; the cartridge positioning first portion 40 a 1 is located next to one end of the first contact surface 40 h , and the cartridge positioning second portion 40 a 2 is located next to the other end of the first contact surface 40 h . Located on the upstream of the first contact surface 40 h in terms of the cartridge mounting direction is a surface 40 g , which is closer to the axial line of the photosensitive drum 1 than the top surface of the first contact surface 40 h . Further, the bearing 40 , that is, the bearing on the rear end, is provided with a contact surface 40 i , which is the surface for correctly positioning the cartridge 7 in terms of the lengthwise direction of the cartridge 7 . Incidentally, as the cartridge 7 is mounted into the main assembly 100 a , the contact surface 40 i comes into contact with the inward surface of the rear lateral panel of the main assembly 100 a , ensuring that the cartridge 7 is correctly position in terms of the lengthwise direction of the cartridge 7 .
[0068] Next, the bearing 50 (second bearing, that is, bearing which supports other end of photosensitive drum 1 in terms of direction parallel to axial line of photosensitive drum 1 ) will be described. The bearing 50 is the bearing on the front side, that is, the trailing side in terms of the abovementioned cartridge advancement direction. The bearing 50 , that is, the bearing on the front side, is provided with cartridge positioning second portions 50 a ( 50 a 1 and 50 a 2 ), which are two portions of the top side of the peripheral surface of the bearing 50 . More specifically, the cartridge positioning second portions 50 a (portions 50 a 1 and 50 a 2 ) are for correctly positioning the front end of the cartridge 7 relative to the main assembly 100 a , in terms of the direction perpendicular to the abovementioned cartridge advancement direction. They are arcuate in cross section. The cartridge 7 is also provided with an upward pressure catching portion 50 b , which catches the pressure applied to the cartridge 7 by an upwardly pulling member 93 ( FIG. 5 ). The pressure catching portion 50 b is located farther from the axial line of the bearing 50 a than the cartridge positioning first portion 50 a.
[0069] As described above, the cartridge 7 has the first bearing 40 , which supports one of the lengthwise end portions of the photosensitive drum 1 in terms of the direction parallel to the axial line of the photosensitive drum 1 . The contact surface 40 h and cartridge positioning first portions 40 a ( 40 a 1 and 40 a 2 ) are portions of the peripheral surface of the first bearing 40 . Further, the cartridge 7 has the second bearing 50 which supports the other lengthwise end of the photosensitive drum 1 in terms of the direction parallel to the axial line of the photosensitive drum 1 . The contact portion 50 h (contact surface) and cartridge positioning second portions 50 a are portions of the peripheral surface of the second bearing 50 .
[0070] Therefore, it is ensured that the cartridge 7 is precisely positioned relative to the main assembly 100 a.
[0071] Incidentally, like the cartridge positioning portion 40 a , that is, the cartridge positioning portion on the rear side, the cartridge positioning portion 50 a has a cartridge positioning portion (cartridge positioning third portion 50 a 1 ), which is on one side of the axial line of the photosensitive drum 1 , and a cartridge positioning portion (cartridge positioning fourth portion 50 a 2 ), which is on the other side of the axial line of the photosensitive drum 1 . The cartridge positioning third portion 50 a 1 (positioning portion on leading end side) is on the opposite side of the abovementioned axial line I from the cartridge positioning fourth portion 50 a 2 (positioning portion on trailing end side) ( FIG. 15 ). As for the abovementioned pressure catching portion 50 b , it is on the downstream side of the photosensitive drum 1 in terms of the cartridge advancement direction. As seen from the direction K ( FIG. 11( c )) in which upward pressure is applied by the abovementioned upwardly pulling member 93 (pressure applying member, upwardly pushing member), the pressure catching member 50 b is (roughly at the mid point) between the cartridge positioning third and fourth portions 50 a 1 and 50 a 2 . Therefore, as the pressure catching portion 50 b is pressed, the cartridge positioning portions 50 a are reliably pressed upon the pressure catching portion 92 a , being thereby correctly positioned relative to the main assembly 100 a.
[0072] Incidentally, in this embodiment, the cartridge 7 is provided with the cartridge positioning third and fourth portions 50 a 1 a 50 a 2 as the cartridge positioning portions on the trailing end side. Therefore, it is ensured that the cartridge 7 is more reliably pressed upon the pressure catching portions 92 a of the main assembly 100 a . However, the number of the cartridge positioning portions which the trailing end of the cartridge 7 is provided may be only one, as long as it is properly positioned.
[0073] Further, the cartridge 7 is provided with a pushing member 50 c , which is the second pushing member for moving the upwardly pulling member 93 into its retreat. With reference to the center of the cartridge 7 , in terms of the direction which is horizontal and perpendicular to the abovementioned cartridge advancement direction, the pushing portion 50 c is located closer to the lengthwise end wall of the cartridge 7 than the pressure catching portion 50 b . The pushing portion 50 c is protruding downstream from the main portion of the bearing 50 in terms of the cartridge advancement direction, and its end portion is provided with a projection 50 d which is projecting downward. More specifically, the projection 50 d is tapered, providing thereby gently slanted surfaces 50 e and 50 f , that is, the slanted surfaces on the downstream and upstream sides, respectively, which are slanted in such a manner that their intersection is the peak of the projection 50 d (projection 50 d ). Further, the bearing 50 , that is, the bearing on the front side, is provided with a second contact portion 50 h (contact surface, which serves as cartridge movement regulating portion), which protrudes further upward than the cartridge positioning portion 50 a . The second contact portion 50 h is flat across the top surface (second contact surface), and is between one end of the cartridge positioning third portion 50 a 1 and the other end of the cartridge positioning fourth portion 50 a 2 . That is, the second contact surface 50 h is between the cartridge positioning third and fourth portions 50 a 1 and 50 a 2 ; the cartridge positioning third portion 50 a 1 is located next to one end of the second contact surface 50 h , and the cartridge positioning fourth portion 50 a 2 is located next to the other end of the second contact surface 50 h . Located on the upstream of the contact surface 50 h in terms of the cartridge mounting direction is a surface 50 g , which is closer to the axial line of the photosensitive drum 1 than the top surface of the first contact portion 50 h.
[0074] Further, in terms of the direction perpendicular to the axial line of the photosensitive drum 1 , the top surface (area of first contact) of the contact portion 40 h is different in position from the cartridge positioning first portions 40 a ( 40 a 1 and 40 a 2 ). Also in terms of the direction perpendicular to the axial line of the photosensitive drum 1 , the top surface (area of second contact) is different in position from the cartridge positioning second portions 50 a ( 50 a 1 and 50 a 2 ).
[0075] Further, in terms of the above-mentioned cartridge advancement direction, the top surface (area of first contact) of the first contact portion 40 h is on the leading end side, and the top surface (area of second contact) of the second contact portion 50 h is on the trailing end side.
[0076] Therefore, it is ensured that the cartridge 7 is precisely positioned relative to the main assembly 100 a.
[0077] Further in terms of the direction perpendicular to the axial line of the photosensitive drum 1 , the top surface of the contact surface 40 h is between one end of the cartridge positioning portions 40 a ( 40 a 1 and 40 a 2 ) and the other end of the cartridge positioning portions 40 a ( 40 a 1 and 40 a 2 ). Also in terms of the direction perpendicular to the axial line of the photosensitive drum 1 , the top surface (area of contact) of the second contact portion 50 h is between one end of the cartridge positioning second portions 50 a ( 50 a 1 and 50 a 2 ) and the other.
[0078] Therefore, it is ensured that the cartridge 7 is precisely positioned relative to the apparatus main assembly 100 a.
[0079] Next, the structure of the cartridge positioning portion of the main assembly 100 a , and the cartridge pressing mechanism of the main assembly 100 a , will be described. FIG. 5 is a schematic drawing for describing the structure of the cartridge positioning portion of the main assembly 100 a of the image forming apparatus 100 , and the cartridge pressing mechanism of the main assembly 100 a , and show the structures thereof. FIG. 6 is a detailed drawing of the cartridge positioning portion and cartridge pressing mechanism, on the rear side, and shows the structures thereof. FIG. 7 is a detailed drawing of the cartridge positioning portion and cartridge pressing mechanism, on the front side, and shows the structures thereof.
[0080] Referring to FIG. 5 , the main assembly 100 a is provided with a rear lateral panel 82 , which is on the leading end side, in terms of the cartridge mounting direction, and a front lateral panel 92 , which is on the trailing end side. The lateral panel 92 is provided with a hole through which the cartridge 7 is removably mountable in the cartridge bay 22 . The cartridge 7 is inserted into the main assembly 100 a through this hole. Further, the cartridge 7 is inserted into the cartridge bay 22 in the direction of the arrow mark F, along the above described cartridge guiding top guide 80 and cartridge guiding bottom guide 81 ( FIG. 3 ).
[0081] The lateral plate 82 is provided with two cartridge catching portions 82 a ( 82 a 1 and 82 a 2 ), that is, the first portions of the main assembly, which are for correctly positioning the cartridge 7 relative to the main assembly in terms of the direction perpendicular to the direction (advancement direction) in which the cartridge 7 is mounted. The lateral plate 82 is also provided with the pressing member 83 , which is for pressing the cartridge 7 toward the cartridge catching portion 82 a by being under the pressure applied thereto by the resiliency (elastic force) of a compression spring 85 . This pressing member 83 functions as an upwardly pushing member which keeps the cartridge 7 pressed upward by being pressed upward by the pressure applied by the compression spring 85 .
[0082] The pressing member 83 is located under the cartridge catching portion 82 a . It is attached to the lateral plate 82 . More specifically, a shaft 84 solidly fixed to the lateral plate 82 , that is, the lateral plate on the rear side, of the main assembly, is put through the through hole 83 a , the axial line of which coincides with the pivotal axis of the pressing member 83 , so that the pressing member 83 is enabled to take the cartridge pressing position in which it keeps the cartridge 7 pressed on the cartridge catching portions 82 a , position in its retreat in which it does not press on the cartridge 7 , and the standby position in which it remains in the path of the cartridge 7 .
[0083] Further, the pressing member 83 is provided with a cartridge pushing portion 83 b , by which the pressing member 83 pushes the cartridge when the pressing member 83 is in the cartridge pressing position. The cartridge pushing portion 83 b corresponds in position to the pressure catching portion 40 b of the cartridge 7 . The pressing member 83 is also provided with a pressure catching first portion 83 c for moving the pressing member 83 into the retreat. The pressure catching first portion 83 c corresponds in position to the pushing portion 40 c of the cartridge 7 . The pressure catching first portion 83 c is provided with an upward projection 83 d . The upward projection 83 d is provided with gently slanted surfaces 83 e and 83 f , which are the upstream and downstream surfaces of the projection 83 d , respectively, in terms of the cartridge mounting direction. The surfaces 83 e and 83 f are slanted so that the joint between the two surfaces is the peak of the projection 83 d . Further, in terms of the direction perpendicular to the cartridge mounting direction, the pressure catching portion 83 c is located further outward (in terms of the radium direction of hole 83 a ) from the axial line of the hole 83 a than the cartridge pushing portion 83 b . That is, in terms of the lengthwise direction of the pressing member 83 , the abovementioned axial line of the hole 83 a , cartridge pressing portion 83 b , and pressure catching portion 83 c , are positioned in the listed order.
[0084] The lateral plate 82 is provided with a cartridge movement regulating first portion 86 (cartridge movement regulating first portion of main assembly) which prevents the cartridge 7 from moving upward by the reactive force generated as the cartridge pushes the pressing member 83 into its retreat. The cartridge movement regulating first portion 86 is formed of resin, and is located between the two cartridge catching portions 82 a ( 82 a 1 and 82 a 2 ) of the lateral plate 82 .
[0085] Referring to FIG. 7 , the lateral plate 92 is provided with the cartridge insertion hole 92 b , and two cartridge catching portions 92 a ( 92 a 1 and 92 a 2 ), which function as the cartridge positioning second portions of the main assembly. The cartridge catching portions 92 a are two portions of the top portion of the inward surface of the hole 92 b , and are for correctly positioning the cartridge 7 in terms of the direction perpendicular to the cartridge mounting direction. Further, the lateral plate 92 , that is, the frontal lateral plate of the main assembly, is provided with a cartridge pulling member 93 for upwardly pulling the cartridge 7 toward the cartridge catching portions 92 a , by being under the tensional force generated by a pressure application spring 95 , which is a tension spring. The cartridge pulling member 93 is located upward of the cartridge catching portions 92 a . It is pivotally supported by the lateral plate 92 ; a shaft 94 solidly attached to the lateral plate 92 is put though a hole 93 a (whose axial line is rotational axis) of the cartridge pulling member 93 . The cartridge pulling member 93 is attached to (supported by) the lateral plate 92 so that it is enabled to take the position in which it keeps the cartridge 7 pressed upon the cartridge catching portions 92 a , position in its retreat in which it is free from the force from the spring 95 , and standby position in which it is in the path of the cartridge 7 .
[0086] Further, the cartridge pulling member 93 is provided with a cartridge pulling portion 93 b for pulling the cartridge upward when the cartridge pulling member 93 is in the cartridge pulling position. The cartridge pulling portion 93 b corresponds in position to the cartridge pulling force catching portion 50 b of the cartridge 7 . The cartridge pulling member 93 is also provided with a cartridge catching second portion 93 c for moving the cartridge pulling member 93 into its retreat. The cartridge catching second portion 93 c corresponds in position to the pushing portion 50 c of the cartridge 7 . It is provided with an upward projection 93 d , which has gently slanted surfaces 93 e and 93 f ( FIG. 10 ) slanted so that their intersection is the peak of the upward projection 93 d.
[0087] Further, in terms of the direction perpendicular to the cartridge mounting direction, the cartridge catching portion 93 c is located further outward from the axial line of the hole 93 a than the cartridge pulling portion 93 b . That is, in terms of the lengthwise direction of the cartridge pulling member 93 , the hole 93 a , cartridge pulling portion 93 b , and cartridge catching portion 93 c are positioned in the listed order. Further, the lateral plate 92 , that is, the frontal lateral plate of the main assembly, is provided a cartridge movement regulating second portion 96 , which is for preventing the cartridge 7 from being moved upward by the reactive force which occurs as the cartridge pulling member 93 is pushed into its retreat. The cartridge movement regulating portion 96 is between the abovementioned two cartridge catching portions 92 a ( 92 a 1 and 92 a 2 ).
[0088] Incidentally, in this embodiment, on the leading end side of the cartridge 7 in terms of the cartridge mounting direction, the pressure applying member 83 (pressing member, upwardly pushing member) is located below the cartridge catching portion 83 a to press the cartridge upward from below to cause the cartridge 7 to bump into the cartridge catching portions 82 a , whereas on the trailing side of the cartridge 7 in terms of the cartridge mounting direction, the cartridge pulling member 93 (cartridge pressing member) is positioned above the cartridge catching portions 92 a to pull the cartridge 7 upward from above to cause the cartridge to bump into the cartridge catching portions 92 a which are positioned above the cartridge. That is, as the cartridge 7 is moved into its image forming position in the main assembly 100 a , the cartridge catching portion 82 a (portion to be pressed) is pressed by the upward force from the cartridge pushing member 83 . Thus, the cartridge positioning first and second portions 40 a 1 and 40 a 2 (cartridge positioning portions of cartridge, on leading end side) are correctly positioned by the cartridge catching portions 82 a (cartridge positioning first portion of main assembly). Further, the upwardly pulling force catching portion 50 b is pushed by the upwardly pulling force from the upwardly pulling member 93 . Therefore, the cartridge positioning third and fourth portions 50 a 1 and 50 a 2 (cartridge positioning portions of cartridge, on trailing end side) are correctly positioned by the cartridge catching portions 92 a ( 92 a 1 and 92 a 2 ) (cartridge positioning second portions of main assembly). Thus, the employment of this structural arrangement makes it possible to provide the lateral plate 92 , that is, the frontal lateral plate of the main assembly, with the hole through which the cartridge 7 can be mounted into the cartridge bay 22 . Therefore, the bearing 50 , that is, one of the bearings in the adjacencies of the cartridge positioning portion, can be directly pressed. Therefore, the pressure applied to the bearing 50 remains stable. Therefore, the cartridge 7 is precisely positioned and remains precisely positioned. Therefore, the photosensitive drum 1 is precisely placed in contact with the intermediary transfer belt 5 , and remains precisely in contact with the belt 5 .
[0089] Incidentally, this embodiment is not intended to limit the present invention in structural arrangement. That is, the cartridge pressing member 83 and cartridge pulling member 93 may be positioned on the leading and trailing end sides, respectively, as elastically pressing members, in terms of the cartridge mounting direction, or vice versa. In either case, the above described effects can be obtained.
(Operation of Cartridge Pressing Mechanism During Mounting and Removal of Cartridge)
[0090] Next, referring to FIGS. 8-11 , the operations of the cartridge pressing mechanism during the mounting of the cartridge 7 into the image forming apparatus, and the removal of the cartridge 7 from the image forming apparatus, will be described.
(a) Leading End Side: Operations of Cartridge Pressing Mechanism During Mounting and Removal of Cartridge
[0091] FIG. 8 is a plan view of the right-hand side (as seen from front side) of the cartridge pressing rear mechanism of the main assembly. FIG. 9 is a plan view of the rear side of the cartridge pressing rear mechanism (leading end side in terms of cartridge mounting direction) of the main assembly.
[0092] The cartridge 7 is to be mounted in the direction indicated by the arrow mark F as described before. Referring to FIGS. 8( a ) and 9 ( a ), as the cartridge 7 is inserted, the slanted surface 40 e of the pushing portion 40 c of the bearing 40 , that is, the rear bearing of the cartridge 7 , comes into contact with the slanted surface 83 e of the cartridge catching portion 83 c (standby position). Then, as the cartridge 7 is inserted further, the pressing member 83 is gradually pushed down, causing the projection 40 d of the pushing portion 40 c to come into contact with the projection 83 d of the cartridge catching portion 83 c , as shown in FIG. 8( b ). Consequently, the pressing member 83 retreats in the direction indicated by an arrow mark X (position in retreat).
[0093] More specifically, the pressing member 83 moves into the position in its retreat, in which its pressing portion 83 b does not contact the pressure catching portion 40 b of the cartridge 7 , as shown in FIG. 9( b ). Therefore, while the cartridge 7 is mounted, the pressure catching portion 40 b is not subjected to any pressure. The pressure which the cartridge 7 receives from the pressing member 83 when it is mounted is removed by the pushing portion 40 c , which is located further from the hole 83 a . That is, the amount of force necessary to push down the pressing member 83 against the force which acts to upwardly push the cartridge 7 is reduced by the ratio between the distance from the axial line of the hole 83 a to the pressure catching portion 40 b (pushing portion 83 b ) and the distance from the axial line of the hole 83 a to the pushing portion 40 c (pressure catching portion 83 c ). Therefore, the amount of load to which the cartridge 7 is subjected when it is mounted is substantially smaller than the amount of pressure which the cartridge 7 receives from the pressing member 83 ; the amount of force required to mount the cartridge 7 is substantially smaller than the amount of the pressure which the cartridge 7 receives from the pressing member 83 .
[0094] Further, when the cartridge 7 is mounted, the cartridge 7 is subjected to upward force, that is, the reactive force generated as the pressing member 83 is pushed down into its retreat. However, the contacting surface 40 h comes into contact with the cartridge movement regulating portion 86 , that is, the cartridge contacting first portion of the main assembly. Therefore, the cartridge 7 is prevented from moving upward. Here, the cartridge movement regulating portion 86 of the main assembly and the main assembly contacting surface 40 h are positioned so that they remain in contact with each other until immediately before the cartridge positioning portion 40 a is correctly positioned by coming into contact with the cartridge catching portion 83 . Therefore, while the cartridge 7 is mounted, more specifically, from the moment the cartridge 7 begins to receive the upward pressure from the pressing member 83 until immediately before the cartridge 7 is correctly positioned, the cartridge movement regulating portion 86 , that is, the cartridge regulating portion of the main assembly, which is formed of resin, and the contacting surface 40 h , slide on each other, and therefore, the cartridge positioning portion 40 a does not rub against the cartridge catching portion 82 a of the main assembly, which is formed of a thin sheet of steel or the like. Therefore, the problem that the cartridge positioning portion 40 a is shaved by the cartridge catching portion 82 a is prevented.
[0095] As the cartridge 7 is inserted even further, the cartridge catching portion 83 c is disengaged from the pushing portion 40 c , and therefore, the pressing member 83 gradually returns to its pressing position from the retreat. Then, the cartridge 7 is inserted far enough for the contacting surface 40 i , which is for correctly positioning the cartridge 7 in terms of the lengthwise direction of the cartridge 7 , to come into contact with the lateral plate 82 , that is, the rear lateral plate of the main assembly, the pressing portion 83 b comes into contact with the pressure catching portion 40 b , as shown in FIGS. 8( c ) and 9 ( c ), causing the cartridge 7 to be pressed (pressing position) in the direction indicated by an arrow mark J (pressing direction in FIG. 9) . During this process, the cartridge positioning portion 40 a of the cartridge 7 bumps into the cartridge catching portion 82 a of the rear lateral plate 82 of the main assembly, correctly positioning thereby the cartridge 7 in terms of the direction perpendicular to the cartridge mounting direction. Also during this process, the cartridge movement regulating portion 86 of the main assembly becomes disengaged from the contacting surface 40 h ; a preset amount of gap is created between the cartridge movement regulating portion 86 and the surface 40 g (recessed surface). At the same time, the cartridge catching portion 83 c moves past the pushing portion 40 c ; a preset amount of gap is created between the cartridge catching portion 83 c and the recessed surface 40 j.
[0096] As described above, the cartridge pressing mechanism is structured so that the pressing member 83 can be in the standby position, pressing position, and retreat. More specifically, in terms of the top to bottom direction, the standby position, pressing position, and retreat are located in the listed order. Therefore, the pressing member 83 applies a sufficient amount of pressure to the cartridge 7 .
[0097] When removing the cartridge 7 from the main assembly 100 a , the cartridge mounting operation described above is to be carried out in reverse. The pressure which the cartridge 7 receives from the pressing member 83 is removed by the pushing portion 40 c , which is more distant from the axial line of the hole 83 a (rotational axis) than the pressure catching portion 40 b , as it is during the mounting of the cartridge 7 . Therefore, the amount of force necessary for the operation to remove the cartridge 7 in this embodiment is smaller than the amount of force necessary for the operation to remove a cartridge 7 in accordance with the prior art, as it is during the mounting of the cartridge 7 .
[0098] Incidentally, whether mounting the cartridge 7 into the main assembly 100 a , or removing the cartridge 7 from the main assembly 100 a , it is necessary to move the pressing member 83 in the direction perpendicular to the cartridge mounting direction. In this embodiment, however, the projection 83 d of the pressure catching portion 83 c is provided with the gently slanted surfaces on the upstream and downstream sides, one for one, in terms of the cartridge mounting direction. Further, the projection 40 d of the pushing portion 40 c is provided with gently slanted surfaces on the upstream and downstream, one for one, in terms of the cartridge mounting direction. Further, when the cartridge 7 is mounted, the slanted surface 40 e of the pushing portion 40 c comes into contact with the slanted surface 83 e of the pressure catching portion 83 c , whereas when the cartridge 7 is removed, the slanted surface 40 f of the pushing portion 40 c comes into contact with the slanted surface 83 f of the pressure catching portion 83 c . The movement of the pressing member 83 in the direction of the arrow mark X begins under the above described condition. In other words, the cartridge pressing mechanism in this embodiment is structured so that the slanted surfaces of the cartridge 7 remain in contact with the slanted surfaces of the main assembly 100 a while the pressing member 83 moves. Therefore, the cartridge 7 smoothly moves into the main assembly when the cartridge is mounted, and also, smoothly comes out of the main assembly when the cartridge 7 is removed.
(b) Trailing End Side: Operations of Cartridge Pressing Mechanism During Mounting and Removal of Cartridge
[0099] FIG. 10 is a plan view of the left-hand side (as seen from front side) of the cartridge pressing front mechanism of the main assembly. FIG. 11 is a plan view of the front side of the cartridge pressing front (trailing end side in terms of cartridge mounting direction) mechanism of the main assembly.
[0100] As the cartridge 7 is inserted, the slanted surface 50 e of the pushing portion 50 c of the bearing 50 , that is, the front bearing of the cartridge 7 , comes into contact with the slanted surface 93 e of the cartridge catching portion 93 c (standby position), as shown in FIGS. 10( a ) and 11 ( a ). Then, as the cartridge 7 is inserted further, the upwardly pulling member 93 is gradually pushed down, causing the projection 50 d of the pushing portion 50 c to come into contact with the projection 93 d of the cartridge catching portion 93 c , as shown in FIG. 10( b ). Consequently, the upwardly pulling member 93 retreats in the direction indicated by an arrow mark Y (position in retreat). More specifically, the upwardly pulling member 93 retreats into a position in which its upward force applying portion 93 b does not contact the upward force catching portion 50 b of the cartridge 7 , as shown in FIG. 11( b ). Therefore, while the cartridge 7 is mounted, the upward force catching portion 50 b is not subjected to the upward pressure.
[0101] The pressure which the cartridge 7 receives from the upwardly pulling member 93 when it is mounted is removed by the pushing portion 50 c , which is located further from the axial line of the hole 93 a than the upward force catching portion 50 b . That is, the amount of force necessary to push down the upwardly pulling member 93 against the force which acts to upwardly push the cartridge 7 is reduced by an amount equivalent to the ratio between the distance from the axial line of the hole 93 a to the upward force catching portion 50 b (upwardly pulling force applying portion 93 b ) and the distance from the axial line of the hole 93 a to the pushing portion 50 c (upwardly pulling member 93 ). Therefore, the amount of load to which the cartridge 7 is subjected when it is mounted is substantially smaller than the amount of pressure which the cartridge 7 receives from the upwardly pulling member 93 ; the amount of force required to mount the cartridge 7 is substantially smaller than the amount of force which the cartridge 7 receives from the upwardly pulling member 93 .
[0102] Further, when the cartridge 7 is mounted, the cartridge 7 is subjected to upward force, that is, the reactive force generated as the upwardly pulling member 93 is pushed down into its retreat. However, the contacting surface 50 h comes into contact with the cartridge movement regulating portion 96 , that is, the cartridge contacting second portion of the main assembly. Therefore, the cartridge 7 is prevented from moving upward. Here, the cartridge movement regulating portion 96 of the main assembly and the main assembly contacting surface 50 h are positioned so that they remain in contact with each other until immediately before the cartridge positioning portion 50 a is correctly positioned by coming into contact with the cartridge catching portion 92 a . Therefore, while the cartridge 7 is mounted, more specifically, from the moment the cartridge 7 begins to receive the upward force from the upwardly pulling member 93 until immediately before the cartridge 7 is correctly positioned, the cartridge movement regulating portion 96 , that is, the cartridge regulating portion of the main assembly, which is formed of resin, and the cartridge contacting surface 50 h , slide on each other, and therefore, the cartridge positioning portion 50 a does not rub against the cartridge catching portion 92 a of the main assembly, which is formed of a thin sheet of steel or the like. Therefore, the problem that the cartridge positioning portion 50 a is shaved by the cartridge catching portion 92 a is prevented.
[0103] As the cartridge 7 is inserted even further, the cartridge catching portion 93 c is disengaged from the pushing portion 50 c , and therefore, the upwardly pulling portion 93 gradually returns to the upwardly pulling position from the retreat. Then, the cartridge 7 is inserted far enough for the contacting surface 50 i , which is for correctly positioning the cartridge 7 in terms of the lengthwise direction of the cartridge 7 , to come into contact with the lateral plate 82 , that is, the rear lateral plate of the main assembly, the upwardly pulling portion 93 b comes into contact with the cartridge catching portion 50 b , as shown in FIGS. 10( c ) and 11 ( c ), causing the cartridge 7 to be pressed (pressing position) in the direction indicated by an arrow mark K (upwardly pulling direction in FIG. 11) . During this process, the cartridge positioning portion 50 a of the cartridge 7 bumps into the cartridge catching portion 92 a of the frontal lateral plate 92 of the main assembly, correctly positioning thereby the cartridge 7 in terms of the direction perpendicular to the cartridge mounting direction. Also during this process, the cartridge movement regulating portion 96 of the main assembly becomes disengaged from the contacting surface 50 h ; a preset amount of gap is created between the cartridge movement regulating portion 96 and the recessed surface 50 g . At the same time, the cartridge catching portion 93 c moves past the pushing portion 50 c ; a preset amount of gap is created between the cartridge catching portion 93 c and the recessed surface 50 j.
[0104] As described above, the cartridge pressing mechanism is structured so that the upwardly pulling member 93 is enabled to move into the standby position, upwardly pulling (pressing) position, and retreat. More specifically, in terms of the top to bottom direction, the standby position, upwardly pulling (pressing) position, and retreat are located in the listed order. Therefore, the upwardly pulling member 93 applies to the cartridge 7 a sufficient amount of pressure for pulling up the cartridge 7 .
[0105] When removing the cartridge 7 from the main assembly 100 a , the cartridge mounting operation described above is to be carried out in reverse. The upward force which the cartridge 7 receives from the upwardly pulling member 93 is removed by the pushing portion 50 c , which is more distant from the axial line of the hole 93 a (rotational axis of pulling member 93 ) than the upward force catching portion 50 b , as it is during the mounting of the cartridge 7 . Therefore, the amount of force necessary for the operation to remove the cartridge 7 in this embodiment is significantly smaller than the amount of force necessary for the operation to remove a cartridge 7 in accordance with the prior art, as the amount of the force necessary for the operation to mount the cartridge 7 in this embodiment is significantly smaller than the amount of force necessary for the operation to mount a cartridge in accordance with the prior art.
[0106] Incidentally, whether mounting the cartridge 7 into the main assembly 100 a , or removing the cartridge 7 from the main assembly 100 a , it is necessary to move the upwardly pulling member 93 in the direction perpendicular to the cartridge mounting direction. In this embodiment, however, the projection 93 d of the pressure catching portion 93 c is provided with the gently slanted surfaces, which are on the upstream and downstream sides, one for one, in terms of the cartridge mounting direction. Further, the projection 50 d of the pushing portion 50 c is provided with gently slanted surfaces, which are on the upstream and downstream, one for one, in terms of the cartridge mounting direction. Thus, when the cartridge 7 is mounted, the slanted surface 50 e of the pushing portion 50 c comes into contact with the slanted surface 93 e of the pressure catching portion 93 c , whereas when the cartridge 7 is removed, the slanted surface 50 f of the pushing portion 50 c comes into contact with the slanted surface 93 f of the pressure catching portion 93 c . It is under this condition that the movement of the upwardly pulling member 93 in the direction of the arrow mark Y begins. In other words, the cartridge pressing mechanism in this embodiment is structured so that the slanted surfaces of the cartridge 7 remain in contact with the slanted surfaces of the main assembly 100 a while the upwardly pulling member 93 moves. Therefore, the cartridge 7 smoothly moves into the main assembly when the cartridge is mounted, and also, smoothly comes out of the main assembly when the cartridge 7 is removed.
[0107] Incidentally, when the cartridge 7 is mounted or removed, the operation of the cartridge pressing mechanism in this embodiment occurs on the leading and trailing end sides, in terms of the cartridge mounting direction, roughly at the same time. Further, the direction in which the pressing member 83 , that is, the rear pressing member, is rotated is opposite from the direction in which the pressing member 93 (upwardly pulling member), that is, the front pressing member, is rotated.
[0108] To describe in more detail, referring to FIGS. 12( a ) and 12 ( b ), on the leading end side in terms of the direction perpendicular to the cartridge mounting direction, the axial line of the hole 83 a is on the left side of Line L, which coincides with the axial line of the photosensitive drum 1 and extends in the direction parallel to the direction in which the cartridge 7 is moved to be correctly positioned, and the pressure catching portion 83 c is on the right side of Line L. On the other hand, on the trailing end side, the axial line of the hole 93 a is on the right-hand side of the abovementioned Line L, and the pressure catching portion 93 c is on the left-hand side of Line L; the positional relationship between the hole and pressure catching portion of the pressing portion on the leading end side is opposite to that on the trailing end side.
[0109] That is, the pressing member 83 , which is on the rear side of the main assembly, is rotated in the direction indicated by an arrow mark M when it is moved into the retreat, whereas the upwardly pulling member 93 , which is on the front side of the main assembly, is rotated in the direction indicated by an arrow mark N when it is moved into the retreat. Therefore, the loads from the pressing members 83 and 93 , that is, the pressing members on the rear and front sides of the main assembly, to which the pushing portions 40 c and 50 c are subjected when the cartridge 7 is mounted or removed, act in the directions indicated by arrow marks P 1 and P 2 , respectively, in FIGS. 12( a ) and 12 ( c ). The angles of the directions P 1 and P 2 of these loads are preset relative to Line L, which extends in the direction in which the cartridge is pushed up. Further, the abovementioned angles are roughly symmetrical with reference to Line L, which extends in the direction parallel to the directions P 1 and P 2 of the load, that is, the direction in which the cartridge 7 is upwardly pushed, as shown in FIG. 12( c 0 . Therefore, when the cartridge 7 is mounted or removed, its remains stable in attitude, being therefore significantly better in operability than a cartridge in accordance with the prior art.
(Structural Arrangement for Preventing Shaving of Cartridge Positioning Portion of Cartridge)
[0110] The cartridge 7 in this embodiment is prevented from being shaved across its cartridge positioning portion when it is mounted into, or removed from, the main assembly 100 a . This embodiment can reduce the problem that when the cartridge 7 is mounted into the main assembly 100 a , the cartridge positioning first and second portions (portions 40 a and 50 a ) of the cartridge 7 rub against the corresponding portions (members) of the main assembly 100 a . Further, this embodiment can reduce the problem that when the cartridge 7 is mounted into the main assembly 100 a , the abovementioned cartridge positioning first and second portions are placed in contact with the corresponding portions (members) of the main assembly 100 a.
[0111] That is, as described above, the bearings 40 and 50 , that is, the bearings on the leading and trailing end sides, in terms of the cartridge mounting direction, are provided with the contacting portions 40 h and 50 h , which protrude upward beyond the cartridge positioning portions 40 a and 50 a , which also are the portions of their peripheral surfaces. These contacting portions 40 h and 50 h are flat across the top surface, and positioned on one side of the cartridge positioning portion of the cartridge 7 , and the other, respectively.
[0112] As the cartridge 7 is inserted into the main assembly 100 a structured as described above, the cartridge 7 is subjected to the upward force, that is, the reactive force generated as the pressing member 83 , that is, the cartridge pressing rear member, and the upwardly pulling member 93 , that is, the cartridge pressing front member, are pushed downward into their retreats. During this process, the contacting portion 40 h (surface) comes into contact with the cartridge movement regulating portion 86 , that is, the cartridge contacting first portion of the main assembly, and the contacting portion 50 h (surface) comes into contact with the cartridge movement regulating portion 96 , that is, the cartridge contacting second portion of the main assembly. Therefore, the cartridge 7 is prevented from moving upward.
[0113] Here, the cartridge pressing mechanism is structured so that the cartridge movement regulating portion 86 , that is, the cartridge movement regulating portion of the main assembly, which is on the rear side of the main assembly, and the contacting portion 40 h (surface) remain in contact with each other until immediately before the cartridge positioning portion 40 a is correctly positioned by coming into contact with the cartridge catching portion 82 a . Similarly, the cartridge movement regulating portion 96 , that is, the cartridge movement regulating portion of the main assembly, which is on the front side of the main assembly, and the contacting portion 50 h (surface) remain in contact with each other until immediately before the cartridge positioning portion 50 a is correctly positioned by coming into contact with the cartridge catching portion 92 a.
[0114] Therefore, while the cartridge 7 is mounted, more specifically, from the moment the cartridge 7 begins to receive the upward force from the pressing member 83 and upwardly pulling member 93 until immediately before the cartridge 7 is correctly positioned, the cartridge movement regulating portions 86 and 96 , that is, the cartridge regulating portions of the main assembly, which is formed of resin, and the cartridge contacting surfaces 40 h and 50 h , slide on the cartridge movement regulating portions 86 and 96 , respectively, and therefore, the cartridge positioning portions 40 a and 50 a , which are on the rear and front sides, do not rub against the cartridge catching portions 82 a and 92 a of the main assembly, which are formed of a thin sheet of steel or the like. Therefore, the problem that the cartridge positioning portions 40 a and 50 a are shaved by the cartridge catching portions 82 a and 92 a is prevented.
[0115] As described above, the cartridge pressing mechanism is structured so that the cartridge 7 is mounted or removed while cancelling the cartridge pressing force by the pressure applied to the point of the pressing member, which is farther from the portion of the pressing member, by which the pressing member presses on the cartridge 7 . Therefore, the amount of force necessary to mount or remove the cartridge 7 is sufficiently small relative to the amount of force (pressure) which the cartridge 7 receives from the pressing member. Thus, the amount of force required to mount the cartridge 7 , that is, the cartridge in this embodiment, into the main assembly of the image forming apparatus in this embodiment, or remove the cartridge 7 from the image forming apparatus in this embodiment, is significantly smaller than that required to mount a cartridge in accordance with the prior art into the main assembly of an image forming apparatus in accordance with the prior art, or removing the cartridge in accordance with the prior art from the main assembly of the image forming apparatus in accordance with the prior art. In other words, the present invention can provide a cartridge and an image forming apparatus, which are significantly better in operability in terms of the mounting of the cartridge.
[0116] Further, when mounting the cartridge 7 into the main assembly 100 a , or removing the cartridge 7 from the main assembly 100 a , the cartridge positioning members are prevented from being shaved. Therefore, it is ensured that the cartridge 7 is correctly positioned.
[0117] Incidentally, the structure of the image forming apparatus in this embodiment is such that the cartridges are juxtaposed side by side (in parallel) in a horizontal straight row, and also, that the intermediary transfer unit is disposed on the top side of the cartridges so that the cartridges can be pressed upward from below by the pressing members. However, this embodiment is not intended to limit the present invention in terms of image forming apparatus structure. For example, the present invention is also applicable to an image forming apparatus structured so that its intermediary transfer unit is on the under side of the cartridges, and the cartridges are pressed downward from above by the pressing member (pressuring member). In the case of such a structural arrangement, the photosensitive drum 1 is placed in contact with the intermediary transfer belt 5 by applying downward pressure to the cartridge 7 .
[0118] In the case of an image forming apparatus, such as the one in this embodiment, which is structured so that the cartridges are pressed from below, the amount of force necessary to press a cartridge to correctly position the cartridge needs to be set in consideration of the weight of the cartridge itself. Therefore, it must be greater than the amount of force necessary to press a cartridge in an image forming apparatus structured so that the cartridge is pressed from above, and so is the amount of force necessary to push down the pressing member. Thus, the effects of the present invention can be further enhanced by structuring the image forming apparatus so that the cartridge can be mounted or removed while cancelling the pressure applied to the cartridge by the cartridge pressing portion of the cartridge pressing member, by the portion of the cartridge pressing member, which is farther from the rotational axis of the cartridge pressing member than the cartridge pressing portion of the cartridge pressing member.
[0119] Also in this embodiment, it is on both the leading and trailing end sides of the cartridge, in terms of the cartridge mounting direction, that the force from the cartridge pressing member (inclusive of upwardly pulling member) is cancelled by the portion of the cartridge pressing member, which is farther from the axial line the pressing member than the cartridge pressing portion of the pressing member while the cartridge is mounted or removed. However, this embodiment is not intended to limit the present invention in scope in terms of the structure of an image forming apparatus. For example, an image forming apparatus may be structured so that only one end of the image forming apparatus, that is, either the leading or trailing end in terms of the cartridge mounting direction, is provided with the cartridge pressing member. However, an image forming apparatus having the pressing member on both the leading and trailing end in terms of the cartridge mounting direction is smaller in the total amount of force necessary to mount or remove the cartridge than an image forming apparatus having the cartridge pressing member on only the leading or trailing end in terms of the cartridge mounting direction. Also as described above, by structuring an image forming apparatus so that the cartridge pressing member on the rear side, and the cartridge pressing member (cartridge pulling member) on the front side, are symmetrical with respect to the direction in which the load from the pressing member is pushed up, it is possible to keep the cartridge 7 stable in attitude when mounting or removing the cartridge 7 , enhancing further the effects of this embodiment of the present invention.
Embodiment 2
[0120] Next, referring to FIGS. 13 and 14 , the second embodiment of the present invention will be described. By the way, this embodiment is the same in the basic structure of an image forming apparatus as the first embodiment described above. Therefore, this embodiment will be described regarding only the structural features different from those in the first embodiment to avoid the repetition of the same description. Further, the members, portions, etc., of the image forming apparatus in this embodiment, which are the same in function as those in the first embodiment described above, are given the same referential symbols.
[0121] FIG. 13 is an external perspective view of the cartridge in this embodiment. FIG. 14 is a schematic perspective view of the cartridge positioning member and cartridge pressing member on the rear side of the main assembly of the image forming apparatus, showing their structures.
[0122] The image forming apparatus in the first embodiment was structured so that the bearing of the cartridge 7 , which is on the leading end, in terms of the direction in which the cartridge 7 is mounted into the main assembly of the image forming apparatus, is provided with the pressing member 83 having the pushing portion 83 c for pushing down the cartridge 7 . In this embodiment, the image forming apparatus structured so that the pushing portion for pushing down the pressing member is a part of the development unit, will be described.
[0123] Referring to FIG. 12 , it is the development unit 4 that is provided with a pressing member pushing portion 140 c , which is for moving the pressing member into its retreat. The pushing portion 140 c protrudes downstream from the downstream end of the cartridge 7 in terms of the cartridge mounting direction. The end portion of the pushing portion 140 c is provided with a projection 140 d , which projects downward. The projection 140 d is provided with two surfaces 140 e and 140 f , which are gently slanted so that the intersection of the two surfaces is the peak of the projection 140 d . In terms of the direction perpendicular to the cartridge mounting direction, the pushing portion 140 c is on the opposite side of the pressure catching portion 40 b from the axial line of the hole 183 a ( FIG. 14 ) of the cartridge pressing member 183 (pressure applying member), which will be described later. Further, the pushing portion 140 c is located farther from the axial line of the hole 183 a than the pressure catching portion 40 b.
[0124] Referring to FIG. 14 , as for the main assembly 100 a , it is provided with the cartridge pressing member 183 , which is for pressing the cartridge 7 toward the cartridge catching portion 82 a (pressure catching portion). The pressing member 183 is located below the cartridge catching portion 82 a . The pressing member 183 is attached to the lateral plate 82 , that is, the lateral plate of the main assembly on the rear side; the shaft 84 solid attached to the lateral plate 82 is put through the hole 183 a of the pressing member 183 so that the pivotal axis of the pressing member 183 coincides with the axial line of the hole 183 a . Further, the pressing member 183 is rotatably attached to the lateral plate 82 so that it is rotatably movable to the cartridge pressing position, in which it presses the cartridge 7 upon the cartridge catching portion 82 a , and the retreat into which it is moved to remove the pressure which it applies to the cartridge 7 .
[0125] Further, the pressing member 183 is provided with a pressing portion 183 b , which presses on the cartridge 7 when the pressing member 183 is in the pressing position. The pressing portion 183 b corresponds in position to the pressure catching portion 40 b of the cartridge 7 . The pressing member 183 is also provided with a pressure catching portion 183 c , which is for moving the pressing member 183 into the retreat. The pressure catching portion 183 c corresponds in position to the pushing portion 140 c of the cartridge 7 .
[0126] The pressure catching portion 183 c is provided with an upward projection 183 d , which has two surfaces 183 e and 183 f . The surfaces 183 e and 183 f are on the downstream and upstream sides, respectively, in terms of the cartridge mounting direction, and are gently slanted so that their intersection is the peak of the projection 183 d.
[0127] In terms of the direction perpendicular to the cartridge mounting direction, the pressure catching portion 183 c is on the opposite side of the pressing portion 183 b from the axial line of the hole 183 a . Further, the pressure catching portion 183 c is located farther from the axial line of the hole 183 a than the pressing portion 183 b.
[0128] Next, the movement of the components of the cartridge pressing mechanism in this embodiment, which occur when the cartridge 7 is mounted into the image forming apparatus 100 , will be described. FIG. 16 is a plan view of the cartridge pressing rear mechanism, as seen from the left side (as seen from front side of image forming apparatus) of the main assembly of the image forming apparatus, and shows the operation of the cartridge pressing member, which occurs when the cartridge 7 is mounted into the main assembly 100 . FIG. 17 is a plan view of the cartridge pressing rear mechanism, as seen from the leading end side of the cartridge 7 in terms of the cartridge mounting direction, and shows the operation of the pressing member.
[0129] The cartridge 7 is mounted in the direction indicated by an arrow mark F shown in FIG. 16( a ). Referring to FIGS. 16( a ) and 17 ( a ), as the cartridge 7 is inserted, the slanted surface 140 e of the pushing portion 140 c of the development unit 4 comes into contact with the slanted surface 183 e of the cartridge catching portion 183 c (standby position). Then, as the cartridge 7 is inserted further, the pressing member 183 is gradually pushed down, causing the projection 140 d of the pushing portion 140 c to come into contact with the projection 183 d of the cartridge catching portion 183 c , as shown in FIG. 16( b ). Consequently, the pressing member 183 retreats in the direction indicated by an arrow mark T (position in retreat). More specifically, the pressing member 183 retreats into the position (position in retreat) in which its pressing portion 183 b does not contact the pressure catching portion 140 b of the cartridge 7 , as shown in FIG. 17( b ). Therefore, while the cartridge 7 is mounted, the pressure catching portion 140 b is not subjected to any pressure. The pressure which the cartridge 7 receives from the pressing member 183 when it is mounted is cancelled by the pushing portion 140 c , which is located further from the rotational axis of the pressing member 183 , which coincides with the axial line of the hole 183 a . That is, the amount of force necessary to push down the pressing member 183 against the force which acts to upwardly pushing the cartridge 7 is reduced by the ratio between the distance from the axial line of the hole 183 a to the pressure catching portion 140 b (pushing portion 183 b ) and the distance from the axial line of the hole 183 a to the pushing portion 140 c (pressure catching portion 183 c ). Therefore, the amount of load to which the cartridge 7 is subjected when it is mounted is substantially smaller than the amount of pressure which the cartridge 7 receives from the pressing member 183 ; the amount of force required to mount the cartridge 7 is substantially smaller than the amount of the pressure required to mount a cartridge ( 7 ) in accordance with the prior art.
[0130] Further, when the cartridge 7 is mounted, the cartridge 7 is subjected to upward force, that is, the reactive force generated as the pressing member 183 is pushed down into its retreat. However, the contacting surface 40 h comes into contact with the cartridge movement regulating portion 86 , that is, the cartridge contacting first portion of the main assembly. Therefore, the cartridge 7 is prevented from being moved upward. Here, the cartridge movement regulating portion 86 of the main assembly and the main assembly contacting second surface 40 h of the cartridge 7 are positioned so that they remain in contact with each other until immediately before the cartridge positioning portion 40 (a pressure catching portion) is correctly positioned by coming into contact with the cartridge catching portion 82 a . Therefore, while the cartridge 7 is mounted, more specifically, from the moment the cartridge 7 begins to receive the upward pressure from the pressing member 183 until immediately before the cartridge 7 is correctly positioned, the cartridge movement regulating portion 86 , that is, the cartridge movement regulating portion of the main assembly, which is formed of resin, and the contacting surface 40 h , slide on each other, and the pressure catching portion 40 a (cartridge positioning portion of cartridge) does not rub against the cartridge catching portion 82 a of the main assembly, which is formed of a thin sheet of steel or the like. Therefore, the problem that the cartridge positioning portion 40 a is shaved by the cartridge catching portion 82 a is prevented.
[0131] As the cartridge is inserted even further, the cartridge catching portion 183 c is disengaged from the pushing portion 140 c , and therefore, the pressing member 183 gradually returns to the pressing position from the retreat. Then, the cartridge 7 is inserted far enough for the contacting surface 40 i , which is for correctly positioning the cartridge 7 in terms of the lengthwise direction of the cartridge 7 , to come into contact with the lateral plate 82 , that is, the rear lateral plate of the main assembly, the pressing portion 183 b comes into contact with the pressure catching portion 40 b , as shown in FIGS. 16( c ) and 17 ( c ), causing the cartridge 7 to be pressed (pressing position) in the direction indicated by an arrow mark S (pressing direction). During this process, the cartridge positioning portion 40 a of the cartridge 7 bumps into the cartridge catching portion 82 a of the rear lateral plate 82 of the main assembly, correctly positioning thereby the cartridge 7 in terms of the direction perpendicular to the cartridge mounting direction. Also during this process, the cartridge movement regulating portion 86 of the main assembly becomes disengaged from the second contacting surface 40 h ; a preset amount of gap is provided between the cartridge movement regulating portion 86 and the surface 40 g (recessed surface). At the same time, the cartridge catching portion 183 c moves past the pushing portion 140 c ; a preset amount of gap is provided between the cartridge catching portion 183 c and the recessed surface 140 j.
[0132] Also in this embodiment, the pressing member 183 is enabled to apply a sufficient amount of pressure to the cartridge 7 .
[0133] When removing the cartridge 7 from the main assembly 100 a , the cartridge mounting operation described above is to be carried out in reverse. The upward force which the cartridge 7 receives from the pressing member 183 is cancelled by the pushing portion 140 c , which is located farther from the axial line of the hole 183 a , as it is during the mounting of the cartridge 7 . Therefore, the amount of force necessary for the operation to remove the cartridge 7 in this embodiment is significantly smaller than the amount of force necessary for the operation to remove a cartridge 7 in accordance with the prior art, as the amount of the force necessary for the operation to mount the cartridge 7 in this embodiment is significantly smaller than the amount of force necessary for the operation to mount a cartridge in accordance with the prior art.
[0134] Further, as the cartridge catching portion 82 a of the main assembly becomes disengaged from the pressure catching portion 40 a (cartridge positioning portion of cartridge), the cartridge movement regulating portion 86 of the main assembly comes into contact with the second contacting surface 40 h . Further, even during the removal of the cartridge 7 , the cartridge movement regulating portion 86 of the main assembly, which is formed of resin, and the second contacting surface 40 h , slide against each other, preventing thereby the pressure catching portion 40 a from rubbing against the cartridge catching portion 82 a of the lateral plate of the main assembly, as long as the cartridge 7 is under the upward force applied by the pressing member 183 . Therefore, the problem that the pressure catching portion 40 a (cartridge positioning portion of cartridge) is shaved by the cartridge catching portion 82 a as it rubs against the cartridge catching portion 82 a is prevented.
[0135] In this embodiment, only the portion of the development unit 4 , which corresponds in position to the rear end side of the main assembly of the image forming apparatus, is provided with the pushing portion. However, it may be only the front end of the development unit that is provided with the pushing portion. The effects of providing only the front end of the development unit with the pushing portion are the same as that achievable by providing only the rear end of the development unit with the pushing portion.
[0136] While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth, and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.
[0137] This application claims priority from Japanese Patent Applications Nos. 331309/2006 filed Dec. 8, 2006, and 266399/2007 filed Oct. 12, 2007, which are hereby incorporated by reference. | A process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus. The cartridge includes a drum, first and second guidable portions guidable by first and second guides when the cartridge enters or advances in the main assembly, first and second regulatable portions provided at leading and trailing sides of the cartridge with respect to the advancing direction and regulated by a first main assembly regulator when the process is advancing in the main assembly, and first and second positionable portions to be positioned at first and main assembly second positioners, respectively, by the urging force of a main assembly urging member after the first and second regulatable portions pass the first and second regulators, respectively. The cartridge is mounted to the main assembly with the first and second positionable portions at the first and second positioners, respectively, by the urging force of the urging member. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a micro-evaporator according to the preamble of claim 1
2. Description of Related Art
Micro-evaporators are used to evaporate liquid media such as water, alcohols or alcohol/water mixtures, liquid gases or liquid alkanes for further processing. Such micro-evaporators are for example used in the fields of fuel cell engineering.
Different designs of evaporators are known. So-called plate heat exchangers consist of corrugated steel plates provided with channels for transferring the liquid like filter presses. Resistant rubber seals hold the plates at a distance from each other and seal the channels of the two fluids from each other. Due to the rubber seals, the plate heat exchangers are restricted to a maximum temperature of 250° C. The two fluids flow in a concurrent or a countercurrent flow as thin layers alternating up or down through a series of chambers and contact each other on both chamber walls. Corrugated plate profiles increase turbulence and improve the transfer of heat. Such evaporators are not compact and, when they are operated with heating gas, they have low power densities. Such plate heat transfer systems are for example known from Vauck/Muller; Grundoperationen der Verfahrenstechnik; Leipzig 1994.
An evaporator with micro-structured components for the partial or complete evaporation of liquids is for example known from U.S. Pat. No. 6,126,723. The reactor consists of two fluid chambers for a first and second fluid, and the fluid chambers are connected by means of plates that are porous or provided with micro-structured holes. The reactor is intended for transferring a working fluid contained in a first liquid into a second fluid, and the plates provided with micro-structured holes are only permeable to the working fluid. This reactor can also be used as an evaporator.
Micro-structured devices for conducting media are known from DE 199 63 594 A1 and DE 100 10 400 C2. These devices are especially suitable for evaporating liquid media.
The device in DE 199 63 594 A1 has a layered structure, and at least one layer possesses a number of micro-channels through which the medium to be evaporated flows. A second layer also has a number of micro-channels through which a heat-transferring medium flows. The micro-channels each have an inlet and outlet. To satisfactorily evaporate the liquid medium, the outlets of the micro-channels have a smaller area for the medium to be evaporated and/or have a different geometrical structure than the respective inlets. The pressure of the liquid medium is thereby increased in the micro-channels so that overheated, still-liquid medium suddenly transitions from a liquid to a vapor after leaving the smaller area outlets.
According to DE 100 10 400 C2, the heat output of the heating device is adjustable at least in areas independent of other areas to adjust a desired temperature profile on the surface of the flow channels, at least in individual areas of the flow channels in the direction of flow.
According to this state-of-the-art, the micro-channels for guiding the liquid to be evaporated are parallel. The disadvantage of this micro-evaporator is that the vapor bursts or vapor bubbles can arise if the optimum temperature range is not adjusted. The optimum operating point must be maintained which requires several parameters to be harmonized such as the flow speed and pressure of the medium to be evaporated, the heat output, etc. Such micro-evaporators therefore malfunction easily and cannot be flexibly used.
The problem of the invention is to provide a micro-evaporator that is easier to handle and can be operated problem-free over a wider temperature range
BRIEF SUMMARY OF THE INVENTION
This problem is solved with a micro-evaporator where the micro-evaporator channels are in a trapezoidal area having an inlet area with a smaller cross-section ending in the feed chamber, and an outlet area with a larger cross-section ending in the vapor collection chamber.
By arranging the micro-evaporator channels in a trapezoidal area, the inlets of the micro-channels lie directly next to each other. The width of segments separating the micro-evaporator channels can become 0 at the inlet area of the trapezoidal area. The liquid in the feed chamber is therefore discharged very quickly which effectively prevents premature evaporation in the feed chamber.
The outlet area of the trapezoidal area is larger than the inlet area with the advantage that the outlets of the micro-channels are clearly spaced which allows the (overheated) vapor whose volume is very much more than that of the initial liquid to exit unrestricted into the corresponding large-volume vapor collection chamber. This prevents overpressure at the outlet area and keeps the liquid columns from being pressed back in the micro-channels opposite the direction of flow which enhances problem-free operation.
It has been demonstrated that the micro-evaporator can operate smoothly over a wide temperature range of 100 to 500° C. for water. The micro-evaporator is insensitive to parameter changes, and a change in the mass flow of the medium to be evaporated is not problematic at a given heating temperature.
Another advantage of the micro-evaporator is that it can be positioned independently in use.
The substantial compactness and the high energy density are additional advantages. In addition, the system can be operated free of carrier gas. The system can be heated with heating gas whose temperature can lie several hundred degrees centigrade above the boiling temperature of the liquid to be evaporated. Furthermore, a chemical reaction can be used for heating whose reaction temperature can lie several hundred degrees centigrade above the boiling temperature of the liquid to be evaporated. The liquid can also be evaporated at heating temperatures that are slightly above the evaporation temperature of the medium to be evaporated, which is advantageous in regard to energy consumption.
The micro-evaporator can be operated within a variable pressure range of the liquid to be evaporated.
The micro-evaporator channels are preferably located in the trapezoidal area in a fan-like arrangement. This means that the micro-evaporation channels lead radially from the liquid feed chamber and enter the vapor collection chamber at a marked distance from each other.
The micro-evaporator channels preferably have a cross-section of 100 μm 2 to 0.01 mm 2 . The cross-sectional areas are more preferably 100 μm 2 to 0.005 mm 2 and 100 μm 2 to 0.0025 μm 2 . Rectangular micro-evaporator channels have corresponding edge lengths of 10 μm to 100 μm, or a especially range from 10 μm to 50 μm. Due to the small dimensions of the micro-evaporator channels, the contact surface/volume ratio is very high, and a high transfer of heat is achieved that causes the liquid to quickly evaporate. These small dimensions of the micro-evaporator channels, especially in the area where the liquid/gas transition occurs, prevent boiling delays which enables the liquid to evenly evaporate.
The micro-evaporator channels preferably have a constant cross-section over their entire length. The micro-evaporator channels can for example be produced by electrical discharge machining, molding, laser ablation or other processing methods.
The micro-evaporator channels can run in a straight line or meander. The advantage of meandering or wave-shaped micro-evaporator channels is the greater contact between the liquid to be evaporated and the channel wall while the liquid is flowing due to the curves in the channel. This substantially improves the transfer of heat. Another advantage of the meandering arrangement and design of the micro-evaporator channels is that, despite the greater length of the micro-evaporator channels, the design can be more compact.
In another embodiment, the micro-evaporator channels have sections with larger and smaller cross-sections that alternate sequentially. This embodiment of the micro-evaporator channels also has the advantage of greater heat transfer from the increased contact of the liquid due to the necessary diversion in the micro-evaporator channels.
In these embodiments of the micro-evaporator channels, the distance between the micro-evaporator channels increases toward the vapor collection chamber.
An alternate embodiment provides that each micro-evaporator channel consists of offset, sequential channel sections. In a development of this embodiment, the adjacent channel sections can be connected with each other. Consequently, the volume available for the vapor in the area of the micro-evaporator channels increases toward the vapor collection chamber. This takes into account the increased volume of the vapor and helps the (overheated) vapor to be quickly discharged into the vapor collection chamber.
The vapor collection chamber preferably has a larger volume than the liquid feed chamber.
The means to heat the liquid to be evaporated are preferably located at least in the area above and/or below the micro-evaporator channels. By means of this arrangement, the area to be heated can be preferably concentrated on the area where the micro-evaporator channels are located. Given the relatively fast discharge of the liquid to be evaporated out of the feed chamber into the micro-evaporator channels, the entire micro-evaporator does not necessarily have to be correspondingly heated.
The means for heating preferably comprise micro-structured heating channels, electrical heating cartridges or lamps such as quartz lamps. In this case, the heat is provided by radiation energy.
A preferred embodiment of the micro-evaporator is characterized by at least one evaporator plate, on the front side comprising the structure of the liquid supply chamber, the micro-evaporator channels and vapor collection chamber. The essential components can therefore be located in a plate which simplifies the production of the micro-evaporator and also allows for a modular design in which numerous such plates can be stacked, and the evaporation plates are only separated from each other by simple, preferably non-structured intermediate plates.
When the evaporator plate preferably has micro-structured heating channels in its back, it additionally contributes to the compact design and simplified production of the micro-evaporator.
The cross-sections of the heating channels preferably range from 0.1 mm to 10 mm.
The heating channels can be coated with a catalyst material. The heating in this instance can be provided by catalytic combustion.
The heating channels are preferably parallel, and preferably extend in the same direction as the micro-evaporator channels. This same alignment of the heating channels means that both the heating channels as well as the micro-evaporator channels extend essentially in the lengthwise direction of the plate. The heating channels can be operated in a concurrent flow or in a counter-current flow with reference to the direction of flow of the liquid to be evaporated. This depends on the heating liquid, the liquid to be evaporated and the required transfer of heat.
The residual wall thickness of the evaporator plate is preferably <1 mm. The advantage is that there is a good transfer of heat between the heating medium and the liquid to be evaporated.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. Exemplary embodiments of the invention are further explained below with reference to the drawings. The following are shown:
FIG. 1 an exploded view of a micro-evaporator in a first embodiment,
FIG. 2 a plan view of a micro-evaporator plate of the micro-evaporator shown in FIG. 1 ,
FIG. 3 a - c enlarged sections from the plan view of the micro-evaporator shown in FIG. 2 ,
FIG. 4-7 enlarged sections of a schematic representation of the micro-evaporator plate to illustrate different embodiments of the micro-evaporator channels,
FIG. 8 a perspective view of the underside of an evaporator plate
FIGS. 9 a and b perspective plan and bottom views of a micro-evaporator in another embodiment, and
FIG. 10 a schematic representation of an evaporator system using a micro-evaporator according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a micro-evaporator 1 having (from top to bottom) a heating plate 2 with holes 3 to receive heating elements 4 , a cover plate 5 , a micro-evaporator plate 10 and a baseplate 6 . The cover plate 5 lies on the micro-evaporator plate 10 that has the micro-structured micro-evaporator channels in a trapezoidal area 15 as explained in detail with reference to the subsequent Figures.
The micro-evaporator plate 10 where the liquid is evaporated is connected to a feed line 30 for the liquid to be evaporated and a discharge line 31 to remove the vapor. The micro-evaporator plate 10 is in a groove-like recess 8 of the base plate 6 . Overall, this yields a cuboid micro-evaporator with outer dimensions less than 50 mm that is expandable with additional micro-evaporator plates 10 and inserted intermediate plates 7 as explained with reference to FIGS. 9 a and 9 b.
FIG. 2 shows a plan view of the front side 11 of the micro-evaporator plate 10 shown in FIG. 1 , said plate consisting of a highly-conductive material such as steel. An inlet 12 runs upward from the bottom and ends in a liquid feed chamber 13 . The liquid feed chamber 13 expands in the direction of flow and has a curved end area which connects with the likewise curved inlet area 14 of the trapezoidal area 15 in which the micro-evaporator channels 20 are located that are best viewed in FIG. 3 a to 3 c.
The opposite end of the trapezoidal area 15 has an outlet area 16 that connects with the vapor collection chamber 17 which is provided with an outlet 18 . The vapor collection chamber 17 also has a trapezoidal shape, and the vapor collection chamber 17 narrows from the outlet area 16 of the trapezoidal area 15 toward the outlet 18 . The depth of all the microstructures is 30 μm.
FIG. 3 a shows an enlarged section of the inlet area 14 of the trapezoidal area 15 . Numerous straight micro-evaporator channels 20 are separated from each other by a corresponding number of segments 21 . The width of the segments 21 is minimal at the inlet area 14 so that the inlet openings of the micro-evaporator channels 20 lie directly next to each other to quickly intake the liquid in the feed chamber 13 and conduct it into the micro-evaporator channels 20 .
The micro-evaporator channels 20 in this embodiment are fan-shaped so that the distance between the micro-evaporator channels 20 increases toward the vapor collection chamber 17 as a result of the corresponding widening of the segments 21 . This can be seen by comparing FIGS. 3 a and 3 c that show a section of the middle area and outlet area 16 of the trapezoidal area 15 . The cross-section of the micro-evaporator channels 20 remains the same over the entire length. The cross-section dimensions of the micro-evaporator channels 20 are 30 μm×30 μm. In this manner, several hundred evaporator channels (such as 200 ) can be arranged next to each other.
FIG. 4 again schematically illustrates the embodiment shown in FIG. 3 a to 3 c . We can see that the width B of the radiating or fan-shaped micro-evaporator channels 20 remains constant over their entire length in the trapezoidal area 15 , whereas the width of the segments 21 separating the micro-evaporator channels 20 increases from width A 1 to width A 2 that can be a multiple of width B.
FIG. 5 schematically portrays another embodiment where the micro-evaporator channels 20 ′ have a wave-shaped or meandering design. The liquid to be evaporated necessarily follows the curves of the meandering micro-evaporator channels 20 ′ and is alternately pressed against the left and right side of the micro-evaporator channel walls due to the flow to improve the transfer of heat. At the same time, the construction is compact with a greater length of the micro-evaporator channels 20 ′. In this embodiment as well, the meandering micro-evaporator channels 20 ′ are fan-shaped arising from the increased width of the likewise wave-shaped segments 21 ′.
According to the embodiment shown in FIG. 6 , the micro-evaporator channels 20 ″ have channel sections 22 with a smaller diameter, and channel sections 23 with a larger diameter. This embodiment also increases the contact of the liquid to be evaporated with the channel walls due to the flow and thereby improves the transfer of heat. The individual channel sections 22 , 23 of the neighboring micro-evaporative channels 20 ″ are offset in relation to each other to save space. The design of the segments 21 ″ follows this arrangement.
FIG. 7 shows another embodiment in which individual adjacent, offset, column-shaped segments 25 are sequentially arranged. The individual micro-channels are formed by the channel sections 24 where two channel sections are given dashed lines between two column-shaped segments 25 for clarity. We can clearly see that these channel sections 24 are also connected to the neighboring channel sections 24 . The volume within the micro-evaporator channels thereby increases from the inlet area 14 to the outlet area 16 taking into account the expansion of the vapor in the trapezoidal area 15 .
FIG. 8 shows an enlargement of the underside 19 of the micro-evaporator plate 10 . The heating micro-channels 27 are also separated from each other with segments 28 . An antechamber 26 and a post-chamber 29 are provided that are connected with each other by means of heating channels 27 . These chambers 26 , 29 serve to distribute and collect the heating gas that flows through the heating channels 27 . In addition, FIG. 8 also shows the feed line 32 and the discharge line 33 for the heating gas as well as an intermediate plate 7 that is only structured in the area of the feed and discharge of the steam or liquid to be evaporated.
FIGS. 9 a and b show another embodiment of the micro-evaporator with numerous evaporator plates 10 that are separated from each other by non-structured intermediate plates 7 . This modular design allows the micro-evaporator to be constructed to have any desired throughput.
The micro-evaporator 1 is sealed at the top by a cover plate 5 . The base plate 6 is not shown in this figure. The liquid to be evaporated is supplied and discharged by feed and discharge lines 30 and 31 that are perpendicular to the evaporator plates 10 . The heating gas is supplied by the feed line 32 , and the heating gas is discharged by the discharge line 33 . The cross-sections of individual lines 30 to 33 are adapted to the requirements of the utilized media.
In FIG. 9 b , one can see the structuring of the heating channels 27 on the bottom of the evaporator plate 10 .
An evaporation system is portrayed in FIG. 10 that uses a micro-evaporator 1 . The liquid (water in this instance) was held by a pressurized reservoir 40 . The flow of the unevaporated liquid was determined by a thermal mass flow regulator is 41 . After evaporation, secondary heaters 42 (indicated by the bold arrows) prevent the liquid from condensing. The quality of the generated vapor was determined with a Coriolis flowmeter 43 . The amount of evaporated water can be regulated by the preliminary pressure regulator 44 .
REFERENCE NUMBER LIST
1 micro-evaporator
2 heating plate
3 hole
4 heating element
5 cover plate
6 baseplate
7 intermediate plate
8 groove-like recess
10 micro-evaporator plate
11 front
12 inlet
13 liquid feed chamber
14 inlet area
15 trapezoidal area
16 outlet area
17 vapor collection chamber
18 outlet
19 underside
20 , and 20 ′, 20 ″ micro-evaporator channel
21 , 21 ′, 21 ″ segment
22 channel section with a smaller cross-section
23 channel section with a larger cross-section
24 channel section
25 column-shaped segment
26 antechamber
27 heating channel
28 segment
29 post-chamber
30 feed line for liquid
31 discharge line for vapor
32 feed line for heating gas
33 discharge line for heating gas
40 reservoir
41 mass flow controller
42 secondary heater
43 Coriolis flowcontroller
44 upstream pressure regulator
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. | A micro-evaporator is disclosed which is easy to manipulate and can be operated problem-free over a large temperature range. The micro-evaporator has micro-evaporator channels in a trapezoidal region, comprising an inlet region opening in the liquid feed chamber with a small diameter, and an outlet region opening into the vapor collecting chamber with a large diameter. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a device for detecting contact between a material which does not conduct electricity and an electrode of an electric steel-making furnace.
In an electric steel-making furnace, steel is produced by melting scrap metal in contact with electrodes supplied with a high-intensity electric current. During operation of such a furnace, the electrodes are brought into intimate contact with the scrap charge by being moved under the control of an electric position-regulating device, so that the ends of the electrodes are immersed in the charge of scrap which is to be melted. A position-regulating device of the aforementioned kind is known and, for each electrode, produces a motion-control signal which varies inversely with the electric current flowing through the electrode.
Usually, however, the charge is not uniform and the electrode frequently comes in contact with a material in the charge which does not conduct electricity (e.g. lime, stone or wood). Such a material constitutes an electric resistance through which only a very weak current travels. The result is that the electric position regulating device generates a maximum regulating current, and thus the position regulating device operates to exert a continuous pressure on the electrode. Thereupon, the mechanical resistance of the non-conductive material to any motion of the electrode becomes such that the continuous pressure exerted by the regulating device rapidly breaks the electrode, which then has to be replaced. Electrodes are relatively expensive (over $2,250 at present) and in addition whenever an electrode is broken the furnace must be stopped, which automatically results in appreciable loss of production. The effect of such stoppages on production can easily be estimated from the fact that these stoppages normally last an hour or more and it is common for such stoppages to recur several times in a day.
Faulty operation may also be caused by an electrode which is too short or which is becoming too short as a result of wear. In that case, the arc between the electrode and the charge of scrap radiates under the furnace arc with an intensity which rapidly damages the refractory lining.
Owing to the harmful consequences of such incidents, it is desirable to detect them and remedy them without delay. The basic problem is permanently to check that an order from the regulating device is always effectively carried out and that an electrode is never held stationary when it receives an order to move from the regulating device.
OBJECT OF THE INVENTION
To this end, the invention seeks to provide an electronic device adapted to detect when an electrode is held stationary and to raise it if the stoppage is not in response to an order to stop from a position-regulating device.
BRIEF SUMMARY OF THE INVENTION
The device according to the invention comprises first means connected to measure the regulating current and to produce a set-value signal corresponding to an adjustable predetermined threshold value of the regulating current. Second means are coupled to the electrode-holder for detecting whether the electrode is moving and to produce an electric signal having a first state when the electrode moves and a second state when the electrode is at a stop. A comparator device is connected to receive the set-value signal at a first input and to receive the electric signal produced by the second means at a second input, the comparator device being adapted to produce a control signal having two states, namely a first state in response to two simultaneous input signal each having a first predetermined state and a second state in response to two simultaneous input signals having different states, the control signal being applied to a control input of the regulating device so that when the electrode does not move in response to a regulating current in excess of said threshold regulating current the regulating device automatically raises the electrode.
INTRODUCTION TO THE DRAWING
The invention will now be explained in greater detail by way of example with reference to the single accompanying drawing, which is a simplified diagram of the electric circuit of a device in accordance with the invention.
DESCRIPTION OF PREFERRED EMBODIMENT
In the drawing, one of the electrodes of an electric furnace (not shown) is mounted on a holder 1. The motion of the holder 1 is controlled by a known electro-hydraulic regulator 2 which responds to the current produced by an electronic regulating device 3. The regulator 2 has an excitation winding for each electrode. In a known manner, the motion of holder 1 is related to the regulating current produced by device 3.
The object of the device according to the invention is to detect when the value of the regulating current exceeds a preset threshold and to check that holder 1 is in fact moving under the control of the excitation current. In the particular example described, the regulating current normally varies from 0 to + 100 mA or from 0 to - 100 mA and the threshold is set at + 25 mA.
The device according to the invention comprises an electronic assembly for each electrode. The assemblies are all alike and only one is diagrammatically shown in the drawing. As the diagram shows, the assembly is basically made up of three circuits.
A first circuit is adapted to detect whether the holder is moving or at a stop. The holder is coupled to a device, e.g. a well-known tachometric dynamo, which produces a signal in dependence on the speed at which the holder moves. Let "1" be the state of the signal when the holder is moving and "0" be the state of the signal when the holder is at a stop. The motion-measuring signal A is taken via a blocking diode 12 and filtered in filter 13.
A second circuit is adapted to produce a set-value signal based on a measurement of the regulating current. A potentiometer 21 is connected to the terminals of the excitation winding of the regulator 2. A voltage adjusted in proportion to the regulating current through winding 2 appears on the moving contact of potentiometer 21. An electric filter 22 filters the superposed a.c. component. The filtered voltage is applied to the base of a transistor 23 adapted to be conductive at a low voltage corresponding to a regulating current of e.g. 25 mA. As soon as this threshold is reached, transistor 23 becomes conductive and a "0" signal appears on its collector. After a blocking diode 24, an integrating circuit 25 integrates the set-value signal B over a chosen period of e.g. 7 ms, in order not to take account of any signal lasting less than a minimum time and thus eliminate any instability of the system through "hunting".
The signals obtained at the outputs of the aforementioned two first circuits are applied to the third circuit, which basically comprises a comparator 31, e.g. an operational amplifier. The inverting input is connected to receive the set-value signal B and the non-inverting input is connected to receive the motion signal A. During normal operation, when the corresponding electrode is properly in contact with the charge of scrap, the two input signals are at state "1" and the output signal C of amplifier 31 is at state "0". When, on the other hand, the set-value signal B is at state "1" whereas the motion signal is at state "0" (corresponding to the case when the electrode is held stationary in spite of an order to move received from the regulator), the output signal of amplifier 31 is at state "1". After a slight delay, e.g. of the order of 0.5 seconds, produced on the time constant circuit 32, the signal C is applied to the base of a transistor 33 which then becomes conductive and actuates the control relay 34, whereupon a tell-tale lamp 35 is switched on. Relay 34 applies a control signal R to the regulating device 3 in order to raise the electrode. Advantageously relay 34 has a check circuit which stores the raising signal until the defect has been substantially eliminated by modifying the furnace charge. | An electronic safety device for the electrodes of an electric steel-making furnace in which the position of the electrodes is controlled by a position-regulating device. The safety device is adapted to detect when an electrode has been brought to a stop and automatically raise the electrode if it has not been stopped in response to an order to stop from the position-regulating device. | 5 |
FIELD OF THE INVENTION
This invention relates to a fluid flow control device. It may be used to control the flow of liquids or gases and may, for example, be used to provide velocity control of high pressure flowing fluids. Devices of this general type are sometimes known as variable fluid restrictor control values, and are exemplified by Self U.S. Pat. Nos. 3,451,404 and 3,514,074 which have frictional passageways, and by Self U.S. Pat. No. 3,513,864 which has multiple abrupt, angular turn passageways.
BACKGROUND OF THE INVENTION
In the handling of flowing high pressure fluids, it has been customary to utilise orifice means having a high velocity short throat section to attain energy losses or high pressure drops. If the fluid is in a liquid state and liable to flash, that is, vaporise or turn to a gaseous condition on the downstream side of the orifice or valve opening, it may condense implosively and induce damaging shock waves, cause erosion, and the like. Also, as the velocity of the fluid in the valve exceeds the velocity of the fluid in the line, several disturbing reactions occur. A most serious problem is rapid erosion of the valve surfaces by direct impingement of the liquid and any foreign particle suspended therein. Additional erosion results from cavitation. Cavitation may be defined as the high speed implosion of vapour against those internal parts of the valve controlling flow (the valve trim) and the valve body.
In addition to the severe problems resulting from erosion, the increased velocity also causes the flow characteristics of the valve to become unpredictable and erratic.
Other problems created by the high fluid velocity in the valve are severe noise generation, trim fatigue and possible degradation of flowing fluid materials such, for example, as polymers.
Fluid-borne noise downstream of control valves is often very high. If not treated or contained with the pipe, this noise can result in sound pressure levels of 110 to 170 dB three feet from the valve exit. Sound sources of this magnitude are hazardous to personnel and frequently result in complaints from local residents.
Mufflers and silencers can typically only attenuate fluid-borne noise 20 to 30 dB. Therefore, only partial success has been achieved with them in obtaining desired sound pressure levels.
Furthermore, a typical path treatment system ie, the muffler, lagging support structure etc is very cumbersome and expensive, often, the total cost of path treatment for noise can exceed the valve cost many times over.
In order to overcome or ameliorate the above problems, there have been introduced devices which effect energy losses in high pressure fluids without increasing velocity and shock wave reaction by sub-dividing the flow into a plurality of small, long passageways with abrupt turns creating friction and pressure drop in the fluid, thus avoiding damage and erosion in the equipment. Such a device is disclosed, for example, in U.S. Pat. No. Re. 32,197. There, the passageways are provided in an annular stack of separate members having abutting faces enclosing a plurality of individual passageway grooves which are angular between the inlet and outlet of the stack to turn the fluid and to provide a substantially longer flow length than between the inlet and outlet ends of the stack. The stack is mounted in the fluid passage of a valve housing and a valve plug movable within the annular structure controls the number of passageways in the stack through which the fluid can flow.
A modified device of this type is disclosed in GB-A-2,273,579 in which at least one passageway in the stack of members of discs includes a void between the inlet and outlet region of the disc, the void expanding the cross-sectional area of the energy loss passageway.
Valves incorporating a flow control device including a stack of discs having energy-loss passageways have become very successful commercially and it is an object of the present invention to provide an improvement in devices of this type.
SUMMARY OF THE INVENTION
According to the invention a fluid flow control device comprises a plurality of pairs of annular discs forming a rigid structure which incorporates a series of substantially radial passageways for fluid flow,
each disc of said pair having passageways therein which extend only partially through said disc in a radial direction,
the pair of discs being aligned with one another such that the passageways in one disc interconnect with the passageways in the other disc of the pair so as to provide for fluid flow through the pair of discs.
The invention further provides a fluid flow control device comprising a plurality of discs forming a rigid structure which incorporates a series of passageways for fluid flow, the discs having abutting surfaces and passageways therebetween for fluid flow, inlet means formed in said discs to define a predetermined inlet area for conducting fluid to the series of passageways formed by said rigid structure, outlet means associated with said inlet means to provide a series of openings for exhausting fluid from the passageways, and wherein at least one of the passageways is of smaller cross-section in a mid-region of its respective discs and increases in cross-section from said mid-region towards the inlet and towards the outlet region of said discs.
The invention also provides a pair of discs for incorporation in a structure as defined in the immediately preceding paragraph, each disc containing a radially-extending series of holes through its thickness, and the series of holes being different in the two discs, so that the discs may be superimposed with their holes overlapping, the overlapped holes providing radial flow passageways through the superimposed pair of discs, wherein the passageways are of smaller cross-section in a mid-region of the discs and increasing in cross section from said mid-region towards the centre and towards the outer peripheries of the discs.
The discs may be annular and the passageways increase in cross-section from the mid-region of the annuli towards their inner and outer peripheries.
The discs of the superimposed pair may be identical so that each disc comprises at least two different radially-extending series of holes and the discs are rotated relative to each other so that a first series of holes of one disc is superimposed on a second series of holes of the other disc and vice versa.
Each adjacent pair of discs in a stack of discs may be provided with a flow passageway having the smaller cross-section in the mid-region or, if desired, the invention may be applied to a proportion only of the discs in the structure.
The discs are preferably annular so that the rigid structure or stack formed from the discs contains a central passageway in which a reciprocating valve plug may move to increase or decrease, as desired, the number of flow passages open through the stack. The inlets to the passageways may be at the inner circumference of the discs with the outlets at the outer circumference or, alternatively, the outlets may be at the inner circumference and the inlets at the outer circumference.
The invention in this aspect provides a bidirectional flow path through the device. It is particularly useful, therefore, for the regulation of fluid flow both in and out of, for example, a storage system, e.g. an underground gas storage system. A valve incorporating a flow device according to this aspect of the invention may, therefore, advantageously replace two valves conventionally used, i.e. one for injection and one for withdrawal of the fluid, e.g. natural gas into and from an underground storage.
In another aspect the invention provides a fluid flow control device comprising a plurality of discs forming a rigid structure which incorporates a series of passageways for fluid flow, the discs having abutting surfaces and passageways therebetween for fluid flow,
and wherein each disc has at least one first passageway formed through the entire thickness of the disc and extending from the outer edge of the disc to end in a mid-region of the disc and at least one second passageway formed through the entire thickness of the disc and extending from the inner edge of the disc to end in a mid-region of the disc, adjacent pairs of discs being orientated so that each first passageway of one disc communicates with a second passageway of the other disc and each second passageway of said one disc communicates with a first passageway of said other disc.
The invention also provides a disc suitable for incorporation in a structure according to the immediately preceding paragraph, the disc having at least one first passageway formed through the entire thickness of the disc and extending from the outer edge of the disc to end in a mid-region of the disc and at least one second passageway formed through the entire thickness of the disc and extending from the inner edge of the disc to end in a mid-region of the disc.
By appropriate orientation of each pair of discs in the stack, each pair of discs may provide one or more passageways isolated from the passageways provided by other pairs of discs in the stack.
The passageways so defined may be designed to have abrupt turns to create drag and pressure drop in a fluid. They may be of smaller cross-section in the mid-region of the disc--as defined in the first aspect of the present invention. Alternatively or additionally, they may increase in section so as to provide an expanding volume from inlet to outlet so as to provide a desired reduction in energy of fluid flowing through the passageways. In another embodiment the passageways may define a void between the inlet and outlet to expand the cross-sectional area of the passageway as disclosed in GB-A-2,273,579.
The discs defined by the second aspect of the invention are particularly advantageous in that the passageways are easier to machine. Thus they may be wire EDM-or water jet-machined through the thickness of the disc and discs of carbide or ceramic material may be machined without the need for special tooling.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:
FIG. 1 is a longitudinal cross-section of a valve utilising a flow control device of the present invention;
FIG. 2a) is a plan view of a portion of one form of disc according to one aspect of the invention for use, for example, in the flow control device of FIG. 1;
FIG. 2b) is a plan view of a portion of a pair of discs of the type shown in FIG. 2a) superimposed one upon the other;
FIGS. 2c) and 2d) are identical sections along line A--A of FIG. 2b) with the addition of separator plates but showing flow in opposite directions;
FIG. 3a) is a plan view of a disc according to a second aspect of the invention;
FIG. 3b) is a similar view of another disc as shown in FIG. 3a) but rotated through 45°;
FIG. 3c) shows the two discs of FIGS. 3a) and 3b) superimposed one upon the other;
FIG. 3d) shows four discs of the type shown in FIGS. 3a) and 3b) superimposed on each other;
FIG. 4a) is a plan view of another disc according to the second aspect of the invention;
FIG. 4b) is a similar view of another disc as shown in FIG. 4a) but rotated through 221/2°;
FIG. 4c) shows the two discs of FIGS. 4a) and 4b) superimposed one upon the other; and
FIG. 4d) is a plan view of a separator plate to be used as described below in conjunction with the two stacked discs of FIG. 4c).
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 discloses a fluid exhaust valve assembly 10 for exhausting, e.g. a predetermined amount of steam, to the atmosphere 12 through an inlet 16. The fluid flows into a chamber 18 from which a predetermined amount of the fluid is allowed to exhaust through the stack assembly 14 by a movable valve plug 20. The valve plug 20 is movable between a first position completely blocking the fluid from entering the stack assembly 14 by completely blocking all the inlets 22 of the stack assembly 14 and a second position opening all the inlets 22 by moving up into a space 24 formed by a top casing 26 of the valve assembly 10. The plug 20 is moved by a connecting rod 28 connected to an actuator (not shown) which is responsive to system control signals in a well-known manner. To minimise the force that the actuator has to exert to move the plug 20 between positions, fluid pressure is balanced across the plug 20 by providing a pair of passageways 30 extending longitudinally across the plug 20 for fluid communication between the chamber and the space 24.
The disc stack assembly 14 includes a series of individual discs 32 which are aligned with respect to the plug 20 and are clamped together by tension rods 34 between a bottom mounting plate 36 to encompass the stack assembly 14 and safely direct the fluid exiting from outlets 42 of the stack assembly up into the atmosphere. The disc stack assembly provides a labyrinth for the fluid as it travels from the inlets 22 to the outlets 42 by means of variously configured discs 32 as it will be described below.
In FIG. 2a) an annular disc 32A has two repeating series of radially-extending, generally rectangular holes through it. Series 33 comprises a slot 33A at the outer periphery 34, an intermediate hole 33B of smaller transverse dimensions than slot 33A and a slot 33C at the inner periphery 35 of the disc. Slot 33C is of similar dimensions to slot 33A. The second series of holes is positioned radially at 45° to the first series. The second series comprises two holes 36A and 36B, again of generally rectangular form. Holes 36A and 36B are intermediate in transverse dimensions between slots 33A and 33C on the one hand and hole 33B on the other hand. They are also radially centred to lie between the radial centres of the holes of the first series. The two series (only one of each being shown) alternate at 45° intervals around the disc.
FIG. 2b) shows two discs according to FIG. 2a), one of which has been rotated at 45° with respect to the other and the two discs are superimposed so that a hole 36A of the top disc partially overlies a slot 33A and a hole 33B of the bottom disc to form passageways 37A and 37B and a hole 36B of the top disc partially overlies hole 33B and a slot 33C of the bottom disc to form passageways 37C and 37D.
A similar overlap takes place at each 45° interval but with alternate series of passageways being formed with the holes 36A and 36B being in the lower disc.
It will be seen the passageway 37A towards the periphery of the discs is of greater cross-section than passageways 37B and 37C in the mid-region of the discs and that passageway 37D towards the inner periphery of the discs is again of greater cross-section than passageways 37B and 37C.
FIGS. 2c) and 2d) both show in section a stack of two discs 32A superimposed as shown in FIG. 2b) and with separator discs 38 and 39 to close off and define the top and bottom respectively of the passageways. As shown by arrows the flow may be from the inner periphery to the outer periphery--FIG. 2c) or from the outer periphery to the inner periphery--FIG. 2d).
In FIG. 3a), disc 32B is shown having four equi-spaced passageways 62, each cut through the entire thickness of the disc and extending from the outer edge 64 of the disc to end in a central region 66 of the disc. The disc also has four equi-spaced passageways 68, each also cut through the entire thickness of the disc and extending from the inner edge 70 to the mid-region 66 of the disc. Each passageway 62 is positioned midway between an adjacent pair of passageways 68 and vice versa.
In FIG. 3b) a similar disc 32B' is shown rotated through 45° with respect to disc 32B. Disc 32B' has the same arrangement of passageways 62' and 68' as has disc 32B and like parts are indicated by the same but prime numbers.
A pair of discs 32B and 32B' are abutted face to face with one of the discs rotated through 45° with respect to the other and this is shown in FIG. 3c). The mid-region end of each passageway 62 on disc 32B overlaps with the mid-region end of a passageway 68' on the other disc 32B' and similarly with passageways 62' and 68 thereby creating eight flow passageways between the outer edges 64, 64' and inner edges 70, 70' of the pair of discs.
As shown, each passageway 62, 68' or 62', 68 is provided with a number of right angle turns 69 to provide friction and energy loss for a fluid passing through the passageway.
In FIG. 3d) is shown in plan a stack 71 of two pairs of discs, the discs of each pair being superimposed on each other in the manner shown in FIG. 3c) but each pair being rotated at 221/2° with respect to the other pair. By this means passageways 72 and 72' in the upper pair are defined in between passageways 62 and 62' of the lower pair. It will be appreciated that each passageway from the outer to inner edges of the discs is isolated from adjacent passageways of that pair by the intervening areas of the discs and each passageway in one pair of discs is isolated from each passageway in an adjacent pair of discs by the abutting faces of adjacent discs.
In FIG. 4a) a disc 32C has eight equi-spaced passageways 82, each cut through the entire thickness of the disc and extending from the outer edge 84 of the disc to end in a mid-region 86. The disc also has eight equi-spaced passageways 88 cut through the entire thickness of the disc and extending from the inner edge 90 to the mid-region 86 of the disc. Each passageway 82 is positioned midway between an adjacent pair of passageways 88 and vice versa.
In FIG. 4b) a similar disc 32C' is shown rotated through 221/2° with respect to the disc 32C. Disc 32C' has the same arrangement of passageways 82' and 88' as has disc 32C and like parts are indicated by the same but prime numbers.
A pair of discs 32C and 32C' are abutted face to face with one of the discs rotated through 221/2° with respect to the other and this is shown in FIG. 4c). The mid-region end of each passageway 82 on disc 32C overlaps with the mid-region end of a passageway 88' on the other disc and similarly with passageways 82' and 88 thereby creating sixteen flow passageways between the outer edges 84, 84' and 90, 90' of the pair of discs.
As shown each passageway 82, 88' or 82', 88 is provided with a number of right angle turns 89 as before.
FIG. 4d) shows a plan view of an annular separator disc 100. One disc 100 can be located between each pair of superimposed discs 32C and 32C' in a stack of such pairs in order to maintain the flow passageways within their respective pairs of discs.
It will be appreciated that the invention is not limited to the embodiments shown. For example, in the FIGS. 3 and 4 embodiments, there may be more or less passageways as desired. The passageways may contain voids as described above.
The valve arrangement of FIG. 1 may be changed so that the fluid travels in the reverse direction, i.e. fluid inlets at 42 and outlets at 22 and 16.
The device may be utilised in a valve arrangement to control flow into and out of a fluid storage system. | A fluid flow control device for use in a variable fluid restrictor control valve or severe service control valve. These valves employ a moveable plug and are used to control high pressure fluids e.g. superheated steam. The control device of the invention includes annular discs with fluid passageways through them. Pairs of discs together form a radial passageway for fluid between the interior of a stack of discs and its radially outer circumference. The passageways may have a smaller cross-section at a mid-region of the disc than at the radially inner or outer side of the disc. | 5 |
[0001] This application is a divisional application of co-pending U.S. patent application Ser. No. 10/556,573, entitled SPREAD SPECTRUM MODULATOR AND DEMODULATOR, which is a Nov. 14, 2005 national stage entry of PCT Patent Application No. PCT/FR04/01096, filed May 6, 2004, which claims the benefit of French Patent Application Serial No. 0305796, filed on May 14, 2003, the disclosures of which are fully incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to transmission diversity techniques used in the field of spread spectrum radio communications. It applies in particular to radio communications with code division multiple access (CDMA).
[0003] A transmission channel between a transmitter provided with n transmission antennas and a receiver provided with m reception antennas is considered. A spreading code c(t), consisting of a periodic sequence of complex samples called “chips” of rate f c , is allocated to this channel. It serves to modulate n sequences of complex symbols s i (t) (1≦I≦n) having a symbol rate f s that is smaller than f c . The ratio SF=f c /f s is the channel spreading factor. The signal y j (t) picked up by the j-th reception antenna (1≦j≦m) may be written:
[0000]
y
j
(
t
)
∑
i
=
1
n
s
i
(
t
)
[
c
(
t
)
⊗
h
ij
(
t
)
]
+
w
(
t
)
(
1
)
[0000] where {circle around (×)}designates the convolution operation, and w(t) designates the white noise and Gaussian noise. For one and the same user, the same spreading code is used on the various transmission antennas. In a CDMA system, the noise w(t) contains contributions pertaining to other users of the system.
[0004] The impulse response h ij (t) of the propagation channel between the i-th transmission antenna and the j-th reception antenna is conventionally estimated by the receiver by virtue of known pilot sequences transmitted respectively by the n transmission antennas. It is generally modeled as a set of p paths taking into account per pair of antennas (p≧1), the k-th path (1≦k≦p) corresponding to a reception delay τ k and to a complex reception amplitude a ijk . Each propagation channel (i-th transmission antenna to j-th reception antenna) is thus associated by the receiver with a vector of p amplitudes: A ij =[a ij1 , a ij2 . . . a ijp ] T , (the notation [.]T designates transposition).
[0005] The demodulation in a spread spectrum system consists in despreading the signal received at the level of each echo, by correlating the signal received with the spreading code. The receiver most commonly used is the “rake” receiver, in which the signal emanating from each antenna j is subjected to a filter matched to the spreading code whose output is sampled at the instants corresponding to the p paths identified. This provides a vector Z=[z 11 . . . z 1p z m1 . . . z mp ] T , where Z jk designates the output of the matched filter relating to antenna j, sampled with the delay τ k . Thus, at a given symbol time, the following system of equations is obtained:
[0000] Z=HS+N (2)
[0000] where
[0000]
H
=
[
A
11
…
A
n
1
⋮
⋱
⋮
A
1
m
…
A
nm
]
[0000] is a matrix representative of the overall channel, of mp rows and n columns;
S=[s 1 . . . s n ] T is a vector containing the n symbols transmitted at the time considered from the n transmission antennas; and
N is a noise vector of size mp.
[0006] The system (2) is of a form very commonly encountered in signal processing. It is easily solved by a conventional least squares estimation procedure (MMSE, “minimum mean squared error”) on condition that the rank of the matrix H is at least equal to n. The MMSE solution may be written: Ŝ
[0000] Ŝ= ( H*H ) −1 H*Z (3)
[0007] Assuming that the antennas are not perfectly correlated, the rank of the matrix H is generally equal to the minimum of the integers n and mp. The necessary and sufficient condition to be able to solve the system (2) by the MMSE procedure is then mp≧n. Once this condition is satisfied, it is possible to solve the system according to the desired technique, by the MMSE procedure or by another procedure such as for example maximum likelihood sequence estimation (MLSE, this MLSE procedure may also be applied when mp<n, but it is then very unstable and sensitive to noise).
[0008] The performance of the receiver depends on the conditioning of the matrix of the channel H, which depends on the number m of reception antennas, the number p of paths and the decorrelation properties of the antennas. Correlated antennas cause poor conditioning due to the fact that the matrix H*H then has eigenvalues close to zero which disturb its inversion in the solution according to (3). In general, the designer of a radio station with multiple antennas contrives matters such that they are decorrelated, by spacing them sufficiently far apart and/or by making them radiate according to different polarities.
[0009] In the known systems with multiple inputs and multiple outputs (MIMO), i.e. with n≧2 and m≧2, one seeks to increase the accessible communication throughput for a given transmitted power, by transmitting different symbols s 1 , . . . , s n through the n transmission antennas. These symbols may be mutually correlated, if they emanate from a space-time coding, or independent. To definitely comply with the condition on the rank of the matrix H, the receiver should be equipped with at least n reception antennas. Otherwise the system (2) would be insoluble in the presence of a single path.
[0010] Examples of such MIMO systems are described in European Patent Application Publication Nos. EP 0 817 401, EP 0 951 091, and EP 1 117 197 and PCT Patent Application Publication Nos. WO 99/14871 and WO 99/45657.
SUMMARY OF THE INVENTION
[0011] An object of the present invention is to improve the performance of the transmission chain in a transmission diversity scheme with n antennas.
[0012] The invention thus proposes a spread spectrum modulator for converting n input sequences composed of digital symbols into n spread spectrum sequences in a radio transmitter, n being a number at least equal to 2. This modulator comprises a spreading code generator and means of combining the spreading code with the n input sequences so as to produce the n spread spectrum sequences for transmission from n respective antennas of the radio transmitter. According to the invention, the combining means are arranged so that each spread spectrum sequence corresponds to a sum of at least two contributions mutually shifted by a time substantially less than the duration of a symbol, each contribution being the product of a version of one of the n input sequences times the spreading code.
[0013] The above discussion shows a certain duality between the number m of reception antennas and the number p of paths. The number m generally being limited for hardware cost or bulkiness reasons (in particular in a mobile terminal), the modulator proposed has the advantage of raising the rank of the matrix H by virtue of an increase in the number of paths taken into account in the system (2). This increase results from the artificial creation of one or more additional echoes corresponding to the contributions shifted by a predefined time.
[0014] These contributions will typically have mutual shifts corresponding to the duration of one or more chips of the spreading code. A shift of a chip duration is preferred since it minimizes the lengthening of the impulse response and, in a CDMA system, the degradation of the orthogonality of the codes employed.
[0015] In an embodiment of the modulator, the increase in the number of paths is affected by filtering the transmission signal of each antenna through a filter containing at least two echoes. In order for the rank of the matrix of the overall channel to be increased, these filters must differ from one antenna to another. In particular, in a case where n=2, one of the two spread spectrum sequences corresponds to a sum of two mutually shifted identical contributions, equal to the product of one of the two input sequences times the spreading code, while the other of the two spread spectrum sequences corresponds to a sum of two mutually shifted opposite contributions, one of these two opposite contributions being equal to the product of the other of the two input sequences times the spreading code. The expression for the first filter is then
[0000]
g
1
(
t
)
=
1
+
δ
(
t
-
T
C
)
2
,
[0000] where δ designates the Dirac function and T c is the chip time, while the expression for the second filter is
[0000]
g
2
(
t
)
=
1
+
δ
(
t
-
T
C
)
2
.
[0016] In a preferred embodiment of the modulator, the contributions summed with time shift to form each spread spectrum sequence are respectively obtained on the basis of distinct input sequences. Under these conditions, a symbol transmitted which benefits from one or more existing paths from a given transmission antenna also contributes to the signal transmitted from another transmission antenna. Therefore, the symbol benefits from one or more other paths. This transmission diversity of the symbol decreases its sensitivity to channel fadeouts, so that it can be detected under better conditions by the receiver.
[0017] The gain obtained may be of the order of 3 dB.
[0018] In particular, in a case where n=2 and the symbols are complex, one of the two spread spectrum sequences corresponds to a sum of a first and of a second mutually shifted contributions. While the other of the two spread spectrum sequences corresponds to a sum of a third and of a fourth mutually shifted contributions, the first contribution is the product of a first of the two input sequences times the spreading code. The second contribution is the opposite of the product of the complex conjugate of the second input sequence times the spreading code. The third contribution is the product of the second input sequence times the spreading code. The fourth contribution is the product of the complex conjugate of the first input sequence times the spreading code.
[0019] A transmission diversity of the same kind is produced in known space and time diversity schemes (STTD, “space time transmit diversity”). However, the shift between the contributions respectively transmitted by the antennas and originating from one and the same symbol in the conventional STTD scheme are shifted by a symbol time, so that this scheme does not produce additional echoes in the impulse response and affords no gain in throughput. An STTD scheme is in particular standardized within the framework of UMTS networks (“universal mobile telecommunication system”). See Section 5.3.1 of technical specification TS 25.211, “Physical channels and mapping of transport channels onto physical channels (FDD) (Release 1999)”, version 3.3.0, published in June 2000 by the 3GPP (3rd Generation Partnership Project).
[0020] In another embodiment, the contributions summed to form the n spread spectrum sequences are all obtained on the basis of distinct input sequences. The modulator then utilizes the presence of the additional echo or echoes to multiply the transmission throughput over the channel.
[0021] The mutually shifted contributions are advantageously summed with a uniform distribution of power.
[0022] Provision may also be made to sum them with a power distribution determined as a function of information on a number of stations to which spreading codes have been allocated so as to receive signals originating from the radio transmitter. The distribution will generally be less uniform when many users have codes allocated, since this better preserves the orthogonality of the codes allocated to the various users.
[0023] Another aspect of the present invention pertains to a radio transmitter, comprising n transmission antennas, means of obtaining input sequences composed of digital symbols, a spread spectrum modulator as defined above for converting input sequences into n spread spectrum sequences, circuits for producing n respective radio frequency signals on the basis of the n spread spectrum sequences and means for providing respectively the n radio frequency signals to the n transmission antennas.
[0024] The invention also proposes a demodulator suitable for the reception of signals originating from such a transmitter. This demodulator serves to convert m spread spectrum sequences respectively arising from m reception antennas of a radio receiver into at least n sequences of estimations of digital symbols transmitted at a symbol rate by the transmitter, m being a number at least equal to 1, n being a number at least equal to 2 representing a number of transmission antennas of the transmitter. It comprises means for detecting propagation paths between the transmission and reception antennas, means of despreading of each of the m spread spectrum sequences with a predefined spreading code so as to produce echo components at the symbol rate, and means of combining the echo components to produce the n symbols estimation sequences. According to the invention, the echo components taken into account comprise at least two echo components for a detected path, representing associated echoes having a mutual shift by a time substantially less than the duration of a symbol.
[0025] Another aspect of the present invention pertains to a radio receiver, comprising m reception antennas, means of obtaining m respective spread spectrum sequences on the basis of the m reception antennas, and a demodulator as defined hereinabove for converting the m spread spectrum sequences into at least n sequences of estimations of digital symbols transmitted by the transmitter.
DESCRIPTION OF THE DRAWINGS
[0026] Other features and advantages of the present invention will become apparent in the description hereinbelow of non-limiting exemplary embodiments, with reference to the appended drawings, in which:
[0027] FIG. 1 is a schematic diagram of an embodiment of a radio transmitter according to the invention;
[0028] FIGS. 2 and 3 are schematic diagrams of two embodiments of a radio receiver according to the invention;
[0029] FIGS. 4 to 6 are schematic diagrams of variant embodiments of the radio transmitter according to the invention.
DETAILED DESCRIPTION
[0030] Interest is focused on the transmission of sequences of digital symbols s i through a spread spectrum technique. This transmission may in particular take place in a cellular radio communication system of UMTS type which uses the CDMA technique.
[0031] We consider a transmitter with n antennas and a receiver with m antennas, with n≧2 and m≧1. Often, the transmitter will form part of a base station of the cellular system with typically n=2, while the receiver will form part of a mobile terminal with typically m=1. A fixed base station is in fact better suited to the installation of multiple antennas, spaced apart mutually so as to be well decorrelated. It will nevertheless be noted that the terminal could comprise multiple antennas, for example collocated antennas with cross polarizations. Moreover, the transmitter described hereinbelow could be in the terminal and the receiver in the base station.
[0032] The radio transmitter represented in FIG. 1 comprises n=2 decorrelated transmission antennas 18 . It transmits over a communication channel a binary sequence x destined for a receiver. A spreading code c(t) is allocated to this communication channel. The chip rate f c =1/T c of the spreading code is 3.84 Mchip/s in the case of UMTS, the spreading factor being a power of 2 lying between 4 and 512.
[0033] The radio modulation employed is a quaternary phase shift keying (QPSK) which admits complex symbols whose real and imaginary parts modulate two quadrature carriers. A multiplexer 10 distributes the bits x of the sequence to be transmitted over the real and imaginary parts of the symbols s 1 , s 2 destined for the transmission pathways on the two antennas 18 . There are thus two symbols s 1 , s 2 transmitted at each symbol time T s =1/f s , i.e. four bits.
[0034] To artificially duplicate the echoes which will be picked up at the receiver, a delayed version of each symbol s 1 , s 2 is generated, as shown diagrammatically in FIG. 1 by the element 11 which introduces a delay of a chip time T c . The delayed version of the symbol s 1 is added to its non-delayed version by the adder 12 , thus effecting the filter g 1 (t) mentioned previously to within a factor √{square root over (2)}. The delayed version of the symbol s 2 is deducted from its non-delayed version by the subtractor 13 , thus effecting the filter g 2 (t) mentioned previously to within a factor √{square root over (2)}.
[0035] The output samples from the adder 12 and from the subtractor 13 are multiplied at 14 by the spreading code c(t) of the channel delivered by a pseudorandom generator 15 . The n=2 spread spectrum signals which result therefrom are multiplied by the number P/√{square root over (2)}, as symbolized by the amplifiers 16 , P being a transmission power adjustment factor specified for the pair of symbols s 1 , s 2 and which is for example determined in a conventional manner by closed-loop feedback control.
[0036] The spread spectrum signals thus produced by the modulator are addressed to the radio stage 17 which executes the conventional operations of conversion to analog, filtering, QPSK modulation, power amplification, etc., serving to produce the radio signals feeding the antennas 18 .
[0037] FIG. 2 shows a radio receiver with m=1 reception antenna 20 , capable of communicating with a transmitter according to FIG. 1 .
[0038] The radio stage 21 executes the conventional operations of amplification and of filtering of the radio signal picked up by the antenna 20 , transposes it to baseband or to intermediate band and digitizes it so as to provide the spread spectrum signal R 1 processed by the demodulator.
[0039] The latter comprises a probing module 22 which calculates the correlations of the signal R 1 with beacon signals allocated respectively to the transmission antennas. In the case of downlinks (from a base station to a terminal) each antenna of the base station has a pilot channel termed CPICH (“Common Pilot Channel”), with spreading factor 256, over which is transmitted a beacon signal described in section 5.3.1 of technical specification 3 G TS 25.211, version 3.3.0, “Physical Channels and Mapping of Transport Channels onto Physical Channels (FDD)—Release 1999” published in June 2000 by 3GPP.
[0040] The probing module 22 allows the receiver to estimate the p delays associated with p propagation paths for each antenna of the transmitter and the n corresponding vectors A i1 (1≦i≦n). In practice, the delays are the same for the various transmission antennas, since a distance of the order of a meter between the antennas, sufficient to ensure decorrelation, represents a negligible time shift, of the order of a hundredth of the duration of a chip.
[0041] The p estimated delays are provided to a matched filter 23 which receives the spread spectrum signal R 1 and despreads it by convolving it with the complex conjugate c*(t) of the spreading code of the communication channel, delivered by the pseudorandom generator 24 . The output of the matched filter 23 is sampled at the instants corresponding to the p estimated delays, thereby providing the mp=p first components of the vector Z (case m=1). According to the invention, the output of the matched filter 23 is moreover sampled at the instants corresponding to the p estimated delays plus a chip time, thereby providing mp=p additional components of the vector Z.
[0042] A module 25 combines the components of the vector Z, taking account of weighting coefficients deduced from the vectors A i1 estimated by the probing module 22 . The combination restores the estimates ŝ 1 , ŝ 2 of the transmitted symbols s 1 , s 2 , which the demultiplexer 26 sorts so as to construct the estimated binary sequence {circumflex over (x)}.
[0043] The combination module 25 may in particular determine
[0000]
S
^
=
[
s
^
1
s
^
2
]
[0000] according to the conventional MMSE procedure:
[0000] Ŝ= (Φ*Φ) −1 Φ*Z (4)
[0000] given that, owing to the additional echoes introduced artificially (positioned at the end of the vector Z), the system to be solved has become:
[0000] Z=ΦS+N (5)
[0044] When the transmitter is in accordance with FIG. 1 , the matrix Φ of expressions (4) and (5) is given by:
[0000]
Φ
=
1
2
[
A
11
A
21
A
11
-
A
21
]
(
6
)
[0045] In the case of FIG. 2 , where m=1, when a single propagation path is identified by the module 22 (p=1, A 11 =[a 111 ], A 21 =[a 211 ]), we see that the conventional system (2) is insoluble since the number of rows, and hence the rank, of the matrix H=[a 111 , a 211 ] is smaller than the number n of antennas of the transmitter. However, on account of having introduced the additional artificial echoes to the transmitter it becomes possible to surmount this problem by carrying out the estimations according to (4).
[0046] If two propagation paths are identified by the module 22
[0000]
(
p
=
2
,
A
11
=
[
a
111
a
112
]
,
A
21
=
[
a
211
a
212
]
)
,
[0000] system (2) will generally be soluble since the rank of the matrix
[0000]
H
=
[
a
111
a
211
a
112
a
212
]
[0000] is generally mp=2=n. On account of having introduced the additional artificial echoes to the transmitter it becomes possible here to improve, in the presence of fading, the conditioning of the matrix Φ used in the combination according to (4).
[0047] The radio receiver illustrated by FIG. 3 possesses m=2 decorrelated reception antennas 20 , thereby ensuring that the system (2) is always soluble. Here again, the artificial increase in the number of paths generally improves the conditioning of the matrix of the channel.
[0048] Each antenna 20 is associated with a reception chain 21 - 23 identical to that described with reference to FIG. 3 . The combination module 28 determines the two symbols estimated as ŝ 1 , ŝ 2 according to (4), with:
[0000]
Φ
=
1
2
[
A
11
A
21
A
12
A
22
A
11
-
A
21
A
12
-
A
22
]
(
7
)
[0049] FIGS. 4 and 5 show preferred variants of the transmitter of FIG. 1 , in which the processing applied to introduce additional echoes is not a simple filtering of the symbols destined for the transmission antennas. In the artificially created echo, the symbols s 1 , s 2 pertaining to the two antennas are permuted, so that the spatial diversity is harnessed.
[0050] In the case of FIG. 4 , after having respectively transmitted α.s 1 and α.s 2 on the n=2 antennas, we retransmit β.s 2 and β.s 1 , for example T c later, so that we carry out a permutation of symbols and a weighting of the echoes by coefficients α and β such that |α| 2 +|β| 2 =1. The weighting by the coefficient α is applied to the symbols by the multipliers 30 , and the weighting by the coefficient β is applied to the delayed symbols by the multipliers 31 . Two adders 32 respectively sum the two contributions for the two transmission antennas.
[0051] The matrix Φ used by the combination module of the receiver according to relation (4) then becomes:
[0000]
Φ
=
[
α
A
11
α
A
21
β
A
21
β
A
11
]
(
8
)
[0000] in the case of a receiver with m=1 antenna ( FIG. 2 ), and:
[0000]
Φ
=
[
α
A
11
α
A
21
α
A
12
α
A
22
β
A
21
β
A
11
β
A
22
β
A
12
]
(
9
)
[0000] in the case of a receiver with m=2 antennas ( FIG. 3 ).
[0052] The weighting may be uniform, as in the case of FIG. 1 , i.e.
[0000]
α
=
β
=
1
2
.
[0000] It may also vary as a function of the number of codes allocated in CDMA. The duplication of the echoes causes the strict orthogonality of the codes employed to be lost, so that it is advantageous to unbalance the weighting (α tends to 1 and β to 0) when the number of codes allocated to users increases.
[0053] In order to facilitate the demodulation at the receiver level, the permutation of the symbols may involve an operation of complex conjugation of the symbols. This is what is carried out in the modulator of FIG. 5 , which retransmits
[0000]
-
s
.
2
2
and
s
.
1
2
[0000] as artificial echoes (uniform weighting). The complex conjugates of the delayed symbols are obtained by respective modules 40 . A subtractor 41 calculates the difference s 1 (t)−s 2 *(t−T c ), while an adder 42 calculates the sum s 2 (t)+s 1 *(t−T c ). The remainder of the modulator is similar to that of FIG. 1 .
[0054] The matrix Φ used by the combination module of the receiver according to relation (4) then becomes:
[0000]
Φ
=
1
2
[
A
11
A
21
A
.
21
-
A
.
11
]
(
10
)
[0000] in the case of a receiver with m=1 antenna ( FIG. 2 ), and:
[0000]
Φ
=
1
2
[
A
11
A
21
A
12
A
22
A
.
21
-
A
.
11
A
.
22
-
A
.
12
]
(
11
)
[0000] in the case of a receiver with m=2 antennas ( FIG. 3 ).
[0055] We then obtain the important advantage that the matrix Φ of the channel is orthogonal:
[0000] (Φ*Φ)=(Σ i,j A ij A ij ) l n (12)
[0000] where l n designates the identity matrix of size n.times.n. Under these conditions, the MMSE and MLSE procedures are equivalent
[0000]
(
S
^
=
1
∑
i
,
j
A
i
,
j
A
i
,
j
φ
*
Z
,
[0000] and the required calculation complexity is reduced.
[0056] It is also possible to transmit other symbols on the various replicas so as to increase the throughput by virtue of the multiplication of the paths. In this case, the contributions summed to form the n spread spectrum sequences are all obtained on the basis of distinct input sequences. For example, we transmit respectively
[0000]
s
1
2
and
s
2
2
[0000] on the n=2 antennas, then
[0000]
s
3
2
and
s
4
2
[0000] and so on. There are then 2n sequences of symbols s 1 , s 2 , s 3 , s 4 input to the modulator.
[0057] This is what is illustrated in FIG. 6 , where the input multiplexer 50 produces 2n=4 sequences of quaternary symbols. Four symbols s 1 , s 2 , s 3 , s 4 are thus transmitted in a symbol time by means of n=2 antennas. The symbols s 3 and s 4 are delayed by a chip time by the element 51 . A first adder 52 calculates the sum s 1 (t)+s 3 (t−T c ), while a second adder 53 calculates the sum s 2 (t)+s 4 (t−T c ). The remainder of the modulator is similar to that of FIG. 1 .
[0058] The corresponding demodulator, whose number of antennas m must then be at least equal to n, detects the p real paths with the aid of the pilot channel, and assigns these p paths to the symbols s 1 and s 2 and the same p paths shifted by a chip time to the symbols s 3 and s 4 .
[0059] The matrix Φ used by the combination module of the receiver with m=2 antennas to estimate
[0000]
S
^
=
[
s
^
1
s
^
2
s
^
3
s
^
4
]
[0000] according to relation (4) then becomes:
[0000]
Φ
=
1
2
[
A
11
A
21
0
0
A
12
A
22
0
0
0
0
A
11
A
21
0
0
A
12
A
22
]
(
13
)
[0060] The monitoring of the modulation and demodulation process may advantageously take account of the information on the richness of the channel in terms of multipaths, i.e. on the number p, so as to decide whether or not the artificial generation of additional paths is to be applied.
[0061] Such information may for example be provided by the mobile terminal and/or by the base station in the manner described in PCT Patent Application Publication No. WO 03/005753. It may also be summarized through measurements of variance as described in French Patent Application No. 02 04251, filed Apr. 5, 2002 (see French Patent Application Publication No. 2828279, published Sep. 24, 2004).
[0062] By way of example, the modulator and the demodulator may be controlled jointly so that they operate: i) in the manner described previously, with artificial increase in the number of echoes, when the propagation channel generates only a single significant path (p=1) by itself; and ii) in a conventional manner in the presence of multipaths (p>1).
[0063] This makes it possible to reserve the use made of the calculation resources of the receiver for cases where the gain afforded by the procedure is largest. | A spread spectrum modulator converts input sequences composed of digital symbols into n≧2 spread-spectrum sequences. The spread spectrum modulator can generate spreading code and can combine the spreading code with the input sequences to produce the n spread spectrum sequences for transmission from n respective antennas of a radio transmitter. Each spread spectrum sequence corresponds to a sum of at least two contributions mutually shifted by a time substantially less than the duration of a symbol, each contribution being the product of a version of one of the n input sequences times the spreading code. | 7 |
RELATED PATENTS
This application is a continuation-in-part of U.S. patent application Ser. No. 08/591,337, filed Jan. 25, 1996, now abandoned.
FIELD OF THE INVENTION
The present invention relates to surgical fasteners. More particularly, the present invention relates to improved surgical fasteners of the type which are secured by surgical applicators. In even greater particularity, the present invention relates to improvements in surgical staples and clips.
BACKGROUND OF THE INVENTION
Surgical fasteners, including clips and staples, and methods of applying these fasteners are well known in the art. Surgical fasteners can be used to close incisions or wounds, or to clamp vessels or ducts to prevent fluid flow. Surgical applicators used to apply these fasteners comprise various designs depending on the use to which the fasteners are employed. For example, a clip applicator is typically a pistol-shaped vise used where a vessel or duct must be sealed. The clip is directed to the location of application and then the vise secures the clip, collapsing and sealing the vessel. A surgical stapler is typically used where an incision or wound must be closed. A surgical stapler typically employs an anvil to form the fastener during application. With increasing use and improvement of various surgical applicators, fasteners have also improved. Some examples of surgical fasteners are found in U.S. Pat. Nos. 4,407,286; 4,489,875; and 4,932,960.
In the '286 patent, Noiles et al. disclose a surgical staple which is designed to reduce the tendency of the staple to slip off the anvil during application or to adhere to the anvil after application. In the '875 patent, Crawford et al. disclose a self-centering staple to remedy the problem of misalignment of the staple during application. In the '960 patent, Green et al. disclose a bioabsorbable fastener designed for elastic expansion to prevent breakage. Although the foregoing surgical fasteners, as well as others known in the art, have addressed and remedied many problems encountered with the use of these fasteners, there still exist problems accompanying their use.
One such problem is the slippage of fasteners at the point of their application in the tissue. During surgery it is frequently required to shut off fluid transfer to areas, thus fasteners are often placed around blood vessels or other structures to achieve this. For example, in cases where polyps are to be removed, fasteners are typically applied to the base of the structure to shut off fluid transfer and the polyp is removed. The fastener is left in place during the healing process to prevent fluid loss. As hydrostatic pressure increases due to the blockage, fasteners tend to slip away from the pressurized area which can result in fastener displacement and fluid loss or hemorrhage. Another problem seen with currently used fasteners concerns the closure of the fastener itself. During application of the fastener, the typical U or V-shaped designs often result in non-uniform closure of the fastener over the vessel, which again can lead to fastener displacement as well as fluid loss or hemorrhage. To avoid these problems, the fastener is tightly fastened into the tissue encompassed by the fastener, which still does not guarantee against slippage. In addition, in surgeries where fasteners are employed to temporarily shut off blood flow through a vessel, this form of application can cause irreparable injury to the vessel.
From the foregoing it may be seen that a need exists for an improved surgical fastener which is designed to resist displacement once secured to the tissue.
SUMMARY OF THE PRESENT INVENTION
It is the object of the present invention to provide an improved surgical fastener of the type used in surgical applicators which resists displacement once secured to the tissue.
It is another object of the present invention to provide a fastener which can be used in surgical applicators presently available.
These and other objects of the present invention are accomplished through the use of a surgical fastener which has been modified to enhance the gripping capability of the fastener once secured. The fastener can have apertures therethrough or the surface can be knurled, crimped, etched with a laser, layered with an abrasive coating, sand blasted, punched, notched, or modified in any other manner which enhances the grip of the fastener when secured. Additionally, the fastener can be formed from or coated with a magnetic material, which provides additional holding power to maintain the clip closed after it has been secured into the tissue. For purposes of this disclosure, a knurled surface refers to a surface which has been roughened to provide an enhanced grip. Examples of knurling include serrations, dimples, protrusions, cross-hatches, grooves, and flutes pressed into a surface. The abrasive coating is a material such as non-toxic paint containing a plurality of solid particles wherein these particles form protrusions in the coating once applied to the fastener. The modification can be continuous over the entire surface of the fastener or it can be only on the tissue contacting surface, and can additionally have modified regions intermixed with unmodified regions. During the application of the fastener to the target tissue, the tissue conforms to the modified surface of the fastener. This results in resistance to slippage because the fastener surface presses into the tissue causing depressions in the tissue. Subsequently, tissue edema and growth encapsulates and integrates into deformities in the fastener. An alternate embodiment includes a double wall to reinforce the fastener when secured.
These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
A surgical fastener embodying features of my invention is described in the accompanying drawings which form a portion of this disclosure and wherein:
FIG. 1 is a perspective view of a square-cornered U-shaped fastener before application.
FIG. 2 is a perspective view of the fastener of FIG. 1 where the surface has been knurled with a cross-hatch design.
FIG. 3 is a perspective view of the fastener of FIG. 1 where the surface is dimpled.
FIG. 4 is a perspective view of the fastener of FIG. 1 where the surface has protrusions.
FIG. 5 is a perspective view of the fastener of FIG. 1 where the surface has linear grooves or flutes.
FIG. 6 is a perspective view of the fastener of FIG. 1 where the surface has curvilinear grooves or flutes.
FIG. 7 is a perspective view of the fastener of FIG. 1 where the surface has been etched with a laser.
FIG. 8 is a perspective view of the fastener of FIG. 1 where the surface has been layered with an abrasive coating.
FIG. 9 is a perspective view of the fastener of FIG. 1 where the fastener has apertures therethrough.
FIG. 10 is a perspective view of the fastener of FIG. 1 where the fastener has been crimped.
FIG. 11 is a perspective view of the fastener of FIG. 1 where the edges of the fastener have been notched.
FIG. 12 is a perspective view of the fastener of FIG. 4 clamped around a blood vessel to prevent fluid transfer.
FIG. 13 is a perspective view of the fastener of FIG. 4 secured into tissue for maintaining closure of an incision.
FIG. 14 is a perspective view of an alternate embodiment showing a linear shaped fastener before application.
FIG. 15 is a perspective view of an alternate embodiment showing a V-shaped fastener before application.
FIG. 16 is a perspective view of an alternate embodiment showing an alternate U-shaped fastener before application.
FIG. 17 is a perspective view of an alternate embodiment showing an alternate U-shaped fastener before application.
FIG. 18 is a perspective view of an alternate embodiment showing a C-shaped fastener before application.
FIG. 19 is a perspective view of an alternate embodiment showing a double-walled fastener having an inner V-shaped portion before application.
FIG. 20 is a perspective view of an alternate embodiment showing a double-walled fastener having an inner U-shaped portion before application.
FIG. 21 is a perspective view of an alternate embodiment showing a double-walled fastener having an inner oval-shaped portion before application.
FIG. 22 is a perspective view of an alternate embodiment showing a double-walled fastener having an alternate inner V-shaped portion before application.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A more complete understanding of the invention may be obtained by reference to the accompanying drawings wherein the fastener, according to the embodiment illustrated in FIG. 1, is a square-cornered U-shaped member 10 having a base 11 and at least two parallel legs 12. The preferred embodiment is composed of titanium or stainless steel, although other metals, plastics, or ceramics can be used, as well as malleable wire. The preferred embodiment has a square cross-section, although the cross-section can be round or have any polygonal shape. Other embodiments of the present invention include a linear shaped member shown in FIG. 14, a V-shaped member shown in FIG. 15, other U-shaped members shown in FIG. 16 and FIG. 17, or a C-shaped member shown in FIG. 18. Another beneficial feature is a novel double wall, which acts to reinforce the fastener when secured. Embodiments of the present invention illustrating the double wall feature are shown in FIGS. 19-22, discussed in further detail hereinbelow. The embodiment of choice can depend on the personal preference of the user as well as the procedures for which the fasteners are to be used.
Typically, fasteners embodying features of my invention are formed from a sheet, or wire, of titanium or stainless steel which has been modified with a texturizing feature. Moreover, the fasteners can be formed from or coated with a magnetic material, which provides additional holding power to maintain the clip closed after it has been secured into the tissue. The sheets or wires are pulled from preformed rolls having a thickness usually between 0.015 to 0.025 inches. As the sheet or wire is pulled from the roll, it is pulled though a device for texturizing the sheet or wire. This texturizing device can be a crimping mechanism for crimping the sheet or wire; a knurling mechanism for pressing serrations, dimples, protrusions, cross-hatches, grooves, or flutes into the surface of the sheet or wire; an applicator for applying a non-toxic abrasive coating containing a plurality of solid particles to the surface of the sheet or wire; a series of lasers for etching into, or forming apertures through, the sheet or wire; a sand blasting chamber for pitting the surface of the sheet or wire; or a mechanical punch for punching dimples into, or apertures through, the sheet or wire. All the foregoing texturizing devices are well known in the various arts of manufacturing and are not shown. The sheet or wire can have the texturizing feature placed on only one side or on both sides. In addition, the texturizing feature can be continuous or it may be intermixed with unmodified regions.
Some illustrations of the texturizing features include a cross-hatch design as illustrated in FIG. 2, dimples as illustrated in FIG. 3, protrusions as illustrated in FIG. 4, linear grooves as illustrated in FIG. 5, curvilinear grooves as illustrated in FIG. 6, etchings from a laser as illustrated in FIG. 7, a layer of an abrasive coating as illustrated in FIG. 8, apertures from a mechanical punch or laser as illustrated in FIG. 9, crimping as illustrated in FIG. 10, or pitting from sand blasting as illustrated in FIGS. 19-22. In addition, the edges of the fasteners can have notches as illustrated in FIG. 11, which result from forming the dimples or apertures along a line where the individual fasteners will subsequently be separated. Some of the modifications are only effective to prevent slippage in one direction, such as the linear grooved surface of FIG. 5. The grooves of FIG. 5 are shown longitudinal along the fastener in order to prevent slippage of the fastener along the longitudinal of a blood vessel or the like, but could as easily be transverse along the fastener if another result was desired.
After the texturizing feature has been added, the sheet or wire is pulled into a cutting device, typically comprising a die having a plurality of longitudinal and transverse knives if sheets are used. As the die is actuated into contact with the sheet, the longitudinal knives cut the sheet into a plurality of bands, usually between 0.20 to 0.35 inches, which is to become the length of the fasteners. Simultaneously, the transverse knives cut into, but not quite through, the sheet to form a plurality of fasteners, each fastener having a width usually between 0.015 to 0.030 inches. The individual fasteners are not separated from the band at this point but are not securely attached to each other and could be easily separated by hand. In the case of wire, the wire is cut into a plurality of members having a length usually between 0.20 to 0.35 inches, which is to become the length of the fasteners. The wire members are subsequently juxtaposed to form bands for further processing. If the embodiment of the fasteners is linear shaped as shown in FIG. 14, then the fasteners are packaged with a predetermined number of fasteners per package and distributed. However, if the fasteners are to be formed into the other embodiments shown in FIGS. 1, and 15-22, then the bands of fasteners are processed further.
After leaving the cutting device, the bands of fasteners are pulled into a press where an upper plate having a plurality of linear ridges presses the bands into a reciprocal lower plate having a plurality of linear grooves corresponding to the ridges in the upper plate. The number of ridges or grooves equals the number of bands so that each band is pressed into only one groove. The shape of the groove complements the shape of the ridge so that when a band of fasteners is pressed between the ridge and groove, the band of fasteners will take on the form of the ridge or groove, which corresponds to the embodiments shown in FIGS. 1, and 15-18. The fasteners are then packaged with a predetermined number of fasteners per package and distributed.
To make the embodiments illustrated in FIGS. 19-22, the fasteners are formed such that the bands are substantially wider (i.e., the length of the fastener) than the fasteners described hereinabove. After formation as described above, the distal ends of the elongated arms are folded back to form the inner wall 11 of the fastener. The distal ends are preferably folded in such a manner that the fastener ends 12 are in contact with each other. The outer wall 13 is preferably U-shaped, such that the outer portions 14 of the arms are parallel to each other, although this is not critical. The inner wall 11 of this embodiment can have various shapes, depending on the personal preference of the user as well as the procedures for which the fasteners are to be used. A fastener having an inner V-shaped wall is shown in FIG. 19; a fastener having an inner U-shaped wall is shown in FIG. 20; a fastener having an inner oval-shaped, or modified C-shaped, wall is shown in FIG. 21; and a fastener having an alternate inner V-shaped wall is shown in FIG. 22. It is to be understood that the fasteners of this embodiment are to be used in the surgical devices already existing. Accordingly, it may be seen that the addition of a secondary wall will diminish the space within the crimping or clamping device such that an additional mass of metal is compressed. By compressing the greater mass within the same volume a more certain seal is achieved. Note that the fastener walls are not merely thickened but formed in discrete segments to enhance the engagement about the vessel by selection of the particular inner configuration as shown.
The fasteners of the present invention can be used in surgical staplers utilizing anvils or in surgical applicators utilizing a vise. Application of surgical fasteners has been well documented in the prior art and will not be repeated here. A good example of the application of fasteners with an anvil type surgical stapler was discussed by Noiles et al. in U.S. Pat. No. 4,407,286. The present discussion will focus on the fastener during and after application into the tissue. As the fastener is secured to close incisions or wounds, or to clamp vessels or ducts to prevent fluid flow, the novel features of the present invention become apparent. As the fastener closes around tissue, the tissue forms about the texturizing features. Since the interface between the fastener and the tissue is not smooth, but rather rough and abrasive, the fastener will resist displacement arising from hydrostatic pressure, movement of adjacent tissues, or other occurrences which would tend to displace the fastener. A fastener embodying features of my invention is shown secured to a blood vessel in FIG. 12 and maintaining closure of an incision in FIG. 13. Furthermore, the embodiment comprising the double wall feature illustrated in FIGS. 19-22 has the added benefit of an outer wall 13 to promote uniform compression of the inner wall 11 during application of the fastener. During application of presently used fasteners, the resistance from tissue can deform the fasteners, such that there is not uniform closure. This can subsequently lead to displacement of the fastener and fluid loss or hemorrhage. The outer wall 13 of the present invention acts to bolster the inner wall 11 during application of the fastener so that the inner wall will compress properly over the tissue, and subsequently adds fortification to the inner wall to prevent deformation from increasing hydrostatic pressure in the tissue.
It is to be understood that the form of the invention shown is a preferred embodiment thereof and that various changes and modifications may be made therein without departing from the spirit of the invention or scope as defined in the following claims. | An improved surgical fastener of the type used in a surgical applicator which has been modified to enhance the gripping capability of the fastener once secured. The fastener can have apertures therethrough or the surface can be knurled, crimped, etched with a laser, layered with an abrasive coating, sand blasted, punched, notched, or modified in any other manner which enhances the grip of the fastener when secured. Additionally, the fastener can be formed from or coated with a magnetic material, which provides additional holding power to maintain the clip closed after it has been secured into the tissue. An alternate embodiment includes a double wall to reinforce the fastener when secured. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to lubricating structures for compressors, and more particularly, to improvements in circulation passages for lubricating oil in compressors that employ swash plates.
2. Description of the Related Art
A typical variable displacement compressor that employs a swash plate has a cylinder bore and a piston accommodated therein. A compression chamber is defined in the cylinder bore by the piston. The piston is coupled to the swash plate by means of shoes. The swash plate is arranged in the crank chamber about a drive shaft. A hinge mechanism supports the swash plate in a manner such that it is inclined in accordance with the difference between the pressure in the crank chamber and the pressure acting on the face of the piston. In this type of compressor, the swash plate is moved to a minimum inclination position at which its inclination becomes minimal with respect to a plane perpendicular to the drive shaft (the state in which the compressor displacement is minimal). When the swash plate is located at the minimum inclination position, lubricating oil, which is contained in a refrigerant, is conveyed from the compression chamber to the crank chamber through a clearance defined between the piston and the wall of the cylinder bore to lubricate the swash plate and the shoes. With regard to the swash plate, a considerable amount of load is applied to a portion corresponding with the hinge mechanism in the axial direction of the drive shaft. The load applied to this portion is greater than the load applied to other portions of the swash plate. Accordingly, it is particularly important that the portion receiving the heavy load be sufficiently lubricated to improve the durability of the swash plate.
The swash plate is provided with a shaft hole to insert the drive shaft therethrough. When machining a workpiece to form the swash plate, a reference hole extending parallel to the shaft hole is provided in addition to the shaft hole. The workpiece, which is cast and disk-like, is secured to a jig. The jig is fixed on a table of a numerically controlled (NC) milling machine. The workpiece is machined by a grinding stone that is attached to a spindle of the milling machine. The workpiece must be fixed to the jig so as to prevent it from rotating when undergoing machining. Thus, a center shaft projecting from the jig is inserted through the shaft hole of the workpiece while a positioning pin projecting from the jig is inserted through the reference hole. In this manner, the workpiece is supported at two locations by the jig to prevent rotation of the workpiece. This enables stable machining of the workpiece when forming the swash plate.
As described above, the lubricating oil contained in the refrigerant is conveyed from the compression chamber toward the crank chamber via the clearance defined between the piston and the wall of the cylinder bore. When the lubricating oil leaks into the crank chamber, the oil advances along the surface of the swash plate toward the shoes and then lubricates between the swash plate and the shoes. However, the refrigerant containing the lubricating oil flows into the reference hole. This affects the flow of the lubricating oil in an undesirable manner. Insufficient lubrication of the region receiving the heaviest load results in early wear of the plate. Such insufficient lubrication is especially troublesome in compressors that do not use clutches (clutchless compressors) such as those described in Japanese Unexamined Patent Publication Nos. 3-37378 and 7-286581.
In a typical clutchless compressor, it is important to prevent excessive compressor displacement when cooling is not required and to prevent frost from forming in the associated evaporator. The circulation of refrigerant through the external refrigerant circuit is stopped when cooling is not required or when there is a possibility of the formation of frost. In the compressors of Japanese Unexamined Patent Publication Nos. 3-37378 and 7-286581, the circulation of refrigerant in the external refrigerant circuit is stopped by impeding the flow of refrigerant gas entering the suction chamber of the compressor from the external refrigerant circuit. In these compressors, when the flow of refrigerant gas from the external refrigerant circuit to the suction chamber is impeded, the swash plate is moved to the minimum inclination position. If the flow of refrigerant gas from the external refrigerant circuit to the suction chamber is commenced, the inclination of the swash plate is increased from the minimum inclination. When the swash plate is located at the minimum inclination position, the refrigerant in the external refrigerant circuit does not return to the compressor. In this case, lubrication of the interior of the compressor is carried out by the lubricating oil contained in the refrigerant that circulates within the compressor. The refrigerant passing through the clearance is part of the refrigerant circulating within the compressor. Thus, when the lubricating oil that is contained in the circulating refrigerant becomes insufficient, it is difficult to avoid early wear since the swash plate is constantly rotated during operation of the external drive source that drives the compressor.
SUMMARY OF THE INVENTION
Accordingly, it is an objective of the present invention to provide a lubricating structure that ensures long life of a swash plate in a compressor, which inclinably supports the swash plate in a crank chamber and which controls the inclination of the swash plate in accordance with the difference between the pressure in the crank chamber and the pressure acting on the face of a piston.
It is another objective of the present invention to provide a lubricating structure for a compressor that enables efficient lubrication of the swash plate at portions receiving a high degree of load.
It is a further objective of the present invention to provide a lubricating structure for a compressor that employs a swash plate having superior strength.
To achieve the above objectives, an improved lubricating structure of a compressor is disclosed. A swash plate is tiltably supported on the drive shaft for integral rotation therewith. A plurality of pistons are operably coupled to the swash plate. The rotation of the swash plate is converted to reciprocal movement of each piston in an associated cylinder bore to compress and discharge gas that contains oil. A clearance is defined by the cylinder bore and the piston enabling the compressed gas to flow out from the cylinder bore to the swash plate. The swash plate has an operation area that receives greatest compression load based on reaction force of the compressed gas acting on the piston when the swash plate rotates. The swash plate has at least one bore for attaching the swash plate to a jig when the swash plate is ground during its manufacturing process. The bore is arranged to allow the gas flow out to the swash plate from the cylinder bore through the clearance to flow to the operation area.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention that are believed to be novel are set forth with particularity in the appended claims. The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:
FIG. 1 is a cross-sectional side view showing a compressor according to a first embodiment of the present invention;
FIG. 2 is a cross-sectional view taken along line 2--2 in FIG. 1;
FIG. 3 is a cross-sectional view taken along line 3--3 in FIG. 1;
FIG. 4 is a cross-sectional view taken along line 4--4 in FIG. 1;
FIG. 5 is a cross-sectional side view showing the entire compressor when the swash plate is arranged at the minimum inclination position;
FIG. 6 is a perspective view showing the manufacturing method of the swash plate;
FIGS. 7(A) and 7(B) show a second embodiment according to the present invention. FIG. 7(A) is a cross-sectional view taken along a location corresponding to FIG. 2, and FIG. 7(B) is a perspective view showing the rear side of the swash plate;
FIGS. 8(A) and 8(B) show a third embodiment according to the present invention. FIG. 8(A) is a perspective view showing the front side of the swash plate, and FIG. 8(B) is a perspective view showing the rear side of the swash plate; and
FIGS. 9(A) and 9(B) show a fourth embodiment according to the present invention. FIG. 9(A) is a perspective view showing the front side of the swash plate, and FIG. 9(B) is a perspective view showing the rear side of the swash plate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A clutchless variable displacement compressor according to a first embodiment of the present invention will hereafter be described with reference to FIGS. 1 to 6.
As shown in FIG. 1, a front housing 12 is fastened to the front end of a cylinder block 11. A rear housing 13 is fastened to the rear end of the cylinder block 11. First, second, and third valve plates 14, 15, 16 and a retainer plate 17 are provided between the rear housing and the cylinder block 11.
A crank chamber 121 is defined in the front housing 12. A drive shaft 18 extends through the front housing 12 and the cylinder block 11 and is rotatably supported. The front end of the drive shaft 18 projects outward from the housing 12. A pulley 19 is secured to the projecting end of the drive shaft 18. The pulley 19 is operably connected to a vehicle engine (not shown) by a belt 20. The front housing 12 supports the pulley 19 by means of an angular bearing 21. The angular bearing 21 receives both axial and radial loads that are applied to the front housing 12 by the pulley 19.
A lug plate 22 is connected to the drive shaft 18. A disk-like swash plate 23 is provided on the drive shaft 18. The swash plate 23 is inclinable and slidable in the axial direction of the drive shaft 18. A shaft hole 231 extends through the center of the swash plate 23. The drive shaft 18 is inserted through the shaft hole 231 to enable relative sliding between the swash plate 23 and the shaft 18. The middle of the shaft hole 231 in the axial direction of the drive shaft 18 has a substantially circular cross-section. The diameter at the middle (circular portion) of the shaft hole 231 is about the same as the diameter of the drive shaft 18. The shaft hole 231 is flared toward the rear side of the swash plate 23 (toward the cylinder block 11) from the circular portion. The shaft hole 231 is also flared toward the front side of the swash plate 23 (toward the front housing 12) from the circular portion. The shape of the shaft hole 231 enables the swash plate to slide and incline with respect to the drive shaft 18 without interference.
As shown in FIG. 3, coupling pieces 24, 25 are fixed to the swash plate 23. Guide pins 26, 27 are secured to the coupling pieces 24, 25, respectively. Guide spheres 261, 271 are provided at the distal end of the guide pins 26, 27. An arm 221 projects from the lug plate 22. A pair of guide holes 222, 223 are defined in the arm 221. The guide spheres 261, 271 are slidably fitted into the guide holes 222, 223, respectively. The arm 221 cooperates with the pair of guide pins 26, 27 to permit the swash plate 23 to incline in the axial direction of the drive shaft 18 and to integrally rotate the swash plate 23 with the drive shaft 18.
The guide spheres 261, 271 are guided in the associated guide holes 222, 223 as the guide spheres 261, 271 slide therein while the swash plate 23 is supported by the drive shaft 18 as the plate 23 slides along the shaft 18. During its inclination, the swash plate 23 inclines about its upper section, as viewed in FIG. 1, which is where the piston 37 is moved to a top dead center position. The inclination of the swash plate 23 with respect to a direction perpendicular to the drive shaft 18 becomes small as the center of the swash plate moves toward the cylinder block 11.
Annular sliding surfaces 232, 233 are defined at the periphery of the front and rear sides of the swash plate 23. A reference hole 234 extends in a direction perpendicular to the sliding surfaces 232, 233 at a location that is inward from the sliding surfaces 232, 233. As shown in FIG. 2, the reference hole 234 is located at a position spaced from the region located between the guide pins 26, 27.
The reference hole 234 is used to grind the swash plate 23. For example, the reference hole 234 is used when grinding the sliding surfaces 232, 233. As shown in FIG. 6, the swash plate 23 is produced from a cast, disk-like workpiece 23D. The shaft hole 231 and the reference hole 234 are formed when casting the workpiece 23D. The workpiece 23D is ground by first securing the workpiece 23 to a jig 51. A center shaft 511 and a positioning pin 512 project from the jig 51. The center shaft 511 is inserted into the shaft hole 23 while the positioning pin 512 is inserted into the reference hole 23D. Accordingly, the workpiece 23D is supported at two locations on the jig 51. This prevents the workpiece 23D from rotating with respect to the jig 51. The jig 51 is fixed to a table of a numerically controlled (NC) milling machine (not shown). The peripheral portion on one side of the workpiece 23D is ground by a grinding stone (not shown) attached to the NC grinding machine to finish the sliding surface 232 of the swash plate 23. After the sliding surface 232 is finished, the workpiece 23D is reversed on the jig 51 and ground again to form the sliding surface 233.
A compression spring 28 is arranged between the lug plate 22 and the swash plate 23. The spring 28 urges the swash plate 23 in a direction that decreases the inclination of the swash plate 23.
As shown in FIGS. 1 and 5, an accommodating hole 29 extends through the center of the cylinder block 11 in the axial direction of the drive shaft 18. A cup-like plunger 30 is slidably accommodated in the accommodating hole 29. A compression spring 31 is arranged between the plunger 30 and an end step of the accommodating hole 29. The spring 31 urges the plunger 30 toward the swash plate 23.
The rear end of the drive shaft 18 is inserted into the plunger 30. A radial bearing 32 is supported by the inner surface of the plunger 30. The radial bearing 32 is slidable with respect to the drive shaft 18. A snap ring 33 is arranged in the plunger 30 to prevent the radial bearing 32 from falling out of the plunger 30. The rear end of the drive shaft 18 is supported by the wall of the accommodating hole 29 by means of the radial bearing 32 and the plunger 30.
A suction passage 34 extends through the center of the rear housing 13. The axis of the suction passage 34 coincides with the axis of the plunger 30. The suction passage 34 is connected with the accommodating hole 29. A positioning surface 35 is defined about the opening of the suction passage 34 on the valve plate 15. The end face of the plunger 30 abuts against the positioning surface 35. The abutment between the plunger 30 and the positioning surface 35 restricts the plunger 30 from moving further away from the swash plate 23.
A thrust bearing 36 is slidably arranged on the drive shaft 18 between the swash plate 23 and the plunger 30. The force of the spring 31 keeps the thrust bearing 36 held between the swash plate 23 and the plunger 30. As the swash plate 23 moves toward the plunger 30, the inclination of the swash plate 23 is conveyed to the plunger 30 by means of the thrust bearing 36. This moves the plunger 30 toward the positioning surface 35 against the force of the spring 31 until the plunger 30 abuts against the positioning surface 35. The thrust bearing 36 prevents the rotation of the swash plate 23 from being conveyed to the plunger 30.
A plurality of cylinder bores 111 extend through the cylinder block 11. A single-headed piston 37 is accommodated in each cylinder bore 111. Each piston 37 is coupled to the swash plate 23 by shoes 38. The rotating movement of the swash plate 23 is converted to reciprocating movement of each piston 37 by means of the shoes 38. This moves the piston 37 back and forth in each cylinder bore 111.
As shown in FIGS. 1 and 4, a suction chamber 131 and a discharge chamber 132 are defined in the rear housing 13. Suction ports 141 and discharge ports 142 are defined in the first valve plate 14. Suction valves 151 are provided in the second valve plate 15. Discharge valves 161 are provided in the third valve plate 16. When each piston 37 moves away from the valve plates 14, 15, 16, the refrigerant gas in the suction chamber 131 opens the associated suction valve 151 and enters the compression chamber 113 defined in the cylinder bore 111 through the associated suction port 141. When the piston 37 moves toward the valve plates 14, 15, 16, the refrigerant gas in the compression chamber 113 is compressed and then discharged into the discharge chamber 132 through the associated discharge port 142 as the gas opens the associated discharge valve 161. When opened, the discharge valve 161 abuts against a retainer 171 provided on the retainer plate 17. This restricts the opening of the discharge valve 161.
A thrust bearing 39 is arranged between the lug plate 22 and the front housing 12. The thrust bearing 39 receives the compression reaction that is produced in each compression chamber 113 and applied to the lug plate 22 by way of the piston 37, the shoes 38, the swash plate 23, the coupling pieces 24, 25, and the guide pins 26, 27. Accordingly, heavy load resulting from the compression reaction acts on the sliding surface 232 of the swash plate 23. The region on the swash plate 23 that receives the heaviest load is denoted as F in FIGS. 1 and 2.
The maximum reaction force is applied to the swash plate 23 at a location that is offset in the rotating direction of the swash plate 23 for a predetermined angle from the portion of the swash plate 23 that moves the pistons to the 37 top dead center position. The degree of the offset angle varies in accordance with the rotating speed and the compression ratio of the compressor. Accordingly, it is preferable that the guide pins 26, 27 be arranged so as to straddle the region at which the maximum reaction force varies. The region F corresponding to the region between the two guide pins 26, 27 is defined as a heavy load region. As described above, the heavy load region F is offset in the rotating direction of the swash plate 23 from the portion corresponding to the top dead center position. However, the swash plate 23 employed in the present invention is rotated in both forward and reverse directions. Thus, the two guide pins 26, 27 are located symmetrically with respect to a plane that includes the axis of the rotary shaft 18 and intersects the portion on the swash plate 23 corresponding to the top dead center position.
The suction chamber 131 is connected with the accommodating hole 29 through an inlet 143. When the plunger 30 abuts against the positioning surface 35, the inlet 143 becomes disconnected from the suction passage 34. A conduit 40 extends through the drive shaft 18. The crank chamber 121 is connected to the inside of the plunger 30 through the conduit 40. As shown in FIGS. 1 and 5, a pressure releasing hole 301 extends through the wall of the plunger 30. The inside of the plunger 30 is connected to the accommodating hole 35 by the pressure releasing hole 301.
As shown in FIG. 1, the discharge chamber 132 is connected to the crank chamber 121 by a pressurizing passage 41. An electromagnetic valve 42 is provided in the pressurizing passage 41. The valve 42 includes a solenoid 43, a valve body 44, and a valve hole 421. When the solenoid 43 is excited, the valve body 44 closes the valve hole 421. When the solenoid 43 is de-excited, the valve body 44 opens the valve hole 421. In this manner, the valve 42 selectively connects and disconnects the discharge chamber 132 with the crank chamber 121.
The suction passage 34, through which refrigerant gas is drawn in, and an outlet 112 of the discharge chamber 132, from which the refrigerant gas is discharged, are connected to each other by an external refrigerant circuit. The external refrigerant circuit 45 is provided with a condenser 46, an expansion valve 47, and an evaporator 48. The expansion valve 47 controls the flow rate of the refrigerant in accordance with changes in the gas temperature at the outlet side of the evaporator 48. A temperature sensor 49 is provided in the vicinity of the evaporator 48. The temperature sensor 49 detects the temperature of the evaporator 48 and sends a signal corresponding to the detected temperature to a computer C.
In response to the signal from the temperature sensor 49, the computer C excites or de-excites the solenoid 43. When an operating switch 50 is turned on, the computer C de-excites the solenoid 43 if the temperature detected by the temperature sensor 49 becomes lower than a predetermined value. The predetermined temperature corresponds to a temperature at which frost may start forming in the evaporator 48. When the operating switch 50 is turned off, the computer C de-excites the solenoid 43.
In the state shown in FIG. 1, the solenoid 43 is excited and the pressurizing passage 41 is thus closed. Accordingly, the flow of high-pressure refrigerant gas from the discharge chamber 132 to the crank chamber 121 is impeded. In this state, the refrigerant gas in the crank chamber 121 continuously flows into the suction chamber 131 by way of the conduit 40 and the pressure releasing hole 301. This lowers the pressure in the crank chamber 121 until it becomes close to the low pressure in the suction chamber 131 (i.e., suction pressure). This increases the inclination of the swash plate 23. When the swash plate 23 inclines to a maximum inclination position, a balance weight 235 provided integrally with the swash plate 23 abuts against a projection 224 projecting from the lug plate 22. This restricts further movement of the swash plate 23 from the maximum inclination position. When the swash plate 23 is held at the maximum inclination position, the compressor displacement becomes maximum.
When the ambient temperature decreases, the load of the compressor becomes small. If the swash plate 23 is held at the maximum inclination position in this state, the temperature of the evaporator 48 falls and becomes close to a temperature at which frost starts forming. The temperature sensor 49 sends a signal corresponding to the temperature of the evaporator 48 to the computer C. When the temperature becomes lower than the predetermined temperature, the computer C de-excites the solenoid 43. This opens the pressurizing passage 41 and connects the discharge chamber 132 with the crank chamber 121. Accordingly, the high-pressure refrigerant gas in the discharge chamber 132 is drawn into the crank chamber 121 through the pressurizing passage 41. This increases the pressure in the crank chamber 121. The pressure increase in the crank chamber 121 shifts the swash plate 23 to a minimum inclination position. The swash plate 23 is also shifted to the minimum inclination position when the switch 50 is turned off and the solenoid 43 is de-excited by the computer C.
When the inclination of the swash plate 23 becomes minimum, the plunger 30 abuts against the positioning surface 35 and closes the suction passage 34. Since the swash plate 23 inclines gradually and moves the plunger 30 accordingly, the plunger 30 serves to restrict the flow of the gas passing through the suction passage 34. Thus, the flow rate of the refrigerant gas flowing from the suction passage 34 to the suction chamber 131 gradually becomes small as the effective cross-sectional area of the passage therebetween decreases. This gradually decreases the amount of refrigerant gas drawn into each compression chamber 113 from the suction chamber 131. Accordingly, the discharge pressure gradually becomes smaller and the load torque of the compressor is prevented from changing suddenly. As a result, the change in load torque of the compressor is small when the compressor displacement is shifted from maximum to minimum. This eliminates shocks that may be produced by changes in the load torque.
As shown in the state of FIG. 5, when the plunger 30 abuts against the positioning surface 35, the suction passage 34 is completely closed. Hence, the flow of refrigerant gas from the external refrigerant circuit 45 to the suction chamber 131 is impeded. In other words, the circulation of the refrigerant in the external refrigerant circuit 45 is stopped. The minimum inclination position of the swash plate 23 is restricted by the abutment between the plunger 30 and the positioning surface 35.
When located at the minimum inclination position, the inclination of the swash plate 23 with respect to a plane perpendicular to the drive shaft 18 is slightly greater than zero degrees. The swash plate 23 is located at the minimum inclination position when the plunger 30 is arranged at a closing position at which the plunger 30 disconnects the suction passage 34 from the accommodating hole 29. The plunger 30 cooperates with the swash plate 23 and moves between the closing position and an opening position. Since the minimum inclination of the swash plate 23 is slightly greater than zero degrees, discharge of refrigerant gas from each compression chamber 113 to the discharge chamber 132 continues even when the swash plate 23 is located at the minimum inclination position. The refrigerant gas discharged into the discharge chamber 121 from the compression chambers 113 passes through the pressurizing passage 41 and flows into the crank chamber 121. The refrigerant gas in the crank chamber 121 flows into the suction chamber 131 by way of the conduit 40 and the pressure releasing hole 301. The refrigerant gas in the compression chamber 131 is drawn into each compression chamber 113 and discharged into the discharge chamber 132. In other words, a circulation passage of the refrigerant gas is defined in the compressor when the swash plate 23 is located at the minimum inclination position. The circulation passage extends between the discharge chamber 132 (discharge pressure zone), the pressurizing passage 41, the crank chamber 121, the conduit 40, the pressure releasing hole 301, the accommodating hole 29 (suction pressure zone), the suction chamber 131 (suction pressure inzone), and the compression chambers 113. The pressure in the discharge chamber 132, the crank chamber 121, and the suction chamber 131 differs from one another. This enables the refrigerant gas to circulate through the circulation passage. The circulating refrigerant gas lubricates the interior of the compressor with the lubricating oil suspended therein.
A clearance is defined between each piston 37 and the wall of the associated cylinder bore 111. As indicated by the arrow R in FIG. 5, the refrigerant gas in the compression chamber 113 leaks into the crank chamber 121 during the discharge stroke of the piston 37. Part of the lubricating oil, which is suspended in the refrigerant gas passing through the clearance, lubricates the area of contact between the swash plate 23 and the shoes 38.
When the ambient temperature increases in the state shown in FIG. 5, the load of the compressor becomes large. This increases the temperature of the evaporator 48. If the temperature of the evaporator 48 exceeds a predetermined temperature, the computer C excites the solenoid 43. This causes the electromagnetic valve 42 to close the pressurizing passage 41. Accordingly, the pressure in the crank chamber 121 is released through the conduit 40 and the pressure releasing hole 301. This decreases the pressure in the crank chamber 121 and extends the spring 31 from the compressed state shown in FIG. 5. The spring 31 separates the plunger 30 from the positioning surface 35 and increases the inclination of the swash plate 23 from the minimum inclination position. As the plunger 30 moves away from the positioning surface 35, the flow rate of the refrigerant gas drawn into the suction chamber 131 from the suction passage 34 gradually increases as the effective cross-sectional area of the passage therebetween increases. Accordingly, the 19 amount of refrigerant gas drawn into each compressing chamber 113 from the suction chamber 131 increases gradually. This, in turn, gradually increases the compressor displacement. Hence, the load torque of the compressor is not changed suddenly. As a result, the change in load torque of the compressor is small when the compressor displacement is shifted from minimum to maximum. This eliminates shocks that may be produced by changes in the load torque.
When the vehicle engine is stopped, the rotation of the swash plate 23 is stopped and the compressor is deactivated. The electromagnetic valve 42 is concurrently de-excited and the inclination of the swash plate 23 becomes minimum. Although the pressure in the compressor becomes uniform when the compressor remains deactivated, the swash plate 23 is maintained held at the minimum inclination position by the force of the spring 28. Accordingly, when the starting of the engine commences operation of the compressor, the swash plate 23 begins to rotate at the minimum inclination position. Since the load torque is minimum when the swash plate 23 is located at the minimum inclination position, the shock, which is produced when commencing operation of the compressor, is minimal.
As described above, the refrigerant gas in each compression chamber 132 leaks into the crank chamber 121 through the clearance defined between each piston 37 and the wall of the associated cylinder bore 111. Each piston 37 has a basal portion 381 that is defined at the periphery of the cylinder block 121 to couple the sliding surfaces 232, 233 of the swash plate 23 with the shoes 38. This causes the refrigerant gas to leak mainly through the portion of the clearance that is closer to the center of the cylinder block 121, as indicated by arrow R in FIG. 5. Part of the refrigerant oil that leaks from the clearance, advances along the swash plate 23 toward the sliding surface 232. This allows the refrigerant gas to be supplied to the heavy load region F, at which the compression reaction force is heaviest on the sliding surface 232. In other words, refrigerant gas is supplied to the portion corresponding to the region between the two guide pins 26, 27. The reference hole 234 is offset angularly with respect to the guide pins 26, 27. Thus, the flow of refrigerant gas from the center portion of the swash plate 23 toward the heavy load region F on the sliding surface 232 is not obstructed by the reference hole 234. Accordingly, the reference hole 234 does not hinder the lubrication of the heavy load region F.
In addition, the reference hole 234 does not extend through either one of the guide pins 26, 27 and the coupling pieces 24, 25. Thus, the strength of the guide pins 26, 27 and the coupling pieces 24, 25 remains unafected.
When the circulation of refrigerant through the external refrigerant circuit 45 is stopped, the inclination of the swash plate 23 becomes minimum. If the circulation of the refrigerant is commenced, the inclination of the swash plate 23 is increased. The swash plate 23 is constantly rotated when the external drive source is operating. Thus, the heavy load region F defined on the sliding surface 232 between the swash plate 23 and the shoes 38 must be lubricated even when the swash plate 23 is located at the minimum inclination position, that is, when the compressor displacement is minimum. When the compressor displacement is minimum, the refrigerant in the external refrigerant circuit is not returned to the compressor. In this state, the heavy load region F on the sliding surface 232 is lubricated solely by the lubricating oil suspended in the refrigerant circulating within the compressor. Accordingly, in the swash plate 23 provided with the reference hole 234 at the location described above, the lubrication of the heavy load region F is not hindered by the reference hole. This structure is especially effective in clutchless compressors.
A second embodiment according to the present invention will now be described with reference to FIGS. 7(A) and 7(B). Elements that are identical to those employed in the first embodiment will be denoted with the same reference numerals. In this embodiment, the reference hole 234 extends through the swash plate 23 on the opposite side of the shaft hole 231 with respect to the guide pins 26, 27. The reference hole 234 extends through the balance weight 235. Since the reference hole 234 is located at a position farthest from the heavy load region F, which is on the other side of the drive shaft 18, the effect that the reference hole 234 has on the lubrication of the heavy load region F is minimal.
Furthermore, the reference hole 234 extends through the balance weight 235. It is necessary to limit the diameter of the reference hole 234 to ensure the required strength in the swash plate 23. However, in the swash plate 23, the strength is highest at the location of the balance weight 235. Thus, by providing the reference hole 234 in the balance weight 235, the diameter of the reference hole 234 may be changed without having to worry about the strength of the swash plate 23.
A third embodiment according to the present invention will now be described with reference to FIGS. 8(A) and 8(B). Elements that are identical to those employed in the first embodiment will be denoted with the same reference numerals.
In this embodiment, a reference hole 236 is provided in the front side of the swash plate 23 while another reference hole 237 is provided in the rear side of the swash plate 23. Each reference hole 236, 237 is a blind hole that does not extend through the swash plate 23. The reference holes 236, 237 are located symmetrically with respect to a radial line r, which extends from the axis of the swash plate 23 to the middle point between the guide pins 26, 27. In this embodiment, the lubrication of the heavy load region F is substantially unaffected by the reference holes 236, 237 since they do not extend through the swash plate 23.
A fourth embodiment according to the present invention will now be described with reference to FIGS. 9(A) and 9(B). Elements that are identical to those employed in the first embodiment will be denoted with the same reference numerals.
In this embodiment, a reference hole 238 is provided in the front side of the swash plate 23 while a reference hole 239 is provided in the rear side of the swash plate 23. Each reference hole 238, 239 is a blind hole that does not extend through the swash plate 23. Each reference hole 238, 239 is provided along the radial line r. A guide groove 52 connecting the reference hole 238 and the sliding surface 232 is provided on the rear side of the swash plate 23. The reference hole 238 and the guide groove 52 guide the flow of refrigerant gas that leaks into the crank chamber 121 from the compression chambers 113 toward the heavy load region F on the sliding surface 232. In the same manner as the third embodiment, the lubrication of the heavy load region F on the sliding surface 232 is substantially unaffected by the reference holes 238, 239 since they do not extend through the swash plate 23. Furthermore, since the guide groove 52 guides the refrigerant gas, lubrication of the heavy load region F on the sliding surface 232 is facilitated.
The present invention is applied to clutchless variable displacement compressors in the above embodiments. However, the present invention may also be applied to variable displacement compressors that have clutches.
Although several embodiments of the present invention have been described herein, it should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention. Therefore, the present examples and embodiments are to be considered as illustrative and not restrictive and the invention is not to be limited to the details given herein, but may be modified within the scope of the appended claims. | An improved lubricating structure of a compressor is disclosed. A swash plate is tiltably supported on the drive shaft for an integral rotation therewith. A plurality of pistons are operably coupled to the swash plate. The rotation of the swash plate is converted to a reciprocal movement of each piston in an associated cylinder bore to compress and discharge gas that contains oil. A clearance is defined by the cylinder bore and the piston enabling the compressed gas to flow out from the cylinder bore to the swash plate. The swash plate has an operation area that receives greatest compression load based on reaction force of the compressed gas acting on the piston when the swash plate rotates. The swash plate has at least one bore for attaching the swash plate to a jig when the swash plate is ground during its manufacturing process. The bore is arranged to allow the gas flow out to the swash plate from the cylinder bore through the clearance to flow to the operation area. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of the filing dates of U.S. patent application Ser. No. 08/846,440, filed Apr. 30, 1997, (now U.S. Pat. No. 5,921,715, issued Jul. 13, 1999). U.S. patent application Ser. No. 09/049,627, filed Mar. 27, 1998, now U.S. Pat. No. 6,089,793 and U.S. Provisional Application Serial No. 60/086,843, filed May 27, 1998.
FIELD OF THE INVENTION
The invention relates generally to earth reinforcement. More particularly, the invention relates to a segmental retaining wall anchoring system for securing segmental retaining walls.
BACKGROUND OF THE INVENTION
Segmental earth retaining walls are commonly used for architectural and site development applications. Such walls are subjected to very high pressures exerted by lateral movements of the soil, temperature and shrinkage effects, and seismic loads. Therefore, the backfill soil typically must be braced with tensile reinforcement members.
Often, elongated structures, commonly referred to as geogrids or reinforcement fabrics, are used to provide this reinforcement. Geogrids often are configured in a lattice arrangement and are constructed of a metal or polymer, while reinforcement fabrics are constructed of woven or nonwoven polymers (e.g., polymer fibers). These reinforcement members typically extend rearwardly from the wall and into the soil. The weight of the soil constrains the fabric from lateral movement to thereby stabilize the retaining wall.
SUMMARY OF THE INVENTION
Briefly described, the present invention relates to a retaining wall anchoring system for a segmental retaining wall comprising a plurality of tieback rods adapted to be embedded into soil or rock with a proximal portion extending therefrom. The system includes at least one elongated force distribution member positionable directly adjacent the proximal portion of the tieback rods, at least one washer positionable about the proximal portions of at least one tieback rod in abutment with the force distribution member, and at least one fastener fixedly securable to the proximal portion of the tieback rod to securely clamp the washer against the force distribution member such that tensile forces imposed on the tieback rod are transmitted to the distribution member so as to distribute these forces throughout a portion of the retaining wall.
The above described apparatus therefore can be used to construct a segmental retaining wall system comprising a retaining wall having a plurality of wall blocks stacked in ascending courses with a plurality of the wall blocks being provided with interior openings that are aligned with each other to form an inner passageway within the retaining rods to securely clamp the washer against the force distribution member such that tensile forces imposed on the tieback rods are transmitted to the force distribution member so as to distribute the tensile forces throughout a portion of the retaining wall.
In addition, the apparatus can be used to construct a segmental retaining wall system comprising a retaining wall having a plurality of wall blocks stacked in ascending courses to form an interior surface and an exterior surface, a plurality of tieback rods adapted to be embedded into soil or rock with a proximal portion extending therefrom, the proximal portion of each tieback rod extending toward the interior surface of the retaining wall, at least one elongated force distribution member positioned adjacent the interior surface of the retaining wall and directly adjacent the proximal portion of at least one tieback rod, a washer positioned about the distal portion of the tieback rod in abutment with the force distribution member, a fastener fixedly secured to the proximal portion of the tieback rod to securely clamp the washer against the force distribution member, and a reinforcement member connected to the force distribution member and being securely attached to the retaining wall such that tensile forces imposed on the tieback rods are transmitted to the force distribution member and through the reinforcement member to the retaining wall so as to distribute the tensile forces throughout a portion of the retaining wall.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a retaining wall secured with an anchoring system constructed in accordance with the present invention.
FIG. 2 is a partial cross-sectional view of a retaining wall which shows a tieback connection of an anchoring system constructed in accordance with the present invention.
FIG. 3 is a partial cross-sectional view of a retaining wall secured with an anchoring system constructed in accordance with the present invention.
FIG. 4 is a partial cross-sectional view of a retaining wall which shows a tieback connection of an anchoring system constructed in accordance with the present invention.
DETAILED DESCRIPTION
Referring now in detail to the drawings, in which like numerals indicate corresponding parts throughout the several views, FIG. 1 illustrates a modular retaining wall 10 secured with a first embodiment 12 of an anchoring system constructed in accordance with the present invention. As depicted in this figure, the retaining wall 10 comprises a plurality of wall blocks 14 that are stacked atop each other in ascending courses 16 . When stacked in this manner, the wall blocks 14 together form an exterior surface 18 of the wall 10 which faces outwardly away from an earth embankment, and an interior surface 20 of the wall 10 which faces inwardly toward the embankment (FIG. 3 ). Typically, the blocks 14 are stacked in a staggered arrangement as shown in FIG. 1 to provide greater stability to the wall 10 .
Generally speaking, the blocks 14 are substantially identical in size and shape for ease of block fabrication and wall construction, although it will be understood that unidentical blocks could be used, especially for cap blocks or base blocks. In a preferred configuration, each block 14 is configured so as to mate with at least one other block 14 when the blocks are stacked atop one another to form the retaining wall 10 . This mating restricts relative movement between vertically adjacent blocks in at least one horizontal direction. To provide for this mating, the blocks 14 can include locking means 22 that secure the blocks together to further increase wall stability. More particularly, each block 14 can include a lock channel 24 and a lock flange 26 that are configured so as to positively lock with each other when the blocks 14 are stacked on top of each another as disclosed in co-pending U.S. application Ser. No. 09/049,627, which is hereby incorporated by reference into the present disclosure. When the blocks 14 include lock channels 24 and flanges 26 , the individual lock channels typically form a continuous lock channel that extends the length of the lower of two mating courses when the blocks are aligned side-by-side within each course 16 . Similarly, the lock flanges 26 form a continuous lock flange that extends the length of the upper of the mating courses 16 which is received by the continuous lock channel of the lower of the mating courses.
Although the blocks 14 preferably are provided with such locking means 22 , it will be appreciated that the anchoring system of the present invention can be used with substantially any segmental retaining wall blocks. By way of example, the present system could be used with any of the blocks produced by Anchor Wall Systems, Inc. such as any block of the Anchor Diamond® and/or Anchor Vertica® product lines, or any block disclosed in U.S. Pat. No. 5,827,015, which is hereby incorporated by reference into the present disclosure. Moreover, the present system could be utilized with the segmental blocks produced by other manufacturers such as Keystone, Mesa, Versa-Lok, Newcastle, and Piza. Irrespective of the particular configuration of the wall blocks 14 , each of the wall blocks typically includes an interior opening 32 that either extends through the block horizontally (side-to-side) or vertically (top-to-bottom). When the blocks 14 are correctly aligned in their respective courses 16 , these openings 32 form continuous elongated passageways 34 . In that, as described below, the passageways 34 typically are only used for anchoring system attachment, it is to be appreciated that only the blocks 14 that receive the system's components need be provided with such openings 32 .
As indicated in FIGS. 1 - 3 , the retaining wall 10 is secured in several predetermined points with tieback connections 36 . Typically, each tieback connection 36 is spaced approximately 10 feet apart horizontally from each other to form rows of tieback connections that are approximately 2.5 feet apart vertically from each other. Accordingly, each tieback rod 38 is embedded into the soil and/or rock in these intervals. As shown in FIG. 2, each tieback rod 38 extends through an opening 39 formed in the rear surface of its respective wall block 14 such that a proximal portion 40 of the rod 38 extends into the continuous elongated passageway. Also positioned within the passageway 34 is a tieback rod attachment mechanism 42 . The attachment mechanism 42 normally includes a pair of elongated force distribution members 44 , 46 that extend from one tieback rod 26 to the next along the passageway 34 and which are positioned above and below the tieback rods 38 as indicated in FIG. 1 . Typically, each force distribution member 44 , 46 comprises an elongated channel beam that is flanged so as to cooperate more readily with washers described below. Arranged in this manner, each passageway 34 having tieback rods 38 extending therein includes a plurality of force distribution members 44 , 46 aligned end to end both above and below the rods. To maintain parallel spacing between the force distribution members 44 , 46 , the attachment mechanism 42 can include spacers 47 that are positioned adjacent each rod 38 on both sides of the rod as indicated in FIG. 1 . Normally, the height of these spacers 47 generally approximates the diameter of the tieback rods 38 .
As shown in FIG. 2, a pair of flanged washers 48 , 50 partially surround the upper and lower pairs of force distribution members 44 and 46 , and are fitted about each tieback bar 38 . To accommodate the rearmost 50 of the washers, each wall block 14 accommodating a tieback rod 38 normally is provided with an inner channel 54 that is sized and configured for receipt of the washer 50 . Threaded onto each tieback rod 38 is a conventional threaded fastener 56 such as a nut which, when fully tightened, urges the washers 48 , 50 inwardly to securely hold the force distribution members 44 , 46 in position, thereby securing the rod to the wall 10 . Normally, this tightening is achieved by accessing the interior of the block 14 by removing a face covering portion 57 of the block. Once fully tightened, the fastener 56 can be bonded in place with epoxy to prevent its inadvertent loosening. After the fastener 56 has been fixed in place, the face covering portion 57 of the block 14 can be secured to the block so that it matches the other blocks forming the wall. Configured in this manner, each tieback connection 36 evenly distributes any forces exerted on the tieback rods 38 throughout the wall 10 to greatly improve wall integrity.
FIG. 4 illustrates a second embodiment 58 of an anchoring system constructed in accordance with the present invention. This embodiment is structurally similar to the system depicted in FIGS. 1 - 3 and described above. Accordingly, the force distribution members 44 , 46 , flanged washers 48 , 50 , as well as the fastener 56 , are used to secure the tieback rods 38 to the wall 10 . However, in this embodiment, the rods 38 are secured with a reinforcement member 60 such as a geogrid wrap instead of directly to a wall block 14 such that the reinforcement member 60 is positioned outside of but adjacent to the interior surface 20 of the wall. Because of this arrangement, the blocks 14 need not comprise interior openings 32 , as in the first embodiment. Preferred for the construction of the reinforcement member 60 is geogrid material that comprises flexible fabric composed of a polymeric material such as polypropylene or high tenacity polyester. As shown most clearly in FIG. 4, the reinforcement member 60 extends from the exterior surface 18 of the retaining wall 10 , into a lock channel 24 of the lower adjacent wall block 14 , out from the wall and into a portion of the stone fill 62 formed between the wall and the soil and/or rock, wraps around the force distribution members 44 , 46 , and then extends back underneath the upper adjacent block 14 (into the wall), into the lock channel 24 of the upper adjacent block, and back to the exterior surface of the wall 18 , tracing a substantially C-shaped path.
In the wall system illustrated in FIG. 4, the reinforcement member 60 is locked to the wall 10 with a pair of retaining bars 64 that are positioned in the two lock channels 24 adjacent the tieback rod 38 . These retaining bars 64 lie atop the reinforcement member 60 and holds it against the rear walls of the locking channels 24 to prevent the reinforcement member from being pulled out from the retaining wall 10 . Although such retaining means are preferred, it will be understood that other types of retaining means could be used. When a tensile force is applied to the tieback rod 38 and translated to the reinforcement member 60 , the retaining bars 64 are urged towards the rear wall of the channels 24 , locking the reinforcement member in place. Thus, like the system of the first embodiment, the anchoring system of the second embodiment similarly distributes the forces exerted by the soil and/or rock of the embankment throughout the retaining wall 10 .
While preferred embodiments of the invention have been disclosed in detail in the foregoing description and drawings, it will be understood by those skilled in the art that variations and modifications thereof can be made without departing from the spirit and scope of the invention. For instance, although the anchoring system of the first embodiment herein is described and shown in use with a retaining wall having horizontal inner passageways, it is to be appreciated that this systems easily could be adapted for use with a retaining wall having vertical inner passageways. | A retaining wall anchoring system for a segmental retaining wall comprising a plurality of tieback rods adapted to be embedded into soil or rock with a proximal portion extending therefrom, at least one elongated force distribution member positionable directly adjacent the proximal portion of at least one of the tieback rods, a washer positionable about the proximal portions of the tieback rod in abutment with the force distribution member, and a fastener fixedly securable to the proximal portion of the tieback rod to securely clamp the washer against the force distribution member such that tensile forces imposed on the tieback rod are transmitted to the force distribution member so as to distribute these forces throughout a portion of the retaining wall. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. patent application Ser. No. 11/533,679, filed on Sep. 20, 2006, which is a divisional of U.S. patent application Ser. No. 11/101,855, filed on Apr. 8, 2005, now issued as U.S. Pat. No. 7,124,831, which is a continuation of U.S. patent application Ser. No. 10/811,559, filed on Mar. 29, 2004, now abandoned, which is a continuation of U.S. patent application Ser. No. 09/893,505, filed on Jun. 27, 2001, now issued as U.S. Pat. No. 6,712,153, which are each incorporated by reference herein in their entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a downhole non-metallic sealing element system. More particularly, the present invention relates to downhole tools such as bridge plugs, frac-plugs, and packers having a non-metallic sealing element system.
2. Background of the Related Art
An oil or gas well includes a wellbore extending into a well to some depth below the surface. Typically, the wellbore is lined with tubulars or casing to strengthen the walls of the borehole. To further strengthen the walls of the borehole, the annular area formed between the casing and the borehole is typically filled with cement to permanently set the casing in the wellbore. The casing is then perforated to allow production fluid to enter the wellbore and be retrieved at the surface of the well.
Downhole tools with sealing elements are placed within the wellbore to isolate the production fluid or to manage production fluid flow through the well. The tools, such as plugs or packers for example, are usually constructed of cast iron, aluminum, or other alloyed metals, but have a malleable, synthetic element system. An element system is typically made of a composite or synthetic rubber material which seals off an annulus within the wellbore to prevent the passage of fluids. The element system is compressed, thereby expanding radially outward from the tool to sealingly engage a surrounding tubular. For example, a bridge plug or frac-plug is placed within the wellbore to isolate upper and lower sections of production zones. By creating a pressure seal in the wellbore, bridge plugs and frac-plugs allow pressurized fluids or solids to treat an isolated formation.
FIG. 1 is a cross sectional view of a conventional bridge plug 50 . The bridge plug 50 generally includes a metallic body 80 , a synthetic sealing member 52 to seal an annular area between the bridge plug 50 and an inner wall of casing there-around (not shown), and one or more metallic slips 56 , 61 . The sealing member 52 is disposed between an upper metallic retaining portion 55 and a lower metallic retaining portion 60 . In operation, axial forces are applied to the slip 56 while the body 80 and slip 61 are held in a fixed position. As the slip 56 moves down in relation to the body 80 and slip 61 , the sealing member is actuated and the slips 56 , 61 are driven up cones 55 , 60 . The movement of the cones and slips axially compress and radially expand the sealing member 52 thereby forcing the sealing portion radially outward from the plug to contact the inner surface of the well bore casing. In this manner, the compressed sealing member 52 provides a fluid seal to prevent movement of fluids across the bridge plug 50 .
Like the bridge plug described above, conventional packers typically comprise a synthetic sealing element located between upper and lower metallic retaining rings. Packers are typically used to seal an annular area formed between two co-axially disposed tubulars within a wellbore. For example, packers may seal an annulus formed between production tubing disposed within wellbore casing. Alternatively, packers may seal an annulus between the outside of a tubular and an unlined borehole. Routine uses of packers include the protection of casing from pressure, both well and stimulation pressures, as well as the protection of the wellbore casing from corrosive fluids. Other common uses include the isolation of formations or leaks within a wellbore casing or multiple producing zones, thereby preventing the migration of fluid between zones. Packers may also be used to hold kill fluids or treating fluids within the casing annulus.
One problem associated with conventional element systems of downhole tools arises in high temperature and/or high pressure applications. High temperatures are generally defined as downhole temperatures above 200° F. and up to 450° F. High pressures are generally defined as downhole pressures above 7,500 psi and up to 15,000 psi. Another problem with conventional element systems occurs in both high and low pH environments. Low pH is generally defined as less than 6.0, and high pH is generally defined as more than 8.0. In these extreme downhole conditions, conventional sealing elements become ineffective. Most often, the physical properties of the sealing element suffer from degradation due to extreme downhole conditions. For example, the sealing element may melt, solidify, or otherwise loose elasticity.
Yet another problem associated with conventional element systems of downhole tools arises when the tool is no longer needed to seal an annulus and must be removed from the wellbore. For example, plugs and packers are sometimes intended to be temporary and must be removed to access the wellbore. Rather than de-actuate the tool and bring it to the surface of the well, the tool is typically destroyed with a rotating milling or drilling device. As the mill contacts the tool, the tool is “drilled up” or reduced to small pieces that are either washed out of the wellbore or simply left at the bottom of the wellbore. The more metal parts making up the tool, the longer the milling operation takes. Metallic components also typically require numerous trips in and out of the wellbore to replace worn out mills or drill bits.
There is a need, therefore, for a non-metallic element system that will effectively seal an annulus at high temperatures and withstand high pressure differentials without experiencing physical degradation. There is also a need for a downhole tool made substantially of a non-metallic material that is easier and faster to mill.
SUMMARY OF THE INVENTION
A non-metallic element system is provided which can effectively seal or pack-off an annulus under elevated temperatures. The element system can also resist high differential pressures as well as high and low pH environments without sacrificing performance or suffering mechanical degradation. Further, the non-metallic element system will drill up considerably faster than a conventional element system that contains metal.
The element system comprises a non-metallic, composite material that can withstand high temperatures and high pressure differentials. In one aspect, the composite material comprises an epoxy blend reinforced with glass fibers stacked layer upon layer at about 30 to about 70 degrees.
A downhole tool, such as a bridge plug, frac-plug, or packer, is also provided that comprises in substantial part a non-metallic, composite material which is easier and faster to mill than a conventional bridge plug containing metallic parts. In one aspect, the tool comprises one or more support rings having one or more wedges, one or more expansion rings and a sealing member disposed in a functional relationship with the one or more expansion rings This assemblage of components is referred to herein as “an element system.”
In another aspect, a non-metallic mandrel for the downhole tool is formed of a polymeric composite material reinforced by fibers in layers angled at about 30 to about 70 degrees relative to an axis of the mandrel. Methods are provided for the manufacture and assembly of the tool and the mandrel, as well as for sealing an annulus in a wellbore using a downhole tool that includes a non-metallic mandrel and an element system.
BRIEF DESCRIPTION OF DRAWINGS
So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is a partial section view of a conventional bridge plug.
FIG. 2 is a partial section view of a non-metallic sealing system of the present invention.
FIG. 3 is an enlarged isometric view of a support ring of the non-metallic sealing system.
FIG. 4 is a cross sectional view along lines A-A of FIG. 2 .
FIG. 5 is partial section view of a frac-plug having a non-metallic sealing system of the present invention in a run-in position.
FIG. 6 is section view of a frac-plug having a non-metallic sealing system of the present invention in a set position within a wellbore.
FIG. 6A is an enlarged view of a non-metallic sealing system activated within a wellbore.
FIG. 7 is a cross sectional view along lines B-B of FIG. 6 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A non-metallic element system that is capable of sealing an annulus in very high or low pH environments as well as at elevated temperatures and high pressure differentials is provided. The non-metallic element system is made of a fiber reinforced polymer composite that is compressible and expandable or otherwise malleable to create a permanent set position.
The composite material is constructed of a polymeric composite that is reinforced by a continuous fiber such as glass, carbon, or aramid, for example. The individual fibers are typically layered parallel to each other, and wound layer upon layer. However, each individual layer is wound at an angle of about 30 to about 70 degrees to provide additional strength and stiffness to the composite material in high temperature and pressure downhole conditions. The tool mandrel is preferably wound at an angle of 30 to 55 degrees, and the other tool components are preferably wound at angles between about 40 and about 70 degrees. The difference in the winding phase is dependent on the required strength and rigidity of the overall composite material.
The polymeric composite is preferably an epoxy blend. However, the polymeric composite may also consist of polyurethanes or phenolics, for example. In one aspect, the polymeric composite is a blend of two or more epoxy resins. Preferably, the composite is a blend of a first epoxy resin of bisphenol A and epichlorohydrin and a second cycoaliphatic epoxy resin. Preferably, the cycloaphatic epoxy resin is Araldite® liquid epoxy resin, commercially available from Ciga-Geigy Corporation of Brewster, N.Y. A 50:50 blend by weight of the two resins has been found to provide the required stability and strength for use in high temperature and pressure applications. The 50:50 epoxy blend also provides good resistance in both high and low pH environments.
The fiber is typically wet wound, however, a prepreg roving can also be used to form a matrix. A post cure process is preferable to achieve greater strength of the material. Typically, the post cure process is a two stage cure consisting of a gel period and a cross linking period using an anhydride hardener, as is commonly know in the art. Heat is added during the curing process to provide the appropriate reaction energy which drives the cross-linking of the matrix to completion. The composite may also be exposed to ultraviolet light or a high-intensity electron beam to provide the reaction energy to cure the composite material.
FIG. 2 is a partial cross section of a non-metallic element system 200 made of the composite, filament wound material described above. The element system 200 includes a sealing member 210 , a first and second cone 220 , 225 , a first and second expansion ring 230 , 235 , and a first and second support ring 240 , 245 disposed about a body 250 . The sealing member 210 is backed by the cones 220 , 225 . The expansion rings 230 , 235 are disposed about the body 250 between the cones 220 , 225 , and the support rings 240 , 245 , as shown in FIG. 2 .
FIG. 3 is an isometric view of the support ring 240 , 245 . As shown, the support ring 240 , 245 is an annular member having a first section 242 of a first diameter that steps up to a second section 244 of a second diameter. An interface or shoulder 246 is therefore formed between the two sections 242 , 244 . Equally spaced longitudinal cuts 247 are fabricated in the second section to create one or more fingers or wedges 248 there-between. The number of cuts 247 is determined by the size of the annulus to be sealed and the forces exerted on the support ring 240 , 245 .
Still referring to FIG. 3 , the wedges 248 are angled outwardly from a center line or axis of the support ring 240 , 245 at about 10 degrees to about 30 degrees. As will be explained below in more detail, the angled wedges 248 hinge radially outward as the support ring 240 , 245 moves axially across the outer surface of the expansion ring 230 , 235 . The wedges 248 then break or separate from the first section 242 , and are extended radially to contact an inner diameter of the surrounding tubular (not shown). This radial extension allows the entire outer surface area of the wedges 248 to contact the inner wall of the surrounding tubular. Therefore, a greater amount of frictional force is generated against the surrounding tubular. The extended wedges 248 thus generate a “brake” that prevents slippage of the element system 200 relative to the surrounding tubular.
Referring again to FIG. 2 , the expansion ring 230 , 235 may be manufactured from any flexible plastic, elastomeric, or resin material which flows at a predetermined temperature, such as Teflon® for example. The second section 244 of the support ring 240 , 245 is disposed about a first section of the expansion ring 230 , 235 . The first section of the expansion ring 230 , 235 is tapered corresponding to a complementary angle of the wedges 248 . A second section of the expansion ring 230 , 235 is also tapered to complement a sloped surface of the cone 220 , 225 . At high temperatures, the expansion ring 230 , 235 expands radially outward from the body 250 and flows across the outer surface of the body 250 . As will be explained below, the expansion ring 230 , 235 fills the voids created between the cuts 247 of the support ring 240 , 245 , thereby providing an effective seal.
The cone 220 , 225 is an annular member disposed about the body 250 adjacent each end of the sealing member 210 . The cone 220 , 225 has a tapered first section and a substantially flat second section. The second section of the cone 220 , 225 abuts the substantially flat end of the sealing member 210 . As will be explained in more detail below, the tapered first section urges the expansion ring 230 , 235 radially outward from the body 250 as the element system 200 is activated. As the expansion ring 230 , 235 progresses across the tapered first section and expands under high temperature and/or pressure conditions, the expansion ring 230 , 235 creates a collapse load on the cone 220 , 225 . This collapse load holds the cone 220 , 225 firmly against the body 250 and prevents axial slippage of the element system 200 components once the element system 200 has been activated in the wellbore. The collapse load also prevents the cones 220 , 225 and sealing member 210 from rotating during a subsequent mill up operation.
The sealing member 210 may have any number of configurations to effectively seal an annulus within the wellbore. For example, the sealing member 210 may include grooves, ridges, indentations, or protrusions designed to allow the sealing member 210 to conform to variations in the shape of the interior of a surrounding tubular (not shown). The sealing member 210 , however, should be capable of withstanding temperatures up to 450° F., and pressure differentials up to 15,000 psi.
In operation, opposing forces are exerted on the element system 200 which causes the malleable outer portions of the body 250 to compress and radially expand toward a surrounding tubular. A force in a first direction is exerted against a first surface of the support ring 240 . A force in a second direction is exerted against a first surface of the support ring 245 . The opposing forces cause the support rings 240 , 245 to move across the tapered first section of the expansion rings 230 , 235 . The first section of the support rings 240 , 245 expands radially from the mandrel 250 while the wedges 248 hinge radially toward the surrounding tubular. At a predetermined force, the wedges 248 will break away or separate from the first section 242 of the support rings 240 , 245 . The wedges 248 then extend radially outward to engage the surrounding tubular. The compressive force causes the expansion rings 230 , 235 to flow and expand as they are forced across the tapered section of the cones 220 , 225 . As the expansion rings 230 , 235 flow and expand, they fill the gaps or voids between the wedges 248 of the support rings 240 , 245 . The expansion of the expansion rings 230 , 235 also applies a collapse load through the cones 220 , 225 on the body 250 , which helps prevent slippage of the element system 200 once activated. The collapse load also prevents the cones 220 , 225 and sealing member 210 from rotating during the mill up operation which significantly reduces the required time to complete the mill up operation. The cones 220 , 225 then transfer the axial force to the sealing member 210 to compress and expand the sealing member 210 radially. The expanded sealing member 210 effectively seals or packs off an annulus formed between the body 250 and an inner diameter of a surrounding tubular.
The non-metallic element system 200 can be used on either a metal or more preferably, a non-metallic mandrel. The non-metallic element system 200 may also be used with a hollow or solid mandrel. For example, the non-metallic element system 200 can be used with a bridge plug or frac-plug to seal off a wellbore or the element system may be used with a packer to pack-off an annulus between two tubulars disposed in a wellbore. For simplicity and ease of description however, the non-metallic element system will now be described in reference to a frac-plug for sealing off a well bore.
FIG. 5 is a partial cross section of a frac-plug 300 having the non-metallic element system 200 described above. In addition to the non-metallic element system 200 , the frac-plug 300 includes a mandrel 301 , slips 310 , 315 , and cones 320 , 325 . The non-metallic element system 200 is disposed about the mandrel 301 between the cones 320 , 325 . The mandrel 301 is a tubular member having a ball 309 disposed therein to act as a check valve by allowing flow through the mandrel 301 in only a single axial direction.
The slips 310 , 315 are disposed about the mandrel 302 adjacent a first end of the cones 320 , 325 . Each slip 310 , 315 comprises a tapered inner surface conforming to the first end of the cone 320 , 325 . An outer surface of the slip 310 , 315 , preferably includes at least one outwardly extending serration or edged tooth, to engage an inner surface of a surrounding tubular (not shown) when the slip 310 , 315 is driven radially outward from the mandrel 301 due to the axial movement across the first end of the cones 320 , 325 thereunder.
The slip 310 , 315 is designed to fracture with radial stress. The slip 310 , 315 typically includes at least one recessed groove (not shown) milled therein to fracture under stress allowing the slip 310 , 315 to expand outwards to engage an inner surface of the surrounding tubular. For example, the slip 310 , 315 may include four sloped segments separated by equally spaced recessed grooves to contact the surrounding tubular, which become evenly distributed about the outer surface of the mandrel 301 .
The cone 320 , 325 is disposed about the mandrel 301 adjacent the non-metallic sealing system 200 and is secured to the mandrel 301 by a plurality of shearable members 330 such as screws or pins. The shearable members 330 may be fabricated from the same composite material as the non-metallic sealing system 200 , or the shearable members may be of a different kind of composite material or metal. The cone 320 , 325 has an undercut 322 machined in an inner surface thereof so that the cone 320 , 325 can be disposed about the first section 242 of the support ring 240 , 245 , and butt against the shoulder 246 of the support ring 240 , 245 .
As stated above, the cones 320 , 325 comprise a tapered first end which rests underneath the tapered inner surface of the slips 310 , 315 . The slips 310 , 315 travel about the tapered first end of the cones 320 , 325 , thereby expanding radially outward from the mandrel 301 to engage the inner surface of the surrounding tubular.
A setting ring 340 is disposed about the mandrel 301 adjacent a first end of the slip 310 . The setting ring 340 is an annular member having a first end that is a substantially flat surface. The first end serves as a shoulder which abuts a setting tool described below.
A support ring 350 is disposed about the mandrel 301 adjacent a first end of the setting ring 340 . A plurality of pins 345 secure the support ring 350 to the mandrel 301 . The support ring 350 is an annular member and has a smaller outer diameter than the setting ring 340 . The smaller outer diameter allows the support ring 350 to fit within the inner diameter of a setting tool so the setting tool can be mounted against the first end of the setting ring 340 .
The frac-plug 300 may be installed in a wellbore with some non-rigid system, such as electric wireline or coiled tubing. A setting tool, such as a Baker E-4 Wireline Setting Assembly commercially available from Baker Hughes, Inc., for example, connects to an upper portion of the mandrel 301 . Specifically, an outer movable portion of the setting tool is disposed about the outer diameter of the support ring 350 , abutting the first end of the setting ring 340 . An inner portion of the setting tool is fastened about the outer diameter of the support ring 350 . The setting tool and frac-plug 300 are then run into the well casing to the desired depth where the frac-plug 300 is to be installed.
To set or activate the frac-plug 300 , the mandrel 301 is held by the wireline, through the inner portion of the setting tool, as an axial force is applied through the outer movable portion of the setting tool to the setting ring 340 . The axial forces cause the outer portions of the frac-plug 300 to move axially relative to the mandrel 301 . FIGS. 6 and 6A show a section view of a frac-plug having a non-metallic sealing system of the present invention in a set position within a wellbore.
Referring to both FIGS. 6 and 6A , the force asserted against the setting ring 340 transmits force to the slips 310 , 315 and cones 320 , 325 . The slips 310 , 315 move up and across the tapered surface of the cones 320 , 325 and contact an inner surface of a surrounding tubular 700 . The axial and radial forces applied to slips 310 , 315 causes the recessed grooves to fracture into equal segments, permitting the serrations or teeth of the slips 310 , 315 to firmly engage the inner surface of the surrounding tubular.
Axial movement of the cones 320 , 325 transfers force to the support rings 240 , 245 . As explained above, the opposing forces cause the support rings 240 , 245 to move across the tapered first section of the expansion rings 230 , 235 . As the support rings 240 , 245 move axially, the first section of the support rings 240 , 245 expands radially from the mandrel 250 while the wedges 248 hinge radially toward the surrounding tubular. At a pre-determined force, the wedges 248 break away or separate from the first section 242 of the support rings 240 , 245 . The wedges 248 then extend radially outward to engage the surrounding tubular 700 . The compressive force causes the expansion rings 230 , 235 to flow and expand as they are forced across the tapered section of the cones 220 , 225 . As the expansion rings 230 , 235 flow and expand, the rings 230 , 235 fill the gaps or voids between the wedges 248 of the support rings 240 , 245 , as shown in FIG. 7 . FIG. 7 is a cross sectional view along lines B-B of FIG. 6 .
Referring again to FIGS. 6 and 6A , the growth of the expansion rings 230 , 235 applies a collapse load through the cones 220 , 225 on the mandrel 301 , which helps prevent slippage of the element system 200 once activated. The cones 220 , 225 then transfer the axial force to the sealing member 210 which is compressed and expanded radially to seal an annulus formed between the mandrel 301 and an inner diameter of the surrounding tubular 700 .
In addition to frac-plugs as described above, the non-metallic element system 200 described herein may also be used in conjunction with any other downhole tool used for sealing an annulus within a wellbore, such as bridge plugs or packers, for example. Moreover, while foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | A non-metallic element system is provided as part of a downhole tool that can effectively seal or pack-off an annulus under elevated temperatures. The element system can also resist high differential pressures without sacrificing performance or suffering mechanical degradation, and is considerably faster to drill-up than a conventional element system. In one aspect, the composite material comprises an epoxy blend reinforced with glass fibers stacked layer upon layer at about 30 to about 70 degrees. In another aspect, a mandrel is formed of a non-metallic polymeric composite material. A downhole tool, such as a bridge plug, frac-plug, or packer, is also provided. The tool comprises a support ring having one or more wedges, an expansion ring, and a sealing member positioned with the expansion ring. | 4 |
This application claims the benefit of prior provisional application, Provisional Application Ser. No. 60/108,087, filed Nov. 12, 1998.
TECHNICAL FIELD
This invention relates to surgical reattachment of soft tissue/ligament to bone, and more particularly, instrumentation for surgically securing an allograft or prosthetic ligament into a patient's bone as part of a procedure to replace cruciate ligaments.
BACKGROUND
Surgical re-attachment of soft tissue to bone due to traumatic injury or surgical procedures has created a need for efficient and time-saving instruments, implants, and procedures. Current methods of re-attachment of soft tissue to bone include bone tunnels, surgical staples, surgical tacks, interference screws, and bone anchors. If the desired result is solely approximation of the soft tissue back to the bony insertion site, the aforementioned devices can be used within certain limitations. There are, however, certain tendons and ligaments, which present the surgeon with a very specific set of constraints, for example, grafting of a tendon into the site of an irreparably torn anterior cruciate ligament in the human knee.
Each repair technique has a unique set of constraints. For instance, interference screws are difficult to insert and can damage a graft on insertion. In order to insert an interference screw, a large hole must be drilled to accommodate the graft and the screw. The screw prevents bone to tendon fixation around the screw, can leave a weak defect in the bone, and can vascularize the area under compression. In another instance, bone tunnels require additional incisions and trauma to the patient. With a bone tunnel, there is little radial compression on the graft to the bone site and the securing suture may creep or be cut by the bone, and the securing knot may slip. With surgical staples, again additional incisions and trauma to the patient occurs, and there is little radial compression on the graft to the bone site. The surgical staple may even not stay in the bone. In another example, using a device having an internal screw in a tunnel and a ratcheting inner element that presses into the outer screw in anterior cruciate ligament (ACL) repair does not provide radial compression for graft healing. Also, such a device is difficult to revise.
SUMMARY
A system of instrumentation and implants for surgically securing an allograft or prosthetic ligament into a patient's bone is used in a procedure to replace a patient's cruciate ligaments. In one general aspect, a fixation device for attaching soft tissue to bone includes a fixation mechanism, a shaft, and a securing mechanism, which slides along the shaft. The securing mechanism may include an internal one-way locking mechanism.
In another aspect, a device for attaching soft tissue to bone includes a shaft, a fixation mechanism attached to the shaft, a one-way track for inserting the shaft therein and the fixation mechanism therethrough; and a securing mechanism for holding a graft within the one-way track by compressing the securing mechanism against the graft. The securing mechanism may be at least one of a conical shape, a cylindrical shape, a cubic shape, or a complex shape capable of exerting an adequate radial force against the graft and into a surrounding bone. The fixation device may include a fixation mechanism with an expansion leg, a shaft with a one-way track, and a securing mechanism. The expansion leg of the fixation mechanism may be single or multiple legs or may be toggles, legs, expansion arms, barbs, tines, or other apparatuses to prevent backward translation. The one-way track of the shaft may be a single length or multiple lengths, i.e., an adjustable length member. The securing mechanism holds the tissue and has an internal one-way lock, which slides along the one-way track. Alternatively, the fixation mechanism may include an inner core that expands as a result of the insertion of a device that causes radial displacement, for example, a wedge, a tapered plug, or a screw.
A fixation device may be made of any biocompatible metal, such as titanium or stainless steel, plastic, such as nylon or polyester, or bioabsorbable, such as PLLA. Any material suitable for use in the body can be used. The material must provide adequate resistance to creep, hold the load required, and not be affected by cyclic loading.
The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a representation of a human knee with an ACL graft held in place, generally in accordance with the fixation device.
FIGS. 2A-2T are examples of various fixation mechanisms.
FIGS. 3A-3D are various views of the fixation mechanism shown in FIG. 2 A.
FIGS. 4A-4D are various views of the fixation mechanism shown in FIG. 2 B.
FIG. 5 depicts the fixation mechanism shown in FIG. 2E disposed on a shaft.
FIGS. 6A-6D are various views of a securing mechanism.
FIG. 7 schematically depicts the shaft and the securing mechanism disposed together.
Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
FIG. 1 is a representation of a human knee with an ACL graft 100 (three lines) held in place the joint space between the tibia 90 and the femur 20 by a fixation device. The fixation device includes two fixation mechanisms 110 , 140 and two securing mechanisms 120 , 130 . Each fixation mechanism 110 , 140 has a locking strip (not shown) and is connected to its respective securing mechanism 120 , 130 by a one-way locking mechanism (not shown).
FIGS. 2A-2T are examples of various fixation mechanisms. The fixation mechanism provides resistance to the tensile forces, which are exerted on the graft site. Generally, the length of the fixation mechanism is greater than its width. A fixation mechanism may include a toggle pin member or a toggle element, as shown, for example, in FIGS. 2A-2C. FIG. 2A is a simple toggle fixation mechanism 110 having a parallelogram shaped piece horizontal member 112 (as seen also in FIG. 1) attached to a longitudinal member 114 . The longitudinal member 114 , which is disposed in the insertion tunnel, may be attached to the horizontal member 112 by a pin or screw or the like 116 .
FIG. 2B is an alternative form of a simple toggle fixation mechanism 210 that has a rectangular shaped horizontal member 212 attached to a longitudinal member 214 by a pin or screw or the like 216 . The rectangular shaped horizontal member 212 has a plurality of teeth 218 disposed along one side.
FIG. 2C is a spring-loaded toggle fixation mechanism 220 that has a parallelogram-shaped horizontal member 222 attached to a longitudinal member 224 by a spring 226 .
FIG. 2D is a pull rod fixation mechanism 230 comprised of three longitudinal members 232 , 234 , 236 . Two of the three longitudinal members 232 , 236 have a duck-bill-like head portion 235 , 237 , which extends over the edge of the insertion tunnel to hold the fixation mechanism in place.
FIG. 2E is a self-spring flyout fixation mechanism 240 comprised of two longitudinal members 245 connected together at their base 242 . Each longitudinal member 245 has a duck-bill-like head portion 246 , which extends over the edge of the insertion tunnel to hold the fixation mechanism in place.
FIG. 2F is a spring-loaded butterfly fixation mechanism 250 that has a longitudinal member 252 and a butterfly-shaped horizontal member 254 comprised of two arms 256 . The arms 256 of the butterfly-shaped horizontal member 254 are connected together and to longitudinal member 252 by a spring 258 .
FIG. 2G is a simple butterfly fixation mechanism 260 that has a longitudinal member 262 and a butterfly-shaped horizontal member 264 comprised of two arms 266 . The arms 266 of the butterfly-shaped horizontal member 264 are connected together and to the longitudinal member 262 by a pin or screw or the like 268 .
FIG. 2H is a duck-bill-shaped fixation mechanism 270 . As shown, the head of the fixation mechanism looks like a duck-bill 272 such that the bill portion extends over an edge of the insertion tunnel to hold the fixation mechanism in place.
FIG. 2I is a straight jam pin fixation mechanism 280 comprised of a first longitudinal member 282 and a second longitudinal member 284 with a horizontal portion 286 . The horizontal portion 286 extends over an edge of the insertion tunnel to hold the fixation mechanism in place. FIG. 2J is a tapered jam pin fixation mechanism 290 similar to the straight jam pin of FIG. 2 I. However, the interior contacting sides 293 , 295 of the first longitudinal member 292 and the longitudinal portion of the second longitudinal member 294 are reciprocally tapered.
FIG. 2K is a push rod fixation mechanism 300 comprising three longitudinal members 302 , 304 , 306 . The two outer longitudinal members 302 , 306 have respective horizontal portions 303 , 307 that extend over the edges of the insertion tunnel to hold the fixation mechanism in place. The interior longitudinal member 304 is shaped like a blunt pen tip. The respective longitudinal portions 308 , 309 of the outer longitudinal members 302 , 306 are shaped around the blunt pen tip shape of the interior longitudinal member 304 .
FIG. 2L is a fixation mechanism 310 formed of guided flexible rods 312 , 314 . The rods 312 , 314 each have a horizontal portion 313 , 315 , which extend over the edges of the insertion tunnel to hold the fixation mechanism in place.
FIG. 2M is a swinging cam fixation mechanism 320 with three circular members 322 , 324 , 326 , two horizontal members 327 , 328 , and a block-shaped member 321 , which is disposed in the insertion tunnel.
FIG. 2N is a fixation mechanism 330 that includes spring loaded pins 332 , 334 disposed on a longitudinal member 336 . FIG. 20 is a fixation mechanism 340 that has a single spring-loaded pin 342 disposed on a longitudinal member 344 . FIG. 2P is a fixation mechanism 350 that includes rotary flyouts 352 .
FIG. 2Q is a fixation mechanism 360 with a pop rivet 362 disposed on the longitudinal member 364 . FIG. 2R is a one-piece butterfly 370 having a longitudinal member 372 disposed in the insertion tunnel and two arms 374 , 376 that extend over the respective edge of the insertion tunnel.
FIG. 2S is a threaded push rod fixation mechanism 380 similar in shape and form to the push rod fixation mechanism shown in FIG. 2 K. However, threaded push rod fixation mechanism 380 has thread portions 388 , 389 on the respective interior, contacting portions of outer longitudinal members 382 , 386 and interior longitudinal member 384 .
FIG. 2T is a threaded pull rod fixation mechanism 390 similar in shape and form to pull rod fixation mechanism 230 shown in FIG. 2 D. However, the respective interior contact points of longitudinal members 392 , 396 and interior longitudinal member 394 have threaded portions 398 , 399 .
FIGS. 3A-3D show various views of the simple toggle fixation mechanism 110 shown in FIG. 2 A. FIG. 3A is a side view of the parallelogram-shaped horizontal member 112 of the fixation mechanism. FIG. 3B is a top end view of the longitudinal member 114 of the fixation mechanism. FIG. 3C is a side elevated view of the parallelogram-shaped horizontal piece 112 of the fixation mechanism. FIG. 3D is a side view of the longitudinal member 114 of the fixation mechanism.
FIGS. 4A-4D show various views of the alternative simple toggle fixation mechanism 210 shown in FIG. 2 B. FIG. 4A is a side view of the longitudinal member 214 of the fixation mechanism. FIG. 4B is a side view of the horizontal member 212 of the fixation mechanism. FIG. 4C is an elevated side view of the horizontal member 212 of the fixation mechanism with the teeth 218 exposed. FIG. 4D is a top end view of the longitudinal member 214 of the fixation mechanism.
FIG. 5 depicts the fixation mechanism 240 shown in FIG. 2E disposed on a shaft 510 . The shaft 510 has a plurality of raised portions 520 disposed thereon. Referring back to FIG. 1, the shaft 510 is disposed within the insertion tunnel such that the fixation mechanism disposed thereon (in FIG. 1, fixation mechanism 110 ) protrudes from an end of the insertion tunnel. The shaft 510 , for instance, is a one-way track, which has, for example, pins, transverse tracks or bumps, intended to prevent a closely fit external sliding member, such as a securing mechanism, from reversing direction once it has started sliding on the shaft 510 .
FIGS. 6A-6D show various views of a securing mechanism 600 . Generally, a securing mechanism 600 has the shape of a plug with cutouts or channels 635 , designed to support tendon grafts without damage, about its circumference, i.e., a support plug. FIG. 6A is a longitudinal side view of the securing mechanism 600 . FIG. 6B is a schematic elevated perspective view of the securing mechanism 600 showing the cutouts 635 in the outer circumference of the securing mechanism 600 . FIG. 6C is a schematic end view of the securing mechanism 600 , showing the cutouts 635 . FIG. 6D is a horizontal side view of the securing mechanism 600 . The securing mechanism could be, for example, a cylindrical, a conical, a cubic, or a complex shape, which provides adequate radial force against the graft into the surrounding bone. The securing mechanism may be made of any biocompatible metal, polymer, bioabsorbable polymer, or bone. If bone is used, an additional securing mechanism must be used to provide the one-way locking on the shaft. The securing mechanism can transport site-specific drugs, such as bone morphing proteins, antibiotics, anti-inflammatories, and anesthetics.
FIG. 7 schematically depicts a fixation mechanism 240 on the shaft 510 and the securing mechanism 600 disposed together. The securing mechanism 600 is moved in the direction of the arrow along the shaft 510 , whereby the securing mechanism 600 engages with the shaft 510 to lock in place.
The system of instrumentation and devices for attaching soft tissue to bone reduces the operating room time required to perform a procedure. The fixation device can be used in confined spaces, such as those in and around the human knee. The fixation device for attaching soft tissue to bone can be made of bioabsorbable, biopolymer, or biometal and can be easily removed and replaced. The devices can be deployed with one hand and allow the surgeon to individually tension each leg of an ACL graft. Using the system and/or device does not damage ACL grafts and a variety of graft sizes can be accommodated. Both ends of an ACL graft can be inserted through a single incision. Once the graft is in place, the securing mechanism radially presses the graft against the side of the insertion tunnel, maintaining maximum graft to bone area required for optimal healing. There is high resistance to pull out as compared to standard interference screws that are approximately 800 N on the femoral side.
The system of instrumentation and devices for surgically securing an allograft or prosthetic ligament in a patient's bone are used in a procedure to replace a patient's cruciate ligaments. As part of the replacement procedure for the anterior cruciate ligament, the patient's leg is bent at an approximately ninety (90°) degree angle and a single incision is made medial to the tibial tuberosity. Through this incision, an insertion tunnel is created at the desired insertion point of the graft using standard orthopaedic techniques. The insertion tunnel exits on the lateral aspect of the femoral cortex. A replacement ligament is prepared using a hamstring allograft.
The fixation device is loaded with the graft at full-length extension. The fixation mechanism is pushed into the insertion tunnel until it exits the femoral insertion tunnel. The fixation device is pulled back to allow the fixation mechanism to rotate to prevent further retrograde movement, i.e., in FIG. 1, the horizontal portion of the fixation mechanism 110 , e.g., the toggle, rotates to a horizontal position across the femoral insertion tunnel. The shaft holds the fixation mechanism taut and the securing mechanism is slid forward into the insertion tunnel. Inside the securing mechanism is a one-way locking gate, which prevents retrograde movement of the securing mechanism along the shaft. The securing mechanism also presses the graft against the sidewall of the tunnel to facilitate healing over a larger area. The securing mechanism provides radial force to press the graft against the sidewall of the bone tunnel for faster and more efficient healing.
The graft is held in place within the femoral insertion tunnel by compression of the securing mechanism against the graft and is prevented from being pulled out of the insertion tunnel by the fixation mechanism. Once the femoral side of the graft is pressed in place and locked on the shaft, the tibial end of the graft is pulled into position and also locked into place.
An insertion instrument allows the surgeon to deploy the fixation device with one hand: position the fixation mechanism, push the securing mechanism, and cut off the excess length of the graft using one hand.
A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope. Accordingly, other implementations are within the scope of the following claims. | A system of instrumentation and implants for surgically securing an allograft or prosthetic ligament into a patient's bone is part of a procedure to replace cruciate ligaments. A fixation device for attaching soft tissue to bone includes a fixation mechanism, a shaft, and a securing mechanism. Alternatively, the fixation mechanism may include an expansion leg, the shaft may include a one-way track. In another implementation, the fixation mechanism may include an inner core that expands as a result of insertion of a device that causes radial displacement. | 0 |
BACKGROUND
[0001] Transistors are foundational devices of the semiconductor industry. One type of transistor, the field effect transistor (FET), has among its components gate, source, and drain terminals. A voltage applied between the gate and the source terminals generates an electric field that creates an “inversion channel” through which current can flow. Such current flow may be controlled by varying the magnitude of the applied voltage.
[0002] Many configurations and fabrication methods have been devised for transistor gate terminals (as well as for other transistor components). One such configuration is what is called a double gate transistor, in which a transistor has two gates instead of a single gate. Forming such a transistor can raise certain difficulties such as tip implants into a non-gated or channel region of the transistor, which can cause undesired off-state leakage.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is a plan view of a double gate transistor in accordance with an embodiment of the present invention.
[0004] FIGS. 2A and 2B are cross-section and top views of the embodiment of FIG. 1 .
[0005] FIG. 3 is a flow diagram of a method for forming self-aligned tip spacers in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
[0006] In various embodiments, self-aligned tip spacers may be provided in a multi-gate transistor structure to mask a portion of a silicon-on-insulator (SOI) structure. By masking off a part of the SOI structure, these spacers may act as masks to prevent implantation into the area under them, while the side surfaces of the SOI structure are implanted as needed. This is so, as diffusions that are performed to implant tip material can occur at an angle such as a 45° angle.
[0007] Referring now to FIG. 1 , shown is a plan view of a double gate transistor 10 in accordance with an embodiment of the present invention. As shown in FIG. 1 , transistor 10 includes a buried oxide layer (BOX) 20 . While not shown in FIG. 1 , it is to be understood that BOX 20 may be formed on a suitable substrate such as a silicon substrate. A silicon structure 30 , which may be a SOI layer that is patterned into a fin-type structure formed on BOX 20 . In turn, a front gate 40 a and a back gate 40 b , which may be formed of polysilicon may be deposited and patterned to form the front and back gates respectively. Front and back gates 40 a and 40 b may be separated by an insulator 50 which may be a nitride layer, for example. A high dielectric constant (high-K) material may be present at the interfaces between the sidewalls of SOI 30 and gates 40 a and 40 b , as the high-K insulator may be formed prior to gate polysilicon deposition. To mask off a portion of the top surface of SOI 30 , a localized spacer 55 may be formed, also of nitride, for example. While only shown on one side of transistor 10 , it is to be understood that a corresponding spacer may be formed on the other side of transistor 10 .
[0008] FIG. 2A shows a cross-section view along the line B-B′ of FIG. 1 and a top down view of the transistor structure, respectively. Specifically, as shown in FIG. 2A by presence of tip spacers 55 a and 55 b , after diffusion of implants zero or reduced diffusions are present in locations 35 immediately underneath spacers 55 a and 55 b . Instead, the implants are primarily provided in portions 30 a and 30 b , while pure silicon remains in SOI portion 30 . Similarly, from a top down view as shown in FIG. 2B spacers 55 a and 55 b abut insulator 50 to provide a mask over the underlying portions 35 of SOI 30 .
[0009] Referring now to FIG. 3 , shown is a flow diagram of a method in accordance with one embodiment of the present invention. As shown in FIG. 3 , method 100 may be used to form a double gate transistor in accordance with one embodiment. Method 100 may begin by patterning a stack structure that is formed of multiple layers including a SOI layer, an oxide layer, and a nitride layer (block 110 ). Specifically, trenches may be formed on either side of a stack by performing nitride and SOI dry etching. Thus a silicon fin may be formed over an underlying oxide layer, e.g., a BOX layer that is exposed on either side of the fin, with dielectric and insulation layers formed over the fin.
[0010] Referring still to FIG. 3 , then at block 120 a polysilicon layer may be deposited and then polished down to the level of the nitride layer. Note that polysilicon does not exist along the stack profile after the polishing step. The polysilicon may be used to form the double gates, i.e., on either side of the stack. Then at block 130 a hard mask layer may be deposited, which may be a nitride-based hard mask, in some embodiments.
[0011] Referring still to FIG. 4 at block 140 , the hard mask and underlying nitride layer may be selectively removed, e.g., via an etch process that will lead to localized tip spacers that extend from both sides of the insulation layers longitudinally. After the hard mask etch, the hard mask is completely etched away with most of the nitride layer underneath. At the same time, polysilicon, when exposed, is also eroded. Laterally, however, the hard mask etch can be designed to give a slight flare, and at the bottom of the hard mask flare the nitride layer is also tapered during the same etch process. Consequently, this flare is transferred to the underlying nitride layer. Note that the dual stack hard mask/nitride may be patterned with photoresist. Therefore, spacers will be formed at the nitride sidewalls due to this tapering. This taper is the main reason for the spacer to be created on top of the SOI during the subsequent processing steps.
[0012] The amount of nitride recessed laterally may be controlled during the final part of the etch sequence so as to not eliminate this spacer. In various embodiments, a predetermined control of radio frequency (RF) power and etch chemistry may be implemented. For example, in some embodiments a derivative of a conventional plasma etch may be used. Further, RF power may be modified. Specifically a power in the 500-1500 watts (W) range may change the extent of the spacer footing. Still further, pressures may be changed from approximately 100 to 200 milliTorrs (mT) to enable this flared shape rather than a vertical etch. Typical etch chemistries include methyl fluoride, carbon monoxide and oxygen (CH 3 F, CO and O 2 ). This subsequent nitride etch can also be carried out immediately post polysilicon etch, without inserting a break in the etch step (between poly and nitride etch). Various tool configurations such as electron cyclotron resonance (ECR) or inductively coupled plasma (ICP) sources can also be employed to etch the nitride on the SOI to create the final desired structure.
[0013] Referring still to FIG. 4 , another patterning process may be performed to remove polysilicon from the non-gate, i.e., the implantation regions, to thus expose the SOI fin (block 150 ). Specifically, a polysilicon etch may be followed by a slight nitride-clean dry etch step, such that the SOI is exposed, with no spacer along its sidewalls, while the self-aligned nitride spacer remains along the insulation layers' sidewalls. This patterning thus preserves the localized tip spacers. The top hard mask can then be stripped off to give the final structure.
[0014] This etching will enable diffusion of source and drain materials into the SOI fin. Furthermore, due to the self-aligned tip spacers, these tip implantations will not impinge into the channel region present under the stack. These self-aligned tip spacers may thus act as a mask on the top surface of the SOI fin extending from the insulation layer to protect a channel region present under the remaining insulation layer. Thus, diffusions may be performed to implant tips into the SOI fin (block 160 ). Further processing may be performed to form the source and drains, metallization contacts and so forth.
[0015] While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention. | In one embodiment, the present invention includes a double gate transistor having a silicon fin formed on a buried oxide layer and first and second insulation layers formed on a portion of the silicon fin, where at least the second insulation layer has a pair of portions extending onto respective first and second portions of the silicon fin to each act as a self-aligned spacer structure. Other embodiments are described and claimed. | 7 |
This application claims priority to U.S. provisional application No. 60/927,733 filed May 4, 2007 by Applicants, the entire content of which is hereby incorporated by reference.
FIELD
An embodiment of the device and method relates generally to the drilling industry. More particularly, an embodiment relates to a method and apparatus of a tubular breakout device having a support structure for maintaining the breakout device in a position, particularly a disengaged position.
BACKGROUND
In drilling, it is common practice to extend the length of the drill string by adding successive individual threaded sections of drill pipe to the top of the drill string. Each additional section of pipe is threaded to the preceding section. The rotation of the drill bit at the bottom of the drill string is accomplished by rotating the entire drill string. This rotation is induced by a drilling unit at the surface or top of the drill string, which rotates a quill. The quill is threaded to the last section of pipe in the drill string. This process continues until the drill string has reached the desired depth.
Once the drilling is completed and the pipe is to be removed from the drill string, the quill is operated in the reverse direction to unthread the individual pipe sections from the drill string. However, in the absence of external forces, it is unpredictable and difficult to control which of the threaded connections in the drill string will be broken first by this reverse rotation.
To avoid this problem, a drill unit is typically used which has a mechanism to move the quill along the machine at least the length of one section of the drill pipe. To unthread a section of drill pipe, the quill is first loosely threaded to the uppermost section of drill pipe. A breakout device, which coaxially surrounds the quill, is then manually lowered to simultaneously engage both the quill and the uppermost section of drill pipe in a manner which prevents the uppermost section of drill pipe and the quill from rotating in relation to each other. This is typically accomplished by providing a breakout device having one or more channels on its internal face which engage corresponding keys on both the quill and the drill pipe. In this manner, the threaded connection between the quill and the drill pipe is prevented from separating. The quill is then retracted so that the uppermost section of drill pipe is contained within the drill unit. The end of the next lower pipe is prevented from rotating. This may be accomplished by a slip and slip bowl assembly, wrench, tong wrench or any other method of locking the drill pipe in place. The quill is then rotated in the reverse or unthreading direction to break and completely separate the threaded connection between the two uppermost sections of drill pipe in the drill string. The single uppermost section of drill pipe is then swung away from the remainder of the drill string and the quill is lowered to allow a person to manually raise the breakout device from the engaged position to the disengaged position. The quill is then rotated in the reverse or unthreading direction, while a person holds the drill pipe in place, to separate the loosely threaded connection between the quill and the drill pipe. The quill is then loosely threaded to the next uppermost section of drill pipe in the drill string and the above process repeated until the entire drill string has been retracted.
The breakout device typically has two channels that run longitudinally along opposite sides of the inside face of the breakout device. These channels allow the breakout device to simultaneously engage keys located on opposite sides of both the quill and the drill pipe when the breakout device is in the engaged position. In the disengaged position, the breakout device is moved away from the drill pipe so that the breakout device is no longer engaged with the key of the drill pipe.
The breakout device is typically held in the raised or disengaged position by a chain connected to the quill on its upper end and the breakout device on its lower end. The lower end of the chain is connected to the breakout device in a manner which allows the chain and breakout device to be disconnected from each other. Typically this is achieved by attaching a hook to the breakout device which is suited to interlock with a link in the chain. To lower the breakout device from the disengaged to the engaged position, the chain is disconnected from the hook and the breakout device is lowered over the drill pipe so that the channels of the breakout device engage the key of the drill pipe.
The hook and chain assembly used to hold the breakout device in the disengaged position presents a significant safety hazard. When the drilling unit is in operation, the hook and chain rotate with the quill and breakout device regardless of whether the breakout device is in the engaged or disengaged position. While rotating, the hook and chain may contact the drilling unit operator, or any other person, causing injury to that person. There are other disadvantages of the hook and chain assembly that will be understood by those skilled in the art.
SUMMARY
An embodiment of the present device and method provides a device and method to support a breakout device in a position. In accordance with an embodiment, the breakout device has a cylindrical, hollow collar within which is formed a socket positioned adjacent to a channel, which is also formed within the collar. The socket is capable of receiving a key.
In another embodiment, the breakout device comprises a first channel in the inside face of the breakout device for receiving a corresponding key on a quill, a socket adjacent to the first channel, and a second channel parallel or substantially parallel to the first channel. The breakout device is moved from an engaged position to a disengaged and supported position by the method of moving the breakout device from an engaged position to a disengaged position, rotating the breakout device so that a key on a quill slides into the socket of the breakout device, then moved into a secured position by lowering the breakout device so that the key on the quill slides into a second channel of the breakout device. This allows the breakout device to be supported and locked in a disengaged position using the preexisting key of the quill. In an embodiment, the entire structure for supporting the breakout device in the disengaged position is contained within the breakout device itself. The second channel is considered to be substantially parallel to the first channel if a key on the quill is able to move from the first channel, through the socket, and into the second channel. The breakout device and other related parts may be constructed of any suitably strong material. The breakout device may be metal, such as steel, aluminum or aluminum alloys, a composite material, or any other suitable material. In an embodiment, the breakout device may be moved by any manual or powered means.
An embodiment of the breakout device may include a ring on the upper end of the breakout device. The ring provides a cap, barrier or end to the first channel of the breakout device. This prevents the key on the quill from exiting the first channel of the breakout device when the breakout device is lowered into the engaged position. This ring may be semipermanently attached to the upper end of the breakout device by screws, bolts, clamps, or any other method of attachment. Maintenance, replacement or access to the keys on the quill may be accomplished by detaching the ring and lowering the breakout collar to expose the keys of the quill. The ring may be made of metal, such as steel, aluminum or aluminum alloys, a composite material, or any other suitable material.
An embodiment of the breakout device may also have contact points on the bottom end of the internal face of the breakout device that engage the key of the drill pipe. These contact points may be replaceable in a manner which allows new contact points to be attached to the breakout device when the original contact points become worn from use. These replaceable contact points may be attached by welding, bolting or screwing the contact points to the breakout device. Any other suitable method for attaching the contact points to the breakout device may be used. These contact points may be made of metal, such as steel, aluminum or aluminum alloys, a composite material, or any other suitable material.
An embodiment of the breakout device may also include additional structures such as a flange on the breakout device. One possible function of such a flange is to provide an abutment surface for an operator to grasp or place his or her hand against to aid in manually raising the breakout device to the disengaged position.
In accordance with an alternative embodiment, the breakout device has a key capable of mating with a channel located in a quill. The quill has a socket adjacent to the channel that is capable of receiving a key. All other modifications described above for any embodiment may also be applied to this or other alternative embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a first embodiment depicting a quill, breakout collar, and drill pipe. The breakout collar is shown in partial cutaway.
FIG. 2 is a perspective view of a first embodiment depicting a quill connected to a section of drill pipe, and a breakout collar in the engaged position. The breakout collar is shown in partial cutaway.
FIG. 3 is a perspective view of a first embodiment depicting a quill and a breakout collar in the disengaged position. The breakout collar is shown in partial cutaway.
FIG. 4 is an elevation view of a first embodiment depicting a breakout collar.
FIG. 5 is a plan view of a first embodiment depicting a breakout collar.
FIG. 6 is a bottom view of a first embodiment depicting a breakout collar.
FIG. 7 is a sectional view taken along the line 7 - 7 in FIG. 5 .
FIG. 8 is a sectional view taken along the line 8 - 8 in FIG. 5 .
FIG. 9 is an exploded perspective view of an alternative embodiment depicting a quill, breakout collar, and drill pipe. The breakout collar is shown in partial cutaway.
FIG. 10 is an exploded perspective view of a second alternative embodiment depicting a quill, breakout collar, and drill pipe. The breakout collar is shown in partial cutaway.
DETAILED DESCRIPTION
Referring now to the drawings, there is shown a breakout assembly ( 10 ) with a breakout collar ( 20 ) having a support structure for maintaining the breakout device in a position, particularly a disengaged position. Referring more particularly to FIG. 1 , there is shown an exploded perspective view of a breakout collar ( 20 ), a lower section of a quill ( 40 ), and an upper section of a drill pipe ( 50 ). The breakout collar ( 20 ) has an external face ( 22 ) and an internal face ( 24 ). The breakout collar has first channels ( 26 ) formed into the internal face of the breakout collar. The first channels are of a size and shape which allows the channel to mate with keys ( 48 ) located on the quill ( 40 ). The first channels ( 26 ) extend longitudinally along the internal face ( 24 ) of the breakout collar. The first channels may be of any length sufficient to allow for the vertical movement of the keys ( 48 ) within the first channels. This first channels will allow the breakout collar to be raised and lowered relative to the quill with the keys traveling within the first channels. In an embodiment, the breakout collar is located around the quill by raising the breakout collar so that the quill passes within the breakout collar opening ( 52 ).
Adjacent to the first channels ( 26 ) are sockets ( 28 ). Adjacent to the sockets are second channels ( 30 ) which are of a similar width and run parallel to the first channels. The sockets ( 28 ) are of a sufficient size to accept the keys ( 48 ). In an embodiment, the second channels ( 30 ) terminate prior to exiting the upper end of the breakout collar. The second channels terminate in that the keys ( 48 ) are prevented from exiting the upper end of the breakout collar directly from the second channels. This can be seen in FIG. 1 and FIG. 7 .
Quill ( 40 ) has slots ( 46 ) for the placement of keys ( 48 ). The keys are placed into to the slots and held in place by the breakout collar. The keys may be replaced, as may become necessary as a result of ware or other causes, by separating the breakout collar from the quill to free the keys. The quill has a male threaded end ( 42 ) which is suited to mate with the female threaded end ( 55 ) of the drill pipe ( 50 ).
In an embodiment, the first channel ( 26 ) is unobstructed from the upper end of the breakout collar to the lower end of the breakout collar. This can be seen in FIG. 1 and FIG. 7 . The first channel is unobstructed in that a key may move into the first channel at the upper end of the breakout collar, and travel the length of the breakout collar without encountering an obstruction sufficient to prevent the key from exiting the lower end of the breakout collar.
A ring ( 32 ) is suited to attach to the top of the breakout collar ( 20 ). The ring fits within a flange ( 34 ) of the breakout collar and rests on a ring contact surface ( 36 ) of the breakout collar. The ring is attached to the breakout collar by screws ( 38 ) which pass through ring screw holes ( 40 ) to mate with ring contact surface threaded holes ( 42 ) located in the ring contact surface.
In an embodiment, the breakout collar ( 20 ) is located around the quill ( 40 ) by first raising the ring ( 32 ) so that the quill passes through the ring opening ( 44 ). The ring is raised until the ring is above the slots ( 46 ). Keys ( 48 ) are then placed in slots on opposite sides of the quill. The breakout collar is then raised so that the quill passes through the breakout collar opening ( 52 ). The breakout collar is raised until the keys ( 48 ) slide within the first channels ( 26 ) of the breakout collar. The ring is then attached to the top or upper end of the breakout collar by screws ( 38 ). In this manner, the keys are prevented from exiting the top of the first channels as the ring obstructs the first channels at the top of the breakout collar.
For moving the breakout collar to a disengaged position, the breakout collar is raised in a first direction along the quill so that the key ( 48 ) is aligned with the socket ( 28 ). For moving the breakout collar into a secured position, the breakout collar is then rotated so that the key slides into the socket, and lowered in a second direction so that the key is contained within the second channel ( 30 ). In this manner the key supports the breakout collar in a disengaged and secured position. In an embodiment, the second direction is opposite or substantially opposite to the first direction. The second direction is substantially opposite to the first direction if a component vector of the first direction is opposite of a component vector of the second direction. In the disengaged and secured position, the breakout collar is prevented from moving to an engaged position unless the above method is reversed.
FIG. 2 depicts the breakout collar ( 20 ) in the engaged position. The quill ( 40 ) is threadedly attached to a section of drill pipe ( 50 ). In the engaged position, the keys ( 48 ) are contained entirely within the upper portion of the first channels ( 26 ). The upper section of the drill pipe is contained within the lower section of the breakout collar. In the engaged position, the keys prevent the breakout collar from rotating around the quill. The Ring ( 32 ) is shown attached to the top of the breakout collar. The ring prevents the keys from exiting the top of the first channels.
FIG. 3 depicts the breakout collar in the disengaged and secured position. Key ( 48 ) is contained within the second channel ( 30 ).
FIG. 4 is an elevation view of the breakout collar having a flange ( 34 ). The flange aids in moving the breakout collar from an engaged to a disengaged position by providing an abutment surface for an operator to rest his or her hand against.
FIG. 5 is a plan view of the breakout collar without the ring ( 32 ). In this view, with the ring removed, the first channels ( 26 ) are exposed.
FIG. 6 is a bottom view of the breakout collar showing the first channels ( 26 ) on opposite sides of the internal face ( 24 ) of the breakout collar. The breakout collar has contact points ( 54 ) on opposite sides of the internal face of the breakout collar. The contact points each have a pipe contact surface ( 56 ) that contacts the key stock ( 58 ) of the drill pipe ( 50 ) when the breakout collar is in the engaged position. In this manner, the drill pipe is prevented from rotating in relation to the quill ( 40 ), and the threaded connection between the drill pipe and the quill is prevented from separating, when the quill is rotated in the reverse or unthreading direction.
FIG. 7 is a sectional view taken along line 7 - 7 of FIG. 5 . Adjacent to the first channel ( 26 ) is a socket ( 28 ). Adjacent to the socket is a second channel ( 30 ). The contact points ( 54 ) extend only partially around the circumference of the internal face ( 24 ) of the breakout collar, thus allowing for the breakout collar to be lowered over the drill pipe ( 50 ) with the key stock ( 58 ) of the drill pipe in any position other than directly below the contact point.
The breakout collar ( 20 ) is moved from a disengaged position to an engaged position by raising the breakout collar so that the keys ( 48 ) of the quill ( 40 ) move from the second channel ( 30 ) to the socket ( 28 ). The breakout collar is then rotated so that the keys move from the socket to the first channel ( 26 ) then lowered so that the keys slide to the top of the first channel, and the bottom of the breakout collar slides over the top of the drill pipe ( 50 ), which in operation has been threadedly connected to the quill. The quill and breakout collar assembly is then rotated until the contact surface ( 56 ) of the contact points ( 54 ) comes into contact with the key stock ( 58 ) of the drill pipe ( 50 ). In this manner the quill, breakout collar and drill pipe are all locked in position so that no one part may rotate in relation to another part. In operation, the quill is then rotated in the reverse or unthreading direction as the end of the next lower section of drill pipe is held in position by a slip and slip bowl assembly, wrench, tong wrench or any other method of locking or securing the drill pipe in place. In this manner the threaded connection between the upper section of drill pipe and the next lower section of drill pipe may be broken.
FIG. 8 is a sectional view taken along line 8 - 8 of FIG. 5 depicting the internal face ( 24 ) of the breakout collar. Sockets ( 28 ) and second channels ( 30 ) are shown on opposite sides of the internal face of the breakout collar. The contact point ( 54 ) has a sloped edge ( 60 ) that allows the breakout collar ( 20 ) to be lowered over the drill pipe ( 50 ) in a wider variety of rotational positions.
FIG. 9 depicts an alternative embodiment in which a breakout collar ( 170 ) has a key ( 172 ) on the internal face ( 174 ) of the breakout collar. The breakout collar has a contact point ( 176 ) with a contact surface ( 178 ). The alternative quill has a first channel ( 192 ), socket ( 194 ), and second channel ( 196 ) that are located in the quill ( 190 ). The drill pipe ( 200 ) comprises a key stock ( 202 ) and a female threaded end ( 204 ).
FIG. 10 depicts a second alternative embodiment in which a breakout collar ( 300 ) has a first key ( 302 ) and a second key ( 304 ). The quill ( 320 ) has a first channel ( 322 ) which is of a width sufficient to allow the first key and the second key to slide in the first channel. The breakout collar is moved to a disengaged position by raising the breakout collar so that the first key and the second key are aligned with sockets ( 324 ). The breakout collar is then rotated so that the first key and the second key slide into the sockets. The breakout collar is then lowered so that the first key and the second key slide into the second channels ( 326 ).
The alternative embodiment shown in FIG. 10 also has a drill pipe ( 340 ) with drill pipe channels ( 342 ). The drill pipe ( 340 ) also has a female threaded end ( 344 ).
The breakout collar ( 300 ) is moved from a disengaged position to an engaged position by raising the breakout collar so that the first key ( 302 ) and the second key ( 304 ) of the breakout collar ( 300 ) move from the second channels ( 326 ) to the sockets ( 324 ). The breakout collar is then rotated so that the keys move from the sockets to the first channel ( 322 ) then lowered so that the second key ( 304 ) slides into the drill pipe channel ( 342 ) of the drill pipe ( 340 ), which in operation has been threadedly connected to the quill ( 320 ). In this manner the quill, breakout collar and drill pipe are all locked in position so that no one part may rotate in relation to another part.
It is thought that the method and device for supporting the breakout device in a position as described herein and many of its intended advantages will be understood from the foregoing description. It is also thought that various changes in form, construction, and arrangement of the parts of the method and device may be made without departing from the spirit and scope of the embodiments described herein. The form herein described is intended to be merely an illustrative embodiment of the method and device. The claims should not be construed as limited to the specific forms shown and described, but instead is as set forth in the following claims. | A method and apparatus for supporting a tubular breakout device in a position. An embodiment of the device comprises a first channel in the inside face of the device for receiving a corresponding key of a quill, a socket adjacent to the first channel, and a second channel adjacent to the socket. An embodiment of the device is moved from the engaged position to the disengaged and supported position by the method of moving the device from an engaged position to a disengaged position, rotating the device so that the key of the quill slides into the socket of the device, then moving the device to a secured position by lowering the device so that the key of the quill slides into the second channel of the device. | 4 |
FIELD OF THE INVENTION AND RELATED ART
[0001] The present invention relates to an image forming apparatus which forms an image through an electrophotographic process. In particular, it relates to an image forming apparatus such as a copying machine, a printer, a facsimileing machine, or the like.
[0002] As one of the electrophotographic image forming apparatuses such as a copying machine, a laser beam printer, etc., a full-color image forming apparatus which forms a full-color image by depositing in layers a plurality of monochromatic images different in color, more specifically, yellow (H), magenta (M), cyan (C), and black (Bk) images, has been known.
[0003] For the formation of a high quality image with use of a full-color image forming apparatus such as the above described one, density control is important, which regulates the apparatus in terms of the maximum and intermediary levels of density for monochromatic yellow (Y), magenta (M), cyan (C), and black (Bk) images so that the apparatus will remain consistent in terms of the image density level, regardless of the difference in manufacture tolerance and changes in ambient conditions. Therefore, it is customary to equip a full-color image forming apparatus with a density controlling means for controlling the apparatus in terms of image density.
[0004] There have been proposed various full-color image forming apparatuses equipped with a density detecting means Some of them (for example, one disclosed in Japanese Laid-open Patent Application 2000-231279) are provided with a plurality of image bearing members and a plurality of developing means. Further, at least two of the plurality of developing means are identical in the hue of the developer (toner) therein, but, are different in density (saturation or deepness) of the developer (toner) therein; the developer in one of the two developing means is the same in hue as the developer in the other developing means, but is lower in density than the developer in the other developing means. They employ an image forming method in which each of the plurality of monochromatic images formed to form a single full-color image is formed of a combination of two monochromatic images identical in spectral properties, that is, a monochromatic image formed of the abovementioned developer lower in color density level (which hereinafter will be referred to light color toner), and a monochromatic image formed of the abovementioned developer higher in color density level (which hereinafter will be referred to as deep color toner), using two kinds of lookup tables, that is, a lookup table A for the light color toner, and a lookup table B for the deep color toner, shown in FIG. 13 .
[0005] According to the lookup tables in FIG. 13 , the low density areas of the monochromatic image are primarily formed of the light color toner, and the mid density areas of the monochromatic image are formed of the mixture of the light and deep color toners. Further, the high density areas of the monochromatic image are primarily formed of the deep color toner. Therefore, controlling the image forming apparatus with reference to these lookup tables A and B makes it possible to form an image which does not suffer from the problem that the low density areas of an image appear grainy due the low dot density, and also, to reduce the amount of toner which is consumed for the formation of the high density areas of an image. In other words, controlling the image forming apparatus with reference to these lookup tables improves the image forming apparatus in terms of image quality by reducing the graininess level at which the low density areas of an image are formed. It also effective to expand the range in which an image is accurately formed in terms of color reproduction.
[0006] However, the above described image forming method suffers from the following problem. That is, as a large number of images are formed, that is, the image forming apparatus is repeatedly used for a large number of times, changes occur to various conditions under which an image is formed; changes occur to the developing means in terms of development properties, the thickness of the dielectric layer of the photosensitive drum, the transfer efficiency, etc. Changes also occur to the ambient conditions. As these changes occur, the light color toner and the deep color toner change in the γ properties, and the occurrence of this change in the γ property corresponds to the threshold value for the input video signal, below which the light color toner is used, and above which the deep color toner is used. Therefore, the linearity in the relationship between the values of input video signals and the density level of the corresponding areas of the resultant image is lost. As a result, a defective image is formed; for example, an image defective in that the areas of the image, which are intermediary in density, are unnatural in gradation, and an image defective in that it has pseudo-contours.
SUMMARY OF THE INVENTION
[0007] The primary object of the present invention is to provide an image forming apparatus capable of an image higher in quality than an image forming apparatus in accordance with the prior art.
[0008] Another object of the present invention is to provide an image forming apparatus superior to an image forming apparatus in accordance with the prior art, in that it is capable of an image superior in the reproduction of the transitional areas of the image, transitional in that the image density changes from the level to be reproduced with the use of the light color toner to the level to be reproduced with the use of the deep color toner.
[0009] These and other objects, features, and advantages of the present invention will become more apparent upon consideration of the following description of the-preferred embodiments of the present invention, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic sectional view of the image forming apparatus in the first embodiment of the present invention, showing-the general structure thereof.
[0011] FIG. 2 is a flowchart which shows the flow of video signals in the image forming apparatus in the first embodiment.
[0012] FIG. 3 is a schematic drawing of an example of a density detecting means in accordance with the present invention.
[0013] FIG. 4 is a graph showing the relationship between the amount of the light color toner on the medium, and the output of the density detecting means, and the relationship between the amount of the deep color toner on the medium, and the output of the density detecting means.
[0014] FIG. 5 is a graph showing the relationship between the values of the input video signals, and the density levels of the images resultant from the input video signals, after the adjustment of the input video signals based on the lookup tables.
[0015] FIG. 6 is a graph showing the effect of the changes in image formation conditions and/or ambient conditions upon the relationship between the value of the input video signals, and the density levels of the images resulting from the input video signals.
[0016] FIG. 7 is a graph showing the relationship between the values of the input video signals generated for the formation of the density level test patches, and the density levels of the images of the test patches resulting from the input video signals for the formation of the density level test patches.
[0017] FIG. 8 is a graph showing the LUT for the light color toner, and the LUT for the deep color toner, in the first embodiment.
[0018] FIG. 9 is a graph showing the relationship between the values of the input video signals generated for the formation of the density level test patches, and the density levels of the images of the test patches resulting from the input video signals for the formation of the density level test patches.
[0019] FIG. 10 is a schematic drawing of the image forming apparatus in the second embodiment, showing the general structure thereof.
[0020] FIG. 11 is a picture of the density level detection test patches in the third embodiment.
[0021] FIG. 12 is a schematic drawing of the image forming apparatus in the fourth embodiment, showing the general structure thereof.
[0022] FIG. 13 is a graph showing the LUT for the light color toner, and the LUT for the deep color toner, for an image forming apparatus in accordance with the prior art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] Hereinafter, the image forming apparatuses in accordance with the present invention will be described in detail with reference to the appended drawings.
Embodiment 1
[0024] Referring to FIGS. 1-9 , the first embodiment of the present invention will be described.
[0025] Referring to FIG. 1 , the image forming apparatus in this embodiment has four processing stations (image forming stations) P (Pa, Pb, Pc, and Pd) as image forming means for forming monochromatic yellow (Y), magenta (M), cyan (C), and black (Bk) images on the four image bearing members, one for one. The four processing stations are aligned straight in the direction in which a recording medium is conveyed. Each processing station has a photosensitive drum 1 ( 1 a, 1 b, 1 c, and 1 d ), a charging apparatus 2 ( 2 a, 2 b, 2 c, and 2 d ), an exposing apparatus 3 ( 3 a, 3 b, 3 c, and 3 d ), a primary developing means 4 ( 4 a, 4 b, 4 c, and 4 d ), a second developing means 5 ( 5 a, 5 b, 5 c, and 5 d ), a cleaning apparatus 6 ( 6 a, 6 b, 6 c, and 6 d ), and a primary transferring means 7 ( 7 a, 7 b, 7 c, and 7 d ) as a transferring means. The image forming apparatus is provided with an intermediary transfer member 12 as a transferring means for transferring, in coordination with the primary transferring apparatuses 7 , the toner images onto a recording medium p. The intermediary transfer member 12 is stretched between the photosensitive drum 1 and primary transferring apparatus 7 , in each processing station, and is circularly moved in the direction indicated by an arrow mark.
[0026] In this image forming apparatus structured as described above, each of the four image forming stations for forming the four monochromatic toner images, that is, the monochromatic yellow (Y), magenta (M), cyan (C), and black (Bk) toner images, one for one, is provided with two developing means, that is, the first and second developing means 4 and 5 ; two developing means are provided per color. More specifically, the first and second developing means are identical in the color (hue) of the toners therein, but are different in the color density of the toners therein. That is, the first developing means 4 is filled with such developer that is the same in hue, but is lighter in color density (saturation) than the toner in the second developing means 5 .
[0027] In other words, the image forming apparatus in this embodiment has two developing means, that is, the deep color developing means 5 and light color developing means 4 , for each of the four colors, that is, yellow (Y), magenta (M), cyan (C), and black ( 8 k). The deep color developing means 5 and light color developing means 4 are the same in the hue of the toner of the developer they contain, but are different in the color density (saturation) of the toner of the developer they contain; the color of the toner in the second developing means 5 is darker (deeper) than that in the first developing means 4 .
[0028] When it is said that ordinary two toners, which primarily are the mixture of resin and coloring component (pigment), are the same in hue, but different in density (saturation), it usually means that the two toners are practically the same in the spectral characteristics of the coloring ingredient (pigment), but are different in the amount of the coloring component. When one is called “light color toner” of the two toners which are the same in color (hue), the light color toner is the one which is lower in color density (saturation).
[0029] The image forming apparatus in this embodiment uses two toners different in color density in order to form a monochromatic toner image of a given color, and the two toners different in color density used for forming a single monochromatic toner image may sometimes be referred to as “dense (dark) toner” and “light toner”.
[0030] When two toners are said to be the same in hue, it means that the two toners are the same in the spectral characteristics of the coloring component (pigment) as described above. In the following description of the present invention, however, it means that the two toners are the same in terms of the ordinary concept of color. For example, two toners may be said to be the same in hue in that both are of magenta, cyan, yellow, or black color.
[0031] In the following description of the present invention, when one of the two toners of the same hue is referred to as light color toner, it means that when the amount by which this toner is deposited on recording medium is 0.5 mg/cm 2 , the portion of the recording medium covered with this toner is no more than 1.0 in optical density after the image fixation, whereas the portion of the recording medium covered with the other toner, or the deep color toner (toner more saturated in color) is no less than 1.0 in optical density.
[0032] In this embodiment, the amount of the pigment in the deep color toner is adjusted so that when the amount by which the deep color toner is deposited on recording medium is 0.5 mg/cm 2 , the optical density of the recording medium covered with this toner is 1.6, whereas that for the light color toner is 0.8. These two toners different in color density (saturation) are used in various ratios to reproduce a desired level (gradation level) of color density.
[0033] In terms of the direction, indicated by an arrow mark, in which the photosensitive drum 1 is rotated, the first developing means 4 is located on the upstream of the second developing means 5 .
[0034] The normal image forming steps carried out to form an image, by the image forming apparatus structured as described above are as follows:
[0035] In each of the plurality of process stations P, a toner image, which is different in color from the toner images in the other processing stations P, is formed on the photosensitive drum 1 through the electrophotographic process (comprising: charging, exposing, and developing steps).
[0036] First, in each processing station P, the charging step, in which the peripheral surface of the photosensitive drum 1 is uniformly charged by the charging apparatus 2 as a charging means, is carried out.
[0037] Meanwhile, in each processing station P, image formation data are read by an image reading portion 20 , are processed by a controlling means 15 as the controller for controlling the image forming operation, and are transmitted to a laser driver 3 ( 3 a, 3 b, 3 c, and 3 d ), which is a part of the exposing apparatus as a latent image forming means for forming a latent image on the photosensitive drum 1 .
[0038] In this embodiment, an original is read twice by the original reading portion 20 , for each processing station. More specifically, when the original is read for the first time, the obtained image formation data are processed by the controlling means 15 into the video signals for the first developing means 4 , whereas when the original is read for the second time, the obtained image formation data are processed by the controlling means 15 into the video signals for the second developing means 5 . The flowchart which shows the essential steps of this process of outputting the video signals is given in FIG. 2
[0039] First, regarding the first reading of an original for the formation of a latent image (exposure of photosensitive drum 1 ), the original placed on the original reading portion 20 is scanned (si), and the optical data obtained from the original are converted (s 1 ) by a CCD 14 into electrical signals, which are converted (s 3 ) by an A/D conversion apparatus into digital signals. The thus obtained digital signals are processed (s 4 ) by the image formation data processing block, and the R, G, and B signals are converted (s 5 ) in color into CMYK signals. Then, the CMYK signals are subjected to the γ correction step (s 6 ), and are converted (s 7 ) into the video signals for the light color toner, in accordance with the lookup table (which hereinafter will be referred to as “LUT”). Then, the video signals for the light color toner are digitized (s 8 ). The thus obtained digital image formation data are stored (s 9 ), are converted (s 10 ) into analog signals, are transferred to the laser driver 3 , and are used (s 11 ) for image formation. The LUT for the light color toner, which is used in the above described step s 7 , is represented by the line indicated by a referential letter A, in FIG. 8 .
[0040] The electrostatic latent image formed through the exposure in the above described step (s 11 ) is developed by the first developing means 4 which uses the light color toner. Then, the toner image formed by the first developing means 4 is transferred (primary transfer) onto the intermediary transfer belt 12 by the primary transferring apparatus 7 as a transferring means.
[0041] Then, the original is scanned for the second time (s 12 ). In order to form a toner image of the deep color toner after forming a toner image of the light color toner, it is necessary to read (scan) the original again, due to requirement related to the memory. The image formation signals obtained by the second scanning of the original are processed through steps (s 12 -s 17 ) similar to the steps through which the image formation signals obtained by the first scanning of the original are processed, up to the correction step. Thereafter, the signals are converted (s 18 ) into the signals for the deep color toner, in accordance with the LUT for the deep color toner, and then, are digitized (s 19 ). The thus obtained digital image formation data are stored (s 20 ), are converted (s 21 ) into analog signals, are transferred to laser driver 3 , and are used to drive (s 22 ) the laser driver 3 to form an image of the deep color toner. The LUT to be used in the step (s 18 ) to obtain the signals for the deep color toner is represented by the line indicated by a letter B, in FIG. 8 .
[0042] As the above described step s 22 , or the latent image formation step, is carried out, an electrostatic latent image is formed, through the exposure, on the uniformly charged peripheral surface of the photosensitive drum 1 . Next, this electrostatic latent image is developed through the developing step carried out by the second developing means 5 which uses the deep color toner, yielding a toner image formed of the deep color toner The thus obtained toner image is transferred (primary transfer) by the primary transferring apparatus 7 , onto the intermediary transfer belt 12 , onto which the toner image formed of the light color toner has been transferred. As a result, a toner image formed of the deep color toner and light color toner is yielded on the intermediary transfer belt 12 .
[0043] In other words, through the video signal processing steps shown in FIG. 2 , the original is sorted into the areas which are to be reproduced with the use of only the light color toner, the areas which are to be reproduced with the use of both the light and deep color toners, and the areas which are to be reproduced with the use of only the deep color toner, and then, whether only one of the developing means 4 and 5 is to be used, or which developing means is to be used if only one of the developing means 4 and 5 is to be used, is determined based on the results of the sorting.
[0044] As for the transferring means, the intermediary transfer member 12 is circularly moved by the suspensive rollers 12 a and 12 b at the same speed as the rotational velocity of each of the plurality of photosensitive drums 1 , through the contact area (nip) between the primary transferring apparatus 7 and photosensitive drum 1 , in each processing station P (Pa, Pb, Pc, and Pd), with its outwardly facing surface, in terms of the loop which the intermediary transfer member 12 forms, kept in contact with the peripheral surface of the photosensitive drum 1 . Thus, as the intermediary transfer member 12 is moved sequentially through the plurality of primary transfer stations, the toner image formed on the peripheral surface of the photosensitive drum 1 , of the two toner images formed in layers on the peripheral surface of the photosensitive drum 1 , of the two toners different in color density, in each processing station P (Pa, Pb, Pc, and Pd) is transferred in layers onto the intermediary transfer member 12 , yielding a single multicolor image, which is conveyed, while remaining on the intermediary transfer member 12 , to the secondary transfer station 11 , by the circularly movement of the intermediary transfer member 12 .
[0045] The multicolor image formed on the intermediary transfer member 12 , of the plurality of monochromatic toner images formed of the two toners different in color density, in the plurality of processing stations P, one for one, is transferred (secondary transfer) in the secondary transfer station 11 , onto the recording medium p delivered to the secondary transfer station 11 from the sheet feeder cassette 13 , and then, is fixed to the recording medium p by the fixing apparatus 9 . Thereafter, the recording medium p is discharged as a final product (copy) from the image forming apparatus.
[0046] In other words, according to the flowchart given in FIG. 2 , the image formation signals are processed, in the step s 7 , in accordance with the LUT for the light color toner, so that the areas of the image, which are low in color density, are primarily developed with the light color toner. As a result, the latent image is developed so that a monochromatic image, the low color density areas of which are lower in the color density of each dot, will be yielded In other words, the flowchart makes it possible to minimize the shortcoming of a digital image that a digital image appears grainy. Further, another set of image formation signals are processed, in step p 18 , in accordance with the LUT for the deep color toner. In other words, according to the flowchart in FIG. 2 , two monochromatic images different in color density are formed per color component (into which optical image of original is separated), through two sets of image formation steps, that is, the image formation signal processing step, latent image forming step, and developing step, and are transferred in layers onto the intermediary transfer belt 12 , through the primary transfer step, yielding thereby a single monochromatic image formed of two monochromatic images formed of the deep and light color toners, one for one, which are the same in hue and different in color density.
[0047] Described next will be the control to be carried out to form a satisfactory image, regardless of the changes in the apparatus conditions attributable to the usage and the changes in the ambient conditions, through an image forming process such as the one described above, in which two developing means different in the color density of the toners they use are used per color component. In this embodiment, the image forming process is controlled by revising the LUTs used for processing the video signals.
[0048] To describe in more detail, the above described image forming apparatus is reset so that the image formation conditions, such as the conditions under which the photosensitive drums 1 are charged and exposed by the image forming means, the conditions under which a latent image is developed, and the conditions under which a toner image is transferred, are set to the defaults. Then, the data for generating the video signals for forming density level detection test patches, which are stored in the ROM or the like, are read by the means for forming the electrostatic latent images for density level detection test, that is, a density level detection test patch forming means, for example, the controller (controlling means) 15 , and a desired image density level is inputted. Then, the electrostatic latent image for density level detection test, which reflects the inputted image density level is formed, and is developed by the developing means to be used for developing the latent image in accordance with the intended image. As a result, the image of the density level detection test patch (images to be used for devising LUT) is formed, and is transferred (primary transfer) onto the intermediary transfer medium 12 . Then, the color density level of the toner image of the density level detection test patch on the intermediary transfer member 12 is detected by the density detecting means (density sensor) 21 , which is positioned upstream of the second transfer station 11 , in terms of the moving direction of the intermediary transfer member 12 , so that it faces the intermediary transfer belt 12 . The thus obtained density level of the image of the density level detection test patch is used as the output density level.
[0049] Then, based on the relationship between the inputted color density level, and the outputted color density level detected by the color density sensor 21 , the controller 15 as a controlling means adjusts the image formation conditions, as will be described below, in order to yield a satisfactory image. More specifically, the gradation reference, which in this embodiment is the LUT, set in the video signal processing portion of the controller 15 , is revised so that a satisfactory (vivid) image, in terms of gradation, is always formed regardless of the gradational variations.
[0050] Referring to FIG. 3 , the density sensor 21 in this embodiment comprises a light emitting element 23 , a light receiving element 24 such as a photo-diode, Cds, or the like, and a holder 22 to which the light emitting element 23 and light receiving element 24 are attached. The beam of light from the light emitting element 23 is projected onto the image T of the density detection patch (which hereinafter will be referred to patch image T) on the belt 12 , and is partially received by the light receiving element 24 after being deflected (diffused) by the patch image T, in order to measure the density level of the patch image T. Generally, light reflected by a given surface includes the portion literally reflected by the surface and the portion diffused by the surface. In this embodiment, a density sensor of the diffuse light type is used as the density sensor 21 , and the incident angle θ and reflection angle φ are set to 15° and 45°, respectively. The outputs of the density sensor 21 when the light color toner was used, and the outputs of the density sensor 21 when the deep color toner was used, are given in FIG. 4 .
[0051] The controlling means 15 automatically revises the gradation setting, in real time, by changing the values set in the lookup table stored in the γ correcting portion of the video signal processing portion, based on, for example, a LUT revision table, in response to the image density level of the patch image T detected by the density sensor 21 .
[0052] Further, the controlling means 15 stabilizes the image forming apparatus in terms of image quality, by sequentially revising the image formation conditions, that is, the conditions under which the photosensitive drums 1 are charged, the conditions under which the photosensitive drums 1 are exposed, the conditions under which images are transferred, etc., which are set in the video signal processing portion. In other words, the controlling means 15 stabilizes the image forming apparatus in terms of image quality by revising the image formation conditions. Since the image forming apparatus is controlled in image density, based on the LUT revised through the above described steps, the relationship between the input video signals and the density of the image resultant from the inputted video signals becomes linear, as shown in FIG. 5 , making it possible to yield an image satisfactory in terms of density level reproduction. Referring to FIG. 5 , incidentally, the input video signals means the video signals resulting from the reading of the original by the original reading apparatus 20 , and the output image density level means the density level of the image resulting from the input video signals.
[0053] As described above, in this embodiment, the image formation operation is controlled by the controlling means 15 in accordance with the LUT. Therefore, a satisfactory image can be formed.
[0054] However, as a large number of copies are made, that is, the image forming operation is repeated a large number of times, and/or the ambient conditions of the image forming apparatus change, the image formation conditions, such as the developmental properties of the developing means 4 and 5 , the thickness of the dielectric layer of the photosensitive drum 1 , the transfer efficiency or the like in the secondary transfer station 11 , change. As a result, the light and deep color toners change in the γ property, making nonlinear the relationship between input image density level and output image density level, roughly at the density level (which hereinafter will be referred to as mid image density level) where the light color toner and deep color toner begin to be used in mixture, as shown in FIG. 6 . Therefore, it becomes unlikely for an image satisfactory in terms of color density reproduction to be formed. Instead, an unsatisfactory image, for example, an image unnatural in gradation across the areas where color density is in the mid range, an image suffering from pseudo-contours, or the like, is likely to be yielded.
[0055] In this embodiment, therefore, the image density levels to be inputted for forming the images of the density level detection test patches for revising the LUT are selected so that the detection of the density levels of the patch images, the density levels of which are at, or in the adjacencies of, the mid image density level, is prioritized.
[0056] In this embodiment, as the values for the video signals to be inputted to form the patch images for determining the relationship between the input signal level and the output density level, 16 , 48 , 80 , 112 , 120 , 128 , 136 , 144 , 176 , 208 , and 240 are selected from among the 255 values (that is, 256 gradation levels) used to indicate the density level of an image of a solid color. FIG. 7 , in which the abovementioned values for the video signals inputted for patch formation, and the corresponding density levels of the patch images, are plotted, shows the relationship between the input signals and output signals in terms of the image density. As will be evident from this graph, the values for the input video signal are selected so that the interval between the adjacent two values is smaller, near 128 ; in other words, the detection of the density level is concentrated to the values near 128 .
[0057] More specifically, the abovementioned values are selected in consideration of the following facts (problems). That is, not only is it difficult to confirm whether or not the relationship between the input video signal and the density level of the resultant image is linear in the areas of the image, where the density is in the mid range, but also, if the larger the interval between the adjacent two density levels selected for the density level detection test patches, the more unclear the changes in the γ property, whereas the narrower the interval, the greater the number of the patch images to be formed to detect the relationship between the input video signals and the density level of the resultant image, and therefore, the longer the down time, or the time spent to detect the relationship, and also, the greater the toner consumption, and therefore, the higher the image formation cost.
[0058] More specifically, the number by which the patch images, which are formed of the mixture of the light and deep color toners, and the image density levels of which are in the adjacencies of the borderline density level between the density level range in which patch images are formed of the light color toner alone, and the density level range in which patch images are formed of the mixture of the light and deep color toners, are formed, and the number by which the patch images, which are formed of the mixture of the light and deep color toners, and the image density levels of which are in the adjacencies of the border line density level between the density level range in which patch images are formed of the mixture of the light and deep color toners, and the density level range in which patch images are formed of the deep color toner alone, are formed, are made greater than the number by which the patch images which are formed with the use of the deep color toner alone, and the density levels of which are in the mid to high portion of the density level range in which patch images are formed of the deep color toner alone, are formed, and the number by which the patch images, which are formed of the light color toner alone, and the density levels of which are in the low to mid portion of the density level range in which patch images are formed of the light color toner alone, are formed.
[0059] As described above, it is desired that the patch images, the image density levels of which fall within the adjacencies of the mid density level at which the toner used for forming a monochromatic image is switched from the light color toner to the mixture of the light and deep color toners, are formed by a greater number than the patch images, the image density levels of which do not fall within the abovementioned range, and their actual density levels are detected.
[0060] Referring to FIG. 8 , in which in order to make it easier to understand the abovementioned mid density levels, the overall range of the values for the input video signals are divided into an image density range R 1 in which only the light color toner is used, an image density range R 2 in which the mixture of the light and deep color toners are used, and an image density range R 3 in which only the deep color toner is used, the abovementioned mid density level means the borderline between the image density ranges R 1 and R 2 .
[0061] In other words, the patch images, the theoretical density levels of which fall within the adjacencies of the borderline between the image density ranges R 1 and R 2 , are formed by a larger number than the patch images, the theoretical density levels of which do not fall therein, and their actual density levels are detected by the density sensor 21 to more precisely determine the relationship between the input density and output density. Therefore, it is possible to keep linear the relationship between the input density level and output density level. In other words, it is possible to satisfactorily control the image density.
[0062] Referring to FIG. 9 , regarding one of the characteristic features of this embodiment of the present invention, the image density can be even more satisfactorily controlled by forming, by a greater number, the patch images, the theoretical density levels of which fall within the adjacencies of the borderline between the image density ranges R 2 and R 3 , in addition to the patch images, the theoretical density levels of which fall within the adjacencies of the borderline between the image density ranges R 1 and R 2 , than the patch images, the theoretical density levels of which do not fall therein.
[0063] The reason not only are the patch images, the image density levels of which fall within the adjacencies of the intermediary density level, that is, the borderline between the image density ranges R 1 and R 2 , that is, the borderline between the image density range in which only the light color toner is used, and the image density range in which the light color toner is used in combination with the deep color toner, but also, the patch images, the image density levels of which fall within the adjacencies of the intermediary density level, that is, the borderline between the image density ranges R 2 and R 3 , are formed by a greater number than the patch images, the density levels of which do not fall in the adjacencies of the borderline between the image density ranges R 1 and R 2 , and the adjacencies of the image density range R 2 and R 3 , is that the effects of the changes which occur to the developing means through the usage, upon the γ property, and the effects of the changes in the ambient conditions, upon the γ property, are larger when the image density level of the portion of the image being formed is at or in the adjacencies of these borderlines.
[0064] As will be evident from the above description of this embodiment, in the case of the image forming apparatus in this embodiment, in which each of the plurality of monochromatic images, different in color, formed to form a single multicolor image, is formed of two toners, that is, light and deep color toners, which are the same in hue, but, are different in color density, and the image density is controlled by revising the LUT in response to the output of the density sensor which detects the image density levels of the images of the density level detection test patches, the formation of the patch images, the image density levels of which fall in the adjacencies of the image density level at which the toner used for the formation of the monochromatic image is switched from the light color toner to the mixture of the light and deep color toners, is prioritized, and the density levels of the resultant patch images are detected by the density sensor. Therefore, even if the processing conditions of the image forming apparatus change due to the formation of a large number of images (copies), and/or the ambient conditions change, the relationship between the video signals and the density level of the image resulting from the video signals remains linear, making it possible to always form a color image of high quality.
Embodiment 2
[0065] Next, referring to FIG. 10 , the second embodiment of the present invention will be described.
[0066] In this embodiment, the image formation stations Pb and Pc for forming the magenta (M) and cyan (C) images are provided with both the first and second developing means 4 and 5 in the above described first embodiment, and the image formation stations Pa and Pd for forming the yellow (Y) and black (Bk) images are provided with only the second developing means 5 , that is, the developing means which uses the deep color toner.
[0067] Yellow (Y) color is higher in brightness. Therefore, the graininess of the yellow areas of an image is difficult to visually detect, even if the areas are low in density. Thus, the effect of the usage of the light yellow toner is insignificant.
[0068] As for black (Bk) color, it is rare that photographic image or the like images, which require high quality, have black areas which are low in density. Further, a letter or the like image usually is solid. Therefore, effect of the usage of the light black toner is insignificant.
[0069] In this embodiment, the process of forming a magenta (M) image and the process of forming a cyan (C) image are controlled in the manner similar to that in the first embodiment. As a result, the relationship between the input video signal and the density level of the resultant image can be kept linear, making it possible to yield a color image of high quality, in terms of the density of the magenta and cyan color areas of the image, regardless of the changes in the ambient conditions, even after the developing apparatuses change in properties through the usage.
[0070] Moreover, the component count of the developing means is smaller than that in the first embodiment, and also, the memory capacity necessary for the LUT can be reduced. Therefore, it is possible to provide an image forming apparatus, which is smaller, lower in cost, and simpler to control.
Embodiment 3
[0071] Next, referring to FIG. 11 , the third embodiment of the present invention will be described. The general structure of the image forming apparatus in this embodiment is the same as that of the image forming apparatus in the first embodiment, and therefore, the same referential numbers and symbols as those used for the designation of the components, means, etc., of the image forming apparatus in the first embodiment are used to designate the corresponding component, means, etc., of this image forming apparatus.
[0072] In this embodiment, the density of the patch image formed to control the image forming apparatus in terms of image density is detected by the density sensor 21 positioned next to the intermediary transfer member 12 , facing the intermediary transfer member 12 . In this embodiment, however, the density level of the test patch image is detected by the original reading portion 20 after the test patch image is transferred onto the recording medium p, and the control is carried out in response to the thus detected image density level of the test patch image.
[0073] Referring to FIG. 11 , a test pattern print 30 contains four rows of color patches, that is, the row of the eleven yellow color patches, row of the eleven magenta color patches, row of the eleven cyan color patches, and row of the eleven black color patches. The eleven color patches in each row of color patches are different in density level (gradation level). Out of the 256 levels of density (gradation level), which this image forming apparatus is enabled to reproduce, the mid density value and the values close thereto are primarily selected as the values for the density levels for the density level detection test patches, and the images of the density level detection test patches, the density levels of which fall in the low density range, or high density range, are formed by a substantially smaller number than the number by which the images of the density level detection test patches, the density levels of which fall on or within the adjacencies of the mid density value.
[0074] Thus, the images of the density detection test patches are not formed by an excessive number. Therefore, it is possible to control the image forming apparatus in terms of the density level at which the toner used for the formation of a monochromatic image is switched from the light color toner to the mixture of the light and deep color toners, while reducing the toner consumption and the time required for forming the test prints.
[0075] As for the image density levels of the eleven test patches in each of the four rows of test patches, the density level of the test patch, which is deepest in density, is represented by a value of 255, and the values of the density levels of the eleven test patches for each color are 16 , 48 , 80 , 112 , 120 , 128 , 136 , 144 , 176 , 208 , and 240 , as they were in the first embodiment. The video signals for forming the images of these eleven test patches, the density levels of which have the above listed values, one for one, are generated with the use of the test patch generating means.
[0076] After the formation of the groups of patch images, the groups of patch images on the test print 30 are read by the original reading portion 20 .
[0077] In order to accurately detect the density level of the images of the test patches, the density level of each test patch image was detected at 16 points of the test patch, and the obtained signals are averaged. The value obtained by averaging the 16 values obtained by detecting the density level of each test patch image at 16 different points of the test patch image, RGB signals are converted by the optical density converting method into the density values for Y, M, C, and Sk, and the LOT is revised in response to the thus obtained density values for Y, M, C, and Bk; a new LUT is set up.
[0078] By carrying out the above described image density control, it was possible to maintain linearity in the relationship between the input video signals and the density level of the reproduced image, in spite of the changes in the processing conditions which occurred through an operation for forming a large number of copies, repetition of the image forming operations, and/or changes in the ambient conditions. As a result, it was possible to continuously form images of high quality.
[0079] Further, the test patch images tested for image density control in this embodiment are the test patch images which had been transferred onto the recording mediums p, and had been fixed to the recording mediums p by being put through the fixing device 9 . They are virtually the same in terms of image density level as that of the image to be formed for actual usage. Thus, the image density control in this embodiment is more accurate than that in the first embodiment.
[0080] Referring to FIGS. 1 and 10 , in the first to third embodiments, the density sensor 21 was positioned so that it faced the intermediary transfer member 12 , which was a transfer belt for a multilayer direct image transfer method. Obviously, however, the density sensor 21 may be positioned so that it faces the peripheral surface of the photosensitive drum 1 . Placing the density sensor 21 so that it faces the peripheral surface of the photosensitive drum 1 is just as effective as placing the density sensor 21 so that it faces the intermediary transfer member 12 .
Embodiment 4
[0081] Next, referring to FIG. 12 , the fourth embodiment of the present invention will be described.
[0082] This embodiment is an example of the application of the present invention to an image forming apparatus employing the multilayer direct image transferring method. In this embodiment, a plurality of image formation stations Pa-Pd, similar in structure as those shown in FIG. 1 , are disposed along the transfer belt 12 . The recording medium p from a cassette 13 is borne on the surface of the transfer belt 12 , and is conveyed by the transfer belt 12 through the image formation stations Pa-Pd, in which it remains pinched between the transfer roller 7 as a transferring means, and the photosensitive drum 1 , so that the a plurality of monochromatic toner images are transferred in layers directly onto the recording medium p. After the direct transfer, the recording medium p is conveyed through the fixing device 9 , in which the plurality of monochromatic toner images on the recording medium p are fixed. Thereafter, the recording medium p is discharged frog the image forming apparatus. Obviously, a plurality of image formation stations Pa-Pd, similar to those shown in FIG. 10 , may be disposed along the transfer belt 12 .
[0083] In this embodiment, the images of the density level test patches are formed on the portion of the transfer belt 12 other than where the recording medium p is borne, or on the recording medium p borne on the transfer belt 12 , and then, the test patch images are test for density level by the density sensor 21 . The image control in this embodiment is the same as those in the above described first to third embodiments.
[0084] According to the above described first to fourth embodiments, it is possible to keep linear the relationship between the input video signals and the density levels of the resultant images, even if the condition of an image forming apparatus changes because of the formation of a large number of images, and/or the changes in the ambient conditions. Therefore, it is possible to always form images of high quality.
[0085] Incidentally, in the above, the first to fourth embodiments were described with reference to an image forming apparatus of an inline type However, the number of the photosensitive drum 1 does not need to be limited to the number in these embodiments. For example, a plurality of developing means may be disposed in the adjacencies of the peripheral surface of a single photosensitive drum.
[0086] Further, the measurements, materials, and shapes of the structural components of the image forming apparatus, and the positional relationship among them, in the first to fourth embodiments of the present invention, are not intended to limit the scope of the present invention, unless specifically noted.
[0087] While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth, and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.
[0088] This application claims priority from Japanese Patent Application No. 433950/2003 filed Dec. 26, 2003, which is hereby incorporated by reference. | An image forming apparatus image forming means for forming a toner image using light color toner and dark color toner which have the same hues and which have different densities; detecting means for detecting a density of a toner image for reference which is formed by the image forming means, the reference toner image including a number of portions corresponding to different image density levels; control means for controlling an image forming condition of the image forming means in accordance with an output of the detecting means, wherein a difference between the image density levels corresponding to adjacent ones of the portions in a predetermined image density area including an image density level corresponding to a boundary between an image density area where an image is formed using only the light toner and an image density area where an image is formed using both of the light toner and the dark toner, is smaller than that in a density area other than the predetermined image density area. | 6 |
RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 12/704,162, entitled Lens Inserter Apparatus and Method, filed Feb. 11, 2010.
FIELD OF THE INVENTION
[0002] The present invention relates generally to ocular surgery. More particularly, the present invention relates to a method for inserting a lens into the eye to treat presbyopia.
BACKGROUND OF THE INVENTION
[0003] Presbyopia is the gradual loss of near vision, which often accompanies the aging process. The eyes of a person suffering from presbyopia have a diminished ability to focus on near objects such as books, magazines, or a computer screen. Symptoms of presbyopia can include difficulty reading fine print and blurred vision when transitioning the focus of the eye between near and distant objects.
[0004] There are several common treatments for presbyopia. A dedicated pair of reading glasses is one such treatment. Reading glasses provide magnification of near objects to provide for improved vision. However, if a person also needs glasses to focus on distant objects switching between reading glasses and distance glasses can be inconvenient. Another treatment is bifocal glasses, which provide a portion of the glasses lens for assisting with distance vision and a portion for assisting with near vision. While bifocals provide a single pair of glasses for both near and distance vision correction, they can cause disorientation. Contact lenses for the surface of the eye have also been developed which provide vision correction for both near and distance vision. Although these treatments provide vision correction for a person suffering from presbyopia, each requires at least one an additional accessory or pair of contact lenses that must be worn or used daily. Additionally, very small lenses for insertion into the eye are being developed. However, these lenses cannot be handled manually or with conventional tools.
[0005] Accordingly, it is desirable to provide an apparatus and method for inserting a lens into the cornea to improve a patient's presbyopia.
SUMMARY OF THE INVENTION
[0006] The foregoing needs are met, to a great extent, by the present invention, wherein in one aspect an apparatus is provided that in some embodiments includes a design for a lens inserter apparatus and method.
[0007] In accordance with one aspect of the present invention, a lens inserter apparatus includes a handle having a distal end and a proximal end and an outer wall of the handle defining a lumen extending through the handle and a plunger extending movably through the lumen of the handle having a distal end and a proximal end, wherein the plunger includes a distal segment which extends beyond the distal end of the handle. The lens inserter can also include an actuator coupled to the plunger configured to provide movement to the plunger. Additionally, the lens inserter can include a leaf extending from the distal end of the handle and configured to hold the lens to be inserted into the eye, wherein the leaf defines a slot configured to enable loading the lens onto the inserter.
[0008] In accordance with another aspect of the present invention the lens inserter apparatus can include two leaves. The first leaf can extend from a top surface of the distal end of the handle and the second leaf can extend from a bottom surface of the distal end of the handle. The leaves can be configured to grip the lens to be inserted into the eye. Additionally, the lens inserter can include a spring disposed within the lumen of the handle against which the plunger is biased.
[0009] In accordance with another aspect of the present invention, the actuator of the lens inserter can provide movement to the plunger about a radial axis of the plunger. In addition, the actuator can provide movement to the plunger about a longitudinal axis of the plunger. Alternately, the actuator of the lens inserter can provide movement to the plunger about a radial axis of the plunger and a longitudinal axis of the plunger.
[0010] In accordance with another aspect of the present invention, the slot of the lens inserter can be configured to couple with a post on a package holding the lens. The distal end of the distal segment of the plunger can include a fork configured to push the lens off of the leaf. Additionally, the actuator can include a finger rest, and the leaf can include a lens shaped portion to pick up and hold the lens for insertion.
[0011] In accordance with yet another aspect of the present invention, an apparatus for inserting a lens into a corneal pocket or flap includes a handle having an outer wall defining a lumen extending through the handle. The lens inserter can include a plunger extending movably through the lumen of the handle, wherein the plunger includes a distal segment, which extends beyond the distal end of the handle. The lens inserter can include an actuator coupled to the plunger and extending through an opening defined by the outer wall of the handle wherein the actuator is configured to provide movement to the plunger about a radial and longitudinal axis of the plunger. The lens inserter can also include a pair of leaves extending from the distal end of the handle and configured to grip the lens to be inserted into the eye. The leaves can define a slot configured to enable loading the lens onto the inserter, and the leaves can be biased together and can be separated by using the actuator to provide radial movement to the plunger.
[0012] In accordance with another aspect of the present invention the actuator can include a finger rest. The slot at the distal end of the leaf can be configured to couple with a post on a package holding the lens. Additionally, the distal end of the distal segment plunger can include a fork configured to push the lens off of the leaf.
[0013] In accordance with still another aspect of the present invention, a method for inserting a lens into a corneal pocket or flap includes opening a set of leaves of a device for inserting the lens into the pocket in the cornea; and positioning a slot at a distal end of one of the leaves over a post on a packaging of the lens. The method further includes positioning the lens between the leaves of the device for inserting the lens. Additionally, the method includes inserting the lens into the corneal pocket and releasing the lens from the leaves.
[0014] In accordance with even another aspect of the present invention, the method can further include releasing the lens from the leaves by moving the actuator along a longitudinal axis of the plunger to move the plunger in a direction of a distal end of the device to insert the lens. The method can also include the leaves being biased together. The method can also include the device for inserting the lens including a spring for biasing against the plunger. The method can include using an actuator to rotate a plunger of the device about a radial axis of the plunger to open the leaves, and using the actuator to close the leaves in order to grip the lens between the two leaves.
[0015] There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
[0016] In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
[0017] As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 illustrates a side view of a lens inserter apparatus in accordance with an embodiment of the invention.
[0019] FIG. 2 illustrates a top view of a lens inserter in accordance with an embodiment of the invention.
[0020] FIG. 3 illustrates a sectional view taken along axis “A” of the embodiment shown in FIG. 2 .
[0021] FIG. 4 illustrates a perspective view of a distal end of the lens inserter apparatus in accordance with an embodiment of the invention.
[0022] FIG. 5 illustrates a top view of the distal end of the lens inserter apparatus shown in FIG. 4 .
[0023] FIG. 6 illustrates a side view of a handle of a lens inserter in accordance with an embodiment of the invention.
[0024] FIG. 7 illustrates a top view of a plunger of a lens inserter in accordance with an embodiment of the invention.
[0025] FIG. 8 illustrates a side view of a plunger of a lens inserter in accordance with an embodiment of the invention.
[0026] FIG. 9 illustrates a step in a method of inserting a lens using a lens inserter apparatus in accordance with an embodiment of the invention.
[0027] FIG. 10 illustrates a step in a method of inserting a lens using a lens inserter apparatus in accordance with an embodiment of the invention.
[0028] FIG. 11 illustrates a step in a method of inserting a lens using a lens inserter apparatus in accordance with an embodiment of the invention.
[0029] FIG. 12 illustrates a step in a method of inserting a lens using a lens inserter apparatus in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
[0030] The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. An embodiment in accordance with the present invention provides an apparatus and method for inserting a lens into a flap or pocket in the cornea. This lens or pocket preferably is created by a laser used in conventional lasik surgery. The apparatus includes a handle, a plunger extending movably through the lumen of the handle, wherein the plunger includes a distal segment that extends beyond the distal end of the handle, an actuator coupled to the plunger configured to provide movement to the plunger, and a leaf extending from the distal end of the handle and configured to hold the lens to be inserted into the eye, wherein the leaf defines a slot configured to enable loading the lens onto the inserter.
[0031] An embodiment of the present inventive apparatus is illustrated in FIG. 1 . FIG. 1 illustrates a side view of a lens inserter apparatus 10 in accordance with an embodiment of the invention. The lens inserter apparatus 10 includes a handle 12 , which has a distal end 14 and a proximal end 16 . The lens inserter 10 also includes a pair of leaves 18 and 20 , which extend from the distal end 14 of the handle 12 . Preferably, the leaves 18 and 20 have a length in a range of 10 mm to 30 mm and a width in a range of 1 mm to 4 mm. The thickness of each of leaves 18 and 20 is approximately in the range of 50 microns to 200 microns for a combined thickness in a range of 100 microns to 400 microns. The leaves can be formed from stainless steel or any other suitable non corrosive material. Top leaf 18 extends from a top surface 22 of the handle 12 , while bottom leaf 20 extends from a bottom surface of the handle 12 . The top leaf 18 and bottom leaf 20 are biased together, such that an inner surface of the top leaf 18 is in contact with an inner surface of the bottom leaf 20 , and are preferably made from a flexible, resilient material. Additionally, a plunger 26 extends through the handle 12 . The plunger 26 has a distal end portion 28 , which extends beyond the distal end 14 of the handle 12 . The plunger can be formed from titanium or stainless steel or any other suitable non corrosive material. An actuator 30 is coupled to the plunger 26 by posts 32 and 34 . The actuator 30 can be used to move the plunger 28 via finger rest 36 . The lens inserter apparatus 10 also includes a longitudinal axis “a.”
[0032] FIG. 2 illustrates a top view of a lens inserter in accordance with an embodiment of the invention. The leaves 18 and 20 have a generally flat elongate surface 38 and a distal end 40 , which has a generally circular, lens shaped portion 42 , which allows for the lens to be inserted into the eye to sit on a top surface of the bottom leaf 20 . The generally circular lens shaped portion preferably has a diameter in a range of 2 mm to 4 mm. As illustrated in FIG. 2 , the outer wall of the handle 12 also defines a slot 44 in which the actuator 30 can move in order to provide movement to the plunger 26 . The finger rest 36 of the actuator 30 can also be textured to provide friction between the actuator and the operator's finger.
[0033] FIG. 3 illustrates a sectional view taken along axis “a” of the embodiment shown in FIG. 1 . The outer wall 46 of the handle 12 defines a lumen 48 , which extends through the length of the handle 12 . The plunger 26 is positioned within the lumen 48 of the handle 12 . The plunger 26 includes a body portion 50 having a longitudinal and radial axis and is coupled to the actuator 30 via posts 32 and 34 . The body 50 of the plunger 26 is movably disposed within the lumen 48 of the handle and can be moved along both the longitudinal and radial axis of the plunger 26 . The plunger 26 can also be biased against a spring 52 disposed about a distal end 54 of the plunger 26 within the lumen 48 of the handle 12 . The plunger 26 also includes the distal segment 28 , which extends beyond the distal end 54 of the plunger 26 and the distal end 14 of the handle 12 . The distal segment 28 of the plunger 26 is positioned between the leaves 18 and 20 of the lens inserter 10 . The distal segment 28 of the plunger 26 preferably has a thickness in a range of 100 microns to 300 microns. The plunger 26 can also include a ring 53 at the proximal end 54 of the body portion 50 of the plunger 26 . The ring 53 preferably can be formed of a material, which slides easily within the lumen 48 of the handle 12 .
[0034] FIG. 4 illustrates a perspective view of a distal end of the lens inserter apparatus 10 in accordance with an embodiment of the invention, and FIG. 5 illustrates a top view of the distal end of the lens inserter apparatus 10 shown in FIG. 4 . FIGS. 4 and 5 show the distal end 40 of the leaves 18 and 20 . The distal end 40 of each of the leaves 18 and 20 includes a generally flat lens shaped portion 42 . The lens shaped portion 42 is configured to allow a lens designed be inserted into a flap or pocket in the cornea of the eye to sit on top of the surface of the distal end 40 of the bottom leaf 20 . The distal end 40 of the leaves 18 and 20 also includes a slot 56 . The slot 56 can be configured to enable loading the lens onto the inserter 10 . Additionally, the inner surfaces of the distal end 40 of the leaves 18 and 20 sit on top of one another in order to grip the lens for insertion into the pocket or flap in the cornea.
[0035] FIG. 6 illustrates the handle 12 of the lens inserter 10 in further detail. The handle 12 includes an outer wall 46 that defines an opening 58 . The actuator 30 , not shown, can extend through the opening 58 and move within the opening 58 . The opening can be shaped such that the actuator 30 can be moved along the longitudinal axis of the plunger 26 or the radial axis of the plunger 26 . The opening 58 includes notches 60 and 62 such that the actuator 30 can be moved along the radial axis of the plunger 26 .
[0036] FIG. 7 illustrates a top view of a plunger 26 of a lens inserter 10 in accordance with an embodiment of the invention, and FIG. 8 illustrates a side view of a plunger 26 of a lens inserter 10 in accordance with an embodiment of the invention. FIGS. 7 and 8 illustrate the distal segment 28 of the plunger 26 . The distal segment 28 is generally flat and includes a fork 64 at the distal end 66 of the distal segment 28 configured to push the lens off of the lens shaped portion 42 of the leaves 18 and 20 .
[0037] FIGS. 9-11 illustrate a method of inserting a lens into a pocket or flap in a cornea in accordance with an embodiment of the invention. FIG. 9 illustrates the lens inserter 10 and a lens 66 for placement in the pocket or flap in the cornea. However, it is important to note that the lens inserter 10 can be used with any lens and packaging for the lens. Preferably, the lens 66 is approximately 2.5 mm to 3.5 mm in diameter and has an edge thickness of less than 20 microns. Although any lens suitable for insertion into a pocket or flap in a cornea can be used. As shown in FIGS. 9-11 , the lens 66 is disposed in packaging 68 . Packaging 68 includes a post 70 . As shown in FIG. 10 , the actuator 30 can be rotated about the radial axis of the plunger 26 into notches 60 and 62 of the handle 12 , in order to open the leaves 18 and 20 . As the plunger 26 is rotated it spreads the leaves 18 and 20 enough to place the bottom leaf 20 under the lens 66 . The slot 56 at the distal end 40 of the leaves 18 and 20 can slide around the post 70 of the packaging to enable grasping of the lens 66 . When the lens 66 is positioned on the lens shaped portion 42 of the bottom leaf 20 , the actuator 30 can be rotated back out of the notches 60 and 62 in order to close the leaves and grasp the lens.
[0038] FIG. 12 illustrates a method of inserting a lens into a pocket or flap in a cornea in accordance with an embodiment of the invention. Step 100 shows the distal end 40 of the leaves 18 and 20 grasping the lens 66 , and a pocket 72 in the cornea 74 of the eye 76 . Step 110 shows the lens inserter 10 inserted into the pocket 72 . Step 120 shows the plunger 26 being advanced to push the lens 66 off of the leaves 18 and 20 . Additionally, step 130 shows the lens 66 placed in the eye 76 and the lens inserter 10 being removed from the eye 76 .
[0039] The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention, which fall within the true spirit, and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A method for inserting a lens into a corneal pocket or flap includes providing a lens inserter device, opening a first leaf and a second leaf of the device, positioning a slot of each one of a first and a second lens shaped portion over a post on a packaging of the lens, positioning the lens between the first leaf and the second leaf, inserting the lens into the corneal pocket, and releasing the lens from the lens inserter device. | 0 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to a ventilation hood with a safety system for use with a cooktop. More particularly, the invention relates to a ventilation hood with a safety system designed to substantially reduce the possibility of a fire occurring in the ventilation hood and ductwork thereof, as well as reducing humidity resulting from steam generated by the operation of the cooktop. The invention further relates to a combination of a ventilation hood and cooktop system, as well as a method of operation of a ventilation hood and a cooktop.
[0002] A number of ventilation hood control units are known for reducing the spread of smoke resulting from cooking operations on cooktops, as well as for removing humidity caused by steam resulting from cooking on the cooktop.
[0003] One known system provides a control or regulating device for a stove which activates, deactivates, controls and regulates the heat energy of cooking zones of the stove in dependence upon the resulting cooking steam. The control device and corresponding sensor of such a system is installed in the ventilation hood associated with the stove. Such a system is primarily focused on controlling the level of steam detected, to control operation of the cooking zones and not the ventilation fan. The makers of the system list as one of its advantages achieving a substantial savings of energy.
[0004] Another prior art system proposes a smart circuit device for a smoke exhauster for cooking. The circuit device includes a sensing circuit for sensing temperature and smoke. The motor of the fan and the exhauster is controlled to operate at a rotation speed conducive to reducing noise and save energy. The fan speed is varied in response to the quantity of smoke and is controlled by a fuzzy logic controller.
[0005] Yet still another system for a commercial or institutional kitchen provides that the volume rate of a cooking exhaust may be increased to improve the general comfort, health and safety conditions in the kitchen and the rest of the facility. More particularly, such a system senses a parameter in the ambient air environment such as temperature and/or gas level. Depending on the activity of the cooking units, the air control system causes the exhaust system to increase the volume rate to a higher volume rate to exhaust more air from the ambient air environment, thereby reducing the temperature in the facility to improve comfort and reduce load on an high volume air conditioning (HVAC) system.
[0006] While all of these systems provide advantages in reducing ambient smoke and/or steam for the purpose of providing a comfortable environment for persons using a cooktop, these conventional systems still fall short in providing an optimized arrangement designed to minimize fires occurring in ventilation hoods and cooktops.
[0007] More particularly, the use of cooktops in an incorrect manner contrary to a manufacturer's instructions can cause a fire. Many current gas cooktops have burners which can operate at energy levels of greater than 15,000 BTUs. Such cooktops include four to six burners and the simultaneous operation of multiple ones of these burners for a long period of time can overheat ventilation elements exhaust ducts.
[0008] The overheating of ventilation elements exhaust ducts is particularly of concern in circumstances in which such ventilation hoods and elements in ducts have accumulated oils and fat in the duct tubes thereof as such oils and fats are entrained with gases and/or vapors being drawn through the ventilation hood duct during cooking operations. If the heat conditions above the cooktop exceeds certain parameters such as may occur, for example, as a result of a flame, or through use of many of the high BTU burners at one time, a substantial portion of the heat generated may be drawn into the duct system and cause a fire as a result of, among other reasons, the ignition of the oils or fat accumulated in the duct tubes.
[0009] In accordance with the invention, there is provided a ventilation hood with a safety system, a combination of a ventilation hood with a cooktop and a method of controlling operation of a ventilation hood and cooktop, which avoids the problems of the previously discussed conventional systems, and which substantially reduces or eliminates the danger of fire occurring in the duct work of the ventilation hood as a result of operation of the cooktop.
BRIEF SUMMARY OF THE INVENTION
[0010] In accordance with one aspect of the invention, there is provided a ventilation hood with a safety system for use with a cooktop. The hood includes a duct structure for having air flow through the duct structure. A variable speed fan is associated with the duct structure for forcing air to flow from above the cooktop through the duct structure. A temperature sensor serves to sense the temperature above the cooktop and an alarming unit serves to provide at least one type of alarming indication. A controller unit is associated with the aforementioned elements for controlling operation of the fan and the alarming unit. The controller unit is configured for increasing the speed of the fan when in operation, and for activating the alarming unit to provide a first alarm indication upon the temperature above the cooktop reaching a first predetermined level, and for causing the alarming unit to provide a second alarm indication upon the temperature above the cooktop reaching a second (higher) predetermined temperature.
[0011] In accordance with one aspect of the present invention, the controller unit is also connected to a cooktop for controlling operation thereof. The controller unit is further programmed for causing the alarming unit to provide a third alarm indication upon the temperature above the cooktop reaching a third predetermined temperature and for shutting down the fan and the cooktop.
[0012] A method of operating a ventilation hood used with a cooktop includes providing a ventilation hood having a duct structure for having airflow therethrough. A temperature sensor is provided and serves to sense temperature above the cooktop. An alarming unit is also provided and serves to provide at least one type of alarm indication. A controller unit is provided which serves to control operation of the fan and alarming unit. The method involves sensing the temperature above the cooktop, increasing the speed of the fan and providing a first alarm indication upon the sensed temperature reaching a first predetermined level. A second alarm indication is provided upon the sensed temperature reaching a second predetermined (higher) level.
[0013] In accordance with a further aspect of the present invention, the controller unit is connected to a cooktop associated with the hood. The method further involves shutting off the cooktop and fan and providing a third alarm indication upon the sensed temperature reaching a third predetermined (even higher) level.
[0014] In accordance with yet another aspect of the present invention, the invention involves a combination of a ventilation hood and a cooktop including the features of the previously described ventilation hood as connected to the cooktop for controlling operation of the cooktop and the ventilation hood.
BRIEF DESCRIPTION OF THE DRAWING
[0015] FIG. 1 is a front elevational view in partial section of a ventilation hood safety system connected to a freestanding range that comprises a cooktop, and showing the various elements of the present invention; and
[0016] FIG. 2 is a temperature status table illustrating the various operating states of the system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] In accordance with the present invention, there is provided a ventilation hood 11 that includes a duct structure 13 and a variable speed fan 15 with a variable speed motor 17 and a plurality of associated fan blades 19 . The hood 11 also includes a temperature or heat sensor 21 and a steam or humidity sensor 23 , both connected to a controller unit 25 . Associated with the ventilation hood 11 is a free standing range 27 including an oven 29 , cooktop 31 including a plurality of burners 33 , and controls 35 for controlling operation of the oven 29 and the burners 33 . Also associated with the freestanding range 27 is an alarming unit including an alarm indicator 36 and an automatic control module 37 , which, along with the temperature sensor 21 and the humidity sensor 23 , is connected to the controller unit 25 .
[0018] The operation of the ventilation hood 11 and the cooktop 31 will hereinafter be described with reference to the temperature status table set forth in FIG. 2 in accordance with which the system, including the controller unit 25 and the module 37 , is programmed. Although the system of the present invention is described as being implemented via software programming, the same function can be provided by the appropriate hardware, as will be readily apparent to those of ordinary skill in the art. Such programming may be done in numerous ways through firmware, downloadable software, and other means as also will be readily apparent to those of skill in the art.
[0019] When at least one of the burners 33 of the cooktop 31 is turned on through the use of the controls 35 , the automatic control module 37 provides feedback to the controller unit 25 , whereupon the controller unit 25 activates the fan motor 17 to cause blades 19 of the fan 15 to rotate at a first normal operating speed. If the temperature above the cooktop 31 reaches a first predetermined level, as detected by the temperature sensor 21 , the controller unit 25 causes the fan 15 to increase its speed and issues an alarm signal through the module 37 . For example, if the first predetermined level of the temperature is deemed, purely for exemplary purposes, to be a temperature of between 100 degrees Fahrenheit (=one temperature unit) to 150 degrees Fahrenheit (=one and one-half temperature units), then the controller unit 25 may be controlled to cause the fan 15 to increase its speed when a temperature at the first predetermined level of the temperature is detected.
[0020] In a typical embodiment, the alarm signal can be activation of a signal lamp in the alarm indicator 36 of the module 37 , which serves as a warning of high temperature in or in proximity to the ventilation hood 11 .
[0021] If the temperature above the cooktop 31 continues to rise to a second temperature level, as detected by the temperature sensor 21 , then the controller unit 25 causes the module 37 to issue a second alarm signal, for example, through a sound generator in the alarm indicator 36 as an audible signal. For example, if the second predetermined level of the temperature is deemed, purely for exemplary purposes, to be a temperature of between 150 degrees Fahrenheit (=one and one-half temperature units) to 200 degrees Fahrenheit (=two temperature units), then the controller unit 25 may be controlled to cause the module 37 to issue a second alarm signal when a temperature at the second predetermined level of the temperature is detected.
[0022] In an alternative aspect, the module 37 could have a visual display in the alarm indicator 36 or separately therefrom, capable of displaying text messages, and instead of an audible signal, a text message can be provided, both of which serve as a warning of an increased danger of catching fire which then allows the operator of the cooktop 31 to make decisions about continuing cooking operations.
[0023] If the temperature continues to rise to a third predetermined temperature level, as detected by the temperature sensor 21 , then the controller unit 25 issues a signal to the fan motor 17 and to the module 37 which immediately shuts down the fan motor to avoid additional heat being drawn into the duct structure 13 , and also causes the module 37 to shut down the burners 33 on the cooktop 31 . A text message is then issued on the display of the module 11 indicating that the fan 15 and the burners 33 were shut down to avoid a fire. For example, if the third predetermined level of the temperature is deemed, purely for exemplary purposes, to be a temperature of between 200 degrees Fahrenheit (=two temperature units) to 250 degrees Fahrenheit (=two and one-half temperature units), then the controller unit 25 may be controlled to issue a signal to the fan motor 17 and to the module 37 which immediately shuts down the fan motor.
[0024] In a yet still further aspect, the ventilation hood 11 also includes a humidity or steam sensor 23 , which is connected to the controller unit 25 and serves to detect steam or humidity generated from operation of the cooktop 31 . Independent of the operation of the inventive safety system with respect to temperature, if the humidity or amount of steam rises to certain levels, the controller unit is also programmed to increase the speed of the variable speed motor 17 in a predetermined relationship to the amount of steam being generated as a result of operation of the cooktop 31 . Additionally, it can be provided in this humidity reaction approach that the temperature driven controls will always take priority and will override steam/humidity driven control.
[0025] While the various elements including the temperature sensor 21 , the humidity/steam sensor 23 , the module 37 , the fan motor 17 and the controller unit 25 are shown in a hardwired configuration, it will be readily apparent to those of ordinary skill in the art that these units need not be hardwired and can operate in communication with each other through various other alternative technologies, for example, such as through infrared signals, radio signals, etc.
[0026] Yet still further, while in one specific aspect the system is shown as providing an alarm with a signal lamp for warning of reaching the first temperature level, an audible signal also can be provided. Also both audio and visual alarms can be provide at each preset warning level, which can be different in intensity or tone, as will be readily apparent to those of ordinary skill in the art. Alternatively, visible display issuing text message can be employed to provide clear information to the user of the cooktop.
[0027] Thus, the present invention provides a ventilator hood safety system having a controller unit connected to a cooktop for controlling the operation thereof, and the controller unit is further programmed for causing an alarm unit to provide a third alarm indication and for shutting down the cooktop and the fan upon the temperature above the cooktop reaching a third predetermined temperature.
[0028] The present invention additionally provides a ventilator hood safety system having a humidity sensor for sensing the humidity resulting from steam in proximity to the hood, and associated with the controller unit for having the controller unit increase the speed of the fan in response to increasing humidity. Also, the safety system includes an alarming unit including a signal lamp, and arranged for operation the controller unit for providing the first alarm indication as activation of the signal lamp. The alarming unit may include a sound generator and is arranged for operation with the controller unit for providing the second alarm indication as an audible signal generated by the sound generator. Also, the alarming unit may include a signal lamp and a visual display which are arranged for operation with the controller unit for providing the first alarm indication as activation of the signal lamp, and the second alarm indication may display a text message on the visual display warning of the danger of fire.
[0029] Having thus generally described the invention, the same will become better understood from the independent claims as set forth in a non-limiting manner. | A ventilating hood and cooktop system includes safety components to reduce or eliminate the possibility of a fire in the ventilating hood. The system provides elements for sensing the temperature over the cooktop. When the temperature reaches a first predetermined level, the ventilation fan speed is increased. The system includes alarm warning elements which issue different signals depending on the temperature above the cooktop. If a maximum temperature is reached, the system shuts off the fan of the ventilating hood and shuts down the cooktop. | 5 |
BACKGROUND OF THE INVENTION
In the graphic arts, it is desirable to produce a color proof to assist a printer in correcting a set of photomasks which will be used in exposing printing plates. The proof should reproduce the color quality that will be obtained during the printing process. The proof must be a consistent duplicate of the desired half tone or line image, and should neither gain nor lose color. Visual examination of a color proof should reveal the following characteristics:
1. Any defects on the photomask.
2. The best color rendition to be expected from press printing of the material.
3. The correct gradation of all colors and whether grays are neutral.
4. The need, if any, for subduing any of the colors and/or giving directions for altering the film photomask before making the printing plates.
Color proofing sheets for multi-colored printing have heretofore been made by using a printing press proof which requires taking all the steps necessary for actual multicolor printing. Such a conventional method of color proofing has been costly and time consuming. Alternate color proofing methods have therefore been developed to simulate the quality of press proofs. There are two known types of photographic color proofing methods, namely, the surprint type and the overlay type.
In the overlay type of color proofing, an independent transparent plastic support is used for producing an image of each color separation film. A number of such supports carrying colored images are then superimposed upon each other and placed on a white sheet to produce a color proof. The overlay type of color proofing method has the disadvantage that the superimposed plastic supports tend to darken the color proofing sheet, and, as a result, the impression of the color proofing sheet thus prepared becomes vastly different from copies actually obtained by a conventional printing press proof. Its primary advantage is that it is quick and can serve as a progressive proof by combining any two or more colors in register.
In the surprint type of color proofing method, a color proofing sheet is prepared by successively producing images of different colors from different color separation films onto a single receptor sheet. This is done by utilizing a single opaque support and by applying toners, photosensitive solutions or coatings of photosensitive materials of corresponding colors on the opaque support in succession. An example of this approach is described in U.S. Pat. No. 3,671,236. An advantage of the surprint type of color proof is that the color saturation is not influenced by superimposed plastic supports. This method more closely resembles the actual printing and eliminates the color distortion inherent in the overlay system.
Various processes for producing copies of an image embodying photopolymerization and thermal transfer techniques are known as shown in U.S. Pat. Nos. 3,060,023; 3,060,024; 3,060,025; 3,481,736; and 3,607,264. In these processes, a photopolymerizable layer coated on a suitable support is imagewise exposed to a photographic transparency. The surface of the exposed layer is then pressed into contact with the image receptive surface of a separate element and at least one of the elements is heated to a temperature above the transfer temperature of the unexposed portions of the layer. The two elements are then separated, whereby the thermally transferrable, unexposed, image areas of the composite transfer to the image receptive element. If the element is not precolored, the tacky unexposed image may now be selectively colored with a desired toner. The colored matter preferentially adheres to the clear unpolymerized material. U.S. Pat. No. 3,574,049 provides a transfer process for printing a design on a final support which comprises (a) printing a design onto a temporary support, (b) superimposing the temporary support and the final support, (c) applying heat and/or pressure to the superimposed structure formed in (b), and (d) separating the temporary support from the final support which retains the printed design. The affinity of the design for the temporary support is lower than its affinity for the final support.
In U.S. Pat. No. 3,721,557 a method of transferring colored images is claimed which provides a stripping layer coated between the photosensitive element and the support. When the photosensitive layer is exposed to actinic light and developed, the more soluble portions are selectively removed to produce a visible image. The image-carrying support is pressed against a suitable adhesive coated receptor and, subsequently, the carrier support sheet is stripped to accomplish the transfer of the image. A fresh layer of adhesive is applied to the receptor for each subsequent transfer.
U.S. Pat. Nos. 4,260,673 and 4,093,464 describe positive working one-piece proofing systems based on orthoquinone diazides. In U.S. Pat. 4,093,464 a colored image is transferred to a receiver sheet after exposure and development. U.S. Pat. 4,260,673 describes transfer of a solid color layer to a receiver sheet prior to exposure and development. U.S. Pat. No. 4,659,642 teaches a positive working color proofing system which has a transparent substrate, a colored photosensitive layer on the substrate, and a top adhesive layer. The present invention improves upon the foregoing by incorporating an improved positive working color proofing film comprising a poly(vinyl acetal/vinyl alcohol/vinyl acetate) terpolymer in the photosensitive layer.
SUMMARY OF THE INVENTION
The present invention provides an improved method for forming a colored image which comprises:
A. providing a photosensitive element which comprises, in order:
(i) a substrate having a release surface; and
(ii) a photosensitive layer on said release surface, which photosensitive layer comprises a light sensitive, positive working, naphthoquinone diazide compound; a resinous binder composition, which composition contains at least 20% of a resin having the general formula
--A--B--C--
wherein a plurality of each of components A, B and C occur in ordered or random sequence in the resin and wherein A is present in said resin at about 5% to about 20% by weight and comprises groups of the formula ##STR1## B is present in said resin at about 4% to about 30% by weight and comprises groups of the formula ##STR2## and C is present in said resin at about 50% to about 91% by weight and comprises acetal groups consisting of groups of the formulae ##STR3## where R is lower alkyl or hydrogen, and wherein said group I. is present in component C from about 75% to about 85%; group II. is present in component C from about 3% to about 5%; and group III. is present in component C from about 10% to about 22%; wherein all acetals are based on the mol number of components (C) and at least one colorant; and
(iii) an adhesive layer in direct contact with said photosensitive layer, which adhesive layer comprises a polyvinyl acetate polymer and which adhesive layer is nontacky at room temperature, thermally activated and can be transferred at temperatures between 60° C. and 90° C.; and
B. either
(i) laminating said element with heat and pressure via said adhesive layer to a developer resistant receiver sheet; and removing said substrate by the application of peeling forces; and imagewise exposing said photosensitive layer to actinic radiation; or
(ii) imagewise exposing said photosensitive layer to actinic radiation; and laminating said element with heat and pressure via said adhesive layer to a developer resistant receiver sheet; and removing said substrate by the application of peeling forces; or
(iii) laminating said element with heat and pressure via said adhesive layer to a developer resistant receiver sheet; and imagewise exposing said photosensitive layer to actinic radiation; and removing said substrate by the application of peeling forces; and
C. removing the exposed areas of said photosensitive layer with a suitable liquid developer, which removing is conducted at a temperature at which said adhesive layer is substantially non-tacky; and preferably
D. repeating steps A through C at least once whereby another photosensitive element having at least one different colorant is laminated onto said receptor sheet over the non-removed portions of the previously laminated photosensitive layer or layers.
The invention also comprises the above described photosensitive element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In carrying out the method of the invention, one employs a photographic element which broadly comprises a substrate having a release surface, a colored photosensitive layer on the release surface and an adhesive layer on the photosensitive layer. Optional additional layers containing anti-halation materials, adhesion promoters or release agents may also be used.
In the preferred embodiment, the substrate is composed of a dimensionally and chemically stable base material which does not significantly change its size, shape, or chemical properties as the result of the heating, coating or other treatments which it must undergo. One preferred material is polyethylene terephthalate. In the usual case it has a thickness of from about 1 to about 10 mils, a more preferred thickness is from about 2-5 mils and most preferably from about 2-3 mils. Suitable films include Hostaphan 3000, available from Hoechst Celanese Corporation, Mylar D, available from DuPont and Melinex grades 0; 052; 442; 516 and S, available from ICI. The surface of the substrate may be smooth or may be provided with a matte texture by various methods known in the art.
Matte films include Melinex 377 and 470 from ICI. These materials have the unique property of giving the final image a desired matte finish without any extra steps. One can control the gloss of the final image by properly selecting the matte finish of the temporary support. This effect works because the top layer of the final image is originally in contact with this matte surface. This does not occur with a separate release layer between the temporary support and photosensitive layer. An additional advantage of coating on a matte surface is that subsequent transferred layers generally adhere better to a rough surface than to a smooth surface.
A similar matte finish of the final image can be obtained by embossing the shiny, top surface of the image with a matte material, such as described above. This is done by laminating together the final image and matte material under pressure and temperature. The matte material is then generally removed after lamination. The advantage of this method is that the finish of the final proof can be varied. Furthermore, the matting material can be used repeatedly.
A third method for producing a matte finish uses a heat transferable layer, such as Butvar 90, available from Monsanto, coated onto a film with a rough surface, such as Melinex 329, available from ICI. The transferable layer is laminated to the final image under pressure and temperature. Then the film with the rough surface is peeled off. The rough surface of the transferred layer imparts a matte finish to the final image. The advantage is that all layers appear matte and that the extra transferred layer protects the image. U.S. Pat. Nos. 4,294,909 and 4,376,159, also suggests various methods for making a matte surface.
In either case, the substrate must have a release surface, that is, it must be capable of releasably holding the photosensitive layer thereto. This may be accomplished either by the substrate surface being inherently releasable, being rendered releasable by a suitable treatment or being provided with a release layer over the substrate surface. Such a release layer may comprise polyvinyl alcohol.
Releasably bonded to the release surface is the photosensitive layer. The photosensitive layer broadly comprises a photosensitizer, colorants, binding resins, and other optional ingredients such as plasticizers, acid stabilizers, surfactants, antistatic compositions, uv absorbers and residual coating solvents.
The preferred photosensitizer is a light sensitive, naphthoquinone diazide. The most preferred photosensitizer is the ester of bis-(3-benzoyl-4,5,6 trihydroxy phenyl)-methane and 2-diazo-1-naphthol-5-sulfonic acid as taught in the U.S. Pat. No. 4,407,926. Other suitable photosensitizers are taught in the U.S. Pat. Nos. 4,266,001, 3,106,365, 3,148,983 and 3,201,239. The diazo compounds of choice are preferably soluble in organic solvents.
Suitable binding resins have the general formula
--A--B--C--
wherein a plurality of each of components A, B and C occur in ordered or random sequence in the resin and wherein A is present in said resin at about 5% to about 20% by weight and comprises groups of the formula ##STR4## B is present in said resin at about 4% to about 30% by weight and comprises groups of the formula ##STR5## and C is present in said resin at about 50% to about 91% by weight and comprises acetal groups consisting of groups of the formulae ##STR6## where R is lower alkyl or hydrogen, and wherein said group I. is present in component C from about 75% to about 85%; group II. is present in component C from about 3% to about 5%; and group III. is present in component C from about 10% to about 22%. All of said acetal members are based on the mol number of acetal units in component C. An important resin selection criterion is that it must be a good firm former.
These resins are more fully described in U.S. Pat. No. 4,665,124 which is incorporated herein by reference.
The colorants useful for the present invention include various classes of dyes and pigments. In the most preferred embodiment, pigments having an average particle size diameter of about 1 micrometer or less are used.
Optional plasticizers which may be incorporated into the photosensitive layer include those of the phthalate and phosphate types. Preferred plasticizers include dibutyl phthalate and dimethyl phthalate. Polymeric plasticizers include acrylic resins such as Carboset 525 available from BF Goodrich. Developing aids include polymers with acid groups such as Carboset XL27 available from BF Goodrich, Scripset 540 available from Monsanto and Elvacite 2028 available from DuPont.
These ingredients may be blended with such compatible solvents as gamma butyrolactone, diacetone alcohol, propylene glycol monomethyl ether, ethanol, methyl cellosolve and methyl ethyl ketone, coated on the release surface, and dried. In the preferred embodiment, the photosensitive layer has a coating weight between approximately 0.1 and 5.0 g/m 2 . The most preferred weight is from about 0.4 to 2.0 g/m 2 .
In the preferred embodiment, the photosensitizer is present in the photosensitive layer in an amount of from about 15 to about 60 percent by weight; or more preferably from about 20 to about 50 percent by weight.
In the preferred embodiment, the colorant is present in the photosensitive layer in an amount of from about 10 to about 40 percent by weight; or more preferably from about 13 to about 34 percent by weight.
In the preferred embodiment, the binding resin is present in the photosensitive layer in an amount of from about 20 to about 75 parts by weight; or more preferably from about 30 to about 70 parts by weight.
In the preferred embodiment, the plasticizer, when one is used, is present in the photosensitive layer in an amount of up to about 20 parts by weight; or more preferably up to about 15 parts by weight and most preferably from about 12 to about 15 parts by weight.
Typical formulations for the photosensitive layer include:
______________________________________ Yellow Magenta Cyan Black______________________________________propylene glycol monomethyl 57.00 50.40 33.72 43.44ethermethyl ethyl ketone 9.37 10.72 34.22 25.20gamma-butryolactone 19.35 22.53 16.96 15.33diacetone alcohol 9.72 11.12 9.40 11.09polyvinyl acetal/alcohol/ 0.82 0.88 1.04 0.73acetate resin in example #1Butvar B-90 0.36 0.41 0.45 0.42Scripset 550 1.20 1.19 1.20 --Scripset 540 -- -- -- 1.41Above diazo from U.S. 1.50 1.87 1.78 1.494,407,926phthalo blue pigment -- 0.01 1.23 --yellow pigment 0.68 0.02 -- --magenta pigment -- 0.85 -- --black pigment -- -- -- 0.89______________________________________
The adhesive layer comprises polyvinyl acetate and may optionally contain such other desired components as uv absorbers, optical brighteners, anti-static compositions and plasticizers. Useful polyvinyl acetates non-exclusively include Mowilith DM-6, 20, DM-22, 25, 30 and mixtures thereof, available from Hoechst AG. These are usually dispersed in water, or dissolved in methyl isobutyl ketone or n-butyl acetate or other solvent compositions for coating on the photosensitive layer. It is then dried to a coating weight of from about 5 to about 30 g/m 2 , more preferably from about 10 to about 20g/m 2 . The layer may optionally contain a uv absorber such as Uvinul D-50 from G.A.F. It may also contain a polymeric plasticizer such as Resoflex R-296, a polyester plasticizer available from Cambridge Industries or Carboset 525 available from BF Goodrich. It ma also contain antistats, such as Gafac and Gafstat from G.A.F. It may also contain other resins, such as Nitrocellulose RS 1/2, available from Hercules. It may also contain an optical brightener such as Uvitex OB from Ciba Geigy. The adhesive layer should not be tacky to the touch, during storage or during development of the photosensitive element. The layer should have a softening point in the range of from about 60° C. to about 180° C., preferably 60° C. to 120° C., more preferably 60° C. to 100° C. In the preferred embodiment, the polyvinyl acetate is present in the adhesive layer in an amount of greater than about 50 percent by weight. The plasticizer may be present in an amount of up to about 30 percent by weight, the uv absorber up to about 20 percent by weight, the optical brightener up to 1.0 percent by weight, and other resins up to about 50 percent by weight.
Typical adhesive formulations include:
______________________________________I. Water 50.00 Mowilith DM-22 50.00II. i-butyl acetate 78.00 Resoflex 1.00 Mowilith 30 21.00III. i-butyl acetate 79.90 Uvitex OB 0.10 Mowilith 30 20.00______________________________________
In operation, the photosensitive element is laminated to a receptor sheet via the adhesive layer. The receiver sheet should be resistant to any adverse effects which may be caused by the developer of choice. For example, the receiver sheet should be water resistant if aqueous developers are used. Plastic or plastic-coated receiver sheets are useful for this purpose.
Useful receiver sheets include Melinex 329; 339; 994 and 3020 from ICI. Other white and nonwhite receiver sheets may also be used. Rough textured and/or adhesion promoted surfaces are preferred for the receiver, which must be able to withstand the laminating and development processes.
Lamination may be conducted by putting the receiver sheet in contact with the adhesive side of the colored composite and then introducing the two materials into the nip of a pair of heated laminating rollers under suitable pressure. Suitable laminating temperatures usually range from about 60° C. to about 90° C., preferably about 75° C. to about 85° C.. After lamination, the substrate is peeled away, usually merely employing manual peeling forces. The adhesive and photosensitive layers thus remain on the receiver sheet.
The photosensitive layer is imagewise exposed by means well known in the art either before or after lamination. Such exposure may be conducted by exposure to a uv light source through a photomask under vacuum frame conditions. Exposure may be performed with actinic light through a conventional positive flat. Exposures after lamination and peel apart are preferred for emulsion-to-emulsion contact. Mercury vapor discharge lamps are preferred over metal halide lamps. Filters may be used to reduce light scattering in the material.
After lamination, peel apart and exposure, the photosensitive layer is developed by dissolving the exposed area in a suitable developer and dried. A suitable developer useful for developing a lithographic printing plate made with the resin of the present invention includes an aqueous solution containing one or more of the following groups:
(a) a sodium, potassium or lithium salt of octyl, decyl, dodecyl, or tetradecyl monosulfate;
(b) a sodium, lithium, potassium or ammonium metasilicate salt,
(c) a lithium, potassium, sodium or ammonium borate salt;
(d) an aliphatic dicarboxylic acid, or sodium, potassium or ammonium salt thereof having from 2 to 6 carbon atoms; and
(e) mono, di-, or tri-sodium or potassium phosphate.
Other suitable developers include water, benzoic acid or sodium, lithium and potassium benzoates and hydroxy substituted analogs thereof as well as those developers desribed in U.S. Pat. No. 4,436,807. The adhesive layer is not substantially removed by this development. Specific examples of suitable developers non-exclusively include
______________________________________I.Water 95.0Sodium decyl sulphate 3.0Disodium phosphate 1.5Sodium metasilicate 0.5II.Water 89.264Monosodium phosphate 0.269Trisodium phosphate 2.230Sodium tetradecyl sulfate 8.237______________________________________
Any developer solution which satisfactorily removes the exposed areas of the photosensitive layer after exposure while retaining the image areas may be used. The selection of developer is well within the ability of the skilled artisan.
The process can then be repeated whereby another photosensitive element having a different color is laminated to the same receiver sheet over the previously formed image. In the usual case, four colored layers are employed to produce a full color reproduction of a desired image. These are cyan, magenta, yellow and black.
The following non-limiting example serves to illustrate the invention.
EXAMPLE
The resin is made from a copolymer of polyvinyl alcohol/polyvinyl acetate, Vinol 523. 75.0G of Vinol 523 which has from about 75% to 80% hydroxyl groups by weight and an average molecular weight of about 70,000, is dissolved in a solution comprising 225.0 g of water and 200.0 g of ethanol for 16 hours at 70° C. after which 10.13 of hydrochloric acid (37%) is added and the temperature adjusted to 60° C. while mixing vigorously. 37.66 g of propionaldehyde is slowly titrated into the reaction mixture. Simultaneously, 250.0 g of ethanol is likewise titrated into the reaction mixture. The mixture is then neutralized to a pH of 7.0 with a sodium carbonate/sodium hydroxide (50/50) mixture. The product is isolated in granular form by precipitation with water. It is then dried so as to have a moisture residue of not greater than 1.0%. A yield of 107 g or about 96% is obtained. The average molecular weight is about 90,000.
Using standard analytical techniques, the product is found to consist of 13.6% acetate, 9.85% hydroxyl, and 76.6% acetal groups. Of the acetal groups, 80% are found to be six-membered cyclic acetal, 4% are five-membered cyclic acetal, and 16% are intermolecular acetals.
Four photosensitive solutions of cyan, yellow, magenta, and black are produced according to the photosensitive formulations described above. The pigment is introduced as a dispersion of the above polyvinyl acetal/alcohol/acetate resin and the appropriate pigment in a 1:1 solvent mixture of gamma butryolactone and propylene glycol monomethyl ether. The pigment and resin loading in the dispersions are as follows:
______________________________________ Cyan Yellow Magenta Black______________________________________Pigment 6.5% 5.0% 5.2% 5.5%Binder 5.5% 6.0% 5.2% 4.5%______________________________________
The solutions are coated and dried separately to the required optical density onto 3 mil Melinex 516 polyester films as temporary support. The surface densities are roughly 0.8 g/m 2 for cyan, 0.9 g/m 2 for yellow, 1.0 g/m 2 for magenta, and 1.3g/m2 for black. The adhesive solution, in particular adhesive formulation number II from above, is coated on top of the photosensitive layers and dried to an surface density of 12 g/m 2 . The yellow composite is then laminated at 80° C. with the adhesive side onto either side of a 7 mil Melinex 3020 polyester receiver sheet. The 516 temporary support is peeled away after lamination, leaving the adhesive and photosensitive layers on the receiver sheet. The yellow photosensitive layer is then exposed to actinic light through a photographic flat for the yellow color. The receiver sheet with the exposed yellow layer is then immersed for 15 sec in developer II from above at 27° C. with gentle pad rubbing on the photosensitive side. The exposed yellow areas are thereby washed off and the nonexposed areas remain during development. The adhesive layer is not effected by the developer. After this treatment, the imaged material is rinsed and then dried. The magenta composite is then laminated as before onto the imaged, yellow side of the receptor sheet. The temporary support is removed as before. The magenta layer is then exposed through the magenta flat. It is then processed as with the yellow. The magenta is followed in a like manner by cyan and then by black to give a four color image which is an accurate representation of the original from which separations are prepared. | This invention relates to positive working photosensitized sheet constructions which, upon exposure to an actinic radiation source through a screened image, can accurately reproduce said image. The construction is useful as a color proofing film which can be employed to predict the image quality from a lithographic printing process. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS AND CLAIM OF PRIORITY
This patent application claims benefit under 35 U.S.C. 119(e), 120, 121, or 365(c), and is a National Stage entry from International Application No. PCT/KR2012/000754, filed 31 Jan. 2012, which claims priority to Korean Patent Application No. 10-2011-0096271, filed 23 Sep. 2011, entire contents of which are incorporated herein by reference.
BACKGROUND
1. Technical Field
The present invention relates to a composition for an antifreeze or a coolant, including: (a) a glycol-based anti-freezing agent; (b) cyclohexane dicarboxylic acid; and (c) non-reducing polyol.
2. Background Art
Generally, a composition for an antifreeze or a coolant mainly consists of ethylene glycol or propylene glycol. The composition contains, as main components, a carboxylic additive and an organic material, in order to prevent corrosions of aluminum- and iron-based parts. A water pump is used to circulate a cooling water in a cooling system. Here, cavitation erosion due to metal erosion may occur on an impeller of the water pump, which rotates at high speed/high temperature. Moreover, a coolant tends to infiltrate into a gap between a non-metal material and a metal material, which is generated when a line made of a non-metal material such as rubber or plastic is coupled with a line made of a metal material in the cooling system, and a narrow gap inside the cooling system, thereby accelerating gap corrosion therebetween. Since only the combination of aliphatic and aromatic carboxylic acids had a little effect in preventing cavitation erosion and gap corrosion in the vehicle engine cooling system, non-reducing polyol was further used.
U.S. Pat. No. 4,869,841 discloses that, in order to improve overall anti-corrosive performance on alloy and metal parts as heat transfer media, aliphatic dicarboxylic acid and polyol are used to enhance the anti-corrosive performance on metal materials through the ASTM D 1384 metal corrosion test, but fails to disclose anti-corrosive performance against cavitation erosion and gap corrosion. An anti-corrosive composition for anti-corrosion against cavitation erosion and gap corrosion, which occur in a circulation procedure at high speed in the cooling system, has been requested.
Throughout the entire specification, many patent documents are referenced and their citations are represented. The disclosures of cited patent documents are entirely incorporated by reference into the present specification, and the level of the technical field within which the present invention falls and details of the present invention are explained more clearly.
SUMMARY
The present inventors endeavored to develop an antifreeze or a coolant for enhancing the anti-corrosive performance against cavitation erosion- and gap corrosion. As a result, the present inventors established that a combination of cyclohexane dicarboxylic acid and non-reducing polyol in the composition contained in an antifreeze or a coolant exhibits superior effects in preventing corrosion of metal parts, cavitation erosion, and gap corrosion in a cooling system for a vehicle, and then completed the present invention.
Accordingly, an aspect of the present invention is to provide a composition for an antifreeze or a coolant.
Other purposes and advantages of the present disclosure will become clarified by the following detailed description of invention, claims, and drawings.
In accordance with an aspect of the present invention, there is provided a composition for an antifreeze or a coolant, the composition including: (a) a glycol-based anti-freezing agent; (b) cyclohexane dicarboxylic acid; and (c) non-reducing polyol.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts images showing appearances of water pumps after the cavitation erosion test for Examples 1 to 5 and Comparative Example 2.
FIG. 2 depicts digital microscopic images showing gap corrosion of aluminum castings after the gap corrosion test for Examples 1 and 2 and Comparative Examples 1 and 2.
DETAILED DESCRIPTION
The present inventors endeavored to develop an antifreeze or a coolant for enhancing the anti-corrosive performance against cavitation erosion and gap corrosion. As a result, the present inventors established that a combination of cyclohexane dicarboxylic acid and non-reducing polyol in the composition contained in an antifreeze or a coolant exhibits superior effects in preventing corrosion of metal parts, cavitation erosion, and gap corrosion in a cooling system for a vehicle.
The composition of the present invention includes: (a) a glycol-based anti-freezing agent; (b) cyclohexane dicarboxylic acid; and (c) non-reducing polyol. The contents of the components used in the present invention are not particularly limited. Preferably, the composition includes 85-98 wt % of the glycol-based anti-freezing agent, 0.1-13.0 wt % (more preferably, 0.1-6.0 wt %) of the cyclohexane dicarboxylic acid, and 0.05-2.0 wt % of the non-reducing polyol.
The composition of the present invention generally contains glycol used as an anti-freezing agent. The glycol serves to prevent the freezing and bursting of engines and cooling systems, and includes one or a mixture of two or more selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, glycerin, triethylene glycol, tripropylene glycol, 1,3-butylene glycol, and hexylene glycol. The use content of the glycol is preferably 85-98 wt %. Less than 85 wt % of the glycol may cause the freezing and bursting of engines and cooling systems at sub-zero temperatures in the winter, and may cause the boiling of the coolant in the engines at high outdoor temperatures in the summer. On the other hand, more than 98 wt % of the glycol may cause a scarcity of anti-corrosive agent, resulting in a difficulty in performing the long-term anti-corrosive capability.
According to a preferable embodiment of the present invention, the composition of the present invention further includes at least one anti-corrosive agent selected from the group consisting of C 4 -C 18 organic carboxylic acids and alkali salts thereof, phosphoric acid and phosphates thereof, azole derivatives and thiazole derivatives, and barium and barium compounds.
The use content of the anti-corrosive agent is not particularly limited, but preferably 1-20 parts by weight based on 100 parts by weight of the glycol-based anti-freezing agent.
The C 4 -C 18 organic carboxylic acid or alkali salt thereof used in the composition of the present invention is: at least one selected from the group consisting of adipic acid, suberic acid, glutaric acid, neodecanoic acid, neooctanoic acid, succinic acid, cinnamic acid, azelaic acid, methyl cinnamic acid, hydroxy cinnamic acid, cinnamic acid ethyl, propyl cinnamic acid, butyl cinnamic acid, ethoxy cinnamic acid, ethyl benzoic acid, propyl benzoic acid, pimelic acid, dicyclopentadiene dicarboxylic acid, undecanoic acid, benzoic acid, nonanoic acid, phthalic acid, decanoic acid, terephthalic acid, dodecanoic acid, methyl benzoic acid, hexanoic acid, cyclohexenoic acid, 2-ethylhexanoic acid, sebacic acid, decane dicarboxylic acid, t-butyl benzoic acid, octanoic acid, and heptanoic acid; more preferably at least one selected from the group consisting of succinic acid, cinnamic acid, benzoic acid, 2-ethylhexanoic acid, sebacic acid, decane dicarboxylic acid, and t-butyl benzoic acid; and most preferably at least one selected from the group consisting of sebacic acid, decane dicarboxylic acid, and t-butyl benzoic acid.
The phosphoric acid or phosphate thereof used in the composition of the present invention is: phosphoric acid, ortho-phosphoric acid, sodium phosphate, potassium phosphate, sodium monohydrogen phosphate, potassium monohydrogen phosphate, sodium dihydrogen phosphate, or potassium dihydrogen phosphate; more preferably phosphoric acid, sodium phosphate, or potassium phosphate; and most preferably phosphoric acid.
The azole or thiazole derivative used as an anti-corrosive agent on copper or brass in the composition of the present invention exhibits anti-corrosive capability on copper alloy parts inside the cooling system. Here, the azole or thiazole derivative is: one or a mixture of two or more selected from the group consisting of tolyltriazole, benzotriazole, 4-phenyl-1,2,3-triazole, 2-naphthotriazole, 4-nitrobenzotriazole, and 2-mercaptobenzotriazole; and preferably one or a mixture of two or more selected from the group consisting of tolyltriazole and benzotriazole.
The barium or barium compound used in the composition of the present invention is preferably one or a mixture of two or more selected from the group consisting of barium, barium chloride, barium hydroxide, barium nitrate, barium carbonate, barium acetate, barium sulfate, barium bromate, barium thiocyanate, barium titanate, barium fluoride, barium cyanate, barium benzene sulfonate, barium bromide.
According to a preferable embodiment of the present invention, the cyclohexane dicarboxylic acid used as an anti-corrosive agent on aluminum- and iron-based parts in the composition of the present invention serves to protect various kinds of metallic parts inside the cooling system against corrosion for a long time. Here, one or a mixture of two or more selected from the group consisting of 1,4-cyclohexane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid, and 1,2-cyclohexane dicarboxylic acid may be used. The use content of the cyclohexane dicarboxylic acid contained in the composition of the present invention is preferably 0.1-13.0 wt %, and more preferably 0.1-6.0 wt %. If the content of the cyclohexane dicarboxylic acid is less than 0.1 wt %, such a small content cannot give an expectation of sufficient anti-corrosive effects on the aluminum- and iron-based parts. If the content of the cyclohexane dicarboxylic acid is more than 13.0 wt %, such an excessive content may cause a deterioration in the liquid stability, an excessive time for dissolution, and a decrease in economic feasibility.
According to a preferable embodiment of the present invention, the non-reducing polyol used in the composition of the present invention includes sorbitol, xylitol, mannitol, or saccharose. As used herein, the term “polyol” means sugar alcohol of CH 2 OH—(CHOH) n —CH 2 OH and its anhydride dimer. The non-reducing polyol used in the composition of the present invention is selected from hexitol having six carbon atoms, e.g., sorbitol and mannitol; pentatol having five carbon atoms, e.g., xylitol; and polymeric alcohol having 12 carbon atoms, e.g., saccharose. Most preferably, one or a mixture of two or more selected from the group consisting of mannitol, sorbitol, and xylitol may be used. The use content of the non-reducing polyol is preferably 0.05-2.0 wt %. If the content of the non-reducing polyol is less than 0.05 wt %, such a small content cannot give an expectation of sufficient anti-corrosive effects against cavitation erosion and gap corrosion. If the content of the non-reducing polyol is more than 2.0 wt %, such an excessive content may cause a deterioration in the liquid stability and induce cavitation erosion and gap corrosion, thereby having an adverse effect in the long-term corrosion prevention.
The composition for an antifreeze or a coolant of the present invention may further include a pH adjuster, a dye, or a defoaming agent. The pH adjuster may include alkali metal hydroxide, and may be preferably potassium hydroxide or sodium hydroxide.
As described above, the main characteristic of the present invention is to provide an antifreeze or a coolant having excellent effects in preventing corrosion of metal parts, cavitation erosion, and gap corrosion in the cooling system for a vehicle, by combining cyclohexane dicarboxylic acid and non-reducing polyol.
Features and advantages of the present invention are summarized as follows:
(a) The present invention provides a composition for an antifreeze or a coolant, the composition including cyclohexane dicarboxylic acid, and, as an additive, non-reducing polyol.
(b) The combination of mono- or di-carboxylic acid used as an anti-corrosive agent with an inorganic additive may generally cause cavitation erosion and gap corrosion. However, the combination of cyclohexane dicarboxylic acid and non-reducing polyol in the composition leads to a synergy effect thereof, thereby having excellent effects in preventing cavitation erosion and gap corrosion in the cooling system due to a synergic effect thereof.
Hereinafter, the present invention will be described in detail with reference to examples. These examples are only for illustrating the present invention more specifically, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples.
EXAMPLES
Throughout the present specification, the term “%” used to express the concentration of a specific material, unless otherwise particularly stated, refers to (wt/wt) % for solid/solid, (wt/vol) % for solid/liquid, and (vol/vol) % for liquid/liquid.
Preparative Example 1
Preparation of Antifreeze/Coolant of Examples 1 to 5
The present inventors used 90-95 wt % of glycol (e.g., ethylene glycol) as a main component for preparation of an antifreeze or a coolant. 1.0-6.0 wt % of cyclohexane dicarboxylic acid was used as an anti-corrosive agent for aluminum- and iron-based materials, and 0.1-0.5 wt % of azole or thiazole was used as an anticorrosive agent for copper and brass materials. The present invention is characterized in that the combination of cyclohexane dicarboxylic acid and non-reducing polyol was used to improve the effects in preventing cavitation erosion and gap corrosion. The non-reducing polyol [mannitol (Basf, Germany), sorbitol (Kanto Chemical, Japan), or xylitol (Sigma-Aldrich, Canada)] was used in a content of 0.1-0.5 wt %. Specifically, compositions of examples and comparative examples of the present invention were prepared by weighing components of which contents are shown in Table 1 below, putting ethylene glycol into the container, and then heating the solution to reach a temperature of 40-60° C. while stirring was conducted for a homogeneous solution.
TABLE 1
Compositions of examples and comparative examples
Example
Comparative example
Component (wt %)
1
2
3
4
5
1
2
3
4
5
Ethylene glycol
92.82
91.60
91.55
91.72
91.30
93.12
92.90
92.05
92.12
91.70
t-butyl benzoic
1.0
1.2
1.0
1.0
1.0
1.0
1.2
1.0
1.0
1.0
acid
Sebacic acid
2.0
2.0
1.8
2.0
2.0
2.0
2.0
1.8
2.0
2.0
Decanedicarboxylic
0.5
—
1.0
0.5
0.5
0.5
—
1.0
0.5
0.5
acid
Cyclohexanedicarboxylic
1.2
1.5
1.2
1.2
1.2
1.2
1.5
1.2
1.2
1.2
acid
Tolyltriazole
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
Benzotriazole
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
2-
—
—
—
0.1
0.1
—
—
—
0.1
0.1
mercaptobenzothiazole
Mannitol
0.3
—
—
0.2
0.2
—
—
—
—
—
Sorbitol
—
0.3
—
—
0.2
—
—
—
—
—
Xylitol
—
—
0.5
0.2
—
—
—
—
—
—
Test Example 1
Cavitation Erosion Test
For a cavitation erosion test, the compositions of examples and comparative examples were mixed with combination water defined in the ASTM D 1384 metal corrosion test (solution in which sulfuric anhydride 148 mg, sodium chloride 165 mg, and sodium hydrogen carbonate 138 mg are dissolved in 1 l of distilled water) to reach concentrations of 50 vol %, respectively. Two sets of metal test specimens were installed. The discharge pressure of the water pump was 1.6 kgf/cm 2 . The rotational speed of the water pump impeller was 88000±100 RPM. The temperature of liquid was 110±5° C. The operating time was 672 hours. As another method, the concentrations of compositions were 30 volt, respectively, and two sets of metal specimens were installed. The discharge pressure of the water pump was 1.0 kgf/cm 2 . The rotational speed of the water pump impeller was 5500±100 RPM. The temperature of liquid was 95±5° C. The operating time was 1,008 hours. Upon the completion of each test, the test specimens were washed with acid. The weight changes of the test specimens were determined in the error range of 0.1 mg. The water pump was disassembled, and the degree of cavitation erosion was measured by utilizing a table of grading specified according to the ASTM D 2809. The results were tabulated in Table 2 below, and the appearances of the water pumps after the test for Examples 1 to 5 and Comparative Example 2 were shown in FIG. 1 .
TABLE 2
Water pump test results
Example
Comparative example
Test item
Standard
1
2
3
4
5
1
2
3
4
5
Weight
Aluminum
±0.15
−0.06
−0.05
−0.06
−0.07
−0.04
−0.15
−0.14
−0.14
−0.16
−0.16
change
Cast ion
±0.15
+0.02
−0.02
+0.03
−0.02
+0.03
−0.09
+0.07
+0.12
+0.15
−0.15
of test
Steel
±0.15
−0.01
+0.02
−0.02
−0.02
−0.02
−0.07
−0.10
+0.08
−0.07
+0.07
specimen
Brass
±0.15
−0.02
−0.02
+0.03
−0.02
−0.06
−0.11
−0.12
+0.14
−0.15
−0.13
(mg/cm 2 )
Solder
±0.15
−0.10
−0.08
−0.08
−0.09
−0.10
−0.14
−0.18
−0.17
−0.15
−0.17
50%,
Copper
±0.15
−0.04
−0.03
−0.04
−0.03
−0.02
+0.05
−0.04
+0.05
−0.06
+0.04
98° C.,
672
hours
Appearance of test
Not corroded
Not
Solder
Not
Not
Solder
specimen
corroded
corroded
corroded
corroded
corroded
Appearance grade of
9
9
10
9
10
7
5
7
5
6
impeller of water pump
Weight
Aluminum
±0.15
−0.08
−0.09
−0.09
−0.07
−0.04
−0.14
−0.14
−0.13
−0.18
−0.15
change
Cast ion
±0.15
+0.05
−0.03
+0.05
−0.02
+0.03
−0.10
−0.11
−0.11
+0.10
−0.12
of test
Steel
±0.15
−0.03
−0.04
+0.04
−0.02
−0.02
−0.09
−0.08
+0.09
−0.10
+0.09
specimen
Brass
±0.15
−0.06
−0.07
−0.05
+0.06
−0.06
−0.13
−0.12
−0.13
−0.12
−0.14
(mg/cm 2 )
Solder
±0.15
−0.12
−0.11
−0.13
−0.09
−0.10
−0.14
−0.13
−0.15
−0.13
−0.16
30%,
Copper
±0.15
−0.07
−0.05
−0.07
+0.03
−0.04
−0.12
+0.11
+0.13
−0.14
+0.11
95° C.,
1,008
hours
Appearance of test
Not corroded
Solder,
Solder
Solder
Solder
Solder
specimen
aluminum,
and cast
corroded
and cast
and
and cast
iron
iron
aluminum
iron
corroded
corroded
corroded
corroded
Appearance grade of
9
9
10
9
10
7
5
7
5
6
impeller of water pump
As can be seen from Table 2 above, in the cavitation erosion test results under conditions of 50%, 110° C., and 672 hours, the compositions of the examples showed no corrosion on aluminum, cast iron, steel, brass, solder, and copper, while the compositions of Comparative Examples 2 and 5 showed corrosion on only solder. However, in the cavitation erosion test results under conditions of 30%, 95° C., and 1,008 hours, the compositions of the examples exhibited satisfactory anti-corrosive performance, while the compositions of the comparative examples showed corrosion on solder, aluminum, and cast iron, resulting in poor performance of preventing cavitation erosion for a long time at a concentration of 30%. As can be seen from Table 1 and FIG. 1 , the compositions of the present examples exhibited more excellent performance of preventing erosion of the water pump impeller due to cavitation and relatively lower changes in metal weight than the compositions of the comparative examples. Therefore, it can be seen that the compositions of the present invention also exhibited great effects in the performance of preventing metal corrosion.
Test Example 2
Gap Corrosion Test
For a gap corrosion test, the compositions of examples and comparative examples were mixed with combination water defined in the ASTM D 1384 metal corrosion test (solution in which sulfuric anhydride 148 mg, sodium chloride 165 mg, and sodium hydrogen carbonate 138 mg are dissolved in 1 l of distilled water) to reach concentrations of 33 vol %, respectively. In a 1 l glass tall beaker, a fluoroelastomer sheet was positioned between an aluminum casting with grooves and an aluminum casting without grooves, which were then immersed in the solution such that the solution uniformly infiltrated into the grooves. The operation was conducted at 100° C. for 672 hours. The gap corrosion of the aluminum castings was observed by a digital microscope. The results were tabulated in Table 3 below, and appearances of impellers for the examples and Comparative Examples 1 and 2.
TABLE 3
Results on gap corrosion test
Test
Example
Comparative example
item
Standard
1
2
3
4
5
1
2
3
4
5
Appearance of
Not
Partially
Partially
Corroded
Corroded
Corroded
groove of aluminum
corroded
corroded
corroded
casting
As can be seen from Table 3 and FIG. 2 , the compositions of the examples showed no gap corrosion on the aluminum castings and exhibited excellent anti-corrosive effects, but the compositions of the comparative examples showed gap corrosion on the aluminum castings. Therefore, it can be seen that the combination of cyclohexane dicarboxylic acid and non-reducing polyol exhibited performance of preventing gap corrosion.
The composition of the present invention exhibited excellent anti-corrosive effects against cavitation erosion and gap corrosion due to a synergy effect by the combination of cyclohexane dicarboxylic acid and non-reducing polyol. It can be seen that the long-term durability of the antifreeze was enhanced from the enhancement in anti-corrosive performance for internal metal materials in the cooling system, the improvement in durability against cavitation erosion of aluminum, and the enhancement in the anti-corrosive performance on the rotating water pump.
Although the present invention has been described in detail with reference to the specific features, it will be apparent to those skilled in the art that this description is only for a preferred embodiment and does not limit the scope of the present invention. Thus, the substantial scope of the present invention will be defined by the appended claims and equivalents thereof. | The present invention relates to a composition for an antifreeze liquid or a coolant. The present invention provides the composition for the antifreeze liquid or the coolant comprising: (a) a glycol-based antifreeze agent; (b) a cyclo hexane dicarboxylic acid; and (c) a non-reduced polyol. Generally, a mixture of mono- or dicarboxylic acid, which is used as a corrosion inhibitor agent, and an inorganic additive is prone to cavitation erosion and corrosion of gaps, but when a composition is comprised by using in parallel the cyclo hexane dicarboxylic acid and the non-reduced polyol, a synergy effect is created, thereby exhibiting a superior corrosion prevention effect with respect to cavitation erosion and corrosion of gaps inside a cooling apparatus. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an opening roller for a spinning mill machine for the opening and cleaning of cotton fibers. It is concerned particularly with an opening roller provided with a predetermined number of beater elements distributed on and fixed to the periphery of the opening roller for grasping and opening flocks of cotton fibers.
2. Description of Related Art
Opening rollers for so-called coarse cleaning machines are well known. For example, Maschinenfabrik Rieter AG markets such a machine under the brand name Mono Roller Cleaner B4/1. The same company has applied for letters patent in Switzerland for a further machine of this type under the number CH-00321/89-0.
These machines have beater elements distributed on the periphery of the opening roller. Such beater elements are round rods fastened radially to the periphery. They are distributed in a predetermined manner over the peripheral surface.
In these machines the fibrous material is fed toward the periphery of the roller at one axial end thereof and collected there by the beater elements. The beater elements pull the material (usually in the form of flocks over cleaning grid bars. Gradually the material is brought to the other axial end of the opening roller by means of guide chambers, where the opened fibers are conveyed through the outlet of the machine by means of centrifugal force.
The cleaning machine disclosed in Switzerland Patent Application No. CH-00321/89-0 is represented semischematically in FIGS. 1 and 2, to facilitate explanation later on of the principles of the present invention on the basis of this representation.
3. SUMMARY OF THE INVENTION
It is desirable that the opening effect of such machines be more efficient, that is to say, that the flocks be fed more efficiently with the power input remaining the same or smaller, and/or with the fiber flocks fed in being opened more efficiently and if possible, more gently. Hence, the term "more efficiently," means an increase in the opening of large fibers flocks into a plurality of smaller flocks. As far as possible according to the principle of cotton cleaning, the cleaning means primarily opens the flocks, in order to be able to remove the dirt adhering to and between the fibers more effectively.
According to the present invention, the beater elements no longer have simple surfaces directed radially to the axis of rotation of the opening roller. Rather, the beater elements according to the invention have fiber-contacting rod portions that are inclined forwardly in the direction of rotation of the opening roller surface on which they are received.
An advantage of the beater elements according to the invention lies in that the fiber flocks are thrown about less by impacts with the beater elements. Rather, they are grasped by means of the beater elements in a small part of the fiber bunch and the fiber bunch is subsequently pulled through the surrounding air as a tuft which is opened into smaller parts through the retarding tendency of the surrounding air.
For good cleaning in a machine of this type, it is desirable that the fiber bunch remain as long as possible on the beater elements and be pulled by the beater elements over the cleaning grid. That is to say, the relative speed between the fiber bunch and the beater elements should be as small as possible while the fiber bunch is being pulled over the cleaning grid.
The desired action might be likened to a kind of pinching of the fiber bunches in a way that only a small part of each fiber bunch is actually engaged by the pinching components, leaving the biggest part of the fiber bunch free to be beaten intensively by means of the grids without producing a rolling effect between the beater element and the grid bars. Rolling of the fiber bunches is disadvantageous, because rolling effects are accompanied by a danger of producing entanglement of fibers which may lead later on at least to a certain amount of neps.
The present invention provides a beater rod arrangement that functions in a manner comparable in some respects to a fiber pinching system. The fiber bunch contacting portions of the beater rods are not too thick and are arranged in a way that the bunch is kept by the rod portions over the grid bars for as long a distance as possible.
Also, the fiber bunch should come back to the beater elements after the cleaning grid, in order to be transported properly through the cleaning machine. The fiber flocks move a stage further in the axial direction of the opening roller in a transfer chamber to be described later. Subsequently they are grasped again by further beater elements, and so on stage by stage, until the fiber bunch, reduced in size and cleaned, leaves the machine on the other axial end of the opening roller.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are depicted in the accompanying drawings, in which
FIG. 1 is a cross section through a cleaning machine according to the Swiss Patent Application No. CH-00321/89-0 with an opening roller according to the present state of technology represented semi-schematically;
FIG. 2 is another view of the cleaning machine of FIG. 1, with the opening roller being represented semi-schematically in a longitudinal section;
FIG. 3 is a partial section through a peripheral portion of the opening roller in a radial plane containing the longitudinal axis of the roller, with a beater element according to the invention being represented as fixed to the surface of the opening roller;
FIG. 4 is a top view in the direction IV (FIG. 3) of the beater element of FIG. 3;
FIG. 5 is a lateral view in the direction V (FIG. 4) of the beater element of FIG. 3;
FIG. 6 is similar to FIG. 3 but showing another form of beater element in accordance with the present invention;
FIG. 7 is a top view similar to FIG. 4 but showing the beater element of FIG. 6;
FIG. 8 is a lateral view similar to FIG. 5 but showing the beater element of FIG. 6;
FIG. 9 is a view similar to FIG. 3 but showing another form of beater element in accordance with the present invention;
FIG. 10 is a top view similar to FIG. 4 but showing the beater element of FIG. 9; and
FIG. 11 is a lateral view similar to FIG. 6 but showing the beater element of FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a cleaning machine 1 provided with a rotatable opening roller 2 which can be driven. Beater elements 3 (also called "beating " elements) are distributed over the roller periphery in a predetermined manner as seen in the axial direction as well as in the radial direction. These beater elements 3 are fastened to the opening roller and extend radially with respect to the axis of rotation of the opening roller.
The cleaning machine also has a cleaning grid 4 assembled from single grid bars 5. This grid 4 is positioned opposite a part of the periphery of the opening roller, with a predetermined spacing between the tips of the beater elements 3 and the bars of the grid.
Opposite to the cleaning grid 4, the cleaning machine has chamber walls 6 above the opening roller, as seen in FIG. 1. These walls are arranged inclined to the axial direction of the opening roller, as in FIG. 2, in order to define guide chambers (not shown) through which the fibers may pass. In these guide chambers, the fiber flocks fed in are transported spirally in an axial direction as the opening roller rotates in the direction D, until the opened flocks again leave the cleaning machine through an outlet 8.
This general arrangement is present in the Mono Roller Cleaner B4/1 referred to above, which also employs beater elements like the beater elements 3 shown in FIGS. 1 and 2.
FIGS. 3-5 show a beater element 3.1 according to the invention. This beater element 3.1 includes a rod 10 and a rod 11, which together form a double hook shaped element with a fixing loop 12. The fixing loop 12 serves for fixing the beater element 3.1 on the opening roller 2 by means of a screw 13.
As can be seen from FIG. 3, each of the rods 10 and 11 has a free end portion disposed at an angle alpha opposite to the surface of the opening roller. That is, each rod 10 and 11 protrudes outwardly from the peripheral surface at an inclination substantially less than the radial protrusion characteristic of the beater elements used prior to the present invention. With the help of this oblique position, the surfaces of the beater elements are inclined relative to the surface of the opening roller as explained above, to improve their action on the fibers.
Furthermore, FIG. 3 shows that the rods 10 and 11 have a predetermined diameter G. This diameter can vary between four and eight millimeters. However, a diameter of five millimeters is preferred. A replaceable, round wire, preferably of spring steel, may be used for the production of the beater element 3.1.
It can be seen from FIG. 5 that a free end portion of each of the rods 10 and 11 has a predetermined angle beta to a tangential plane E, parallel to the axis of rotation of the opening roller. The point of tangency between the roller surface and the plane E is located at the fixing axis B of the screw 13.
The angle beta is about 90 in the example shown, so that a free end portion of each of the rods 10 and 11 opposite to a prolongation A.1 of the radius A of the cross section of the opening roller is inclined forwardly at an angle gamma in the direction of rotation D. This angle gamma is the angle between the rear face of the outer end portion of a rod and a radius A of the roller so located as to touch the trailing surface of the rod. An angle γ of four degrees (4°) has been found to give good results. However, the selection of the angle beta, and consequently of the angle gamma, can be different, according to the size of the flocks to be cleaned and the flock material and can best be determined empirically. The same applies to the angle alpha in FIG. 3.
However, as the beater elements can be manufactured from flexible steel wire, it is a simple matter to form to the angles so as to suit the requirements in a particular instance.
In FIGS. 3 and 4, it is additionally represented with dash dotted lines, that a beater element 3.2 can have only one rod 14, instead of two. The rod 14 is shown fixed on the opening roller 2 in FIG. 4 and has angles beta and gamma, as represented with FIG. 5.
A further variant is provided when a beater element 3.1 is combined with beater element 3.2. The beater element 3.2 is arranged over the beater element 3.1 and fixed together with an appropriate extended screw 13, so that a threefold rod combination exists as shown in FIGS. 3 and 4. The end surfaces (not shown) of the rods 10, 11 and 14 must be at the same distance from the surface of the opening roller 3 and must have the same spacing from the grid bars 5.
FIGS. 6 to 8 show variants of the beater elements of FIGS. 3 to 5. In FIG. 6, each beater element 3.3 has rods 16 and 17 selected with the same diameter D as the rods 10 and 11 of the beater element 3.1. However, the rods 16 and 17 have outer end portions provided with a type of wave shaped bends, designated with R. The remaining parts correspond to parts of the beater elements 3.1 and they are designated with the same reference symbols.
These bends have the purpose that the fibers, which are grasped by the respective rods 16 and 17 and are gliding thereby along the bends against the free ends of the rods 16 and 17, are braked correspondingly to the bends R.
It is also represented in this variant, that a single rod 18, for example from the beater element 3.4, can be provided. This single rod also has bends R, with the same effect as with the rods 16 and 17. The beater elements 3.3 and 3.4 can be combined in the manner described above in connection with FIGS. 3 to 5.
FIGS. 9 to 11 depict still another form of beater element 3.5 that includes rods 19 and 20, each provided with notches which are open in the direction along the surface of the opening roller 2. The remaining parts correspond to the beater element 3.1 and are designated with the same reference symbols. A beater element 3.6 is represented as a variant of the beater element 3.2 of FIG. 5. The notches 22, as represented with FIG. 11, open in the direction of rotation D of the opening roller.
The object of these notches, as with the object of the sinusoidal shaped bends of FIG. 6, is to increase the friction between the fibers and the rods 19 and 20, for those fibers which, as described earlier for the rods 9 and 10, work their way against the free ends of the rods 19 and 20.
It is not in all instances essential that the beater elements of the present invention be formed of steel wire. Nor is it always essential that they be of a round cross section. Other materials and other profiles can be used. A profile which is more favorable aerodynamically than the round profile which is similar to the profile on the carrier flap.
Furthermore, the use of the opening roller is not limited to the cleaning machine described. The beater elements of the invention can also be used on rollers which are used in bale opening devices. The present state of technology for opening rollers in bale opening machines consists as a rule of toothed rollers, which are arranged with each other in a row to form a toothed roller body, which opens the fiber flocks from the surface of fiber bales and passes them to a pneumatic transport device.
The possibility is completely feasible in that, instead of the toothed rollers, a roller body as described is used, which is fitted to the opening roller of a bale opening device with the beater elements described. | A fiber opening and cleaning machine includes an opening roll provided with inclined beater elements. Such beater elements have a wave shaped design and are considerably less in diameter than the relatively larger diameter beater rods customarily used in such machines. The advantage of the wave shaped beater elements lies in the grasping and spiral conveying of the fiber flocks fed into the machine. | 3 |
BACKGROUND OF THE INVENTION
The invention relates to a luminaire, in particular a wall or ceiling luminaire protected against sprayed or splashed water, for receiving at least one elongated gas-discharge lamp, having an enclosure able to be assembled into a closed form from a transparent lower part which can be mounted in a fixed position and which holds electrical gear and a transparent upper part. Luminaires having gas-discharge lamps are generally particularly economical light-sources which can be operated with long lives and with a high light yield in relation to the electrical power which has to be applied. Widespread use is made of such lamps particularly in industrial areas and in domestic side rooms, where certain deficiencies in the spectral distribution of the light and particularly in the length and shape of the lamps impose restrictions in respect of the decorative design of luminaires but are not such an important consideration as in, say, the living area. Luminaires in industrial areas and in basements or garages are also very often subject to requirements for being of a construction which is at least protected against water and are, at the same time, usually highly developed mass-produced products whose price is keenly costed.
Known luminaires of this kind have a lamp enclosure which comprises a highly-transparent upper part and a non-transparent lower part. With a division of this kind, the non-transparent lower part may then be formed by a shell of synthetic resin which absorbs the heat which is given off by the lamps, particularly in the region of the electrodes at the ends, and above all the heat from a ballast (choke) which is arranged inside the lamp, whereas the upper part is produced from a highly transparent thermoplastic plastics material which makes possible the desired division of the radiated light but which has a very much lower resistance to temperature and a very much greater thermal expansion than the thermoset material of the lower part.
The terms “upper part” and “lower part” which are used here and which are commonly employed in German practice do not refer to the respective installed positions, and instead lower part denotes the body of the enclosure, which is to be fastened to a wall or ceiling and which generally also serves as a mounting for the electrical gear, whereas “upper part” denotes a cover which is detachably held by the lower part. It is thus possible, in the case of ceiling mounting say, for the upper part to be at the very bottom.
However, the lower part of non-translucent thermoset material, which is conventionally more resistant to thermal and mechanical stresses, absorbs a considerable proportion of the light which is emitted from the lamp or lamps inside the enclosure. What is more, the distribution of the light is unsatisfactory if large areas of shadow occur on the side on which the lower part is situated. Where mounting is on a wall or ceiling, dark shadowed zones giving an unwanted pattern of illumination then arise, particularly in the areas adjoining the luminaire.
What is more, attempts have already been made to produce trough-like luminaires of this kind which have a transparent lower part made of a material which is the same as or similar to the material of the upper part. However, it has been found that variations in the properties of the material result in mounting and sealing problems which cannot be solved, or at all events not at a cost that meets the demands of the market.
It is therefore an object of the invention to provide a luminaire of the kind considered here which makes possible improved light emission and light distribution without at the same time abandoning the standards of reliability and ruggedness, of easy mounting and handling and in particular of low-cost manufacture to which these lamps have been further developed.
SUMMARY OF THE INVENTION
In accordance with the invention, this object is achieved by a basic luminaire of the aforementioned kind wherein improved light distribution and light emission are to be achieved simply by virtue of the fact that the lower part too is made from a translucent or highly transparent material and the lower part and the upper part are produced from the same batches of thermoplastic plastics material. The distributed light is thus not screened off by the lower part but is also, to a large degree, transmitted. In this way, areas of dark bordering a luminaire of this kind are avoided when mounting is on a wall or ceiling and, at any rate with light walls or ceilings, use can also be made of the light fluxes incident on them which are reflected into the room.
However, the particular sensitivity of the transparent thermoplastic material to heat calls for special precautions to be taken against deformation. Above all, it has to be ensured, without employing designs which, for production reasons, are expensive, complicated and difficult to handle, that the sealing of the enclosure which gives protection against water is not lost as a result of the material heating up and of its expansion which is high due to temperature.
In this regard, it has been found to be effective for the lower part to be produced from thermoplastic plastics material from the same batch as the upper part. However, this requirement cannot then be met simply by virtue of the fact that the material has the same name in both cases. Materials from the same manufacturer which are nominally the same, or even different batches from the same manufacturer, may produce an unsatisfactory match. It may even be useful not simply to rely on the same batch and its homogeneity in the case of the starting material but, in addition, for operation to be such that there is a match in respect of the starting material and the operating conditions. In this way, provision is usefully made for the upper and lower parts to be moulded in a common injecting moulding operation on the same injection moulding machine, or even for a single injection mould to be designed which combines one cavity for the lower part and one cavity for the upper part and which has injection passages which are largely symmetrical or largely of matching lengths.
With material which is the same and finely matched in this way, the changes which result, even with high thermal expansion, are uniform and do not cause any displacement, and stop the upper and lower parts from splaying apart and becoming unsealed as a result.
BRIEF DESCRIPTION OF THE DRAWINGS
Further embodiments of the invention can be seen from the claims. In the following description of an embodiment these, and their advantages, are explained. In the drawings:
FIG. 1 is a cross-section through a luminaire,
FIG. 1 a is a cross-section of a variant of the luminaire of FIG. 1 ,
FIG. 2 is a partial longitudinal section on line II-II in FIG. 1 ;
FIG. 3 is a cross-section through a modified form of luminaire.
DESCRIPTION OF PREFERRED EMBODIMENTS
A luminaire which is denoted as a whole by reference numeral 1 has an enclosure which is denoted as a whole by reference numeral 4 , which is assembled from a upper part 2 and a lower part 3 , which extends, in the direction of viewing of FIG. 1 , in an approximately prismatic elongated shape adapted to a gas-discharge lamp 5 of elongated tubular shape situated inside it, and which terminates at the ends in the form of caps. The upper part 2 is composed in a known manner of a transparent thermoplastic plastics material such as, say, an acrylic “glass” (PMMA) or a transparent polycarbonate. The lower part is composed in a novel manner of the same material, with the match being obtained not only in respect of the basic material and its additives and, if required, the source of supply, but also in respect of the batch from which supply takes place, the state of storage and of temperature and the processing operation, and in particular the extrusion operation.
This match is usefully achieved by having the thermoplastic material injected, in a common injection operation, into one injection mould or cavity for the upper part 2 and one injection mould or cavity for the lower part 3 . The matching is assisted to a further degree by having a single injection mould contain both a cavity for an upper part 2 and a cavity for a lower part 3 , in which case the distances of injection and the injection passages are also matched to one another. The basic concept of almost twinned injection moulding of this kind of complementary parts of the enclosing shell is of course also open to multiplication, where a plurality of upper and lower parts are injection moulded simultaneously in one mould, though there are practical limits which militate against such multiplication in the form of the size of the injection moulds and the clamping forces which then have to be applied. With current technology, the enclosure parts, which are elongated and are thus rather large simply for this reason, will not go beyond a single pair of upper and lower parts.
This at any rate gives an injection moulding operation in which the injection moulding machine, via its injection gate, introduces a unitary injectable material into a mould, in which mould the material distributes itself, within the mould, to the cavities, which are situated next to one another, in a way which is very largely symmetrical and at a balanced temperature.
The particular purpose of this way of arranging the mould and the process is to achieve, for the behaviour of the enclosure with temperature, and in particular for its expansion with temperature, the best possible match between the upper and lower parts. The enclosure 4 is subject to thermal stresses from the exterior caused by varying temperatures of the ambient air, and possibly also by incident solar radiation or by precipitation, but above all it undergoes thermal stresses which are caused by the heat generated by the gas-discharge lamp 5 , predominantly in the region of the electrodes at the ends, and also by a ballast 6 , which is likewise intended to be covered and protected by the enclosure 4 and whose effect would only be that of a loss-free choke (induction coil) in the ideal case and which instead, for reasons of size and cost of manufacture, does cause electrical losses, which may result in a temperature of up to more than 200 C.
Whereas conventional enclosures for gas-discharge lamps have been fitted with a lower part made of a thermally rugged thermoset plastics material which absorbs the thermal stresses with a high temperature resistance and low thermal expansion, the transparent thermoplastic material which is used in accordance with the invention is very much more prone to such stresses. Thus, in the present case the solution to the problem lies not in a more rugged lower part but in matching the upper and lower parts so that, when thermal expansions cannot be kept low due to the material, the thermal expansions can be matched to one another and in this way the possibility of stressing and distortion of the enclosure can be ruled out.
The enclosure is thus made transparent in the lower part 3 too, which means that light which is emitted by the gas-discharge lamp 5 in the region of the said lower part 3 emerges, the casting of shadows is avoided around the lower part 3 and, where mounting is on a wall or ceiling, it brings additional light into the room by reflection, with the enclosure as a whole also acquiring an advantageously bright appearance.
It will be appreciated that in place of the individual gas-discharge lamp 5 , two or more gas-discharge lamps would equally well be arranged in an enclosure in a perfectly normal way without this resulting in anything different happening.
With regard to the stresses, and in particular the thermal stresses, on the enclosure which were considered above, a key role is played by the region of the connection between the upper part 2 and the lower part 3 , in which case provision has to be made both for the inexpensive and uncomplicated manufacture which is a prerequisite for mass-produced products of this kind where the competitive pricing is keen, and for uncomplicated handling by the installing engineer or purchaser. Accordingly, there is provided for the purpose of connecting the upper and lower parts a latching arrangement 7 in which a sealing groove 8 is moulded-in on one side, namely in the present case on the side on which the lower part 3 is situated. The sealing groove is open in a direction transverse to a closing movement of the upper part 2 towards the lower part 3 and is overlapped by an insertable rim 9 on the upper part, which rim 9 has, in turn, an outwardly projecting annular bead 10 which fits into the annular groove. This latching arrangement, which is in itself typical, is supplemented, for the purposes of improved protection against water, by having the insertable rim 9 (on the upper part 2 ) engage in a receptacle 11 for the insertable rim 9 , which receptacle 11 is U-shaped in cross-section, extends round in a loop at the edge, and fits round and covers the insertable rim 9 . Mechanical stresses on the enclosure 4 , in a water test say, and particularly when occurring in conjunction with thermal stresses on the enclosure, thus do not result in the upper part 2 and lower part 3 splaying apart, which would be a risk as far as protection against splashed or sprayed water was concerned.
The annular bead 10 , which is formed simply by the injection moulding of the upper part 2 , provides the simplest and cheapest form of latching engagement. It will however be appreciated that the insertable rim 9 may likewise be provided, in cross-section, with a sealing groove 9 a which corresponds to and is situated opposite the sealing groove 8 , thus leaving an intervening space of circular cross-section into which an elastic ring-seal 9 b extending round in a loop has to be inserted (see FIG. 1 a ). This is what will need to be provided particularly in the case of materials which prove to be too solid or too rigid for a latching connection.
In FIG. 1 , there can be seen on both sides in the region of the connection between the upper part 2 and lower part 3 , gripping lugs 12 , 13 which are integrally moulded on the upper part 2 and lower part 3 respectively. Looking in the direction of viewing, and hence in the longitudinal direction of the enclosure 4 , these are offset from one another just sufficiently far for them not to overlap one another. They make it possible for the parts of the enclosure to be released from the latched position with the fingers (i.e. without tools).
As can also be seen in FIG. 1 , the ballast 6 is screened off from the lower part 3 by a screening member 14 . This a metal plate bent into a U which is fixed at the bottom between the ballast 6 and pedestal extensions which are formed on the bottom region of the lower part 3 but which extends up at the sides, at a distance from the ballast 6 , approximately to the same height as the latter, to enable radiant heat and also convection in the direction of the lower part 3 to be intercepted as satisfactorily as possible.
Shown in the longitudinal section in FIG. 2 , as a detail, is only a small part of the overall length of the luminaire, what can be seen in particular being the ballast 6 , which has a bottom portion 15 which projects particularly for mounting purposes, and the screening member 14 , which likewise projects beyond the ballast 6 in the longitudinal direction. As prefitted for transport, by a screw 16 , say, both of these items are fastened to a pedestal region 17 of the lower part 3 .
This pedestal region 17 has a vertical through-opening 18 which opens in the upward direction from an extension 19 which, with insulation, fits through a mounting hole 20 in the ballast 6 , or rather in the bottom portion 15 , and a mounting hole 21 in the screening member 14 . An insulating washer 22 and a preferably metallic washer 23 are provided to allow the luminaire 1 , when it is mounted on a wall or ceiling, to be screwed firmly to a support by a screw or a comparable fixing means F (schematically indicated in FIG. 2 by a center axis through the bore 18 ) which passes through them in the outward direction. In this way the ballast, being a critical component in view of its particular weight and the heat it generates, is fixed in place relative to a structural support in an expeditious manner. The insulating washer 22 , which is of a cup-like form, enables the fixing means F to be pressed against the bottom portion 15 of the ballast regardless of an amount by which the extension 19 may project.
Basically, a seal which generally has to be provided for the mounting opening can be made internally in the region of the through-opening 18 or the insulating washer 22 . In the present case a receptacle 24 , in which a sealing washer 26 has to be inserted, is provided at the bottom side, and thus on the outside, in the region of a foot 25 on the lower part 3 .
A modified embodiment of the luminaire, which is shown in FIG. 3 , is denoted as a whole by reference numeral 31 and once again has an enclosure 34 comprising an upper part 32 and a lower part 33 , a marked difference from the luminaire 1 considered above being the fact that what is provided for a latching arrangement 37 is an insertable rim 39 which is in the form of a U-profile in cross-section. Like the insertable rim 9 in the case of the luminaire 1 , this insertable rim 39 is intended, when there is a closing movement between the upper part 32 and the lower part 33 , to penetrate into a U-shaped receptacle 41 in that edge of the lower part 33 which faces towards the upper part 32 , and to latch there in a lateral sealing groove 38 by an annular bead 40 which fits the latter. The forming of the insertable rim 39 as an open hollow profile gives some elasticity in the transverse direction and hence a springiness which presses the annular bead 40 into the annular groove 38 without the pressing forces involved preventing the upper part 32 and lower part 33 from being inserted in one another or separated from one another. To obtain preset pressing forces, a pre-loading may be provided by design by making the insertable rim 39 wider in the region of the annular bead 40 than the receptacle is in the region of the sealing groove 38 . When the upper part 32 and lower part 33 are plugged together, the insertable rim 39 is thus compressed elastically by a preset amount and/or the receptacle 41 is spread open elastically in cross-section. This improves the sealing seating in the latching region.
What is also of benefit however is a channel-like free intervening space 42 between the insertable rim 39 and the receptacle 41 . The receptacle 41 is thus not so configured in cross-section that it fits tightly around the insertable rim 39 but that it leaves a free space. This intervening space ( 42 ) has proved satisfactory in sprayed water tests as an enclosed space for keeping out of the interior of the enclosure small amounts of water which, possibly while the pressure of the water jet from outside is high, manage to pass through the seal between the annular bead 40 and the sealing groove 38 . In this case, sufficiently well sealed planar contact between the overlapping continuations of the upper part 32 of the enclosure and the lower part 33 of the enclosure stops water from running into the interior of the lamp enclosure 34 from the intervening space 42 . On the other hand, the insertable connection between the upper part 32 and lower part 33 cannot be considered hermetically sealed, which means that moisture which might have a minor effect can make its way into the open air as a result of diffusion movements and compensating movements at the time of variations in heat and pressure.
For the stiffness and also for the sealing of the latching engagement 37 , it is advantageous for there to be dose contact between the insertable rim 39 and the receptacle 41 created by a configuration of curved cross-section for an outer intervening gap 43 . This gap prevents sprayed water, even in a tight jet, from penetrating through to the region of the seal between the sealing groove 38 and the annular bead 40 and it masks off this region with an end-flange 44 which at the same time makes a contribution to the shape-induced stiffness, in the longitudinal direction, of the profile forming the insertable rim. | A luminaire, in particular a wall or ceiling luminaire protected against sprayed or splashed water, for receiving at least one elongated gas-discharge lamp, having an enclosure able to be assembled into a closed form from a transparent lower part which can be mounted in a fixed position and which holds electrical gear and a transparent upper part, is so designed, with the aim of achieving a form for the upper part and lower part which is economical and meets the demands of the market and in which the two are matched to one another in relation to thermal stresses, that the lower part and the upper part are produced from the same batches of thermoplastic plastics material. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to vehicle safety systems employing air bags and more particularly to an air bag chute for an air bag.
BACKGROUND OF THE INVENTION
[0002] In known air bag deployment arrangements, deployable outer doors of an air bag housing are separated by at least one tearable seam, against which a deploying air bag exerts a force when the bag is inflating. The expanding bag exerts force only on a portion of the seam centrally located with respect to the bag's leading surface.
[0003] There is a need for an air bag deployment arrangement which will allow the air bag to exert pressure substantially evenly along the entire extent of the tearable seam, thereby reducing maximum force from being exerted only against a portion of the air bag door located centrally in front of the deploying air bag.
SUMMARY OF THE INVENTION
[0004] An air bag chute has a compartment having a front cover panel including at least one frangible seam therein, a rear aperture opposite the front cover panel adapted to receive a deploying air bag, and first and second walls extending between the rear aperture and the front cover panel, at least one of the walls extending laterally outwardly from the rear aperture towards the front cover panel, whereby the compartment is adapted to enable a deploying air bag to expand at least partially parallel to the frangible seam before contacting the front cover panel.
[0005] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0007] FIG. 1 is a perspective view of a vehicle with an instrument panel including an air bag safety system employing an air bag chute with an air bag according to the principles of the present invention;
[0008] FIG. 2 is cross sectional view of the air bag safety system of FIG. 1 taken along line 2 - 2 of FIG. 1 ;
[0009] FIG. 2A is a detailed cross sectional view of the air bag safety system of FIG. 1 ;
[0010] FIG. 3 is a rear view of the air bag safety system of FIG. 1 ;
[0011] FIG. 4A is an environmental view of the air bag safety system of FIG. 1 during the expansion of the air bag; and
[0012] FIG. 4B is top view of an occupant contacting the air bag after the air bag has fully expanded from the air bag safety system of FIG. 1 .
DETAILED DESCRIPTION
[0013] The following description is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
[0014] The present invention is generally related to an air bag chute for use with a safety system disposed in a motor vehicle. Although the following exemplary description refers to the use of an air bag chute disposed in an instrument panel of a motor vehicle, it will be understood that the present invention may be applicable to other types of air bag safety systems, and to different locations within the vehicle. Further, the foregoing description is understood to not limit the appended claims.
[0015] With reference to FIG. 1 , a motor vehicle 8 including a passenger area 10 is shown. The passenger area 10 includes an instrument panel 12 which is adapted to receive an air bag system 14 . In particular, with continuing reference to FIG. 1 , and additional reference to FIGS. 2, 2A and 3 , the instrument panel 12 includes an aperture 16 for receipt of the air bag system 14 . The air bag system 14 includes an air bag chute cover panel 18 coupled to an air bag chute 20 .
[0016] Panel 18 includes an outer surface 22 facing passenger area 10 , an interior surface 24 and at least one frangible or tearable seam 26 . Panel 18 may be formed of any appropriate polymeric material, such as thermoplastic polyolefin (TPO), and may be formed in any shape as desired to coordinate with the instrument panel 12 and the passenger area 10 . Cover panel 18 may alternatively include a molded in air vent 28 (shown in phantom) operable to be coupled with the heating and cooling system (not shown) of the motor vehicle 8 , to provide the passenger area 10 with pre-heated or cooled air.
[0017] Interior surface 24 of panel 18 may include at least one molded feature 30 , such as molded protrusions, operable to couple the air bag chute 20 to panel 18 . Additionally, it will be understood that any appropriate coupling mechanism could be used to fasten interior surface 24 to the air bag chute 20 such as, for example, adhesives, mechanical fasteners, or in the alternative, the instrument panel interface 18 could be integrally formed with air bag chute 20 .
[0018] In addition, interior surface 24 may define a plurality of flanges 32 operable to couple panel 18 to a surface of vehicle 8 . Further, the second surface 24 may include projections 34 to couple the second surface 24 to the instrument panel 12 . It should be noted, however, that any appropriate mechanism could be employed to couple the second surface 24 to the instrument panel 12 and motor vehicle 8 .
[0019] The at least one seam 26 may be generally formed along the centerline C of panel 18 , however, the seam 26 may be formed at any desirable location on panel 18 , or in the alternative, the seam 26 may include additional horizontal and vertical elements (not shown). The seam 26 further serves to divide panel 18 into two doors 29 , however, depending on the seam 26 , the doors 29 may be in various shapes and quantities. The seam 26 is generally integrally formed with panel 18 , and typically seam 26 is formed by molding a pre-selected area of panel 18 with a reduced thickness T 1 as compared to a thickness T 2 of panel 18 (as best shown in FIG. 2A ). Thus, the reduced thickness T 1 enables the seam 26 to fracture to enable an air bag B (as shown in FIG. 4A ) to enter the passenger area 10 via chute 20 as will be described in greater detail below.
[0020] The air bag chute 20 includes at least one door 36 coupled to a compartment 38 , in turn coupled to an air bag module 40 . A flange 42 ( FIG. 3 ) couples air bag chute 20 to interior surface 24 of panel 18 . The at least one door 36 (two doors 36 shown) may be integrally formed with the compartment 38 or may, in the alternative, be integrally formed with panel 18 .
[0021] The number of doors 36 is determined by the configuration of seam 26 of panel 18 , in particular, seam 26 serves to separate the instrument panel interface 18 into the two doors 29 which correspond to the doors 36 . The doors 36 are generally spaced apart along the centerline C of panel 18 to enable the air bag B to expand into the passenger area 10 after it has initially expanded into compartment 38 , as will be discussed in greater detail below. The doors 36 further include at least one aperture 44 for receipt of a protrusion 30 extending from inner surface 24 to couple doors 36 to inner surface 24 of panel 18 . However any appropriate alternative technique could be used to couple doors 36 to panel 18 . Doors 36 may be integrally formed about their outer periphery with compartment 38 and may include at least one flex rib 46 , thereby enabling doors 36 to flex outwardly to enable air bag B to expand into passenger area 10 .
[0022] The compartment 38 includes top and bottom walls 48 and 49 , respectively, coupled together via end walls 50 and 51 . Compartment 38 is formed such that end walls 50 and 51 diverge outwardly from each other as they extend from a rear aperture defined by rear edge 68 to front 66 of compartment 38 . One suitable configuration has a top view cross section of compartment 38 forming an isosceles trapezoid as shown in FIG. 2 . The top and bottom 48 , 49 , of compartment 38 are generally parallel to each other and approximately perpendicular to the end walls 50 , 51 . Generally, the base angle A at which end walls 50 , 51 diverge from rear side 68 can be between 91 and 180 degrees, but is more preferably within 95-128 degrees.
[0023] Base angle A of compartment 38 enables air bag B to enter the chute via the rear aperture and then preliminarily expand at least partially parallel to seam 26 within compartment 38 to a greater surface area prior to exiting panel 18 . Specifically, the greater the base angle A, the greater the area for the air bag B to expand, and this increase in surface area serves to more evenly distribute the force of the air bag B along seam 26 as it exits compartment 38 at panel 18 , while increasing a region in the passenger area 10 which is protected by the air bag B (as best shown in FIG. 4A ). Thus, the base angle A can be tuned to any desired angle, depending upon the vehicle, to increase the surface area of coverage and evenly distribute the force of the air bag B on deployment. Base angle A may be different at each end wall 50 , 51 in order to direct the air bag B into a desired expansion path for a given vehicle application.
[0024] A distance D separates doors 36 and generally corresponds with thickness T 1 of seam 26 in panel 18 .
[0025] As the air bag deploys, it will spread throughout the compartment 38 , and apply a substantially uniform force against seam 26 . The force will cause the doors 36 to flex outwardly, and simultaneously cause seam 26 to rupture, as shown in FIG. 4A . Once seam 26 fractures, doors 29 of panel 18 will flex outwardly to enable air bag B to expand into passenger area 10 and surround a passenger 100 , as illustrated in FIG. 4B .
[0026] Base angle A formed in compartment 38 of air bag chute 20 provides air bag B with a greater surface area within which to preliminarily expand in compartment 38 and also serves to more evenly distribute the force of the air bag B over a greater surface area. This even distribution of the expansion force reduces the force of air bag B as it exits compartment 38 , thereby protecting passengers which may be seated close to panel 18 .
[0027] The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. | A chute for receipt of a deploying air bag includes a compartment having first and second sidewalls extending laterally outwardly from a rear bag receiving aperture toward a front cover panel. The expanding volume of the chute enables a deploying air bag to outwardly expand at least partially parallel to a frangible seam in the front cover panel before the bag contacts the seam and ruptures it. As a result, the force of the bag is dispersed evenly along the seam to reduce maximum bag force exerted against the portion of the front cover panel located directly in front, or in the center, of the bag. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is the national stage entry of International Patent Application No. PCT/EP2010/007647, filed on Dec. 15, 2010, and claims priority to Application No. DE 10 2009 058 681.4, filed in the Federal Republic of Germany on Dec. 16, 2009.
FIELD OF INVENTION
[0002] The present invention relates to a balancing unit. It further relates to an external medical functional unit, and a treatment apparatus as well as methods.
BACKGROUND INFORMATION
[0003] European Patent No. EP 0 867 195 B1 describes balancing units for balancing mass and/or volume flows of medical fluids, such as blood or fluids used during the blood treatment.
SUMMARY
[0004] One object of the present invention is to propose a further balancing unit.
[0005] This object may be solved by a balancing unit for balancing medical fluids, in particular for balancing dialysate.
[0006] The balancing unit according to the present invention may comprise at least one balancing chamber and at least one conveying unit for filling the balancing chamber.
[0007] According to the present invention, the conveying unit may be a pressure controlled conveying unit or pressure limited conveying unit.
[0008] In all of the following embodiments, the use of the term “can be” or “can have” or “can comprise,” respectively, etc. is to be understood as a synonym for “preferably is” or “preferably has” or “preferably comprises,” respectively, etc.
[0009] The term “balancing” or “balancing process,” respectively, as used herein is, in one embodiment, to be understood as a comparison of masses and/or volumes of medical fluids supplied to or drawn from a patient or a treatment apparatus for treating the patient.
[0010] The term “patient” as used herein refers to a human or an animal, independently from being ill or healthy.
[0011] In the sense of the present invention, a “balancing chamber” refers to a unit or device, respectively, provided or intended to receive the medical fluids—or portions thereof—intended for balancing in an interior or inner volume, respectively.
[0012] In one embodiment according to the present invention, the balancing chamber is a chamber that is separated in at least two balancing chamber compartments or sections by means of at least one separating plate or membrane that can be designed displaceable or flexible. At least one of the balancing chamber compartments or sections can be provided or intended to receive supplied or fresh, respectively, medical fluids. At least one further balancing chamber compartment or one further balancing chamber section can be provided or intended to receive discharged or used, respectively, medical fluids.
[0013] The balancing unit can comprise more than one balancing chamber, i.e., e.g., two, three, four or more balancing chambers.
[0014] Several, e.g., two, balancing chambers can, for example, advantageously be used for ensuring a continuous flow of the medical fluids during the balancing process.
[0015] The balancing chambers can be in fluid communication or not. The balancing chambers can be fillable and/or dischargeable in common or separately.
[0016] Each balancing chamber can comprise (one or more) supply lines for supplied or fresh medical fluids and (one or more) drain lines connected with an outlet for discharged or used medical fluids. Shut-off valves may be arranged in the supply and/or drain lines.
[0017] Examples of such shut-off valves include actuators that can be retracted from and/or pushed into a part of a machine, such as a treatment apparatus. By means of these actuators, it can be possible to prevent or release a fluid flow within a fluid system of the medical fluids. Such actuators include actuators referred to as “phantom valves” as described in Application No. DE 10 2009 024 468.9, filed by the applicant of the present application in the Federal Republic of Germany on Jun. 10, 2009 and having the title “ Externe Funktionseinrichtung, Blutbehandlungsvorrichtung zum Aufnehmen einer erfindungsgemäβen externen Funktionseinrichtung, sowie Verfahren, ” which is expressly incorporated herein in its entirety by reference thereto.
[0018] Examples of balancing chambers according to one embodiment of the balancing unit of the present invention as well as their respective function are disclosed in the afore-mentioned European Patent No. EP 0 867 195 B1, filed by the applicant of the present invention and which is expressly incorporated herein in its entirety by reference thereto.
[0019] The conveying unit can be part of a fluid system in which the medical fluid is present or contained, respectively. The conveying unit can be built-in or switched into, respectively, the fluid system, e.g., for conveying the medical fluid. In or during its use, the conveying unit can be flowed through by the medical fluid to be balanced.
[0020] The fluid system can comprise lines, tubings, tubing systems, channels, chambers, indentations, units or devices, respectively, or spaces or areas for storing or retaining fluids as well as controlling devices for controlling or regulating a through-flow of the fluids, and the like.
[0021] In certain embodiments, the fluid system is provided for a dialyzing liquid.
[0022] In certain embodiments, the fluid system is provided for blood in an extracorporeal blood circuit or other fluids. Such other fluids comprise a citrate and/or calcium solution, water or a hydraulic liquid.
[0023] The pressure present in the balancing chamber upon filling is in the following referred to as filling pressure. It can be changeable. It can be increasing. It can have different values at different points of time.
[0024] In one embodiment, a maximum filling pressure of the balancing unit according to the present invention can be set by means of an adjusted rotation speed of the conveying unit. The maximum filling pressure can be predetermined by means of the characteristic curve of the conveying unit, e.g., a characteristic curve of a pump.
[0025] In one embodiment, the flow and/or the conveying pressure of the conveying unit is measured by using appropriate measuring units. Corresponding measuring units may be configured and provided therefor.
[0026] The maximum filling pressure for filling the balancing chamber of the balancing unit can be predetermined. In one embodiment according to the present invention, the maximum filling pressure can be set or is set, respectively, by changing the operating parameters of the conveying unit (e.g., by influencing the rotation speed of a pump).
[0027] In a further embodiment according to the present invention, the operating parameters of the conveying unit can be set or are set, respectively, (e.g., by influencing the rotation speed of a pump) by changing a magnetic field.
[0028] In one embodiment, the maximum filling pressure—after having been reached—can be maintained constant by the conveying unit for a certain time or can, in another embodiment, drop. This can happen depending on the preload.
[0029] The maximum filling pressure can, for example, be reached when the balancing chamber is substantially or completely filled by the one or more medical fluids to be balanced.
[0030] The maximum filling pressure can also be reached when a balancing chamber compartment or a balancing chamber section has been substantially or completely filled by operating the conveying unit.
[0031] In one embodiment of the balancing unit according to the present invention, the “pressure controlled conveying unit” or the “pressure limited conveying unit,” respectively, is a conveying unit that does not build up any higher pressure within the balancing chamber after having reached a maximum pressure or filling pressure.
[0032] In another embodiment of the balancing unit according to the present invention, the “pressure controlled conveying unit” or the “pressure limited conveying unit” is a pump, the impeller of which is overflowed by the fluid conveyed upon reaching the maximum filling pressure.
[0033] In a further embodiment of the balancing unit according to the present invention, the “pressure controlled conveying unit” is a conveying unit which can, in at least one operating state, be operated as a constant-pressure source or as a pressure source having a constant or approximately constant pressure.
[0034] In a further embodiment of the balancing unit according to the present invention, the “pressure controlled conveying unit” is a conveying unit comprising or consisting of at least one pump, wherein the pump does not comprise or is not functionally connected with any overflow valves and/or bypass lines.
[0035] In a further embodiment of the balancing unit according to the present invention, the “pressure controlled conveying unit” is a conveying unit which is not connected with a control unit for the purpose of controlling or limiting, respectively, the pressure of the conveying unit depending on the filling pressure present in a balancing chamber during filling the said balancing chamber and/or which does not comprise a control unit that is provided or intended for this purpose and configured correspondingly.
[0036] In a further embodiment of the balancing unit according to the present invention, the “pressure controlled conveying unit” is a pump that—due to its design or construction, respectively,—does not build up a pressure above a predetermined pressure—here the filling pressure. In at least one embodiment of the balancing unit according to the present invention, it is herein not—directly or indirectly, respectively,—assisted or supported, respectively, by any further elements or components, in particular no control unit, no switching mechanism, no valves, no bypass gauge pressure valves, no pressure measuring units, and the like.
[0037] If the balancing chamber filled by the conveying unit can be assumed to be a volume-fixed chamber after having reached a maximum pressure or filling pressure set by means of the machine, the conveying unit is called a “pressure controlled conveying unit” as is the case in one embodiment according to the present invention.
[0038] In one embodiment according to the present invention, the balancing unit comprises several conveying units.
[0039] In one embodiment according to the present invention, the balancing unit does not comprise any overflow valves, bypass lines, control units, switching mechanisms, valves, bypass gauge pressure valves, pressure measuring units, and the like, that are suited and provided or intended or configured for limiting the conveying pressure of the conveying unit.
[0040] In one embodiment according to the present invention, the balancing unit does not comprise a roller pump or a gear pump comprising a bypass valve and/or a pressure regulation.
[0041] If the balancing unit according to the present invention comprises several conveying units, the said conveying units could, in one embodiment, be designed in the same manner or differently.
[0042] In one embodiment according to the present invention of the balancing unit, the said balancing unit comprises several conveying units connected in series. In this way, it can advantageously be possible to disburden or unload, respectively, the balancing chamber in a controlled manner.
[0043] In one embodiment according to the present invention of the balancing unit, the single conveying units are arranged for running or being operated, respectively, in the same direction of conveyance or for conveying in the same direction, respectively.
[0044] In one embodiment according to the present invention, the conveying units run in different directions or convey in opposite directions, respectively. Hereby, it can advantageously be possible to build up pressure in a targeted manner and/or to limit the volume flow of the medical fluids. This can advantageously contribute to further reducing the forces acting on the balancing chamber. In particular, it can advantageously be possible to reduce or to even minimize the forces acting on the balancing chamber and the walls thereof.
[0045] In one embodiment according to the present invention, at least two conveying units run or convey, respectively, in the same direction. Hereby, it can advantageously be possible to reduce pressure in a targeted manner. This may also advantageously contribute to further reducing the forces acting on the balancing chamber (unloading the chamber). In particular, it can advantageously be possible to reduce or to even minimize the forces acting on the balancing chamber and the walls thereof.
[0046] In a further embodiment of the balancing unit according to the present invention, the “pressure controlled conveying unit” is a centrifugal pump, a pressure source, a membrane pump or a rotary pump.
[0047] In one embodiment, a “centrifugal pump” or a rotary pump can advantageously provide a high volume flow at low pressures and/or a low volume flow at high pressures.
[0048] In one embodiment according to the present invention, the centrifugal pump is an axial pump having the advantages known to a person skilled in the art in connection with axial pumps.
[0049] In a further embodiment according to the present invention, the centrifugal pump is a radial pump or a diagonal pump having the advantages known to a person skilled in the art in connection with radial pumps or diagonal pumps, respectively.
[0050] The maximum pressure of the centrifugal pump—and thus the maximum filling pressure—can be set by the rotation speed, e.g., by means of rotation speed control, such that the maximum pressure load on the entire system can advantageously be defined (highly) exactly.
[0051] The centrifugal pump can have the characteristic that an overflow of the impeller or of the rotational section, respectively, occurs above a certain fluid pressure, e.g., when the balancing chamber is completely filled. This overflow can result in a pressure control in the fluid conveyed such that the centrifugal pump operates in a pressure controlled manner in the sense of the present invention.
[0052] For achieving the pressure control the centrifugal pump does, in one embodiment, advantageously not require any assistance by further components, such as a control unit, a regulation unit, valves, etc.
[0053] According to the present invention, a pressure source is understood to be any fluid conveying apparatus the initial fluid pressure of which is constant or substantially constant.
[0054] By means of the incompressible pumped liquid or a corresponding fluid, the membrane pump generates exactly the pressure in the liquid or the fluid with which the membrane is operated or actuated, respectively (e.g., mechanically, electromagnetically, pneumatically or hydraulically). Thus, in a further embodiment of the present invention, a membrane pump is to be considered as a pressure source, in particular as a pressure controlled conveying unit.
[0055] In a further preferred embodiment, the conveying unit comprises at least one rotating section or rotational section, respectively. In one embodiment according to the present invention, the latter is supported by a mechanical bearing; in another embodiment, it is supported by a magnetic bearing.
[0056] The rotational section can exclusively or additionally be supported magnetically.
[0057] The rotational section can be arranged in an interior of the conveying unit.
[0058] In or during its use, the rotational section can be completely flushed by the medical fluids flowing through the conveying unit.
[0059] In one embodiment, the rotational section is an impeller or a rotor.
[0060] In a further embodiment, the conveying unit comprises at least one rotational section intended and designed for being actuated or operated magnetically by means of an external actuation or by means of an electrical field.
[0061] In a further embodiment, the external actuation of the rotational section is designed to be operated mechanically, e.g., by means of releasable fluid-tight couplings.
[0062] The term “external actuation” as used herein refers to an actuation for the rotational section that can be but does not have to be part of the balancing unit.
[0063] The external actuation can be arranged at an apparatus interacting with a balancing unit according to the present invention, such as a treatment apparatus. The external actuation can be part of the apparatus.
[0064] The magnetic driving or propelling, respectively, force or effect can by achieved by using one or more magnets. It can be achieved by using current-carrying conductors or live conductors, respectively. For example, live coils can be used.
[0065] In one embodiment according to the present invention of the balancing unit, the conveying unit is a magnetically supported centrifugal pump such as, for example, that described in European Patent Application No. EP 0 900 572 A1.
[0066] Such a magnetically supported centrifugal pump can—like every other magnetically supported conveying unit in the sense of the present invention—offer the advantage that a mechanical and/or electrical interface to the machine is not required and/or fluids do not have to be transferred from the machine or the treatment apparatus, respectively, to the pump.
[0067] In a further preferred embodiment, the medical fluid is selected from dialyzing liquid, blood, substituate liquid, drugs, drug preparations as well as mixtures or combinations thereof.
[0068] In one embodiment according to the present invention, in particular, balancing on the dialysate side during a dialysis is envisaged.
[0069] In one embodiment according to the present invention, balancing on the blood side during a dialysis is envisaged.
[0070] Further fluids that may be of interest and/or required for a balancing process in connection with a blood treatment of a patient include solutions or metabolites of the patient present in a solved form, such as, for example, substances obligatory excreted by urine, and the like.
[0071] In a further preferred embodiment, at least one first conveying unit is provided for conveying in a first direction. Further, there is provided at least one second conveying unit for conveying in a second direction opposite to the first direction.
[0072] The object of the present invention is further solved by an external medical functional unit. All advantages achievable by means of the balancing unit according to the present invention can in certain embodiments undiminishedly also be obtained by means of the external medical functional unit according to the present invention that comprises at least one balancing unit according to the present invention.
[0073] In one embodiment of the present invention, the external medical functional unit is embodied or designed as an external liquid circuit having a dialysate and an extracorporeal blood circuit or as a blood or dialysate cassette, respectively, or as a combined blood/dialysate cassette. The external medical functional unit may, e.g., be a blood or dialysate cassette, respectively, or a combined blood/dialysate cassette for dialysis.
[0074] In one embodiment according to the present invention, the external medical functional unit is a disposable unit, a single use article or a one-use product.
[0075] In one embodiment according to the present invention, the external medical functional unit is a disposable cassette.
[0076] The disposable cassette can be a solid or hard part. It can be made from a plastic material. The disposable cassette can be manufactured by using an injection molding method.
[0077] The object of the present invention is further solved by means of a treatment apparatus. All advantages achievable by means of the balancing unit according to the present invention can in certain embodiments undiminishedly also be obtained by means of the treatment apparatus according to the present invention.
[0078] The treatment apparatus according to the present invention is suited for treating medical fluids. It is designed to operate at least one balancing unit according to the present invention.
[0079] At least for this purpose, the treatment apparatus can comprise a control unit. The control unit can be or comprise a microprocessor.
[0080] In one preferred embodiment of the treatment apparatus according to the present invention, the treatment apparatus comprises a unit or device, respectively, provided or intended and configured for actuating the conveying unit of the balancing unit via a magnetic actuation interface.
[0081] The device or unit can, for example, be or comprise a magnet or a magnetic system and/or a live conductor such as, for example, one or more live coils.
[0082] The treatment apparatus can be connected functionally with a balancing unit according to the present invention and/or with an external medical functional unit according to the present invention.
[0083] In one embodiment according to the present invention, the treatment apparatus according to the present invention comprises at least one balancing unit according to the present invention.
[0084] In one embodiment according to the present invention, the treatment apparatus according to the present invention is firmly connected with the balancing unit according to the present invention.
[0085] In one embodiment according to the present invention, a repeated use of the firmly connected balancing unit according to the present invention is envisaged.
[0086] In one embodiment according to the present invention, the treatment apparatus according to the present invention is a hemodialysis device.
[0087] In certain embodiments, the treatment apparatus furthermore comprises further devices or units or is intended to be coupled therewith. Among those are, for example, an extracorporeal blood circuit, control devices for controlling the performance of a medical treatment, devices for monitoring and/or displaying a balancing process of the medical fluids used and/or circulated during a medical treatment, devices for displaying or representing states and/or parameters of the medical treatment or of the balancing process, such as screens, and the like, devices for operating or actuating, respectively, or controlling one or more components of the treatment apparatus, such as keypads, and the like, in order to, e.g., prompt the performance of a medical treatment, and the like.
[0088] In one embodiment according to the present invention, the treatment apparatus is a blood treatment apparatus.
[0089] Examples of blood treatment methods include dialysis methods such as a hemodialysis, in particular by using ultrafiltration, a hemodiafiltration, a peritoneal dialysis, an automatic peritoneal dialysis, and the like. For performing those methods, the blood treatment device can be designed or embodied correspondingly.
[0090] Finally, the balancing unit according to the present invention can be advantageously used in a peritoneal dialysis for determining the volume of the dialysis liquid that is directed into the peritoneal space of the patient and/or conveyed out of the patient therefrom. Thereby, for example, both balancing chamber compartments of a divided or bifid balancing chamber of the balancing unit can mutually be filled with fresh dialysis liquid (upon entrance of the dialysis liquid into the patient's abdomen) and/or with used dialysis liquid (upon removal of the dialysis liquid out of the patient's abdomen). The volumes and/or masses of the medical fluids, e.g., of the dialysis liquid, that are of interest during a balancing process can thereby, for example, be determined by the number of fillings of the balancing chamber.
[0091] The object of the present invention is further solved by a method. All advantages achievable by means of the balancing unit according to the present invention can undiminishedly also be obtained by the methods according to the present invention.
[0092] A method according to the present invention comprises balancing at least one medical fluid by using at least one balancing unit according to the present invention or at least one external medical functional unit according to the present invention or at least one treatment apparatus according to the present invention.
[0093] A method according to the present invention comprises filling a balancing chamber by means of at least one conveying unit and operating the conveying unit in at least one operating state as a constant-pressure source.
[0094] In order to operate the conveying unit in the desired operating state as a constant-pressure source, a certain rotation speed of the conveying unit can be set at which a fixed or definite, respectively, or predetermined pressure difference can be set in the conveying unit.
[0095] The present invention proposes a balancing unit in which the conveying unit can be operated as a constant-pressure source after filling the balancing chamber(s).
[0096] The constant-pressure source can advantageously contribute to ensuring a maximum filling pressure within the balancing chamber. The constructional requirements for the balancing chamber can thus be low.
[0097] Generally, the accuracy of a balancing process can primarily depend on the pressure variations between two filling procedures. This may result from the fact that the switching process for terminating a filling process is subject to minor variations and that the filling pressure or the pressure inside the chamber significantly increases at the end of the filling process.
[0098] Furthermore, it is known that a balancing chamber is usually not stable towards pressure. For this reason, its filling volume can change.
[0099] As the medical fluids introduced into the balancing chamber by means of the conveying unit can displace the fluids present in the balancing chamber to the same degree or with the same speed or rate, respectively, it can advantageously be possible to reach a constant or uniform mass and/or volume flow of the fluids to be balanced.
[0100] As a pressure difference for operating the balancing chamber can be set in an advantageously simple manner by means of the rotation speed and/or the maximum conveying pressure of the conveying unit, the pressure controlled conveying unit can set an advantageously precisely adjustable (also dynamically adjustable) balancing chamber pressure while balancing the medical fluids.
[0101] An adverse pressure increase and/or pressure variations of the balancing chamber can thus advantageously be prevented. An undesired volume expansion or change of the balancing chamber can thus advantageously be prevented.
[0102] In this way, it can advantageously be possible to improve a mass and/or volume accuracy of a balancing process.
[0103] This can, for example, also advantageously contribute to exactly determining the fluid volume that is drawn from a patient during a treatment, e.g., ultrafiltration during a dialysis treatment, via the dialysis filter membrane, and/or to set the said fluid volume onto the rate desired by the attending physician. The safety and optionally also the tolerance of a blood treatment can thus advantageously be further improved.
[0104] Thus, it can advantageously be possible to prevent an incorrect balancing wherein an incorrect balancing can add up, e.g., in the course of a blood treatment session. If the balancing influences the treatment performed, the balancing accuracy improved by means of the balancing unit according to the present invention in at least one embodiment can advantageously result in an improved and/or safer treatment, e.g., by setting the ultrafiltration rate in a more adequate manner.
[0105] The balancing chamber of the balancing unit according to the present invention can advantageously be used as a pressure controlled volumetric balancing chamber having sufficient stability.
[0106] Technically complex constructions such as strut members or reinforced plastic materials or the like, with which a sufficient stability has to be ensured in the state of the art, can advantageously be omitted when using the balancing unit according to the present invention. The construction of the balancing unit according to the present invention can thus advantageously be simplified due to the pressure control provided by means of the conveying unit.
[0107] Supporting walls of the balancing chamber at fixed structures of the treatment apparatus is not required. The usability of the balancing unit has thus become broader without losing its functional accuracy.
[0108] Additionally, the conveying unit in the balancing unit according to the present invention can advantageously do without using sensors and/or overflow valves and/or bypass gauge pressure valves, in particular for the purpose of limiting the pressure in an interior of the balancing chamber, and the like. Thus, it can further advantageously be possible to simplify operating the balancing unit. The conveying unit may be designed more simply.
[0109] In this way, the dimensions of the balancing unit or the required space for the balancing unit, respectively, can advantageously be kept small.
[0110] Due to the magnetic support of the conveying unit, the construction of the conveying unit can advantageously be simplified. Thus, it can advantageously be possible to omit mechanical components such as bearings and the like and to thus advantageously ensure little wear of the components and/or little abrasive wear. This advantageously allows avoiding or reducing a heating of the conveying unit or of the balancing unit.
[0111] Moreover, the conveying unit of the balancing unit according to the present invention can advantageously comprise little disposition for cavitation.
[0112] Another advantage can be only little noise development upon using the balancing unit according to the present invention.
[0113] Because the pressure of the conveying unit does not increase even with an ongoing volume flow after terminating the filling of the balancing chamber, it can advantageously be avoided having to shut down the conveying unit in case of a full, i.e. substantially or completely filled, balancing chamber. Thus, a fluid, e.g., flowing through the centrifugal pump, can overflow a rotational section of the centrifugal pump. In this way, a good rinseability (and flushability) of the conveying unit can be ensured with a directed flow within the space of the centrifugal pump in which fluid flows.
[0114] The magnetic actuation interface for operating the conveying unit or a rotational section thereof, respectively, can advantageously provide a contactless and/or seal-free actuation of the conveying unit. In this way, it can advantageously be possible to omit open interfaces between the balancing unit and the treatment apparatus.
[0115] It can thus advantageously be possible to ensure a particular safe operation of the balancing unit. An—albeit only extremely small—contamination risk of the medical fluids can thus advantageously be reduced and even completely excluded.
[0116] The balancing unit according to the present invention can advantageously be used as a disposable unit, i.e. as a one-way article for single use. As the conveying unit can be provided as an integral component of the disposable unit, it can be discarded together with the disposable unit such that the safety and the hygiene of a medical treatment can advantageously be further improved.
[0117] The use of centrifugal pumps has in certain embodiments the advantage of an inherent pressure control in case of an occlusion downstream the pump as compared to pressure-regulated peristaltic hose pumps, toothed gear pumps or peristaltic pumps. The pressure built up there can be adjusted by the rotation speed in a simple manner. A pressure-regulated peristaltic hose pump requires at least one pressure sensor comprising a control circuit; a peristaltic hose pump comprising a gauge pressure bypass valve has to be exactly calibrated to the allowed pressure. Thus, by using centrifugal pumps, the balancing unit according to the present invention is in certain embodiments less complex.
[0118] Exemplary embodiments of the present invention will be described with respect to the accompanying drawings. In the drawings, the same reference numerals denote same or identical elements or components, respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
[0119] FIG. 1 shows an exemplary balancing unit according to the present invention during a first cycle in a schematically simplified manner.
[0120] FIG. 2 shows an exemplary pressure curve plotted against the time during filling a balancing chamber.
[0121] FIG. 3 shows an exemplary pressure difference between the pump outlet and the pump inlet of a centrifugal pump plotted against the volume flow.
[0122] FIG. 4 shows the exemplary balancing unit according to the present invention of FIG. 1 during a second cycle in a schematically simplified manner.
[0123] FIG. 5 shows the exemplary balancing unit according to the present invention of FIG. 1 , comprising two further centrifugal pumps downstream the balancing chamber in a schematically simplified manner.
[0124] FIG. 6 shows the exemplary balancing unit according to the present invention comprising the balancing chamber, valves, and centrifugal pumps in a schematically simplified manner, wherein one of the centrifugal pumps arranged downstream rotates in another direction.
[0125] FIG. 7 shows an exemplary centrifugal pump comprising a magnetic support and a magnetic actuation in a schematically simplified manner.
[0126] FIG. 8 shows an exemplary treatment apparatus according to the present invention comprising a balancing unit and an external medical functional unit in a schematically simplified manner.
[0127] FIG. 9 shows an exemplary balancing unit according to the present invention in a further embodiment during a first cycle in a schematically simplified manner.
DETAILED DESCRIPTION
[0128] In the following, the balancing unit is exemplarily described as a part of a blood treatment apparatus for dialysis. It is intended to balance the dialysis liquid supplied to and drawn from a patient. However, it can in principle also be envisaged to balance the patient's blood.
[0129] FIG. 1 shows an exemplary balancing unit 100 according to the present invention comprising a balancing chamber 1 .
[0130] As shown in FIG. 1 , the balancing chamber 1 is separated or divided into a first balancing chamber compartment 3 a and into a second balancing chamber compartment 3 b. However, the balancing chamber does in principle not have to be divided in two balancing chamber compartments having substantially or completely the same size.
[0131] The first balancing chamber compartment 3 a is separated from the second balancing chamber compartment 3 b by means of a fluid-tight membrane 5 .
[0132] The first balancing chamber compartment 3 a is filled with a flow 7 a of a dialysis liquid via a tubing 9 a. A valve 11 a is thereby present in an opened position by means of a controlling unit 13 a.
[0133] The conveying unit can be a centrifugal pump. As shown in FIG. 1 , the first chamber compartment 3 a is filled by means of a centrifugal pump 15 a.
[0134] The valve 11 a can be designed as a tubing clamp (or generally as a squeezing mechanism). Such a tubing clamp can be opened and closed by means of an electrically controlled actuation. This has the advantage that the medical fluid substantially only contacts the tubing 9 a, but, however, does not contact parts of the valve 11 a or of the controlling unit 13 a. This can advantageously contribute to reducing a contamination risk of the medical fluids.
[0135] A second flow 7 b of the dialysis liquid is discharged out of the second balancing chamber compartment 3 b via a tubing 9 b. A valve 11 b is thereby also present in an opened position, mediated by means of a controlling unit 13 b.
[0136] The second balancing chamber compartment 3 b can be emptied. Discharging or draining dialysis liquid out of the second balancing chamber compartment 3 b can be effected at the same time as supplying or introducing dialysis liquid into the first balancing chamber compartment 3 a.
[0137] As shown in FIG. 1 , valves 11 c and 11 d are each closed by means of the corresponding controlling units 13 c and 13 d. There is no fluid conveyed in tubings 9 c and 9 d.
[0138] FIG. 2 shows a diagram representing an exemplary pressure curve or course 17 during filling a balancing chamber plotted against the time.
[0139] An initial pressure at t=0 corresponds to a pressure with which in FIG. 1 —which is in the following also referred to—the flow 7 a of the dialysis liquid is introduced into the first balancing chamber compartment 3 a via the tubing 9 a after opening the valve 11 a. In order to allow discharging flow 7 b of the dialysis liquid via tubing 9 b out of the second balancing chamber compartment 3 b, valve 11 b should be opened.
[0140] While the first balancing chamber compartment 3 a is filled and the second balancing chamber compartment 3 b is emptied, the pressure in the balancing chamber drops at first.
[0141] When the first balancing chamber compartment 3 a has been filled, the pressure rises. A final pressure 18 corresponding to the end point of the pressure course 17 during filling of the balancing chamber and thus corresponding to the maximum filling pressure can depend on the pressure applied by the centrifugal pump 15 a. This pressure can in turn depend on several parameters of the centrifugal pump, for example, on the construction principle of the centrifugal pump (radial pump, axial pump, diagonal pump, impeller shape, impeller diameter, etc.) and/or the set rotation speed of the centrifugal pump 15 a and thus the set operating point. Moreover, the final pressure can depend on the preload of the centrifugal pump 15 a, i.e., the pressure present at a dialysate inlet of the centrifugal pump 15 a.
[0142] FIG. 3 shows a diagram comprising an exemplary pressure difference ΔP between the pump outlet and the pump inlet of a centrifugal pump 15 a (ordinate) plotted against the volume flow Q of the medical fluids (abscissa).
[0143] At a characteristic curve 19 of an ideal pressure source which is indicated for comparison, the pressure difference ΔP is independent from the volume flow Q. The amount or extent, respectively, of the pressure difference ΔP depends, inter alia, on the set rotation speed of a centrifugal pump.
[0144] The actual pressure courses (ΔP, Q) usually divert from the ideal characteristic curve. A possible pressure course of a characteristic curve for a pressure controlled conveying unit such as the centrifugal pump 15 a of the balancing unit 100 according the present invention of FIG. 1 is shown by characteristic curve 21 of a centrifugal pump. It can be recognized that a good approximation of the pressure course to the ideal characteristic curve can be obtained by means of the centrifugal pump 15 a. FIG. 3 also shows that the centrifugal pump 15 a can be understood as a pressure controlled conveying unit in the sense of the present invention: Despite an increase of a volume flow, the pump outlet pressure does not increase anymore after having reached a certain pressure level.
[0145] FIG. 4 shows the exemplary balancing unit 100 of FIG. 1 during a second cycle. The second cycle can follow the first cycle according to FIG. 1 .
[0146] In the second cycle of a centrifugal pump 15 c, a flow 7 c of dialysis liquid is conveyed into the second chamber compartment 3 b via the tubing 9 c. At the same time, a flow 7 d of dialysis liquid is removed from the first chamber compartment 3 a.
[0147] FIG. 5 shows the exemplary balancing unit 100 of FIG. 1 comprising two additional centrifugal pumps 15 b and 15 d downstream the balancing chamber 1 .
[0148] All centrifugal pumps 15 a - d arranged in the balancing unit 100 according to the present invention of FIG. 5 convey in the same direction of conveyance as indicated by the arrow of the pump heads pointing to the left (related to the representation of FIG. 5 ).
[0149] By means of the centrifugal pumps 15 b and 15 d arranged downstream, emptying the two chamber compartments 3 a and 3 b can be supported. This can be advantageous in order to, for example, reduce or keep low a maximum pressure (see end point 18 of the curve of the pressure course in FIG. 2 ) in the balancing chamber 1 . Low pressures in the balancing chamber 1 can in turn advantageously contribute to simplifying the construction (such as, e.g., a lower stiffness, lower material thicknesses, etc.) of the balancing unit 100 as stated above. The latter could in particular be advantageous if the balancing unit 100 is embodied as a part of a disposable unit.
[0150] FIG. 6 shows the exemplary balancing unit 100 comprising the balancing chamber 1 similarly to FIG. 5 , however, with the difference that the centrifugal pump 15 b is provided or intended and configured for also running in another direction or conveying in the opposite direction, respectively, as indicated by means of the arrow of the pump head pointing to the left (related to the representation of FIG. 6 ).
[0151] When running in the opposite direction of rotation, the centrifugal pump 15 b operates as a pressure reducer, in particular as an adjustable pressure reducer.
[0152] In the embodiment of FIG. 6 , inlet and outlet of the centrifugal pump 15 b can be interchanged.
[0153] “Interchanging” inlet and outlet can be effected in different ways. Examples hereof are reversely inserting the centrifugal pump, providing valves correspondingly arranged and controlled, and the like.
[0154] Valves correspondingly arranged and controlled can be preferably operated by means of actuators of a dialysis machine across a flexible membrane, e.g., by squeezing and/or releasing the relevant fluid paths.
[0155] A reversion of the direction can be intended additionally or alternatively. The conveying units contemplated can be provided or intended and configured to be operated in one direction or in two directions opposite to each other.
[0156] FIG. 7 shows an exemplary centrifugal pump 15 a comprising an impeller 25 as a rotational section, a rotor 27 , coils 29 and a stator 31 . The centrifugal pump 15 a comprises a housing 32 having an inlet and an outlet (recognizable in FIG. 1 by means of arrows).
[0157] The centrifugal pump 15 a is flowed through in the flow direction shown. The actuation of the impeller 25 is performed by means of a circumferential electromagnetic field generated by controlling the coils 29 of the stator 31 .
[0158] Impeller magnets or at least ferromagnetic materials can be integrated into the impeller 25 .
[0159] The support of the impeller 25 can then, on the one hand, be carried out by means of the impeller magnets and, on the other hand, by means of magnets provided outside the centrifugal pump. The magnets can be arranged circumferentially in the same movement of rotation as the impeller 25 . Instead of the circumferential magnets or in addition hereto, also a circumferential electromagnetic field in a coil arrangement can support impeller 25 or fixate the said impeller 25 in a stable circumferential position, respectively. Though not shown in the figures, this embodiment is encompassed by the present invention as well.
[0160] FIG. 8 shows a balancing unit 100 according to the present invention and an exemplary treatment apparatus 300 according to the present invention comprising a dialyzer 33 comprising a blood inlet 33 a and a blood outlet 33 b as well as further elements or components, respectively, in a schematically simplified manner.
[0161] On the basis of FIG. 1 , FIG. 9 shows an exemplary balancing unit according to the present invention of a further embodiment during a first cycle in a schematically simplified manner. It can be recognized that the centrifugal pump 15 b conveys in a direction opposite to the direction of conveyance of the centrifugal pump 15 a. By means of the conveying units pumping in directions opposite to each other of this embodiment, a too high initial pressure can advantageously be prevented or reduced. This can be the case when the dialysate is produced from RO water (reverse osmosis water) and concentrates. In doing so, the RO water supply can have such a high line pressure that the balancing unit could be damaged thereby. | A balancing unit for medical fluids includes at least one balancing chamber and at least one conveying unit for filling the balancing chamber, in which the conveying unit is a pressure controlled conveying unit and/or is designed and provided for being operated in at least one operating state as a constant-pressure source. An external medical functional unit, a treatment apparatus and methods are also described. | 0 |
BACKGROUND OF INVENTION
[0001] This invention relates generally to educational devices. More specifically, the invention relates to reading, spelling, pronunciation and vocabulary educational devices, and many other creative uses.
[0002] Methods and devices for teaching or learning how to read are known in the art. These methods often provide a reference guide with keys to pronunciation using pictures to show how a letter or group of letters sounds. Some use question and answer methods. Others use a technique of lining up the word with a picture representing that word. Some devices have a movable slide or wheel that changes the letters so the user can form his own words. Still others have a mechanism that exposes an additional letter of a word with each move for a predetermined list of words.
[0003] The prior art devices and methods have their value, but none of them addresses the needs of a slightly more advanced reader. In addition, the prior art devices are often large, rigid and cumbersome. Many of them only have a limited number of available words to teach. As the user develops more reading ability, he “outgrows” many of the prior art devices. Other prior art devices prove frustrating to more advanced readers because they are too inconvenient to carry and use with more advanced reading materials. Therefore, what is needed is a new device and method that will allow a user with some reading skills to ascertain the pronunciation and meaning of unfamiliar words.
[0004] It is an object of the present invention to provide a tool to enable one to learn the pronunciation and meaning of words.
[0005] In accordance with this object, this invention is intended to provide a method of using a tool that isolates a portion of a word to enable one to look to familiar syllables and root words to learn the pronunciation, meaning and remember the spelling of words.
[0006] Still other objects, advantages, distinctions and alternative constructions and/or combinations of the invention will become more apparent from the following description with respect to the appended drawings. Similar components and assemblies are referred to in the various drawings with similar alphanumeric reference characters. This description should not be literally construed in limitation of the invention. Rather, the invention should be interpreted within the broad scope of the further appended claims.
SUMMARY OF THE INVENTION
[0007] The present invention provides a device, a kit and a method for helping an individual learn the pronunciation, spelling and meaning of a word. The device comprises a word isolator including a window and a slide. The window is placed over the unfamiliar word. The slide can cover the entire word, expose just a portion of the word, or expose the entire word. In practice, the user, when faced with an unfamiliar word, places the word isolator over the word with the slide fully covering the word. He gradually moves the slide to expose part of the word through the window. The user then uses his knowledge of individual letter sounds, such as consonants and vowels, and multiple letter sounds, such as consonant blends, diphthongs, prefixes and suffixes to determine the pronunciation of a syllable. Then he exposes the word, syllable by syllable, until the user can pronounce the unfamiliar word.
[0008] The present invention can also be used to help determine the meaning of an unfamiliar word. The user places the word isolator over the text with the slide moved so the root of the unfamiliar word is exposed in the window. The user ascertains the meaning of the root of the word, and then he adds the meaning of the prefix or suffix to the word to learn the meaning of the unfamiliar word. In the case of a compound word, the user can expose one word of the compound word at a time to understand the meaning of the whole word. Use of the word isolator may even encourage some students to read because, just when frustration sets in at finding an unfamiliar word, the student is empowered with a learning tool that appears to be a toy.
[0009] In addition, the present invention can be provided in a kit form. The user obtains a kit which includes the parts of the word isolator, in unassembled form. The parts may be pre-cut individual pieces, a perforated template, or a pre-printed template for cutting. The user then follows the directions to assemble and use the word isolator.
[0010] The present invention can be provided in pattern form. Once the pattern is provided, the user can make the word isolator out of any convenient material, in any quantity. Once traced from the pattern, the user can enlarge or shrink the tracing to customize the word isolator for his particular use.
[0011] The word isolator can be used in various sizes and types of books. Unlike any known prior art, the structure of the word isolator allows it to flex along the curve of the page of a book. One embodiment contains a flap that can be lifted to expose the entire window for large fonts, or folded partially down to create windows of various heights for words written in smaller fonts.
[0012] The word isolator can be used in learning games. For example, the word starts totally concealed. The teacher tells the students a category. The word is revealed one letter at a time until a student guesses the word. Another game could include covering one of the student's spelling words. The student says one letter at a time until the word is spelled correctly. If the student makes a mistake, he covers the word and starts again.
[0013] Additionally, the word isolator can be used in other subjects. For example, the answers to math problems can be covered with the slide, and uncovered after the student works the problem. Adults and children learning English as a second language can use this device to help master their new language. It can be used as a study aid for any kind of fill-in-the-blank type of worksheet. Once the student fills in the worksheet, he uses the word isolator to hide the answers during review and self study. The word isolator will encourage the student to study because of the positive reinforcement felt as he uncovers each correct answer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of the preferred embodiment of the word isolator with its slide shown within the window.
[0015] FIG. 2 is a template for the window portion of the preferred embodiment of the word isolator.
[0016] FIG. 3 is a template for the slide portion of the preferred embodiment of the word isolator.
[0017] FIG. 4 is a top view of the preferred embodiment of the word isolator shown exposing part of a word.
[0018] FIG. 5 is a top view of the preferred embodiment of the word isolator shown exposing the whole word.
[0019] FIG. 6 is a side view of the preferred embodiment of the word isolator along line 6 - 6 of FIG. 1 .
[0020] FIG. 7 is one embodiment of a template for a user assembled word isolator.
[0021] FIG. 8 is one embodiment of a pattern for use in creating multiple or custom sized word isolators.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] As shown in FIGS. 1-3 , the present invention may be formed from separable components referred to as the window portion 20 , and the slide portion 30 , which can be easily assembled with one another to form a completed construction. Window portion 20 includes slots 40 A and 40 B extending adjacent the top and bottom of an opening 35 A. The slide portion 30 has tabs 50 A and 50 B near a first end of the slide portion 30 , which tabs extend through slots 40 A and 40 B in the window portion 20 to secure the slide portion 30 and the window portion 20 to one another. A handle 60 is preferably provided near the second end of the slide portion 30 which extends from the window portion 20 .
[0023] FIGS. 2 and 3 show the separable components of the word isolator 10 . FIG. 2 shows a template for the window portion 20 of the word isolator 10 . Openings 35 A and 35 B are cut so they align with one another when the window portion 20 is folded along line 25 . Slots 40 A and 40 B are preferably cut so they are approximately equidistant from the opening 35 A. FIG. 3 shows a template for the slide of the word isolator 10 . To construct the word isolator, tabs 50 A and 50 B are folded at lines 55 A and 55 B, respectively and they are inserted into slots 40 A and 40 B, respectively, of window portion 20 . Then tabs 50 A and 50 B are folded down against the window portion 20 , creating a “wrapping” effect. Next, the window portion 20 is folded along line 25 , lining up openings 35 A and 35 B. Finally, the handle 60 is created by folding slide portion 30 at line 65 .
[0024] Use of the word isolator is shown in FIG. 4 . The slide portion 30 is placed inside the window portion 20 covering most of the unfamiliar word UNCOVERING. The letters UN show through the opening 35 , and the letters COVERING are masked by the slide portion 30 . The user first determines the sound of the letters in the first syllable UN, then he uncovers the next portion, COV and determines its pronunciation. He continues uncovering the syllables ER and ING until he determines the pronunciation of the entire word. The user also notes the meaning of the prefix UN, the root word COVER, and the suffix ING to learn the meaning of the word. FIG. 5 shows the entire word UNCOVERING exposed by the slide portion 30 in the opening 35 .
[0025] FIG. 6 shows a cross section of the word isolator looking along the line 6 - 6 of FIG. 1 . The window portion 20 is shown folded along line 25 . The handle 60 is shown folded up along line 65 . The tabs 50 A and 50 B are folded at lines 55 A and 55 B respectively and inserted into slots 40 A and 40 B respectively. Tabs 50 A and 50 B are then folded down and in towards the opening 35 A of the word portion 20 creating the “wrapping” effect referenced above.
[0026] FIG. 7 shows an embodiment of the present invention when provided in a template form. The template 60 includes the window portion 70 and the slide portion 90 with markings for the window cutouts 75 A and 75 B, the slots 80 A and 80 B for the slide portion flaps 95 A and 95 B, and the handle 100 . The template 60 may include perforated lines for easy removal of the pieces, or it may be pre-printed for cutting.
[0027] FIG. 8 shows an embodiment of the present invention when provided in pattern form. Once the pattern 110 is obtained, the user can make the word isolator out of any convenient material, in any quantity. After tracing an outline from the pattern 110 , the user can enlarge or shrink the tracing to customize the word isolator for his particular use. For example, a teacher would use a large word isolator at the chalk board for demonstration purposes, while the students use smaller ones at their desks. The word isolator could also be customized to accommodate various fonts as found in many early reading books.
[0028] The word isolator can be used in learning games. For example, the teacher starts with a word or an answer totally concealed. The teacher tells the students the category for the word, or asks a question. The word is revealed one letter at a time until a student guesses the correct answer. Another game could include covering one of the student's spelling words. The teacher points to a student and that student says the first or next letter of the spelling word. Play continues until the word is spelled correctly. The students could use the word isolator for independent play and study also. The student spells the word to himself uncovering one letter at a time. If the student makes a mistake, he covers the word and starts again.
[0029] Although the invention has been described in terms of specific embodiments and applications, persons skilled in the art can, in light of this teaching, can generate additional embodiments without exceeding the scope or departing from the spirit of the claimed invention. In addition, specific features of the invention are shown in some drawings and not in others for convenience only, as each feature may be combined with any or all of the other features in accordance with the invention. Accordingly, it is to be understood that the drawings and description in this disclosure are proffered to facilitate comprehension of the invention and should not be construed to limit the scope thereof. | An educational device and method in which a user can learn the pronunciation and meaning of words using a word isolator with a window and a slide. The word isolator is placed over the unfamiliar word. The slide is manipulated to expose only a portion of the word at a time, thereby helping the user break down and identify the unfamiliar word. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a frequency shift keyed demodulation system and, more particularly, to a system for demodulating continuous phase frequency shift keyed signals by recursively estimating the symbol values in a sequence.
Upon reception, a continuous phase frequency shift keyed signal is typically corrupted by white Gaussian noise and non-white interference. Discrete time samples of the sum of the signal of interest, noise and interference are produced by band limiting the received wave form, sampling at a rate satisfying the Nyquist criterion, complex heterodyning and filtering to pass positive frequency components and eliminate negative frequency components. In its simplest form, a demodulator can examine the received signal and choose as its output symbol that symbol which most closely corresponds with the received signal, independent of the value of any other previously received symbol. At the other extreme, a demodulator can examine every possible combination of symbols in a sequence and determine which combination most closely corresponds to the received multisymbol signal. The first of these demodulation techniques is relatively simple to implement but suffers from a relatively high symbol error rate. The other of the techniques has a low symbol error rate but is impractical to implement. It is therefore an object of the present invention to provide a demodulator for frequency shift keyed signals which results in a low symbol error rate and is practical to implement.
The most commonly utilized type of frequency shift keying is continuous phase frequency shift keying. The fact that the phase is continuous between adjacent symbols provides useful information. It is therefore another object of this invention to provide a demodulator which utilizes this continuous phase information.
SUMMARY OF THE INVENTION
The foregoing and additional objects are attained in accordance with the principles of this invention by providing a demodulator for a sequence of continuous phase frequency shift keyed symbols which utilizes a two pass symbol decision process. This two pass process consists of a forward and reverse pass, wherein a candidate symbol predecessor is recursively chosen for each symbol, according to a maximum likelihood decision criterion, on the forward pass. When a singular candidate predecessor is encountered, a reverse pass is initiated, so that a unique sequence of symbols is chosen back to a previously encountered singular predecessor.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing will be more readily apparent upon reading the following description in conjunction with the drawings wherein:
FIG. 1A and 1B together form a flow chart of a software implementation of this invention;
FIG. 2 is a block diagram showing the sufficient statistic computation;
FIG. 3 is a block diagram showing the bias terms computation;
FIG. 4 is a block diagram showing the demodulation process; and
FIG. 5 illustrates the two pass demodulation process according to this invention for an illustrative signal frame.
DETAILED DESCRIPTION
A continuous phase frequency shift keyed signal s(t) can be completely described by specifying the values of its analytic signal during the i th symbol period, as follows:
s.sub.i (t)=p(t-iτ) exp (j(ω.sub.1 (t-iτ)+φ.sub.i +θ)) (1)
where
t=time of observation, t≧0
i=symbol number, i≧0
τ=symbol duration
j=√-1
ω i =radian frequency of i th symbol
φ i =phase accumulated up to t=iτ due to modulation, with φ i =0
θ=initial phase at t=0
p(t)=amplitude modulation function, nonzero only for 0≦t<τ
Upon reception, s(t) is typically corrupted by white Gaussian noise and non-white interference. Discrete time samples of the analytic signal of the sum of the signal of interest (SOI), noise, and interference are produced by bandlimiting the received waveform, sampling at a rate satisfying the Nyquist criterion, complex heterodyning, and filtering to pass positive frequency components and eliminate negative frequency components. Following these operations, the resultant samples are given by:
r(kT)=s.sub.i (kT)+n(kT)+u(kT); k≧0 (2)
where
n(kT)=samples of analytic noise signal
u(kT)=samples of analytic interference signal
T=sampling interval
The maximum a posteriori (MAP) estimate of the i th symbol value is that value of ω i which maximizes the probability density of ω i conditioned upon a set of received samples. From Bayes' rule, that conditioned density is given by:
p(ω.sub.i |r)=p(r|ω.sub.i)p(ω.sub.i)/p(r) (3)
where
r is a N-vector comprising N samples of r(kT)
p(r|ω i ) is the conditional density of r, given that the i th symbol value=ω i
p(ω i ) is the probability that the i th symbol value=ω i
p(r) is the probability density of r
From equation (1) and the definition of φ i , which can be expressed as: ##EQU1## it is apparent that r is affected not only by ω i , but also by ω l , for all l<i. In fact, if samples of the i th symbol are located within r, when r is also affected by ω l , for l>i. Thus, one is led to a more powerful generalization of equation (3), wherein r is conditioned on a set Ω of symbol frequencies, and vice-versa:
p(Ω|r)=p(r|Ω)p(Ω)/p(r) (5)
The MAP estimate of Ω is that sequence of symbol frequencies which maximizes this expression. In general, however, such maximization requires exhaustive evaluation, which is impossible in the exact sense, since usually there is no means for truncating the length of r and limiting the size of Ω without compromising the theory. Even approximations wherein r and Ω are limited to relatively small sizes can result in prohibitive computation. For example, if the SOI modulation were quaternary, then to evaluate equation (5) for a sequence of only 50 symbols would require 4 50 ≃10 30 evaluations, which cannot be done in reasonable time with current technology.
This problem has been addressed, for example, in U.S. Pat. No. 4,096,442, to McRae et al. According to that patent, symbol estimates are based upon sequential groupings of three symbols. The present invention improves upon this particular aspect of the scheme of McRae et al, by performing recursive estimation of symbol sequences over sequence lengths with no inherent or practical limitations.
Continuing with equation (5), one can see that p(r) is independent of Ω, so that maximizing p(Ω|r) is equivalent to maximizing the likelihood function
λ.sub.Ω (r)=p(r|Ω)p(Ω) (6)
The vector r is now modeled as a complex Gaussian N-vector with means s.sub.Ω, which is an N-vector made up of samples s i (kT), i≧0, k≧0, Ω i εΩ, given by equation (1). Equation (6) can be expanded as
λ.sub.Ω (r|θ)=C.sub.1 exp [-1/2(r-s.sub.Ω).sup.T K.sup.-1 (r-S.sub.Ω)*]p(Ω) (7)
where C 1 is an inconsequential constant, the superscript T denotes matrix transposition, and the superscript * denotes complex conjugation. The N by N matrix K is the covariance matrix of noise plus interference. Note that it is conditioned upon knowledge of the initial phase λ.sub.Ω. Expansion of equation (7) results in
λ.sub.Ω (r|θ)=C, exp [-1/2(r.sup.T K.sup.-1 r*-2R.sub.e r.sup.T K.sup.-1 S*.sub.Ω +S.sup.T.sub.Ω K.sup.-1 S*.sub.Ω)]p(Ω) (8)
Since r T K -1 r* is dependent only upon r, and thus is independent of Ω, C 1 exp (-1/2 r T K -1 r *) can be replaced by C 2 , a second inconsequential constant. Also, since θ is in general unknown, it is modeled as being uniformly random in [0,2π], and the dependence upon θ is removed by noting that
λ.sub.Ω (r)=[ .sub.o.sup.2π λ.sub.Ω (r|θ)p(θ)dθ]p(Ω)=[C.sub.2 I.sub.o (|r.sup.T K.sup.-1 S*.sub.Ω |) exp (-1/2S.sub.Ω.sup.T K.sup.-1 S*.sub.Ω)]p(Ω) (9)
This expression can now be simplified by noting that maximizing λ.sub.Ω (r) is equivalent to maximizing its logarithm, and by discarding the constant ln C 2 , to obtain the log-likelihood function
Λ.sub.Ω (r)=[ln I.sub.0 (|r.sup.T K.sup.-1 s*.sub.Ω|)-1/2 s.sup.T.sub.Ω K.sup.-1 s*.sub.Ω ]+ln (p(Ω)) (10)
Here, and in equation (9), I 0 is the zeroth order Bessel function of imaginary argument.
The various operations in equation (10) can be interpreted in the following ways:
r T K -1 is a vector made up of input SOI plus noise plus interference samples r T , filtered by the inverse covariance K -1 to remove non-white interference.
|r T K -1 s*| is the correlation between the filtered signal r T K -1 and the SOI replica s.sub.Ω.
1/2 s.sub.Ω T K -1 s.sub.Ω * is a so-called bias term which compensates for the effects of the filter K -1 upon the SOI component of r T .
The MAP symbol sequence is determined by the set Ω which maximizes Λ.sub.Ω (r).
As was stated previously, an exact implementation of equation (10) is in general impossible, the dimensions of r, K, s, and Ω being prohibitively large or even unbounded. The present invention relies upon a recursive scheme to approximate an implementation of equation (10).
Derivation of the recursive approximation is begun by rewriting the second term in equation (10) as follows: ##EQU2## where S.sub.Ω is an N-vector comprising samples of the spectrum of s.sub.Ω
P -1 is the frequency-domain equivalent of K -1 .
P -1 is an NxN diagonal matrix.
P -1 (n) is the n th diagonal element of P -1
S i (n) is the n th sample of the spectrum of s i
In its current embodiment, the invention utilizes this frequency-domain implementation to compute the demodulator bias terms.
The first term in equation (10) is now simplified by noting that s.sub.Ω can be written as a sum over i of s i (kt) as defined in equation (1): ##EQU3## Here, the notation ##EQU4## denotes an N-vector consisting of samples of the SOI taken from and aligned with the i th symbol, and zeros elsewhere. The time index k begins at k=L i-1 +1 and ends at k=L i , so that the nonzero portion of the vector has length L i -L i-1 . In general, this length is variable unless sampling is synchronous with the SOI symbols. The parameter I in equation (12) is the number of symbols contained in s/TΩ.
Let v denote the N-vector r T K -1 . This vector is assumed to be computed externally to the FSK demodulator, and provided as the demodulator's primary input signal. Let v k denote the k th element of v. With this definition and that of equation (12), the term r T K -1 s*.sub.Ω of equation (10) can be written ##EQU5## The last equality follows from an explicit expression of s (kT) as given in equation (1). A slight rearrangement results in ##EQU6##
Values of the second summation can be computed for each i and candidate ω i , independently of φ i and θ, and then combined as indicated by the summation over i. These values must be computed for each possible value of ω i so as to maximize the likelihood function. Let the possible values of ω i be denoted as ωi,1, ω i ,2, . . . , ω i ,μ.sbsb.i so that at the i th symbol, there are μ i possible frequencies. Clearly, μ i ≧1. However, there is no fundamental upper limit on μ i . In fact, the modulation frequency can take on a continuum of values between a lower and upper limit; in this case, μ i must simply be chosen with a sufficiently large value to provide acceptably fine quantization of the estimate of ω i .
Let ##EQU7## The values of γ i ,l are the so-called sufficient statistics of v. From equations (15), (14), (13), (11), and (10), the likelihood function can now be written as ##EQU8## where b i ,l denotes the bias component corresponding to ω i ,l, computed as indicated in equation (11): ##EQU9## In equation (16), the dependence of Λ upon ω i ,l for 0≦i<I, is denoted explicitly with the subscripts I,l. The second phase term, φ i , is implicitly dependent upon frequency sequences preceding the i th symbol. Also, note that the argument of I o in that equation is independent of θ, due to the absolute value, as it should be.
A recursive scheme for approximating the frequency sequence which maximizes Λ is now presented. This scheme is developed as follows: Let Γ i-1 ,m, m=1, 2, . . . , μ i-1 , denote a sufficient statistic accumulated up to the (i-1) th symbol, and corresponding to ω i-1 ,m. That is, ##EQU10## For k=i-1 in this summation, l=m, but values of l for k<i-1 are as yet unspecified. Similarly, let B i-1 ,m, m=1, 2, . . . , μ i-1 , denote the corresponding accumulation bias terms, so that ##EQU11## For each k in this summation, the value of l is the same as that taken in equation (18), so that Γ i-1 ,m and B i-1 ,m correspond to the same sequence of symbol values.
A method is now needed for transitioning from symbol i-1 to symbol i in some "best" manner. The clear choice is to choose the transition so as to maximize the likelihood function of equation (16). Thus, for each l=1, 2, . . . , μ i ,Γ i-l and B i ,l are chosen such that
Γ.sub.i,l =Γ.sub.i-1,m +exp (-jΦ.sub.i-1,m) Γ.sub.i,l (20)
and
B.sub.i,l =B.sub.i-1,m +b.sub.i,l (21)
maximize the value of
Λ.sub.i,l (r)=ln I.sub.o (|Γ.sub.i,l |)-1/2B.sub.i,l (22)
over m. In equation (20), φ i-1 ,m is the phase accumulated through symbol i-1 corresponding to the symbol value sequence implicit in the summation expression (equation (18)) for Γ i-1 ,m. Thus, ##EQU12## with the l's in this sum corresponding to those used in equation (18) for Γ i-1 ,m.
This step-by-step maximization procedure results in choosing a most likely predecessor symbol value ω i-1 ,m for each possible symbol value ω i ,l of the current symbol. It also serves to prevent the exponential growth of possible symbol value sequences which occurs if all possible values of Γ, B, and φ are computed. Initialization of the procedure is achieved by either setting starting values of Γ, B, and φ to zero, or to known values if they are available for some symbol.
In the notation below,
φ i ,m is the phase accumulated up to but not including the i th symbol, and corresponding to ω i-1 ,m
Γ i ,l is the sufficient statistic accumulated, in a phase-continuous manner, up to and including and i th symbol, and corresponding to ω i ,l (and, consequently, to γ i ,l)
B i ,l is the bias accumulated up to and including the i th symbol, and corresponding to ω i ,l (and, consequently, to b i ,l)
Γ i ,l and B i ,l are the values of Γ i ,l and B i ,l respectively, which maximize Λ i ,l over all possible values of ω i-1 ,m for each l
Δ i ,l is a vector of candidate predecessors of ω i ,l
ω i ,l is the estimated symbol frequency sequence.
This sequence constitutes the demodulator output.
Initialization
Γ o ,l =γ o ,l ; l=1,2, . . . ,μ o
B o ,l =b o ,l ; l=1,2, . . . , μ o
φ o ,m =ω o ,m τ; m=1,2, . . . , μ o
i=1
J=1
Recursion
Procedure P1
Step P1a: l=1
Step P1b: Λ max=0
Procedure P2
Step P2a: m=1
Step P2b: Λ=ln I O (|Γ i-1 ,m +exp (-jφ i-1 ,m)γ i ,l |)-1/2(B i-1 ,m +b i ,l)
Step P2c: If Λ>Λ max or m=1 then execute Procedure P3, else go to Step P2d
Procedure P3
Step P3a: Λ max =Λ
Step P3b: Γ i ,l =Γ i-1 ,m +exp (-jφ i-1 ,m)γ i ,l
Step P3c: B i ,l =B i-1 ,m +b i ,l
Step P3d: φ i ,l =φ i-1 ,m +ω i ,l τ
Step P3e: M=m
End Procedure P3
Step P2d m=m+1
Step P2e: If m≦μ i-1 then go to Step P2b
End Procedure P2
Step P1c: Δ i ,l =M
Step P1d: l=l+1
Step P1e: If l≦μ i then go to Step P1b
Step P1f: If Δ i ,l =Δ i ,1 for 1≦l≦μ i then execute Procedure P4, else go to Step P1g
Procedure P4
Step P4a: l=i
Step P4b: m=1
Step p4c: M=Δ l ,m
Step P4d: ω l-1 =ω l-1 ,m
Step P4e: m=M
Step P4f: l=l-1
Step P4g: if l≧J then go to Step P4c
Step P4h: J=i+1
End Procedure P4
Procedure P5
Step P5a: m=Δ i ,1
Step P5b; l=1
Step P5c: φ i ,l =ω i-1 τ+ω i ,l τ
Step P5d: Γ i ,l =γ i-1 ,m +exp (-jφ i ,l)γi,l
Step P5e: B i ,l =b i-1 ,m +b i ,l
Step P5f: l=l+1
Step P5g: If l≦μ i then go to Step P5c
End Procedure P5
Step P1g: i=i+1
Step P1h: go to Step P1a
End Procedure P1
The foregoing is shown as the flowchart of FIGS. 1A and 1B.
Step P1f is a test to determine whether all possible symbol frequencies at the i th symbol share a common predecessor. If that is the case, then Procedure P4 is invoked to select that singular predecessor as ω i-1 , the singular predecessor of ω i-1 as ω i-2 , etc., back to the previous singular predecessor, the position of which is tagged by J. An alternative embodiment is possible whenever it is known that once every L symbols, the symbol frequency is fixed at a known value, that is,
μ kL =1, and ω kL is known, for k an integer. In that case, Step P1f is replaced by the following:
Step P1f': If i=kL, for k an integer, then execute Procedure P4, else go to Step P1g
Procedure P5 serves to reset the recursion so as to avoid an unlimited propagation of errors in the accumulated values.
In its present embodiment, the invention is implemented in a FORTRAN computer software subroutine. Primary inputs to the subroutine consist of the following:
(1) A filtered input signal
(2) Filter coefficients
(3) A description of the modulation structure of the SOI
(4) An SOI symbol synchronization signal
(5) An SOI frame synchronization signal
(6) The SOI amplitude
(7) The noise power
The primary output of the subroutine is the estimated symbol frequency sequence.
The demodulator first computes a set of sufficient statistics from the filtered input signal (see FIG. 2). This signal, which is input as a set of spectral samples, is first inverse fast Fourier transformed (101), and then an inverse window is applied (102) if appropriate. A table of sufficient statistics is then computed by correlating (103) the time-domain signal samples with locally generated (104) symbol replicas. The sufficient statistics are stored in memory (105).
The second process carried out by the demodulator is that of bias term computation (see FIG. 3). From the description of the SOI modulation structure, the power spectrum of each possible symbol is computed (201) and correlated (202) with the filter coefficients. These correlation results are multiplied by -1/2 (203) and stored in memory (204). Bias terms are updated only once each block, where a block consists of a number (typically 4096) of processed signal samples.
Computed values of bias terms and sufficient statistics serve as input to the demodulation loop (FIG. 4). In the current embodiment, the demodulator assumes a fixed-frequency framing symbol spanning symbol periods 39 and 40, 79 and 80, 119 and 120, itc., and data symbols elsewhere. Thus, a sequence of candidate symbol predecessors is accumulated over 38 data symbols, and then, at the framing symbol, which is at a fixed, known frequency, a singular predecessor naturally occurs, and a set of symbol estimates is selected back to the previous framing symbol. FIG. 5 depicts the process for a single frame consisting of 9 data symbols and 1 framing symbol. The modulation structure depicted is as follows:
______________________________________ Symbol No. Modulation______________________________________0 (frame symbol) invariant1 binary2 quaternary3 invariant4 analog5 octal6 binary7 binary8 invariant9 quaternary10 (frame symbol) invariant______________________________________
Note that the analog symbol (No. 4) is depicted as being quantized to 17 levels. The light arrows in FIG. 5 illustrate the set of candidate predecessors chosen on the forward pass; the heavy line shows the estimated sequence chosen on the reverse pass after Symbol 10 is encountered.
At each symbol time (the "current" symbol), a most likely predecessor value is chosen for each possible value of the current symbol frequency. Thus, at each symbol, two loops are invoked; the outer loop corresponds to each possible frequency of the current symbol, while the inner loop corresponds to each possible frequency of the preceding symbol.
As shown in FIG. 4, memory locations are reserved for the phase (301), sufficient statistic sum (302), and bias sum (303) accumulated up through the predecessor symbol. The proper values are selected by way of the inner loop counter (304). Sufficient statistics and bias terms are selected for the current symbol by the outer loop counter (305). Likelihood functions are computed in 306 and, if a likelihood function is larger than the previous maximum (or upon the first iteration of the inner loop) the values of the likelihood function and current sufficient statistic and bias sums are saved (307). Upon exit from the inner loop, the phase, sufficient statistic, and bias sums are updated (301, 302, 303) to correspond to the maximum likelihood. The predecessor value corresponding to the maximum likelihood is also saved (308). This process continues until the framing symbol is encountered, at which time the reverse pass algorithm (309) is invoked, the resulting symbol value estimates are output, and the sufficient statistic, bias, and phase sums are reset to those of the framing symbol.
The reverse pass algorithm selects the single predecessor of the most recent framing symbol, then selects the predecessor of the predecessor, etc., back to the previous framing symbol. The sequence of predecessors forms the output symbol value sequence.
Accordingly, there has been disclosed a recursive frequency shift keyed demodulation system. It is understood that the above-described embodiment is merely illustrative of the application of the principles of this invention. Numerous other embodiments may be devised by those skilled in the art without departing from the spirit and scope of this invention, as defined by the appended claims. | A demodulator for continuous phase frequency shift keyed signals is implemented through the medium of computer software and processes incoming signals which are initially passed through an interference reduction filter. The disclosed demodulation algorithm makes use of the fact that the phase is continuous between adjacent symbols, as well as other symbol to symbol correlations, to reduce the error rate by processing a string of symbols utilizing a two step symbol decision process, instead of merely demodulating a symbol from a time slice of the received signal. The two step symbol decision process consists of a forward and reverse pass, wherein a candidate symbol predecessor is recursively chosen for each symbol, according to a maximum likelihood decision criterion, on the forward pass. Once a singular candidate predecessor is encountered, a reverse pass is initiated, so that a unique sequence of symbols is chosen back to a previously encountered singular predecessor. | 7 |
FIELD OF THE INVENTION
The invention pertains to the field of surround sound. More particularly, the invention pertains to circuits used to encode or decode "presence" or "surround" information in stereo audio sources.
BACKGROUND OF THE INVENTION
In the average movie theater, two types of "surround" systems are used-the 70 mm 6-track magnetic system, and the more common 35 mm optical arrangement. The former uses a magnetic strip attached to the film to supply six discrete channels, and the latter uses two optical audio tracks. This two-channel system is the basis for home surround sound decoders.
Every stereo videodisc, tape and MTS broadcast that was surround encoded still contains the same rear channel information as the two-channel magnetic master from which the theatrical 35 mm optical soundtrack was produced. In other words, your stereo videotape or disc of Star Trek I, II, II, Raiders of the Lost Ark, Superman and Star Wars can be decoded to produce surround sound at home. In addition, LPs, CDs and any stereo audio material can benefit from surround sound decoding. Ambiance extraction is a pleasant side effect that many decoders provide. In a nutshell, if the recording was made in a large hall, or a small club, "surround sound" will reproduce the recording environment faithfully.
Assuming the listener is seated centered between the two speakers, sound which is recorded "in phase" and with equal amplitude in each channel in a standard stereo system will appear to the listener to be located equidistant between the two speakers, as the two in-phase audio signals add together. The sound can be shifted left-to-right by varying the ratio of the amplitude of the left and right signals.
"Out of phase" signals, on the other hand, tend to cancel each other out. If a signal is recorded at equal amplitude on each channel of the stereo but 180°out of phase, the listener would ideally hear nothing, as the two signals cancel each other out. As a practical matter, the signals are audible, but sound odd.
By subtracting the left and right signals (L-R), the in-phase signals will be cancelled, and the out-of-phase signals are recovered. This is the basis of the "matrix encoding" which is used to record surround information which is inaudible to listeners with conventional stereo equipment.
"Dolby Surround", a proprietary technique of Dolby Laboratories, inc., is the current standard for multi-channel movie sound. The Hollywood mixers start with a conventional stereo soundtrack, which has one left channel and one right. By using some of Mr. Dolby's black boxes, they drop in two more "matrix"-encoded channels--one for the front center channel (used mainly for dialogue), and one for the rear surround channel (used mainly for effects). The rear-channel sound information is mixed "out-of-phase" into both stereo channels ("left-minus-right"), and the center-channel information is derived from the information common to both stereo channels ("left-plus-right").
The center and surround channels must then be decoded from the encoded stereo signal. The center and rear (surround) signals are then reproduced on speakers located between the normal front stereo speakers and behind the listener, respectively.
There are many surround sound decoders on the market today. The simplest of them is the Dynaco model QD-1, which is a version of the decoder described in a 1970 Audio Magazine article by David Hafler for use with the then-emerging quadrophonic sound technology (which has since been abandoned). Hafler's U.S. Pat. No. 3,697,692 is essentially the same as the Dynaco QD-1. The Hafler system operates at high levels - that is, the speaker output from the left and right amplifiers is divided among the four speakers, with the (L+R) center speaker connected between the "-" terminal of the L and R speaker and ground, and the (L-R) rear speaker connected across the "+" terminals of the L and R speakers.
Ranga, U.S. Pat. No. 4,132,859, is another high-level system, which is a further development of the Hafler system.
Very good results can be obtained with the Hafler system. However, all high-level systems have a number of basic problems, not the least of which being the expense of using high-power components (L-Pads) to balance the system. Also, the balance controls on the amplifier must be carefully set, using a mono signal, for minimum surround channel output, and then left strictly alone. Any change in the amplifier balance destroys the surround effect.
Most surround decoders currently on the market operate at "line level". That is, they take the left and right signals at preamp level, before they are fed into the final amplifiers. This requires a second set of amplifiers for the two derived channels, but eliminates the need to deal with the power requirements of a high-level decoder. Since the surround channel signals are decoded at constant preamp level, the balance controls on the amplifier (after the decoding) have no effect on the decoding.
All of the low-level decoders known to the inventor use active components (transistors, operational amplifiers, etc.) to decode the surround information from the stereo source. The original decoders were primarily analog circuits, such as may be seen in Holbrook, U.S. Pat. No. 4,612,663, Ito, et.al. (Sansui), U.S. Pat. No. 3,757,047, or Iida (Sony), U.S. Pat. No. 3,725,586. Other low-level active analog systems are Ohta, et. al. (Victor of Japan), U.S. Pat. No. 3,745,254 (using frequency-dependent phasing), Ito, et. al, (Sansui) U.S. Pat. No. 3,761,631 (phase modulates rear channels at an ultra-low frequency rate).
More modern higher-end units today tend to use digital signal processing to achieve the same results. Various kinds of filtering, noise reduction, reverberation, and other effects are often built into these units. All of this adds to the expense and complexity of the decoders. For example, the SONY TAE-1000ESD Surround-sound Processor/pre-amp lists for approximately $1000, and offers a wealth of digital-processing modes, including one of the finest overall surround-sound decoders available; the LEXICON CP-1 Surround-sound Decoder lists for $1250, and has true Dolby Pro-Logic Surround circuitry, 16-bit digital delay, two audio/video inputs, and a full-function wireless remote control. The CP-1 also features an "auto azimuth correction" mode designed specifically to prevent dialogue from leaking into the rear channel, and a number of digital signal processing effects modes.
All of these active decoding systems, especially the digital ones, involve complicated and expensive electronics, and relatively high prices.
The Dolby Surround System introduces a digital delay into the surround (rear) channel. There are several reasons advanced for this. One is to delay the rear signal so that the front and rear signals arrive at the listener's ears at the same time. This would appear to be a poor technique, since it would depend entirely on where the listener sits relative to the two sets of speaker. Others suggest that the "Haas effect" causes a listener to localize sound to the direction it is heard first. By delaying the rear sound by a fixed amount, usually 20 milliseconds, the listener is tricked into hearing the sounds as being primarily front/center, and the effect of stray sounds being erroneously shifted to the rear is minimized. Some units add a variable delay control, which allows the user to change the length of the fixed delay, but whatever the user chooses, the delay remains fixed at whatever the chosen length is.
Twenty milliseconds is the period of one cycle at a frequency of 50 Hz. This means that the only sounds which are correctly phased with a 20 ms delay system are those which are even multiples (harmonics) of 50 Hz. All others are to a greater or lesser degree out of phase. Frequencies between the peaks can be greatly attenuated or cancelled completely due to out-of-phase mixing. This creates a situation which is every audio engineer's nightmare--an overall system response with a peak in every octave, caused by speakers which are in phase only near certain frequencies. It is advantageous, then, to eliminate the use of delays in the surround sound decoding.
SUMMARY OF THE INVENTION
The invention presents a passive circuit for surround-sound decoding using a transformer having center-tapped primary and secondary windings. The line level left and right signals are introduced into the primary winding, and the center tap of the primary supplies a left-plus-right center channel output. The secondary center tap is grounded, and the winding connections supply left-minus-right and right-minus-left surround outputs.
The same circuit can be used for recording surround sound onto a two-channel (stereo) medium. A center microphone is connected to the center tap of the primary winding. Left and right surround microphones are connected to the secondary winding, which has its center tap grounded. The left and right recorder inputs are connected to the opposite sides of the primary winding.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a block diagram of the circuit in use.
FIG. 2 shows a schematic of the circuit of the invention.
FIG. 3 shows the circuit in use to record surround sound.
FIG. 4 shows an alternative connection of the circuit as used to record surround sound.
FIG. 5 shows the circuit as used to modify or create surround sound on recordings which were not originally recorded with the surround information.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 2 shows the circuit of the invention. As can be seen from that figure, the basic element of the circuit is an audio transformer (38) which has primary (42) and secondary (43) windings. Each of the windings is equipped with connections at each end: (39) and (41) on the primary, and (44) and (46) on the secondary windings. Each winding also has a center tap connection midway between the end connections: (40) on the primary and (45) on the secondary.
The transformer can be any audio type having suitable impedance characteristics for the application. For the typical preamp input/output situation with current technology audio equipment, it would be recognized by one skilled in the art that input impedances in excess of 1KΩ, and outputs at or below 1KΩ would be appropriate. Other applications, or changes in standards in the future, might require other impedance ranges, which would be within the ability of one skilled in the art to select.
Because the circuit operates at low power levels (that is, at the preamp input levels rather than amplifier output levels) it is preferred to use a small, low power transformer for economic and space reasons.
The preferred embodiment of the invention uses a transformer having a primary (input) winding of 10KΩ impedance (5KΩ each side of center tap) and a secondary winding of 2KΩ impedance (1KΩ each side of center tap). Such a transformer may be purchased from Triad, selected from series number SP-21, which is a series of small transformers, specifically model TF5S21ZZ.
Since low bass sounds are essentially non-directional, there is no need to pass these frequencies through to the surround channels. Therefore, the preferred transformer has frequency characteristics which are flat above 300 Hz, and which roll off -3 dB at 200 Hz, and essentially cut off frequencies below 100 Hz.
The right (30) and left (31) channels of the stereo signal having the out-of-phase surround information is supplied to the primary of the transformer at the end connections (39) and (41), respectively. To make the connections to the audio equipment easier, left (32) and right (33) front outputs are connected directly to these inputs, so that the front channel sound information can be taken from the source, "looped" through the box containing the circuit of the invention, and routed to the inputs of the front channel amplifier. It will be understood that these outputs can be dispensed with, if the outputs of the signal source are connected to the circuit and the front amplifier using "Y" patch cords to parallel the inputs.
If desired, a number of input connectors can be provided, for multiple signal sources such as VCR's, CD players, stereo or TV tuners, etc. In such cases a double-pole multi-throw switch would be included to switch left/right input pairs to the left (30) and right (31) inputs to the circuit.
Ganged potentiometers (47a) (47b) may be included as system master volume control to control overall level of the the front and center/rear (surround) speakers. The potentiometers are tapped (48) at 40% from the grounded end, and a 2.2KΩ resistor (49) and 0.047 μf capacitor (80) is in series to ground to provide a loudness compensation. The capacitor (80) is shorted by switch (81) to defeat the loudness compensation.
The center tap (40) of the primary winding (42) supplies the in-phase sum of the two input signals (Left+Right) to a center channel output (36). Since this center tap is connected through the primary winding to the left and right inputs at the ends of the primary winding, the center channel output (36) has DC continuity with the two input channels. In other words, the 100 Hz cut-off does not apply to the center channel signal. Thus, the center output (36) may be paralleled with a sub-bass output (37), which can be used to drive a sub-woofer amplifier. Since sub-bass audio is non-directional, only one sub-woofer speaker on the L+R signal is required, rather than separate Left and Right Sub-woofers.
The secondary winding (43) supplies difference signals (L-R) and (R-L) for driving Left Rear (34) and Right Rear (46) outputs from the end connections (35) and (46), respectively. These two outputs are identical, but 180°out of phase with each other. The center tap (45) of the secondary winding (43) is grounded.
This difference signal extracts the out of phase surround information from the Right and Left input signals, and the sum signal cancels the surround information and passes the in-phase front channel information.
That is, if a sound source is to appear in center front, it is mixed by the film audio editors equally, in phase, to the left and right channels. If the signal is denoted as "X" then X+X (the L+R center channel)=2X. On the other hand, X-X (the L-R rear surround channel)=0, or no signal.
If a sound source is to appear only in the rear (surround) speaker(s), it is mixed, out of phase, equally onto the left (L) and right (R) signals - i.e. X to the left channel and -X to the right (or vice versa). Then, the center channel (L+R) will have no signal: X+(-X)=0. The rear (surround) channels (R-L) and (L-R), however will have the signal reproduced: X-(-X)=2X, and (-X)-X=(-2X).
FIG. 1 shows how the circuit of the invention is used in a surround-sound home theater system. The system comprises a stereo TV set (1) used for display of the TV picture and for amplification of the front channel audio, a tuner/vcr (2) which supplies the video and audio signals for the system, the surround decoder of the invention (3) and a stereo amplifier (4), used to amplify the surround and center channel audio.
In the preferred embodiment shown, five speakers are used: left (6) and right (7) front, center (8) and left (9) and right (10) rear/surround. They are shown as they would be placed around the listener (5). The center (8) speaker would normally be put facing the listener (5) either immediately above or below the TV screen. The front left (6) and right (7) speakers would flank the TV screen, perhaps 6 feet or so apart, facing the listener (5). The surround speakers (9) and (10) are behind the listener (5), preferably facing inwards.
The video output (13) of the tuner/vcr (2) is connected to the video input (12) of the stereo TV (1). The left and right (17) audio outputs of the tuner/VCR are fed into the decoder (3), and "loop" through to the audio inputs (14) of the stereo TV (1) which then drives the left (6) and right (7) front speakers from its left (11) and right (16) speaker outputs. If desired, a discrete stereo amplifier could be used to drive the front speakers in place of the audio system in the TV set.
Since the left (34) and right (35) surround outputs from the decoder (3) are the same, except 180°out of phase, it is not necessary to separately amplify the two. Optionally, only one (35) may be used as an input to one channel (21) of the stereo amplifier (4). The corresponding output (26) of the amplifier feeds the right (10) surround speaker directly, and the left (9) surround speaker is connected in parallel, but with the wires reversed. The reversed wires result in an audio signal which is 180°out of phase, or the same as that produced by the other surround output from the decoder. This connection allows the other channel of the stereo amplifier (23) to be used to amplify the center channel output (36) of the decoder (3) and drive center speaker (8).
If the user desires, the two surround speakers could be replaced by a single bipolar (bi-directional) speaker centered behind the listener.
A sub-woofer amplifier and speaker (not shown) could be connected to the sub-bass output (37) of the decoder. Since sub-bass sound is not directional, the subwoofer could be placed anywhere convenient in the room.
The decoder circuit of the invention can be used, in reverse, to record stereo audio with surround information. FIGS. 3 and 4 show the circuit in use in such an application. The recorder (5) could be an audio recorder, or a video camera/recorder with stereo audio.
In the configuration shown in FIG. 3, three microphones--center (54), left surround (53) and right surround (56)--are used to record the sound. The configuration of FIG. 4 is otherwise identical, but uses one bipolar microphone (63) (such as a ribbon microphone) to record the surround information.
The center microphone can be the conventional microphone on the camcorder, or could be a remote microphone centered on the subject (i.e. actor or stage) and transmitting back to the camcorder by an IR or RF link. In any event, the center microphone is used to record the subject, dialog, etc.
The surround microphone(s) record the ambiance/surround information. They would preferably be placed on the camcorder or behind it, pointed outwards.
The left and right record inputs (51) on the recorder (50) are connected to the end connections of the primary winding (60) of the transformer (58). The center microphone (54) signal is connected to the center tap (52) of the primary winding, possibly through a balance control (55). As before, the center tap of the secondary winding (62) is grounded.
If there are two surround microphones (FIG. 3) (53) and (56), they are connected to the end connections (57) and (61) of the secondary winding of the transformer (58). If one bipolar microphone (FIG. 4) (63) is used, it is connected to one of the end connections (57) of the secondary winding of the transformer, and the other is left unused.
FIG. 5 shows how the circuit may be used in pairs, back to back, to modify existing stereo recordings to incorporate a simulation of surround sound (sometimes called "magic surround").
The source input (70) is fed into the end connections of the primary winding (76) of first transformer (71). The outputs from this transformer are the L+R sum signal from the center tap (83) of the primary winding of the first transformer (71) and the L-R difference signal from one end connection (75) of the secondary winding. The center tap of the secondary (81) is once again grounded, and the other end connection (79) of the secondary is unused.
The sum and difference signals are fed into the two channels of a stereo mixer (74a) (74b). The sum signal is simply amplified by one channel of the mixer and passed on to the center tap (84) of the primary winding of the second transformer (72). The end connections of the primary winding (78) of the second transformer (72) become the input (71) to a recorder.
The difference signal (L-R) passes through the other channel of the stereo mixer (74) and to one of the end connections (77) of the secondary winding of the second transformer (72). The other end connection (80) is unused, and the center tap (82) of the secondary is grounded.
This arrangement can create surround effects through the use of a reverberator (73) in the difference signal channel of the stereo mixer (74a). By separating sum and difference signals in the first transformer (71), adding reverb or other effects to the difference channel in the mixer (74), then recombining the signals in the second transformer (72), left and right output signals (71) with a simulation of surround sound can be created. The input to the reverb may be taken from the center channel mixer (74b) which will provide a realistic surround effect.
Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments are not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention. | A passive circuit for decoding surround-sound signals using a transformer having center-tapped primary and secondary windings. The line level left and right signals are introduced into the primary winding, and the center tap of the primary supplies a left-plus-right center channel output. The secondary center tap is grounded, and the winding connections supply left-minus-right and right-minus-left surround outputs. The same circuit can be used for recording surround sound onto a two-channel (stereo) medium. A center microphone is connected to the center tap of the primary winding. Left and right surround microphones are connected to the secondary winding, which has its center tap grounded. The left and right recorder inputs are connected to the opposite sides of the primary winding. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to a combination tool for use in oil well drilling and production. The tool performs both cutting and retrieving functions within a well bore.
Prior tubing cutters of various types are known, including exposive devices and tools having cutter knives operated by hydraulic pistons to which fluid pressure is directed from the surface. Hydraulic cutters tend to be complex, and therefore expensive and difficult to operate, and explosive devices have well-known shortcomings and dangers Furthermore, none of the prior devices is capable of both cutting a fish and retrieving it from the well in a single operation.
Purely mechanical tubing cutters are also well known. These, as a rule, require that the tubing supporting the tool be rotated at the surface when it is desired to perform a cut. A problem associated with tools actuated by rotary motion occurs when well bores are highly deviated, that is, not straight. Such bores may deviate from the vertical by over 60° . In such cases, wall friction between the casing and the tubing makes rotary motion very difficult to impart and control from the surface.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide a mechanical tubing cutter capable of grasping heavy fish with sufficient force to lift the fish out of the well, and to provide a purely mechanical tool which executes clamping, cutting and retrieving steps in automatic sequence.
Another object is to provide such a tool which is actuated by a linear lifting force, rather than by rotation, and which performs the clamping, cutting and retrieving steps at predictable force levels.
A further object is to provide a tubing cutter which can be easily be converted to a releasing overshot.
The present invention is embodied in a tubing cutter comprising a hollow cylindrical housing containing: a cutter assembly having plural knives with inclined upper cam surfaces, a slip body above the cutter, the body comprising plural cam-operated slips for clamping the tubing by applying radial force thereto, and having a lower conical surface for engaging the upper cam surfaces of the knives, a slip actuator above the slip body, the acutator having a lower conical surface for actuating the slips, and means, above the slip actuator, for engaging a projection on the tubing. The engaging means, the actuator and the slip body are all retained in installed axial positions within the housing by first, second and third shear pins, respectively, the pins having different strengths so as to fail progressively, the first pin being the weakest of the three and the third pin being the strongest. When the device is placed over the tubing and then pulled upward toward the projection with progressive force, the tubing is first engaged by the engaging means, then clamped by actuation of the slips, and then cut by actuation of the cutter.
BRIEF DESCRIPTION OF THE DRAWINGS
A tool embodying the is shown in the accompanying drawings, wherein FIG. 1 is a cross-sectional view of a tubing cutter embodying the invention, taken along a plane containing the longitudinal axis of the tool;
FIG. 2 shows an alternative form of the tool, useable releasing overshot;
FIG. 3 shows the dog assembly of the invention in exploded isometric;
FIG. 4 is an isometric view illustrating operation of the dog assembly;
FIG. 5 shows the tool in clamping engagement with a fish, prior to cutting;
FIG. 6 shows the severed fish being removed from a well bore, and
FIG. 7 shows a variation of the dog assembly, corresponding to FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A tubing cutter embodying the invention includes a cylindrical hollow housing 10 having an open upper end internally threaded at 12 for attachment at the bottom of a wash pipe (not shown). The housing has an integral, annular bottom or "driving ring" 14 with a bore 16 sufficiently large to pass over drill string collars and the like. The housing contains four major components, capable of linear movement with respect to one another within the housing. From top to bottom, these components are: a dog assembly 20 for engaging tubing shoulders or collars in a cutting or fishing operation; a slip body actuator 60; a collet-type slip body 70; and a collet-type cutter 80. The cutter rests normally on the bottom 14 of the housing 10. The cutter, slip body, and actuator each have a pairs of lugs L which extend through corresponding vertical slots S in the housing wall to delimit the vertical motion of each.
Of the assemblies contained within the housing, the dog assembly 20 is uppermost. This assembly, shown in detail in FIGS. 3 and 4, comprises a cage 22 having four equally spaced slots 24 extending radially from the inside diameter 26 to the outside diameter 28 of the cage. A dog 30 is retained within each of the slots, for pivoting movement about a pin 32 which extends through the dog and into the sides 34 of the cage slot. Each dog has a flattened "V" shape and is pinned at the intersection of the legs of the "V".
The cage 22 rests on an antifriction thrust bearing 36 within a cup-shaped dog cam ring 38 having a peripheral annular wall 40. Four equally spaced cam surfaces 42, one facing each of the dogs, are formed on the inner wall surface 44. The lower wing 46 of each dog has a rounded end 48 generally conforming to the shape of the cam surfaces. Clockwise rotation of the ring relative to the cage causes the cam surfaces to push the lower ends of the dogs radially inward, forcing each dog to a more vertical orientation to release a tubing shoulder engaged by the dogs. The necessary rotation is transmitted to the ring from the drill string by a coil spring 58, described below.
The annular wall 40 of the release ring has a radially extending blind hole 50 in its inner surface 44, disposed between an adjacent pair of the cam surfaces 42. The cage 22 has a corresponding hole 52 in its outer surface 54, so positioned that the two holes 50,52 are aligned only when the dogs are in their fully released position. The dog cam ring and cage are assembled with these holes misaligned, in relative positions corresponding to the locking position of the dogs, and a hardened pin 54 is installed in the blind hole in the release ring, with a spring 56 behind it. When the dog cam ring is turned to the release position, as explained below, the pin 54 latches into the hole 52 in the cage, so as to lock the ring and cage in the open position and to thereby prevent further relative rotation.
A right-hand helix coil compression spring 58 (FIG. 1), having an outer diameter about equal to the inner diameter of the housing 10, is positioned below and in contact with the bottom surface of the dog cam ring; the end of the spring is preferably seated in a groove in the ring to prevent relative rotation of the parts. The lower end of the spring is supported on the upper surface of the next lower component, the floating slip body actuator 60, and is correspondingly seated at that point.
The actuator 60 has a flat upper surface 62, an outer diameter 64 that is a sliding fit in the housing, an inner diameter 66 sufficiently large to pass over any fish, and an upwardly converging frustoconical bottom surface 68. The lugs L extending outwardly from the outer diameter of the floating slip body cone into the vertical slots S in the housing to prevent relative rotation.
The slip body 70 is a unitary body comprising a sleeve with a frustoconical upper surface 72 having the same apex angle as the bottom surface 68 of the actuator. A plurality of radially extending slots 74 opening inwardly to the bore of the slip body define plural resilient slip body fingers 76, which are provided with serrated inner surfaces 78 for engaging the wall of a tube. The fingers are internally undercut to make them sufficiently resilient. The bottom surface 79 of the slip body defines the frustum of an upwardly converging cone.
The cutter body 80, like the slip body, is unitary, and has an upper frustoconical surface 82 with an apex angle like that of the bottom surface 79 of the slip body. The upper portion of the body is divided by radial slots 84 into a plurality of knives 86 having inwardly directed chisel edges 88 at their upper ends. The knives are exteriorly undercut so as to have adequate resilience.
The dog assembly, actuator, and cutter are retained in their installed positions, with gaps therebetween, by shear pins 90, 92 and 94 designed to fail at different, predetermined axial force levels. The dog assembly retaining pin 90, for example, is rated at 2500 lbs.; the actuator pin 92 is designed to fail at 10,000 lbs.; and the slip body pin 94 fails at 20,000 lbs. shear. The shear pins provide sequential, predictable clamping and cutting events, and insure that the upper portion of that which is cut remains retained by the tool for immediate removal from the well.
In operation, the tool is run down the well and over the end of the fish. Once the tool is at the desired point on the fish, it is retracted until the dogs engage a shoulder or collar on the fish, as shown in FIG. 5. The upward force on the tool maintains the dogs in firm engagement beneath the shoulder thereafter. The lifting force is then progressively increased. As the shear pin 90 fails, the dog assembly moves toward the actuator, compressing the spring 58. At a lifting force of 10,000 pounds, the shear pin 92 fails, allowing the spring to drive the actuator downward against the slip body, closing the slip body fingers around the tubing. This position is illustrated in FIG. 5. Subsequently, when the lifting force reaches 20,000 pounds, the shear pin 94 is broken, and the slip body is driven downward against the cutter 80, forcing the cutter knives inward against the tubing. The tool may be jarred up and down to complete the cut if necessary. Once the fish is cut, its upper portion, still in the grip of the slip body fingers, may be lifted safely from the well, as shown in FIG 6.
When desired, the cutter knives and slip body may be retracted by bumping the tool downward, sufficiently that the tops of the slots S strike the lugs L. The heights of the slots are selected so that the parts are deactivated in the reverse order of the sequence in which they were activated.
The tool described above may be converted to a releasing overshot merely by replacing the cutter with a simple sleeve 180, as shown in FIG. 2. Now, when the tool is run over a fish, the dogs engage beneath a shoulder of the fish to engage it a provide the resistance to lifting necessary to actuate the tool. Once sufficient force is applied to break the first and second shear pins, the actuator drives the slip body fingers against the exterior of the fish, to clamp it. As the third pin breaks, no cutting occurs, but the upward force created on the clip by the sleeve increases the compression of the slip body fingers, thus enabling extremely heavy fish to be lifted. If, however, the fish is stuck and cannot be removed, the releasing dog feature of the invention permits the supervisor to disengage the dogs from the fish shoulder (by rotating the drill string, and thus, the dog assembly dog cam ring 38) and remove the tool, without damaging it. In the past, it has been necessary to break off the dogs in order to disengage the overshot from the fish.
FIG. 7 shows a variation of the dog assembly wherein the cam surfaces of the dog cam ring 140 are replaced by stepped recesses designated generally as 142, each comprising a shallow recess 142A adjacent a deeper recess 142B. In this embodiment also, the dogs 130 have a radially inner wing 145 and an outer wing 146 with a negative dihedral angle therebetween, so that the dogs pivot downward to release the fish, rather than upward. Otherwise, the assemblies are identical, as shown by identical reference numerals, and operation of the assembly is very similar to that described above. It can be seen that clockwise rotation of the ring 140 permits the dog wing 145 to fall downward, to release the fish.
Inasmuch as the invention is subject to variations, it is intended that the foregoing description and the accompanying drawings shall be interpreted merely as illustrative of the invention, which is to be measured by the following claims. | A mechanical tubing cutter for severing and retrieving fish from wells comprises a slip body for clamping the upper end of the fish, and cam-actuated cutter knives for severing the fish below the slip body. The clamping and cutting operations occur in an automatic and predictable sequence as upward force is progressively applied to the tool. The tool may be used as a releasing overshot merely by substituting a slip body setting sleeve for the cutter knives. | 4 |
RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. § 119(e) of prior U.S. Provisional Patent Application No. 61/503,843, filed Jul. 1, 2011, which is incorporated herein by reference.
TECHNICAL FIELD
[0002] Various embodiments described herein relate to a system and a method for forming a pressure sensor (hydrophone), which can be used as part of an array that includes a number of pressure sensors. The sensors and the array are used for receiving acoustic sound in the water. In one embodiment, the sensors are used on vessels, such as a submarine, as part of a Sonar system.
BACKGROUND
[0003] Sonar is a well known apparatus having both civilian and military applications. Sonar (originally an acronym for SOund Navigation And Ranging) is a technique that uses sound propagation, usually underwater, to navigate, communicate with or detect other vessels. Sonar uses sensors placed in arrays to receive sound. The arrays can be deployed in many ways. Some sonar arrays are towed behind a ship or submarine. Towing an array of sensors or hydrophones presents many problems. Another way to deploy an array is by mounting sensors to the hull of a ship, such as a submarine. Hull mounted sonar arrays are generally built up from separate components at several hull mount sites on a hull. Typically, there are a number of hull mount sites that are aligned along the starboard side of the hull and an equal number of hull mount sites aligned along the port side of the hull In many instances, the individual sensors are made from solid ceramic plates or solid ceramic blocks and so are also heavy. Heavy sensors results in a heavy array of sensors. The heavy arrays add to the weight of the assembly needed for a hull mounted array.
[0004] Sensor hydrophone converts acoustic signal into an electrical signal using a piezoelectric material. The piezoelectric material is bound by first plate and a second plate. Acoustic pressure waves impinge on the first plate and the second plate or top and bottom surfaces of the sensor, respectively. The variation in pressure squeezes or strains the active piezoelectric material to generate a voltage which is substantially proportional to a voltage produced by the piezoelectric material, such as ceramic. The chemical properties of the piezoelectric material generate the voltage. The voltage potential resulting from the acoustic sound waves is measured an input to signal processing systems to produce useful information in locating other ships and other structures. Sonar can be used to locate ships above or below the surface and can also be used to determine characteristics of the ocean floor. For example, one use of the sensors or hydrophones can be for undersea exploration for oil or other natural resources.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a side view of a vessel including an array of sonar sensors, according to an example embodiment.
[0006] FIG. 2 is a perspective of a portion of the array in which a baffle, SCP, and VIM are one molded piece, according to an example embodiment.
[0007] FIG. 3 is a schematic cross sectional view of an individual acoustic pressure sensor, according to an example embodiment.
[0008] FIG. 4 is a side section view of an acoustic pressure sensor, according to an example embodiment.
[0009] FIG. 5 is a top view of an acoustic pressure sensor, according to an example embodiment.
[0010] FIG. 6 is a blown up perspective view of an acoustic pressure sensor, according to an example embodiment.
[0011] FIG. 7 is a perspective view of a finished acoustic pressure sensor, according to an example embodiment.
[0012] FIG. 8 is a blown up perspective view of another embodiment of an acoustic pressure sensor, according to an example embodiment.
[0013] FIG. 9 is a perspective view of a square acoustic pressure sensor partially assembled, according to an example embodiment.
[0014] FIG. 10 is a perspective view of a square acoustic pressure sensor as assembled, according to an example embodiment.
[0015] FIG. 11 is a perspective view of a round acoustic pressure sensor as assembled, according to an example embodiment.
[0016] FIG. 12 is a blown up perspective view of a round acoustic pressure sensor, according to an example embodiment.
[0017] FIG. 13 is a perspective view of the round acoustic pressure sensor encased in a viscioelastic material, according to an example embodiment.
[0018] FIG. 14 is a perspective view of a partially assembled round acoustic pressure sensor, according to an example embodiment.
[0019] FIG. 15 is a perspective view of a fully assembled round acoustic pressure sensor, according to an example embodiment.
[0020] FIG. 16 is one possible cross-section view along line A-A in FIG. 15 , according to an example embodiment.
[0021] FIG. 17 is one possible cross-section view along line A-A in FIG. 15 , according to an example embodiment.
DETAILED DESCRIPTION
[0022] FIG. 1 is a side view of a vessel 100 including an array of sonar sensors 120 , according to an example embodiment. The vessel 100 is a submarine. It should be understood that other types of vessels may also include an array of sonar sensors. The array of sonar sensors 120 includes a number of subarrays of sonar sensors that are added to other components to form a panel, such as panels 122 , 124 , 126 . The vessel's 100 port side is shown with three panels 122 , 124 , 126 that include sonar sensors. The panels 122 , 124 , 126 are positioned along the port side of the vessel 100 . The starboard side of the vessel 100 also includes three similarly positioned panels (not shown) of sonar sensors. In total, there are six panels on the vessel that form the array 120 . It should be noted that other arrays can have a different number of panels. Some vessels 100 may include more panels and some vessels may include fewer panels to form an array of sensors.
[0023] FIG. 2 is a perspective of a portion of one of the panels, such as panel 122 , of the array of sonar sensors 120 , according to an example embodiment. The sensors may be laid out in a hexagonal pattern to increase packing density which increases performance.
[0024] FIG. 3 is a schematic cross sectional view of an individual acoustic pressure sensor 600 , according to an example embodiment. The sensor 600 includes a first plate 610 and a second plate 612 . Sandwiched between the first plate 610 and the second plate 612 are columns of ceramic material, such as columns 632 , 634 , 636 . The columns can be of any shape. For example, the cross section may be circular or square or rectangular in shape and these are low cost readily available parts. The columns of ceramic material are a piezoelectric material that produces electricity in response to pressure or force placed on the material. An electrical charge accumulates in certain solid materials (such as the ceramic used for the columns 632 , 634 , 636 in the pressure sensor 600 ) in response to applied mechanical strain. Sound waves, whether in water, air, or otherwise, are pressure waves. When the sound wave or pressure wave strikes a first plate 610 the force is transferred to the columns 632 , 634 , 636 of piezoelectric material.
[0025] In fact, the columns 632 , 634 , 636 act as pressure concentrators. Pressure is force per unit area. When the force passes through the columns 632 , 634 , 636 , the force is distributed over a smaller area and therefore pressure at the columns 632 , 634 , 636 is higher than the pressure on the first plate 610 . The columns 632 , 634 , 636 of piezoelectric material generate electricity when subjected to a pressure change. Electrical connections are made to the columns which produce signals in response to the variations of pressure caused by sound waves.
[0026] In other embodiments, the ceramic or piezoelectric material need not be formed in columns. The first plate 610 and the second plate 612 have major surfaces with an area. The ceramic or piezoelectric material interacts with less than the full surface area of these major surfaces. The ceramic or piezoelectric material could be shaped as cubes or even shorter flat rectangles.
[0027] The surface area of the ceramic or piezoelectric material interfacing with the major surface of one of the first plate 610 and the second plate 612 will be less than the surface area of the major surface. The piezoelectric material or ceramic material is heavy. In such an arrangement, less ceramic material is used and the resultant sensor formed is lighter than previous sensors. Previous sensors included a substantially solid plate of ceramic between a first plate and a second plate. Using portions of ceramic or piezoelectric material rather than a solid plate of ceramic between the first plate 610 and the second plate 612 lightens the sensor. The ratios between the surface area of the first plate 610 or the second plate 612 (caps) and the piezoelectric material portions is in a range of between 3:1 to 11:1. It has been found that surface area ratios within the above range provide at least as good if not superior performance in a sensor that is less costly to build and which has less weight.
[0028] FIG. 4 is a side section view of an acoustic pressure sensor 700 , according to an example embodiment. The pressure sensor 700 includes a first plate 710 and a second plate 720 . Sandwiched between the first plate 710 and the second plate 720 are columns of piezoelectric material, three of which can be seen, 732 , 734 , 736 . FIG. 5 is a top view of an acoustic pressure sensor 700 with the second plate 720 removed, according to an example embodiment. This shows that the piezoelectric columns, such as 732 , 734 , 736 are actually ring-shaped. The ring-shaped piezoelectric material portions have openings therein, 731 , 733 , 735 , respectively. The openings 731 , 733 , 735 in the middle of the piezoelectric portions 732 , 734 , 736 can receive a fastener, such a screw or bolt. The fasteners (not shown) pass through the openings 731 , 733 , 735 and attach the first plate 710 to the second plate 720 .
[0029] FIG. 6 is a blown up perspective view of an acoustic pressure sensor 700 , according to an example embodiment. In this example embodiment, there are twelve piezoelectric portions, such as 732 , 734 , 736 that are ring-shaped. Each ring-shaped piezoelectric material portion 732 , 734 , 736 has an opening therein, such as openings 731 , 733 , 735 , respectively. The first plate 710 and the second plate 720 also include twelve openings. As shown plate 710 includes openings 711 , 713 , 715 amongst the twelve openings, and plate 720 includes openings 721 , 723 , 725 amongst the twelve openings on that plate 720 . The openings in the first plate 710 and the openings in the second plate 720 substantially align. In some embodiments of the pressure sensor 700 , a spacer can be provided. The spacer also includes twelve openings, such as openings 741 , 743 , and 745 . The openings 741 , 743 , and 745 are sized to receive the ring-shaped piezoelectric material portions, such as 732 , 734 , 736 and hold them in proper alignment so that a fastener can pass through opening 725 in plate 720 , opening 735 in ceramic piece 736 , and opening 715 in plate 710 . The sensor 700 includes an acoustic isolation wall around perimeter of the sensor plates 710 , 720 . The wall can be a single part or a an assembly that includes several parts. As shown in FIG. 6 , the wall 750 includes a first wall component 751 and a second wall component 752 that form the acoustic wall 750 . This wall must be sufficiently stiff to resist movement from the acoustic waves but decoupled from the first plate 710 and the second plate 720 (caps) with a flexible layer to prevent the two caps from being bonded together. In one embodiment, the wall can be molded directly into the cap to reduce part count. A shorter wall could be molded into both the first plate 710 and second plate 720 (caps). In this embodiment, when the two plates are caps are assembled a wall will formed. A flexible layer will be required in each of these configurations to prevent the two caps or plates from effectively bonding together.
[0030] Fasteners, such as screws or bolts placed through the ceramic centers and the plates 710 , 720 support alignment, coupling, and “bond” strength of the assembled sensor 700 . Once assembled, the sensor is placed in a mold and urethane plastic or some other waterproof material having the same or similar properties as water (seawater or fresh water) is pumped into the chamber, pressurized and held at temperature for an amount of time. The urethane or other material must not fill the interstitial spaces your between the components making up the sensor 700 to leave an essential air gap allowing for coupling of the incident acoustic wave with the piezoelectric material. In one example embodiment a flexible material spacer could fill the space between the piezoelectric pieces to prevent a material such as urethane or water from filling the space. In one example embodiment, a layer of electrically isolative material is inserted between the ceramic and one of the first plate 710 or the second plate 720 . In this example embodiment, the plate/wall housing can be used to achieve full electrical shielding for the sensor 700 . Of course, it is contemplated that in alternative embodiments, the shape and size of these sensors as well as the quantity of ceramics in each sensor assembly could be varied. The sensors discussed above deliver increased sensitivity above baseline through a unique low cost geometry of piezoelectric material to plate coupling.
[0031] FIG. 7 is a perspective view of a finished acoustic pressure sensor 700 , according to an example embodiment. The sensor 700 is encased in urethane material 1000 . The resulting sensor 700 has a low-profile; and works in current reflecting plate scenarios. The example embodiment has no tabs to break so it is more rugged than some current designs. In addition, the sensor 700 is lightweight when compared to sensors having a solid ceramic plate and has a weight of approximately 7.5 g/cm 2 . In addition, noise figure of merit is 10 dB higher than sensors that have a lead titanate design. In another embodiment, the ceramic thickness of the piezoelectric portions is doubled, and the noise figure of merit increases 40%. The sensor 700 also substantially maximizes flow noise area averaging.
[0032] The sensors 600 , 700 or hydrophones are designed to work in frequency ranges where the wavelength is greater than the size of the transducer. This region results in a mostly omnidirectional transducer where the entire sensor is engulfed in each pressure wave. It should be noted, that other sensors that are less than ⅛ of the wavelength in thickness can benefit from reflection gain from a signal conditioning plate when in an array. The polarization direction in the embodiment of sensors 600 , 700 is axial. In other words, the hydrophone or sensor 600 , 700 ceramic is active in the 3-3 mode. When active in the 3-3 mode, the voltage is measured from electrodes in the same direction as the ceramic is polarized. The above described structure will work on other types of sensors. For example, the same geometry could also be expanded to use materials in the 3-1 mode where the polarization direction is orthogonal to the voltage electrode direction for materials that make this mode desirable.
[0033] FIG. 8 is a blown up perspective view of another embodiment of an acoustic pressure sensor 800 , according to an example embodiment. The pressure sensor 800 and includes a first plate 810 and a second plate 820 . The pressure sensor 800 is substantially square in shape and includes 16 piezoelectric portions, such as 831 , 833 , 835 . Each of the PAs electric portions 831 , 833 , 835 includes an opening therein which is sized to receive a fastener, such as fasteners 841 , 843 , 845 . The first plate 810 also includes openings which correspond to the fasteners 841 , 843 , 845 . Similarly the second plate also includes openings which correspond to the fasteners 841 , 843 , 845 . Also included in the pressure sensor 800 is a wall 850 . The wall 850 is a unitary unit which provides acoustic isolation at the perimeter of the sensor plates 810 , 820 . The wall 850 can be thought of as a frame sized to substantially match the perimeter of the sensor plates 810 , 820 . The frame or wall 850 is sufficiently stiff to resist movement from the acoustic waves while being decoupled from the first plate 810 and the second plate 820 . The decoupling prevents the wall from joining or bonding the first plate 810 and the second plate 820 and maintains the acoustic isolation of the elements within the frame or wall 850 .
[0034] FIG. 9 is a perspective view of a square acoustic pressure sensor partially assembled, according to an example embodiment. As shown, the fasteners 841 , 843 , 845 have passed through the first plate 810 and through the openings in the ring shaped piezoelectric portions 831 , 833 , 835 . To complete the assembly, the frame or wall 850 has to be placed about the perimeter of the first and second plates 810 , 820 . As a practical matter, the frame 850 will be placed onto the outer perimeter of the first plate 810 as shown in FIG. 9 . The second plate 820 will then be placed onto the fasteners, such as fasteners 841 , 843 , 845 to complete the assembly. It should be noted that is shown in FIG. 9 , acoustically isolated material is placed between the piezoelectric portions during assembly so that it is captured between the first plate 810 the second plate 820 and the wall 850 . FIG. 10 is a perspective view of a square acoustic pressure sensor as assembled, according to an example embodiment. In other words FIG. 10 is a perspective view of the square acoustic pressure sensor 800 after the partial assembly of FIG. 9 is completed. It should be noted that the first plate 810 second plate 820 are made of aluminum. In other embodiments of the invention the first plate and second plate are made of steel. The assembly shown in FIG. 10 generally encased in urethane or a similar material so the sensor is sufficiently ruggedized to work in various environments, such as in an ocean or other environment.
[0035] FIG. 11 is a perspective view of a round acoustic pressure sensor 1100 as assembled, according to an example embodiment. FIG. 12 is a blown up perspective view of a round acoustic pressure sensor 1100 , according to an example embodiment. Now referring to both FIGS. 11 and 12 , the round acoustic pressure sensor 1100 will be further detailed. As shown, the round sensor 1100 includes a first round plate 1110 and a second round plate 1120 and a wall 1150 . The wall 1150 is annular. The wall has an outside perimeter which is substantially the same as the outside perimeter of the first plate 1110 and the second plate 1120 . The sensor 1100 also includes a piezoelectric ring 1130 . The round sensor 1100 can also include a center support structure 1140 to stiffen the caps (first plate 1110 and second plate 1120 ). If the caps (first plate 1110 and second plate 1120 ) are too flexible, they will not effectively transfer the acoustic pressure into the piezoelectricity. The support structure 1140 is generally not made of a piezoelectric material and is made of a material that will support the first plate 1110 and the second plate 1120 . As shown in FIG. 12 , the support structure 1140 is centered with respect to the first plate 1110 and the second plate 1120 . The support structure 1140 also is tubular in shape and has an opening which can receive a fastener 1141 . The fastener 1141 passes through the first plate 1110 the support structure 1140 and the second plate 1120 . As mentioned above, the support structure provide stiffness to the first plate 1110 and the second plate 1120 which is spanning the space between the wall 1150 and the piezoelectric element 1130 . The area ratio between the center support 1140 and the piezo-electric material 1130 should be at least 1:10 so that the center support 1140 does not interfere with transferring load through the piezo-electric material 1130 . In one embodiment the center support structure 1140 is a separate element. In another embodiment, the center support may be molded directly into the caps (the first plate 1110 and the second plate 1120 ) to reduce part count. Also included in the sensor 1100 is a flexible layer 1160 which prevents the wall 1150 from coupling or bonding together the first plate 1110 and the second plate 1120 .
[0036] FIG. 13 is a perspective view of the round acoustic pressure sensor 1100 encased in a urethane material, according to an example embodiment. The urethane material ruggedized as the archer sensor 1100 so they can be used in various environments. The urethane material generally will not affect the ability of the sensor 1100 to detect pressure waves. The final assembly also includes electrically coupling the PAs electric element 1130 (shown in FIG. 12 ). As shown in FIG. 13 , wires attached to the ring provide the electrical coupling.
[0037] FIG. 14 is a perspective view of a partially assembled round acoustic pressure sensor 1400 , according to an example embodiment. The acoustic pressure sensor 1400 is very similar to the acoustic pressure sensor 1100 . Rather than describe the pressure sensor 1400 in detail, for the sake of clarity and brevity, only the differences between the pressure sensor 1100 and the pressure sensor 1400 will be discussed. As shown in FIG. 14 the piezoelectric element 1130 is encased in acoustically isolated material. In the pressure sensor 1100 , acoustically isolated material can also be placed about the piezoelectric element 1130 . Among the differences is that the ring 1160 of the coupling material between the first plate 1110 and the second plate 1120 is placed directly onto the second plate 1120 . This reduces the part count and eases assembly of the sensor 1400 .
[0038] FIG. 15 is a perspective view of a fully assembled round acoustic pressure sensor 1500 , according to an example embodiment. Sensors 1500 could be assembled in a number of different ways. The basic idea of sensor 1500 is that the wall 1150 of the previous sensors 1100 , 1400 can be incorporated into the first plate and the second plate. Now referring to both FIGS. 16 and 17 , two possible cross-sectional areas of the first plate and the second plate will now be shown.
[0039] FIG. 16 is one possible cross-section view along line A-A in FIG. 15 , according to an example embodiment. The first plate 1610 includes a wall 1660 and a support structure 1640 . The wall 1660 , in one embodiment, is a half wall. In other words the second plate will be similarly shaped in dimensioned so that when the first plate 1610 and the second plate are connected they form the wall 1660 . Similarly the support structure 1640 is also a half wall or half support so that the first plate 1610 and second plate are similarly shaped. It should be understood that the wall 1660 of the first plate 1610 could also be a full wall and that the support structure 1640 can also be a full support structure. In this case, a flat second plate would be connected to the first plate 1610 to form the round sensor 1500 .
[0040] FIG. 17 is one possible cross-section view along line A-A in FIG. 15 , according to an example embodiment. In this particular embodiment, the first plate 1710 is provided with a wall 1760 . Unlike the first plate 1610 , the first plate 1710 does not include a support structure. The wall 1760 could be a half wall or a full wall. A separate support structure, such as support structure 1140 (shown in FIG. 12 ) could be used. Of course, during assembly the first plate and second plate must be separated by a dampening material so as not to bond or unify the first plate and the second plate.
[0041] This has been a detailed description of some exemplary embodiments of the invention(s) contained within the disclosed subject matter. Such invention(s) may be referred to, individually and/or collectively, herein by the term “invention” merely for convenience and without intending to limit the scope of this application to any single invention or inventive concept if more than one is in fact disclosed. The detailed description refers to the accompanying drawings that form a part hereof and which shows by way of illustration, but not of limitation, some specific embodiments of the invention, including a preferred embodiment. These embodiments are described in sufficient detail to enable those of ordinary skill in the art to understand and implement the inventive subject matter. Other embodiments may be utilized and changes may be made without departing from the scope of the inventive subject matter. Thus, although specific embodiments have been illustrated and described herein, any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description. | A sensor includes a first plate, a second plate, and a piezoelectric material portions. The piezoelectric material portions are positioned between the first plate and the second plate. The area of the piezoelectric material portions is less than the area of the plates. The plates can be supported with a center support structure. The width of the sensor is significantly greater than its height. The interstitial space is filled with a flexible material. An outside wall isolates the inside from the outside | 8 |
RELATED APPLICATIONS
The present application claims priority to U.S. Provisional Application 62/085,007, filed Nov. 26, 2014, the entire contents of which are incorporated herein by reference.
BACKGROUND
The present invention relates to electronic door lock systems and methods.
SUMMARY
Some embodiments of the present invention provide an electronic door lock system comprising a latch having a latched position and an unlatched position; an interior unit including an interior handle operable to place the latch in the unlatched position, an interior user-interface, and an interior controller communicatively coupled to the interior user-interface; an exterior unit including an exterior handle having an active mode and a non-active mode, the exterior handle operable to place the latch in the unlatched position when in the active mode, an exterior user-interface, a fingerprint sensor configured to sense fingerprint data, and an exterior controller configure to receive the sensed fingerprint data, output the sensed fingerprint data, and place the exterior handle in the active mode upon receiving an active signal; and a main controller communicatively coupled to the interior controller and the exterior controller, the main controller configured to receive the sensed fingerprint data from the exterior controller, compare the sensed fingerprint data to a known fingerprint data, and output the active signal to the exterior controller based on the comparison.
In some embodiments, an electronic door lock system is provided, and comprises a latch having a latched position and an unlatched position; an interior unit including an interior handle operable to place the latch in the unlatched position, and an interior user-interface having an interior display; an exterior unit including an exterior handle having an active mode and a non-active mode, the exterior handle operable to place the latch in the unlatched position when in the active mode, an exterior user-interface having an exterior display, a fingerprint sensor configured to sense fingerprint data and output the sensed fingerprint data; and a main controller communicatively coupled to the interior unit and the exterior unit, the main controller configured to receive the sensed fingerprint data, compare the sensed fingerprint data to a known fingerprint data, and place the exterior handle in the active mode based on the comparison.
Some embodiments of the present invention provide an electronic door lock system comprising a latch having a latched position and an unlatched position; an interior unit including an interior handle operable to place the latch in the unlatched position, and an interior user-interface having an interior display; an exterior unit including an exterior handle having an active mode and a non-active mode, the exterior handle operable to place the latch in the unlatched position when in the active mode, an exterior user-interface having an exterior display, a fingerprint sensor configured to sense fingerprint data and output the sensed fingerprint data; a wireless power supply module; a wireless network communications module; and a main controller communicatively coupled to the interior unit, the exterior unit, the wireless power supply module, and the wireless network communications module, the main controller configured to receive the sensed fingerprint data, compare the sensed fingerprint data to a known fingerprint data, and place the exterior handle in the active mode based on the comparison.
In some embodiments, an electronic lock network is provided, and comprises a plurality of lock systems each including a latch having a latched position and an unlatched position, an interior unit including an interior handle operable to place the latch in the unlatched position, an exterior unit including an exterior handle having an active mode and a non-active mode, the exterior handle operable to place the latch in the unlatched position when in the active mode, and a fingerprint sensor configured to sense fingerprint data and output the sensed fingerprint data, a wireless power supply, a wireless network communications module, and a controller communicatively coupled to the wireless power supply and the wireless network communication module, the main controller configured to receive the sensed fingerprint data, compare the sensed fingerprint data to a known fingerprint data, and place the exterior handle in the active mode based on the comparison; and an external computer including a second wireless network communications module, the external computer configured to send the known fingerprint data to at least one of the plurality of lock systems over a wireless mesh network comprising the plurality of lock systems.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of an interior portion of a lock system according to one embodiment of the invention.
FIG. 2 is a perspective view of an exterior portion of the lock system of FIG. 1 .
FIG. 3 is a front view of the interior portion of FIG. 1 .
FIG. 4 is a front view of the exterior portion of FIG. 2 .
FIG. 5 is a bottom view of the interior portion of FIG. 1 illustrating an input/output according to one embodiment of the invention.
FIG. 6 is a block diagram of a control system of the lock system of FIG. 1 .
FIG. 7 is a front view of the exterior portion of FIG. 2 illustrating a fingerprint sensor according to one embodiment of the invention.
FIG. 8 is a flowchart illustrating an operation of the lock system of FIG. 1 .
FIG. 9 is a flowchart illustrating another operation of the lock system of FIG. 1 .
FIG. 10 is a flowchart illustrating another operation of the lock system of FIG. 1 .
FIG. 11 is a flowchart illustrating another operation of the lock system of FIG. 1 .
FIG. 12 one embodiment of a mesh network of a plurality of lock systems of FIG. 1 .
FIG. 13 illustrates a process, or communication protocol, for determining a communication path between nodes of the mesh network of FIG. 12 .
FIG. 14 illustrates a software decision tree the lock system of FIG. 1 .
DETAILED DESCRIPTION
Before embodiments of the present invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the accompanying drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
FIGS. 1-5 illustrate an electronic door lock system 100 . The electronic lock system 100 includes an interior unit 105 and an exterior unit 110 . The electronic lock system 100 is configured to be installed in a variety of doors, such as but not limited to, door 115 , which may be an exterior door or an interior door. The interior unit 105 of the electronic door lock system 100 may be installed on the interior of the door 115 , while the exterior unit 110 may be installed on the exterior of the door 115 . In some embodiments, the lock system 100 may further include a latch 120 assembly. The latch assembly 120 may be a spring-biased latch system, which is known in the art. The illustrated latch assembly 120 includes latch 125 , which is biased in a first direction 130 . In other embodiments, the lock system 100 may include a deadbolt or other known lock mechanisms.
The interior unit 105 may include an interior handle 135 , an interior user interface 140 , an interior input/output (I/O) interface 145 (see FIG. 5 ), and an interior controller 150 (see FIG. 6 ). Although illustrated as a lever, in other embodiments the interior handle 135 may be a knob or other known door handle. When operated by a user, the interior handle 135 will cause the latch 125 to move in a second direction 150 , thus allowing opening of the door 115 .
The exterior unit 110 may include an exterior handle 155 , an exterior user interface 160 , a fingerprint sensor 165 , and an exterior controller 170 ( FIG. 6 ). Although illustrated as a lever, in other embodiments the exterior handle 155 may be a knob or other known door handle. In some embodiments, the exterior handle 155 is in a non-active mode in which actuation of the exterior handle 155 will not cause movement of the latch 125 . However, when in an active mode and actuated by a user, the exterior handle 155 will cause the latch 125 to move in the second direction 150 , thus allowing opening of the door 115 .
FIG. 6 illustrates a block diagram of a control system 200 of the electronic lock system 100 . The control system 200 includes a main controller 205 . The main controller 205 is electrically and/or communicatively connected to a variety of modules or components of the lock system 100 , including, among other things, the interior controller 150 and the exterior controller 170 . The main controller 205 can include any combination of hardware and software operable to, among other things, control operation of the lock system 100 .
In some embodiments, the main controller 205 includes a plurality of electrical and electronic components that provide power, operational control, and protection to the components and modules within the main controller 205 and/or lock system 100 . For example, the main controller 205 includes, among other things, a processing unit, or processor 210 (e.g., a microprocessor, a microcontroller, or another suitable programmable device) and a memory 215 . In some embodiments, the processor 210 and the memory 215 , as well as the various modules connected to the main controller 205 are connected by one or more control and/or data buses. The use of one or more control and/or data buses for the interconnection between and communication among the various modules and components would be known to a person skilled in the art in view of the invention described herein. In some embodiments, the main controller 205 is implemented partially or entirely on a semiconductor (e.g., a field-programmable gate array [“FPGA”] semiconductor) chip, such as a chip developed through a register transfer level (“RTL”) design process.
The memory 215 includes, for example, a program storage area and a data storage area. The program storage area and the data storage area can include combinations of different types of memory, such as read-only memory (“ROM”), random access memory (“RAM”) (e.g., dynamic RAM [“DRAM”], synchronous DRAM [“SDRAM”], etc.), electrically erasable programmable read-only memory (“EEPROM”), flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. In the illustrated embodiment, the processor 210 is connected to the memory 215 and executes software instructions that are capable of being stored in a RAM of the memory 215 (e.g., during execution), a ROM of the memory 215 (e.g., on a generally permanent basis), or another non-transitory computer readable medium such as another memory. Software included in the implementation of the lock system 100 can be stored in the memory 215 of the main controller 205 . The software can include, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The main controller 205 of the illustrated embodiment is configured to retrieve from memory and execute, among other things, instructions related to the control processes and methods described herein. In other constructions, the main controller 205 includes additional, fewer, or different components.
The main controller 205 may be further communicatively coupled to a network communications module 220 . In some embodiments, the network communications module 220 is configured to connect to and communicate through a network 225 . In such embodiments, the network 225 can be configured to connect a plurality of lock systems 100 together. In other embodiments, the plurality of lock systems 100 connect and communicate with each other via respective individual network communications modules 220 (i.e., one for each lock system 100 ). As discussed in further detail below, in such embodiments, the plurality of lock systems 100 creates a mesh network.
In some embodiments, the network 225 is, for example, a wide area network (“WAN”) (e.g., a TCP/IP based network, a cellular network, such as, for example, a Global System for Mobile Communications [“GSM”] network, a General Packet Radio Service [“GPRS”] network, a Code Division Multiple Access [“CDMA”] network, an Evolution-Data Optimized [“EV-DO”] network, an Enhanced Data Rates for GSM Evolution [“EDGE”] network, a 3GSM network, a 4GSM network, a Digital Enhanced Cordless Telecommunications [“DECT”] network, a Digital AMPS [“IS-136/TDMA”] network, or an Integrated Digital Enhanced Network [“iDEN”] network, etc.).
In other embodiments, the network 225 is, for example, a local area network (“LAN”), a neighborhood area network (“NAN”), a home area network (“HAN”), or personal area network (“PAN”) employing any of a variety of communications protocols, such as Wi-Fi, Bluetooth, ZigBee, Z-Wave, etc. Communications through the network 225 by the network communications module 220 or the main controller 205 can be protected using one or more encryption techniques, such as those techniques provided in the IEEE 802.1 standard for port-based network security, pre-shared key, Extensible Authentication Protocol (“EAP”), Wired Equivalency Privacy (“WEP”), Temporal Key Integrity Protocol (“TKIP”), Wi-Fi Protected Access (“WPA”), and the like. The connections between the network communications module 220 and the network 225 are, for example, wired connections, wireless connections, or a combination of wireless and wired connections. Similarly, the connections between the main controller 205 and the network 225 or the network communications module 220 are wired connections, wireless connections, or a combination of wireless and wired connections.
The lock system 100 and/or the main controller 205 receive electrical power from a power supply module 230 . The power supply module 230 supplies a nominal DC voltage to the main controller 205 and other components or modules of the lock system 100 . The power supply module 230 can also be configured to supply lower voltages to operate circuits and components within the main controller 205 or lock system 100 . The power supply module 230 is powered by, for example, one or more batteries or battery packs. In other embodiments, the power supply module 230 is powered by a capacitor, such as a super capacitor or a plurality of capacitors electrically connected in series and/or parallel. Also, in other embodiments, the power supply module 230 is powered by a power source having nominal line voltages between 100V and 240V AC and frequencies of approximately 50-60 Hz. In still other embodiments, the power supply module 230 is powered by Power over Ethernet (PoE), such as but not limited to, PoE 802.3.
In some embodiments, the interior controller 150 and/or the main controller 205 may monitor an electrical characteristic of the power supply. The interior controller 150 and/or the main controller 205 may monitor the voltage, current, and temperature of the batteries or battery pack of the lock system 100 . In such embodiments, the electrical characteristic can be used to determine a remaining battery life. The interior controller 150 and/or main controller 205 may also or instead monitor the nominal line voltage, or input voltage, of the power supply and determine if the power supply has been interrupted.
In some embodiments, the power supply module 230 receives power from a first power source (e.g., wired AC power supply, PoE, etc.), but additionally includes an uninterruptable power supply (“UPS”). In such embodiments, the first power source continually recharges the UPS, and if the first power source is interrupted, the UPS powers the main controller 205 and various components and modules of the lock system 100 . The UPS may be, but is not limited to, one or more batteries, battery packs, or capacitors.
As discussed above, the main controller 205 is communicatively coupled to the interior controller 150 . The interior controller 150 can be substantially similar to the main controller 205 , and can include similar components. The interior controller 150 is further communicatively coupled to the interior user-interface 140 and the interior I/O interface 145 . The interior user-interface 140 may include an interior display 235 and an interior keypad 240 . In some embodiments, the interior display 235 is an organic light-emitting diode (“OLED”) screen. In other embodiments, the interior display 235 may be, among other things, a liquid crystal display (“LCD”), a light-emitting diode (“LED”) display, an electroluminescent display (“ELD”), a surface-conduction electron-emitter display (“SED”), a field emission display (“FED”), and a thin-film transistor (“TFT”) LCD. Although illustrated as only having four keys, the interior keypad 240 may have less or more keys. In other embodiments, the interior user-interface 140 may further include one or more additional indicators, such as but not limited to, speakers.
The interior I/O interface 145 inputs and outputs data to an external device. The interior I/O interface 145 is located on the interior of the door 115 to prevent use from the exterior. In some embodiments, the interior I/O interface 145 is a universal serial bus (“USB”). In other embodiments, the interior I/O interface 145 may be, among other things, Ethernet, serial advanced technology attachment [“SATA”], and integrated drive electronics [“IDE”] interfaces.
As discussed above, the main controller 205 is communicatively coupled to the exterior controller 170 . The exterior controller 170 can be substantially similar to the main controller 205 , and can include similar components. The exterior controller 170 is further communicatively coupled to the exterior handle 155 , the exterior user-interface 160 , and the fingerprint sensor 165 . The exterior user-interface 160 may include an exterior display 245 and an exterior keypad 250 . In some embodiment, the exterior display 245 is an organic light-emitting diode (“OLED”) screen. In other embodiments, the exterior display 245 may be, among other things, a liquid crystal display (“LCD”), a light-emitting diode (“LED”) display, an electroluminescent display (“ELD”), a surface-conduction electron-emitter display (“SED”), a field emission display (“FED”), and a thin-film transistor (“TFT”) LCD. In the illustrated embodiment, the exterior keypad 250 is a numeral keypad, however, in other embodiments, the exterior keypad 250 may include more or less keys. Also, in other embodiments, the exterior user-interface 160 may further include one or more additional indicators, such as but not limited to, speakers.
The electronic lock system 100 having an interior user-interface 140 and an exterior user-interface 160 results in a plurality of benefits, including, but not limited to, simplicity of use and safety. The electronic lock system 100 is simpler than previously known lock system because a user does not have to do all the programming from the outside or the inside. Additionally, the electronic lock system 100 adds a safety component, in that the interior user-interface 140 must be used to add/remove users.
FIG. 7 illustrates the fingerprint sensor 165 . The fingerprint sensor 165 is a fingerprint recognition, or fingerprint authentication, device for sensing and recognizing, or authenticating, one or more fingerprints (e.g., the user's fingerprint). In the illustrated embodiment, the fingerprint sensor 165 is an optical sensor, and includes a touch surface 255 . The illustrated fingerprint sensor 165 captures a digital image of the fingerprint placed at the touch surface 255 . Beneath the touch surface 255 is a light-emitting phosphor layer which illuminates the surface of the finger. The light reflected from the finger passes through the phosphor layer to an array of solid state pixels (a charge-coupled device) which captures a visual image of the fingerprint. The visual image of the fingerprint is then sent to the exterior controller 170 and/or the main controller 205 for analysis. In other embodiments, the fingerprint sensor 165 may be, but is not limited to, an ultrasonic sensor, a resistive sensor, or a capacitance sensor.
FIG. 8 illustrates one embodiment of operation 300 of the electronic door lock system 100 , in which a user stores individual fingerprint data. Although illustrated as occurring in a sequential order, it should be understood that the order of the steps disclosed in operation 300 may vary. Furthermore, additional steps may be included in the operation 300 , and not all of the steps may be required. Operation 300 begins with the user turning on, or waking up, the lock system 100 by pressing a key of keypad 240 (Step 305 ). The user then accesses a main menu on one of the interior user-interface 140 or exterior user-interface 160 (Step 310 ). In some embodiments, the main menu is accessed via an administrator password entered via one of the interior keypad 240 or exterior keypad 250 . Once the user has accessed the main menu, the user must program his or her fingerprint data. This is performed by placing the user's finger onto the touch surface 255 when prompted by one of the interior display 235 and the exterior display 245 (Step 315 ). In some embodiments, the lock system 100 may prompt the user to place his or her finger onto the touch surface 255 a plurality of times and/or in a plurality of finger positions. The fingerprint data is sent from the fingerprint sensor 165 to the exterior controller 170 (Step 320 ), which stores the fingerprint data (Step 325 ). Alternatively, or in conjunction to Step 325 , the exterior controller 170 may send the fingerprint data to the main controller 205 for storage.
FIG. 9 illustrates another embodiment of operation 400 , in which a user operates the lock system 100 using the fingerprint sensor 165 . Although illustrated as occurring in a sequential order, it should be understood that the order of the steps disclosed in operation 400 may vary. Furthermore, additional steps may be included in the operation 400 , and not all of the steps may be required. Operation 400 begins with the user waking up the lock system 100 by pressing a key of keypad 250 (Step 405 ). The exterior display 245 prompts the user to place his or her finger on the touch surface 255 (Step 410 ). The fingerprint sensor 165 captures the visual image of the fingerprint and sends the visual image to the exterior controller 170 as fingerprint data (Step 415 ). The exterior controller 170 communicates with the main controller 205 to determine if the fingerprint data matches any stored finger print data (Step 420 ). If the fingerprint data does match stored fingerprint data, the exterior controller 170 receives an active signal from the main controller 205 and activates the exterior handle 155 (Step 425 ). The user may then operate the exterior handle 155 to gain access through the door 115 (Step 430 ). If the fingerprint data does not match any stored fingerprint data in Step 420 (or in some embodiments matches fingerprint data of users who are not authorized), then the exterior controller 170 sends a signal to the exterior display 245 notifying the user (Step 435 ). In other embodiments discussed in more detail below, after determining that the fingerprint data matched stored fingerprint data, the main controller 205 and/or exterior controller 170 may further determine if the user is allowed access at that specific time of day, based on a use-schedule.
FIG. 10 illustrates another embodiment of operation 500 , in which a user stores fingerprint data and/or use-schedules for a plurality of users. Although illustrated as occurring in a sequential order, it should be understood that the order of the steps disclosed in operation 500 may vary. Furthermore, additional steps may be included in the operation 500 , and not all of the steps may be required. Use-schedules may include a plurality of access times for a plurality of users. By way of example only, a use-schedule may include specific times of day, specific days, and/or specific dates in which individual users are allowed access.
Operation 500 begins with the user turning on, or waking up, the lock system 100 by pressing a key of keypad 240 or keypad 250 (Step 505 ). The user then connects an external device (e.g., a USB memory stick, an external computing device, etc.) to the interior controller 150 via the interior I/O interface 145 (Step 510 ). The user follows on-screen instructions on either the interior display 235 or the exterior display 245 (Step 515 ). The fingerprint data and/or use-schedules are received by the interior controller 150 via the interior I/O interface 145 (Step 520 ). The fingerprint data and/or use-schedules are then sent to the main controller 205 (Step 525 ).
FIG. 11 illustrates another embodiment of operation 600 , in which the lock system 100 receives fingerprint data and/or use-schedules via the network communications module 220 . Although illustrated as occurring in a sequential order, it should be understood that the order of the steps disclosed in operation 600 may vary. Furthermore, additional steps may be included in the operation 600 , and not all of the steps may be required. Operation 600 begins with a user entering fingerprint data and/or use-schedules at an external computer (Step 605 ). The user then sends the fingerprint data and/or use-schedules to the lock system 100 via the network 225 (Step 610 ). As discussed above, in some embodiments, the network 225 may include be a mesh network (e.g., a wireless mesh network, such as but not limited to a wireless network using a Z-Wave communications protocol), which includes a plurality of other lock systems 100 . In such embodiments, the network 225 may use an algorithm to determine the best path for transmitting the data (e.g., fingerprint data, use-schedules, etc.) between the lock systems in order to achieve faster communication, and/or conserve battery life of the individual lock systems 100 . In some embodiments, the algorithm is based at least in part upon the physical distance each individual lock system is away from one or more other lock systems 100 in the network. The algorithm may also or instead be based at least in part upon the remaining battery life of each individual lock system, which information is provided from individual lock systems 100 across the network as needed. In some embodiments, the algorithm is based at least in part upon both the physical distances between lock systems 100 in the network and the remaining battery lives of each of the lock systems 100 . The individual lock system 100 receives the fingerprint data and/or the use-schedules via the network communications module 220 (Step 615 ). The fingerprint data and/or use-schedules are stored by the main controller 205 (Step 620 ).
FIG. 12 illustrates one embodiment of a mesh network 700 . The mesh network 700 includes a plurality of nodes A-O. In some embodiments, each of the plurality of nodes A-O is an individual lock system 100 described and illustrated herein. In other embodiments, the plurality of nodes A-O include one or more external computing devices and one or more individual lock systems 100 described and illustrated herein. The plurality of nodes A-O is configured to communicate with each other through the mesh network 700 . By way of example only and with reference to FIG. 12 , node A is configured to communicate with node K; node L is configured to communicate with node H; etc. In some embodiments, the communication path between nodes is determined using signal strength, which is indicative of distances between nodes. In these and other embodiments, the communication path between nodes is determined using signal strength and an error rate of a test signal sent between nodes. In such embodiments, the signal strength along with the error rate of a test signal are used to determine a wireless transmission efficiency between nodes. Typically, a higher error rate means more drain on a battery of an individual lock system 100 during wireless communication. Therefore, in some embodiments, although a first communication path may be physically shorter than a second communication path, the second communication path may have a lower error rate. Thus, efficiency may determine that the second communication path will be used.
By determining the communication path using signal strength and/or the efficiency between nodes, battery life of the individual lock systems 100 is increased. In some embodiments, battery life of the individual lock systems 100 is monitored. In such embodiments, if the remaining battery life of an individual lock system 100 is below a threshold, the individual lock system 100 will not be used for communication within the mesh network 700 .
FIG. 13 illustrates a process 800 , or communication protocol, for determining a communication path between nodes of the mesh network 700 . Although illustrated as occurring in a sequential order, it should be understood that the order of the steps disclosed in operation 800 may vary. Furthermore, additional steps may be included in the operation 800 , and not all of the steps may be required in some embodiments. In some embodiments, all of the nodes typically operate in a “sleep mode” until they are awoken by a user or by another node. The process 800 begins by a user waking a primary node (e.g., node A) (Step 805 ). The primary node sends out a query to a plurality of secondary nodes within range (e.g., node B, node C, node D, node E of FIG. 12 ) (see Step 810 of FIG. 13 ). The secondary nodes wake up and reply to the primary node with an identification number or other data. The reply with the identification number allows the primary node to know what nodes exist within range of the primary node. The process 800 determines if the target node is within range (Step 815 ). If the target node is in range, data communication occurs between the primary node and the target node (Step 825 ). If the target node is not in range, a communication is performed between the primary node and the secondary nodes to determine signal strengths (and/or in some embodiments, error rates) of each second node (Step 830 ). The primary node creates a table or other aggregation or listing of data of identification numbers of the secondary nodes with the respective signal strengths and/or error rates (e.g., efficiency between nodes) (Step 835 ). A leg of the communication path is then chosen based at least in part upon the efficiency between the primary node and secondary nodes (Step 840 ). Once a secondary node is chosen based at least in part upon efficiency, and thus a first leg of the communication path is chosen, the process returns to Step 810 , and the chosen secondary node becomes the primary node.
In other embodiments, the primary node outputs a query to a plurality of secondary nodes within range. The secondary nodes then output queries to a plurality of tertiary nodes within range. This occurs until all of the nodes are queried and reply back with respective identification numbers or other identification data. Communication through the mesh network is then performed between the primary node and the secondary nodes, tertiary nodes, etc., in order to determine the respective signal strengths and/or error rates as described above. A complete efficiency table (or other aggregation of this data) is then created for all of the nodes within the mesh network. The communication path between the primary node and the target node is then chosen using the complete efficiency table.
FIG. 14 illustrates an exemplary embodiment of a software decision tree 900 for the electronic lock system 100 . In this illustrated embodiment, a user wakes up the electronic lock system 100 by activating the interior user-interface 140 or the exterior user-interface 160 (box 905 ). The electronic lock system 100 queries the user for a password and/or fingerprint data (box 910 ). The electronic lock system 100 determines if the password and/or fingerprint data is correct (box 915 ). If the password and/or fingerprint data is incorrect, an error message is displayed, and the software returns to Box 910 . If the password and/or fingerprint data is correct, the MAIN MENU is displayed (Box 920 ). The user can then select a plurality of options from the MAIN MENU, including but not limited to, LOCK SETUP (box 925 ), USER EDIT (box 930 ), UPLOAD USERS/SCHEDULES (Box 935 ), LOCK ACTIVITY (Box 940 ), and HARD RESET (Box 945 ). The LOCK SETUP (Box 925 ) allows the user to set up the lock (e.g., set the date and time of the lock, sensitivity of the fingerprint sensor 165 , brightness of interior display 235 , brightness of exterior display 245 , etc.). The USER EDIT (Box 930 ) allows the user to add, delete, and modify user information (e.g., user passwords, user fingerprint data, user schedules, etc.) of the electronic lock system 100 . The UPLOAD USERS/SCHEDULES (Box 935 ) allows a user to upload a plurality of user information (e.g., user passwords, user fingerprint data, user schedules, etc.) as discussed above in more detail. The LOCK ACTIVITY (Box 940 ) allows the user to view and/or download the activity of the electronic lock system 100 (e.g., activation dates/times of the electronic lock system 100 , usage occurrences, use dates and time, use dates and time of particular users, and the like). The HARD RESET (Box 945 ) resets the electronic lock system 100 .
In some embodiments, the lock system 100 only includes the main controller 205 , and not an interior controller 150 and/or an exterior controller 170 . In such embodiments, the main controller 205 may perform the functions of the internal controller 150 and/or the exterior controller 170 mentioned above. In some embodiments, the lock system 100 includes main controller 205 , interior controller 150 , and the exterior controller 170 , and at least two of the three controllers are part of a common controller, which performs all of the functions described above of at least two of the three controllers.
Thus, some embodiments of the invention provide, among other things, an electronic lock system having a fingerprint sensor, mesh network capability, and a wireless power supply. Various features and advantages of the invention are set forth in the following claims. | Electronic locks, electronic lock systems, and electronic lock networks are provided, and can include a latch, an interior unit including an interior handle operable to place the latch in the unlatched position, an interior user-interface, and an interior controller coupled to the interior user-interface; an exterior unit including an exterior handle having an active mode and a non-active mode, the exterior handle operable to place the latch in the unlatched position when in the active mode, an exterior user-interface, a fingerprint sensor configured to sense fingerprint data, and an exterior controller configure to receive the sensed fingerprint data, output the sensed fingerprint data, and place the exterior handle in the active mode upon receiving an active signal; and a main controller coupled to the interior controller and the exterior controller, the main controller configured to receive the sensed fingerprint data from the exterior controller, compare the sensed fingerprint data to a known fingerprint data, and output the active signal to the exterior controller based on the comparison. | 4 |
RELATED APPLICATIONS
This application is a continuation-in-part application of U.S. Ser. No. 667,762 filed on Nov. 2, 1984.
BACKGROUND OF THE DISCLOSURE
Conventional methods for servicing safety relief valves typically require awkward and expensive piping fabrications or even total shutdown of the system for routine or emergency service of redundant safety relief valves. Some conventional methods require two separate penetrations into the pressure vessel connected with mechanically linked block valves. Other conventional methods incorporate three-way block valves connected to a single penetration into the pressure vessel. The three-way block valve configuration commonly results in high pressure losses. The valve selector manifold of the present disclosure overcomes the disadvantages associated with these conventional methods.
This apparatus is directed to a valve mounting manifold. It is adapted to be attached to a pressure vessel for protection of the vessel against overpressure. It is duplicate valved to enable relief devices to be installed with only a single opening into the pressure vessel thereby reducing the number of openings formed in the pressure vessel. It is axiomatic that openings cut into a pressure vessel, cause problems by increasing complexity, all at an increased cost. This device enables the number of openings cut into a pressure vessel to be reduced. It defines a pressure vessel selector manifold enabling multiple safety relief valves to be installed at a single vessel opening. The valve selector manifold of this disclosure enables one safety valve to be placed in service while a second valve is out of service or even dismounted for maintenance.
The dual active valve selector manifold of this disclosure provides dual connections for relief during flowing conditions. This manifold has smoothly faired flow paths to the selected relief valves and thereby enables the relief valves to be exposed to the pressure of the vessel with minimum pressure loss during flowing conditions.
Pressure vessels typically require one or more safety relief valves for protection of the vessel in the event of overpressure. The selector valve manifold of this disclosure is particularly suitable for use with pressure vessels requiring two safety relief valves in operation to meet the safety standards established for the pressure vessel. The selector manifold of this disclosure is dual active, permitting both safety relief valves to be exposed to the pressure of the pressure vessel simultaneously through a single opening into the pressure vessel.
Periodic maintenance or repairs of the safety relief valves will be required. The valve selector manifold of this disclosure enables field servicing of one relief valve without defeating safety valve protection of the pressure vessel by the second relief valve. For instance, this device mounts duplicate safety relief valves, enabling one to be switched out of service while the other remains operative. Removal of one can be undertaken while the other is operative. This can be accomplished without reducing pressure in the pressure vessel.
SUMMARY OF THE INVENTION
With the foregoing in view, the present apparatus is described in summary fashion as incorporating a flange connector adapted to be joined to a pressure vessel at a flanged opening. The flange encloses a passage of specific diameter. The housing encloses alternative flow paths. The alternate flow paths are selected by rotating a rotor mounted on a central pin for rotation, creating alternate flow paths through the selector valve manifold. The flow paths are routed to a top plate, the top plate having spaced openings to enable similar or identical safety relief valves to be mounted on top of the selector valve manifold. A closure disc mounted on the rotor enables alternate closing of the flow passages permitting maintenance and repair of the relief valves mounted to the selector valve manifold. When maintenance or other service is not required, the rotor is positioned so that both flow passages to the safety relief valves are open.
Many other details will be observed upon review of the description below of the preferred and illustrated embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is a sectional view through the selector valve manifold of the invention showing details of constructions;
FIG. 2 is a top view of the rotor member of the invention;
FIG. 3 is a sectional view through the selector valve manifold showing that the both flow paths are open through the manifold;
FIG. 4 is a sectional view taken along line 2--2 of FIG. 1; and
FIG. 5 is a sectional view of the closure disc for selectively closing the flow paths of the selector manifold.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 of the drawings, the numeral 10 identifies the complete assembly which comprises the selector manifold apparatus of this disclosure. The apparatus 10 includes a circular flange body component 12 which will be described as the lower body portion. It terminates at a transverse flat face 14; the flat face 14 being adapted to abut a matching face of an upstanding and encircling upper body component 16. As will be observed, they are joined together by suitable headless bolts 18, and a suitable inlet opening is defined at 20. The inlet opening 20 is adapted to be connected by any suitable means, including a matching flange whereby connection is made to a pressure vessel or the like.
Centrally located within the two housing components 12 and 16 is a rotatable component. It is captured within the two housing components and is enclosed in a pressure type chamber 22. More accurately, it is enclosed in the two housing components when assembled so that it operates to divert the flow therethrough along a route to one or both of the safety relief valves. The rotatable component, which for purposes of convenience, will be described as a rotor, is generally identified by the numeral 24, shown in FIG. 2. The rotor 24 is preferably formed as casting and incorporates three curving conduits 26, 28 and 30 therein. The conduits 26, 28 and 30 terminate or merge at the common inlet end 32 of the rotor 24. The inlet end 32 is telescoped adjacent the inlet opening 20 of the lower housing component 12. The inlet 32 has an internal diameter sized to be equal to or larger than the mating outlet in the pressure vessel opening. Moreover, the inlet 32 has an internal diameter which is larger than the internal diameter at the outlet end of the curving conduits 26, 28 and 30 and sized so that there is minimum constriction to fluid flow, thereby obtaining minimum pressure drop between the inlet and outlets of the apparatus 10.
Referring now to FIG. 1, the curved conduit 28 is shown terminating at an outlet end 29. The end 29 is spaced from a circular, axially hollow seat assembly 35. The seat assembly 35 is spaced from the end 29 of the curved conduit 28. The seat assembly 35 has a downwardly directed face 33 for sealing purposes. A fluid tight seal between the seat assembly 35 and the upper housing component 16 is provided by a seal ring 37.
The upper housing 16 includes a curved passage 17. The passage 17 extends upwardly as shown in FIG. 1 where it exposes an open upper end and is conveniently welded to a flanged fitting 36 for connection with a pressure relief valve. The passage 17 may capture fluid under pressure between the relief valve connected at the flanged fitting 36 and the valve seat assembly 35. To this end, the numeral 38 identifies a hand valve which opens into the passage 17. The hand valve 38, when opened, permits trapped pressure in the passage 17 to be released. In addition, the hand valve 38 provides an inlet to the passage 17 testing the relief valve connected at the flanged fitting 36.
As described at this juncture, it will be understood that duplicate equipment is arranged on both the right and left as shown in FIG. 1. That is, there is a similar left seat assembly 35 cooperative with a similar left side passage 17 for convenient connection to a similar safety relief valve. Moreover, the left hand passage is protected by a suitable hand valve 38 permitting access to that passage. Likewise, the curving conduits 26, 28 and 30 are substantially identical curving upwardly and outwardly from the common inlet 32. The curved conduits 26 and 30 terminating at outlet ends 27 and 31, respectively.
The conduits 26, 28 and 30 and the passages 17 form a smooth, gently curving flow passage for directing fluid flow from the pressure vessel outlet to the pressure relief valves connected at the flanged fittings 36. Obstructions or abrupt changes in flow direction are avoided. The curving flow passages permits a smooth change in direction of fluid flow through the apparatus 10 with minimum pressure drop between the inlet and outlets of the apparatus 10.
The rotor 24 is preferably formed as casting, incorporating the curved conduits 26, 28 and 30, and the inlet 32 therein. The rotor 24 also includes an upstanding circular sleeve 39 extending from the upper domed end of the rotor 24. The sleeve 39 defines a blind hole sized to receive the lower end of a rotatable pin 42. A hole through the sleeve 39 enables a bolt 40 to be anchored through the sleeve 39 and to the lower end of the rotatable pin 42. The pin 42 supports a downwardly protruding lug 34 which is perforated to align with the hole in the sleeve 39 for receiving the bolt 40 therethrough. The bolt 40 fastens at a specified elevation to support in a hanging or downwardly depending position the rotor 24. The rotor 24 has a center line axis of rotation defined by the mounting pin 42 and it is axially coincident with the inlet opening at 20 and the inlet 32 of the rotor 24. Accordingly, the rotor 24 rotates to position the curved conduits 26, 28 and 30 in alignment with the passages 17 shown in FIGS. 1 and 3. The curved conduits rotate about the axis defined by the pin 42 so that each curved conduit can be aligned with the left or right passages in the upper housing 16 as desired. A separate construction supports a closure member on the rotor 24. The passages 17 in the upper housing 16 are aligned at approximately 180° on opposite sides from the pin 42. The closure member and the curved conduits 26, 28 and 30 are aligned at 90° spacing about the rotational axis of the rotor 24.
This kind of arrangement utilizes the rotor 24 to rotate the curved conduits 26, 28 and 30 to a desired alignment as illustrated in FIGS. 1 and 3. Curved conduits 26 and 30 are aligned at 180° spacing permitting fluid flow through both passages 17 upon rotation of the rotor 24 in the position illustrated in FIG. 3. The curved conduit 28 is aligned 180° from the closure disc 44. The closure disc 44 is mounted on a telescoping mounting pin 46. A mounting plug 45 is threaded to the rotor 24, as best shown in FIG. 5, for mounting the closure disc 44 to the rotor 24. The pin 46 extends through the mounting plug 45 and is threaded to the closure disc 44. The pin 46 is axially hollow at 47. It is hollow from the exposed end back to the recessed end as shown in FIG. 5. A lateral passage 48 aids in permitting fluid to flow through the pin 46. The pin 46 is permitted to move relative to the mounting plug 45 so that the closure disc 44 wobbles slightly when not sealed against the face 33 of the seat assembly 35. This permits the closure disc 44 to accommodate for slight misalignment with the seat assembly 35. Upon slight downward movement of the rotor 24, a gap is formed at 49 establishing fluid communication between the interior chamber 22 and the passage 17. The flow path is through the gap at 49 past seal ring 50. The flow path in the vicinity of the pin 46 is directed along the pin 46 through passage 47 and out into the passages 17.
The closure disc 44 incorporates a peripheral seal 52. The seal 52 is included to seal against the face 33 of the seat assembly 35. Assuming a pressure differential acting on the closure disc 44, it seals at the face 33 with the seal ring 52, and flow is prevented through the blocked axial passages 17 when the rotor 24 is in the up position illustrated in FIG. 1. When the rotor 24 moves downwardly, the seal system is broken whereby flow can occur through the gap 49.
As will be understood, the closure disc 44 can be raised or lowered. It is shown in the sealing and raised position in FIGS. 1 and 5. Lowering the rotor 24 breaks the seal at 49 thereby permitting the pressure in the chamber 22 to be transmitted to the opposite side of the closure disc 44 via the passage 47 in pin 46. Thus, the pressure is equalized across the closure disc 44 breaking the seal with the face 33 of the seat assembly 35; thereby freeing the closure disc 44 for easy disengagement and rotation. When disengaged, the disc 44 may be rotated 180° over to the other passage 17 so that the safety relief valve connected thereto may be serviced, if required. If additional service or repair is not required, the closure disc 44 is rotated 90° for aligning the curved conduits 26 and 30 with the passages 17 for normal operation of both safety relief valves. As will be understood, the rotor 24 can be rotated with no flow or during full flow, thereby interrupting full flow to only one of the safety relief valves at a time so that a safety relief valve is operationally connected to the pressure vessel at all time.
Referring again to FIG. 1 the mounting pin 42 will be described in greater detail. First of all, a seal about the mounting pin 42 is defined at 54. A stack of seal members is compressed by capture ring 56. The capture ring 56 is jammed downwardly by a flanged jam member 58. The jam member 58 is pulled downwardly by suitable bolts 59 which thread into the upper housing 16. A portion of the pin 42 extends above the upper housing 16 and is readily accessible.
The mounting pin 42 extends upwardly through a sleeve 60. The sleeve 60 is fixedly anchored by an inverted U-shaped mounting bracket or the like connected by suitable nuts and bolts to the upper housing 16. This clamps the sleeve 60 in location. That is, the sleeve 60 is fixed at an elevation which is specified by the U-shaped mounting clamp on it and is not able to move. In this fixed elevation, the sleeve 60 supports an external threaded sleeve 62. The sleeves 60 and 62 are threaded together as shown in FIG. 1. The sleeve 62 in turn supports an external sleeve 64 joined thereto by a set screw 65. The set screw 65 is included to lock the sleeves 62 and 64 together.
The mounting pin 42 includes a circumferential groove 66 adjacent its upper end for receiving suitable ball bearings 67 therein. The ball bearings 67 are engaged by a lock nut 68 thereabove. The sleeves 62 and 64 and the lock nut 68 form a rotatable assembly 69 which may be grasped and rotated. Rotation is accomplished at the threaded interconnection 63 between the sleeves 60 and 62. The rotatable lock assembly 69 may be rotated clockwise or counter clockwise, thereby driving the rotating components shown around the pin 42 imparting such threaded rotation through the ball bearings 67. Rotation of the rotatable assembly 69 accomplishes raising and lowering of the mounting pin 42. The mounting pin 42 serves as an axis of rotation. The pin 42 is able to travel downward slightly, it being observed that the rotor 24 terminates in a telescoping connecting between the inlet 32 of the rotor 24 and the inlet 20 of the lower body 12. Downward movement of the mounting pin 42 forces the rotor 24 downwardly, thereby breaking the seal at 49 and permitting equalizing pressure across the closure disc 44 in the manner described above. Axial displacement of the mounting pin 42 also assures clearance between the rotor 24 and the body 16 during rotation of the rotor 24.
Rotation of the assembly 69 at the top of the mounting pin 42 accomplishes an unlocking function. The numeral 70 identifies a locking lug which protrudes radially inwardly from the surrounding lower body component 12. The rotor 24 supports a collar 71 which extends partially around the lower end thereof. The collar 71 has a top face or surface 72. When the rotor 24 is forced downwardly, the top surface 72 is located below the lug 70 whereby relative rotation is permitted. The collar 71 is slotted at 74, thereby permitting the lug 70 to move relatively upwardly and downwardly in the slot 74 to assure proper alignment of the curved conduits 26 and 30, as shown in FIG. 3. A pair of stop lugs 76 are located on the rotor 24. The stop lugs 76 extend above the surface 72 of the collar 71 providing an abutment surface for limiting rotational movement of the rotor 24. A stop lug is located adjacent each end of the collar 71 and spaced therefrom defining a slot 78, thereby permitting the lug 70 to move relatively upwardly and downwardly in the slot 78. In this manner, rotational movement of the rotor 24 is limited to about 180° in either direction to bring the lug 70 into either extremity of its permitted movement. The slots 74 and 78 are positioned to assure that proper alignment of the rotor 24 relative to the passages 17 is accomplished.
The arrangement just described accomplishes vertical translation of the rotor 24, all accomplished without leakage along the pin 42, for the purpose of breaking or making the seal at the closure disc 44 and to assure clearance of the rotor 24 with the body 16 during subsequent rotation.
Operation of the apparatus 10 is accomplished by first rotating the lock assembly 69 for imparting axial movement to the mounting pin 42. Recall that the sleeve 60 is fixed in elevation so that relative rotation of the lock assembly 69 forces the mounting pin 42 downwardly or upwardly depending on the direction of rotation. Once the mounting pin 42 and thereby the rotor 24 has been moved downwardly, the lug 70 is then located above the collar 71 and is able to slide along the top surface 72 thereof. Moreover, the gap 49 is opened, permitting pressure equalization across the closure disc 44. The rotor 24 is then rotated to the desired position aligning the curved conduits 26, 28 and 30 relative to the passages 17 for communicating fluid pressure to the safety relief valves.
Alignment of the curved conduits also align the lug 70 with one of the slots 74 and 78 of the collar 71. The lock assembly 69 is again rotated to pull the rotor 24 upwardly and thereby position the lug 70 in the aligned slot 74 or 78. This locks the rotor 24 in position and prevents relative rotation of the rotor 24 within the housing chamber 22. If the rotor 24 is rotated to close one of the passages 17 as shown in FIG. 1, upward movement of the rotor 24 closes the gap at 49 and forces the closure disc 44 against the face 33 of the seat assembly 35.
The chamber 22 is pressurized by fluid pressure entering the chamber 22 through the curved conduits 26 and 30 when the rotor 24 is rotated to the position shown in FIG. 1. Pressurization of the chamber 22 forces the closure disc 44 against the seal assembly 35 and thereby perfecting a fluid tight seal at seal ring 52.
Referring now to FIG. 3, the rotor 24 is positioned so that both passages 17 are open. The safety relief valves mounted to the apparatus 10 are thus both exposed to fluid pressure of the pressure vessel for protection of the vessel in the event of overpressure. This is the normal operational position of the dual active selector valve manifold of the present disclosure.
The apparatus 10 has been described herein for use in conjunction with safety relief valves. This disclosure, however, is not limited to use solely with safety relief valves. Operation of the apparatus 10 can be performed with full fluid flow through both of the passages 17. Therefore, use of the apparatus 10 in a diverter-type application for fluid flow. Use of the apparatus 10 as a diverter valve or the like for directing fluid flow is contemplated herein and is within the scope of this disclosure.
While the foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims which follow. | A dual active selector valve is set forth. In the preferred and illustrated embodiment, a flange supporting a manifold body is attached to a pressure vessel. The passage through the flange has a selected diameter and the manifold body opens out to a larger diameter, sufficient to enable two valves to be connected side by side, having inlet passages equal in diameter to about one half the selected diameter. A rotatable conduit member is mounted within the manifold body having a centrally located pin for rotation, the rotatable portion incorporating separate flow passages selectively connecting to one of the two alternately deployed valves, and also supporting a valve closure plate to plug the passageway into the valve not being used. | 5 |
This application is a division of application Ser. No. 10/042,164, filed Jan. 11, 2002, now U.S. Pat. No. 6,569,470, which is a division of Ser. No. 09/325,852, filed Jun. 4, 1999, now U.S. Pat. No. 6,350,479, which claims priority under 35 U.S.C. § 119(e) to Provisional Application No. 60/088,117, filed Jun. 5, 1998.
FIELD OF THE INVENTION
The present invention relates to the novel use of compounds and substances which are capable of modulating monoamine oxidase (MAO) activity by inhibiting the MAO enzyme. The present invention also relates to MAO inhibitors and their therapeutic use as a drug or dietary supplement in the treatment of various conditions or disorders, including psychiatric and neurological illnesses. More particularly, the present invention relates to the therapeutic use of tobacco alkaloids, Yerbamaté ( Ilex paraguariensis ) extract, or tobacco extracts to inhibit MAO activity to provide a treatment for various disorders or conditions.
BACKGROUND OF THE INVENTION
By inhibiting MAO activity, MAO inhibitors can regulate the level of monoamines and their neurotransmitter release in different brain regions and in the body (including dopamine, norepinephrine, and serotonin). Thus, MAO inhibitors can affect the modulation of neuroendocrine function, respiration, mood, motor control and function, focus and attention, concentration, memory and cognition, and the mechanisms of substance abuse. Inhibitors of MAO have been demonstrated to have effects on attention, cognition, appetite, substance abuse, memory, cardiovascular function, extrapyramidal function, pain and gastrointestinal motility and function. The distribution of MAO in the brain is widespread and includes the basal ganglia, cerebral cortex, limbic system, and mid and hind-brain nuclei. In the peripheral tissue, the distribution includes muscle, the gastrointestinal tract, the cardiovascular system, autonomic ganglia, the liver, and the endocrinic system. The present invention overcomes the problems and limitations of the prior art by providing methods and systems.
MAO inhibition by other inhibitors have been shown to increase monoamine content in the brain and body. Regulation of monoamine levels in the body have been shown to be effective in numerous disease states including depression, anxiety, stress disorders, diseases associated with memory function, neuroendocrine problems, cardiac dysfunction, gastrointestinal disturbances, eating disorders, hypertension, Parkinson's disease, memory disturbances, and withdrawal symptoms.
It has been suggested that cigarette smoke may have irreversible inhibitory effect towards monoamine oxidase (MAO). A. A. Boulton, P. H. Yu and K. F. Tipton, “Biogenic Amine Adducts, Monoamine Oxidase Inhibitors, and Smoking,” Lancet, 1(8577): 114-155 (Jan. 16, 1988), reported that the MAO-inhibiting properties of cigarette smoke may help to explain the protective action of smoking against Parkinson's disease and also observed that patients with mental disorders who smoke heavily do not experience unusual rates of smoking-induced disorders. It was suggested that smoking, as an MAO inhibitor, may protect against dopaminergic neurotoxicity that leads to Parkinson's disease and that the MAO-inhibiting properties of smoking may result in an anti-depressive effect in mental patients.
L. A. Carr and J. K. Basham, “Effects of Tobacco Smoke Constituents on MPTP Induced Toxicity and Monoamine Oxidase Activity in the Mouse Brain,” Life Sciences, 48:1173-1177 (Jan. 16, 1991), found that nicotine, 4-phenylpyridine and hydrazine prevented the decrease in dopamine metabolite levels induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice, but there was no significant effect on dopamine levels. Because tobacco smoke particulate matter caused a marked inhibition of MAO A and MAO B activity when added in vitro, it was suggested that one or more unidentified substances in tobacco smoke are capable of inhibiting brain MAO and perhaps altering the formation of the active metabolite of MPTP.
J. S. Fowler, N. D. Volkow, G. J. Wang, N. Pappas, and J. Logan, “Inhibition of Monoamine Oxidase B in the Brain of Smokers,” Nature (Lond), 379(6567):733-736 (Feb. 22, 1996), found that the brains of living smokers showed a 40% decrease in the level of MAO B relative to non-smokers or former smokers. MAO inhibition was also reported as being associated with decreased production of hydrogen peroxide.
It has also been suggested that nicotine may not be the only constituent of tobacco responsible for tobacco addiction. J. Stephenson, “Clues Found to Tobacco Addiction,” Journal of the American Medical Association, 275(16): 1217-1218 (Apr. 24, 1996), discussing the work of Fowler, et al., pointed out that the brains of living smokers had less MAO B compared with the brains of nonsmokers or former smokers. MAO B is an enzyme involved in the breakdown of dopamine, which is a pleasure-enhancing neurotransmitter. The results suggested that the inhibition of MAO B in the brains of smokers may make nicotine more addictive by slowing down the breakdown of dopamine, thereby boosting its levels. The findings provided an explanation as to why cigarette smokers were less susceptible to developing Parkinson's disease. Further, the findings suggested that MAO inhibitors could be used for smoking cessation.
K. R. R. Krishnan, “Monoamine Oxidase Inhibitors,” The American Psychiatric Press Textbook of Pharmacology, American Psychiatric Press, Inc., Washington, D.C. 1995, pp. 183-193, suggest various uses for monoamine oxidase inhibitors. The uses include atypical depression, major depression, dysthymia, melancholia, panic disorder, bulimia, atypical facial pain, anergic depression, treatment-resistant depression, Parkinson's disease, obsessive-compulsive disorder, narcolepsy, headache, chronic pain syndrome, and generalized anxiety disorder.
D. Nutt and S. A. Montgomery, “Moclobemide in the Treatment of Social Phobia,” Int. Clin. Psychopharmacol, 11 Suppl. 3: 77-82 (Jun. 11, 1996), reported that moclobemide, a reversible MAO inhibitor, may be effective in the treatment of social phobia.
I. Berlin, et al., “A Reversible Monoamine Oxidase A Inhibitor (Moclobemide) Facilitates Smoking Cessation and Abstinence in Heavy, Dependent Smokers,” Clin. Pharmacol. Ther., 58(4): 444-452 (October 1995), suggested that a reversible MAO A inhibitor can be used to facilitate smoking cessation.
U.S. Pat. No. 3,870,794 discloses the administering of small quantities of nicotine and nicotine derivatives to mammals, including humans, to reduce anger and aggressiveness and to improve task performance.
U.S. Pat. No. 5,276,043 discloses the administering of an effective amount of certain anabasine compounds, certain unsaturated anabasine compounds, or unsaturated nicotine compounds to treat neurodegenerative diseases.
U.S. Pat. No. 5,516,785 disclose a method of using anabasine, and DMAB anabasine for stimulating brain cholinergic transmission and a method for making anabasine.
U.S. Pat. Nos. 5,594,011, 5,703,100, 5,705,512, and 5,723,477 disclose modulators of acetylcholine receptors.
Known irreversible MAO inhibitors also inhibit MAO in the stomach and liver as well as the brain. As a result, their use has been limited because hypertensive crisis may occur when certain types of food (for example, fermented foods) are ingested, thereby creating an adverse drug-food interaction. Tyramine, which has a pressor action and which is normally broken down by the MAO enzymes, can be present in certain foods.
Thus, it would be desirable to provide MAO inhibitors which are effective, but less potent (i.e., those which provide an asymptotic effect on MAO inhibition) than known MAO inhibitors, for the treatment-of various conditions and disorders. It would also be desirable to provide MAO inhibitors which are easily synthesized and which could be provided to patients as an “over the counter” medication or dietary supplement.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to the discovery that certain tobacco alkaloids or extracts, a certain tea plant extract, and a certain extract of tobacco extract-containing chewing gum and lozenges provide MAO-inhibiting effects. The present invention also relates to the use of these compounds or substances in the treatment of certain conditions and disorders in mammals, including humans.
The compounds and substances of the present invention are capable of inhibiting MAO activity in mammalian brain and peripheral tissue. These compounds and substances act by increasing the concentration of monoamine compounds (norepinephrine, dopamine, and serotonin) in the body and brain.
The present invention provides a method of treating certain medical, psychiatric and/or neurological conditions or disorders. In a first embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of anabasine, anatabine or nornicotine to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
In a second embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of Yerbamaté ( Ilex paraguariensis ) tea plant to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
In a third embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of a tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
In a fourth embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of gum and lozenges formulated with tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a plot of MAO inhibition versus time for anabasine.
FIG. 2 shows the inhibition of MAO A and MAO B for anabasine.
FIG. 3 shows a plot of MAO inhibition versus time for anatabine.
FIG. 4 shows the inhibition of MAO A and MAO B for anatabine.
FIG. 5 shows a plot of MAO inhibition versus time for nornicotine.
FIG. 6 shows the inhibition of MAO A and MAO B for nornicotine.
FIG. 7 shows a plot of MAO inhibition versus time for Yerbamaté.
FIG. 8 shows the inhibition of MAO A and MAO B for Yerbamaté.
FIG. 9 shows a plot of MAO inhibition versus time for tobacco extract.
FIG. 10 shows the inhibition of MAO A and MAO B for tobacco extract.
FIG. 11 shows a plot of MAO inhibition versus time for GUMSMOKE.
FIG. 12 shows a plot of MAO inhibition versus time for a lozenge extract.
DETAILED DESCRIPTION OF THE INVENTION
MAO is an important enzyme that plays a major role in the metabolic transformation of catecholamines and serotonin. Neurotransmitters from this group are metabolized by MAO, and thus their effect is decreased at their receptor cites. MAO is important for the regulation of the levels of dopamine, norepinephrine and serotonin.
Accordingly, inhibition of this major enzyme system will have major effects on the functions regulated by this compound.
In a first embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of anabasine, anatabine or nornicotine to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
Anabasine, anatabine and nornicotine are minor tobacco alkaloids. These compounds are commercially available. However, they may be synthesized according to known techniques or extracted directly from tobacco itself.
Preferably, anatabine is synthesized according to the method disclosed by N. M. Deo and P. A. Crooks, “Regioselective Alkylation of N-(diphenylmethylidine)-3-(aminomethylpyridine: A Simple Route to Minor Tobacco Alkaloids and Related Compounds,” 1137-1141 (11 Dec. 1995), which is incorporated herein by reference.
In addition, nornicotine is preferably synthesized according to the method disclosed by S. Brandange and L. Lindblom, “N-Vinyl as N-H Protecting Group: A Convenient Synthesis of Myosmine,” Acta Chem. Scand., B30, No. 1, p. 93 (1976), which is also incorporated herein by reference.
In a second embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of Yerbamaté ( Ilex paraguariensis ) tea plant to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
The Yerbamaté extract may be prepared by shredding the Yerbamaté materials, mixing the shredded materials with a water/ethanol (for example, 1/1 by volume) solution in a mixture of about four leaves per 10 ml of the water/ethanol mixture, extracting with continuous stirring, and then removing the solution from the Yerbamaté residue. The residue can then be further extracted two more times with the same volume of water/ethanol mixture, and then the extracts may be combined and filtered to remove the particulate Yerbamaté materials. The combined extracts may then be subject to vacuum evaporation to yield the Yerbamaté extract.
In a third embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of a tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
The tobacco extract may be prepared by shredding tobacco leaves (for example, processed tobacco obtained from STAR TOBACCO, INC.), mixing the shredded leaves with a water/ethanol (for example, 1/1 by volume) solution in a mixture of about four leaves per 10 ml of the water/ethanol mixture, extracting with continuous stirring, and then removing the solution from the tobacco residue. The residue can then be further extracted two more times with the same volume of water/ethanol mixture, and then the extracts may be combined and filtered to remove the particulate tobacco leaf material. The combined extracts may then be subject to vacuum evaporation to yield the tobacco extract.
In a fourth embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of chewing gum and lozenges formulated with tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
The chewing gum and lozenges extract may be prepared by extracting five slices of GUMSMOKE chewing gum and NICOMINT lozenges (obtained from STAR TOBACCO, INC.), which are formulated with tobacco extract, with distilled water (50 ml) at room temperature for 12 hours, and then removing the undissolved gum substance by filtration.
The above compounds and substances were evaluated for their MAO inhibiting activity. Test results surprisingly showed that the compounds and substances of the present invention all provided MAO inhibition. It was also discovered that the MAO inhibiting effects had a different character than for known MAO inhibitors in that they reached an asymptotic or ceiling effect, so that further increases in the dose beyond maximal inhibition did not produce any further increase in the MAO inhibition. This asymptotic effect would provide many benefits. For example, the problems associated with previously known, irreversible MAO inhibitors, such as hypertensive effects, can be avoided. Furthermore, the inventive MAO inhibitors may be provided as an “over the counter” drug or dietary supplement in view of its safety and efficacy.
The MAO inhibitors of the present invention may be provided in forms well known to one skilled in the art. They may be formulated in a pharmaceutically acceptable carrier, diluent or vehicle and administered in effective amounts. They may be provided in the form of a capsule, pill, tablets, lozenge, gum, troches, suppositories, powder packets or the like.
The determination of the effective amounts for a given treatment can be accomplished by routine experimentation and is also well within the ordinary skill in the art.
EXAMPLES
To determine the effectiveness of compounds and substances of the present invention, experiments were conducted as follows:
MAO Reaction:
The MAO activities of the compounds and substances were determined using standard reaction conditions as described in Halt, A., et al., Analytical Biochemistry, 244:384-392 (1997).
Tissue Preparation:
Liver samples from cow or rat were obtained immediately after sacrifice. Liver was homogenized in a Polytron mechanical homogenizer in a ratio of 1 gram of liver to 1 ml of potassium phosphate buffer (0.2 M at pH of 7.6). Large membranes were removed by low speed centrifugation at 1000×g for 15 minutes. The supernatant was removed from the pellet and used immediately for MAO activity assays or stored at 0 degrees Centigrade. Protein levels were determined in the liver homogenate by the Bradford protein reaction.
Reaction Conditions:
The standard reaction conditions were developed as a modification of the spectrophotometric assay using standard conditions (Halt, A., et al., Analytical Biochemistry, 244:384-392 (1997)). Total MAO activity was determined by incubating the liver preparations for 30 minutes at 37 degrees Centigrade with a 1/1 dilution of a test fraction (compound or substance to be tested dissolved in distilled water) or control condition (water alone). This incubation allowed the test compound or substance to interact with the enzyme under physiological conditions. The final tissue concentration in the reaction mixture was 3.5 mg per 100 ml.
Following the incubation with test compounds/substances or control, the MAO reactions were initiated and the reactions were incubated at 37 degrees Centigrade. The reaction was initiated by mixing 150 μl of preincubated tissue with 150 μl of chromogenic solution (containing 10 mM vanillic acid, 5 mM 4-amino antipyrene, 20 units/ml of peroxidase in 0.2 M potassium phosphate buffer final concentration pH 7.6), 600 μl of amine substrate (tyramine 500 micromolar), and 100 μl of distilled water (1 ml reaction volume). The standard reaction time was for 1 hour, but reaction times varied from 1 minute to 3 hours to evaluate the time course of the reaction in the presence or absence of test substance or control. The reactions were terminated by the addition of 30 μl of a stop solution of phenelzine (10 mM). The stopped reactions were stored on ice and placed at room temperature for reading in a spectrophotometer at a wavelength of 498 nm. The resulting values were analyzed to determine the amount of reaction product produced by MAO activity. This assay was reliable and simple to perform. A standard curve using hydrogen peroxide for enzyme activity was prepared for each experiment to determine the activity of the enzyme.
Selective assays of MAO A and MAO B isoforms were determined by using selective inhibitors of each of these enzymes. During the preincubation of the enzyme with the test solutions, either pargyline or chlorgyline (final drug concentrations in the reaction mixture of 500 AM) was added to the reaction mixture. This technique allowed for the assay of MAO A or MAO B activity in the absence of the activity of the other isoform of the enzyme. All other reaction conditions were conducted as for total MAO activity studies.
Each of the compounds and substances of the present invention were evaluated by initially determining a concentration curve at a reaction time of one hour. After determining the concentration curves of each compound or substance on MAO activity, a reaction time course in the presence or absence of test compound or substance was determined and time course curves were generated. Following these experiments, the effect of each test compound or substance was evaluated on MAO A and MAO B activity by the same reaction studies as described above for the total enzyme activity.
Example 1
Anabasine, in its purified form, was dissolved in distilled water in a maximal inhibition concentration of 0.2 mg/ml, and tested according to the procedure described above. At maximal or saturating inhibition concentrations, anabasine was effective at inhibiting MAO activity by approximately 10-13%, and was effective at inhibiting the enzyme at all time points in the reaction.
FIG. 1 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of anabasine over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 5 determinations. All the data points shown in FIG. 1 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.01), and were representative of multiple experiments.
Since anabasine was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Anabasine was found to inhibit both MAO A and MAO B activity as shown in FIG. 2 . FIG. 2 presents the means (plus or minus the standard errors of the means) for 5 determinations for the percent inhibition of MAO A and MAO B activity. The effects of anabasine on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.05). The results demonstrate that anabasine inhibits both MAO A and B forms of the enzyme.
Example 2
Anatabine in its purified form, was dissolved in distilled water in a maximal inhibition concentration of 0.1 mg/ml, and tested according to the procedure described above. At maximal or saturating inhibition concentrations, anatabine was effective at inhibiting MAO activity by approximately 60%. This result shows that anatabine may be much safer as a medication than standard MAO enzyme inhibitors. Anatabine was effective at inhibiting the enzyme at all time points in the reaction, and was equally effective in inhibiting both MAO A and MAO B activities.
FIG. 3 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of anatabine over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 6 determinations. Anatabine was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 60%, as discussed above. All the data points shown in FIG. 3 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.005) and were representative of multiple experiments.
Since anatabine was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Anatabine was found to inhibit both MAO A and MAO B activity as shown in FIG. 4 . FIG. 4 presents the means (plus or minus the standard errors of the means) for 6 determinations for the percent inhibition of MAO A and MAO B activity. The effects of anatabine on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.01). The results demonstrate that anatabine inhibits both MAO A and -B forms of the enzyme.
Example 3
Nornicotine in its purified form, was dissolved in distilled water in a maximal inhibition concentration of 0.08 mg/ml, and tested according to the procedure described above. At maximal or saturating inhibition concentrations, nornicotine was effective at inhibiting MAO activity by approximately 80 to 95%, and was effective at inhibiting the enzyme at all time points in the reaction. Nornicotine was also equally effective in inhibiting both MAO A and MAO B activities.
FIG. 5 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of nornicotine over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 6 determinations. Nornicotine was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 80-95%, as discussed above. All the data points shown in FIG. 5 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.01) and were representative of multiple experiments.
Since nornicotine was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Nornicotine was found to inhibit both MAO A and MAO B activity as shown in FIG. 6 . FIG. 6 presents the means (plus or minus the standard errors of the means) for 6 determinations for the percent inhibition of MAO A and MAO B activity.
The effects of nornicotine on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.01). The results demonstrate that nornicotine inhibits both MAO A and B forms of the enzyme.
Example 4
The Yerbamaté extract was prepared as follows: Yerbamaté materials (obtained from STAR TOBACCO, INC.) were shredded and mixed with a water/ethanol (1/1 by volume) solution in a mixture of about four leaves per 10 ml of the water/ethanol mixture; the materials were then extracted overnight with continuous stirring; the solution was then removed from the Yerbamaté residue and stored; the residue was then further extracted overnight two more times with the same volume of water/ethanol mixture, and the three extracts were combined and filtered to remove the particulate Yerbamaté material; and the combined extracts were subjected to removal of the water/ethanol by vacuum evaporation. The resultant extract was then weighed and solubilized in distilled water.
When tested, Yerbamaté extract was effective in inhibiting MAO activity. The maximal inhibition concentration was 10 mg/ml. At maximal or saturating inhibition concentrations, the Yerbamaté extract inhibited MAO activity by approximately 40 to 50%. The results suggest that Yerbamaté may be much safer as a medication than standard MAO enzyme inhibitors. The extract was effective in inhibiting MAO at all time points in the reaction, and was equally effective in inhibiting both MAO A and MAO B activities.
FIG. 7 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of Yerbamaté over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 5 determinations. Yerbamaté was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 40-50%, as discussed above. All the data points shown in FIG. 7 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.005) and were representative of multiple experiments.
Since Yerbamaté was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above: Yerbamaté was found to inhibit both MAO A and MAO B activity as shown in FIG. 8 . FIG. 8 presents the means (plus or minus the standard errors of the means) for 5 determinations for the percent inhibition of MAO A and MAO B activity.
The effects of Yerbamaté on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.01). The results demonstrate that Yerbamaté inhibits both MAO A and B forms of the enzyme.
Example 5
The tobacco extract was prepared in the same manner as in Example 4, except that processed tobacco leaves (obtained from STAR TOBACCO, INC.) were substituted for the Yerbamaté materials.
When tested, the tobacco extract was effective in inhibiting MAO activity. At maximal or saturating inhibition concentrations, the tobacco extract was able to inhibit MAO activity by approximately 60%. The results suggest that the extract may be much safer as a medication than standard MAO enzyme inhibitors. The tobacco extract was effective at inhibiting MAO at all time points in the reaction, and was equally effective in inhibiting both MAO A and MAO B activities.
FIG. 9 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of tobacco extract over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 8 determinations. Tobacco extract was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 60%, as described above. All the data points shown in FIG. 9 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.001) and were representative of multiple experiments.
Since tobacco extract was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Tobacco extract was found to inhibit both MAO A and MAO B activity as shown in FIG. 10 . FIG. 10 presents the means (plus or minus the standard errors of the means) for 8 determinations for the percent inhibition of MAO A and MAO B activity. The effects of tobacco extract on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.005). The results demonstrate that tobacco extract inhibits both MAO A and B forms of the enzyme.
Examples 6 and 7
The extract of GUMSMOKE chewing gum or lozenges was prepared as follows: five slices each of gum or lozenges, formulated with tobacco extract, were extracted with 50 ml of distilled water at room temperature for 12 hours. The undissolved gum substance was removed by filtration. (The lozenges dissolved completely.) Dilutions of these extracts were prepared for evaluation.
The gum and lozenges extracts were effective in inhibiting MAO activity. At maximal or saturating concentrations, the extracts were able to inhibit MAO activity by approximately 50 to 60%.
FIG. 11 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of an extract of GUMSMOKE chewing gum prepared as described above over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 4 determinations. GUMSMOKE extract was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 50-60%. All the data points shown in FIG. 11 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.05) and were representative of multiple experiments.
FIG. 12 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of an extract of the lozenge prepared as described above over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 4 determinations.
The lozenge extract was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 50-60%. All the data points shown in FIG. 12 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.05) and were representative of multiple experiments. Both MAO A and MAO B were also inhibited by these extracts. | The present invention provides a group of tobacco alkaloids, tobacco extract, Yerbamaté extract, and an extract of chewing gum and lozenges which are modulators of monoamine oxidase (MAO) activity (i.e., compounds and substances which inhibit MAO enzyme and prevent its biological activity). The MAO inhibitors of the present invention can cause an increase in the level of norepinephrine, dopamine, and serotonin in the brain and other tissues, and thus can cause a wide variety of pharmacological effects mediated by their effects on these compounds. The MAO inhibitors of the present invention are useful for a variety of therapeutic applications, such as the treatment of depression, disorders of attention and focus, mood and emotional disorders, Parkinson's disease, extrapyramidal disorders, hypertension, substance abuse, smoking substitution, anti-depression therapy, eating disorders, withdrawal syndromes, and the cessation of smoking. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] (Not applicable)
REFERENCE TO SEQUENTIAL LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON A COMPACT DISC
[0002] (Not applicable)
BACKGROUND OF THE INVENTION
[0003] 1) Field of the Invention
[0004] This invention relates to rakes for gathering leaves or other debris. Also, this invention is directed to implements for cleaning floors, such as push brooms, for cleaning dirt and other debris from floors.
[0005] 2) Description of the Related Art
[0006] Raking leaves is often arduous and time-consuming labor. Heretofore, devices have been developed for reducing the laborious task of hand raking by providing wheeled raking devices.
[0007] Power raking machines which utilize a gas or electric motor to drive a reciprocating rake head are shown in U.S. Pat. Nos. 3,777,460 and 3,417,554. These machines are often used for general lawn conditioning purposes such as removing thatch or dead grass from lawns. They require access to an external electrical hookup as well as extended lengths of electrical extension cord. The resulting machines are rather heavy and inconvenient to use for raking loose lawn cover such as leaves. Power machines do not appear to be practical for such purposes.
[0008] Manual raking devices have been developed, such as shown in U.S. Pat. Nos. 2,329,708 and 1,020,228, wherein raking tines are supported by wheels. The devices may be rolled along the ground with the raking tines gathering leaves and the like in the path of the device. Such devices do not require an auxiliary power source. However, the raking tines are only moved over the ground and are not provided with a simulated raking action. Leaves can soon accumulate beneath the raking tines resulting in a dragging raking action which will not rake cleanly.
[0009] In U.S. Pat. No. 3,824,773, a wheeled power raking device is disclosed having a plurality of individual hand rakes operated by a crankshaft. The crankshaft is powered by an electric motor to move the individual rakes through a raking motion over the ground. Again, the attendant inconveniences and dangers of having an auxiliary power source are necessary and appear to outweigh the practical advantages of such a device, except possibly for commercial application.
[0010] The process of using rakes which do not have the above labor-saving additions varies depending on the type of landscape to be cleared. In the raking process in open areas, the user stands upright, lifts the rake, extends it forward and places it on the ground having debris. The user then retracts the rake, pulling back the debris. This sequence is repeated until the ground has been cleared of debris.
[0011] In the raking process under low-imbed trees and shrubs, the user bends over and grips the rake so that the rake may be extended off the ground in a low trajectory. The rake is then extended under the limbs before placing it on the ground having debris. The rake is then retracted, pulling the debris with it.
[0012] As can readily be appreciated, in spite of the improvements which have been made, raking is still an arduous process. The wheeled rakes are heavy and are not easily turned. The conventional rakes require lifting each time the rake is moved.
[0013] Implements for cleaning floors are well known. Such implements are brooms, mops, and squeegees. Common push brooms contain bristles of horsehair, fiberglass, or plastic. These bristles are fastened into generally rectangular bases made of wood or plastic. The bases have two attachment holes for the handles. These holes are placed at complementary angles to allow for even wear of the bristles. Commonly, the holes and the handles are threaded for easy attachment and disengagement. Some type of stabilizing reinforcement mechanism is common in push brooms. A typical prior art push broom is found in U.S. Pat. No. 4,384,383, granted to Bryant May 24, 1983.
[0014] The prior art push brooms may be used with a pushing motion to push dirt and other debris away from the user or may be operated with a pulling motion to bring dirt and other debris toward the user. Either mode of use requires the broom to be lifted at the end of one cleaning movement and placed in a new desired position for the next cleaning movement.
BRIEF SUMMARY OF THE INVENTION
[0015] The present invention addresses the problems outlined above and seeks to eliminate them while still maintaining a rake which will clear debris or an implement for cleaning floors. The present invention is directed to a new rake or implement for cleaning floors which allows the user to remain upright under all conditions and which eliminates the step of lifting the rake or implement for cleaning floors each time it is used. The rake or implement for cleaning floors of this invention has a unique handle which allows the user to remain erect while raking or cleaning floors. The handle also allows for easy storage and has a unique handgrip which allows for easy transportL
[0016] The rake of one embodiment of the present invention has a bulb-shaped front end joining sloping shoulders for penetration into hard-to-reach areas. This shape increases the debris-contaiunment width and overall containment area. The rake of a second embodiment contains a rake head featuring a single smooth arc. The rake head of a third embodiment features a rake head having a straight frame. The rake head has sidepieces which glide along the ground. The sidepieces may have bottoms which are so shaped to glide along the ground or which fit into skis or spoons which glide along the ground to enable the user to avoid lifting the rake each time the rake is used. The rake of the invention may also have an adjustable handle.
[0017] The floor cleaning implement of this invention contains a handle similar to that used with the rake. The preferred embodiment of such an implement is a push broom. The broom base contains conventional bristles, a connection for the handle, and connections for the wheel mechanism. The wheel mechanism may be mounted on either side of the broom base so as to permit even wear of the bristles. The wheel mechanism supports either fixed or swivel wheels so as to allow the broom to be moved to a desired new position without lifting the broom.
[0018] As can be readily seen from the above, this invention allows for the accomplishment of the laborious tasks of raking and cleaning floors without the usual steps of lifting and carrying the rake or implement for cleaning floors and setting the rake or implement for cleaning floors in a new position.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0019] FIG. 1 is a side elevational view of the rake of this invention in the lowered, or operating, position.
[0020] FIG. 2 is a side elevational view of the rake of this invention in the raised, or moving, position
[0021] FIG. 3 is a side elevational perspective view of the rake head of one embodiment of this invention.
[0022] FIG. 4 is a side elevational perspective view of the rake head of a second, and preferred, embodiment of this invention.
[0023] FIG. 5 is a front elevational perspective view of the rake head of FIG. 4 .
[0024] FIG. 6 is a plan view of the rake head of FIG. 4 .
[0025] FIG. 7 is a rear sectional view of the rake head of this invention at the point where the handle attaches to the crossbar.
[0026] FIG. 8 is a front elevational view of the rake head according to a third embodiment of this invention
[0027] FIG. 9 is a side elevational view of the rake head of the third embodiment of third invention.
[0028] FIG. 10 is a plan view of the rake head of the third embodiment.
[0029] FIG. 11 is a sectional view of a portion of the crossbar showing attachment of the handle to the crossbar.
[0030] FIG. 12 shows one alternative of transporting the rake of this invention.
[0031] FIG. 13 shows a second alternative of transporting the rake of this invention.
[0032] FIG. 14 is a front elevational perspective view showing the mechanism which allows for lengthening and shortening of the handle.
[0033] FIG. 15 is a plan view of the rake head and a portion of the handle showing a handgrip on the distal end of the handle.
[0034] FIG. 16 is a front view of the handgrip located at the proximal end of the handle.
[0035] FIG. 17 is a side view of the handgrip of FIG. 16 .
[0036] FIG. 18 is an elevational side view of several alternatives for designs of the side-piece and glide of the rake of this invention.
[0037] FIG. 19 is a side elevational view showing the rake hung on a wall using a conventional implement hanger.
[0038] FIG. 20 is a side elevational view showing the rake hung on a wall using a nail.
[0039] FIG. 21 is a horizontal cross-sectional view of a type of implement hanger which may be used to hang the rake or broom of this invention.
[0040] FIG. 22 is a side elevational view of the broom of this invention.
[0041] FIG. 23 is a plan view of the broom head.
[0042] FIG. 24 is an exploded elevational perspective view showing the handle holder, adapter, and the distal portion of the handle.
[0043] FIG. 25 is a side elevational view of the broom head showing the wheel plate holder and the handle adapter.
[0044] FIG. 26 is an elevational perspective view of the wheel plate holder.
[0045] FIG. 27 is a side elevational view of the pin assembly for the wheel plate holder.
[0046] FIG. 28 is a front elevational view of the pin assembly for the wheel plate holder.
[0047] FIG. 29 is a plan view of the front portion of a wheel plate inserted in a wheel plate holder.
[0048] FIG. 30 is a plan view of the front portion of a wheel plate.
[0049] FIG. 31 is a side elevational view of a wheel attached to a wheel plate.
[0050] FIG. 32 is a side elevational view, partly in cut-away, of a swivel wheel attached to a wheel plate.
DETAILED DESCRIPTION OF THE INVENTION
[0051] The rake 2 of the present invention presents several improvements not known to the prior art, each improvement designed to make the task of raking easier to the user. The rake 2 , broadly, is shown in FIGS. 1 and 2 . The rake 2 has a proximal handgrip 4 at the proximal end 6 which is attached to, and almost completely covers, the first, upwardly slanted, section 8 of the handle 10 . The first section 8 of the handle 10 is bent to form a second, horizontal, section 12 . The second section 12 is bent to become a steep downwardly slanted third section 14 . The third section 14 is bent upward to form a fourth, straight, gradually downwardly slanted, section 16 of the handle 10 . The fourth section 16 attaches at its distal end 18 to the rake head 20 .
[0052] With reference to FIGS. 3-7 and 18 , the rake head 20 will be described. A rear crossbar 22 having two ends 24 is attached at each end 24 to a sidepiece 26 of the rake head 20 . The sidepiece 26 may be no more than a frame but preferably it is substantially solid, as see FIG. 18 . The sidepiece 26 may be rounded on the bottom 28 and cause the rake 2 to glide when it is pulled along the ground or, preferably, it fits into a glide ski 30 or a glide spoon 32 with the same effect. Reference is made once more to FIG. 18 for the various alternatives. When a glide ski 30 or glide spoon 32 is used, the glide ski 30 or glide spoon 32 is preferably welded to the sidepiece 26 although other forms of attachment, such as bolting, are acceptable.
[0053] In one embodiment as shown in FIG. 3 , the frame 34 extends from the forward end 36 of each sidepiece 26 in a single arc meeting at the center 38 which is the forward extension of the frame 34 . Extending downwardly from the frame 34 are the tines 40 . The tines 40 may be the same as or similar to tines of conventional rakes. They are spaced apart the same distance as in conventional rakes. However, since the angle at which the tines 40 contact the debris is different from the angle in a conventional rake, the apparent spacing between the tines 40 is decreased and there is greater contact of the tines 40 with the debris as compared to conventional rakes. It is intended that the present rake 2 be substantially wider than rakes of the prior art. This greater width, coupled with the presence of the side pieces 26 , allows the rake 2 of the present invention to transfer a substantially greater amount of debris.
[0054] In a second, and preferred, embodiment as shown in FIGS. 4-7 , the frame 34 extends from the forward end 36 of each sidepiece 26 in a gradual arc 42 . About halfway to the center 38 , the slope of the arc 42 becomes steeper 44 and changes again to become more gradual 46 near the center 38 so that the frame 34 reaches its greatest protrusion at the center 38 of the frame 34 . Using this configuration, the rake 2 is able to contact the ground farther under shrubbery than can conventional rakes. As with the first embodiment, the tines 40 extend downwardly from the frame 34 and may be the same as or similar to tines 40 of conventional rakes. They are spaced apart the same distance as in conventional rakes. However, since the angle at which the tines 40 contact the debris is different from the angle in a conventional rake, the apparent spacing between the tines 40 is decreased and there is greater contact of the tines 40 with the debris as compared to conventional rakes.
[0055] The crossbar 22 contains a central notch 48 which holds the handle 10 . The distal end 18 of the handle 10 attaches to the center 38 of the frame 34 . This notch 48 helps to stabilize the handle 10 .
[0056] A third embodiment is disclosed in FIGS. 8-11 . The rake head 20 is made up of a straight frame 34 which extends from one side to the other as in conventional rakes. On each side, a sidepiece 26 extends rearwardly from the frame 34 . A crossbar 22 extends from one sidepiece 26 to the other behind the frame 34 . The crossbar 22 contains a notch 48 in the center for supporting the distal end 18 of the handle 10 prior to its attachment to the frame 34 . The bottom 28 of the sidepiece 26 may be rounded or a glide ski or glide spoon 32 may attached to the bottom 28 of the sidepieces 26 . As in the above embodiments, a downward pressure on the handle 10 tilts the rake head 20 upwardly allowing the rake 2 to be repositioned without lifting.
[0057] As can be readily appreciated, in use the head 20 of the rake 2 is placed on the ground in the desired position, retracted toward the user, slid forward and to the side to another desired position, and retracted again. This operation does not involve lifting the rake head 20 off of the ground to change its position.
[0058] The handle 10 may be lengthened or shortened by using a connecting sleeve 50 as shown in FIG. 14 . The connecting sleeve 50 is a clamp which fits around the proximal 52 and distal 54 sections of two adjacent sections of the handle 10 . It may be fixedly attached to either section and moveably attached to the other section. For purposes of illustration, when the connecting sleeve 50 is fixedly attached to the proximal section 52 , the distal section 54 may be moved proximally or distally and when the distal section 54 is in the desired position, the connecting sleeve 50 may be tightened. The connecting sleeve 50 contains two bolts 62 and two nuts for use in the wing portions 64 of the connecting sleeve 50 or two bolts 62 and threaded wing portions 64 .
[0059] The center of gravity of the rake 2 of the present invention is immediately proximal to the rear of the head 20 . Thus it may be easily carried as shown in FIG. 12 by holding it at that place or it may be easily dragged along the ground as shown in FIG. 13 . For holding the rake 2 , a distal handgrip 66 as shown in FIG. 15 is provided.
[0060] The rake 2 of the present invention may be easily stored by virtue of a proximal handgrip 4 . As seen in FIGS. 16 and 17 , the handle 10 contains a hole 68 in the proximal handgrip 4 so that the hole 68 may be placed over a nail driven into the wall. When this is done the rake 2 fits close to the wall and the tines 40 are pointed toward the wall as shown in FIG. 20 .
[0061] Alternatively, a common implement holder 70 , such as a Crawford broom clip, as shown in FIG. 21 may be mounted on a wall and the rake 2 may be fitted into it at the bend between the third 14 and fourth 16 sections of the handle 10 as shown in FIG. 19 .
[0062] The implement for cleaning floors will now be discussed with reference to a push broom 72 . The broom 72 of the present invention is viewed in FIG. 22 . The broom handle 74 has a handgrip 4 at the proximal end 6 which is attached to, and almost completely covers, the first, upwardly slanted, section 8 of the handle 74 . The first section 8 of the handle 74 is bent to form a second, horizontal, section 12 . The second section 12 is bent to become a steep downwardly slanted third section 14 . The third section 14 is bent upwardly to form a fourth, straight, gradually downwardly slanted, section 16 of the handle 74 . The fourth section 16 attaches at its distal end 76 to an adapter 78 which is connected to the rectangular base 80 of the broom 72 .
[0063] With reference to FIG. 23 , it is seen that two wheel plate holders 82 are mounted on the top surface 84 of the broom base 80 . The two wheel plate holders 82 are equidistant from the side ends 86 of the broom base 80 . The handle holder 88 (not shown in FIG. 23 ) is located at the center of the top surface 84 of the broom base 80 .
[0064] With reference to FIGS. 26-29 , the wheel plate holder 82 is made up of a bottom piece 90 , two side pieces 92 and a top piece 94 . The bottom piece 90 has a plurality of connector holes 96 at each end 98 thereof for connecting to the top surface 84 of the base 80 with screws or bolts. The bottom piece 90 also contains a plurality of locking holes 100 located along the center line of the bottom piece 90 for holding the locking pins 102 . The side pieces 92 extend upwardly from the bottom piece 90 medially from the connector holes 96 . The side pieces 92 are of such a height as to allow easy, but snug, entrance of the wheel plate 104 . The top piece 94 bridges the two side pieces 92 and contains a plurality of holes 106 equidistant from the side pieces. Thus, in use, the wheel plate holder 82 is an open slot firmly affixed to the top surface 84 of the broom base 80 and is of such size as to allow the snug fit of the wheel plate 104 .
[0065] A pin holder 108 fits on the top piece 94 of the wheel plate holder 82 and holds a plurality, preferably two, locking pins 102 . The locking pins 102 pass through the top piece 94 of the wheel plate holder 82 and the wheel plate 104 and into the bottom piece 90 of the wheel plate holder 82 . As an option, the locking pins 102 may pass through the bottom piece 90 and into the broom base 80 . As another, but less desired, alternative, the locking pins 102 may be presented without the pin holder 108 . This alternative is just as effective, but allows for the loss of loose pins 102 .
[0066] The wheel plate 104 , as seen in FIGS. 30-32 , has a free front end 110 and a free rear end 112 . The free front end 110 contains holes 114 which are complimentary to the holes 100 , 106 in the top 94 and bottom piece 90 of the wheel plate holder 82 . Thus the wheel plate 104 may be firmly held in place by the locking pins 102 . The wheel plate 104 may be used on either side of the broom base 80 , thus permitting even wear of the bristles 116 .
[0067] The free rear 112 end of the wheel plate 104 may be a swivel wheel shown in FIG. 32 which comprises ball bearings 118 , a wheel holder 120 , an axle 122 , and a wheel 124 . the ball bearings 118 allow free movement between the wheel plate 104 and the wheel holder 120 . The broom 72 preferably features fixed wheel holders 120 shown in FIG. 31 . By use of the wheel plate holder 82 , the wheel plate 104 , and the wheel 124 , the operator may apply downward pressure on the broom handle 74 and the broom base 80 is lifted free from the surface being cleaned. This allows the rolling of the broom 72 to a new position for a new cleaning operation and avoids the lifting step common to prior art brooms.
[0068] With reference to FIG. 24 , the connection of the broom handle 74 to the broom base 80 will be described. The broom handle holder 88 is situated at the center of the top surface 84 of the broom base 80 . The broom handle holder 88 is made up of a bottom piece 126 , two side pieces 128 and a top piece 130 . The bottom piece 126 has at least one connector hole (not shown) at each end thereof for connecting to the top surface 84 of the broom base 80 with screws or bolts. The bottom piece 126 also contains at least one locking hole 132 located along the center line of the bottom piece 126 for holding the locking pin(s) 134 . The side pieces 128 extend upwardly from the bottom piece 126 medially from the connector holes. The side pieces 128 are of such a height as to allow easy, but snug, entrance of the handle connector plate 136 . The top piece 130 bridges the two side pieces 128 and contains at least one hole 138 equidistant from the side pieces 128 . Thus, in use, the handle holder 88 is an open slot firmly affixed to the top surface 84 of the broom base 80 and is of such size as to allow the snug fit of the handle connector plate 136 .
[0069] A locking pin 134 fits on top of the handle holder 88 and passes through the top piece 130 of the handle holder 88 and the handle connector plate 136 and into the bottom piece 126 of the broom handle holder 88 . As an option, the locking pin 134 may pass through the bottom piece 126 and into the broom base 80 .
[0070] The handle connector plate 136 , like the wheel plate 104 , fits into either side of the broom base 80 , allowing for even wear of the bristles 116 . The proximal end of the handle connector plate 136 contains an upward angle and is attached to an adapter 78 . The adapter 78 is preferably solid, but may be hollow. The adapter 78 contains a screw hole 140 in its upper surface 142 . The hollow handle 74 fits over the top of the adapter 78 and fastens thereto with a screw passing through the screw hole 144 on the handle 74 and the screw hole 140 in the adapter 78 . The features of the preferred broom handle 74 are like those described for the preferred handle 10 of the above-described rake 2 .
[0071] Although the invention has been described and illustrated in detail, it is to be clearly understood that the same is by way of illustration and example, and is not to be taken by way of limitation. The spirit and scope of the present invention are to be limited only by the terms of the appended claims. | A rake having a curved handle and a rake head which is made up of a frame having a crossbar connecting the sides of the frame and connecting to the handle. The rake head contains sidepieces which are so shaped as to enable the rake head to glide across the ground. The sidepieces may fit into ski glides or spoon glides to provide this property. The frame is straight or is arced so as to provide a large area of containment. The invention also presents a broom or squeegee having the same handle as the rake. The handle is connected to an adapter, which fits into either side of a handle connector. The broom or squeegee is also connected to wheels so that it may be moved without being lifted from the surface to be cleaned or dried. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention finds one particular application in connecting a flat bundle of optical fibers to an integrated optical device.
2. Description of the Prior Art
One method for making such connections that is known in itself uses a flat bundle of planar waveguides formed for this purpose in layers of doped silica deposited onto a silicon substrate. At the same time housings are hollowed into the substrate with surfaces that follow crystal planes of the substrate and therefore enable accurate location of the optical fibers to couple them to the respective planar waveguides. This method that is known in itself is described in more detail in the remainder of the present description. It has the disadvantage that it does not produce good optical coupling between planar waveguides and the optical fibers when it is required to deposit the layers of silica by a relatively low cost method of deposition that is known in itself. The present invention is a result of discovering the causes of this drawback and consequently provides a remedy to this drawback. Nevertheless, it seems that these causes can give rise to similar disadvantages in other circumstances and that the same remedy can then be used with advantage. This is why the invention is first described hereinafter in a more general manner and then in one particular application.
SUMMARY OF THE INVENTION
Firstly, the invention consists in a method of fabricating a component having a crystalline silicon substrate, the method including the steps of:
depositing a layer of silica onto a crystalline silicon substrate, this silica layer being doped with dopants,
eliminating said doped silica layer over a region to be treated of said substrate, and
treating said substrate in said region to be treated so that the quality of the fabricated component is conditioned by the quality of the crystal lattice of said substrate in said region. This treatment can be of various kinds, as explained hereinafter. Regardless of the nature of the treatment, before the deposition of said layer of doped silica, the method includes a step of forming on said substrate a barrier layer of a barrier material opposing diffusion of said dopants, said doped silica layer being deposited onto said barrier layer at a high temperature such as that of flame hydrolysis, said barrier layer being eliminated in said region to be treated before said treatment step.
The barrier material is preferably a silica containing none of said dopants, at least those of the dopants of the doped silica layer that could degrade the useful qualities of the substrate. This silica is typically pure silica. The barrier layer is then advantageously formed by oxidation of the substrate. This layer can be made 400 nm thick by exposing the substrate to an oxygen atmosphere at 1350° C. for 1 h, for example. However, this layer could equally well be formed by the flame hydrolysis deposition (FHD) process or by the plasma enhanced chemical vapor deposition (PECVD) process. At least one other barrier material may be used: silicon nitride.
This invention finds typical applications in the fabrication of optical and electro-optical components, the doped silica being used to guide light waves, the crystalline silicon being used for its optical, electrical, thermal conduction or ease of etching properties. The invention is in particular a result of the fact that it has been found that the crystal lattice of the silicon can be gravely disrupted by the diffusion of dopants which, in methods of fabricating optical components that are known in themselves, are included in a layer of silica deposited onto a silicon substrate. It is also a result of the fact that the rates of diffusion of such dopants are much lower in the barrier materials proposed than in silicon, for example one hundred times lower in the case of silica. These rates increase with temperature and, for the usual dopants, they become high only above 1000° C. The present invention therefore finds applications when the substrate carrying the layer of doped silica must or can be heated to a high temperature at a time when treatment that necessitates good crystalline qualities of the substrate has not yet been carried out.
The invention will be usefully employed in certain industrial processes in which a step of treatment of this kind of a crystalline silicon substrate is prevented or merely rendered ineffective, difficult or costly when the substrate has been covered with a layer of doped silica. These processes are those in which the temperature reached during deposition of the doped silica causes diffusion into the silicon of dopants from this layer and in which such diffusion in turn causes degradation of the qualities that it is intended to exploit. In this context, the important characteristics include:
the natures of said dopants and their required concentrations in the layer of doped silica, and
the foreseeable temperatures to which the substrate is exposed and the foreseeable time periods for which it is exposed to such temperatures, and
the nature and the methods of the treatment to be effected.
Insofar as the natures and the concentrations of the useful dopants are required, boron and phosphorus may be cited in concentrations in the order of one molar percent relative to the silica. The function of these dopants is to reduce the viscosity of the silica to enable its temperature of use to be reduced or to enable the refractive index of the silica to be modified, for example. This index is reduced by approximately 5×10 −4 for each molar percentage point in the case of boron or phosphorus.
Other dopants that can be used for other functions include germanium, titanium, fluorine, chlorine, nitrogen, etc.
Where the foreseeable temperatures are concerned, it may be mentioned that the present invention enables the layer of doped silica to be deposited by the FHD process. This process, which is known in itself, has the advantage of being relatively economical but the disadvantage of heating the substrate to a temperature of 1350° C. for one hour. A significant temperature rise could also be required if the FHD process were replaced with the PECVD process, for example.
Where the treatment to be effected on the substrate is concerned, a typical treatment is guided etching, said region to be treated then being a region to be etched. Etching of this kind is effected by exposing the substrate to an etchant that is “guided” in the sense that the silicon is preferentially etched by the etchant parallel to the crystal planes of the substrate, so that the etching is guided by these planes. The etching rate is then typically much higher parallel to these planes than perpendicular to them. This etching exposes one or more crystal planes to exploit the fact that these planes have precisely defined relative orientations.
Using this typical method, the barrier layer is formed on a plane surface oriented along a crystal plane of the substrate. After elimination of the layer of doped silica and of the barrier layer over at least the region to be etched of this plane face, the etching processing steps are as follows:
definition of a guided etchant adapted to etch the substrate in a manner guided by crystal planes of the substrate,
application to this region to be etched of a layer resistant to said guided etchant and having at least one definition edge oriented in a crystal direction of the substrate, and then
exposing said plane face to said guided etchant to expose at least one crystal plane of the substrate from said definition edge, this plane forming a non-zero dihedral angle with this face. There is typically formed in this way, between two crystal planes exposed in this way, a locating Vee enabling precise orientation of an optical fiber on a silicon substrate. Crystal planes exposed in this way could have other functions, however, for example they could constitute mirrors to reflect infrared light guided in a layer of silica formed on the substrate.
In the case of another kind of treatment to be effected on the substrate, electrically conductive tracks, for example gold tracks, are formed on the latter to energize an active component such as a laser attached to the substrate. The dielectric constant of the material of the substrate must then be homogeneous and predictable. It has been found that this constant is seriously and erratically modified by the presence of impurities disrupting the crystal lattice. Consideration may also be given to the use of the semiconductor properties of the crystalline silicon.
One embodiment of the present invention is described hereinafter with reference to the accompanying diagrammatic drawings. If an item appears in more than one figure, it is always designated by the same reference symbol. The photosensitive resins employed are not shown.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 through 7 show successive steps of the method of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The application described by way of example is a method of fabricating a planar waveguide to be connected to an optical fiber. A method for this known in itself and previously referred to includes the following steps that are also employed in the context of the invention:
Formation of a substrate 2 made up of crystalline silicon and having a top face 4 oriented in a crystal plane of the substrate, a crystal direction of the substrate being oriented in this crystal plane and constituting a longitudinal direction D, two longitudinally successive regions of this top face respectively constituting a guide region RG and a fiber region RF.
Deposition, on said top face 4 of a layer 6 of doped silica, said layer 6 , constituting a bottom confinement layer and including dopants which lower the refractive index of the silica. For example, this layer is 0.02 mm thick and the silica is doped with boron oxide in a molar concentration of 10% to give it a refractive index of 1.445 for transmitting light at a wavelength of 1300 nm.
Depositing, on said bottom confinement layer 6 of a doped silica, a core layer 8 made up of silica having a refractive index higher than that of said doped silica. For example, this layer is 0.007 mm thick and is made up of silica with a majority doping of germanium oxide in a molar concentration of 3%. It therefore has a refractive index of 1.450 for the light to be transmitted.
Deposition, onto said core layer 8 , a complete protective layer 10 . This layer is conventionally chromium.
Etching of said complete protective layer 10 so that the remaining parts of this layer constitute a limited protective layer including guide core protection strips 12 in said guide region RG and two housing definition strips 14 , 16 in said fiber region RF. Each core protection strip 12 has a longitudinal axis AG. The two housing definition strips 14 , 16 define between them a fiber housing strip having two longitudinal edges 18 constituting two housing definition edges and extending symmetrically on either side of an axis AF aligned with the axis of a guide core protection strip 12 . This etching of the chromium protective layer is effected by conventional photolithography, and likewise other subsequent etches, by depositing a photosensitive resin, exposing the resin through an exposure mask, developing the resin by selective washing to eliminate it according to whether it was exposed or not, and then etching with an etchant such that the remaining parts of the resin resist etching. The chromium layer is conventionally etched using a standard solution such as that sold by Shipley under the registered trademark “Chrome-etchant”.
The remaining photosensitive resin is not eliminated immediately. The resin used for this etching will be referred to hereinafter as the “first resin”.
Elimination of said core layer outside said limited protective layer. The silica etchant used is such that the first photosensitive resin still in place resists this etchant. The etching is limited to spare the bottom confinement layer under the core layer. For example, reactive ion etching is used assisted by a low-pressure plasma of a fluorinated gas such as CHF 3 or C 2 F 6 . The outcome of this etching is shown in FIG. 1 . This etching of the core layer 8 forms the core 20 of the future planar waveguide in the guide region, the core being visible in FIG. 2 .
After this etching the first resin and the protective layer 10 are removed completely.
Depositing an etching stop layer 22 of silicon 300 nm thick, for example.
Elimination of said etching stop layer in said guide region. This elimination is effected by photolithographic etching using a second photosensitive resin eliminated by development in the guide region. The outcome of this elimination step is shown in FIG. 2 .
Deposition of a layer of doped silica constituting a top confinement layer 24 including dopants reducing the refractive index of the silica. This layer is deposited in exactly the same way as the bottom confinement layer 6 . In the guide region, the guide core and the bottom and top confinement layers constitute the planar waveguide. The outcome is shown in FIG. 3 .
Etching of the top confinement layer to eliminate it in the fiber region. This is again a photolithographic process. It is effected by means of a third resin that development eliminates in the fiber region. The reactive ion etching (RIE) is stopped by the etching stop layer. The third resin is then completely eliminated, the outcome being shown in FIG. 4 .
Elimination of the etching stop layer by reactive ion etching assisted by a low-pressure plasma of sulfur hexafluoride SF 6 . This etching can instead be effected using a dilute solution of potassium hydroxide KOH applied for approximately one minute.
Deposition and growth of a fourth resin to protect the guide region.
Limited etching of the silica in the fiber region. The etchant used is anisotropic, i.e. the etching is effected in the vertical direction. The etching process is reactive ion etching, for example.
Etching is stopped when the silicon substrate is exposed in said housing strip. A silica layer 26 therefore remains in the housing definition strips. The outcome is shown in FIG. 5 .
Etching of the substrate by an etchant guided by crystal planes of the substrate. The purpose of this etching is to hollow out a housing 28 for an optical fiber in said housing strip, this housing having two flanks consisting of two respective crystal planes of the substrate. These planes pass through said two housing definition edges. The silica layer 26 remaining in the housing definition strips resists the guided etchant. The housing obtained typically has a truncated V-shape cross-section and constitutes a locating Vee as previously defined. The optical fiber that it locates is aligned with the planar waveguide in a horizontal plane by the fact that the exposure mask used in etching of the protective layer has defined two precisely aligned axes, one for the core protection strip and the other for the fiber housing strip. In the vertical direction, correct positioning of the fiber is obtained by virtue of an appropriate corresponding relationship between the thickness of the bottom confinement layer and the width of the fiber housing strip. Good coupling can therefore be obtained between the optical fiber positioned in this way and the planar waveguide. This etching of the substrate is conventionally carried out using an aqueous solution of potassium hydroxide at a concentration of 190 g per liter applied for 90 minutes at a temperature of 75° C. The outcome of this etching is shown in FIG. 6 .
Total elimination of the silica in the fiber region.
Finally, total elimination of the fourth resin, the outcome being shown in FIG. 7 .
In practise, a plurality of planar waveguides and a plurality of housings for a flat bundle of a plurality of optical fibers to be connected to the respective waveguides are formed simultaneously on the same top face of a substrate. Most of the housing delimiting strips are therefore common to two adjacent housings and located between the two housings.
The quality of the optical coupling obtained after use of the fabrication method that is known in itself which has just been described is not always good. It has been found that it depends on the deposition process used to form the silica layer, i.e. the two confinement layers and the core layer. Of the processes for effecting such deposition that are known in themselves, the plasma enhanced chemical vapor deposition (PECVD) process has the disadvantage that it is more costly to implement than the flame hydrolysis deposition (FHD) process. Nevertheless, the PECVD process has been preferred since experience has shown that the good optical coupling is obtained only if the PECVD process is used. In accordance with the present invention, it has been found that the optical coupling defects that experience had shown to exist after using the FHD process were related to the relatively high temperatures (1350° C.) involved in this process and to the dopants such as phosphorus and boron included in the bottom confinement layer. To be more specific, it has been found that these defects were the result of the fact that the dopants diffused so quickly into the silicon at high temperature that they seriously disrupted the crystal lattice of the silicon in the vicinity of the top face of the substrate. They then prevented the step of etching the substrate to expose the appropriate crystal plane.
One aim of the present invention is to make the use of the FHD silica deposition process compatible with good optical coupling. In accordance with this invention, before said step of depositing the bottom confinement layer, a barrier layer 30 opposing diffusion of said dopants is formed on said top face 4 . It would seem that the thickness of this layer must be between 100 nm and 2000 nm, preferably between 200 nm and 1000 nm. The manner in which a barrier layer of this kind can be formed has been described hereinabove. For example, it is a layer of pure silica 400 nm thick formed by oxidation. The other silica layers are then formed without difficulty by the FHD process. | A method of fabricating a component having a crystalline silicon substrate includes the steps of depositing a layer of silica onto a crystalline silicon substrate, this silica layer being doped with dopants, and then treating the substrate. Before the doped silica layer is deposited, a barrier layer is formed on the substrate, consisting of a barrier material opposing diffusion of the dopants. The doped silica layer is deposited onto this barrier layer. The invention finds one particular application in connecting flat bundles of fibers in communication networks. | 6 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made with Government support under Prime Contract No. DE-FC36-01GO10622 awarded by the Department of Energy. The Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to air presses for a papermaking machine, and, more particularly, to end seal arrangements therefor.
2. Description of the Related Art
Effective water removal from a paper web is essential to the papermaking process. Various types of presses, using some combination of juxtaposed rolls, have been used for some time now for water removal. Such presses rely on the hydraulic pressure created at the nip between each pair of juxtaposed rolls through which the paper web travels in a given press configuration to drive water from the paper web.
Various press have been developed which have attempted to add an element of a positive air pressure within the press assembly to more effectively force the water from the paper web. With respect to roll presses specifically, the rolls of the press have been configured to form a chamber with a positive air pressure being supplied therewithin.
However, the effectiveness of a multi-roll air presses is limited by the degree to which the air chamber thereof can be sealed. The areas of the press where sealing becomes quite crucial are those areas where the paper web and the membrane(s) carrying it do not pass, as the web/membrane(s) combination inherently acts to seal the region of each nip through which it passes. Those regions of the air press through which the paper web/membrane(s) combination does not pass are the opposed lateral ends of each nip and the opposed chamber ends defined by the two sets of roll end associated with the air press. Consequently, an end seal mechanism is provided at each chamber end, each such mechanism having a seal member which contacts each of the roll ends associated with that particular chamber end.
The ability of the end seal mechanism to efficiently seal a chamber is predicated on the application of a sufficient sealing force so that the seal member thereof maintains sealing contact with each of the roll ends of that chamber end. On the other hand, applying a force thereto that is greater than that needed to maintain a seal will cause the seal member to wear out quicker than is necessary.
Additionally, current end seal mechanisms do not facilitate adjustments in the positioning thereof or in the force ultimately applied on the seal member thereof With such systems, retraction of the end seal mechanisms for start-up and/or maintenance is not readily achieved. Additionally, it is difficult to optimize the forces applied to the seal member during start-up to initially achieve a sufficient seal therewith and yet promote a long life thereof.
What is needed in the art is an end seal mechanism in which the sealing force applied to the seal member thereof can be readily adjusted in order to achieve sufficient sealing while minimizing the rate of wear of the seal member; and an end seal mechanism which permits adjustments in the positioning thereof and in the amount of force placed upon the seal member thereof during various operational stages.
SUMMARY OF THE INVENTION
The present invention provides an end seal mechanism for an air press of a papermaking machine in which the force applied upon the end seal mechanism is independent of the air pressure inside the air press, the sealing force placed thereupon and the position thereof instead being controlled by an adjustable bias mechanism.
The invention comprises, in one form thereof, an air press for pressing a fiber web, the air press including a plurality of rolls and a pair of end seal arrangements. Of the plurality of rolls, each pair of adjacent rolls forms a nip therebetween. Further, each roll has a pair of roll ends, the plurality of rolls together forming two sets of roll ends. Each end seal arrangement coacts with one set of roll ends, the plurality of rolls and the pair of end seal arrangements together defining an air press chamber having an air chamber pressure. Each end seal arrangement is composed of at least one roll seal, including a first roll seal, and an adjustable bias mechanism. Each roll seal forms a seal with at least one roll end, and one side of the first roll seal being exposed to the air chamber pressure. The adjustable bias mechanism is configured for controlling a position of each roll seal relative to a respective at least one roll end and for adjusting a seal force between the roll seal and the respective at least one roll end.
In another form, the present invention comprises a method of achieving an end seal in an air press for pressing a paper web. The method includes a series of steps, the first of which is providing a plurality of rolls, each pair of adjacent rolls forming a nip therebetween. Each roll has a pair of roll ends, the plurality of rolls together forming two sets of roll ends. An end seal arrangement is positioned adjacent a respective set of roll ends, the plurality of rolls and the respectively positioned end seal arrangements together defining an air press chamber having an air chamber pressure. Each end seal arrangement is composed of at least one roll seal, including a first roll seal, and an adjustable bias mechanism. Each roll seal forms a seal with at least one roll end, and one side of the first roll seal being exposed to the air chamber pressure. The adjustable bias mechanism is configured for controlling a position of each roll seal relative to a respective at least one roll end and for adjusting a seal force between the roll seal and the respective at least one roll end. The seal force provided by the adjustable bias mechanism is increased to seat the set of roll ends within the end seal arrangement. Then, the seal force provided by the adjustable bias mechanism is decreased upon seating of the set of roll ends within the end seal arrangement. Finally, a substantially constant low net force is maintained on each roll seal upon the seating and during operation of the air press, the substantially constant low net force being maintained using the adjustable bias mechanism.
an end seal mechanism in which the sealing force applied to the seal member thereof can be readily adjusted in order to achieve sufficient sealing while minimizing the rate of wear of the seal member; and an end seal mechanism which permits adjustments in the positioning thereof and in the amount of force placed upon the seal member thereof during various operational stages.
An advantage of the present invention is the seal force applied to the seal member of the end seal mechanism can be readily adjusted in order to achieve sufficient sealing while minimizing the rate of wear of the seal member.
Another advantage is the end seal mechanism permits adjustments in the positioning thereof and in the amount of force placed upon the seal member thereof during various operational stages, thereby facilitating the optimization of both the forces applied to the seal member during start-up to initially achieve a sufficient seal therewith and the force needed to promote a long life thereof.
Yet another advantage is that the end seal mechanism can be designed so that the total force applied on a seal member is independent of the air chamber pressure in the air press and thus not subject to potential fluctuations in the air chamber pressure.
An even further advantage is that biasing springs can be eliminated from the design of the end seal mechanism due to the presence of the adjustable bias mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a schematic, side view of an embodiment of a papermaking machine of the present invention;
FIG. 2 is a schematic, partially-sectioned, fragmentary view of the end seal arrangement of FIG. 1; and
FIG. 3 is a schematic, partially-sectioned, fragmentary view of another embodiment of an end seal arrangement which can be employed in the papermaking machine shown in FIG. 1 .
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate at least one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIG. 1, there is shown a papermaking machine 10 for processing a paper web 12 which generally includes an air press assembly 14 and a plurality of conveyor rolls 16 .
Air press assembly 14 is constituted of a plurality of press rolls 18 juxtaposed with one another so as to define a plurality of nips 20 therebetween and an air chamber 22 thereamongst. Contacting a set of end faces 24 of press rolls 18 is an end seal arrangement 26 for closing off what would otherwise be an open end of air chamber 22 .
End seal arrangement 26 is composed of a piston holder 28 (FIG. 2 ), a seal piston 30 , a seal holder 32 , at least a first seal member 34 and an adjustable bias mechanism 36 . Each end seal arrangement 26 , by closing off an open end of air chamber 22 , further defines air chamber 22 , air chamber 22 having an air chamber pressure associated therewith. Piston holder 28 , seal piston 30 , seal holder 32 and first seal member 34 , by each specifically helping to define the boundary of air chamber 22 , are all exposed to the air chamber pressure.
Piston holder 28 acts as an outer structural member for end seal arrangement 26 . Piston holder 28 has a holder side wall 38 within which seal piston 30 is movably mounted. A gasket 40 is provided in seal piston 30 adjacent holder side wall 38 to ensure sealing contact therebetween. Seal piston 30 is movably mounted within piston holder 28 so to facilitate both the positioning of and the adjustment of a biasing force B applied on at least first seal member 34 .
Seal holder 32 extends from seal piston 30 opposite piston holder 28 and holds at least first seal member 34 therein. Seal holder 32 may either be integral with seal piston 30 , as shown in FIG. 2, or attached thereto. First seal member 34 is configured for directly contacting and sealing with end faces 24 . If only first seal member 34 is employed, first seal member 34 would advantageously made of a hard seal material and would be bonded directly to seal holder 32 , in addition to being exposed to air chamber 22 .
In the embodiment shown in FIG. 2, a further second seal member 42 is provided between and bonded to each of first seal member 34 and seal holder 32 . First and second seal members 34 , 42 can be considered roll seals as each seals with end faces 24 of press rolls 18 . In this instance where two roll seals are employed, second seal member 42 is advantageously made of a hard seal material, while first seal member 34 is favorably made of a soft seal material. The soft seal material deforms to form an efficient seal interface between end seal arrangement 26 and corresponding end faces 24 . Meanwhile, a hard seal material offers increased stiffness and wear resistance in comparison to a soft seal material. It is thus favorable for at least one of first and second seal members 34 , 42 to be made of a hard seal material in order to ensure sufficient seal stability and to minimize the rate at which seal wear occurs, as that wear rate is set by the hardest seal material present and in contact with each end face 24 . First and second seal members 34 , 42 may advantageously be made of a carbon fiber (CF) composite and/or polytetrafluoroethylene (PTFE) (commonly known by its trade name “Teflon®”), respectively.
First seal member 34 and, if present, second seal member 42 are sized and configured to maintain a separation distance 44 between each end face 24 and seal holder 32 to avoid wearing of seal holder 32 . As such, the time between seal member changes is dictated by the wear time needed to cause separation distance 44 to reach zero.
In the embodiment of FIG. 2, first seal member 34 and second seal member 42 together define a seal boundary 48 , seal boundary 48 encompassing a pressurized seal area 50 (schematically shown) therewithin. Similarly, inner holder face 52 of holder side wall 38 bounds and thereby defines a pressurized piston area 54 (schematically shown). Since, in the embodiment shown in FIG. 2, pressurized seal area 50 is approximately equal to pressurized piston area 54 , the pressures are balanced throughout seal boundary 48 , advantageously resulting in essentially no net chamber seal force F being applied upon first seal member 34 and/or second seal member 42 , regardless of the air chamber pressure. Under balanced pressure conditions, chamber seal force F is independent of the air chamber pressure.
In the embodiment of FIG. 2, both seal boundary 48 and holder side wall 38 define a similar dog-bone shape (FIG. 1 ). It is contemplated that those shapes could differ (e.g., seal boundary 48 could define a dog-bone shape and holder side wall 38 , a circle) as long as the areas encompassed thereby were essentially the same.
By achieving no net chamber seal force F regardless of air chamber pressure, the risk is avoided of underloading first seal member 34 and/or second seal member 42 in the case of a drop in air chamber pressure and of thus inviting possible leakage and/or slow seal breakage. Likewise, the risk of overloading first seal member 34 and/or second seal member 42 in the case of a rise in air chamber pressure and thus wearing out first seal member 34 and/or second seal member 42 at an even greater rate is also avoided when pressures are balanced. If, for example, pressurized piston area 54 were instead greater than pressurized seal area 50 , chamber seal force F would exist on first seal member 34 and/or second seal member 42 due to the air chamber pressure, chamber seal force F increasing with increasing air chamber pressure. In certain instances, it may prove desirable to have pressurized piston area 54 be slightly greater than pressurized seal area 50 so that a small chamber seal force F and, thus, a sealing function would exist in all operational situations.
Adjustable bias mechanism 36 is configured for controlling a position of first seal member 34 and, if present, second seal member 42 relative to a respective set of end faces 24 and for providing a biasing force B between each of first seal member 34 and second seal member 42 , if present, and respective end faces 24 . Adjustable bias mechanism 36 is capable of generating the smallest possible biasing force B needed to create a suitable seal between each of first seal member 34 and second seal member 42 , if present, and respective end faces 24 . It is advantageous to apply the smallest possible biasing force B needed to create a suitable seal as seal wear can be minimized thereby.
Adjustable bias mechanism 36 is advantageously capable of ensuring that first seal member 34 and second seal member 42 , if present, are engaged when air chamber 22 is pressurized; retracting end seal arrangement 26 for startup and maintenance; and regulating biasing force B such that biasing force B is increased during seal break in and decreased once seated to maximize seal life. The ability to retract end seal arrangement 26 when nips 20 are being closed avoids the possibility of first seal member 34 and/or second seal member 42 being broken by end faces 24 catching thereon. Further, since biasing force B is independent of chamber seal force F, even if chamber seal force F is not zero, end seal arrangement 26 can be closed and loaded independently of air chamber pressure. As a result of such independence, such a design can advantageously eliminate the need for springs in the end seal arrangement.
In the embodiment shown in FIG. 2, adjustable bias mechanism 36 includes an air cylinder 56 and an air cylinder shaft 58 . Air cylinder 56 may either be mounted outside of piston holder 28 (as shown in FIG. 2) or inside thereof (not shown). Air cylinder shaft 58 is selectively driven by air cylinder 56 and operably connects air cylinder 56 with seal piston 30 . If air cylinder 56 is mounted outside of piston holder 28 with air cylinder shaft 58 accordingly extending therethrough, appropriate seals (not shown) are advantageously provided between air cylinder shaft 58 and piston holder 28 to minimize leakage therebetween.
In operation, end seal arrangement 26 is positioned adjacent a set of end faces 24 of press rolls 18 . Air cylinder 56 of adjustable biasing mechanism 36 is first used to apply an increased biasing force B during break in of first and second seal members 34 , 42 . Biasing force B is then decreased once seated to a minimum force needed to maintain a sufficient seal between end faces 24 and first and second seal members 34 , 42 to maximize seal life thereof
End seal arrangement 60 , shown in FIG. 3, is a second embodiment of the end seal arrangement of the present invention. End seal arrangement 60 is composed of a piston holder 62 , a seal piston 64 , a seal holder 66 , a first seal member 68 , a second seal member 70 (optional in the same manner as the first embodiment, requiring first seal member 68 to be bonded directly to seal holder 66 if not used) and an adjustable bias mechanism 72 . Each end seal arrangement 60 , by closing off an open end of air chamber 22 , further defines air chamber 22 , air chamber 22 having an air chamber pressure associated therewith. Piston holder 62 , seal piston 64 , seal holder 66 and first seal member 68 , by each specifically helping to define the boundary of air chamber 22 , are all exposed to the air chamber pressure.
Only those features which differ from those of the first embodiment will be discussed in detail with respect to this second embodiment.
Piston holder 62 , seal piston 64 and o-rings 74 together define adjustable bias mechanism 72 . Adjustable bias mechanism 72 has an adjustable biasing pressure therein, a net biasing force B 1 produced thereby being a function of the difference between the biasing pressure therein and the atmospheric pressure outside of end seal arrangement 60 . In a manner similar to that for the first embodiment, piston holder 62 encompasses a pressurized piston area 76 , and the combination of first and second seal members 68 , 70 bounds and thereby defines pressurized seal area 78 , and pressurized piston area 76 is essentially equal to pressurized seal area 78 , thereby producing no net chamber seal force F 1 .
As such, the only net force placed on first and second seal members 68 , 70 is one generated by adjustable bias mechanism 72 , i.e., biasing force F 1 . Thus, if the biasing pressure is equal to atmospheric pressure, biasing force B 1 is equal to zero, resulting in no downward force on first and second seal members 68 , 70 . However, a biasing pressure in excess of atmospheric produces a positive biasing force B 1 , resulting in a downward force on first and second seal members 68 , 70 . Conversely, first and second seal members 68 , 70 can be retracted from end faces 24 by applying a less than atmospheric pressure (e.g., a vacuum) within adjustable bias mechanism 72 .
Other features of the second embodiment which differ from the first are apparent in FIG. 3 . Seal holder 66 is separate from seal piston 64 and is attached thereto via a holder attachment mechanism 80 (e.g., a bolt or screw). Using a separate seal holder 66 eases seal member replacement but introduces the requirement of attaining a sufficient seal between seal holder 66 and seal piston 64 .
Both lateral and vertical movement of seal piston 64 relative to piston holder 62 is limited by piston attachment mechanism 82 (e.g., a bolt or other attachment pin). Piston attachment mechanism 82 extends through seal piston 64 and is mounted in piston holder 62 . Piston attachment mechanism 82 is supplied with a head 84 , head 84 acting as a vertical movement stop for seal piston 64 .
Additionally, an indicator light 86 (e.g. an LED) is provided on head 84 to act as a visual indicator of a gap and thus a potential leak site between end faces 24 and end seal arrangement 60 . Such an indicator light 86 could also be advantageously employed within the first embodiment.
Operation of end seal arrangement 60 is similar to that of end seal arrangement 26 with the exception of using a variable biasing pressure within adjustable bias mechanism 72 to produce the desired biasing force B 1 .
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | An air press for pressing a fiber web includes a plurality of rolls and a pair of end seal arrangements. Of the plurality of rolls, each pair of adjacent rolls forms a nip therebetween. Further, each roll has a pair of roll ends, the plurality of rolls together forming two sets of roll ends. Each end seal arrangement coacts with one set of roll ends, the plurality of rolls and the pair of end seal arrangements together defining an air press chamber having an air chamber pressure. Each end seal arrangement is composed of at least one roll seal, including a first roll seal, and an adjustable bias mechanism. Each roll seal forms a seal with at least one roll end, and one side of the first roll seal being exposed to the air chamber pressure. The adjustable bias mechanism is configured for controlling a position of each roll seal relative to a respective at least one roll end and for adjusting a seal force between the roll seal and the respective at least one roll end. | 3 |
This application is a continuation-in-part of application Ser. No. 284,885, filed Dec. 15, 1988, which was a continuation-in-part of application Ser. No. 140,922, filed Dec. 28, 1987, which was a continuation-in part of application Ser. No. 004,729, filed Jan. 20, 1987 all now abandoned.
BACKGROUND OF THE INVENTION
The present invention is directed to a method of making a sheeted crosslinked cellulose and the product resulting from the process. The invention is especially directed toward a crosslinked cellulose sheet which can later be easily reslurried in water without excessive fiber breakage.
Crosslinked cellulose products have been described in the chemical literature for many years. These products are normally made by reacting a material, usually bifunctional, that will tie together hydroxyl groups on neighboring cellulose chains. Formaldehyde and various derivatives of urea have been the crosslinking agents which have received the greatest study. However, many other materials which have actual or latent bifunctional reactive groups have also been reported.
Crosslinked celluloses are of great commercial importance in the textile industry where they are widely used for the production of wash-and-wear and other wrinkle-resistant types of fabrics. Crosslinked cellulose fluff has also been described for use in disposable absorbent products such as diapers. Here advantages is taken of the fact that crosslinked fibers are normally stiffer than their untreated counterparts. The fluff products formed from these fibers are of somewhat lower density (or greater bulk) and tend to hold retained liquid better under compressive forces encountered during use of the product.
While the advantages contributed to disposable absorbent products by crosslinked cellulose fibers are real, products using these crosslinked fibers have never become commercially important. This is apparently because of the difficulty of making a sheeted crosslinked fiber product that can be later refiberized at the point of use without creation of an excessive amount of fines. Unfortunately, crosslinking also results in considerable fiber embrittlement. Additionally, most of the crosslinking agents which have been used serve to give both chemical and physical bonding between adjacent fibers in the sheets. This, in addition to the increased fiber brittleness, has made mechanical wet or dry defiberization of sheeted crosslinked pulps impractical. In an effort to overcome this problem, various workers have considered treating sheeted pulp with a latent crosslinking material, fluffing, and then carrying out the crosslinking reaction by heating the cellulose fluff. An example of this is seen in Bernardin, U.S. Pat. No. 3,224,926. Van Haaften, Canadian Patent 806,352 treats loose fibers with a crosslinking material and catalyst. These moist fibers are then expanded into a loose fluffy condition and cured.
The stiffness of crosslinked cellulose fibers can add desirable properties to certain sheeted pump products. Here it is typical to use only a portion of crosslinked fibers in the ultimate product. Attempts to do this have encountered the same problems mentioned earlier. If a product is crosslinked in sheeted form, it becomes very difficult to redisperse without serious fiber breakage by normal wet repulping processes employed in paper mills. As noted before, there are two apparent reasons for this. The strength of a sheeted cellulose product is developed in part by mechanical entanglement of the fibers but, much more so, by hydrogen bonding in those areas where fibers overlap are in intimate contact with each other. This hydrogen bonding develops only when the fibers are dry, in a crosslinked sheeted product, when the crosslinking reaction is normally carried out by heating after the sheet has been fully dried, two phenomena can occur. One of these is interfiber crosslinking. The reaction occurs in areas of intimate fiber-to-fiber contact and serves to chemically bind the fibers together. Perhaps of even greater importance, many of the crosslinking materials that also form thermosetting adhesives under the heated conditions used in the crosslinking reaction. Scanning electron micrographs of heated dimethylolurea treated fibers show many small spherical nodules of ureaformaldehyde resin on the surface and within the fiber lumen. These nodules serve to adhesively bond adjacent fibers so that it is very difficult to separate them under any conditions without considerable fiber breakage. Because the crosslinked fibers tend to be so brittle, the fibers the themselves will often break leaving the bonded areas between adjacent fibers intact. There is a related side issue to this phenomenon. It is still an unresolved question as to how much of the crosslinking reaction is a surface phenomenon as opposed to an internal one.
Earlier workers in the field have also tried to deal with the problem of making a sheeted cellulose pulp product containing only a portion of crosslinked fibers. As one example, Bernardin, in U.S. Pat. No. 3,434,918, treats sheeted fiber with a crosslinking agent and catalyst. This is then wet aged to insolublize the crosslinker, so-called "wet fixation." This wet aged fiber is then redispersed before curing. The redispersed fiber can be mixed with untreated fiber and the mixture sheeted. The final product is then heat cured. In a variation of this process the same inventor, in Canadian Patent 813,616, heat cures crosslinked fibers as a fluff and then mixes this product with conventional papermaking fibers.
These mixtures of crosslinked fibers with untreated fibers are potentially useful for making products such as filter media, tissues, and towelling where high bulk and good water absorbency are desired without excessive stiffness in the product. Freimark et al, in U.S. Pat. No. 3,755,220, describe making a soft, high wet strength sheet, although this does not use crosslinked fibers. These inventors utilize well known debonders or softeners with cationic wet strength resins to gain an increase in the ratio of wet to dry tensile strength, usually without serious loss in absolute values of wet tensile strength. The debonder itself can be cationic or anionic and may be added to the papermaking stock prior to or following the addition of the wet strength resin.
In U.S. Pat. No. 4,204,054, Lesas et al describe spraying unsheeted bulk fibers with a solution of formaldehyde, formic acid and hydrochloric acid. These fibers are then immediately dispersed in a hot air stream at about 170°-200° C. 1-20 seconds. This appears to give primarily surface area crosslinking without serious effect on fiber flexibility. The inventors note that 10-40% of these fibers can be mixed with conventional fibers to give a sheeted product with good flexibility and water absorbency.
Unfortunately, the problems encountered handling bulk fibers; i.e., those in individual loose form as opposed to a sheeted product, have been so great as to be commercially nearly insurmountable to the present time. The fiber must be dried by flash drying or some similar procedure where it is usually suspended in a hot air stream. The dried fiber is then baled or bagged. Because of the very short fiber length, compactly packaging a loose fiber form of wood pulp is technically very difficult and expensive. An alternative procedure, where the loose fibrous product might be prepared at the ultimate point of consumption, has been even more unattractive and has met with a wall of resistance by potential consumers.
The reader who might be interested in learning more detail of the chemistry of cellulose crosslinking can refer to any of the standard texts on cellulose. One resource which treats the subject quite thoroughly is by Tersoro and Willard in Cellulose and Cellulose Derivatives, Bikales and Segal, eds., Part V, Wiley-Interscience, New York, (1971), pp. 835-875.
Reference was made to use of fiber debonders, also called sheet softeners in the earlier comments relating to U.S. Pat. No. 3,755,220. These materials can be generally classified as surfactants which are applied to the fiber while it is still wet, before any hydrogen bonding has occurred. Most typically they are cationic in nature, based on quaternary ammonium compounds which have one or more fatty substituents. Although not as commonly used, nonionic and anionic types are also commercially available, Frequently a combination of a cationic and nonionic type may be employed. These products are widely used within the pulp and paper industry and are commercially available from a number of supplies. Similar products are used in the textile industry.
Debonders serve to make a softer sheet by virtue of the fatty portion of the molecule which interferes with the normal hydrogen bonding. They are quite commonly used in the manufacture of fluff pulps which will be later converted into absorbent products such as disposable diapers. The use of a debonder can reduce the energy required to produce a fluff to half or even less than the required for a nontreated pulp. This advantage is not obtained without a price, however, Many debonders tend to reduce water absorbency as a result of hydrophobicity caused by the same fatty long chain portion which gives the product its effectiveness. In order to overcome this problem, some manufacturers have formed adducts of ethylene or propylene oxide in order to make the products somewhat more hydrophilic. Those interested in the chemistry of debonders will find them widely described in the patent literature. The following list of U.S. patents provides a fair sampling, although it is not intended to be exhaustive: Hervey et al., U.S. Pat. Nos. 3,395,708 and 3,554,862; Forssblad et al, U.S. Pat. No. 3,677,886; Emanuelsson et al., U.S. Pat. No. 4,144,122; Osborne, III., U.S. Pat. No. 4,351,699; and Hellsten et al., U.S. Pat. No. 4,476,323. All of the aforementioned patents describe cationic debonders. Laursen, in U.S. Pat. No. 4,303,471, describes what might be considered a representative nonanionic debonder.
U.S. Pat. No. 3,844,880 to Meisel, Jr. et al. describes the use of deposition aid (generally cationic), an anionic resin emulsion, and a softening agent which are added sequentially to a pulp furnish to produce a soft product having high wet and dry tensile strength. The opposite situation; i.e., low wet tensile strength, is preferred for a pulp which is to be later reslurried for some other use.
Croon et al., in U.S. Pat. No. 3,700,549, describe a cellulose fiber product crosslinked with a polyhalide, polyepoxide, or epoxyhalide under strongly alkaline conditions. Epichlorohydrin is a preferred material. In their examples Croon et al teach the use of their treated fiber in absorbent products such as diapers and sanitary napkins. All of the crosslinking materials are insoluble in water. Croon et al teach three methods to overcome this problem. The first is the use of vigorous agitation to maintain the crosslinking agent in a fine droplet-size suspension. Second is the use of of a polar cosolvent such as acetone or dialkylsulfoxides. Third is the use of a neutral (in terms of being a nonreactant) water soluble salt such as magnesium chloride. In a variation of the first method a surfactant may be added to enhance the dispersion of the reactant phase. After reaction the resulting product must be exhaustively washed to remove the necessary high concentration of alkali and any unrelated crosslinking materials, salts, or solvents. The method is suitable only for cellulosic products having a relatively high hemicellulose content. A serious deficiency is the need for subsequent disposal of the toxic materials washed from the reacted product. The Croon et al material would also be expected to have all other well known disadvantages incurred with trying to sheet a stiff, brittle crosslinked fiber.
Steiger, in U.S. Pat. No. 3,658,613, teaches a method for "wet" crosslinking a sheeted pulp product so that it can later be defiberized dry with reduced fiber breakage and knot content. The reaction is carried out with a crosslinker such as formaldehyde, ureaforms, glyoxal and halohydrins under very strongly acidic conditions; e.g., in a reaction medium containing 50% by volume of 37% hydrochloric acid, for about 30 minutes. The pulp after reaction must be neutralized by a mild alkali and washed prior to drying. The strongly acidic reaction conditions and difficulty of supporting a saturated wet sheet for the necessary operations over the required period of time would pose almost insuperable barriers against commercial production.
U.S. Pat. No. 3,819,470, Shaw et al. teach the reaction of a "substantive compound" with cellulose to form a pulp product which can later be refiberized in water. A debonder may be used at various points of addition in the process. The substantive compound is apparently a cationic polymer, such as a cationic ureaform wet strength agent. The inventors clearly teach against the use of crosslinking agents and offer a number of reasons why their use would not be suitable in the process. Low retention of the polymer, only about 50%, would seriously affect the economics of the process and create a serious waste disposal problem.
Chung, in U.S. Pat. No. 3,440,135, teaches the manufacture of a crosslinked cellulose product which is then later dried in loose fiber form. Sheeted pulp is treated in a bath of a crosslinking agent such as dimethylolurea. A surfactant may optionally be included to improve wet dispersion of the pulp before the drying step. The inventor notes the critically of wet aging the treated product in the range of 16-48 hours before it is refiberized and dried in a hot air suspension. This aging requirement would virtually doom the commercial possibilities for the process since it would impose on the mill the requirement for keeping a large inventory of wet sheeted pulp. The additional process expense and space requirements would make the cost of the product prohibitively high.
To the knowledge of the present inventor, no one except Chung as noted above used a debonder with a cellulose pulp which is also treated with a crosslinking agent. One skilled in the art would not expect this to be an effective combination, i.e., they would expect the interfiber bonding propensities of the crosslinking agents to completely overpower any advantage in the reduction of wet or dry strength that might be contributed by the debonding agent. The deficiencies that make the Chung process commercially impractical have already been noted.
SUMMARY OF THE INVENTION
The present invention is a method of making wet formed, sheeted crosslinked cellulose and the products produced thereby which can be easily reslurried to a free fiber condition without excessive fiber breakage. The method comprises including within the sheet while still wet a debonding agent and water soluble or water dispersable latent cellulose crosslinking agent. The sheet thus treated is dried and, during or after drying the crosslinking agent reacts with the cellulose. In the most preferred form of the invention, the debonding agent is added to an aqueous slurry of cellulose fibers prior to sheet formation and a latent crosslinking agent is added subsequent to sheet formation. This can be readily accomplished by spraying an aqueous solution or dispersion of the crosslinking agent onto the sheet while it still on the forming wire or in the press section of the paper machine. However, it is within the scope of the invention to add both the debonding agent and the latent crosslinking agent to the wet sheet following sheet formation. In this case it is preferable to add the debonding agent to the wet sheet prior to the addition of the latent crosslinking agent. The latent crosslinking agent should be added to sheeted cellulose while it is at a moisture content greater than about 10%, preferably greater than about 30%. Immediately after sheet formation the sheet is conventionally dried using standard papermill equipment.
The process of the invention is carried out at a pH generally above 4. It is not necessary to carry out the crosslinking reaction or to handle the product under highly acidic conditions.
It is within the scope of the invention to use a debonding agent which may be either cationic, nonionic or anionic in nature.
The latent crosslinking agent may be selected from any of the following well known materials which serve this function. Preferred types are selected from urea derivatives such as methylolated urea, methylolated cyclic ureas, methylolated lower alkyl substituted cyclic ureas, dihydroxy cyclic ureas, lower alkyl substituted dihydroxy cyclic ureas, methylolated dihydroxy cyclic ureas, and mixtures of any of these types. A presently preferred latent crosslinking materials is dimethyloldihydroxyethyleneurea (DMDHEU, 1,3-dihydroxymethyl-4,5-dihydroxy-2-imidazolidinone). This material is readily commercially available in a stable form. Other urea-based materials which are eminently suitable include dimethylol urea (DMU, Bis[N-hydroxymethyl]urea), dihydroxethyleneurea (DHEU, 4,5-dihydroxy-2-imidazolidinone), dimethylolethylene area (DMEU, 1,3-dihydroxymethyl-2-imidazolidinone), and 4,5-dihydroxy-1,3-dimethyl-2-imidazolidinone (DDI, dimethyldihydroxyethyleneurea).
In addition to those latent crosslinking agents based on urea, other materials that are suitable are polycarboxylic organic acids. Among these 1,2,3,4-butanetetracarboxylic acid is a presently preferred material.
All of the crosslinking agents just described may be reacted with the cellulose either during normal drying of the sheeted material or subsequent to this time by raising the dried sheet to an elevated temperature, preferably above 100° C.
A neutral or acidic catalyst may be included with the latent crosslinking agent to increase the reaction rate between the crosslinker and the cellulose. Acidic salts are particularly useful as catalysts when the urea-based materials are employed. These salts may typically be ammonium chloride or sulfate, aluminum chloride, magnesium chloride or mixtures of these or many other similar materials. Alkali metal salts of phosphorous-containing acids, such as sodium hexametaphosphate and sodium hypophosphite, with or without additional oxalic acid, are useful catalysts for 1,2,3,4-butane carboxylic acid.
The crosslinking agent is typically present in an amount in the range of 2-200 kg/t, preferably 20-100 kg/t, of cellulose fiber. Similarly, the debonding agent is generally present in an amount of about 0.1-20 kg/t, preferably 1-10 kg/t, of cellulose fiber.
A particular advantage of the new process is found in the lack of any need for washing the sheeted crosslinked product after the crosslinking reaction is completed.
It is an object of the present invention to provide a sheeted crosslinked cellulose product which can be readily reslurried in water to a free fiber condition without excessive fiber breakage or energy input.
It is a further object of the invention to provide a method of manufacturing such a product.
It is another object to provide a method and product as described which can be conveniently and readily made on conventional papermaking equipment.
It is yet another object to provide a product of the types described which can be readily redispersed in water and mixed with other types of fibers, which mixtures can be resheeted to give products having novel and useful properties.
It is an additional object to provide a sheeted crosslinked cellulose paper product that can be manufactured on standard unmodified papermaking equipment in a wholly conventional manner.
It is also an object to manufacture a crosslinled cellulose product under neutral or acidic conditions in which the pH is not below about 4.
These and many other objects will become readily apparent to those skilled in the art upon reading the following detailed description.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The sheeted crosslinked cellulose products of the present invention are intended for use as manufactured, or for remanufacture by a process that involves redispersing the product in water, usually for admixture with other fibers, followed by resheeting. It is not a primary goal or intention of the invention to produce sheeted products useful in processes that involve dry mechanical defibering, even though some species may perform satisfactorily under these conditions. The present invention provides a sheeted crosslinked cellulosic product that contributes good bulk and absorbency to a remanufactured sheet with little or not loss of fiber integrity or length during the remanufacturing process.
While the individual use of debonding agents and crosslinking reagents have been both known for some time in the pulp and paper industry, these have never before been used in combination in a sheeted pulp product, to the knowledge of the present inventor. It was totally unexpected that the debonders would continue to function as such that treatment of and reaction of the fibers with crosslinking materials. This is especially the case since many crosslinking agents will, at least to some extent, form polymers as a side reaction while reacting with the cellulose. In many cases these polymeric side reaction products serve as powerful adhesive materials. As one example, the efficiency of urea-based polymers as bonding agents for cellulosic materials is well known. Many of the precursors of these urea adhesives are the identical materials that are also highly effective cellulose crosslinking agents.
To the inventors best knowledge, any latent cellulose crosslinking composition is effective in the present invention. Those that can be reacted at relatively low temperatures in short periods of time during or after normal drying are preferred from a technical and economic standpoint. The urea-based crosslinking materials seem to fill this requirement well since their reaction speed can be greatly accelerated with small amounts of inexpensive acidic salt catalysts. Other classes of crosslinking agents can probably be similarly accelerated as well. No representation is made here that any of the processes described in the following examples have been optimized.
In similar manner, it appears that any class of debonding agent will be satisfactory, although there is some indication that cationic types may be superior to nonionic or anionic materials. Again, the systems reported here have not been optimized.
Cationic debonders are most usually based on quaternary ammonium salts having one or two lower alkyl substituents and one or two substituents that are or contain a fatty, relatively long chain hydrocarbon. Most of these fall into one of four general types as follows: ##STR1## where R 1 and R 2 are methyl, ethyl, or hydroxyethyl, R 3 is a hydrocarbon having 1-40 carbon atoms, R 4 is a hydrocarbon having 10-40 carbon atoms, E is an oxyalkylene group having 2 or 3 carbon atoms, m is an integer from 1-20, n is an integer from 0-20, and X is Cl or SO 4 , said hydrocarbon substituents being selected from linear and branched alkyl or alkenyl groups, and branched and linear alkyl and alkenyl substituted phenyl groups. Most typically R 3 will have from 1-22 carbon atoms and R 4 from 10-22.
Originally most debonders were Type 1 fattyalkyl di- or trimethyl ammonium compounds. These have now been superceded in many cases by the other types since they may induce an undesirable hydrophobicity.
The Type 2 debonders, diamidoamine types, are quite inexpensive and are widely used as fabric softeners.
Dialkyl alkoxylated quaternary ammonium compounds (Type 3) are widely used in making fluff pulps for disposable diapers since the polyethylene or propylene oxide chains give better hydrophylicity and cause less degradation of absorbency, especially when compared with Type 1 compositions.
The imidazoline materials that comprise Type 4 materials are somewhat newer materials. However, they are also now widely used.
Nonionic materials that can serve as debonders comprise a very large class of materials. Principal among them are adduct type reaction products of fatty aliphatic alcohols, fatty alkyl phenols and fatty aromatic and aliphatic acids with ethylene oxide, propylene oxide or mixtures of these two materials. Most typically the fatty portion is a hydrocarbon chain having at least 8, more typically 10-22, carbon atoms. Other useful nonionic debonders include partial fatty acid esters of polyvalent alcohols and their anhydrides wherein the alcohol or anhydride has 2-8 carbon atoms.
Anionic debonders also include a large class of materials, including many having surfactant properties. In general these are sulfated fats, fatty esters, or fatty alcohols. They also include fatty alkyl substituted aromatic sulfonic acids. The fatty substituent groups may have from 8-40 carbon atoms, more typically from 10-22 carbon atoms.
In the most preferred practice of the invention the debonder will be added to the cellulose fiber stock at some point before the headbox of the paper machine. When anionic or nonionic debonders are used it is normal practice to also use a cationic retention aid at the point of or immediately prior to their addition. Otherwise, they will have very poor substantivity to the cellulose fibers. It is within the scope of the invention to add both the softener and latent crosslinking agent after formation of the sheet. In this case it is not always necessary to use retention aids with nonionic or anionic debonders.
The following examples will illustrate the best modes presently known to the inventor for carrying out the present process and making the resulting products.
EXAMPLE 1
The following procedure was used to make laboratory handsheets for evaluation. A 25 g (dry weight) sample of unrefined cellulose pulp was reslurried in a Waring Blendor at about 2% consistency for 20 seconds. After 5 seconds of agitation, one of the commercially available softening agents was added to the blender in amounts ranging from 0% (for control samples) to 2% based on dry pulp. Most typical usage was about 0.5% (5 kg/t), on an as received basis. The reslurried, softener treated pulp was further diluted to a volume of about 6800 mL with water. This slurry was formed into a sheet on a standard 8×8 inch(203×203 mm) Noble and Wood laboratory sheet mold, using a 150 mesh stainless steel screen. The sheet was removed from the former and pressed between synthetic fiber felts so that the moisture content was reduced to about 50%.
The moist sheet prepared as above was then immersed into a bath containing a known concentration of a latent crosslinking agent and catalyst, if the latter component was used. After immersion the sheet picked up sufficient treating liquid so that its consistency was reduced to about 13.5%. If was again pressed between felts to about 50% fiber content. It can be readily calculated to show that the final pickup of latent crosslinking agent and catalyst, based on pulp, was about 85% of the concentration in the bath. The handsheet was then drum dried to about 5% moisture content.
Depending on the particular crosslinking agent and/or catalyst used, the crosslinking reaction with the cellulose occurred either during the drying step or in an oven curing stage following drying.
EXAMPLE 2
The bulk density of a crosslinked pulp sheet is dependent on a number of interacting factors; the physical nature of the cellulose, the type and amount of softener used, the type and amount of crosslinking agent and/or catalyst used, and the time and temperature of the crosslinking reaction. The effect of time-temperature relationship for one set of conditions can be seen in the following example using laboratory handsheet samples.
A bleached Douglas-fir kraft pulp was reslurried as described in Example 1 and treated with 0.5% as received of Berocell 584 softener. This material is a quaternary ammonium based softener believed to be principally a fatty substituted oxyalkylatedphenol dialkyl quaternary ammonium chloride (see the Type 3 quaternary formula noted earlier). This is compounded using 30% of the quaternary compound with 70% of a nonionic polyoxyalkylene composition. It is available from Berol Chemical Co., Reserve, La. After sheeting and pressing, the handsheets were treated with a 10%, as received basis, aqueous solution of Arotex 900 latent crosslinking agent. Arotex is a registered trademark of and is available from American Cyanamid Company, Wayne, N.J. It is believed to be a dimethyloldihydroxyethyleneurea product and is sold as an aqueous solution at about 45% solids concentration. For every 100 parts of the Arotex 900 solution, 30 parts by weight of Arotex Accelerator 9 catalyst solution were used. This is a 30% by weight solution of acidic salts believed to be aluminum and magnesium chlorides. Retention of the latent crosslinking agent, on a 100% solids basis, was calculated to be 3.78% of the dry cellulose present. The dried sheets were cured at 150° C. for 3 minutes.
In order to determine the reslurring and bulking properties of the treated fiber a 3.5 g, dry weight, sample was torn into small pieces and reslurried in about 2 L of water in a British Disintegrator. Agitation was continued until the slurry was smooth and free of obvious knots or fiber bundles. The number of revolutions to this point was counted and is an indicator of the ease with which the material can be redispersed. The slurry was then sheeted in a standard 61/4 in (159 mm) TAPPI sheet mold. After draining it was vacuum couched but was then drum dried without pressing. Bulk density was measured on the dried samples. High bulk values are generally as indication of high fiber stiffness. However, high bulk values cannot be obtained if there has been any significant amount of fiber breakage during reslurring. For this reason, bulk density is also strongly indicative of fiber length and of any fiber damage during reslurrying.
TABLE I______________________________________ Control Crosslinked Pulp (Un- No De- De- treated) bonder bonded______________________________________Disintegration Energy, revs. 15,000 125,000 20,000Handsheet Bulk Density, cm.sup.3 /g 3.1 9.5 16.5______________________________________
EXAMPLE 3
The reaction conditions; i.e., time, temperature, and catalyst concentration, between the potential crosslinking agent and the cellulose affect the bulking potential and ease of reslurrying of the sheeted product. A series of handsheets was made according to the procedures outlined in Examples 1 and 2. However, this time the amount of as received Arotex 900 in the treatment bath was varied in 5% steps between 0% and 20%, resulting in pickups by the fiber varying between 1.9 and 7.6%, as calculated on a dry materials basis. A constant weight ratio of 10:3 between as received crosslinker and catalyst was maintained for all samples. This ratio may be expressed as 5:1 on a dry solids basis. The resulting 203×203 mm Noble and Wood handsheets were resheeted as in Example 2 in the TAPPI sheet mold to obtained samples for bulk densities. Results were as follows:
TABLE II__________________________________________________________________________Effect of Curing Conditions on Handsheet Bulk DensityTAPPI Handsheet Bulk Densities, cm.sup.3 /g Reaction TemperatureCrosslinker Solids 120° C. 140° C. 160° C.Based on Pulp, % 1 min 3 min 5 min 1 min 3 min 5 min 1 min 3 min 5 min__________________________________________________________________________0 3.21.89 3.8 6.7 5.2 7.6 9.5 10.5 10.3 14.1 15.83.78 9.7 13.2 16.0 15.3 15.7 17.7 19.3 14.6 14.55.67 6.7 16.8 20.4 18.6 17.7 16.7 20.0 14.8 14.87.56 9.0 19.3 19.7 19.6 16.1 17.4 20.0 -- --__________________________________________________________________________
It is readily apparent that with the present crosslinker system, TAPPI sheet bulk density increased directly with increases in crosslinker usage, reaction time, and reaction temperature. However, little change was seen in sheet bulk with increase in reaction time from 3 to 6 minutes, especially at the two higher curing temperatures. Likewise, there does not appear to great advantage at reacting at the higher temperature of 160° C. compared with 140° C. In fact, at higher crosslinker usages the higher temperature may cause undesirable fiber embrittlement.
EXAMPLE 4
A series of samples was made using a 10% Arotex 900 bath treatment and comparing the Berol 584 softener, used in Examples 2 and 3, with a nonionic softener and a nonionic/cationic softener combination. The nonionic material was Triton X-100, a nonylphenol type. Triton is a registered trademark of and the product is available from Rohm and Haas Co., Philadelphia, Pa. The samples without softener and with the cationic softener were made as in Example 2. In the case where the nonionic softener by itself was used in combination with the crosslinking agent, both were included in the crosslinker bath and no softener was added prior to sheet formation. Estimated concentration of nonionic material solids incorporated into the final product, based on dry cellulose, is 0.8%. When the cationic/nonionic combination was used, the cationic was added as in Example 2, prior to sheeting, and the nonionic was included with the crosslinking agent as just described. In addition to sheet bulk density values, disintegration energy was estimated by noting the number of British Disintegrator revolutions necessary to give a uniform fiber dispersion without nots or fiber clumps. Results were obtained as shown in Table III.
TABLE III______________________________________ Disintegration Handsheet BulkSample Energy, revs Density, cm.sup.3 /g______________________________________No debonder 120,000 11.9Cationic debonder 22,500 24.7Nonionic debonder 62,500 16.9Cationic/nonionic 62,500 18.4______________________________________
The nonionic softener significantly improves ease of dispersibility and increases bulk value. However, it is not as effective here as the cationic debonder and, when used in combination under these conditions, reduces the effectiveness of the cationic material.
EXAMPLE 5
A major use of the products of the invention is expected to be in filtration medium. Here some portion of the crosslinked fiber would normally be repulped, blended with untreated fiber, and resheeted. A major contribution of the crosslinked fiber is porosity control and, in some cases, it can make higher porosities possible than can now be readily attained. One common measure of the expected behavior of a filter medium is air porosity. A number of test procedures are employed. The particular one chosen is in part dependent on the expected air resistance of the sheet. The tests on the present product were conducted on sheets having a basis weight of 160+5 g/m 2 by measuring the pressure drop caused by an air flow of 0.085 m 3 /min.
Sheets were formed using 3.5 g, dry weight, of pulp dispersed in a British Disintegrator in about 2 L of water until a uniform slurry was produced. Sheets were formed in a standard laboratory British Sheet Mold, couched at 68.9 kPa, drum dried between blotters, and heated for 1.5 minutes at 150° C. to react the cellulose and crosslinker. Before testing sheets were conditions to equilibrium at 50% RH at 23° C.
For the tests reported below in Table IV, Arotex 900 was used in bath concentrations of 1, 3, 5, 10, and 15% and the fiber was treated before sheeting with 0.5% berocell 584 debonding agent.
TABLE IV______________________________________Bulk and Air Resistance of Crosslinked FiberCrosslinker Solids Handsheet Bulk Air ResistanceBased on Pulp, % Density, cm.sup.3 /g Pressure Drop, mm______________________________________0 3.7 370.38 -- 191.13 8 4.31.89 10 3.03.78 21 0.55.67 23 0.5Untreated Control.sup.(1) 5.5 3.3______________________________________ .sup.(1) A commercially available prehydrolyzed, cold caustic extracted southern pine kraft pulp widely used in filter media.
The desirable air resistance properties contributed by the readily redispersible crosslinked cellulose pulp are immediately apparent.
EXAMPLE 6
Another expected major use of the products of the present invention is in tissues and toweling in order to maintain high bulk and softness with good water absorbency. To show the effectiveness of the crosslinked material, a sample was prepared as in Example 3 using a bath concentration of 15% Arotex 900. This resulted in a pickup of crosslinker solids based on dry pulp of about 5.7%. Varying amounts of this product were reslurried and added to fiber obtained by reslurrying two popular brands of toilet tissue. One of these, Tissue A, was a conventional hot drum dried product while the other, Tissue B, was originally dried using heated air passed through the tissue to maintain softness.
Sheets were formed in a standard laboratory British Sheet Mold as described in the previous example using 0.44 g, dry weight, of fiber to give a final sheet having a basis weight of about 24 g/m2. In addition to the bulk density value, softening efficiency of the crosslinked pulp in the ultimate sheet was estimated. This was calculated by taking the ratio (% increase in bulk density over a control sample) divided by (% treated pulp using the sample). Results are given in the following table:
TABLE V______________________________________Addition of Crosslinked Pulp into Tissue Furnish Tissue A Tissue BTreated Pulp Used Bulk, Bulk,in Furnish, % cm.sup.3 /g Efficiency cm.sup.3 /g Efficiency______________________________________ 0 4.0 -- 3.5 --10 4.5 1.2 4.9 3.720 5.4 1.7 5.8 3.140 7.7 2.3 8.4 3.060 11.2 3.0 13.0 4.5______________________________________
The effectiveness of the crosslinked pulp at increasing bulk is immediately apparent. It was unexpected that the bulking efficiency would increase as higher levels of crosslinked pulp were used.
EXAMPLE 7
In order to compare different cyclic urea compositions a supply of dihydroxyethyleneurea (DHEU) was prepared by reacting equimolar portions of glyoxal and urea, generally as taught in British Patent 717,287. This was compared with the Arotex 900 dimethyloldihydroxyethyleneurea (DMDHEU) used in the previous examples. Using 15% of each compound is respective treatment baths, samples were made up as described in Example 2. 30% of Arotex Accelerator 9 was used with the Arotex 900 in the treatment bath while 30% of a 10 g/L zinc nitrate solution was used with the DHEU. After drying, reaction times between the crosslinking agent and cellulose of 1-3 minutes were used at a temperature of 140° C. Table VI shows that nearly identical bulk values were obtained with the two compounds.
TABLE VI______________________________________ Handsheet Bulk Density cm.sup.3 /gReaction Time, min DMDHEU DHEU______________________________________1 25 243 28 295 26 25______________________________________
The two compounds appear to be about equally effective and there appears to be no advantage for using longer reaction times.
EXAMPLE 8
The following tests were made to show the effectiveness of other generic classes of chemical crosslinking agents for cellulose.
A 20 g (oven dried weight) sample of never dried Northwest bleached kraft softwood pulp at 35% consistency was weighed out and placed in a British Disintegrator, made up to 2 L with deionized water, and agitated for 5 min at 600 rpm. The reslurried fiber was then dumped into a 8"×8" (203×203 mm) Noble and Wood laboratory sheet mold containing 4 L of deionized water. More water was added up to 2" below the top of the mold to give a total of about 6.3 L. A perforated stainless steel plate somewhat less than the cross-sectional size of the sheet mold, with a 12" handle, was inserted into the sheet mold and moved up and down three times in rapid succession and 1 time slowly. The valve on the bottom of the sheet mold was opened and the stock drained through the screen. The pad of pulp remaining of the screen was removed, placed between synthetic fiber felts, and squeezed very gently through press rolls. The final weight of the pad was 65 g (45 g water and 20 g pulp).
A 1% solution of as received Berocell 541 (Berol Chemical Company, Reserve, La.) was made up and sprayed onto both sides of the pulp pad (approximately equal distribution) to obtain an uptake of 1% softener based on OD pulp. After 3 min a 15% solution of maleic anhydride (MA) in water was sprayed onto the pulp pad in the same manner for a 15% (based on OD pulp) material uptake. The pad was then placed between 2 dry 8"×8" pulp blotters and fed through the drum dryer until the pad was completely dry. It was then transferred to a watch glass and placed in a 160° C. oven for 15 minutes. A 3.5 g sample was torn off the pad and reslurried in the British Disintegrator (using 2 L of deionized water) for 5 min at 600 rpm. The slurry was passed into a 61/4" TAPPI sheet mold and processed to a hand sheet. The pad was drum dried without pressing, conditioned at 50% RH and 23° C., and measured for bulk density.
In the like manner, additional samples were treated with 1,2,3,4-butanetetracarboxylic acid (BTCA), 4,5-dihydroxy-1,3-dimethyl-2-imidazolidinone (DDI), with and without softener. The samples made with DDI included 1% (based on pulp) of a mixed AlCl 3 .MgCl 2 catalyst. All samples were run in duplicate. Results are given in Table VII. Sheet formation was graded relatively as follows:
1-uniform good formation
2-fairly good formation without nits (undispersed fiber clumps)
3-fair formation with some knots or flocs present
4-very poor formation with original sample not completely redispersed.
TABLE VII______________________________________Bulk Values Using Various Cellulose Crosslinking Agents Bulk Value RelativeTreatment cm.sup.3 /g Dispersibility______________________________________Untreated 4.90 21% softener 4.87 115% MA 5.38 315% MA + 1% Softener 6.51 115% DDI 5.82 215% DDI + 1% Softener 7.73 115% BTCA 6.3.sup.(1) 415% BTCA + 1% Softener 10.17 1______________________________________ .sup.(1) Best estimate attainable due to very poor formation
In all cases, except with glyoxal, the bulk value was improved when a softener was incorporated into the cellulose prior to addition and reaction of the crosslinking agent. Tests made under the other conditions have shown glyoxal to be an effective material in the application. All of the softened samples reslurried more readily than those without the softener.
EXAMPLE 9
The work described in Example 2 was repeated in order to make a fiber length measurement study on reslurried sheets. One difference this time was an increase in the concentration of Arotex 900 from 10% to 15% on an as received basis in the treatment bath. A second difference was the use of 0.5% Varisoft 727 as the debonding material. Varisoft is a registered trademark of Sherex Chemical Company, Dublin, Ohio. Verisoft 727 is a formulated alkyl diamidoamine type quaternary compound in which the alkyl substituents are typically oleyl or tallow based. The composition contains about 30% quaternary material.
The higher concentration used here, as compared with Example 2, would be expected to increase the ultimate concentration of the latent crosslinking material in the cellulose fiber from about 3.8% to 5.7% and also to increase the brittleness of the crosslinked fibers. Fiber length determinations were made using a Kajanni Type FS-100 automatic fiber length analyzer, available from Kajanni Electronics Co., Kajanni, Finland. As before, the samples were dispersed in the British Disintegrator until smooth, knot free slurries were attained. Results are given below.
TABLE VIII______________________________________ Control Crosslinked pulp (Un- No De- De- treated) bonder bonded______________________________________Disintegration Energy, revs 15,000 138,000 25,000Handsheet Bulk Density, cm.sup.3 /g 3.1 7.9 20.9Weighted Ave. Fiber Length, mm 3.0 1.3 2.4______________________________________
The debonded crosslinked pulp retained 80% of the fiber length of the control sample with very little more disintegration energy being required to redisperse the sheets in water. The crosslinked samples without debonder had only 43% of the average fiber length of the control samples. This major reduction is probably due to the very much higher energy required to obtain a smooth, knot-free fiber slurry.
EXAMPLE 10
A set of experiments was made to show the relative effectiveness of other types of quaternary debonding agents when used in conjunction with the Arotex 900 dimethylodihydroxyethyleneurea (DMDHEU) latent crosslinking agent. The type numbers listed below refer to those noted earlier in the description of preferred embodiments.
Variquat and Adogen are registered trademarks of Sherex Chemical Company. Variquat 638 is described as a methyl bis(2-hydroxyethyl) coco ammonium chloride having 74-75% quaternary material. Adogen 471 is a tallow trimethyl ammonium chloride with 49-52% quaternary material. Varisoft 222-90% is a methyl bis(tallow amidoethyl) 2-hydroxyethyl ammonium methyl sulfate with 89-91% solids. Quaker 2006 is an imidazoline type debonder available from Quaker Chemical Co., Conshohocken, Pa.
TABLE IX______________________________________Effect of Quaternary Debonder Type with DMDHEUCrosslinking Agent Disintegration Bulk Density, Type Energy, revs cm.sup.3 /g______________________________________Variquat 638.sup.(1) 1 125,000 10.5Adogen 471 1 30,000 14.6Varisoft 222-90% 2 30,000 19.9Varisoft 727 2 30,000 18.3Quaker 2006 4 30,000 19.5______________________________________ .sup.(1) This is a modified Type 1 material in that R.sub.2 and R.sub.3 are 2hydroxyethyl or polyoxyethanol.
Representatives of all the general types of quaternary debonders worked well, although the modified Type 1 material does not seen as effective under the conditions used as the other materials.
EXAMPLE 1
Nonionic and anionic material additives are not substantive to cellulose fibers in an aqueous slurry unless the electrical charge on the fiber surface is made more compatible. This is normally done by adding one of the class of papermaking chemicals generally called retention aids prior to the addition of the nonionic or anionic composition. These are most typically cationic materials that are substantive to the fibers and make the surface charge more positive. When anionic or nonionic debonders are used in the present invention they can be added at the wet end, prior to sheeting, or after the sheet is formed. When wet end addition is chosen a cationic retention aid is normally required. If a shower over the forming wire or press section, or a pad bath, is used the retention aid is normally not necessary since most of the debonder remains with the water entrapped in the sheet.
A series of experiments was made to show disintegration energy and bulk values with the two modes of addition using cationic, anionic and nonionic debonding agents. For the wet end addition of the nonionic and anionic materials, 0.5% (5 kg/t) of the retention aid Reten 210 was added to the fiber slurry prior to the addition of the debonder. Reten is a registered trademark of Hercules, Inc., Wilmington, Del., for a very high molecular weight polyacrylamide having approximately 2-4 mol% cationic sites. No retention aid was used with the cationic material. The cationic debonder was Varisoft 727, described in Example 10; the nonionic material was Triton X-100, described in Example 4; and the anionic was a sodium linear alkyl sulfonate composition with 26.8% active material obtained from Chemithon Corp., Seattle, Wash. These were all used in dosages of 5 kg/t of the as received material. Those samples in which the debonder and latent crosslinking agent were added after sheet formation were prepared according to the procedure of Example 4, with the two materials being mixed in the same treating solution. All samples were made using 15 kg/t as received of Arotex 900 crosslinking agent in the treating bath. Relative dispersibility was evaluated by the criteria set forth in Example 8, with the exception that here the samples were retained in the British Disintegrator for a sufficient number of revolutions to obtain a relatively smooth slurry. Results were as follows.
TABLE X______________________________________Point of Addition of Debonding Agent BulkDebonder Point Disintegration Density, RelativeClass Addition Energy, revs cm.sup.3 /g Dispersibility______________________________________Cationic Wet End 30,000 17.9 1 Pad Bath 30,000 18.3 1Nonionic Wet End 138,000 11.9 3 Pad Bath 62,500 16.9 2Anionic Wet End 175,000 11.0 3 Pad Bath 112,500 13.0 3______________________________________
Under the conditions of the present test the cationic debonder was the most efficient class of material. Pad bath addition was more efficient for the nonionic and anionic debonders than wet end addition. This may be due to an incompatibility or zeta potential unbalance between the particular type or concentration of retention aid and debonder. It is expected that with additional experimentation similar results would be obtained for wet end and pat bath addition. The particular anionic system chosen for these samples was not particularly efficient.
EXAMPLE 12
Wet tensile strength is believed to be one measure of the ease of reslurrying a sheeted material. An additional set of samples was made in similar fashion to those of Example 9. Wet tensile strength was measured on specimens taken from the Noble and Wood handsheets. Measurements were made using horizontal specimens 100 mm wide and 80 mm between grips, with a head speed of 1/3 mm/sec. Values were as noted in Table XI.
TABLE XI______________________________________Wet Tensile Strength Values Tensile Strength,Treatment kN/m______________________________________None 8Crosslinked, no softener 89Crosslinked, with softener 30______________________________________
The combination of softener with the crosslinked pulp reduced wet tensile strength to 1/3 of that without softener.
EXAMPLE 13
While some latent crosslinking reagents require additional heating at elevated temperatures after the sheet is normally dried, in order to effect reasonably complete reaction with the cellulose, others will react sufficiently under normal drying conditions. The use of urea nitrate as a catalyst for the urea-based latent crosslinking materials generally eliminates the need for post-drying heating. This material appears to be more active than the normally used inorganic salts or salt mixtures. Urea nitrate can be made with equimolar portions of urea and nitric acid under aqueous reaction conditions, using the method of Hebeish and Ibraham, Textile Res Jour., 52 (2):116-122 (1982).
A series of samples was made following the procedure of Example 5. Arotex 900 DMDHEC latent crosslinker was used in pad bath percentages varying between 2.5% and 20% with urea nitrate present in the bath equivalent to 3.3% of the DMDHEC, as calculated on a dry materials basis. Samples for testing were dried to about 4% moisture content without any additional post drying heating. The sample temperatures probably did not exceed about 90° C. at any time. Bulk densities and air resistance values age given in the following table.
TABLE XII______________________________________Bulk Density and Air Resistance of Low TemperatureCrosslinked SheetsAs Received Crosslinker Air ResistanceCrosslinker Solids Based Handsheet Bulk Pressure Drop,in Pad Bath, % on Pulp, % Density, cm.sup.3 /g mm______________________________________0 0 3.0 47.22.5 1.0 6.3 17.85.0 1.9 10.0 13.210.0 3.8 15.4 3.115.0 5.7 20.5 1.820.0 7.6 22.5 1.5______________________________________
Bulk and air resistance results are generally comparable with those reported in Table VI where a post drying reaction period of 1.5 minutes at 150° C. was used.
EXAMPLE 14
Urea nitrate was used as in the previous example as the catalyst for Arotex 900 DMDHEU latent crosslinker solution. The urea nitrate was made by dissolving 23.1 g of urea in 462 mL, of water. To this was added 33 mL of 70% nitric acid (containing 32.7 g HNO 3 ). A sufficient time was allowed for the reaction to go to completion. A solution was then made of 923 mL of as received Aerotex 900 in 4615 mL water. To this was added the above catalyst solution.
A bleached southern pine kraft pulp previously treated with a debonding agent and at about 5% moisture content was treated with the above solution on a basis of about 1 mL latent crosslinker solution per gram of pulp. The treated pulp was crosslinked in a drying oven. Samples of the untreated pulp, pulp immediately after the application of the crosslinking agent, and crosslinked pulp were slurried in distilled water and the pH measured immediately, after 10 minutes and after 25 minutes with the following results.
TABLE XIII______________________________________ pH Value After MixingSample <1 min 10 min 25 min______________________________________Untreated pulp 4.68 4.85 4.86Treated pulp, wet uncrosslinked 4.70 4.84 4.90Treated pulp, dried crosslinked 5.07 5.20 5.30______________________________________
It is evident that the pH of the system is not reduced below a value commonly experienced on a conventional paper machine.
EXAMPLE 16
In a test similar to the above, a solution of Aerotex 900 DMDMEC latent cross linking agent was mixed with Aerotex Accelerator 9 catalyst solution. As was noted earlier. This is a solution of acidic salts believed to be a mixture of aluminum and magnesium chlorides. Two parts of the Aerotex 900 were used with one part Accelerator 9 on a solids basis. The latent crosslinking solution was applied as above to a debonder treated bleached southern pine kraft similar to that of the previous example not from a different mill lot having higher initial pH. As above, pH was measured on the untreated pulp, the wet treated but uncrosslinked pulp, and the dried crosslinked pulp. The results are given in the following table.
TABLE XIV______________________________________ pH Value After MixingSample <1 min 10 min 25 min______________________________________Untreated pulp 6.40 5.77 6.42Treated pulp, wet uncrosslinked 4.22 4.25 4.20Treated pulp, dried crosslinked 4.05 4.30 4.25______________________________________
As before the pH of the system was above 4 at all times. This is a level quite compatible with modern papermaking practice.
It will be apparent to those skilled in the art that many departures can be made from the present description and examples while remaining within the spirit of the invention. The invention is to be considered as being limited only by the following claims. | The invention is a method of making a wet formed, sheeted, readily reslurriable sheeted crosslinked cellulose and the products made by the method. Crosslinked wood pulp fibers tend to be quite brittle. If crosslinked while in sheeted form, the sheets cannot be readily defibered, either in a wet or dry state, without serious fiber degradation. The sheet products of the present invention can be easily redispersed or repulped in water without significant fiber breakage. The present products are made by including within the sheet, while still in wet form, a debonding or softening agent which is preferably added before the latent crosslinking reactant. Most preferably the debonder is added prior to the headbox of a paper machine and the crosslinking reactant is applied near the end of the forming wire or at the press section. The treated sheet is dried conventionally. Crosslinking may occur entirely during drying or during a period of additional heating, usually at a temperature in excess of 100° C. for a short period of time. Conventional debonding agents and crosslinking reactants are suitable. The softening agent apparently reduces or prevents adhesive bonding between adjacent fibers caused by polymer formation external to the fiber under reaction conditions. | 0 |
Notice: This is a continuation reissue of application Ser. No. 10 / 074 , 012 , filed Feb. 14 , 2002 , which is a reissue application of U.S. Pat. No. 6 , 024 , 708 .
This is a continuation division of application Ser. No. 08/458,215, filed Jun. 2, 1995, now U.S. Pat. No. 5,666,965 which is a continuation of Ser. No. 07/837,046 filed Feb. 18, 1992, now U.S. Pat. No. 5,507,296, which is a continuation of Ser. No. 07/521,766 filed May. 10, 1990 now U.S. Pat. No. 5,133,727.
BACKGROUND OF THE INVENTION
This invention relates to biopsy forceps and more particularly to unique handler actuation wire and homologous jaw construction for those forceps.
A number of different types of biopsy forceps are in common use, typically in conjunction with endoscopic assistance. Ordinarily, these devices are of complicated construction, requiring the manufacturing and machining of precise miniaturized components, which are therefore generally quite expensive.
One early example of flexible forceps is shown in U.S. Pat. No. 3,895,636 (1975) to Schmidt, wherein a pair of cup shaped jaws having an annular rim mate with a hub and a sharpened trocar. The jaws in this embodiment are of a nature which requires machining for the edge, each jaw being different from the other jaw.
U.S. Pat. No. 4,887,612 to Esser et al, shows a similar biopsy forceps which utilizes a cam linkage to effectuate the cup shaped jaws toward and away form one another. The jaws shown in this patent are made from stainless steel and likewise, require expensive machining.
U.S. Pat. No. 4,763,668 to Macek et al, shows a biopsy forceps whose cup shaped forceps are driven by a linkage arrangement. Each pivot point in the linkage establishes a new place for stress, wear and breakage. This is similar to the linkage assembly shown in U.S. Pat. No. 4,721,116 to Schintgen et al. A needle between the forceps shown in this patent, is retractable as the forceps close.
U.S. Pat. No. 3,921,640 to Freeborn, shows a surgical instrument manufactured from a single piece of molded plastic. The instrument may have any of various forms of jaws including an arrangement of teeth for holding towels or surgical dressing.
U.S. Pat. No. 4,200,111 shows a pair of spring biased jaws which are slidably disposed within the end of a trocar. The jaws are moved inwardly and outwardly from the trocar by movement from a twisted wire.
U.S. Pat. No. 4,669,471 to Hayashi, shows a biopsy forceps device having a pair of cups attached by a pivot pin, with several linkages between the cups and the operating wire, which are likewise, connected by pivot pins, the pins being welded or fused to their components by the use of laser welding.
U.S. Pat. No. 4,815,460 to Porat et al, shows a medical device for gripping, having a pair of jaws which are identical to one another. The jaws have an array of teeth disposed completely thereacross. The teeth are divided longitudinally across each jaw and are out of phase from one another by a half a pitch. The instrument is utilized for gripping purposes. A further device is shown in U.S. Pat. No. 825,829 to Heath. This appliance utilizes two different sets of engaging jaws to accomplish its cutting purpose.
It is an object of the present invention to provide a forcep device which overcomes the disadvantages of the prior art.
It is a further object of the present invention to provide a cutting device having a pair of jaws, wherein each jaw may be a duplicate of its opposing jaw.
It is yet a further object of the present invention to provide a cutting device which is self-aligning which permits greater tolerance in the dimensions of the components in their manufacture.
SUMMARY OF THE INVENTION
The present invention comprises an improvement in biopsy forceps wherein a pair of jaws are formed from a casting. Each jaw of the pair of jaws of the biopsy forceps may be a duplicate of the other jaw. Each jaw is somewhat hemispherically shaped having an elongated portion which extends proximally into a cutter tang. Each cutter jaw has a generally U-shaped distalmost end on which is defined a plurality of radially disposed teeth. The teeth on one side of the longitudinal centerline of the jaw are displaced by one-half pitch from the corresponding teeth on the other side of the longitudinal centerline on that jaw. The displacement by one-half pitch of the teeth on one side of the jaw relative to those corresponding teeth on the other longitudinal side of the jaw permits the same casting to be used for both the upper and lower jaws. The radially disposed array of teeth on each of the jaws permits a self-aligning feature therewith, thus compensating for the slightly looser tolerances found in the casting manufacturing technique.
Each jaw extends proximally and terminates in a tang, as aforementioned. Each tang is arranged so as to receive a joggled pull wire therethrough. Each jaw is mated with one another about a clevis pin which is cast unitarily with a clevis. The clevis extends into a housing which is crimped to a main coil, the proximal end of which extends into a handle having means for articulating the jaws. Each joggled pullwire from the tang on the proximal end of each jaw flexibly extends through the main coil and into the hub of the handle at the proximal end of the forceps assembly.
The handle comprises a central shaft about which a displaceable spool is disposed. The central shaft has a longitudinally directed stepped diameter bore extending therein on its distal end, and a thumb ring on its proximalmost end. The proximal end of the coil extends into the bore on the proximal end of the central shaft. The bore in the central shaft on the handle has a stepped configuration. The distal end of the bore having a slightly larger diameter than the second or intermediate bore, or the third or proximal end of the bore in the central shaft. A locking coil is arranged to mate within the stepped large outer diameter (distal end) of the central shaft. The locking coil has an inner diameter which is slightly smaller than the outer diameter of the main coil extending from the cutter jaw assembly to the handle. The main coil is screwed into the locking coil disposed within the central shaft. A sheath which acts as a strain relief, is disposed distally of the locking coil about the main coil within the central shaft. The sheath holds the locking coil within the first stepped bore in the central shaft. The strain relief is bonded to the bore of the central shaft. The proximalmost end of the joggled pull wires extend through the proximal end of the main coil and into a thin anti-kink tube in the narrowest third stepped bore in the central shaft. The cross pin fits through a slot at the midpoint of the central shaft. The slot is in communication with the third bore therein. A cross pin mates with the slot across the central shaft. The proximalmost end of the joggled pull wires are locked into an opening in the cross pin. The ends of the cross pin mate with slots in the spool so as to facilitate corresponding motion in the joggled pull wires.
Proximal movement of the spool with respect to the central shaft effectuates a pull on the joggled pull wires so as to create a pivotable motion of the tangs on the proximal end of the cutters, to cause the cutter jaws to engage to one another.
Movement of the spool distally with respect to the central shaft effectuates a compression on the pull wire thus causing arcuate movement of the tangs on the proximal end of each jaw to force a pivoting motion about the clevis pin thus opening the respective jaws.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of the present invention will become more apparent when viewed in conjunction with the following drawings, in which:
FIG. 1 is a side elevational view in section, of a biopsy forceps assembly;
FIG. 2 is a side assembly view of the distalmost end of a biopsy forceps assembly with a needle, with its cutter jaws being opened;
FIG. 3 is a plan view, partly in section, of the distal end of a biopsy forceps without a needle;
FIG. 4 is a side elevational view partly in section of the biopsy forceps shown in FIG. 3 with its jaws opened;
FIG. 5 is a plan view, partly in section, of the distal end of a biopsy forceps assembly, with a needle;
FIG. 6 is a side elevational view partly in section, of the biopsy forceps shown in FIG. 5 ; and
FIG. 7 is a side elevational view in section, showing part of the handle at the proximalmost end of a biopsy forceps assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in detail and particularly to FIG. 1 , there is shown a biopsy forceps assembly 10 , having a distal end 12 , comprising a jaw assembly 14 , and a proximal end 16 comprising a handle 17 , spool 19 and thumb ring 21 for manipulation of the assembly. The jaw assembly 14 comprises a pair of jaws 18 , each of which is a duplicate of the other. Each jaw 18 as may be seen in FIGS. 2 and 3 , is a generally elongated somewhat hemispherically shaped structure having a distalmost end and a proximalmost end. Each jaw 18 has on its distalmost end, an array of teeth 20 generally radially directed about a point “R”, as exemplified in FIG. 3 . Each jaw 18 has a generally longitudinal centerline as may be seen in FIGS. 3 and 5 . The teeth 20 on one side of the longitudinal centerline of each jaw 18 being displaced by one half pitch from the corresponding teeth 20 on the other side of the longitudinal centerline on that jaw 18 . The displacement by one half pitch by the teeth on one side of the jaw 18 is relative to those corresponding teeth 20 on the other longitudinal side of the jaw 18 permits the same casting to be used for both the upper and lower jaws of the jaw assembly 14 . The radial arrangement of the teeth 20 as best seen in FIGS. 3 and 5 require each jaw 18 when they close onto one another to automatically mate and effectuate proper alignment therebetween. The self-alignment permits each jaw 18 to be manufactured by an investment casting technique which is inheritantly less expensive than the typical prior art jaws which are machined and which distalmost teeth are either non-existant or they are transverse to the longitudinal centerline the jaws, which jaws inheritantly fail to have any positive cutting edge at their distalmost ends. The casting of each jaw 18 also permits a looser tolerance therebetween which is characteristic of the casting manufacturing technique without any loss in effectiveness of those jaws.
Each jaw 18 has a proximalmost end which comprises a tang 24 . Each tang 24 has a generally semicircular recess position 26 on its outer side thereof. The recessed portion 26 may be seen most clearly in FIGS. 3 and 5 , and then a side view in FIGS. 2 , 4 and 6 . A bore 30 extends tranversely through the midpoint between the distal end proximalmost ends of each jaw 18 . Each jaw 18 is mated with one another and so as to each be levered about a clevis pin 28 which extends through the bore 30 on each respective jaw 18 . Each jaw 18 has an annular bore 33 disposed about the outer face of its bore 30 , as shown in FIGS. 3 and 5 . The boss 33 acts as a bearing surface to reduce the typical friction found on prior art forceps. The clevis pin 28 is received in a hole 32 in clevis 34 as shown in FIGS. 3 and 5 . The clevis 34 extends proximally, as shown in FIGS. 2-6 , into a hub 40 . The clevis 34 , the housing 40 and clevis pin 28 are made from a common casting. The clevis pin 28 unitarily extending from one of the sidearms 29 Of the clevis 34 .
A main tubular coil 50 shown in FIG. 2 at its distal end thereof, has a portion of it periphery ground flat, as at 52 . The flattened distal periphery of the main coil 50 permits a more solid anchoring between the inside of the hub 40 and the distal end of the main coil 50 when the two are crimped together, obviating the need for adhesives, soldering or welding.
An FEP sheath 54 extends from the distal end of the main coil 50 therethrough into the central shaft 56 of the handle 17 as shown in FIGS. 2 and 7 . This sheath 54 acts as a bearing between a pair of pull wires 60 and the lumen of the main coil 50 .
The distalmost end of each pull wire 60 has a Z-bend therein. the Z-bend of each pull wire 60 has a first portion 62 which is rotatably disposed in the recess 26 in the tang 24 of each cutter jaw 18 . The Z-bend has a second portion 64 which extends through a bore 66 in the proximalmost end of the tang 24 , as best shown in FIGS. 3 and 5 . A ninety degree bend 68 between the second portion 64 and the main pull wire 60 eliminates the pinching common to prior art loop design wires. Each pull wire 60 has a reflex curve 70 as shown in FIG. 2 as well as in FIGS. 6 and 7 , extending between their distalmost ends and the distalmost end of the main coil 50 . The reflex curve 70 helps to open the cutter jaws 18 when the spool 19 on the handle 17 is displaced distally thereto.
FIGS. 2 , 5 and 6 shows the distal end of the biopsy forceps assembly 10 with a flat needle 80 disposed between the two cutter jaws 18 . The needle 80 has a pointed distalmost end 82 that terminates just within the cutter jaws 18 when closed, and has tail 84 comprising its proximalmost end which extends within the distalmost end of the main coil 50 . The needle 80 has a central opening through which the clevis pin 28 may extend as shown in FIGS. 3 and 5 . The needle 80 is flat, and as such may be disposed between the two tangs 24 of each cutter jaw 18 as shown in FIG. 5 . In cutter jaw assembly 14 without the needle therein, a washer 90 is disposed between the two cutter jaws 18 on the clevis pin 28 .
The proximal end of the main coil 50 and the proximal end of the pull wires 60 extend into handle 17 at the proximal end 16 of the biopsy forceps assembly 10 . The handle 17 comprises a central shaft about which a displaceable spool 19 is disposed. The central shaft has a longitudinally directed stepped diameter bore 92 extending therein, as shown in FIGS. 1 and 7 . The proximal end of the main coil 50 extends into the bore 92 on the proximal end of the central shaft. The bore 92 extending into the central shaft has a three stepped configuration. The bore 92 on the distalmost end of the central shaft has a large first diameter 94 as shown in FIG. 7 which steps to a smaller second diameter 96 which subsequently steps down to a smaller yet third diameter bore 98 . A locking coil 100 is disposed against the first largest diameter bore 94 in the central shaft. The main coil 50 has an outer diameter slightly larger than the inner diameter of the locking coil 100 and is threadedly received therethrough. The main coil 50 thus extends to and abuts the handle 17 adjacent the second stepped bore 96 of the bore 92 in the central shaft. The pull wires 60 disposed through the inner lumen of the main coil extend therethrough and into the smallest portion 98 of the bore 92 in the central shaft. A strain relief sheath 102 is disposed distally to the locking coil about the main coil 50 within the largest bore 94 in the central shaft. The strain relief sheath 102 extends slightly distally of the distalmost end of the central shaft, and is bonded to the inner walls of the largest bore 94 by a solvent which is directed thereto through a hole 104 , as shown in FIG. 7 . The strain relief sheath 102 limits twist and movement of the main coil 50 with the bore 94 while preventing a sharp bend of the coil 50 at the distal end of the handle 17 . The proximalmost end of the pull wires 60 extend through the proximal end of the main coil 50 as aforementioned and through and anti-kicking tube 109 , and are locked into a cross pin 110 , as shown in FIG. 1 , which cross pin 110 mates with a slot 112 disposed across the central shaft of the handle 17 . The slot 112 is in communication with the axial bore 92 in the central shaft. The proximalmost end of the pull wires 60 are locked into the cross pin 110 by a set screw 114 as shown in FIG. 1 . The ends of the cross pins 110 mate with a slot 116 in the spool so as to lock the cross pin 110 therewith. Movement of the spool 19 which is disposed about the central shaft thereby effectuates movement of the puller wires 60 disposed within the main coil 50 , the distal ends of which are attached to the tangs 24 on the cutter jaws 18 as shown in FIGS. 1 and 2 .
Thus there has been shown a biopsy forceps assembly which can be made in a very cost effective manner for an improved biopsy sample. The cutter jaws and clevis support of the biopsy forceps each being made of a cast material permitting a far less expensive manufacture because of its simplicity permitting one jaw design and its self-aligning radially directed distal jaw teeth effectuating its cutting effectiveness as well as its ease of assembly. The pull wire arrangement with each particular jaw eliminates the prior art multiple linkages which have frictional problems and potential for breakage therewith. The spool design for the grasping of the pull wires in regard to the handle therewithin facilitates a one-handed operation thus permitting the physician use of his other hand for other purposes. | A biological forceps device for the taking of tissue samples from a body, comprising a flexible main coil attached at its distal end to a pair of homologous cast jaws. The jaws have radially arranged teeth on their distalmost end. The jaws are opened and closed by attachment to a pair of pull wires which extend through the main coil, into a handle at its proximal end, the handle has a spool which slides about a central shaft attached to the main coil. The spool is attached to the pull wires, so that movement of the spool with respect to the central shaft, effectuates a force on the proximal ends of the levered jaws, to open and close them, appropriately. | 0 |
CROSS REFERENCE TO OTHER PATENT APPLICATIONS
This application is a divisional application and claims the benefit of the filing date of U.S. patent application Ser. No. 14/280,889; filed on May 19, 2014; and entitled “Twin-Axial Wire Antenna” by the inventor, David A. Tonn.
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention is directed to a linear antenna for dual frequencies and a method for designing such an antenna and more particularly to a twin-axial floating antenna that can be deployed from a vessel.
(2) Description of the Prior Art
Previous work on buoyant cable antenna (BCA) improvements have led to antennas that have improved performance in the HF band (e.g., U.S. Pat. No. 7,868,833 entitled “Ultra wideband buoyant cable antenna element”) but this improvement came at the expense of the performance of the antenna in the VLF/LF band (10 kHz-200 kHz. This occurred because the methods involved required the use of series capacitive loading along the length of the antenna wire. This creates a high pass filter in the antenna and prevents current flow in the VLF/LF bands.
U.S. Pat. No. 8,203,495, entitled “Modular VLF/LF and HF buoyant cable antenna and method” introduces a useful method of including the VLF/LF capability back into the antenna. In this patent, the VLF/LF signals are received on the braid of a piece of coaxial cable that is connected in series with the loaded HF antenna. However, this method suffers from two major shortfalls. The first is that the attenuation of the coaxial cable hinders the gain of the HF antenna, since HF signals must pass through the coaxial cable to reach the overall antenna feed point. The second is that the overall antenna length increases to over 150 feet long, which is undesirable from a mechanical point of view since it affects the speed-depth curves and hinders the submarine's operations when using the antenna.
SUMMARY OF THE INVENTION
It is a first object of the present invention to provide an antenna capable of operating in both HF/VHF and VLF/LF bands;
Another object is to provide such an antenna having good performance in the HF band while not sacrificing performance in the VLF band; and
Yet another object is to provide an antenna having a shorter length than known with series arrangements.
Accordingly, there is provided an antenna that includes a polymer coating having a VLF/LF element and an HF/VHF element embedded therein. A blocking choke is interposed between the VLF/LF element and the antenna feed to block HF/VHF signals. Small chokes are regularly positioned on the VLF/LF element to suppress resonances in the HF/VHF bands caused by mutual capacitance between the elements. Reactive loads are positioned in said HF/VHF element at regular intervals for optimizing performance of the antenna in the HF/VHF radio bands. In further embodiments the antenna is provided as a floating antenna with the elements helically arranged therein.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference is made to the accompanying drawings in which are shown an illustrative embodiment of the invention, wherein corresponding reference characters indicate corresponding parts, and wherein:
FIG. 1 is a cross-sectional view of an antenna;
FIG. 2 is a diagram of a typical antenna;
FIG. 3 is a view of a section of an antenna; and
FIG. 4 is graph showing normalized performance gains of the current antenna over a prior art antenna.
DETAILED DESCRIPTION OF THE INVENTION
This invention combines the functionality of the two legacy buoyant cable antenna elements into a single antenna element while also providing for improved gain in the high frequency (HF, between 3 MHz and 30 MHz) and very high frequency (VHF, between 30 MHz and 300 kHz) radio bands to support improved communications for submerged submarines.
An embodiment shown in FIGS. 1 and 2 overcomes limitations found in the prior art by utilizing a twin-axial geometry. As shown in FIG. 1 , this antenna 10 employs two center conductors, a VLF conductor 12 and an HF conductor 14 , instead of one in the prior art. The antenna 10 has a cylindrical geometry with a circular cross section of constant diameter d maintained over the length, l, of the antenna. Conductors 12 and 14 are embedded in a body 16 made from any polymer foam. The polymer foam should be positively buoyant in seawater, electrically insulating, chemical resistant and durable in normal seawater temperatures. Many different polymer foams are suitable for this purpose.
Antenna conductors 12 and 14 are embedded into body 16 and arranged so that their centroid is coincident with the axis 18 of the antenna over its entire length. The conductors 12 and 14 are, therefore, positioned on either side of the center 18 of antenna body 16 , as shown in FIG. 1 . The conductors 12 and 14 can be arranged parallel to one another or can be positioned helically at a constant pitch angle. In either embodiment, the spacing between the conductors, b, is constant along the entire length of the antenna 10 . In one embodiment, the HF conductor 12 and the VLF conductor 14 each have the same gauge and are made from stranded conductors. In alternate embodiments, the two conductors 12 and 14 can be of differing gauges and can be either stranded or solid. In a prototype, both conductors were made from #22 solid copper wire arranged parallel to each other within a body 16 .
Each of the conductors 12 and 14 carries signals from a separate portion of the radio spectrum. An antenna feed 20 is located at the proximate end of each conductor and is electrically joined to radio equipment (not shown). The VLF conductor 12 carries VLF/LF signals. At its distal end, VLF conductor 12 connects to environmental ocean water by means of a grounding ring 22 . Grounding ring 22 is a short-circuit termination electrically connected to environmental water which is assumed to be at ground potential. The HF conductor 14 carries signals in the HF/VHF band and terminates at its distal end in an open circuit termination 24 prior to the end of the antenna 10 . In another embodiment, open circuit termination 24 can terminate at the end of the antenna 10 . Open circuit termination 24 cannot electrically connect to grounding ring 22 . This is necessary for maximum gain in the HF band.
To provide optimal HF/VHF performance, the HF conductor 14 is provided with a reactive load 26 at regular intervals along its length, dz 1 . Reactive load 26 can be made from a single capacitor, a single capacitor and a single inductor connected in parallel, or a combination of these types of reactive loads. Reactive loads 26 are inserted in series with the HF conductor 14 . In some embodiments, parallel capacitor inductor reactive loads can be used for one portion of the HF conductor 14 , while the remainder of the HF conductor 14 uses capacitors alone. The capacitor and inductor are selected so as to optimize the performance of the antenna in the HF and VHF bands. In the prototype, single capacitors having a capacitance of 680 pF were used, with the distance between reactive loads, dz 1 , being 1 meter apart.
The VLF conductor 12 connects to the HF conductor 14 at antenna feed 20 through a blocking choke 28 . Blocking choke 28 is preferably a ferrite core shielded inductor chosen to keep applied signals in the HF and VHF bands from passing into the VLF/LF conductor 12 .
Due to the mutual capacitance between the VLF conductor 12 and HF conductor 14 , HF and VHF signals can couple from the HF conductor 14 onto the VLF conductor 12 and cause VLF conductor 12 to resonate. The resonance of the VLF conductor 12 can affect the gain and impedance of the HF conductor 14 detrimentally. This resonance is suppressed by electrically interrupting the VLF conductor 12 at regular intervals by providing small chokes 30 at locations in conductor 12 . Small choke 30 is chosen so that its impedance is high enough to stop the flow of current on the VLF conductor 12 but no so high as to impede the flow of current in the VLF/LF bands. The spacing between adjacent small chokes 30 , dz 2 , was chosen to be smaller than one-half of the shortest wavelength in the band or bands of operation of the HF conductor 14 . In this way, the segments of the VLF conductor 12 interconnecting chokes 30 are sub-resonant. In the prototype, blocking choke 28 had a value of 22 μH, and small chokes 30 all had a value of 1 μH.
FIG. 3 shows a preferred embodiment of the invention, where the two wires are arranged as a twisted pair of constant pitch angle. FIG. 3 , with the reactive loads 26 placed periodically along the HF/VHF wire 14 and the small chokes 30 placed repeatedly along the VLF/LF wire 12 , with the entire assembly centered within a polymer foam jacket 16 . Polymer foam jacket 16 is provided with hidden lines to show VLF/LF wire 12 and HF/VHF wire 14 within. While reactive loads 26 and chokes 36 should be positioned periodically on wire 14 and wire 12 , the placement period is not required to be the same for each wire 14 and 12 .
FIG. 4 shows the measured normalized HF gain performance of the first working model compared with the gain of a legacy BCA element. HF gain performance line 40 shows the gain of the first working model, and HF gain performance line 42 shows the gain of the legacy element. Improved gain performance of up to 5 dB is noted in the region from 8-17 MHz. VLF performance was measured at 24 kHz using the station at Cutler, Me. as a beacon. The measurement showed performance comparable to a legacy BCA. (Note that due to the nature of VLF propagation, measurements across the band are not possible and so performance is measured using signals from fixed stations.)
It will be understood that many additional changes in the details, materials, steps and arrangement of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.
The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description only. It is not intended to be exhaustive, nor to limit the invention to the precise form disclosed; and obviously, many modification and variations are possible in light of the above teaching. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims. | An antenna includes a polymer coating having a VLF/LF element and an HF/VHF element embedded therein. A blocking choke is interposed between the VLF/LF element and the antenna feed t block HF/VHF signals. Small chokes are regularly positioned on the VLF/LF element to eliminate resonances caused by mutual capacitance between the elements. Reactive loads are positioned in said HF/VHF element at regular intervals for optimizing performance of the antenna in the HF/VHF radio bands. In further embodiments the antenna is provided as a floating antenna with the elements helically arranged therein. | 7 |
RELATED APPLICATION
[0001] This application claims the benefit of the filing date of U.S. Provisional Application No. 60/481,805, filed Dec. 17, 2003, the entire disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a breathing aid for a person. In particular, the invention relates to an oxygen supply system, which is preferably small and light enough to be portable, as would be desirable for use by a patient, for example, for home use.
SUMMARY OF THE INVENTION
[0003] According to one embodiment, a portable oxygen supply for home use is provided. The supply includes, for example, an electrolyzer for generating oxygen from water in response to electric power input, and a fuel cell connected with the electrolyzer for providing electric power to the electrolyzer and water. According to another embodiment, a method of providing oxygen for home use is presented. The method includes, for example, the steps of: generating electricity in a fuel cell; providing electricity from the fuel cell to an oxygen source to operate the oxygen source to produce oxygen; and directing the oxygen from the oxygen source to a patient device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a schematic illustration of an oxygen supply system in accordance with one embodiment of the invention;
[0005] FIG. 2 is a schematic illustration of an oxygen supply that forms part of the oxygen supply system of FIG. 1 ;
[0006] FIG. 3 is a schematic illustration of one embodiment of an oxygen generator that can be used in the oxygen supply system of FIG. 1 ;
[0007] FIG. 4 is a schematic illustration of a direct methanol fuel cell that can be used as the power source of FIG. 2 ;
[0008] FIG. 5 is a schematic illustration of the operation of a methanol fuel cell system that is one embodiment of the invention; and
[0009] FIG. 6 is a schematic illustration of a hydrogen fuel cell system that is another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0010] One embodiment of the present invention relates to a breathing aid for a person; for example, an oxygen supply system for home use that is preferably small and light enough to be portable. The invention is applicable to oxygen supply systems of various different types and constructions. As representative of one embodiment of the invention, FIG. 1 illustrates schematically an oxygen supply system 10 . The system 10 includes an oxygen supply 12 that is also an embodiment of the invention. In one embodiment, the system 10 may be of the type shown in U.S. Pat. No. 5,988,165, the entire disclosure of which is hereby incorporated by reference.
[0011] The oxygen supply 12 is operable to provide oxygen-enriched gas for use in the system 10 . The oxygen-enriched gas in the illustrated embodiment is fed to a product tank 14 . In other embodiments, the product tank 14 can be omitted. A 5-psi regulator 16 emits oxygen-enriched gas from the product tank 14 into a flow line 18 and feeds the same to a flow meter 20 which subsequently emits the oxygen-enriched gas to the patient at a predetermined flow rate of from 0.1 to 6 liters per minute. Optionally, the flow meter 20 can be closed so that all the oxygen-enriched gas is directed to a compressor 21 .
[0012] Gas not directed to the patient is carried via line 22 to two-way valve 24 . A very small portion of the gas in the flow line 20 is directed through a line 26 and a restrictor 28 into an oxygen sensor 30 which detects whether or not the concentration of the oxygen is of a predetermined value, for example, at least 50 percent.
[0013] When the oxygen sensor 30 detects a concentration at or above the predetermined level, the two-way valve 24 is kept open to permit the oxygen-enriched gas to flow through the valve 24 and a line 32 into a buffer tank 34 wherein the pressure is essentially the same as the pressure in the product tank 14 . However, should the oxygen sensor 30 not detect a suitable oxygen concentration, two-way valve 24 is closed so that the oxygen concentrator 12 can build up a sufficient oxygen concentration. This arrangement prioritizes the flow of oxygen-enriched gas so that the patient is assured of receiving a gas having a minimum oxygen concentration therein. In other embodiments, prioritization may be omitted.
[0014] The buffer tank 34 can have a regulator 36 thereon generally set at approximately 12 psi to admit the oxygen-enriched gas to the compressor 21 when needed. The output of the compressor 21 is used to fill a cylinder or portable tank 38 for ambulatory use by the patient. Alternatively, the pressure regulator 36 can be set at anywhere from about 13 to about 21 psi. A restrictor 39 controls the flow rate of gas from the buffer tank 34 to the compressor 21 . Should the operation of the compressor 21 cause the pressure in the buffer tank 34 to drop below a predetermined value, a pressure sensor (not shown) automatically cuts off the flow of gas at a pressure above the pressure of the gas being fed to the patient. This prioritization assures that the patient receives priority with regard to oxygen-enriched gas.
[0015] In accordance with one embodiment, the oxygen supply 12 is preferably configured and constructed so as to be small, light weight, and self-contained—that is, portable and/or transportable. The oxygen supply 12 is shown schematically in FIG. 2 as including an oxygen source 40 and a power source 42 . Various different types of oxygen sources 40 may be used.
[0016] The oxygen source 40 , shown schematically in FIG. 2 , is preferably, although not necessarily, an electrolyzer, that is, a device that generates oxygen by splitting water through the application of electricity. At least two different types of electrolyzers are possible. One type of electrolyzer does not generate hydrogen, while the other type does produce hydrogen as a by-product. Other types of oxygen sources are described below.
[0017] In one embodiment, the oxygen source 40 includes a proton exchange medium between the electrodes. Feed water is electrolyzed at the anode to produce oxygen, hydrogen ions and electrons. The hydrogen ions are then combined with oxygen in the ambient air to produce water. The oxygen source 40 thus converts water and air into oxygen, air and water.
[0018] In another embodiment, the oxygen source 40 is of the known type of electrolyzer that produces hydrogen gas in addition to one or more other by-products.
[0019] The oxygen from the oxygen source 40 can be collected, treated, pressurized, etc., in any one of numerous known manners. One example is shown in FIG. 3 , which illustrates schematically one embodiment of operation of an oxygen concentrator 50 that uses an electrochemical stack or electrolysis cell 52 , as one example of an oxygen source 40 , to electrolyze water to produce oxygen, without producing hydrogen.
[0020] In this embodiment, concentrator 50 includes a water/oxygen separator 54 , a water/air separator 56 , an air source 58 , and a power supply 60 . Optionally, the oxygen concentrating system 50 may include one or more condensers 62 and one or more ion-exchange beds 64 .
[0021] The oxygen from the stack 52 can be separated into a patient-grade oxygen-rich stream (oxygen, or oxygen-enriched gas) 66 . This can be accomplished by delivering the oxygen product stream 68 from the electrolysis cell 52 to the oxygen-water separator 54 . The water collects at the bottom of the oxygen-water separator reservoir 54 , while the oxygen collects in the top portion of the reservoir until it can be bled off for patient use. One advantage of this arrangement is that the oxygen-rich stream 66 that is provided to the patient is saturated with water vapor. If the oxygen stream 100 is too dry, the nasal membrane of the patient might be irritated and possibly damaged. In other embodiments, humidification can be omitted.
[0022] The air product stream 70 from the electrolysis cell 52 can be separated in the water-air separator 56 to form a spent air stream 72 and a water stream 74 . The spent air 72 can be vented to atmosphere, while the water stream 74 can be fed into the oxygen-water separator 20 and then recycled through the system as feed to the electrolysis cell.
[0023] A concentrator of this type, or of another type as used in the oxygen supply 12 , may include a number of warning and detection systems. For example, an oxygen concentration sensor can be placed in the system to determine whether sufficient oxygen purity is being produced. A warning system, either visual or audio, can be used when the oxygen concentration falls below a predetermined value. The oxygen concentration sensor can also be used to trigger a system shut-down if the oxygen concentration falls below a predetermined value for a determined time period.
[0024] Impurities in the feed water to the electrolysis cell 40 or 52 may impair the functionality of the cell. Deionized or distilled water can be used in order to produce effective functionality of the electrolysis cell 50 . Optionally, an ion exchange bed 64 , or other filtration means, can be used in the system to filter out impurities in the feed water. The filtration mechanism can be used solely as a precautionary means, in that it will effectively remove trace amounts of impurities in the deionized feed water and allow for some use of non-deionized water in the system. Alternatively, the filtration mechanism can be larger, or replaceable, thereby allowing use of tap water on a regular basis.
[0025] Water level detection systems can also be used to ensure sufficient amounts of water are available to the system 50 , most notably in the water/oxygen separator 54 . For example, water can collect in the water/air separator 56 until a predetermined amount of water is collected. Once the predetermined amount of water is collected, a drain valve 78 can be opened to allow the water to be delivered to the water/oxygen separator 54 , and subsequently as recycled water feed 80 to the electrolysis cell 52 . A warning system can be used when the water level in the system falls below a predetermined critical operational level. The warning system can be one or two stages. In a one stage system, a warning signal will be triggered when the water level in the system falls below the predetermined level. This warning signal can be visual or audio. The two stage system can include a similar warning signal at a first predetermined level and then commence a system shut-down at a second predetermined level. In other embodiments, the system shut-down can occur after a predetermined time period following the actuation of the warning signal.
[0026] As noted above, different types of oxygen sources 40 can be provided. In place of the electrolysis cell and concentrator, the system could include a pressure swing concentrator, for example, that provides oxygen (or oxygen-enriched gas) from ambient air without electrolyzing water.
[0027] The oxygen supply 12 also includes a source of electric power 42 for the oxygen source 40 . The power source 42 can be any conventional means of providing power, such as, for example, a battery, a generator, or an electrical connection to a power line in a house.
[0028] In one embodiment, power source 42 is a fuel cell that generates electricity used to power the oxygen source 40 . Different types of fuel cells 42 can be used. One type of fuel cell 42 is a direct methanol fuel cell. Another type of fuel cell 42 is a hydrogen fuel cell.
[0029] FIG. 4 illustrates schematically the operation of one embodiment of a direct methanol fuel cell 82 . The fuel cell 82 includes an anode 84 and a cathode 86 . The fuel cell 82 is powered solely by methanol. A fuel cell 82 of this type can be sized to generate any level of desired power output, for example, 400 watts, enough to run an oxygen source 40 with the desired output.
[0030] A mixture of water and methanol is fed into the fuel cell 82 on the anode side 84 . The molecules are electrolyzed to produce carbon dioxide and hydrogen ions. The hydrogen ions traverse the cell and are combined with air on the cathode side 86 to produce water. The carbon dioxide, and any non-electrolyzed water and methanol, are the products on the anode side 84 of the cell, and form a methanol/water product stream 88 .
[0031] FIG. 5 illustrates one embodiment of a system 100 that combines a methanol fuel cell 82 and an electrolysis cell 52 . An air supply 102 feeds air to both the fuel cell 82 and the electrolysis cell 52 . Water from water supply 104 feeds the electrolysis cell 52 and combines with methanol from methanol supply 106 to feed the fuel cell 82 . The fuel cell 82 supplies power to the electrolysis cell 52 .
[0032] The products from the electrolysis cell 52 are an oxygen/water stream 110 and an air/water stream 112 . The oxygen/water stream 110 is separated into an oxygen stream 114 and a water stream 116 . The oxygen stream 114 can be fed to a patient or stored for subsequent use. Water stream 116 can be recycled to water supply 104 .
[0033] The air/water stream 112 is separated into an air stream 118 and a water stream 120 . The air stream 118 can be vented to atmosphere, while the water stream 120 can combine with water stream 116 for recycling to the water supply 104 .
[0034] The fuel cell 82 produces a methanol/water/carbon dioxide stream 88 and an air/water/carbon dioxide stream 124 . The methanol/water/carbon dioxide stream 88 can be fed into a separator 126 , wherein any excess air or carbon dioxide is vented in stream 128 , while the methanol and water are returned to the methanol/water feed stream 130 via stream 132 . The air/water/carbon dioxide stream 124 is separated into air stream 134 and water stream 136 . The air stream 134 can be vented to atmosphere, while the water stream 136 is recycled to the water supply 104 .
[0035] The combination of the methanol fuel cell 82 and the oxygen concentrator electrolysis cell 52 can provide for an efficient and portable system that can generate patient-grade oxygen for prolonged periods of time. The patient grade oxygen supply can be used in the home or it can be used for individual use when in transit. The air water separator for the fuel cell and the oxygen concentrator can be combined, thereby making the system more compact. In addition, only one water level need be maintained. The water product of the fuel cell can also be used as a portion of the feed to the oxygen concentrating electrolysis cell, thereby requiring less water to be added to the system on a regular basis.
[0036] One embodiment of a hydrogen fuel cell is shown schematically at 140 in FIG. 6 . A hydrogen fuel cell 140 uses hydrogen as an input fuel and also has an air input. If the oxygen source 142 is an electrolyzer as in the embodiment of FIG. 7 , it produces hydrogen 144 as a by-product. This excess hydrogen 144 can be recycled into the hydrogen fuel cell 140 . This avoids venting hydrogen to the atmosphere. The electrolyzer 142 may require external power, as shown in FIG. 7 , in addition to the power provided by the fuel cell.
[0037] In addition, for any type of fuel cell that produces water 146 as a by-product, this water can be recycled into the electrolyzer to meet its demand for water.
[0038] While the present invention is disclosed through various embodiments, descriptions, and illustrations, further embodiments and modifications based on this disclosure are also possible. For example, fuel cell technology based on other sources and types of input fuels can also be used. Electrolyzers of different physical construction and material composition can also be employed. Therefore, the invention in its broader aspects is not limited to the specific embodiments, illustrations, and descriptions presented herein. | A portable oxygen supply for home use may include an electrolyzer for generating oxygen from water in response to electric power input, and a fuel cell electrically connected with the electrolyzer for providing electric power to the electrolyzer. A method of providing oxygen for home use may include the steps of generating electricity in a fuel cell; providing electricity from the fuel cell to an oxygen source to operate the oxygen source to produce oxygen; and directing the oxygen from the oxygen source to a patient device. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a division of copending Application Ser. No. 333,497, filed Feb. 20, 1973, now U.S. Pat. No. 3,935,214; issued Jan. 27, 1976, and entitled 2- OR 3-KETO-C-PHENYL-1,4-DISUBSTITUTED PIPERAZINES, said application Ser. No. 333,497 in turn being a continuation-in-part application of copending Application Ser. No. 848,395, filed July 23, 1969, and entitled 1,4-DISUBSTITUTED PHENYL PIPERAZINE COMPOUNDS, COMPOSITIONS CONTAINING SAME, AND PROCESS OF MAKING AND USING SAME, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to new and valuable phenyl piperazine compounds and more particularly to 1,4-substituted phenyl piperazine compounds of noteworthy therapeutic utility and to a process of making and using same.
2. Description of the Prior Art
ARCHER in U.S. Pat. No. 3,062,821 discloses 1,4-disubstituted-2-piperazinones of Formula I ##STR1## In said formula R represents lower alkyl;
X and X' represent hydrogen, lower alkoxy, or hydroxyl; and
Y hydrogen or lower alkyl.
Said 1-[2-(phenyl lower alkyl)]-4-lower alkyl-2-piperazinone compounds are useful intermediates in the preparation of compounds of Formula II ##STR2## in which R, X, X', and Y represent the same substituents as given hereinabove. These 1-[2-(phenyl lower alkyl)]-4-lower alkyl piperazine compounds are useful hypotensive agents.
DE BENNEVILLE in U.S. Pat. No. 3,390,139 discloses N-vinyl-2-piperazinones of Formula III ##STR3## in which R 1 is hydrogen, alkyl, cycloalkyl, aralkyl, alkyl substituted aralkyl, diaminoalkyl, or furfuryl;
R 2 is hydrogen or methyl;
R 3 is hydrogen, alkyl, cycloalkyl, phenyl, naphthyl, alkyl, chloro, or alkoxy substituted phenyl or naphthyl, aralkyl, alkyl substituted aralkyl, or 2-furyl;
R 4 is hydrogen or alkyl; and
R 5 is hydrogen or alkyl.
These compounds are polymerizable or copolymerizable compounds, the resulting polymers or copolymers are useful for many purposes. Higher members of the monomeric N-vinyl-2-piperazinones of Formula III show fungistatic and bacteriostatic activity and are useful for other purposes.
DE BENNEVILLE in U.S. Pat. No. 2,653,153 describes 4-N-substituted-2-ketopiperazines of Formula IV ##STR4## in which R is alkyl, tertiary aminoalkyl, or aralkyl; and
R' and R" are hydrogen or lower alkyl. These 4-N-substituted-2-ketopiperazines are valuable activators and synergists for insecticidal agents.
None of these compounds has found any noteworthy application in veterinary and human therapy.
SUMMARY OF THE INVENTION
It is one object of the present invention to provide valuable 1,4-substituted phenyl piperazine compounds which have a surprising and pronounced effect upon blood coagulation and are useful, for instance, in the treatment of thrombotic diseases, especially those of the arterial system.
Another object of the present invention is to provide a simple and effective process of producing such valuable novel 1,4-substituted phenyl piperazine compounds.
A further object of the present invention is to provide pharmaceutical compositions containing, as active pharmaceutical agent, said novel 1,4-substituted phenyl piperazine compounds
Still another object of the present invention is to provide a method of therapeutically affecting blood coagulation by administering the novel 1,4-substituted phenyl piperazine compounds.
Other objects of the present invention and advantageous features thereof will become apparent as the description proceeds.
In principle, the new 1,4-substituted phenyl piperazine compounds according to the present invention correspond to the following formula V ##STR5## In said formula X, Y, and Z are the same or different substituents and may be either hydrogen, halogen, trifluoro lower alkyl, preferably trifluoro methyl, hydroxyl, lower alkoxy, preferably methoxy or ethoxy, or phenyl substituted lower alkoxy, such as benzyloxy;
R is di-(lower)alkylamino (lower)alkyl, and preferably dimethylamino ethyl, diethylamino ethyl, dipropylamino ethyl, dimethylamino propyl, diethylamino propyl, di-n-propylamino propyl, or lower alkyl substituted by one or two saturated monocyclic heterocyclic rings such as piperidino, pyrrolidino, piperazino, N-lower alkyl piperazino, 3-ketopiperazino, morpholino, or the like, preferably piperidino ethyl, morpholino ethyl, or dimorpholino propyl;
R 1 is lower alkyl with 1 to 3 carbon atoms; and ##STR6## is the group ##STR7##
The term "lower alkyl" in said substituents indicates alkyl with 1 to 5 carbon atoms. Thus the substituent in N 1 -position of the piperazine ring may be benzyl, phenyl ethyl, or phenyl propyl, or substituted benzyl, phenyl ethyl, phenyl propyl. Preferred substituents in the N 1 -aralkyl group are
One halogen atom in 2-; 3-; or 4-position.
Two halogen atoms in 2,3-; 2,4-; 2,5-; or 3,4- position and, if desired, also in 2,6-position.
Such halogen substituted compounds may also carry hydroxyl or lower alkoxy, preferably methoxy groups.
One lower alkoxy group, preferably one methoxy or ethoxy group in 4-position.
Three lower alkoxy groups, preferably in 3,4,5-position.
One phenyl lower alkoxy group, preferably the benzyloxy group in 2- or 4-position.
Two phenyl lower alkoxy groups, preferably the benzyloxy groups in 3,4-position.
Two hydroxyl groups, preferably in 2,3, and/or 4-position.
One trifluoro lower alkyl group, preferably the trifluoromethyl group in 3-position. addition
The phenyl radical in position 2 or 3 of the piperazine ring is always unsubstituted.
The basic lower alkylamino group in N 4 -position is preferably a group of the Formula VI ##STR8## in which R 2 is lower alkyl;
R 3 is hydrogen or a saturated five- or six-membered heterocyclic ring, preferably the morpholino ring attached by its heterocyclic nitrogen atom to the lower alkyl R 2 ; and
R 4 and R 5 are lower alkyl or, together with the nitrogen atom to which they are attached, form a saturated five- or six-membered heterocyclic ring, such as the pyrrolidino, piperidino, piperazino, or morpholino ring. The piperazino ring may be substituted at its other nitrogen atom by lower alkyl or by hydroxy lower alkyl to represent the N 4 -lower alkyl or N 4 -hydroxy lower alkyl piperazino ring or it may be substituted by a keto group to represent the 3-keto piperazino ring.
It is evident that the compounds according to the present invention represent two groups of compounds, namely
a. The N 1 -phenyl lower alkyl substituted 2- or 3-phenyl substituted N 4 -basically substituted 3- or 2-piperazone compounds of Formulas VII or VIII: ##STR9## and b. the N 1 -phenyl lower alkyl substituted 2- or 3-phenyl substituted N 4 -basically substituted piperazine compounds of Formulas IX and X: ##STR10##
In said Formulas VII to X the symbols R 1 , R 2 , R 3 , R 4 , R 5 , X, Y, and Z represent the same substituents as indicated hereinabove.
Especially valuable compounds according to the present invention are compounds of the following Formula XI and XII: ##STR11## In said Formulas X 1 is hydrogen or lower alkoxy.
Y 1 and Z 1 are hydrogen, halogen, trifluoromethyl; hydroxyl, lower alkoxy, and phenyl lower alkoxy, whereby X 1 is lower alkoxy only if Y 1 and Z 1 are lower alkoxy;
R 1 is lower alkyl with 1 to 3 carbon atoms;
R 2 is lower alkyl;
R 3 is hydrogen or a saturated five- or six-membered heterocyclic ring, said heterocyclic ring being attached by its heterocyclic nitrogen atom to the lower alkyl R 2 ;
R 4 and R 5 are lower alkyl or, together with the nitrogen atom to which they are attached, form a saturated five- or six-membered heterocyclic ring.
According to the present invention the 1,4-substituted phenyl piperazine compounds of the above given Formulas have a pronounced effect upon the blood coagulation system. They act upon all processes which play an essential role in the formation of thromboses, such as their coagulation promoting effect due to their power of releasing the thrombocyte factor 3, their coagulation inhibiting effect, and their trombocytes aggregation and adhesion inhibiting effect. Thus the novel compounds of the present invention or their pharmaceutically acceptable acid addition salts are highly effective anticoagulants. They prolong the clotting time of blood on oral or parenteral administration of the required dose and have been found to inhibit platelet aggregation, such as induced by the addition of adenosine diphosphate, when added to platelet-rich plasma.
The compounds according to the present invention can be administered for their anticoagulant effect over a wide dosage area. For instance, a dosage of about 0.5 mg./kg. to 100 mg./kg. of body weight orally administered daily or on parenteral administration has proved to be highly effective.
The new compounds according to the present invention may find particular application in the treatment of thrombotic disease, especially of the arterial system, for instance, to inhibit thrombosis of the coronary or cerebral arteries.
The following new piperazine compounds according to the present invention have been found to be useful in therapy:
1-(4-chloro benzyl)-2-phenyl-4-(diethylamino ethyl)piperazine
1-(3,4-dichloro benzyl)-2-phenyl-4-(diethylamino ethyl)piperazine;
1-[(4-methoxy phenyl)-ethyl]-2-phenyl-4-(diethylaminoethyl)-piperazine;
1-[3-phenyl propyl-(1)]-2-phenyl-4-(diethylamino ethyl)-piperazine;
1-(4-chloro benzyl)-2-phenyl-4-(piperidino ethyl) piperazine;
1-(4-chloro benzyl)-2-phenyl-4-[1,3-dimorpholino propyl-(2)]piperazine;
1-(4-chloro benzyl)-3-phenyl-4-(diethylamino ethyl) piperazine.
The new piperazine compounds of the above given Formulas are obtained according to the present invention, for instance, by reacting a 1-R-substituted phenyl piperazine of Formula XIII. ##STR12## wherein ##STR13## and R represent the above given groups and substituents, with an aralkyl halogenide of Formula XIV ##STR14## wherein X, Y, Z, and R 1 represent the same substituents and numerals as given hereinabove, while
Hal is halogen.
Another method of producing the 1,4-substituted phenyl piperazine compounds according to the present invention comprises reacting a 1-aralkyl phenyl piperazine of Formula XV. ##STR15## wherein ##STR16## X, Y, Z, and R 1 represent the above given substituents, with a basically substituted alkyl halogenide of Formula XVI ##STR17## wherein
Hal is halogen and R represents the above given substituent.
A further method of producing the 1,4-substituted phenyl piperazine compounds according to the present invention comprises reacting a 1-aralkyl phenyl piperazine, substituted in the ω-position by a reactive group Q, preferably by a halogen atom, and having the general Formula XVII ##STR18## wherein ##STR19## X, Y, Z, and R 1 have the above given meaning, and R 6 is lower alkyl, with a corresponding secondary amine of the group consisting of a di-lower alkyl amine, such as dimethylamine, diethylamine, dipropylamine, or with piperidine, morpholine, pyrrolidine, piperazine, 3-ketopiperazine, or a lower N-alkyl piperazine.
If desired, the keto group in the resulting reaction product of Formula V, wherein ##STR20## is either ##STR21## is reduced to the methylene group, so as to yield compounds of Formula V wherein ##STR22## represents either ##STR23##
The resulting basically substituted phenyl piperazine compounds of Formula V may be converted, if desired, into their substantially non-toxic, pharmaceutically acceptable acid addition salts by methods well known to the art. Not only physiologically tolerable salt-forming inorganic acids, such hydrochloric acid, sulfuric acid, phosphoric acid, hydrobromic acid, and others, but also organic acids, such as acetic acid, propionic acid, benzoic acid, salicyclic acid, succinic acid, malonic acid, citric acid, tartaric acid, fumaric acid, and others can be used in the preparation of therapeutically valuable salts.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following examples serve to illustrate the present invention without, however, limiting the same thereto.
EXAMPLE 1
1-(4'-Chloro benzyl)-2-phenyl-4-(diethylamino ethyl) piperazine ##STR24## Method A:
1-(4'-Chloro benzyl)-2-phenyl piperazine
44 g. of 1-(4'-chloro benzyl)-2-phenyl-3-keto piperazine obtained according to Example 1, Method A (a) of Application Ser. No. 333,497, are dissolved in 350 cc. of dioxane. The solution is added drop by drop to a suspension of 15 g. of lithium aluminum hydride LiAlH 4 in 800 cc. of ether while stirring thoroughly. After addition is completed, the reaction mixture is boiled under reflux for 12 hours. Thereafter, the lithium complex compound is decomposed and excess lithium aluminum hydride is destroyed by successively treating the reaction mixture with 15 cc. of a 15% sodium hydroxide solution, with 15 cc. of water, with 45 cc. of a 15% sodium hydroxide solution, and with 30 cc. of water. The inorganic precipitate is removed by filtration and the filtered solution is evaporated to dryness. The residue is recrystallized from isopropanol. 37 g. of pure white crystals of the melting point 103°-104° C. are obtained.
Method B:
1-(4'-Chloro benzyl)-2-phenyl piperazine
142.4 g. of 1(4'-chloro benzyl)-2-phenyl-3-keto piperazine prepared according to Example 1, Method A (a) of Application Ser. No. 333,497, are suspended in 400 cc. of benzene while stirring vigorously. 800 cc. of a 1.5 molar solution of dibutyl aluminum hydride are then allowed to run slowly to said suspension. Thereby the reaction mixture is caused to boil under reflux. Half an hour after the addition is completed, the mixture is cooled to 5° C. Excess dibutyl aluminum hydride is decomposed by careful addition of water. The precipitated aluminum hydroxide is dissolved in 40% sodium hydroxide solution. The separated organic layer is washed with 40% sodium hydroxide solution and then with water and is freed of its organic solvent by evaporation. The residue is recystallized from 1.5 l. of isopropanol.
Pure white crystals of the melting point 103°-104° C. are obtained in a yield corresponding to the theoretical yield. The resulting compound is identical with the compound obtained according to Method A given hereinabove as is proved by chromatography and infrared spectroscopy.
b. 1-(4'-Chloro benzyl)-2-phenyl-4-(diethylamino ethyl) piperazine
30 g. of the base prepared according to Methods A or B as described hereinabove are dissolved in 100 cc. of toluene. The solution is boiled under reflux with 20 g. of diethylamino ethylchloride and 20 g. of finely pulverized anhydrous potassium carbonate for 8 hours. By treating the reaction mixture with water, separating the toluene layer, extracting the base with hydrochloric acid, setting the base free from its hydrochloride solution by addition of ammonia, and dissolving it in benzene, the base is purified. After distilling off the solvent and repeated distillation in a vacuum, 34 g. of a yellow oil of the boiling point 188°-199° C./0.09 mm. Hg are obtained. Yield: 81% of the theoretical yield.
EXAMPLE 2
1-(3',4'-Dichloro benzyl)-2-phenyl-4-(diethylamino ethyl) piperazine ##STR25##
a. 1-(3',4'-Dichloro benzyl)-2-phenyl-3-keto piperazine
140 g. of 2-phenyl-3-keto piperazine are boiled under reflux with 163 g. of 3,4-dichloro benzylchloride in 1,600 cc. of acetone for 6 hours while 330 cc. of triethylamine are added. The hot reaction mixture is filtered to remove precipitated triethyl ammonium chloride and is concentrated by fractional distillation. The resulting crystal fractions are twice recrystallized from 4 l. of 96% ethanol.
162 g. of the above given reaction product of the melting point 195°-208° C. (with decomposition) are obtained. Yield: 52% of the theoretical yield.
b. 1-(3',4'-Dichloro benzyl)-2-phenyl piperazine
132 g. of the keto piperazine prepared as described hereinabove under (a) are dissolved in 200 cc. of dioxane. Said solution is added drop by drop to a suspension of 21 g. of lithium aluminia hydride LiAlH 4 in 900 cc. of absolute ether while the suspension is exposed to vibration. After the addition is completed, the mixture is boiled under reflux for 12 hours. Successively 20 cc. of 15% sodium hydroxide solution, 20 cc. of water, 60 cc. of 15% sodium hydroxide solution, and 40 cc. of water are added to the reaction mixture to cause decomposition of the complex compound formed. The filtrate is freed of solvent, the residue is distilled, and a viscous oil, boiling between 170° C./0.02 Torr. and 178° C./0.02 Torr., is obtained. The oil crystallizes on trituration with heptane. It is twice recrystallized from heptane. Yield: 110 g. corresponding to 87% of the theoretical yield.
c. 1-(3',4'-Dichloro benzyl)-2-phenyl-4-diethylamino ethyl) piperazine
40 g. of the piperazine compound prepared according to the method described hereinabove under (b), are boiled under reflux with 18.5 g. of diethylamino ethylchloride in 250 cc. of acetone with the addition of 52 cc. of triethylamine for 12 hours. The triethyl ammonium-chloride formed thereby is filtered off. The resulting solution is concentrated by evaporation. Absolute ethanolic hydrochloric acid is added to the residue. The precipitated hydrochloride is washed with ethanol and is dissolved in water. The base is set free from its aqueous solution by the addition of ammonia and is extracted by means of benzene. After drying over anhydrous potassium carbonate and removing the solvent, 34 g. of a light yellow oil of the boiling point 192° C./0.03 mm. Hg are obtained. The yield is 65% of the theoretical yield.
EXAMPLE 3
1-[(4'-Methoxy phenyl) ethyl]-2-phenyl-4-(diethylamino ethyl) piperazine ##STR26##
a. 1-[(4'-Methoxy phenyl)ethyl]-2-phenyl-3-keto piperazine
140 g. of 2-phenyl-3-keto piperazine, 148.5 g. of 4-methoxy phenyl ethylchloride, and 330 cc. of triethylamine in 1.6 l. of acetone are boiled under reflux for 12 hours. The acetone is distilled off. 300 cc. of dimethylformamide are added to the residue and the mixture is heated on the water bath for 36 hours. The major part of the dimethylformamide is distilled off in a vacuum. About 500 cc. of acetone and 150 cc. of triethylamine are added to the residue. The mixture is freed of triethylammoniumchloride by filtration while still boiling, and is cooled. After again distilling off the solvent, the remaining crystals are washed with petroleum ether and are triturated with water. The resulting solution is again filtered. On rendering the solution alkaline, the reaction product is precipitated initially in oily form. It crystallizes very rapidly. After recrystallizing the crystals three times from isopropanol pure white crystals of the melting point 142°-147° C. (with decomposition) are obtained. The yield is 110 g. corresponding to 44.7 % of the theoretical yield.
When carrying out the reaction from the beginning on in a mixture of dimethylformamide and triethylamine, the yield is lower than when proceeding as described hereinabove. This is due to formylation reaction taking place thereby.
b. 1-[(4'-Methoxyphenyl)-ethyl]-2-phenyl piperazine
29 g. of the keto piperazine prepared as described hereinabove under (a), are dissolved in 200 cc. of absolute dioxane. A suspension of 8 g. of lithium aluminum hydride LiAlH 4 in 700 cc. of absolute ether is added drop by drop to said solution while stirring vigorously. Thereafter, the mixture is boiled under reflux for 12 hours. After decomposing the reaction mixture by successive addition of 10 cc. of 15 % sodium hydroxide solution, 10 cc. of water, 30 cc. of 15 % sodium hydroxide solution, and finally of 20 cc. of water in the order given, the mixture is freed from the precipitated inorganic salts by filtration and the filtrate is concentrated by evaporation. Ethanolic hydrochloric acid is added to the residue and the hydrochloride precipitated thereby is filtered off by suction. The base is set free from the hydrochloride by the addition of sodium hydroxide solution. 23 g. of a viscous oil are obtained. The oil crystallizes after standing for some time. It has a boiling point of 180°-185° C./0.01 mm. Hg. The yield is 83 % of the theoretical yield.
c. 1-[(4'-Methoxy phenyl)-ethyl]-2-phenyl-4-(diethylamino ethyl) piperazine
18 g. of the base obtained as described hereinabove under (b) are boiled under reflux with 30 g. of triethylamine and 12 g. of diethylamino ethylchloride in 120 cc. of acetone for 15 hours. The reaction solution is cooled, filtered, and freed of the solvent by concentration by evaporation. The residue is dissolved in dilute hydrochloric acid. The base is set free from its hydrochloride solution by the addition of ammonia, is extracted with benzene, and the benzene extract is again freed of its solvent. A mixture of acetone in ethanolic hydrochloric acid is added to the residue. The precipitated hydrochloride is filtered off by suction. The base is again set free from its hydrochloride by the addition of ammonia and is distilled in a vacuum. 17 g. of a viscous oil of the boiling point 215° C./0.002 mm. Hg are obtained. The yield is 70 % of the theoretical yield.
EXAMPLE 4
1-[3'-Phenyl propyl-(1)]-2-phenyl-4-(diethylamino ethyl) piperazine ##STR27##
a. 1-[3'-Phenyl propyl-(1)]-2-phenyl-3-keto piperazine
140 g. of 2-phenyl-3-keto-piperazine and 135 g. of 3-phenyl propylchloride(1) are heated on the water bath in 350 cc. of dimethylformamide with the addition of 330 cc. of triethylamine for 48 hours. The major portion of the dimethylformamide and the triethylamine are distilled off in a vacuum. The residue is dissolved in 2 l. of acetone. 150 cc. of triethylamine are added to said acetone solution. The mixture is boiled under reflux for 10 minutes. The solution is then cooled to 30° C. and is freed from triethyl ammoniumchloride by filtration. The keto-piperazine crystallizes from the resulting filtrate on cooling in a mixture of ice and sodium chloride. The crystals are purified by recrystallization from isopropanol and 50 % ethanol. 110 g. of white crystals of the melting point 114°-116° C. are obtained. The yield is 47 % of the theoretical yield.
b. 1-[3'-Phenyl propyl-(1)]-2-phenyl piperazine
43 g. of the keto-piperazine obtained as described hereinabove under (a) are dissolved in 200 cc. of dioxane and are reduced by the addition of 10 g. of lithium aluminum hydride LiAlH 4 suspended in 800 cc. of ether as described in the preceding examples. After decomposing the reaction mixture and recovering the base by purification via its hydrochloride, 30 g. of a viscous oil of the boiling point 155°-160° C./0.01 mm. Hg are obtained. The yield is 73 % of the theoretical yield.
c. 1-[3'-Phenyl propyl-(1)]-2-phenyl-4-(diethylamino ethyl) piperazine
23 g. of the base prepared as described hereinabove under (b) are boiled under reflux with 13.5 g. of diethylamino ethylchloride, 35 cc. of triethylamine, and 150 cc. of acetone for 10 hours. After recovering the base as described in the preceding examples and purifying it via its hydrochloride, 22 g. of a colorless oil of the boiling point 187°-189° C./0.01 mm. Hg are obtained. The yield is 70.5 % of the theoretical yield.
EXAMPLE 5
1-(4'-Chloro benzyl)-2-phenyl-4-(piperidino ethyl) piperazine ##STR28##
31 g. of 1-(4'-chloro benzyl)-2-phenyl piperazine prepared according to Example B), 25 g. of piperidino ethylchloride, 20 g. of triethylamine, and 250 cc. of acetone are boiled under reflux for 18 hours. The filtered reaction solution is freed of its solvent by concentration by evaporation. The residue is dissolved in benzene. The benzene solution is washed with water. After drying and distilling off the solvent, the base is obtained in the form of a viscous, yellow oil on distillation at 210° C./0.06 Torr. The oil crystallizes on trituration with isopropanol. After twice recystallizing the crystals from n-heptane (41 g. of yellow crystals of the melting point 85°-87° C.) are obtained. The yield is 95 % of the theoretical yield.
In place of acetone there may also be used other solvents, for instance, benzene, toluene, or xylene and, in place of triethylamine, for instance, pyridine, dimethylaniline, potassium carbonate, sodium amide or sodium hydride.
In a similar manner as described in Example 6 are obtained:
1-(4'-Chloro benzyl)-2-phenyl-4-pyrrolidino ethyl) piperazine, boiling point 200°-205° C./0.05 mm. Hg; melting point of the hydrochloride 254°-258° C. (decomposition), by reaction of 1-(4'-chloro benzyl)-2-phenyl piperazine and pyrrolidino ethyl chloride.
1-(4'-Chloro benzyl)-2-phenyl-4-[4'-methyl piperazino ethyl-(1)]piperazine, boiling point 215°-217° C./0.005 mm. Hg; melting point of the hydrochloride 252°-270° C. (decomposition), by reaction of 1-(4'-chloro benzyl)-2-phenyl piperazine and 1-(3-chloro ethyl)-4-methyl piperazine.
EXAMPLE 6
1-(4'-Chloro benzyl)-2-phenyl-4-[1",3"-dimorpholino propyl(2")]-piperazine ##STR29##
31 g. of 1-(4'-chloro benzyl)-2-phenyl piperazine prepared according to Example B, 52 g. of 1,3-dimorpholino propylchloride-(2), prepared by chlorinating 1,3-dimorpholino propanol-(2), 25 g. of triethylamine, and 250 cc. of acetone are boiled under reflux for 48 hours. The base remaining after filtration and evaporation of the solvent is purified by dissolving it in hydrochloric acid and setting it free from its hydrochloride solution by the addition of ammonia. The base is dissolved in benzene, and the benzene solution dried over anhydrous potassium carbonate. After distilling off the solvent, the residue is distilled in a vacuum of 0.1 Torr. The first fraction distilling over at a temperature up to 110° C. consists mainly of unreacted dimorpholino propylchloride. The remaining residue is dissolved in petroleum ether and is separated from undissolved matter by filtration after cooling. The solvent is distilled off and the remaining compound is purified by distillation in a vacuum. 34 g. of an oil of the boiling point 230° C./0.001 mm. Hg are obtained. The oil solidifies on standing.
EXAMPLE 7
1-(4'-Chloro benzyl)-3-phenyl-4-(diethylamino ethyl) piperazine ##STR30##
a. 1-(Diethylamino ethyl)-2-phenyl piperazine
1-(Diethylamino ethyl)-2-phenyl-3-keto piperazine is prepared by reacting N 1 -(diethylamino ethyl) ethylenediamine with α-chloro phenyl acetylchloride and isolating the above mentioned reaction product from the resulting mixture of isomers.
89 g. of said keto piperazine dissolved in 200 cc. of dioxane are added drop by drop to a suspension of 20 g. of lithium aluminum hydride LiAlH 4 in 800 cc. of ether. After addition of the keto piperazine, the reaction mixture is boiled under reflux for 6 hours. It is then decomposed by successively adding 20 cc. of 15% sodium hydroxide, 20 cc. of water, 60 cc. of 15% sodium hydroxide solution, and finally 40 cc. of water. The filtered solution is concentrated by evaporation and the residue is distilled in a vacuum. The resulting oil which distills at a temperature between 102° C. and 115° C./0.05 mm. Hg, is dissolved in benzene and is extracted therefrom by shaking in 10 % hydrochloric acid. The base is set free from its hydrochloride solution by the addition of 10 % sodium hydroxide solution and is repeatedly distilled in a vacuum. An almost colorless oil of the boiling point 114°-117° C./0.07 mm. Hg is obtained. The yield corresponds to the theoretical yield. The compound contains a small amount of 3-phenyl-1-(diethylamino ethyl) piperazine.
b. 1-(4'-Chloro benzyl)-3-phenyl-4-diethylamino ethyl) piperazine
26 g. of the base prepared as described hereinabove under (a) are boiled under reflux with 17.7 g. of 4-chloro benzylchloride and 42 cc. of triethylamine in 200 cc. of acetone for 10 hours. After filtration and distilling off the solvent, the base is purified in the manner described hereinabove via its hydrochloride and is set free from said hydrochloride by the addition of ammonia. The residue is freed of the solvent and is dissolved in acetic acid ethyl ester. The hydrochloride is precipitated from said solution by the addition of absolute ethanolic hydrochloric acid. The hydrochloride is recrystallized from acetic acid ethyl ester. The base is set free from said hydrochloride by means of ammonia and is distilled in a vacuum. An almost colorless oil of the boiling point 180° C./0.01 mm. Hg is obtained. The yield is 30 g. corresponding to 78 % of the theoretical yield.
This compound can be distinguished by means of its infrared spectrum from the isomeric 1-(4'-chloro benzyl)-2-phenyl-4-(diethylamino ethyl) piperazine by directly comparing both compounds.
EXAMPLE 8
1-(Diethylamino ethyl)-2-phenyl-4-(p-ethoxy benzyl) piperazine ##STR31##
(a) 1-Diethylamino ethyl-2-phenyl-3-keto piperazine
144 g. of 2-phenyl-3-keto piperazine are boiled under reflux with 121 g. of diethylamino ethylchloride, 340 cc. of triethylamine, and 1600 cc. of acetone for 24 hours. The cooled solution is filtered to remove triethylamine hydrochloride and the filtrate is evaporated to dryness. The residue is dissolved in water, 40 % sodium hydroxide solution is added thereto, and the oil which forms as upper layer, is extracted with benzene. The benzene solution is dried over anhydrous potassium carbonate, the benzene is removed by distillation, and the residue is distilled in a vacuum. A light yellow, viscous oil of the boiling point 175° C./0.05 mm. Hg is obtained. The oil is twice recrystallized from n-heptane. 145 g. of the above mentioned compound melting at 53°-56° C. are obtained. The yield is 64 % of the theoretical yield.
b. 1-Diethylamino ethyl-2-phenyl piperazine
89 g. of the keto piperazine prepared as described hereinabove under (a), are dissolved in 200 cc. of absolute dioxane. The solution is added to a suspension of 20 g. of lithium aluminum hydride LiAlH 4 in 800 cc. of absolute ether while exposing the mixture to vibration. After addition of the keto piperazine solution is completed, the reaction mixture is boiled under reflux for 6 hours. Thereafter it is decomposed by successive treatment with 21 cc. of 15 % sodium hydroxide solution, 21 cc. of water, 63 cc. of 15 % sodium hydroxide solution, and 42 cc. of water. The decomposed reaction mixture is filtered, the solvent is removed by distillation, and the residue is distilled in a vacuum. 65 g. of a light yellow oil of the boiling point 114°-117° C./0.05 mm. Hg are obtained. This oil corresponds to the above given compound. The yield is 77 % of the theoretical yield.
c. 1-Diethylamino ethyl-2-phenyl-4-(p-ethoxy benzyl) piperazine
40 g. of the piperazine derivative prepared as described hereinabove under (b) are boiled under reflux with 27 g. of p-ethoxy benzylchloride in 400 cc. of acetone with the addition of 50 cc. of triethylamine for 12 hours. The triethyl ammonium hydrochloride formed thereby is filtered off. The acetone is removed by distillation. The residue is dissolved in benzene and the base is dissolved therefrom in the form of its hydrochloride by extraction with dilute hydrochloric acid. The base is set free from its hydrochloride solution by the addition of ammonia and is extracted with benzene. The benzene solution is dried over anhydrous potassium carbonate. The solvent is distilled off and the residue is distilled in a vacuum. 39 g. of a light yellow viscous oil of the boiling point 200° C/0.05 mm. Hg are obtained. The yield is 64 % of the theoretical yield.
EXAMPLE 9
1-Diethylamino ethyl-3-phenyl piperazine
1-Diethylamino ethyl-2-keto-3-phenyl piperazine prepared according to Example 1 B (a) of application Ser. No. 333,497, is reduced by following the procedure described hereinabove in Example 7 (a) whereby, in place of 1-diethylamino ethyl-3-keto-2-phenyl piperazine, the equimolecular amount of said 1-diethylamino ethyl-2-keto-3-phenyl piperazine is reduced. The resulting 3-phenyl piperazine compound is obtained in the form of a light yellow oil boiling at 102° C./0.02 mm. Hg.
EXAMPLE 10
1-Benzyloxy benzyl-2-phenyl piperazine
1-Benzyloxy benzyl-2-phenyl-3-keto piperazine prepared according to Example 12, is reduced by following the procedure described hereinabove in Example 8 (a) whereby, in place of 1-diethylamino ethyl-3-keto-2-phenyl piperazine, the equimolecular amount of said 1-benzyloxy benzyl-2-phenyl-3-keto piperazine is used. The resulting 2-phenyl piperazine compound is obtained in the form of white crystals melting at 140-141° C.
EXAMPLE 11
1-(3',4',5'-Trimethoxy benzyl)-2-phenyl piperazine
1-(3',4',5'-Trimethoxy benzyl)-2-phenyl-3-keto piperazine prepared according to Example 13, is reduced by following the procedure described hereinabove in Example 8 (a) whereby, in place of 1-diethylamino ethyl-3-keto-2-phenyl piperazine, the equimolecular amount of said 1-(3',4',5'-trimethoxy benzyl-2-phenyl-3-keto piperazine is used. The resulting 2-phenyl piperazine compound is obtained in the form of a yellow oil boiling at 185-195° C./0.08 mm. Hg.
EXAMPLE 12
1-[3'-(4"-Methoxy phenyl) propyl(1) ]-2-phenyl piperazine
1-[3'-(4"-Methoxy phenyl) propyl(1)]-2-phenyl-3-keto piperazine prepared according to Example 14, is reduced by following the procedure described hereinabove in Example 8 (a) whereby, in place of 1-diethylamino ethyl-3-keto-2-phenyl piperazine, the equimolecular amount of said 1-[3'-(4"-methoxy phenyl) propyl(1)]-2-phenyl-3-keto piperazine is used. The resulting 2-phenyl piperazine is obtained in the form of a light yellow oil boiling at 176° C./0.05 mm. Hg.
EXAMPLE 13
1-(4'-Chloro benzyl)-3-phenyl-4-diethylamino ethyl piperazine
1-(4'-Chloro benzyl)-2-keto-3-phenyl-4-diethylamino ethyl piperazine prepared according to Example 10, is reduced by following the procedure described hereinabove in Example 8 (a) whereby, in place of 1-diethylamino ethyl-3-keto-2-phenyl piperazine, the equimolecular amount of said 1-(4'-Chloro benzyl)-2-keto-3-phenyl-4-diethylamino ethyl piperazine is used. The resulting 3-phenyl piperazine compound is obtained in the form of a light yellow oil boiling at 180° C./0.01 mm. Hg.
EXAMPLE 14
1-(3',4'-Dichloro benzyl)-2-phenyl-4-dimethylamino ethyl piperazine
1-(3',4'-Dichloro benzyl)-2-phenyl piperazine prepared according to Example 3 (b), is alkylated by following the procedure described in Example 3 (c), whereby, in place of the diethylamino ethylchloride, the equimolecular amount of dimethylamino ethylchloride is used. The resulting reaction product is obtained in the form of a light yellow oil boiling at 190° C./0.01 mm. Hg.
EXAMPLE 15
1-(3',4'-Dichloro benzyl)-2-phenyl-4-morpholino ethyl piperazine
1-(3',4'-Dichloro benzyl)-2-phenyl piperazine prepared according to Example 3 (b), is akylated by following the procedure described in Example 3 (c) whereby, in place of diethylamino ethylchloride, the equimolecular amount of morpholino ethylchloride is used. The resulting reaction product is obtained in the form of a light yellow oil boiling at 230° C./0.04 mm. Hg.
EXAMPLE 16
1-(3',4'-Dichloro benzyl)-2-phenyl-4-diethylamino propyl piperazine
1-(3',4'-Dichloro benzyl)-2-phenyl piperazine prepared according to Example 2 (b), is alkylated by following the procedure described in Example 2 (c) whereby, in place of the diethylamino ethylchloride, the equimolecular amount of diethylamino propylchloride is used. The resulting reaction product is obtained in the form of a light yellow oil boiling at 210° C./0.04 mm. Hg.
EXAMPLE 17
1-(4'-Benzyloxy benzyl)-2-phenyl-4-diethylamino ethyl piperazine
1-(4'-Benzyloxy benzyl)-2-phenyl piperazine prepared according to Example 10, is alkylated by means of diethylamino ethylchloride by following the procedure described in Example 2 (c). The resulting reaction product is obtained in the form of a light yellow oil boiling at 235° C./0.01 mm. Hg.
EXAMPLE 18
1-(3',4',5'-Trimethoxy benzyl)-2-phenyl-4-diethylamino ethyl piperazine
1-(3',4',5'-Trimethoxy benzyl)-2-phenyl piperazine prepared according to Example 11, is alkylated by means of diethylamino ethylchloride by following the procedure described in Example 2 (c). The resulting reaction product is obtained in the form of yellow oil boiling at 200° C./0.03 mm. Hg.
EXAMPLE 19
1-[3'-(4"-Methoxy phenyl) propyl(1)]-2-phenyl-4-diethylamino ethyl piperazine
1-[3'-(4"-Methoxy phenyl) propyl(1)]-2-phenyl piperazine prepared according to Example 12, is alkylated by means of diethylamino ethylchloride by following the procedure described in Example 2 (c). The resulting reaction product is obtained in the form of a yellow oil boiling at 130°-190° C./0.01 mm. Hg.
EXAMPLE 20
1-(4'-Ethoxy benzyl)-3-phenyl-4-diethylamino ethyl piperazine
1-Diethylamino ethyl-2-phenyl piperazine prepared according to Example 7 (a), is reacted with 4-ethoxy benzylchloride by following the procedure described in Example 7 (b) and using, in place of 4-chloro benzylchloride, the equimolecular amount of 4-ethoxy benzylchloride. The resulting reaction product is obtained in the form of a yellow oil boiling at 200° C./0.05 mm. Hg.
EXAMPLE 21
1-(4'-Chloro benzyl)-2-phenyl-4-(diethylamino ethyl) piperazine ##STR32##
A. 1-(4-Chloro benzyl)-2-phenyl-4-(β-hydroxy ethyl) piperazine ##STR33##
a. 30 g. of 1-(4'-chloro benzyl)-2-phenyl piperazine, prepared according to Example 1 A), 20 g. of ethylene chlorohydrin, 20 g. of triethylamine and 250 cc. of methyl ethyl ketone are boiled under reflux for 24 hours. After cooling, the triethylamine hydrochloride formed thereby is removed by filtration, the filtrate is evaporated in a vacuum, the residue is dissolved in benzene, the benzene solution is washed with water and dried over anhydrous potassium carbonate. The benzene is removed by distillation and the residue is distilled in a vacuum. A yellow, viscous oil of the boiling point 195° C./0.01 mm. Hg is obtained. The oil is twice recrystallized from isopropanol and then from n-heptane. Melting point 91-94° C.; yield 22 g.
b. A mixture of 28.6 g. of 1-(4'-chloro benzyl)-2-phenyl piperazine, 6.0 g. of ethylene oxide and 200 cc. of methanol is let standing for 4 days in a closed flank at room temperature. Then the methanol is distilled off and the residue is distilled at 193° C./0.01 mm. Hg. The base is twice recrystallized from n-heptane, whereby a product having a melting point of 91°-94° C. is obtained. Yield 19 g.
c. 50 g. of 1-(4'-chloro benzyl)-2-phenyl piperazine are dissolved in 100 cc. of dioxane. To this solution are added 31 g. of acetylglycolic acid chloride, dissolved in 50 cc. of dioxane. The mixture boiled for 2 hours under reflux. The dioxane is distilled off in a vacuum and the residue is dissolved in benzene; the benzene solution is washed with an aquous 10 % sodium hydroxide solution and is dried over anhydrous potassium carbonate. The solvent is distilled off and the residue is recrystallized three times from isopropanol. Melting point 136°-137° C.; yield 46 g.
44 g. of the piperazine derivative obtained as above are dissolved in 120 cc. of absolute dioxane and added slowly drop to drop to a suspension of 10 g. of LiAlH 4 in 700 cc. of absolute ether. The mixture is boiled under reflux for 2.5 hours. It is then decomposed by adding 10 cc. of 15 % sodium hydroxide solution, 10 cc. of water, 30 cc. of 15 % sodium hydroxide solution and 20 cc. of water. The precipitated inorganic material is separated by filtration and the solvent is distilled in a vacuum. The residue is recrystallized three timed from n-heptane. The obtained compound has a melting point of 91°-94° C. Yield 17 g.
B. 1-(4'-Chloro benzyl)-2-phenyl-4-(2-chloro ethyl)pierazine hydrochloride. ##STR34##
24 g. of 1-(4'-chloro benzyl)-2-phenyl-4-(β-hydroxy ethyl) piperazine are dissolved in 150 cc. of chloroform and added drop by drop to a solution of 15 g. of thionyl chloride in 150 cc. of chloroform. The mixture is boiled under reflux for 5 hours and the solvent is removed in a vacuum by heating the mixture in a water bath. Excess of absolute ethanolic hydrochloric acid is added and the remaining acid is distilled off. The crystalline residue obtained is recrystallized from absolute ethanol. Melting point 178°-195° C. (dec.); yield 30 g.
C. 1-(4'-Chloro benzyl)-2-phenyl-4-(diethylaminoethyl) piperazine.
20 g. of 1-(4'-chloro benzyl)-2-phenyl-4-(β-chloro ethyl) piperazine hydrochloride, 14 g. of diethylamine and 200 cc. of acetone are boiled under reflux for 12 hours. After cooling, the precipitated diethylamino hydrochloride is filtered off with suction and the solvent of the filtrate is evaporated in a vacuum. The residue is distilled in a vacuum. 15 g. of a light yellow oil having a boiling point of 190° C./0.06 mm. Hg are obtained. This product is identical with the product as obtained according to Example 1 B.
EXAMPLE 22
1-(4'-Chloro benzyl)-2-phenyl-4-[(4"-methyl)-piperazino ethyl-(1)] piperazine. ##STR35##
47 g. of 1-(4'-chloro benzyl)-2-phenyl-4-(β-chloro ethyl) piperazine hydrochloride, 16.5 g. of N-methyl piperazine, 75 cc. of triethylamine and 300 cc. of methyl ethyl ketone are boiled under reflux for 12 hours. After cooling the precipitated triethylamino hydrochloride is filtered off with suction and the solvent is distilled off in a vacuum. The residue is dissolved in benzene, the benzene solution is washed with water and dried over anhydrous potassium carbonate. The solvent is distilled off and the residue is disssolved in absolute ethanol. Absolute ethanolic hydrochloric acid is added to precipitate the hydrochloride salt. After cooling the precipitation is separated by filtration, washed with absolute ethanol and dried. Melting point 250°-269° C. (decomposition). To obtain the free base the hydrochloride is dissolved in water and the base is set free from its hydrochloride solution by the addition of ammonia and extracted with benzene. The benzene solution is dried over anhydrous potassium carbonate, the solvent is distilled off and the residue is distilled in a vacuum. Boiling point 220-223° C./0.01 mm. Hg. Yield 30 g.
EXAMPLE 23
1-(4'-Chloro benzyl)-2-phenyl-4-[(3"-keto)piperazino ethyl-(1")] piperazino.
25 g. of 1-(4"-chloro benzyl)-2-phenyl-4-(β-chloro ethyl) piperazine hydrochloride, 7.3 g. of mono keto piperazine, 200 cc. of methyl ethyl ketone and 200 cc. of triethylamine are boiled for 24 hours under reflux. The precipitated triethylamine hydrochloride is filtered off with suction. Then, the solvent is evaporated, the residue is dissolved in benzene and the benzene solution is washed with water and dried over anhydrous potassium carbonate. The solvent is distilled off and the residue is distilled at 230°-250° C./0.06 mm. Hg (minor decomposition). The distilled product is dissolved in ether, washed with 0.5N hydrochloric acid. The extract obtained with the diluted hydrochloric acid is treated with carbon aand after filtration, the base is set free from said solution by use of ammonia. The base is dissolved in benzene, dried over anhydrous potassium carbonate and after evaporation of the solvent, the residue is distilled at 220°-230° C. (air bath temperature)/0.005 mm. Hg. A very viscous, brownish oil is obtained.
The acid addition salts of the bases according to the present invention are prepared in a manner known per se. For instance, anhydrous ethanolic hydrochloric acid is added to the base whereby the hydrochloride precipitates and is isolated by filtration. Or the base is triturated with the equimolecular amount of the respective acid either as such or in aqueous solution or in solution in an organic solvent and, if required, evaporating the solvent.
Specific procedures to prepare the acid addition salts are the following:
To prepare the hydrochlorides, the bases are dissolved in absolute ethanol and an equimolecular amount of abslute ethanolic hydrochloric acid is added. After cooling, the precipitated hydrochloride is separated by filtration and recrystallised from absolute ethanol or isopropanol.
The succinates or fumarates, respectively, may be obtained using an equimolar amount succinic acid or fumaric acid, respectively, which is added and to the base dissolved in acetone. After boiling under reflux, e.g. for 2 hours, the mixture is cooled and the precipitated salts are separated. The so obtained salts are pure for analysis. In case that the fumarates or succinates, respectively, are not separated from the mixture in crystalline form, the solvent is evaporated and the remaining syrup is triturated to induced crystallization. Recrystallization may be effected by use of ethyl acetate.
To prepare the sulfates, the base is dissolved in absolute ethanol and an equimolecular amount of dilute sulfuric acid is added. The obtained sulfates may be recrystallized from ethanol.
The preparation of the phosphates may be effected by dissolution of the base in absolute ethanol, and addition of an equimolecuar amount of dilute phosphoric acid. The phosphate may be precipitated by use of acetic acid ethyl ester and may be recrystallized by use of isopropanol.
The following acid addition salts have been prepared and isolated:
__________________________________________________________________________Ex- Acid addi-ampleBase tion salt Melting point__________________________________________________________________________24 1-(4'-Chloro benzyl)-2-phenyl- Dihydro- 255-1270° C. with4-diethylamino ethyl piperazine chloride decomposition25 1-(3',4'-Dichloro benzyl)-2- Dihydro- 220-222° C.phenyl-4-diethylamino ethyl chloridepiperazine26 1-(3',4'-Dichloro benzyl)-2- o-Phos- 220-226° C.phenyl-4-diethylamino ethyl phatepiperazine27 1-(3',4'-Dichloro benzyl)-2- Sulfate 210-214° C.phenyl-4-diethylamino ethylpiperazine28 1-(4'-Chloro benzyl)-2-phenyl- Succinate 156-158° C.4-piperidino ethyl piperazine29 1-(4'-Chloro benzyl)-2-phenyl-4- Fumar- 190° C. sublimatespiperidino ethyl piperazine ate 250-251° C. with de- composition30 1-[(4'-Methoxy phenyl)ethyl]- Hydro- 190-201° C.2-phenyl-4-diethylamino ethyl chloridepiperazine31 1-[3"-Phenyl propyl(1)]-2- Hydrochloride 185-192° C.piperazine32 1-(4'-Chloro benzyl)-3-phenyl- Hydrochloride 241-255° C.4-diethylamino ethyl piperazine with decom- position33 1-(4'-Chloro benzyl)-2-phenyl- Succin- 95-101° C.4-diethylamino ethyl piperazine ate__________________________________________________________________________
EXAMPLE 34
4-Diethylaminoethyl-3-phenyl-1-o-hydroxy benzyl) piperazine ##STR36##
a. 4-Diethylaminoethyl-3-phenyl-1-(o-acetoxy benzoyl)piperazine is prepared by boiling under reflux 15 g. of 1-diethylaminoethyl-2-phenyl-piperazine dissolved in 100 ml. of methyl ethyl ketone with 11 g. of acetyl salicyclic acid chloride dissolved in 50 ml. methyl ethyl ketone, for 6 hours. The solvent is removed by distillation. The residue is dissolved in water. The aqueous solution is extracted with benzene. Ammonia is added to the aqueous layer until its reaction is alkaline and the thus precipitated oil is extracted with benzene. The benzene extract is dried by means of potassium carbonate and the benzene is distilled off. The residue is distilled in a vacuum. Boiling point: 190° C./0.01 mm. (bath temperature). Light yellow, viscous oil.
b. 4-Diethylaminoethyl-3-phenyl-1-(o-hydroxy benzoyl) piperazine is obtained by dissolving the reaction product prepared as described hereinabove under (a) in 100 ml. of dilute hydrochloric acid (2 : 100). The solution is heated to 50° C. for one hour an is then rendered alkaline by the addition of ammonia. The precipitated viscous product is extracted with benzene, the benzene solution is dried by means of potassium carbonate. The benzene is removed by distillation and the residue is distilled in a vacuum. Boiling point: 180° C./0.001 mm. (bath temperature). Light yellow, vitreous product.
c. 4-Diethylaminoethyl-3-phenyl-1-(o-hydroxy benzyl) piperazine is obtained by dissolving 40 g. of 4-diethylaminoethyl-3-phenyl-1-(o-hydroxy benzoyl) piperazine in 150 ml. of dioxane and slowly adding said solution to a suspension of 6 g. of lithium aluminum hydride in 800 ml. of absolute ether. The reaction mixture is boiled under reflux for two hours. The resulting complex compound is decomposed by a treatment with 5 ml. of 15% sodium hydroxide solution followed by 5 ml. of water, 15 ml. of 15% sodium hydroxide solution, and finally 10 ml. of water. The resulting precipitate is filtered off and the solvent is distilled off from the filtrate. The residue is distilled in a vacuum. Boiling point: 180° C./0.001 mm. (bath temperature). Yellow oil.
EXAMPLE 35
1-(p-Hydroxy benzyl)-2-phenyl-4-diethylaminoethyl piperazine ##STR37##
a. 1-(4-Benzyloxy benzyl)-2-phenyl-3-keto piperazine is obtained by boiling under reflux 48 g. of 4-benzyloxybenzyl chloride, 35 g. of 2-phenyl-3-keto piperazine, 500 ml. of acetone, and 50 ml. of triethylamine for 14 hours. Thereafter, the acetone is distilled off and the residue is treated with water. The precipitated crystals are filtered of and are recrystallized from dioxane and thereafter from a mixture of dimethylformamide and water (1 : 1). Melting point: 207°-211° C. White crystals.
b. 1-(4-Benzyloxybenzyl)-2-phenyl piperazine is obtained by suspending 39 g. of the compound prepared according to (a) hereinabove in 150 ml. of dioxane. The suspension is added to a suspension of 10 g. of lithium aluminum hydride (LiAlH 4 ) in 900 ml. of ether. The resulting mixture is boiled under reflux for two hours. The complex compound formed thereby is decomposed by treatment with 10 ml. of 15% sodium hydroxide solution, followed by a treatment with 10 ml. of water, 30 ml. of 15% sodium hydroxide solution, and finally with 20 ml. of water. The decomposed mixture is filtered. The filter residue is discarded. The filtrate is evaporated to dryness and the evaporation residue is recrystallized from dioxane. melding point: 140°-141° C., white crystals.
c. 1-(4-Benzyloxybenzyl)-2-phenyl-4-diethylaminoethyl piperazine is obtained by boiling under reflux 25 g. of the compound prepared according to (b) hereinabove with 10.5 g. of diethylaminoethyl chloride, 30 ml. of triethylamine. and 200 ml. of acetone for six hours. The precipitated triethylamine hydrochloride is filtered off. The acetone is distilled of and the residue is dissoved in benzene. The benzene solution is extracted with dilute hydrochloric acid (1 : 10). The acid solution is made alkaline by the addition of ammonia and the precipitated oil is extracted with benzene. After distilling off the benzene, the residue is distilled in a vacuum. Boiling point: 235° C./0.01 mm. Yellow oil.
d. 1-(p-Hydroxybenzyl)-2-phenyl-4-diethylamino ethyl piperazine is obtained by dissolving 15 g. of the compound prepared as described under (c) in 500 ml. of toluene. 5 g. of palladium deposited on asbestos are added thereto. Hydrogen is passed into the solution under a positive pressure of 15 mm. mercury. Progress of the hydrogenating debenzylation is ascertained by thin-layer chromatography. Introduction of hydrogen is discontinued after 20 hours. The catalyst is filtered off. The toluene is distilled off and the residue is triturated with petroleum ether. The precipitated crystals are filtered off by suction. The filter residue is dissolved in warm acetone and is precipitated by the addition of petroleum ether. After filtering off by suction the precipitate and drying it, white crystals of the melting point 108°-112° C. are obtained.
EXAMPLE 36
1-(3,4-Dihydroxy benzyl)-2-phenyl-4-diethylaminoethyl piperazine ##STR38## The compound is prepared in an analogous manner as described in Example 35 by using as starting material 1-(3,4-dibenzyloxybenzyl)-2-phenyl-3-keto piperazine. Light yellow, very viscous oil. Boiling point: 245° C./0.001 mm.
EXAMPLE 37
4-Diethylaminoethyl-3-phenyl-1-(3,4-dibenzyloxy benzyl) piperazine hydrochloride. ##STR39## 30 g. of 3,4-dibenzyloxy benzylchloride, 23 g. of 1-diethylamino ethyl-2-phenyl piperazine, 20 ml. of triethylamine, and 200 ml. of methylethylketone are boiled under reflux for 12 hours. The precipitated triethylamine hydrochloride is filtered off by suction. The solvent is distilled off and the residue is dissolved in benzene. The benzene solution is extracted with dilute hydrochloric acid (1 : 8). The hydrochloric acid extract is rendered alkaline by the addition of ammonia and is extracted with benzene. The benzene is removed from the benzene extract by distillation. Water-free alcoholic hydrochloric acid is added to the residue, and the hydrochloride of the resulting base is precipitated by the addition of a mixture of petroleum ether and acetone (1 : 1). The hydrochloride is redissolved in alcohol and is again precipitated by the addition of petroleum ether and acetone. Melting point of the hydrochloride: It starts to sublimate at 203° C. and melts at 235°-239° C. with decomposition. White crystals.
EXAMPLE 38
1-(p-Chloro benzyl)-2-phenyl-4-morpholino ethyl-3-keto piperazine ##STR40##
45 g. of 1-(4-chloro benzyl)-2-phenyl-3-keto piperazine,
56 g. of morpholino ethylchloride,
50 g. of potassium carbonate, and
500 ml. of toluene
are boiled under reflux for 20 hours. Water is added to the reaction mixture and undissolved matter is filtered off therefrom. The clear toluene solution is extracted with 250 ml. of N hydrochloric acid. The extract is rendered strongly alkaline by the addition of ammonia and the precipitated base is extracted with benzene. After drying the benzene extract, the solvent is distilled off and the residue is recrystallized from isopropanol, yielding a first crystal fraction. The mother lye is concentrated by evaporation to a small volume and is cooled. Precipitated crystals are filtered off by suction. They represent the second crystal fraction. Since both fractions still contain unreacted starting material, they are triturated with 60 ml. of N acetic and undissolved matter is filtered off. The clear acetic acid solution is rendered strongly alkaline by the addition of ammonia and is extracted with benzene. The benzene is distilled off after drying the extract. The remaining residue is recrystallized from isopropanol. Melting point: 117°-119° C. Yield: 10 g.
EXAMPLE 39
1-(2-Chloro benzyl)-2-phenyl-4-morpholino ethyl-3-keto piperazine ##STR41## 45 g. of 1-(2-chloro benzyl)-2-phenyl-3-keto piperazine obtained as described in Example 46 (a),
56 g. of morpholino ethyl chloride,
50 g. of potassium carbonate, and
500 ml. of toluene
are boiled under reflux for 20 hours. The reaction mixture is poured into water. Undissolved matter is separated. The toluene solution is extracted with 250 ml. of N hydrochloric acid. The hydrochloric acid extract is rendered strongly alkaline by the addition of ammonia and the precipitated base is extracted with benzene. After drying, the solvent is distilled off from the extract. The residue is dissolved in 100 ml. of N acetic acid. The crystals formed after allowing the solution to stand for a short period of time, are separated. The acetic acid filtrate is rendered strongly alkaline by the addition of ammonia and the precipitated base is extracted with benzene. After drying the benzene extract and distilling off the solvent, the residue is recrystallized from ispropanol. Melting point: 104°-106° C. Yield: 8.5 g.
EXAMPLE 40
1-(p-Chloro benzyl)-2-phenyl-4-dimethylamino propyl piperazine ##STR42## 28.6 g. of 1-(p-chloro benzyl)-2-phenyl piperazine, 15.0 g. of dimethylaminopropylchloride,
50 ml. of triethylamine, and
100 ml. of methyl ethyl ketone
are boiled under reflux for 20 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The solvent is distilled off. The residue is dissolved in 100 cc. of N hydrochloric acid. The hydrochloric acid extract is twice washed with benzene and is then rendered alkaline by the addition of ammonia. The oily base is separated in a separating funnel and is dissolved in 100 ml. of isopropanol. Solid potassium hydroxide is added to the isopropanol solution in order to remove the water present therein. The isopropanol solution is then filtered through a layer of potassium carbonate. After distilling off the solvent, a yellow viscous oil is obtained. The oil is dissolved in 1.5 liters of petroleum ether. Small amounts of impurities are filtered off and the petroleum ether is distilled off. The crude base is dissolved in benzene and is extracted with 25% acetic acid. The base is set free from said extract by the addition of ammonia. The base is again dissolved in benzene and dried by means of potassium carbonate. The solvent is distilled off and the residue is distilled in a vacuum. Boiling point: 180°-184° C./0.08 mm. Yield: 14 g.
EXAMPLE 41
1-(3,4-Dibenzyloxy benzyl)-2-phenyl-4-diethylamino ethyl piperazine fumarate ##STR43##
a. 23.2 g. of 2-phenyl-3-keto piperazine,
50.0 g. of 3,4-dibenzyloxy benzylchloride,
30 ml. of triethylamine, and
300 ml. of methyl ethyl ketone
are boiled under reflux for 3 hours. After cooling, precipitated triethylamine hydrochloride is filtered off by suction. The solvent is then distilled off. The residue is dissolved in 50 ml. of acetone. The acetone solution is poured into 500 ml. of water. The precipitated crystallized product is filtered off and is twice recrystallized from isopropanol. Melting point: 108°-110° C. Yield 46 g.
b. 44 g. of the compound as described hereinabove under (a) are suspended into
250 ml. of dioxane.
The suspension is added drop by drop to a suspension of
7 g. of lithium aluminum hydride in
500 ml. of ether.
Thereafter the reaction mixture is boiled under reflux for one hour. After decomposing the lithium aluminum hydride complex compound, the ethereal solution is separated, the ether is distilled off, and the residue is recrystallized from isopropanol. Melting point: 54°-55° C. Yield: 25 g.
c. 25 g. of the compound obtained as described hereinabove under (b),
9 g. of diethylamino ethylchloride,
15 ml. of triethylamine, and
150 ml. of methyl ethyl ketone
are boiled under reflux for 10 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The filtrate is evaporated by distillation to dryness and the residue is dissolved in benzene. The benzene solution is washed with 20% sodium hydroxide solution. The washed benzene layer is separated and extracted with 150 ml. of N hydrochloric acid. The base is set free from said hydrochloric acid extract by the addition of ammonia. It is extracted therefrom with benzene. The benzene solution is dried and the solvent is distilled off. The residue is dissolved in 100 ml. of acetone. 5 g. of fumaric acid are added to said solution which is heated to boiling on the water bath. Small amounts of insoluble matter are filtered off and the solution is cooled. The precipitated fumarate is recrystallized from 96% ethanol. Melting point: 152°-154° C. Yield: 22 g.
EXAMPLE 42
1-(o-benzyloxy-benzyl)- 2-phenyl-4-diethylamino ethyl piperazine ##STR44##
a. 38 g. of 2-phenyl-3-keto piperazine,
52 g. of o-benzyloxy benzylchloride,
50 ml. of triethylamine, and
400 ml. of methyl ethyl ketone
are boiled under reflux for four hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The methyl ethyl ketone is distilled off. The residue is dissolved in isopropanol and water is added thereto, while heating, until crystallization sets in. Melting point: 159°-160° C. Yield: 50 g.
b. 39 g. of the compound prepared as described hereinabove under (a) are dissolved in
100 ml. of anhydrous dioxane.
The solution is added drop by drop to a suspension of
10 g. of lithium aluminum hydride in 900 ml. of absolute ether. Thereafter the mixture is boiled under reflux for one and a half hours. The resulting lithium aluminum hydride complex compound is decomposed by a treatment with 10 ml. of 15% sodium hydroxide solution followed by a treatment with 10 ml. of water, 30 ml. of 15% sodium hydroxide solution, and finally 20 ml. of water. The solution is filtered. The solvent is distilled off. The residue is dissolved in benzene and the benzene solution is extracted with 300 ml. of N/2 hydrochloric acid. The hydrochloric acid extract is rendered strongly alkaline by the addition of ammonia. The precipitated base is extracted with benzene. The benzene solution is dried and the benzene is distilled off. The remaining base is distilled in a vacuum. Boiling point: 205° C./0.03 mm. The base is then recrystallized twice from n-heptane. Melting point: 82°-85° C. Yield: 35 g.
c. 30 g. of the compound prepared as described hereinabove under (b),
12.5 g. of diethylamino ethylchloride,
30 ml. of triethylamine, and
150 ml. of methyl ethyl ketone
are boiled under reflux for 12 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The solvent is distilled off from the filtrate. The residue is dissolved in benzene. The benzene solution is extracted with 300 ml. of N hydrochloric acid. The base is precipitated from the hydrochloric acid extract by the addition of ammonia. The precipitated base is then extracted with benzene. The benzene solution is dried by means of potassium carbonate and the solvent is distilled off. The residue is distilled in a vacuum. Boiling point: 230°-235° C./0.03 mm. Yield: 25 g.
EXAMPLE 43
1-(p-Methoxy benzyl)-2-phenyl-4-diethylamino propyl piperazine ##STR45##
28 g. of 1-(p-methoxy benzyl)-2-phenyl piperazine obtained as described hereinabove in Example 3 (b),
20 g. of diethylamino propylchloride,
50 ml. of triethylamine, and
200 ml. of methyl ethyl ketone
are boiled under reflux for 12 hours. Precipitated triethylamine hydrochloride is filtered off. The solvent is removed by distillation. The residue is dissolved in benzene. The benzene solution is extracted with an acetic acid-water mixture 1 : 7). The acetic acid solution is separated from the benzene solution and is rendered alkaline by the addition of ammonia. The precipitated oily base is extracted in benzene, dried by means of potassium carbonate, and the benzene is distilled off. The remaining base is distilled in a vacuum. Boiling point: 200° C./0.01 mm.
The crude base is dissolved in 100 ml. of absolute ethanol and the solution is acidified by the addition of absolute alcoholic hydrochloric acid to a pH of 1.0. The precipitated hydrochloride is filtered off by suction and dried. The salt starts to sublimate at 200° C. and melts at 228°-231° C. with decomposition. The hydrochloride is dissolved in water. The base is set free by the addition of ammonia and is extracted with benzene. The benzene is distilled off from the benzene solution. The remaining base is again distilled in a vacuum. Boiling point: 210° C./0.02 mm. Colorless oil. Yield: 21 g.
EXAMPLE 44
1-(3-Chloro benzyl)-2-phenyl-4-diethylamino ethyl piperazine ##STR46##
a. 17.5 g. of 1-(3-chloro benzyl)-2-phenyl-3-keto piperazine obtained as described in Example 44 (a) of Application Ser. No. 333,497
are suspended in 50 ml. of absolute dioxane. The suspension is added drop by drop, while stirring, to a suspension of
4.5 g. of lithium aluminum hydride in
400 ml. of absolute ether.
Thereafter, the reaction mixture is boiled under reflux for one and a half hours. The resulting complex compound is decomposed by a treatment first with
4.5 ml. of 15% sodium hydroxide followed by a treatment with 4.5 ml. of water,
14.5 ml. of 15% sodium hydroxide solution, and finally 9.0 ml. of water.
The hydroxide precipitate is filtered off and the solvent is distilled off from the filtrate. The residue is dissolved in 20 ml. of N acetic acid. After allowing the solution to stand for 24 hours, the solid precipitate is filtered off. The filtrate is rendered alkaline by the addition of ammonia and the precipitated base is extracted with benzene. After drying the benzene solution, the solvent is distilled off. The residue is dissolved in 30 ml. of absolute ethanol and is adjusted to a pH of 1.0 by the addition of absolute alcoholic hydrochloric acid. The precipitated hydrochloride is filtered off by suction and dried. Melting point: 239°-242° C. The hydrochloride is dissolved in water. The base is set free by the addition of ammonia and is extracted with benzene. After drying the benzene solution and distilling off the benzene, the oily residue is distilled in a vacuum. Boiling point: 145° C./0.05 mm. Colorless oil.
b. 10 g. of the base obtained as described hereinabove under (a),
150 ml. of acetone,
9.0 g. of diethylamino ethylchloride, and
10 ml. of triethylamine
are boiled under reflux for 14 hours. The reaction mixture is cooled and the precipitated triethylamine hydrochloride is filtered off by suction. The filtrate is evaporated to dryness. The residue is dissolved in benzene. The benzene solution is extracted with 100 ml. of N hydrochloric acid. The hydrochloric acid extract is rendered alkaline. The precipitated base is extracted with benzene. The benzene solution is then dried by means of potassium carbonate and the benzene is distilled off. The remaining residue is distilled in a vacuum. Boiling point: 170° C./0.07 mm. Yellowish, mobile oil. Yield: 12 g.
EXAMPLE 45
1-(2-Chloro benzyl)-2-phenyl-4-diethylamino ethyl piperazine ##STR47##
a. 51 g. of 1-(2-chloro benzyl)-2-phenyl-3-keto piperazine prepared as described in Example 46 (a) of Application Serial No. 333,497 are suspended in
100 ml. of dioxane.
The suspension is added to a suspension of
11 g. of lithium aluminum hydride in
700 ml. of absolute ether and
50 ml. of dioxane,
while stirring. Thereafter, the reaction mixture is boiled under reflux for one and a half hours. The resulting complex compound is decomposed first by a treatment with
11 ml. of 15% sodium hydroxide solution followed by a treatment with
11 ml. of water,
33 ml. of 15% sodium hydroxide solution, and finally with
22 ml. of water.
After filtering off by suction the hydroxide precipitate, the solvent is distilled off from the filtrate. The residue is dissolved in 100 ml. of absolute ethanol and 35 ml. of alcoholic hydrochloric acid (about 8 N) are added thereto. The precipitated hydrochloride is filtered off by suction, washed, and dried. Melting point: 276°-277° C. The hydrochloride is dissolved in water. The base is set free therefrom by the addition of ammonia and is extracted with benzene. The benzene solution is dried and the solvent is distilled off. The remaining base is distilled in a vacuum. Boiling point: 136° C./0.08 mm. Yield: 38 g.
b. 10 g. of the base obtained as described hereinabove under (a),
150 ml. of acetone,
9 g. of diethylamino ethylchloride, and
10 ml. of triethylamine
are boiled under reflux for 14 hours. The reaction mixture is cooled and the precipitated triethylamine hydrochloride is filtered off by suction. The filtrate is then evaporated to dryness. The residue is dissolved in water and is extracted with benzene. The benzene solution is separated from the aqueous phase and is extracted with 50 ml. of N hydrochloric acid. The hydrochloric acid extract is rendered alkaline by the addition of ammonia and the base set free thereby is extracted with benzene. The benzene solution is dried by means of potassium carbonate and the solvent is distilled off. The residue is distilled in a vacuum. Boiling point: 160° C./0.05 mm. Yield: 11.5 g.
EXAMPLE 46
1-(3-Trifluoromethyl benzyl)-2-phenyl-4-diethylamino ethyl piperazine ##STR48##
a. 60 g. of 1-(3-trifluoromethyl benzyl)-2-phenyl-3-keto piperazine prepared as described in Example 51 (a) of Application Serial No. 333,497 are dissolved in
120 ml. of dioxane.
The solution is added drop by drop to a suspension of
14 g. of lithium aluminum hydride in
700 ml. of absolute ether and
50 ml. of dioxane,
while stirring. Thereafter, the reaction mixture is boiled under reflux for two hours. The resulting complex compound is decomposed first by a treatment with
14 ml. of 15% sodium hydroxide solution followed by a treatment with
14 ml. of water,
42 ml. of 15% sodium hydroxide solution, and finally
28 ml. of water.
The hydroxide precipitate is filtered off and the solvent is distilled off from the filtrate. The residue is dissolved in 200 ml. of absolute ethanol and 35 ml. of an absolute alcoholic solution of hydrochloric acid (8 N) added thereto. The precipitated hydrochloride is filtered off by suction. It is washed with a mixture of acetic acid ethyl ester and alcohol (1 : 1) and is dried. The resulting hydrochloride is dissolved in a small amount of water. The base is set free from said solution by the addition of ammonia and is extracted with benzene. The benzene solution is dried and the solvent is distilled off. The remaining base is distilled in a vacuum. Boiling point: 120° C./0.05 mm. Yield: 40 g.
b. 10 g. of the base obtained as described hereinabove under (a),
150 ml. of acetone,
9 g. of diethylamino ethylchloride, and
10 ml. of triethylamine
are boiled under reflux for 14 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The solvent is distilled off from the filtrate. The residue is dissolved in benzene. The benzene solution is washed once with water and is then extracted with 50 ml. of N hydrochloric acid. The hydrochloric acid extract is rendered alkaline by the addition of ammonia. The base set free thereby which forms the upper layer is extracted with benzene. The benzene solution is dried and the solvent is distilled off. The remaining base is distilled in a vacuum. Boiling point: 147° C./0.05 mm. Yellowish, mobile oil. Yield: 12.5 g.
EXAMPLE 47
1-(p-Chloro benzyl)-2-phenyl-4-piperazino ethyl piperazine ##STR49##
5 g. of 1-(p-chloro benzyl)-2-phenyl-4-[(3-keto)piperazino ethyl] piperazine obtained as described hereinabove in Example 23 are dissolved in
100 ml. of absolute dioxane.
The solution is added drop by drop to a suspension of 5 g. of lithium aluminum hydride in 500 ml. of absolute ether. After addition is completed, the reaction mixture is boiled under reflux for two hours. The resulting complex compound is then decomposed first by the addition of
5 ml. of 15% sodium hydroxide solution followed by the addition of
5 ml. of water,
5 ml. of 15% sodium hydroxide solution, and finally
10 ml. of water.
The inorganic hydroxides are filtered off from the reaction mixture and the solvent is distilled off. The residue is dissolved in benzene. The benzene solution is extracted with dilute acetic acid (1 : 10). Ammonia is added to the acetic acid solution. The precipitated base is extracted with benzene. The benzene solution is dried and the benzene is distilled off. The remaining base is distilled in a vacuum. Boiling point: 190° C./0.05 mm. Very viscous yellow oil. Yield: 3 g.
EXAMPLE 48
1-(p-Methoxy benzyl)-2-phenyl-4-piperidino ethyl piperazine ##STR50##
13 g. of 1-(p-methoxy benzyl)-2-phenyl piperazine obtained as described hereinabove in Example 4 (b),
10 g. of piperidino ethylchloride,
40 cc. of triethylamine, and
100 cc. of methyl ethyl ketone
are boiled under reflux for 18 hours. Without separating the precipitated triethylamine hydrochloride the solvent is distilled off. The residue is dissolved in benzene and water. The aqueous phase is separated and the benzene solution is extracted with dilute acetic acid (1 : 6). The acetic acid solution is then precipitated by the addition of ammonia. The precipitated base is extracted with benzene, dried by means of potassium carbonate, and the benzene is distilled off. The base is distilled in a vacuum. Boiling point: 210° C./0.001 mm. Light yellow, viscous oil. Yield: 15 g.
EXAMPLE 49
4-Diethylamino ethyl-3-phenyl-(3,4,5-trimethoxy benzyl) piperazine ##STR51##
20 g. of 1-diethylamino ethyl-2-phenyl piperazine prepared as described hereinabove in Example 8 (b),
17 g. of 3,4,5-trimethoxy benzylchloride,
250 ml. of acetone, and
20 ml. of triethylamine
are boiled under reflux for 8 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The acetone is distilled off in a vacuum. The residue is dissolved in benzene, and the benzene solution is extracted with 50 ml. of N hydrochloric acid. The hydrochloric acid extract is rendered alkaline by the addition of ammonia. The precipitated base is extracted with benzene. After drying by means of potassium carbonate, the solvent is distilled off. The remaining base is distilled in a vacuum. Boiling point: 210° C./0.05 mm. Yellowish, viscous oil. Yield: 19 g.
EXAMPLE 50
4-Diethylamino ethyl-3-phenyl-1-(p-chloro phenyl ethyl) piperazine ##STR52##
20 g. of 1-diethylamino ethyl-2-phenyl piperazine obtained as described hereinabove in Example 8 (b),
17 g. of p-chloro phenyl ethylchloride,
20 ml. of triethylamine, and
100 ml. of dimethylformamide
are heated on the water bath for 12 hours. The dimethylformamide is then distilled off in a vacuum. The residue is dissolved in acetone. The precipitated triethylamine hydrochloride is filtered off by suction and the acetone is distilled off from the filtrate. The resulting base is dissolved in benzene and extracted with 50 ml. of N hydrochloric acid. The hydrochloric acid extract is precipitated by the addition of ammonia. The precipitated base is extracted with benzene. The benzene solution is dried by means of potassium carbonate and the benzene is distilled off therefrom. The remaining base is distilled in a vacuum. Boiling point: 190° C./0.02 mm. Yield: 13 g.
EXAMPLE 51
4-Diethylamino ethyl-3-phenyl-1-(o-benzyloxy benzyl) piperazine ##STR53##
27 g. of 1-diethylamino ethyl-2-phenyl piperazine prepared as described hereinabove in Example 8 (b),
27 g. of 2-benzyloxy benzyl chloride,
25 ml. of triethylamine, and
250 ml. of acetone
are boiled under reflux for 4 hours. The precipitated triethylamine hydrochloride is filtered off by suction. The acetone is removed by distillation. The residue is dissolved in benzene and water. The benzene solution is separated from the aqueous phase and is extracted with 100 ml. of 0.5 N hydrochloric acid. The hydrochloric acid extract is rendered alkaline by the addition of ammonia and the precipitated base is extracted with benzene. After drying the benzene extract, the solvent is distilled off. Boiling point: 232° C./0.03 mm. Yellowish oil. Yield: 26 g.
EXAMPLE 52
4-Diethylamino ethyl-3-phenyl-1-(p-benzyloxy benzyl) piperazine ##STR54##
30 g. of 1-diethylamino ethyl-2-phenyl piperazine obtained as described hereinabove in Example 8 (b),
100 ml. of methyl ethyl ketone,
50 ml. of triethylamine, and
24 g. of p-benzyloxy benzylchloride
are boiled under reflux for 12 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The methyl ethyl ketone is distilled off from the filtrate. The residue is dissolved in benzene and water. The benzene solution is separated from the aqueous phase and is extracted with 250 ml. of 0.1 N hydrochloric acid. The hydrochloric acid extract is rendered alkaline by the addition of ammonia. The precipitated base is extracted with benzene. The benzene solution is dried and the solvent is distilled off. Boiling point of the remaining base: 245° C./0.005 mm. Yellow, very viscous oil. The base is dissolved in a small amount of ethanol and its hydrochloride is precipitated from the solution by the addition of absolute alcoholic hydrochloric acid. The hydrochloride is filtered off by suction and is dried. The hydrochloride is dissolved in water. The base is set free by the addition of ammonia, extracted with benzene, dried, and the solvent is distilled off. The residue is recrystallized from petroleum ether. Melting point: 58° C. Yield: 33 g.
EXAMPLE 53
4-Diethylamino ethyl-3-phenyl-1-(p-hydroxy benzyl) piperazine ##STR55## 25 g. of 1-diethylamino ethyl-3-phenyl-4-(p-benzyloxy benzyl) piperazine obtained as described hereinabove in Example 52 are dissolved in 500 ml. of toluene. 4 g. of palladium asbestos are added thereto and hydrogen is introduced into the solution at room temperature under a positive pressure of 50 mm. Hg. A white, crystalline compound starts to precipitate on the catalyst after 15 hours. Introduction of hydrogen is discontinued. The catalyst is filtered off by suction and is washed with 500 ml. of 60° C. toluene. The toluene is distilled off and the remaining residue is recrystallized first from n-heptane and subsequently from isopropanol. Melting point: 144° C. Yield: 11 g.
EXAMPLE 54
4-Diethylamino ethyl-3-phenyl-1-benzyl piperazine ##STR56##
15 g. of 1-diethylamino ethyl-2-phenyl piperazine obtained as described hereinabove in Example 8 (b),
8 g. of benzylchloride,
150 ml. of methyl ethyl ketone, and
20 ml. of triethylamine
are boiled under reflux for 8 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The acetone is distilled off and the residue is dissolved in benzene. The benzene solution is extracted with 100 ml. of N-hydrochloric acid. The hydrochloric acid extract is rendered alkaline by the addition of ammonia. The precipitated base is extracted with benzene. The benzene solution is dried and the solvent is distilled off therefrom. The residue is distilled in a vacuum. Boiling point: 160° C./0.01 mm. Yellowish oil. Yield: 10 g.
EXAMPLE 55
4-Diethylamino ethyl-3-phenyl-1-(3,4-dibenzyloxy benzyl) piperazine hydrochloride ##STR57##
23 g. of 1-diethylamino ethyl-2-phenyl piperazine obtained as described hereinabove in Example 8 (b),
30 g. of 3,4-dibenzyloxy benzylchloride,
20 ml. of triethylamine, and
200 ml. of methyl ethyl ketone
are boiled for 12 hours under reflux. The precipitated triethylamine hydrochloride is filtered off by suction. The solvent is distilled off. The residue is dissolved in benzene. The benzene solution is extracted with 100 ml. of N hydrochloric acid. The hydrochloric acid extract is precipitated by the addition of ammonia. The precipitated base is dissolved in benzene, the benzene solution is dried and the solvent is distilled off. Absolute alcoholic hydrochloric acid is added to the residue in an amount to yield a pH of 1.0 and a mixture of petroleum ether and acetone (1:1) is slowly added thereto. The hydrochloride precipitates and is filtered off by suction. It is dissolved in alcohol and is again precipitated by careful addition of a mixture of petroleum ether and acetone (1:1).
The compound obtained after filtering and drying starts to sublimate at 203° C. and has a melting point of 235°-239° C. with decomposition. Yield: 39 g.
EXAMPLE 56
4-Diethylamino ethyl-3-phenyl-1-(p-methoxy benzyl) piperazine ##STR58##
64 g. of 1-diethylamino ethyl-2-phenyl piperazine obtained as described hereinabove in Example 8 (b),
39 g. of p-methoxy benzylchloride,
75 g. of triethylamine, and
500 ml. of acetone
are boiled under reflux for 7 hours. After cooling, the precipitated triethylamine hydrochloride is filtered off by suction. The filtrate is evaporated to dryness. The residue is dissolved in benzene and is extracted with 200 ml. of N hydrochloric acid. Ammonia is added to the hydrochloric acid extract and the precipitated base is extracted with benzene. The benzene solution is dried by means of potassium carbonate and the solvent is distilled off. The residue is distilled in a vacuum. Boiling point: 180°-182° C./0.005 mm. Yellowish oil. Yield: 24 g.
The new 1,4-substituted phenyl piperazine compounds to the present invention and their pharmaceutically acceptable acid addition salts can be administered orally, parenterally, or rectally. Compositions containing said compounds as used in therapy, comprise, for instance, tablets, pills, dragees, lozenges, and the like shaped preparations to be administered orally. Said compounds may also be administered in powder form, preferably enclosed in gelatin or the like capsules. Oral administration in liquid form, such as in the form of solutions, emulsions, suspensions, sirups, and the like is also possible. Such solid or liquid preparations are produced in a manner known to the art of compounding and processing pharmaceutical compositions whereby the conventional diluting, binding, and/or expanding agents, lubricants, and/or other excipients, such as lactose, cane sugar, dextrins, starch, talc, kaolin, magnesium hydroxide, magnesium carbonate, pectin, gelatin, agar, bentonite, stearic acid, magnesium stearate, and others may be employed.
The following examples serve to illustrate the preparation of pharmaceutical compositions as they are used in therapy without, however, limiting the same thereto.
EXAMPLE 57
Tablets:
20 g. of the dihydrochloride of 1-(4'-chloro benzyl)-2-phenyl-4-diethylamino ethyl piperazine, 128 g. of lactose, and 2 g. of magnesium stearate are intimately mixed with each other and are compressed without preceding granulation to tablets weighing 150 mg. Each tablet contains 20 mg. of the anticoagulant agent according to the present invention.
EXAMPLE 58
The mixture of ingredients as given in Example 57 is compressed to biconvex dragee cores of 150 mg. each. These cores are repeatedly sugar-coated by rotating in a coating pan with sugar sirup. Each dragee contains 20 mg.
EXAMPLE 59
Capsules:
500 g. of 1-(3',4'-dichloro benzyl)-2-phenyl-4-diethylamino ethyl piperazine dihydrochloride are intimately mixed with 200 g. of starch and the mixture is sieved. Portions of 700 mg. each of said mixture are filled in gelatin capsules. Each capsule contains 500 mg. of the anticoagulant agent.
EXAMPLE 60
Suppositories:
400 g. of the molten suppository base Adeps solidus and 10 g. of the succinate of 1-(4'-chloro benzyl)-2-phenyl-4-piperidino ethyl piperazine are thoroughly triturated while maintaining in the molten state. The molten mixture is cast into suppository molds, each of which contains 2.05 g. of the mixture. The molds are then cooled to cause solidification. Each suppository contains 50 mg. of the anticoagulant agent.
EXAMPLE 61
25 mg. of 1-(4'-chloro benzyl)-2-phenyl-4-diethylamino ethyl piperazine dihydrochloride are dissolved in 2.2 cc. of bidistilled water. This solution is filled in ampoules which are sterilized in an autoclave at 120° C.
Ampoules containing 5 mg. to 250 mg. of base may be prepared as follows: The base is dissolved in water by the addition of a stoichiometrically equivalent amount of the desired acid. As an acid, there may be used e.g. hydrochloric acid, phosphoric acid, nitric acid, sulfuric acid, succinic acid, fumaric acid, lactic acid, and the like.
The effect which 1,4-disubstituted phenyl piperazine compounds according to the present invention have on blood coagulation, was determined according to standard test methods in vitro with human blood. The results of such tests are given in the following Table. The test mixture was prepared by adding one part of the aqueous solution of the compound to be tested to 9 parts of plasma. The compound to be tested was used in the form of its hydrochloride. Thus 0.1 millimole (mM) as given in the Table indicates 9 ml. of plasma plus 1 ml. of a millimolar (mM) aqueous solution of the compound to be tested.
The effect of the compounds according to the present invention was determined by measuring the recalcification time as well as the stypven time.
The determination of the recalcification time is based on the fact that free calcium + + ions are required to cause coagulation. Because the calcium ions are bound in the blood which has been rendered non-coagulable by the addition of citrate or oxalate, excess calcium chloride solution is added in this test and the period of time calculated from the additon of the calcium chloride to the onset of coagulation is measured. This period of time is the recalcification time.
For determining the stypven time, there is added, in addition to the calcium ions, the viper poison stypven to the citrate or oxalate blood. The stypven test is an especially sensitive test for detecting lipides set free from the thrombocytes.
In order to determine the effect of the compounds according to the present invention upon thrombocytes which are principal features with respect to coagulation of blood, the recalcification time and the stypven time were determined in blood rich in thrombocytes as well as in blood poor in thrombocytes.
It is assumed that the formation of blood clots is initiated by thrombocyte aggregation. Therefore, the compounds according to this invention were also tested for their thrombocyte aggregation, inhibiting effect by the method described by Klaus Breddin in "Schweizerische Medizinische Wochenschrift" vol. 20, p. 655 (1965).
The following Table shows those concentrations of the tested compounds, determined by means of their recalcification time and their stypven time, which indicate a pronounced blood coagulation promoting effect as well as a pronounced blood coagulation inhibiting effect. These concentrations are given in millimoles of the respective compound. The concentrations at which inhibition of the thrombocyte aggregation sets in, are also given for some of the compounds. That one and the same compound can have a blood coagulation promoting as well as a blood coagulation inhibiting effect, is due to the fact that it acts upon various coagulation factors at the same time. Thus a compound is able to set free from the thrombocytes coagulation activating material at a low concentration while at a higher concentration certain coagulation factors have an inhibiting effect.
o in said Table indicates that no effect has been found within the tested concentration range.
The recalcification time was determined according to the method of E. DEUTSCH ET AL. in "Thrombosis et Diathesis Haemorrhagica" vol. XXVI, page 145(1971) and the stypven time according to the method of McKENZIE ET AL. in "Amer. Journ. Clin. Path." vol. 55, pages 551-554.
It has also been found that a number of the compounds according to the present invention possess fibrinolytic activity, i.e. they are capable of dissolving thrombi which have been formed.
TABLE__________________________________________________________________________ Coagulation promoting Coagulation inhibiting Inhibition of effect effect thrombocytes Plasma rich Plasma poor Plasma rich Plasma poor aggregationExam- in in in in according tople Molecular thrombocytes thrombocytes BreddinNo. Compound weight mM mM mM mM mM__________________________________________________________________________ 1-(4-Chloro benzyl)-2- phenyl-4-diethylamino- ethyl-3-keto-piperazine 399.9 1 1 55 5 0.11 4-Diethylaminoethyl-2- phenyl-1-(4-chloro benzyl) piperazine 386.0 1 1 5 5 12 1-(3,4-Dichloro benzyl)-2- phenyl-4-diethylaminoethyl- piperazine 420.4 0.1 - 1 1 2.5 2.5 0.13 1-(p-Methoxyphenyl-ethyl)- 2-phenyl-4-Methylamino ethyl piperazine 395.5 1 1 10 5 0.1-0.54 1-(3-Phenylpropyl)-2- phenyl-4-diethylamino- ethyl piperazine 379.5 0.1 - 1 1 5 2.5 0.1-0.55 1-(4-Chloro benzyl)-2- phenyl-4-(2-piperidino ethyl) piperazine 397.9 1 1 5 2.5-5 0.15 1-(p-chloro benzyl)-2- phenyl-4-[(4-methyl)-pip- erazine ethyl-(1)]piper- azine 413.01 0.1 0.1 2.5 2.5 0.15 1-(p-Chloro benzyl)-2-phenyl- 4-pyrrolidino ethyl pipera- zine 383.97 0.1 1 5 2.5 0.56 1-(4-Chloro benzyl)-2-phenyl- 4-(1,3-bis-(morpholino propyl) piperazine 499.08 1 1 5 2.5 0.1-17 1-(p-Chloro benzyl)-3-phenyl- 4-diethylamino ethyl piper- azine 386.1 0.1 1 5 2.5 0.01-0.18 4-Diethylaminoethyl-3-phenyl- 1-(p-ethoxy benzyl)piperazine 395.6 0.1-1 1 5 1-2.5 0.01-0.1 4-Diethylaminoethyl-3-phenyl- 2-keto-1-(p-chloro benzyl) piperazine 399.95 1 1 5 2.5-5 0.114 4-Dimethylaminoethyl-2-phenyl- 1-(3,4-dichloro benzyl)-pip- erazine 392,38 0.1 1 2.5 2.5 0.1-0.515 4-β-Morpholinoethyl-2-phenyl- (3,4-dichloro benzyl)pipera- zine 434.42 1 1 -- -- 0.116 4-Diethylaminopropyl-2-phen- yl-1-(3,4-dichloro benzyl) piperazine 434,462 0.1 1 2.5 2.5 0.0117 1-(4-Benzyloxy benzyl)-2- phenyl-4-diethylaminoethyl piperazine 457,66 0.1 0.1 2.5 2.518 4-Diethylaminoethyl-2-phen- yl-1-(3,4,5-trimethoxy ben- zyl) piperazine 4.41.596. 1 -- -- 5 0.119 1-[(p-Methoxy phenyl propyl)]- 2-phenyl-4-diethylaminoethyl piperazine 409,626 0.1 1 5 5 0.1-0.520 4-Diethylaminoethyl-3-phenyl- 1-(p-ethoxy benzyl)pipera- zine 395,6 0.1-1 1 5 1 - 2.5 0.1-0.522 1-(p-Chloro benzyl-2-phen- yl-4-[(4-methyl)piperazino ethyl-(1)]piperazine 413.01 0.1 0.1 5 2.523 1-(p-Chlorobenzyl)-2-phenyl- 4-[3-keto)-piperazinoethyl)- (1)] piperazine 466.99 0.1 0.5 o o5a 1-(p-Chloro benzyl)-2- phenyl-4-pyrrolidino ethyl piperazine 383,97 1 o 5 2.534 4-Diethylaminoethyl-3- phenyl-1-(o-hydroxy benzyl) piperazine 367.5 1 1 5 5 --36 4-Diethylaminoethyl-3-phen- yl-1-(3,4,5-trimethoxybenz- yl) piperazine 441.5 1 o o 2.5 --37 1-(p-Hydroxy benzyl)-2- phenyl-4-diethylaminoethyl piperazine 367.5 1 1 o o -- 1-(p-Ethoxy benzyl)-2-phen- yl-4-pyrrolidinoethyl-3- keto piperazine 407,53 1 1 o 547 1-(p-Chloro benzyl)-2-phen- yl-4-piperazino ethyl piperazine 399.0 0.1 0.1 2.5 548 1-(p-Methoxy benzyl)-2- phenyl-4-piperidinoethyl piperazine 393.55 1 o 5 2.549 4-Diethylaminoethyl-3-phen- yl-1-(3,4,5-trimethoxy)- benzyl piperazine 441,5 1 o o 2.550 4-Diethylaminoethyl-3- phenyl-1-(p-chloro phen- yl)ethyl piperazine 400.00 0.1 o 5 2.5 0.0551 4-Diethylamino ethyl-3- phenyl-1-(o-benzyloxy benzyl) piperazine 457.66 0.1 o 5 0.152 4-Diethylaminoethyl-3- phenyl-1-(p-benzyloxy benzyl) piperazine 457.66 0.1 1 2.5 2.5 153 4-Diethylaminoethyl-3- phenyl-1-(p-hydroxy benzyl)piperazine 367.5 0.1 o 10 5 --54 4-Diethylamino ethyl-3- phenyl-1-benzyl piper- azine 351.54 0.1 0.1 0 o55 4-Diethylaminoethyl-3- phenyl-1-(3,4-dibenzyl- oxy benzyl)piperazine . HC1 563.79 1 0.1 2.5 o 4-Diethylaminoethyl-3- phenyl-2-keto-1-(p-ben- zyloxy benzyl) pipera- zine 471.65 1 1 10 2.540 1-(p-Chloro benzyl)-2- phenyl-4-dimethylamino propyl piperazine 371,94 0.01 0.1 2.5 2.541 1-(3,4-Dibenzyloxy benzyl)- 2-phenyl-diethylaminoethyl piperazine fumarate 563.79 1 1 2.5 2.542 1-(o-Benzyloxy benzyl)-2- phenyl-4-diethylaminoethyl piperazine 457.66 0.1 1 5 2.543 1-(p-Methoxybenzyl)-2- phenyl-4-diethylamino propyl piperazine 395,57 0.1 o 5 5__________________________________________________________________________
The starting materials are either commercially available or can be synthesized from commercially available compounds by known methods.
For instance, α-chloro phenyl acetic acid ethyl ester used as the one reactant in Example 1 B (a), is prepared from commercially available α-chloro phenyl acetic acid chloride by esterifying with ethanol. Its boiling point is 123°-125° C./8-10 mm.
N 1 -(diethylamino ethyl) ethylene diamine, the other reactant of Example 1 B (a) is obtained according to the method of H. F. McKay "Canad. J. Chem." vol. 34, pp. 1567-1573 (1956).
1-(β-Chloro ethyl)-4-methyl piperazine used as reactant in Example 6, is prepared by reacting 1(β-hydroxy ethyl)-4-methyl piperazine and thionylchloride.
1,3-Dimorpholino propylchloride (Example 7) is obtained by reacting 1,3-dimorpholino propanol with thionylchloride.
p-Ethoxy benzylchloride (Example 9 c) is produced according to Bergmann and Sulzbacher "J. org. Chem." vol. 16, p. 85 (1951).
3,4,5-Trimethoxy benzylchloride (Example 13) is prepared by reacting 3,4,5-trimethoxy benzyl alcohol with thionylchloride and
3-(4'-Methoxy phenyl) propylchloride (1) by reacting 3-(4'-methoxy phenyl) propanol (1) with thionylchloride.
Acetyl glycolic acid chloride (Example 27 A c) is obtained according to Ghosh "J. Indian Chem. Soc." vol. 24, p. 325 (1947) from acetyl glycolic acid synthesized according to Anschuetz et al. "Ber." vol. 30, p. 467.
1-(3,4-Dibenzyloxy benzyl)-2-phenyl-3-keto piperazine (Example 42 ) is obtained by reacting 2-phenyl-3-keto piperazine with 3,4-dibenzyloxy benzylchloride. Its melting point is 108°-110° C.
3,4-Dibenzyloxy benzylchloride (Example 43) is synthesized by first producing 3,4-dibenzyloxy benzaldehyde according to the method described by Bergmann et al. "J. org. Chem." vol. 16, p. 85 (1951), reducing said aldehyde with sodium boron hydride to the corresponding alcohol, and chlorinating the resulting alcohol with thionylchloride in chloroform. Melting point of the chloride: 42°-44° C.
o-Benzyloxy benzylchloride (Example 55) is obtained in an analogous manner. Boiling point: 118° C./0.05 mm.
Diethylamino propylchloride (Example 56) is prepared by reacting diethylamino propanol with thionylchloride.
p-Chloro phenyl ethylchloride (Example 63) is synthesized according to Depuy et al. "J. Am. Chem. Soc."vol. 79, pp. 3710-11 soc." (1957) and Baddeley et al. "J. Am. Chem. Soc." 1935, p. 1820.
p-Methoxy benzylchloride (Example 69) is prepared as described in "Org. Synth." vol. 36, p. 50.
The following example describes the preparation of a compound in which R 4 and R 5 of Formulas VII to XII form an N 4 -hydroxy lower alkyl piperazine group.
EXAMPLE 62
1-(p-Chloro benzyl)-2-phenyl-4-[β-(4'-hydroxy ethyl piperazino) ethyl ] piperazine ##STR59##
The compound is obtained by reacting 1-(4'-chloro benzyl)-2-phenyl-4-(β-chloro ethyl) piperazine hydrochloride as described hereinabove in Example 21 B and C, with N 1 -(2-hydroxy ethyl) piperazine. The resulting reaction product is a yellow oil of the boiling point: 245° C./0.02 mm.
Analogous compounds in which the phenyl ring of the benzyl or phenyl lower alkyl substituent in 1-position is substituted by other substituents than chloro, as well as compounds of the 3-phenyl piperazine type or the 2- or 3-phenyl-3- or -2-keto piperazine type and which have in 4-position a hydroxy lower alkyl piperazino lower alkyl group can, of course, also be produced in a similar manner. | Novel 1,4-substituted phenyl piperazine compounds have a pronounced effect upon blood coagulation and are useful in the treatment of thrombotic diseases, especially of the arterial system. They are particularly used to inhibit thrombosis of the coronary or cerebral arteries. Examples of such compounds are 1-phenyl (lower) alkyl-2-phenyl-4-di-(lower)alkylamino (lower)alkyl piperazines, 1-phenyl (lower)alkyl-3-phenyl-4-di-(lower)alkylamino (lower)alkyl piperazines and their pharmaceutically acceptable acid addition salts. The phenyl ring in 1-position may be substituted by halogen, trifluoro (lower)alkyl, lower alkoxy, or phenyl lower alkoxy; the di-(lower)alkylamino (lower)alkyl group in 4-position may be replaced by piperidino (lower)akyl, morpholino (lower)alkyl, pyrrolidino (lower)alkyl, piperazino (lower)alkyl, or the like mononuclear nitrogen-containing heterocyclically substituted (lower)alkyl. | 2 |
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a valve system for an internal combustion engine having nonrotatable rocker shafts for mounting rocker arms or finger followers which actuate intake and exhaust popper valves.
2. Description of Prior Art
In designing a valve system or valve train mechanism for an internal combustion engine which is expected to operated at high engine speed, it is necessary to limit component deflections at the maximum rated speed. As an approximation, limiting values could comprise 0.0015 inches deflection for a rocker arm, measured at the valve tip, and 0.00075 inches of deflection of the rocker shaft, measured at the location of the rocker arm. In engines using cylindrical rocker shafts, a typical way of mounting the shafts involves placing the shaft as a slip-fit in a round mounting bore formed in the cylinder head. This causes problems because tolerances permit movement of the rocker shaft of the magnitude recited above. This is undesirable because, as noted above, any loss of stiffness due to wobble or movement of the parts of the valve system will reduce the maximum satisfactory operating speed of the valve system. The present invention mitigates this problem because it provides support for a rocker shaft at three circumferential locations which are approximately equally spaced. The rocker shaft is supported with a robustness which is essentially independent of dimensional tolerances of the rocker shaft and the mounting saddles. In conventional saddle mounting systems in which a nonrotatable rocker shaft is placed in a semicircular saddle, the diameter of the saddle must be sufficient so that the shaft neither touches solely at the bottom of the saddle, in which case the shaft would be free to rock back and forth in the presence of side loading imposed by the rocker arms and valve springs. Also, the shaft should not be pinched between the upper edges of the saddle because this will produce unwanted stresses in both the saddle and the shaft. As a result, it is exceedingly difficult to produce a semicircular saddle and shaft having appropriately sized diameters during mass production of engines. This manufacturing problem, which is present in other systems, is solved by the present invention.
SUMMARY OF THE INVENTION
A valve system for an internal combustion engine includes a plurality of intake and exhaust poppet valves, a plurality of rocker arms for actuating the poppet valves, a cylinder head having the popper valves mounted therein, at least one fixed rocker shaft for mounting the rocker arms, with the rocker shaft having a cylindrical outer surface, and a plurality of saddles formed in an outer surface of the cylinder head for nonrotatably mounting the rocker shaft, with the saddles each having opposing arcuate pads which form a generally semicircular mount for the rocker shaft. Each of the mounting pads is concave and has a radius of curvature which is greater than the outside radius of curvature of the rocker shaft, with the center of the radius of curvature of each of the pads being offset in opposite directions from the centerline of the shaft such that the shaft and the pads make line contact in a region proximate to the arc midpoint of each pad. The arcuate pads preferably have a circular form generated by an invariant radius of curvature.
According to yet another aspect of the present invention, a lubricant supply subsystem comprises a lubricant passage extending from a lubricant supply system of the engine through the concave surface of at least one of the pads at the location of the line contact between the pad and the rocker shaft, with the lubricant then passing through a port formed in the rocker shaft and into an inner volume of the rocker shaft.
According to a preferred embodiment, the rocker shaft comprises a hollow cylinder having an axially extending interior passage for conveying lubricating oil to the rocker arms.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a cylinder head having a valve system according to the present invention.
FIG. 2 is a partially schematic representation of a rocker shaft mounting system according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
As shown in FIG. 1, a valve system for an internal combustion engine includes a multitude of components which are attached to cylinder head 10. In this case, each cylinder is serviced by two intake valves 12 and a single exhaust poppet valve 14. Each pair of intake valves 12 for a given cylinder is actuated by a single intake rocker arm 17, which is bifurcated and which contacts both of intake valves 12 for a single cylinder. Each of intake rocker arms 17 is driven in conventional fashion by means of a pushrod (not shown) which extends up from a camshaft located in a lower part of the engine. Intake rocker arms 17 are mounted upon intake rocker shaft 16, which is shown with greater clarity in FIG. 2.
Exhaust valves 14 are driven by exhaust rocker arms 19, which are actuated by means of secondary pushrods 25 which extend across the top of the cylinder head between exhaust rocker arm 19 and intermediate rocker arm 21. The sole function of intermediate rocker arm 21 is to act as a bellcrank between secondary pushrod 25 and a primary pushrod (not shown) extending between intermediate rocker arm 21 and the camshaft.
As is readily understood by those skilled in the art, the present system causes considerable side loading on both intake rocker shaft 16 and exhaust rocker shaft 18. As noted above, it is necessary to maintain precise mounting geometry of both of the rocker shafts so as to maintain precision operation of both intake and exhaust valves, particularly during higher engine speeds. This precise geometry is promoted by the structure in FIG. 2. A plurality of saddles 20 is formed in the upper surface of cylinder head 10. Saddles 20 provide a means for nonrotatably mounting intake rocker shaft 16 and exhaust rocker shaft 18. Each saddle has a pair of arcuate pads 22 and 24. Arcuate pad 22 has a concave surface 22a, whereas arcuate pad 24 has a concave surface 24a. Both of these concave surfaces may be formed by a longitudinal pass of a forming tool such as a milling cutter or other type of cutter capable of producing a circular surface. Arcuate pad 22 has a radius R 22 and arcuate pad 24 has a radius R 24 . These radii of curvature are, in this case, equal, and both have a value greater than the outside radius of rocker shaft 16.
As seen in FIG. 2, center C 1 of arcuate pad 22 is offset from the center lines C 3 and C 4 of rocker shaft 16 such that the contact patch between the outer surface of rocker shaft 16 and concave surface 22a is a line contact occurring at location L 22 which is the arc midpoint of concave surface 22a. Similarly, center C 2 of arcuate surface 24a is offset in an opposite direction from the center line of shaft 16 to achieve the line contact labeled L 24 . As is the case with L 22 , line contact L 24 is situated 45° from the vertical centerline of rocker shaft 16. Because contact between saddle 20 and shaft 16 is two lines L 22 and L 24 , situated at the arc midpoints of arcuate pads 22 and 24, shaft 16 may be reliably, repeatably, and robustly placed in its desired position--a position which may be maintained largely independent of manufacturing tolerance stackup. This obviates the problems encountered with other mounting systems in which engineers and engine builders attempted to keep the outside diameter of a shaft, such as shaft 16, closely matched to the inside diameter of a bed plate or saddle such as saddle 20. Such a scheme was often destined for failure because of the tendency for the shaft to either be positioned tightly against the bottom of the saddle or at the top edges of the saddle. With the rocker shaft at the bottom, the shaft would tend to rock in the saddle; when wedged at the top of the saddle, the rocker shaft and its fastening system could induce excessive stress in both the saddle and the rocker shaft itself.
Each of rocker shafts 16 and 18 are maintained in their respective saddles by means of retaining bolts 34 and clamps 36. Each of bolts 34 has a load bearing surface 34a in contact with clamp 36, which itself has an arcuate contact surface 36a providing contact with the outer surface of rocker shaft 16. Fastener 34 passes through relief groove 26, which is milled, of formed in any other acceptable manner, in the lower surface of saddle 20. The combination of the arcuate engagement of clamp 36 with shaft 16 as well as engagement of shaft 16 with arcuate surfaces 22a and 24a solidly mounts shaft 16 to cylinder head 10. Those skilled in the art will appreciate in view of this disclosure that the contact pattern between rocker shaft 16 and clamp 36 need be only a line contact on one side of fastener 34 in order to securely fasten the rocker shaft to saddles 20. Those skilled in the art will further appreciate, in view of this disclosure, that clamps 36 may be located precisely by bolts 34 by piloting clamps 36 upon the upper portions of the shanks of bolts 34. Clamps 36 not only maintain rocker shafts 16 in their saddles, but also provide thrust surfaces for maintaining the various rocker arms in their desired axial locations.
The present cylinder head advantageously uses bolt bosses 38, through which cylinder head bolts 40 pass, for the dual purpose of providing a place for saddles 20 along with threaded bores 35 for fasteners 34.
According to another aspect of the present invention, cylinder head lubricant passage 28 provides lubricant, in this case, engine oil, through port 30 formed in intake rocker shaft 16. After flowing through port 30, lubricant flows into bore 32, which forms the interior of rocker shaft 16. Lubricant is allowed to flow through bore 32 and then through suitably located outlet ports (not shown) so as to lubricate intake rocker arms 17. Exhaust rocker shaft 18 has a similar axially directed bore for the purpose of providing oil to exhaust rocker arms 19.
While the invention has been shown and described in its preferred embodiments, it will be clear to those skilled in the arts to which it pertains that many changes and modifications may be made thereto without departing from the scope of the invention. For example, the present invention may be employed with overhead camshaft engines having followers which are journaled to a common rocker shaft. | A valve system for an internal combustion engine with multiple intake and exhaust valves driven by rocker arms includes a fixed, nonrotatable, rocker shaft for mounting the rocker arms, with the rocker shaft being mounted in saddles formed in an outer surface of the cylinder head. Each of the saddles has opposing pads forming a generally semicircular mount for the rocker shaft, with the mounting pads being offset in opposite directions such that the rocker shaft and the pads make line contact in a region proximate the arc midpoint of each pad. | 5 |
The present invention relates generally to the field of four-layer, latching semiconductor devices, and particularly to methods for controlling the conduction characteristics of such devices by modulating the voltage applied to the gate electrode of a MOSFET portion of the device.
BACKGROUND OF THE INVENTION
The development of power MOSFET's was at least in part motivated by the objective of reducing the control current required by power bipolar devices during forced turn-off. In bipolar devices the injection of minority carriers into their drift region reduces the resistance to forward current flow. These devices are capable of operation at appreciable current densities, but are relatively inefficient as a consequence of the large currents required during device turn-on and turn-off.
In contrast, the gate structure of the power MOSFET has a very high steady-state impedance. This allows control of the device by a voltage source, since only relatively small gate drive currents are required to charge and discharge the input gate capacitance. Unfortunately, the ease of gating the power MOSFET is offset by its high on-state resistance arising from the absence of minority carrier injection. Hence, a combination of low-resistance bipolar-type current conduction with MOS gate control would provide the desired features of high operating forward current density and low gate drive power.
Referring to the cross-sectional illustration of FIG. 1, a device known as an insulated gate bipolar transistor (IGBT) illustrates one approach to combining these features. In this type of structure most of the forward current flow occurs between the emitter and collector terminals of the vertical PNP bipolar transistor portion of the device. The on-state losses of the IGBT at high voltages are significantly less than those of power MOSFET's due to the injection of minority carriers (electrons) into the N-base drift region.
As shown in FIG. 2, a regenerative device known as MOS-controlled thyristor (MCT) exhibits less forward voltage drop than does the IGBT. This P-N-P-N structure can be regarded as two transistors--an upper NPN transistor and a lower PNP transistor--that are internally connected in such a fashion as to obtain regenerative feedback between each other. Specifically, a thyristor may be considered as a combination of PNP and NPN bipolar transistors connected such that the base of each is driven by the collector current of the other. Once the thyristor is turned on via the gate electrode such that the requisite transistor turn-on current is supplied each transistor then drives the other into saturation. At this juncture the thyristor is no longer under the control of its gate electrode and continues to operate even in the absence of gate drive current--a phenomenon known as regenerative latch-up. Although the large current flow characteristic of regenerative on-state operation may be extinguished by appropriate modification of the gate voltage, the current produced by the MCT may not be adjusted (i.e., "fine-tuned") during regenerative operation through modulation of the gate voltage.
Since thyristors are often used in high-power switching applications, the maximum turn-off current level is generally of considerable importance. The MCT device of FIG. 2 is turned off by reversing the polarity of the applied gate voltage so as to eliminate the accumulation layer at the surface of the N-region embedded between the P and P+ regions underlying the gate. In this way a p-channel field-effect transistor (FET) within the device forms an active short circuit between the N+ cathode and P-base regions. The device will cease regenerative operation when the short-circuit current increases to the extent that the voltage across the N+/P junction falls below 0.7 V. Unfortunately, the maximum current which can be switched off by the MCT markedly decreases with increasing anode voltages at elevated temperatures. As a consequence, the current handling capability of the MCT has proven to be inadequate for particular circuit applications.
FIG. 3 depicts a four-layer semiconductor structure, generally termed a MOS gated emitter switched thyristor (EST), also designed to operate in a regenerative mode. When the gate voltage is at the cathode potential the device is in a forward blocking mode with the anode voltage supported across junction J1. The device is turned on by applying a positive bias to the gate to create a channel at the surface of the P-base region. As shown in FIG. 3, the regenerative thyristor portion of the device latches up when the junction between the N+ floating emitter and the P-base becomes forward biased. Regenerative on-state operation is extinguished by reducing the gate bias to zero, effectively disconnecting the emitter from the cathode. Again, however, current flow during on-state operation can be fine-tuned by modulation of the voltage applied to the gate electrode only until the breakdown voltage of the lateral MOSFET is reached. Because the channels of the MOS devices inherent within conventional EST structures are relatively short, the breakdown voltages thereof are typically less than 20 volts.
In addition, the N+/P junction of the conventional EST shown in FIG. 3 does not become reverse biased until the regenerative action of the main thyristor is sufficiently attenuated. It follows that the lateral MOSFET at the surface of the structure is prone to break down during high-voltage device deactivation as a consequence of supporting the large junction voltage. Moreover, the elevated hole current through the cathode which arises during turn-off of the device may induce undesired regenerative operation within a parasitic thyristor (see FIG. 3).
Accordingly, a need in the art exists for an emitter switched thyristor which:
(i) is disposed to be turned off rapidly (i.e., in less than 1 microsecond) without accompanying parasitic latch-up, and which
(ii) allows the current provided thereby to be fine-tuned under gate control during regenerative on-state operation.
SUMMARY OF THE INVENTION
The present invention addresses the foregoing objectives by providing an improved emitter switched thyristor structure having on-state current saturation capability and a remote turn-off electrode for reducing for the time required to terminate operation in a regenerative mode. The improved thyristor structure includes anode and cathode electrodes, with the remote electrode being connected to the cathode electrode. A multi-layer body of semiconductor material has a first surface and includes regenerative and non-regenerative portions each operatively coupled between the anode and cathode electrodes. The regenerative portion includes adjacent first, second, third and fourth regions of alternating conductivity type arranged respectively in series. Electrical contact is made between the remote electrode and the second region, as well as between the anode electrode and the fourth region.
The inventive thyristor is turned on by applying an enabling voltage to an insulated gate electrode disposed adjacent the first surface such that a conductive channel is created in the non-regenerative portion via modulation of the conductivity therein. The device may be operated in a saturation mode, in which control is maintained over anode current despite latch-up of the regenerative portion of the device, by reducing the applied gate voltage such that the resistance of the conductive channel in the non-regenerative portion limits the limits the current flow. Termination of regenerative operation is initiated by applying a non-enabling voltage to the gate electrode so as to extinguish channel conductivity within the non-regenerative portion as well as within the third region of the regenerative portion. The remote electrode collects any charges remaining in the second region of the regenerative portion subsequent to application of the non-enabling voltage and thereby expedites turn-off of the inventive thyristor.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional objects and features of the invention will be more readily apparent from the following detailed description and appended claims when taken in conjunction with the drawings, in which:
FIG. 1 is a cross-sectional illustration of a conventional insulated gate bipolar transistor (IGBT) device.
FIG. 2 shows a prior art P-N-P-N regenerative semiconductor device generally known as a MOS-controlled thyristor (MCT).
FIG. 3 depicts a conventional implementation of a four-layer MOS gated emitter switched thyristor (EST) semiconductor device.
FIG. 4 shows a cross-sectional representation of a preferred embodiment of the inventive emitter switched semiconductor thyristor device having on-state current saturation capability.
FIG. 5 shows a simplified perspective view of the improved thyristor in which, for purposes of clarity, the oxide and metallization layers above the substrate surface have been omitted from view.
FIG. 6 shows a cross-sectional representation of an alternate preferred embodiment of the present invention having current saturation capability and a remote electrode for improving device turn-off characteristics.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 4, there is shown a cross-sectional representation of a preferred embodiment of the inventive emitter switched semiconductor thyristor device 100 having on-state current saturation capability. As is discussed hereinafter, the on-state current produced by the inventive thyristor device 100 may be controlled by modulation of the voltage applied to a gate terminal 105 even during operation in a regenerative mode. In order to simplify explanation only a single segment of the inventive thyristor 100 is depicted in FIG. 4. Specifically, by forming the mirror image of the thyristor segment shown in FIG. 4 about reference axes A and B a multi-section device may be created. The thyristor 100 includes a body of semiconductor material 110 having a four layer or regenerative portion 114 constituted by a floating emitter region 116 of N+ conductivity material, and by a base region 120 of P conductivity material forming a first PN junction 124 with the floating emitter 116. A third layer of the regenerative portion of the thyristor device 100 is identified as a drift region 130 consisting of N- semiconductor material adjacent to and forming a second PN junction 134 with the base region 120. As shown in FIG. 4, the semiconductor body 110 is bounded by a substantially planar upper surface 140 defined in part by the uppermost portions of the floating emitter 116, base 120 and drift 130 regions. A set of reference coordinates are included in FIG. 4 and are used in the following description to specify direction.
The drift region 130 includes an optional buffer layer 150 of N-type semiconductor, and separates the base 120 from a fourth or P+ anode layer 158. Adjacent to the four layer, regenerative portion 114 is a three layer, non-regenerative structure 166 comprised of a tri-component cathode region 172, the drift region 130, and the anode region 158. The cathode region 172 includes a well structure consisting of diffusions of P and P+material 178 and 184, with an N+diffusion 190 disposed within the well defined by diffusions 178 and 184. Ohmic contacts exist between the lower surface of anode layer 158 and an anode electrode 192, as well as between the upper surface 140 of the P+ and N+diffusions 184 and 190 and a cathode electrode 196.
FIG. 5 shows a simplified perspective view of the improved thyristor 100 in which, for purposes of clarity, the oxide and metallization layers above surface 140 have been omitted from view. Each region of the regenerative 114 and non-regenerative portions 166 of the improved thyristor 100 forms an elongated segment in a Z-direction perpendicular to the X-Y plane of FIG. 4. As shown in FIG. 5, the P-base 120 extends in the X-direction and merges with the P+diffusion 184 in a plane P lying in the Y-Z coordinate plane. In this way an electrical connection is formed between the P-base 120 and the cathode electrode 196 coupled to the P+diffusion 184.
Again referring to FIG. 4, the gate terminal 105 electrically contacts upper and lower gate electrodes 208 and 212. A thin oxide layer 216 insulates the lower gate electrode 212 from the N+diffusion 190, P diffusion 178 and drift region 130 so as to form an N-channel enhancement mode MOS field-effect transistor 224. The thickness of the thin oxide layer 216 is typically chosen such that an inversion layer may be formed in the P-type diffusion 178 and base region 120 upon application of a typical gate turn-on bias to the electrode 212. For example, for a thin oxide thickness of 500 angstroms a gate voltage on the order of 5 to 15 volts will lead to creation of a conductive channel within the P-type diffusion 178.
The upper gate electrode 208 serves to improve uniformity in the electric field within the portions of the drift region 130 and floating emitter 116 over which it is positioned. As shown in FIG. 4, the upper electrode 208 is insulated from the drift region 130 and floating emitter 116 by a thick oxide layer 222. The thick oxide 222 is dimensioned so as to be able to support large voltages between the gate electrode 208 and floating emitter 116 during operation in an on-state saturation mode described below. Accordingly, the thickness of oxide layer 222 is generally selected to be approximately ten times that of the thin oxide layers (e.g. 5000 angstroms) in order to avoid oxide breakdown during saturation-mode operation.
With the cathode electrode 196 and gate terminal 105 held at the same potential the thyristor 100 is in a forward blocking mode. In the blocking mode any voltage differential between the anode and cathode electrodes 192 and 196 is primarily supported by the PN junction 134. The device is initially actuated by applying the requisite turn-on voltage to the gate terminal 105. The subsequent formation of a conductive channel at the surface of the P-type diffusion 178 proximate the thin oxide 216 allows electrons to be injected from the N+region 190 into the drift region 130. At these low current levels the thyristor device 100 operates similarly to the conventional IGBT (Insulated Gate Bipolar Transistor) shown in FIG. 1. In IGBT mode operation the current flow through the regenerative portion 114 of the device 100 has not yet become self-sustaining (i.e., latched-up), and hence the anode current remains dependent on the magnitude of the applied gate voltage.
The electrons flowing from the N+region 190 into the drift region 130 serve as base current for the PNP transistor inherent within the four layer regenerative portion 114. When a sufficient voltage is applied to the anode electrode 192 the resulting current flow is adequate to induce regenerative thyristor action (i.e latch-up) within the four layer portion 114. The onset of regenerative action (on-state) is precipitated by the flow of hole current laterally through the base 120 in the Z direction perpendicular to the plane of FIG. 4. The hole current then crosses into P+diffusion 184, and is collected by the cathode 196. During on-state operation the electrons and holes injected into the drift region 130 serve to lower the resistance thereof, thereby increasing the efficiency of the device 100.
In order to facilitate device turn-on the sheet resistivity of the base 120 and length of the emitter 116 in the Z direction are selected to be such that the hole current develops the potential (≃0.7 Volts) required to forward bias the PN junction 124. Specifically, the floating emitter 116 will typically have a length of 20 microns while the sheet resistivity of the base 120 is generally 3000 ohms per square. The drift region 130 is doped at 10 14 /cm 3 and such that carrier lifetimes therein are on the order of 1 microsecond. It is noted that the turn-off time of the device 100 is affected by the drift region carrier lifetime. Accordingly, the drift region lifetime may be modified to meet specified turn-off time requirements.
As was discussed in the Background of the Invention, in conventional semiconductor thyristor devices the current flow between the anode and cathode becomes independent of the applied gate voltage subsequent to the onset of thyristor action. That is, once regenerative operation has commenced the gate terminal effectively becomes decoupled from the remainder of the device. It follows that the gate voltage may be allowed to float or be reduced to the cathode potential without affecting anode current flow. In contrast, the inventive thyristor device 100 is configured to facilitate control of the cathode current through modulation of the voltage applied to the gate electrode 105 even after latch-up of regenerative portion 114.
Specifically, the MOS transistor 224 may be placed in a current saturation mode by reducing the voltage applied to gate terminal 105 to approximately the threshold voltage required to create an inversion layer at the surface of P-type diffusion 178. This causes the inversion layer to become highly resistive at the surface of the P-type diffusion 178 proximate the drift region 130 without extinguishing the thyristor current produced by the regenerative portion 114. Since the resistance of the pinched-off channel within P-type diffusion 178 will be dependent upon the applied gate voltage, the flow of electrons from the N+diffusion 190 into the drift region 130 may be controlled by modulation of the gate voltage. Hence, during saturation-mode operation the electron current through the anode 192 is made a function of the applied gate voltage despite thyristor-mode operation of the regenerative portion 114.
As may be appreciated from the foregoing, the range of anode currents supported during saturation-mode operation is dependent upon the magnitude of the voltage applied to gate terminal 105. In particular, lowering the differential between the applied gate voltage and the MOS threshold voltage reduces the anode current in existence when the magnitude of the anode voltage is made sufficient to induce latch-up of the regenerative portion 114. This is the minimum anode current supported during saturation-mode operation. At high anode voltages the electron current through the anode 192 is dominated by the thyristor current of regenerative portion 114, and as a consequence the maximum saturation-mode anode current essentially depends upon the maximum applicable anode voltage. (i.e., upon the maximum voltage which may be supported between the drift region 130 between N+floating region 116 and P diffusion 178). Since the drift region 130 will typically be doped so as to be able to withstand electric fields on the order of 1×10 5 to 2×10 5 V/cm, and since the potential difference existing between the floating emitter 116 and P diffusion 178 during saturation-mode operation will generally range from 50 to 1000 volts, the drift region 130 will usually be dimensioned to extend approximately 5 to 50 microns from the N+floating region 116 to P diffusion 178. It follows that during saturation-mode operation the anode current swing supported by the thyristor device 100 may be most conveniently controlled by varying the minimum saturation-mode anode current through adjustment of the differential between the applied gate voltage and the threshold voltage of the MOS transistor 224.
When it is desired to terminate thyristor action within the regenerative portion 114 of the device 100 the voltage impressed on the gate electrode 105 is reduced to zero. The surface of the P-type region 178 will preferably be sufficiently narrow (e.g., 2 to 3 microns in the X direction) that reducing the voltage applied to gate electrode 212 will quickly extinguish the conductive channel within the MOS transistor 224, thereby rapidly diminishing regenerative thyristor action.
As may be described with reference to FIG. 3, the structure of conventional EST devices creates a predisposition for parasitic latch-up during turn-off. Specifically, reducing the applied gate voltage in order to initiate deactivation of the device induces a loss of channel conductivity between the N+cathode diffusion and the floating emitter, thereby decoupling the floating emitter from the cathode. The forward bias across the PN junction between the P-base and floating emitter then diminishes as regenerative activity subsides, and an excess hole concentration develops proximate the floating emitter as fewer electrons are injected therefrom into the base. The requirement of charge neutrality forces these holes to the cathode via the P+diffusion, thus resulting in a spike of hole current proximate the PN junction between the diffusions underlying the cathode. If of sufficient magnitude, the current spike may forward bias this PN junction and precipitate latch-up of a parasitic thyristor consisting of the N+diffusion 190 together with a PNP transistor formed by the diffusion 184, drift region 130 and anode layer 158.
The potential of parasitic latch-up during turn-off is reduced within the inventive thyristor 100 as a consequence of the aforementioned merger (FIG. 5) between the base 120 and P+diffusion 184. More specifically, during turn-off of the thyristor 100 holes present within the base 120 will migrate therein normal to the plane of FIG. 4 until encountering the P+cathode diffusion 184 rather than traverse the higher impedance path through drift region 130 to the diffusion 184. Current flow in the vicinity of the PN junction between the diffusions 184 and 190 is thus minimized, and the probability of a turn-off current spike forward biasing this junction and precipitating parasitic latch-up is correspondingly reduced.
FIG. 6 shows an alternate preferred embodiment of the inventive thyristor device 100' designed to reduce the potential of parasitic latch-up during both on-state operation and during turn-off. The thyristor devices 100' and 100 are structurally identical except within the regenerative region 114 proximate the axis A (FIG. 4). Specifically, in the thyristor device 100' a remote electrode 234' is directly coupled to the surface 140' of the P-base 120'. Additionally, in the embodiment depicted in FIG. 5 the drift region 130' is not interposed between the P-base region 120' and the axis of symmetry A'.
During on-state operation of the device 100' a substantial percentage of the anode current flows vertically through the regenerative portion 114', since it is in this region where the forward bias across PN junction 124' allows a large number of electrons to be injected into the drift region 130' from the floating emitter 116'. Nonetheless, within the non-regenerative region 166' the PNP transistor comprising the diffusion 184', drift region 130' and anode layer 158' also contributes to the on-state current flow. At very high anode current densities (e.g. 1000 A/cm 2 ) it is possible that the parasitic thyristor described above (i.e., PNP transistor in region 166' and N+diffusion 190') will latch up. Through bifurcation of the hole current between the electrodes 194' and 234' the thyristor 100' reduces the likelihood of parasitic latch-up during on-state operation by diminishing the current density proximate the PN junction between the diffusions 184' and 190'.
The remote electrode 234' also serves to expedite turn-off of the device 100' relative to conventional EST structures by facilitating charge removal from the base 120' upon reduction in the potential applied to the gate electrode 105'. As shown in FIG. 3, the only manner in which holes can be drawn from the base region of the conventional EST device depicted therein is through the cathode terminal. It follows that holes present in the regenerative portion proximate the floating emitter must traverse the entire P-base region as well as the P+diffusion in order to be collected by the cathode.
Referring to FIG. 6, the remote electrode 234' serves to reduce any excess hole concentration developing in the base 120' during turn-off of the inventive thyristor device 100'. Specifically, holes present within the regenerative portion 114' at the time of turn-off will migrate along a low-impedance path therein to the remote electrode 234' rather than through the drift region 130' to the cathode electrode 196'. This eliminates the flow of excess holes from the base 120' through the cathode region 172', and hence minimizes the likelihood of undesired parasitic latch-up.
While the present invention has been described with reference to a few specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims. Specifically, thyristor devices incorporating the teachings of the present invention may be embodied in semiconductor structures which differ from that depicted in FIG. 4. For example, the cathode region need not be realized using the specific arrangement of diffusions specified herein. Those skilled in the art may be aware of other structures for implementing the non-regenerative portion of the inventive thyristor. Similarly, in the preferred embodiments set forth herein the floating emitter regions 116 and 116' will preferably respectively overlap the P-base regions 120 and 120' in the drift region 130' by less than one micron in order to enable the inventive thyristors 100 and 100' to support relatively high forward blocking voltages. In alternative embodiments of the present invention other criteria may be used as a basis for formulating the relative dimensions of specific constituent layers. | An emitter switched thyristor structure providing on-state current saturation capability is disclosed herein. The thyristor structure includes anode and cathode electrodes, and a remote electrode connected to the cathode electrode. A multi-layer body of semiconductor material has a first surface and includes regenerative and non-regenerative portions each operatively coupled between the anode and cathode electrodes. The regenerative portion includes adjacent first, second, third and fourth regions of alternating conductivity type arranged respectively in series, wherein the remote electrode is in electrical contact with the second region and the anode electrode is in electrical contact with the fourth region. The emitter-switched thyristor is turned on by applying an enabling voltage to an insulated gate electrode disposed adjacent the first surface such that a conductive channel is created in the non-regenerative portion via modulation of the conductivity therein. The device may be operated in a saturation mode by reducing the applied gate voltage such that the conductive channel in the non-regenerative portion becomes pinched off. Termination of regenerative operation is initiated by applying a non-enabling voltage to the gate electrode so as to extinguish channel conductivity within the non-regenerative portion as well as within the third region of the regenerative portion. The remote electrode collects any charges remaining in the second region of the regenerative portion subsequent to application of the non-enabling voltage and thereby expedites turn-off of the thyristor device. | 7 |
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates in general to door operating devices and, more particularly, to an electronically actuated door operator incorporating certain new and useful improvements for controlling door opening in both normal and emergency directions.
The present invention constitutes an improvement of Catlett U.S. Pat. No. 4,045,914, entitled Automatic Door Operator. The operator disclosed therein is the type having an electrical prime mover and gear train for driving a door open by means of a driving shaft, there being a spiral leaf spring surrounding the driving shaft which is wound for storing energy during door opening operation. The operator is configured to provide for normal opening of the door in a single given direction rather than being of an interchangeable character for installations requiring the swinging of a door for normal opening in an opposite direction or for both directions. Accordingly, such operator is manufactured for a given type of door installation rather than being of a universal character.
It is an object of the present invention to provide a door operator of the present invention which is of an interchangeable, universal character for providing for automatic opening of doors which are not only intended for either left hand or right hand swing but also for both left and right hand swing.
It is an object of the present invention to provide a door operator of electromechanical character which is uniquely adapted for utilization with various types of doors of the swing-mounted type, such as center pivot, butt hinge, or offset pivot mounting.
It is another object of the present invention to provide a door operator of the character stated which is automatic in operation, being markedly compact.
It is a further object of the invention to provide a door operator of the character stated which can be either mounted within the header portion of a door frame during installation or which may be utilized with existing door constructions without necessitating expensive modification and reconstruction.
It is a still further object of the invention to provide an automatic door operator of the character stated which provides not only normal automatic opening of a door but also readily and safely permits emergency or so-called panic opening of the door.
It is a further object of the present invention to provide an automatic door operator of the character stated including a motion transmission system allowing door movement during panic opening without interference with a prime mover of the system, and which also provides automatic disabling of the prime mover in the event the door is opened under panic conditions.
It is a still further object of the present invention to provide an automatic door operator which can be rapidly configured or reconfigured for providing operation of various types of swing-mounted doors.
It is a still further object of the present invention to provide an automatic door operator of the character stated which permits convenient adjustment of the limits of door movement for both normal and panic opening thereof.
It is a still further object of the present invention to provide an automatic door operator of the type stated which embodies a permanent magnet type of motor adapted to provide dynamic braking action upon door closing consequent to spring developed power for closing the door, and wherein energizing of the motor is not required for closing the door.
It is a further object of the present invention to provide an automatic door operator of the character stated which is most economically manufactured and configured for various types of swing mounted doors, the elements of which operator are designed for quiet, smooth, low friction operation conducting to longevity of unimpaired operation; which is configured to provide extreme duration and reliability of usage; and which is extremely versatile in the door control art in being adapted for activation by any of the various remotely located control devices.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevation of a door which is swing mounted in the header of a door frame incorporating a door operator constructed in accordance with and embodying the present invention.
FIG. 2 is a top plan view in partial section of the door header and door operator located therein, as taken generally along line 2--2 of FIG. 1, and illustrating the door operator in operative position.
FIG. 3 is a vertical longitudinal sectional view taken along line 3--3 of FIG. 2.
FIG. 4 is a vertical transverse sectional view taken along line 4--4 of FIG. 2.
FIGS. 5-7 are each horizontal longitudinal sectional views of an embodiment of the door operator, taken generally along line 5--5 of FIG. 3, configured for normal left hand swing opening of the door.
FIGS. 8-10 are each horizontal longitudinal sectional views taken similarly along line 5--5 of FIG. 3, of an embodiment of the door operator configured for normal right hand swing opening of a door.
FIGS. 11-13 are similarly horizontal longitudinal sectional views, again taken generally along line 5--5 of FIG. 3, and illustrating the door operator configured for both right hand and left hand normal swing opening of the door.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now by reference characters to the drawings which illustrate the preferred embodiments of the present invention, with specific reference to FIGS. 1-4, A generally designates a door operator of the invention. Door operator A is shown, merely for purposes of illustration, as mounted within the header or upper portion 14 of a door frame 15 having a door 16 which is swing mounted for opening about a hinge axis or pivot axis extending vertically through the left edge 18 of the door. The door is provided with a handle 19 of the conventional type but it is understood that in normal usage door 16 is opened automatically by operator A when a control 20 (within header 14) for the operator is actuated by a person or object approaching the door and exerting pressure upon a switch-type floor mat activating device located in front of the door as at 21. Alternatively, various other kinds of activating devices of known configuration can be utilized, such as photoelectric cells, sonic switches, mechanical switching devices, proximity detectors and the like. All such activating or actuating devices are interconnected with the control 20 which may include various relays and other circuitry for controlling power to be supplied to actuator A, as noted hereinbelow.
Referring to FIGS. 2 and 3, operator A is provided with a prime mover M constituted by a direct current, shunt wound motor which is of the permanent magnet type providing variable speed of operation in accordance with the extent to which the motor armature is energized by d.c. current.
For such motor, d.c. power can be provided, in response to operation of the switch mat or other activating means, by control 20 having circuitry in accordance with Catlett et al. U.S. Pat. No. 4,006,392 which is herein incorporated by reference. In such a circuit, a.c. power from a conventional source is converted to d.c. power by semiconductor circuitry for being provided to the armature of motor M with a polarity for causing the motor armature rotation for door opening. Further, such a control includes provision for altering the speed of the motor as the door approaches its nearly fully closed and nearly fully opened positions, respectively, as well as provision of reducing energization of motor M in the event of door blockage sensed by the circuitry for precluding damage to the motor from excessive energization. Such control also includes provision for timing certain functions, such as a pre-opening interval and a delay interval during which the door 16 remains open after having been driven open by door operator A.
It is to be understood that door 17 is merely one of various types of doors of the hinged or swing-mounted type which can be operated by operator A, including those which are mounted on center pivots, butt hinges, or offset pivots or hinges. In addition, while operator A is shown to be located within the door frame header 14, it should be understood that the actuator can be provided as a unit within a suitable enclosure intended for being mounted on a surface adjacent an existing door and frame, thus permitting an existing door to be actuated by operator A in the same or functionally equivalent manner as door 16.
In accordance with the present invention, it is to be understood that while operator A is intended for automatically driving door 16 open in response to a person or object, such as a cart, contacting the floor mat switch 21 or other activating means, the new operator is also designed to readily permit door operation in accordance with building code requirements which essentially require than an automatic door for pedestrian traffic be capable of being operated manually in the event of power failure, as well as in panic or emergency situations. Hence, handle 19 is provided whereby the door may be pushed open manually. In such installation, it is typically required that the door automatically open in one direction, the latter being designated normal, yet must be capable of being manually opened in the reverse direction in emergencies or panic situations. Recognizedly, doors are not always hinged or pivoted for normal opening always in the same direction. That is, some doors may require a normal left hand swing opening while permitting right hand swing in the panic mode; or the door may require normal right hand swing with a left hand swing in the panic mode. Further, some doors are intended to provide normally both a right hand swing (left hand panic) and a left hand swing (right hand panic). For purposes of orientation, door 16 if intended for left hand swing (right hand panic) would normally open away from the viewer but under panic conditions would open toward the viewer.
Header 14 in which door operator A is mounted includes a front and rear walls 23,24 and end walls, as at 25, as well as a floor or bottom wall 27, to provide a rectangular enclosure for accommodating the structure of operator A. The header is closed also across the top by a cover 28 or top wall of removable character for providing access to operator A and control wiring, etc.
Operator A is mounted to floor 27 of header 14 by flexible rubber mounts, as at 29, 30 and 31, which are carried by brackets, as at 33, 34 and 35, rigidly secured to floor 27 by screws (not shown). Bracket 35 which extends transversely of header 14 and includes a projection 36 which is secured to a rib 37 carried upon the inner surface of end wall 35, as by a screw 39, thereby to precisely locate the same laterally within the header 14. Each of the flexible mounts 29, 30 and 31 is secured to a transmission housing of the operator, which housing is designated in its entirety at 41, whereby the entire housing 41 is resiliently and flexibly positioned within header 14 in shock absorbing relationship without metal-to-metal contact to prevent vibration, operational noise and shock from being transmitted from the operator A to the header 14 or door frame 15, providing reliability and quietness of operation.
Motor M is in turn secured to one end of housing 41 by screws 42 which extend through a flange 43 of the motor. Referring to FIG. 3, motor M is provided with an output shaft 45 which is connected to a coaxially driven input shaft 46 of the operator by means of a flexible coupling 47. Shaft 46 is journalled within housing 47 by roller needle bearings 49 provided within a bore 51 in housing 41, with there being thrust bearings 52,52' as of wedge roller type on opposite ends of needle bearings 49. A grease seal 54 is located around shaft 46 between thrust bearings 52' and coupling 47.
Affixed to the coupling remote end of shaft 46 is a bevel gear 55 which meshes in 45° relationship with a further bevel gear 56 pinned to a shaft 57 having a longitudinal axis perpendicular to that of shaft 46 and journalled at opposite ends within needle bearings 59,60 and maintained longitudinally therein by respective thrust bearings 62,63. Shaft 57 integrally embodies a pinion 65 which meshes with a driven gear 66 connected as described later to a shaft 67 parallel with shaft 57 and also perpendicular to input shaft 46. Said shaft 57 is journalled at opposite ends within housing 41 by needle bearings 69,70 and is positioned longitudinally by thrust bearings 71,72. Shaft 67 carried a small diameter pinion 74 which in turn meshes with a relatively large diameter gear 75 which is carried by a shaft 76 journalled similarly longitudinally by thrust bearings 81,82.
Integrally formed upon shaft 76 is a pinion 83 which meshes with a main shaft driving gear 84 which is secured to a door driving shaft 86 by a key 87, with shaft 86 being journalled within housing 41 by needle bearings 88 at the lower ends and extending well below the floor or bottom wall 27 of housing 14 to present a toothed portion 86' for engagement with a spline (not shown) of a door actuating arm or structure or structure associated with the door for causing rotation about the hinge axis of a door. At its upper end, shaft 86 is journalled within heavy duty ball-type thrust bearings 90 mounted within a boss 91 of a horizontally disposed cover portion 92 of housing 41.
It may here be observed that pinions 65, 74 and 83 and gears 66, 75 and 84 respectively driven by these pinions are preferably of helically cut character for providing substantially noiseless meshing for quietness of operation of the operator.
The coupling of gear 66 to shaft 67 is accomplished by the provision of an over-riding or over-running clutch C whereby gear 66 is permitted to turn at greater velocity than shaft 67 or to be rotated in its normally driven direction in the absence of rotation of shaft 67 for purposes more fully set forth hereinbelow.
There is thus seen to be provided a gear train or transmission for permitting the rotary motion provided to input shaft 46 upon energization of motor M to be provided with a mechanical advantage and speed reduction for achieving an overall ratio of approximately 156:1 whereby the door driving shaft 86 wll be caused to rotate at a speed of preferably about 10 RPM at normal full speed of motor M.
An upper end portion 86" of the main driving shaft extends upwardly beyond cover plate 92. Carried upon said portion in co-rotating relationship and clampingly secured thereto by means of a screw 94 are three cam plates 95, 96 and 97, each having lobes and dwell portions of different arcuate extents for actuating corresponding ones of three switches 99, 100 and 101 of the roller actuator type mounted upon cover plate 92. Switch 99 is adapted to be actuated upon rotation of shaft 86 by an amount sufficient to bring the door into nearly opened disposition or so-called "back check" condition and for this purpose is interconnected with control 20 for the purpose of reducing energization of motor M to retard the speed of the door as it approaches the fully opened position. Switch 100 is adapted for actuation as the door 16 reaches its nearly fully closed position, being also connected with control 20 to cause the latter to change dynamic braking of motor M as the door approaches its nearly closed position. Switch 101 is also interconnected with control 20 and is operative only in the event that the door should be moved manually open into its so-called panic position. These switches are interconnected in accordance with the functions provided by the control circuitry of said Catlett et. al. U.S. Pat. No. 4,006,392.
In accordance with the invention, door operator A is intended to provide for automatic opening of door 16 for either normal left hand swing (right hand panic) or normal right hand swing (left hand panic) or both left and right hand swing. Therefore, cam plates 95, 96 and 97 are appropriately arranged, being each provided with lobe and dwell portions which are symmetrically oriented whereby the cam plates may be dispositioned appropriately with either face up in desired arcuate relationship upon shaft 86 for actuating corresponding ones of switches 99, 100 and 101 to provide the switching function hereinabove described, no matter whether the shaft 86 is intended to be driven clockwise or counterclockwise for either direction normal door opening movement as described above.
Secured to main drive shaft 86 by means of a key 102 is a pinion 103 which meshes with a horizontal rack gear 104. Referring to FIG. 4, said rack gear 104 is of a partially circular section, being journalled slidably within an elongated portion 105 of housing 41 for slidable movement therein in corresponding directions horizontally upon rotation in either direction of pinion 103 caused by corresponding rotation of drive shaft 86. The horizontal disposition of rack gear 104 with respect to pinion 103 when the drive shaft 86 is in a position corresponding to the door being closed is demonstrated in FIG. 5, there being a space 107 for accommodating leftward movement of rack gear 104 upon counterclockwise rotation of shaft 86. Further, the left end face of rack gear 104 is provided with a threaded bore 108 for receiving a screw, as at 109 in FIGS. 8-10, for providing an adjustable stop adapted to bear against one end wall 111 of housing 105 for limiting leftward movement of rack gear 104 in the case of the embodiment depicted in FIGS. 8-10, being unnecessary in the embodiments of FIGS. 5-7 not used in the embodiments of FIGS. 11-13.
Interconnected with the rack gear 104 is a spring assembly of replaceable, modular character configured for receiving energy from the rack gear upon shifting thereof by driving of motor M in accordance with a preselected direction of normal door opening movement, and for thereafter transferring the received energy to the rack gear for the purpose of closing the door without requiring motor M to be energizing. In FIGS. 5-7, the spring module is designated S1, in FIGS. 8-10, S2, and in FIGS. 11-13, S3. Hence, the three different spring modules S1, S2, and S3 appear to provide in effect three different operator embodiments, yet the embodiments are but variations of a single operator A of the invention which thus takes on a universal, interchangeable character.
The operator configuration of FIGS. 5-7 provides automatic operation of a door intended for normal left hand swing opening (right hand panic opening). The configuration of FIGS. 8-10 provides operation of a door intended for normal right hand swing opening (left hand panic opening). And the configuration of FIGS. 11-13 provides automatic operation for both left and right hand normal opening (and with respectively right and left panic opening).
Referring to FIGS. 5-7, operator A is provided with a spring module or assembly S1 which as a matter of generality includes a push rod 112 including a threaded end fitting 113 threaded into a bore 114 in the right end face of rack gear 104. The push rod has a tubular portion 115 extending into the center of a coiled compression spring 116 in coaxial relationship therewith over a major portion of the length of the spring being interconnected as later described with the end of the spring remote from rack gear 104.
Spring 116 is maintained in a compressed pretensioned or preloaded state within a cylindrical housing 117 which includes a threaded sleeve portion 117' which is threaded into a corresponding bore 118 of rack housing 105 and secured therein by means of a set screw 119. Housing 117 is closed at its rack remote end by a plug 120 into which is threaded a portion 121 of a rod-like extension 122 which extends adjustably inwardly of the housing 116, said threaded portion 121 having a lock nut 123 thereon for maintaining rod 122 in preselected, fixed longitudinal relationship within housing 116. The inner end of rod 122 has a threaded bore 125 in which is fitted a screw 126, the head of which extends into the bore 127 of a tubular push rod extension 115 whereby the latter is slidably disposed upon extension 122 and screw 126.
Secured to the rack remote end of push rod tubular extension 115 is a sleeve-like fitting 129 having a flange 130 of diameter nearly as great as the inner diameter of housing 116 for permitting slidable movement therein while presenting a shoulder 132 for bearing against one end of spring 115 to maintain the same in a compressed, pretensioned state such as preferably to about 450-465 pounds, with the other end of the spring bearing against a corresponding shoulder 133 of collar 117. Fitting 129 is secured to tubular push rod portion 115, as by being threaded within a bore 135 thereof but dimensioned to present a shoulder 136 adapted to bear against a corresponding shoulder 137 defined by the head of screw 126.
The latter constitutes an adjustment screw which may be screwed in or out of bore 125 whereby a predetermined incremental distance is provided between shoulders 136,137 to define the distance over which push rod 118 and its tubular portion 127 may be shifted to the left upon movement of rack gear 124 produced by rotation of drive shaft 86, as demonstrated in FIG. 6. Plug 120 is also provided with an adjustment screw 139 adjustably disposed within a bore of plug 120 to define a distance of movement between said the head of screw 139 and a corresponding rear face 140 of the flange 130 to define the distance over which rack gear 104 may be shifted to the right upon rotation of shaft 86. In this way, the arcuate extent of movement of the door in either direction from its closed position are defined and may be conveniently and precisely selected as desired for a given door. Further, such adjustments are intrinsically characteristic of spring module or means S1, whereby operator A when utilizing such module will have been configured not only for proper door opening but also for defining the limits of door movement.
Normal door opening operation by operator A when employing module S1 is shown in FIG. 6. Upon energization of Motor M by controller 20, the gear train causes rotation of door driving shaft 86 in a counterclockwise direction to cause the door to swing normally open in response to the power delivered to it by shaft 86. At the same time, rack gear 104 shifts longitudinally to the left, causing tubular push rod portion 115 to increasingly tension spring 116 whereby kinetic energy becomes stored in the spring as potential energy. Such leftward shifting continues until face 136 of fitting 129 engages the head shoulder 137 of screw 126, the position of which has been selected by the extent to which rod 122 is threaded into plug 120 and there locked by nut 123. At such engagements, shifting of rack gear 104 is stopped to define the angular extent through which the door has been permitted to swing. As said door approaches its thus deprived fully open position, switch 99, interconnected with control 20, is actuated by causing the control to reduce the energization of motor M and thus reduce its speed whereby the door speed is retarded.
At the termination of the open delay interval established by control 20, motor M is deenergized and switched into a dynamic braking mode, as is known in the motor control art.
The energy stored in spring 116 is now returned to rack gear 104 for rotating door driving shaft 86 in a direction for closing of the door. Such rotation is coupled through the gear train to motor M which is no longer energized. However, the driven motor armature produces a current which is limited by controller 20 to provide dynamic braking by the motor for limiting the speed of door closing. Even in the event of the failure of electrical power, the door thus closes in response to the energy stored in spring 116. As the door approaches its nearly fully closed position, switch 100 is actuated to retard the speed of the door by increasing the dynamic braking of motor M and the door shuts gently with the spring module and rack gear components being again as depicted in FIG. 5.
If the door should be manually pushed open in its normal moving direction as at a greater speed than it is being driven open (about 10 rpm), over-running clutch C allows normal free opening movement of the door against the tension of spring 116, even though motor M continues to operate normally.
If, while closed, there should be an emergency or panic situation, it is conceivable that an attempt could be made to manually force open the door in the direction opposite from its normal swing. In accordance with the invention, such so-called panic movement is made possible by the new operator so that there will be no unsafe situation resulting from an inability to swing the door opposite from its normal direction, as where the door normally swings inward, i.e., into a room, store, or public place, etc., yet where persons within such location might, in the event of emergency or in panic, attempt to force the door outward.
FIG. 7 illustrates such operation wherein the reverse swinging of a normal left swing door causes clockwise rotation of door driving shaft 86 for right longitudinal shifting of rack gear. Push rod 113 and its tubular portion are thus also shifted to the right, until face 140 of flange 130 contacts adjustable stop screw 139, limiting further movement and thus defining the panic swing arcuate limit of the door. At the same time, panic movement of shaft 86 causes operation of switch 101 which causes electrical power to be switched to preclude normal driving of motor M, control 20 and switch 101 being preferably so wired such that when switch 101 is actuated, the provision of power to motor M is prevented.
FIGS. 8-10 show a version of operator A configured, by the provision of a modified spring module S2, for automatically actuating a door mounted for normal right hand swinging (left hand panic). Within tubular housing 117, which is closed by a modified plug 142, there is provided a relatively short tubular push rod 143 having a terminal portion 144 threaded into bore 114 within rack gear 104. A spring 116' of the same character as spring 116 (FIGS. 5-7) is maintained in precompressed, pretensioned state, e.g., to about 450-465 pounds, by bearing at one end against a face 146 and at the other end against a face 147 of a flange 148 which is seated upon a reduced diameter portion 149 of push rod 143.
Housing 117 is secured as in the embodiment of FIGS. 5-7 so as to be quickly detachable from the rack gear housing 105 for replacement of module S2.
Extending into a bore 151 of push rod 143 is a rod 152 having one end 153 threaded into a correspondingly tapped bore 154 of plug 142 and maintained in position by a locknut 155. The other end 157 of rod 152 which is received in this bore 151 in relative slidable relationship thereto, is thus selectively positionable with respect to a face 159 at the end of bore 151 whereby push rod 143 is free to move with rack gear 104 to the right as shown in FIG. 9, upon door opening movement, being driven by motor M until face 159 engages rod end 157. Thus, rod 152 serves as an adjustable stop for limiting opening of the door.
As in the previous embodiment, energy normal during door opening is transferred to spring 116' as it is further compressed, as shown in FIG. 9 until the door reaches its fully open position, limited as above described. Energization of motor M is then discontinued, rack gear 104 is then driven to the left causing the door to be driven to its closed position by rotation of door driving shaft 86. Switches 99 and 100 operate as before.
In an emergency panic situation, operation of the door operator with spring module S2 is shown in FIG. 10, wherein left hand swinging of the door in the panic direction causes counterclockwise rotation of shaft 86, actuating switch 101 which controls the provision of power to motor M for interrupting or preventing its normal driving energization.
It is observed that bore 108 at the left end of rack gear 104 is provided with screw 109 to serve as an adjustable stop by engagement of enclosure face 111, thus limiting the extent to which the door can be swung open in the panic direction.
In all of the embodiments of door operator A, it is preferred that the gear ratio between pinion 103 and rack gear 104 be such that approximately 1.5 inches (38.1 centimeters) of shifting of the rack gear will result from 90° of rotation of door driving shaft 86.
Referring now to FIGS. 11-13 there is illustrated a door operator of the invention as incorporating yet another spring module S3, the operator being suited for providing both left and right hand normal opening, yet permitting respective right and left hand panic opening.
As shown in FIG. 10, spring module S3 includes the same tubular housing 117 secured to rack gear housing or enclosure 105 by a sleeve portion 117' having an end threaded into bore 118 of enclosure 105 and locked therein by set screw 119. The rack gear remote end of housing 117 is enclosed by previously described plug 120', there being a short rod or stop 161 disposed therein by threading of one end 162 into a tapped bore 163 of the plug and maintained in preselected horizontal relationship by locknut 153, the other end providing a face 164 for engagement as later explained.
Threaded into bore 114 rack gear 104 is a push rod 165 having a cylindrical portion 166, having a first diameter, and a reduced diameter remote portion 167 so as to define a shoulder 168. Slidably engaged upon the cylindrical portion 167 of the push rod is the sleeve portion 170 of a tubular member 171 having a bore 172 of diameter slightly greater than rod portion 167. Stop 161 extends into bore 172. A screw 173 is threaded into a bore 174 at the end of push rod portion 167 to serve as an adjustable stop, having a head 175 of diameter greater than push rod portion 167 to provide a shoulder 176 for engagement of a corresponding shoulder 177 (see FIG. 13) defined by sleeve 170.
A threaded outer portion 179 of sleeve 171 has fitted on it a flanged collar 181 to provide a peripheral seat 182 for spring 116", said collar being maintained in place relative to tubular member 171 by a locknut 183. A spacer sleeve 189 spacedly locates flanged collar 181 a preselected distance from plug 120'. The opposite end of spring 116' is seated against a similar flanged collar 185 which is spaced upon push rod portion 166 from rack gear 104 by a tubular sleeve 186. Collar 186 provides another seat 188 for the opposite end of spring 116" whereby it is compressed between flanged collars 181 and 186 in a pretensioned state, as in previous embodiments. Collar 181 and 183 are positionable upon tubular members 171 to achieve a preselected tension (i.e., preferably 450-465 pounds) within spring 116".
Referring now to FIG. 12, operation of this embodiment is illustrated for normal left hand opening of door 16 when driven by motor M. Counterclockwise rotation of door driving shaft 86 causes shifting to the left of rack gear 104. This causes pushrod 165 to cause shifting to the left of tubular member 171 by engagement of sleeve 170 with screw head 175, causing flanged collar 181 to be also drawn to the left, further compressing spring 116'. In this way, energy supplied by motor M in driving door 16 to an open position is transferred to spring 116". The door continues to open until adjustable stop screw 109 at the left end of rack gear 104 contacts housing face 111, thus depriving a fully open position of the door.
Upon deenergization of motor M, spring 116" returns its stored energy to rack gear 104 via push rod 165, causing shaft 86 to be driven clockwise and with the transmission causing rotation of motor M, now acting in its dynamic braking mode to provide controlled closing of door 16.
It is a matter of importance to observe that spring module S3 is designed to very precisely maintain door 116 in its closed position with precise tolerance in contrast with the usual backlash or play which otherwise is quite typically present in prior art door operators. For this purpose, the play is eliminated by precise adjustment of the location of housing 117 with respect to rack gear housing 105, such being achieved by loosening of set or lock screw 119 and then rotating housing 117 within the threaded bore 118 to cause shifting of housing 117 in or out of bore 118. Preferably, the length of the various elements of spring module S3 are dimensioned to provide for essentially zero play in the mechanism when there is present a slight gap 190 between spring housing 117 and gear housing 105, being approximately 0.04 inches (about 1 millimeter) whereby sufficient latitude is provided for very fine adjustment and zero positioning of the door, bearing in mind that 0.025 inches (0.64 millimeter) of play in adjustment in the rack gear mechanism may typically translate into about 2 inches (5.1 centimeters) of play at the outer end of door 16, so that such adjustment is quite accurate and precise.
When motor M is energized with reverse polarity for automatically driving door 16 open for normal right hand swing, door driving shaft 86 is caused to rotate clockwise, shifting rack gear 104 and push rod 165 to the right, as depicted in FIG. 13. Space 186 causes flanged collar 185 to shift to the right, but spacer 189 prevents rightward shifting of flanged collar 181 whereby spring 116" is caused to be further compressed, thus receiving energy from motor M as the door is driven open by further rotation of shaft 86. Also, flanged collar 181 prevents rightward shifting of tubular member 171 whereby reduced diameter portion 167 of the push rod is caused to slide relative to sleeve 170, and with movement continuing until screw head 175 contacts the end surface 164 of rod 161, thereby preventing further movement of the rack gear and limiting the arcuate extent of door opening.
Of course, when motor M is then deenergized, the energy stored in spring 116" causes leftward shifting of rack gear 104 for driving door 16 to its closed position but with motor M being in a driver mode and providing dynamic braking for controlled door closure.
During the normal actuation of the door in this manner switches 99 and 100 are actuated by the embodiment of FIGS. 11-13, and as described previously for reducing the speed by the door as noted. Panic operation of the door is also permitted by this embodiment, as will be apparent from FIG. 12, wherein the relationship of the parts during normal left swing corresponds to right hand panic swing of the door, and from FIG. 13, wherein normal right hand swing corresponds to left hand panic swing. Switch 101 is wired to control 20 in this embodiment to reverse the polarity of connected of motor M so that spring 116" is under proper control when the door closes after opening in a panic direction.
Because of the transmission arrangements of level gears and needle bearings operation of the new operator is quiet and smooth and provides reliable and fully safe operation of the door in both normal and panic modes. The virtually noiseless operation of the operator is further ensured by the use, if desired, of a liner within the spring housing 117, as shown at 190 in various embodiments.
Such liner 190 may be one of various synthetic resin materials, thermoplastics, etc., to provide a thin, low friction surface against which the spring 116, 116', 116" of any of the various spring modules S1, S2, S3 may bear in slidable relationship without metal-to-metal contact, in being preferred that such liner merely extend along substantially the entire inner surface of housing 117, providing thus no interference with the mechanical components therein.
Although the foregoing includes a description of the best mode contemplated for the invention, it should be understood that changes and modifications in the formation, construction, and arrangement and combination of the several parts of the new automatic door operator embodiments may be made and substituted from those herein shown and described without departing from the nature and principle of the invention. | A door operator of electromechanical character for utilization with swing-mounted doors is provided in a self-contained unit for mounting as a part of a door frame or for attachment to existing doors and frames. The opener has a door driving shaft mounted for rotation about a vertical axis and connectable to a door for closing and opening of the door when rotated, and a transmission interconnecting a prime mover and door driving shaft for rotation to open the door upon selective delivery of power by the prime mover. A pinion interconnected with the shaft meshes with a rack gear for shifting of the rack gear about a longitudinal axis in response to rotation of the shaft. The unit includes a module of interchangeable character having a preloaded spring and configured for the intended direction(s) of rotation of the door for opening. The spring receives energy from the rack gear upon door opening and then transfers the stored energy to the rack gear upon cessation of delivery of power by the prime mover for producing rotation of the shaft in the opposite direction to close the door while returning power to the prime mover, which is preferably an electronically driven and controlled d.c. motor. The rack gear and spring module permit rotation of the shaft also in a direction for emergency opening of the door. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority of U.S. Provisional Application No. 60/383,076, filed May 23, 2002.
FIELD OF THE INVENTION
This invention relates to pumps, and, more particularly, to pumps having highly-accurately controlled dosing.
Highly-accurate pumps are known in the prior art for repeatedly delivering doses within exacting tolerances, even at extremely low-dose volumes. For example, with reference to International Patent Application No. PCT/US00/23206, published as International Publication No. WO 01/14245 on Mar. 1, 2001, a pre-compression pump system is shown for repeatedly delivering microdoses of fluid. The pump of this design utilizes a stationary seal which bears against a moving valve stem. The stroke of the pump is defined by the length of a constant-diameter portion of the valve stem which terminates at a lower extreme defined by a plurality of circumferentially-spaced recesses. In this manner, the seal member remains in constant sealing engagement with the valve stem with fluid bypassing the sealing member via the recesses to re-charge the pump chamber. With this structural configuration, accurate control of dosing can be achieved through accurate dimensioning of the valve stem and recesses. In a different approach, U.S. Pat. No. 5,277,559, which issued on Jan. 11, 1994 to the inventor herein, a pump with a sliding seal is provided which moves, at least in part, with a valve stem that selectively controls flow through the pump.
SUMMARY OF THE INVENTION
With the subject invention, pump systems are provided which allow for highly-accurate dose control. In one embodiment, a pump system is provided which includes a pump body having a first chamber defined therein; a valve stem disposed to slide within at least a portion of the pump chamber, the valve stem having a constant-diameter stroke portion interposed between reduced-diameter portions; and at least one stationary sealing member immovably affixed to the pump body formed to sealingly engage the stroke portion of the valve stem. The sealing member is also formed to not engage the reduced-diameter portions of the valve stem. With the sealing member sealingly engaging the stroke portion of the valve stem, a portion of the first chamber of the pump body is isolated or substantially isolated from other portions of the chamber. Accordingly, fluid trapped within the first portion may be compressed and dispensed.
In a second embodiment, a pump system is provided which includes a pump body having a first chamber defined therein; a piston disposed to slide within at least a portion of the first chamber, the piston having a constant-diameter stroke portion interposed between reduced-diameter portions; and at least one stationary sealing member immovably affixed to the pump body formed to sealingly engage the stroke portion of the piston. The sealing member is also formed to not engage reduced-diameter portions of the piston. With the sealing member sealingly engaging the stroke portion, a portion of the first chamber is isolated or substantially isolated from other portions of the first chamber. Again, as with the first embodiment, fluid trapped within the first chamber can be pressurized in being dispensed.
With both embodiments, the volume of the administered dose is controlled by the stroke length, which, in turn, is a function of the dimensioning of the constant-diameter stroke portion and the dimensioning of the sealing member. Advantageously, with the subject invention, a minimal number of tolerances can be implicated in controlling dosing volume.
In third and fourth embodiments, “in-line” pump systems can be provided having an exit aperture extending along the longitudinal axis of the pump system (such as in the manner of a nasal spray). These embodiments each include a valve stem and operate in the same basic manner as the first embodiment.
These and other features will be better understood through a study of the following detailed description and accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIGS. 1-3 depict a first embodiment of a pump system formed in accordance with the subject invention herein;
FIGS. 4-6 show a second embodiment of a pump system formed in accordance with the subject invention herein;
FIG. 7 is a front elevational view of a possible external configuration of a pump system;
FIGS. 8-9 show a third embodiment of a pump system formed in accordance with the subject invention herein; and
FIG. 10 shows a fourth embodiment of a pump system formed in accordance with the subject invention herein; and
FIGS. 11A-11C are top, side and bottom views, respectively of a swirl plug which may be utilized in connection with the subject invention.
DETAILED DESCRIPTION
Pump systems are described herein having a relatively low number of dimensions critical for controlling dosing. The pump systems are particularly well-suited for use with ophthalmic medication, which can be repeatedly and accurately dosed in relatively small doses (less than or equal to 50 microliters). In manufacturing, a low number of critical dimensions translates to a small range of net inaccuracy (e.g., combined deviations within acceptable tolerances).
With reference to FIGS. 1-3, a first pump system 10 is shown in cross-section having an outer generally cylindrical wall 12 . A bulkhead 14 extends inwardly from the wall 12 to define an upper limit of a reservoir 16 . In a preferred embodiment, the reservoir 16 is not vented to atmosphere, and, thus, pressure piston 18 is provided to avoid the formation of a vacuum in the reservoir 16 . The pressure piston 18 is urged towards the bulkhead 14 by spring 20 and is responsive to reductions of fluid volume in the reservoir 16 (such as with fluid being drawn therefrom). The spring 20 is mounted onto, and acts against an end plate 22 , that is connected to the wall 12 using any technique known by those skilled in the art, such as with a snap fit. If required, and as will be recognized by those skilled in the art, venting may be provided between the wall 12 and the end plate 22 , and may be provided similarly in the further embodiments described below.
Apertures 24 are defined through the bulkhead 14 through which fluid may be drawn from the reservoir 16 . A solid disc-shaped support plate 26 is defined at the center of the bulkhead 14 , with the apertures 24 being spaced circumferentially thereabout. Splines 28 extend upwardly from the support plate 26 and between the apertures 24 , and a solid wall 30 encircles the splines 28 . The wall 30 terminates in a cantilevered tapered seal ring 32 . A lower pump chamber 34 is defined amidst the support plate 26 , the wall 30 , and the seal ring 32 , which is in fluid communication with the reservoir 16 via the apertures 24 .
Casing 36 is mounted onto the wall 30 and is formed with a cylindrical portion 37 and an upper aperture 38 . An upper pump chamber 40 is defined within the casing 36 and is in communication with the lower pump chamber 34 . A valve stem 42 is disposed within the pump chambers 34 and 40 and is urged away from the support plate 26 by a stem spring 44 . A slidable piston cap 46 extends through the aperture 38 and has annular seal members 48 in sealing contact with the cylindrical portion 37 of the casing 36 . The piston cap 46 further includes an inner annular passage 50 formed between the stem 42 and the piston cap 46 which is in fluid communication with an exit aperture 52 located at the upper extremity of the cap 46 . The stem 42 is formed with a top 54 that terminates in a tapered portion 56 shaped to be seated in, and form a seal with, the exit aperture 52 . The stem spring 44 is selected such that the tapered portion 56 is sufficiently acted on to form an acceptable seal with the exit aperture 52 .
A nozzle actuator 58 is mounted onto the piston cap 46 so as to move unitarily therewith. Passageway 60 communicates the exit aperture 52 with a discharge chamber 62 in which is located a discharge piston 64 . The discharge piston 64 includes circumferential seals 66 which prevent fluid from leaking beyond the discharge chamber 62 . The discharge chamber 62 is in fluid communication with a discharge nozzle 68 .
A stem 70 of the discharge piston 64 has a seal surface 72 formed at an end thereof which coacts with a tapered surface 74 of the actuator 58 to form a seal for the discharge chamber 62 . A discharge spring 76 urges the seal surface 72 into engagement with the tapered surface 74 . To facilitate assembly, an end 77 of the nozzle actuator 58 may be formed open so that the discharge piston 64 and the discharge spring 76 may be mounted therein and covered with a plug 78 which may be fixed using any technique known to those skilled in the art, such as with an interference fit using detents 80 .
In use, the nozzle actuator 58 is caused to be pressed downwardly, as represented by the arrow A. As such, the piston cap 46 moves unitarily with the actuator 58 , causing the top 54 to also move downwardly. Upon traversing a stroke distance S, an enlarged portion 82 of the top 54 engages the seal ring 32 , thereby sealing the lower pump chamber 34 from the upper pump chamber 40 . With further downward movement, the seal ring 32 is caused to flex outwardly (forming a seal with the enlarged portion 82 ) and the volume of the upper pump chamber 40 is decreased. With further volume decrease, the pressure of the fluid trapped within the upper pump chamber 40 increases and acts upon upper face 84 of the enlarged portion 82 . As the actuator 58 and the piston cap 46 continue downwardly, pressure builds in the trapped fluid. When pressure overcomes the biasing force of the stem spring 44 , the tapered portion 56 of the stem 42 moves downwardly and away from the cap 46 , thereby exposing the exit aperture 52 (FIG. 2 ). Fluid then is forced into the discharge chamber 62 where pressure therein is increased until the seal members 66 are forced rearwardly against the force of the discharge spring 76 . As a result, discharge nozzle 68 is exposed and pressurized fluid from the discharge chamber 62 is dispensed therefrom. When the enlarged portion 82 goes through, and beyond, the seal ring 32 , the upper pump chamber 40 comes into fluid communication with the apertures 24 via the lower pump chamber 34 , thereby reducing fluid pressure in the upper pump chamber 40 (FIG. 3 ). This allows the stem spring 44 to urge the stem 42 upwardly into sealing engagement with the exit aperture 52 . With the exit aperture 52 closed, fluid pressure in the discharge chamber 62 decays with fluid being dispensed through the discharge nozzle 68 , allowing the discharge spring 76 to shut off the discharge nozzle 68 . The release of the actuator 58 allows the stem spring 44 to return the stem 42 and the piston cap 46 to their original rest positions. As the enlarged portion 82 passes upwardly through the seal ring 32 , it creates a transient vacuum sufficient to draw a volume of fluid through the apertures 24 equal to the amount dispensed. The pressure piston 18 assists the transient vacuum in urging fluid into the lower pump chamber 34 . This assures total fluid replacement. The volume of the reservoir 16 is decreased in response to the fluid which is drawn therefrom as the pressure piston 18 is pushed upwardly responsively by the spring 20 .
The size of the dose dispensed by the pump system 10 is basically a function of four critical dimensions of the pump system 10 . Particularly, the length of the enlarged portion 82 (“x”); the length of flat surface 83 of the seal ring 32 (“y”); the diameter of the enlarged portion 82 (“d”); and, the inner diameter of the casing 36 along cylindrical portion 37 (“z”). By minimizing the tolerances of these four dimensions, high-level of control over doses administered by the pump 10 can be achieved. As will be appreciated by those skilled in the art, dimension “y” (i.e., the flat surface 83 ) can be made so small (0.005 in) that dimensional variation may be practically zero and three dimensions actually control dosage of the pump system 10 (e.g., the flat surface 83 could be made as a small radius making this dimension a point contact with neglible width).
With reference to FIGS. 4-6, a second embodiment of a pump system is depicted therein in cross-section and generally designated with the reference numeral 100 . Many of the components of the pump system 100 are the same as, or similar to, that of the pump system 10 described above, and are designated with like reference numerals herein. The pump system 100 , like the pump system 10 , is dependent upon four critical dimensions. The discussion below will focus on the differences from the pump system 10 in structure and operation.
A pressure piston 18 ′ is provided which is spring-biased by a spring 20 in the same fashion as the pressure piston 18 . However, the pressure piston 18 ′ is shown to have a generally planar surface in contact with the reservoir 16 , whereas the pressure piston 18 is formed with a tapered portion. The shape of the pressure piston 18 , 18 ′ is preferably selected to match the shape of the corresponding bulk head. In FIG. 1, the bulkhead 14 is formed with a tapered portion, whereas in FIG. 4, a bulkhead 14 ′ is provided which is generally planar. In this manner, the pressure piston 18 , 18 ′ may efficiently urge fluid out of the reservoir 16 .
A central disc-shaped support plate 26 ′ is formed in the center of the bulkhead 14 ′ with apertures 24 ′ being formed circumferentially thereabout. An inner annular wall 28 ′ extends from the support plate 26 ′, located radially inwardly of the apertures 24 ′. The wall 28 ′ terminates in a seal ring 32 ′. A locator pin 102 may also be provided which extends upwardly from the center of the support plate 26 ′ to provide support for the spring 44 . A lower pump chamber 34 is defined admist the support plate 26 ′, the wall 28 ′ and the seal ring 32 ′.
The pump system 100 utilizes a piston 42 ′ which has a different configuration from the stem 42 of the first embodiment. The piston 42 ′ is disposed to extend through an aperture 38 of casing 36 so as to be slidable relative thereto. Piston seals 48 ′ provide a seal against the cylindrical portion 37 of the casing 36 during sliding movement of the piston 42 ′. The spring 44 urges the piston 42 ′ upwardly and away from the support plate 26 ′ with annular shoulder stop 104 defining the upper extent of movement of the piston 42 ′ in contacting the casing 36 . A cylindrical wall 106 extends upwardly from the shoulder stop 104 and through the aperture 38 , and a central passageway 108 is defined within the wall 106 . A check valve seat 10 is defined at an end of the passageway 108 which communicates with an inlet passageway 112 . A check valve 114 is disposed in the passageway 108 so as to seat on the inlet check valve seat 110 and regulate flow through the inlet passageway 112 . A lower annular piston ring 116 is defined about the inlet passageway 112 . The piston ring 116 is formed to engage the seal ring 32 ′ upon sufficient downward movement of the piston 42 ′.
A nozzle actuator 58 ′ is rigidly fixed to the piston 42 ′ so as to move unitarily therewith. The nozzle actuator 58 ′ is generally the same as the nozzle actuator 58 . The nozzle actuator 58 ′ is mounted on the piston 42 ′ in any manner so as to move unitarily therewith. In addition, an elongated block 118 is preferably provided which extends from the nozzle actuator 58 ′ and into the passageway 108 . In this manner, a reduced-diameter channel 120 is formed through the block 118 which communicates with passageway 60 and having a much smaller cross-section than the passageway 108 .
In use, the nozzle actuator 58 ′ is caused to translate downwardly (as shown by the arrow A), causing commensurate movement of the piston 42 ′. With sufficient movement, the piston ring 116 engages the seal ring 32 ′ and causes the lower pump chamber 34 to be sealed from the upper pump chamber 40 . With further downward movement of the piston 42 ′, the seal ring 32 ′ is caused to deflect outwardly, maintaining the seal between the pump chambers 34 and 40 intact. Further downward movement of the piston 42 ′ causes volume reduction of the lower pump chamber 34 , and an increase in pressure therein. With a sufficient increase in pressure, the check valve 114 is caused to lift from the valve seat 110 and pressurized fluid is forced through the inlet passageway 112 , the channel 120 and the passageway 60 to act on the discharge piston 64 (FIG. 5 ). The fluid is discharged form the discharge chamber 62 , in the same manner as described with respect to the pump system 10 . When the piston ring 116 goes through, and beyond, the seal ring 32 ′ (FIG. 6 ), pressure decays, the discharge piston 64 returns to its closed state, and the check valve 114 returns to its seated position on the valve seat 110 . With release of the nozzle actuator 58 ′, the spring 44 urges the piston 42 ′, and the nozzle actuator 58 ′, upwardly to the rest state shown in FIG. 4 . As the piston 42 ′ separates from the seal ring 32 ′, fluid is drawn from the reservoir 16 .
The four critical dimensions in the pump system 100 are the outer diameter x of the piston 42 ′; the diameter y of the seal ring 32 ′; the length t of the diameter x; and, the length z of flat surface 83 ′ on the seal ring 32 ′. The “z” dimension can be a radius or a small flat (0.005 inches); as such, dimensional variation is practically zero making three dimensions control dosage.
With reference to FIG. 7, a possible external configuration of a pump system is shown, which may be either the pump system 10 or the pump system 100 . Although the discharge nozzle 68 is shown to be covered in both FIGS. 1 and 4; it is in fact exposed, as shown in FIG. 7 . It is critical that the nozzle 68 not be covered by the wall 12 at a location where fluid is to be discharged therefrom.
With reference to FIGS. 8-9, a third embodiment of a pump system is depicted therein in cross-section and generally designated with the reference numeral 200 . The pump system 200 has the same basic structure and operates in the same basic manner as the first embodiment described above. However, the pump system 200 is an “in-line” dispenser having an exit aperture extending along the longitudinal axis of the pump system, such as in the manner of a nasal spray. Like reference numerals refer to identical or similar components described above.
The pump system 200 includes the exit aperture 52 formed in the piston cap 46 as with the first embodiment. However, the exit aperture 52 acts as a dispensing aperture for this embodiment in contrast to the first embodiment. Thus, fluid dispensed from the pump system 200 is dispensed along the longitudinal axis of the pump system 200 (which is coincident with the longitudinal axis of the stem 42 as shown in FIG. 8 ). To provide for actuation of the pump system 200 , actuator 202 is provided having finger grips 204 formed to be depressed by the pointer and middle fingers of a user. The actuator 202 is rigidly mounted to the piston cap 46 about shoulder 206 . With downward movement of the actuator 202 , the pump system 200 works in the same manner as described above. For illustrative purposes, as shown in FIG. 9, with downward movement of the actuator 202 , the stem 42 engages the seal ring 32 to form a seal therewith resulting in eventual separation of the stem 42 from the cap 46 , with exposure of the exit aperture 52 for dispensing pressurized fluid from the upper pump chamber 40 . Further downward movement of the actuator 202 results in pressure decay after a dose has been administered and full passage of the enlarged portion 82 beyond the seal ring 32 results in subsequent recharging of the pump system 200 . A release of the actuator 202 allows for return of the valve stem 42 to its rest position as shown in FIG. 8 .
FIG. 10 shows a fourth embodiment of the subject invention which is a variation of the third embodiment. Pump system 300 is also an “in-line” pump system which utilizes valve stem 42 , as in the first and third embodiments described above. Here, however pressure piston 302 applied to the reservoir 16 is applied in a downward motion to urge fluid up through tube 304 , having a passage 306 formed therein, and into the lower pump chamber 34 . Also, a swirl plug 308 may be provided between the piston cap 46 and actuator 310 . Various swirl plug configurations are known in the prior art. As an exemplary embodiment, as shown in FIGS. 11A-11C, the spray plug 308 may include radiating channels 312 . When fluid goes through the channels 312 and into the center of the plug 308 , a swirling motion is imparted to the discharging fluid, causing the fluid to break up into a spray pattern through nozzle 314 . In all other respects, the pump system 300 is essentially the same as the third embodiment.
As is readily apparent, numerous modifications and changes may readily occur to those skilled in the art, and hence it is not desired to limit the invention to the exact construction operation as shown and described, and accordingly, all suitable modification equivalents may be resorted to falling within the scope of the invention as claimed. | Pump systems are provided which allow for highly-accurate dose control. The pump systems may be provided with a valve stem or a piston, either having a constant-diameter stroke portion interposed between reduced-diameter portions. At least one stationary sealing member immovably affixed to a pump body is also provided formed to sealingly engage the stroke portion of the valve stem or the piston. The sealing member is also formed to not engage the reduced-diameter portions. As such, the volume of the administered dose is controlled by the stroke length, which, in turn, is a function of the dimensioning of the constant-diameter stroke portion and the dimensioning of the sealing member. Advantageously, with the subject invention, a minimal number of tolerances can be implicated in controlling dosing volume. | 1 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made with Government support under Contract No. W911W6-08-2-0001 awarded by the US Army. The Government has certain rights in this invention.
TECHNICAL FIELD
The present invention generally relates to gas turbine engine assemblies, and more particularly relates to turbine assemblies with improved cooling characteristics.
BACKGROUND
A gas turbine engine may be used to power various types of vehicles and systems. A particular type of gas turbine engine that may be used to power aircraft is a turbofan gas turbine engine. A turbofan gas turbine engine conventionally includes, for example, five major sections: a fan section, a compressor section, a combustor section, a turbine section, and an exhaust section. The fan section is typically positioned at the inlet section of the engine and includes a fan that induces air from the surrounding environment into the engine and accelerates a fraction of this air toward the compressor section. The remaining fraction of air induced into the fan section is accelerated into and through a bypass plenum and out the exhaust section.
The compressor section raises the pressure of the air it receives from the fan section, and the resulting compressed air then enters the combustor section, where a ring of fuel nozzles injects a steady stream of fuel into a combustion chamber formed between inner and outer liners. The fuel and air mixture is ignited to form combustion gases, which drive rotors in the turbine section for power extraction. The gases then exit the engine at the exhaust section.
In a typical configuration, the turbine section includes rows of stator vanes and rotor blades disposed in an alternating sequence along the axial length of a generally annular hot gas flow path. The rotor blades are mounted at the periphery of one or more rotor disks that are coupled in turn to a main engine shaft.
In most gas turbine engine applications, it is desirable to regulate the operating temperature of certain engine components in order to prevent overheating and potential mechanical failures attributable thereto. As such, most turbine components, particularly the stator vane and rotor blade assemblies may benefit from temperature management in view of the high temperature environment of the mainstream hot gas flow path. Accordingly, in many turbine sections, the volumetric space disposed radially inwardly or internally from the hot gas flow path includes an internal cavity through which a cooling air flow is provided. The cooling of the internal engine cavity attempts to maintain the temperatures of the rotor disks and other internal engine components that are suitable for their material and stress level.
However, in many conventional engines, relatively high levels of cooling air flows have been used to obtain satisfactory temperature control of the components within the internal engine cavity. In addition, the demand for cooling flow may be impacted by an irregular and unpredictable ingestion of mainstream hot gases from the hot gas flow path into the internal engine cavity. Various attempts to prevent hot gas ingestion between adjacent stator vanes and rotor blades have primarily involved the use of overlapping lip-type structures in close running clearance, often referred to as flow discouragers, but these structures have not been as effective as desired. Moreover, it is generally desirable to employ mechanisms to minimize this cooling air since air from the compressor used for cooling is not available for combustion. Additionally, temperature control of the flow discouragers should also be considered. If the flow discouragers are exposed to undesirably high temperatures, they may deform, which may impact their primary functions.
Accordingly, it is desirable to provide an improved gas turbine engine assembly that maintains proper temperature control. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.
BRIEF SUMMARY
In accordance with an exemplary embodiment, a gas turbine engine assembly includes a housing including an annular duct wall that at least partially defines a mainstream hot gas flow path configured to receive mainstream hot gas flow; a stator assembly comprising a stator vane extending into the mainstream gas flow; and a turbine rotor assembly upstream of the stator assembly and defining a turbine cavity with the stator assembly. The turbine rotor assembly includes a rotor disk having a forward side and an aft side, a rotor platform positioned on a periphery of the rotor disk, the rotor platform defining an aft flow discourager, a rotor blade mounted on the rotor platform extending into the mainstream gas flow, and an aft seal plate mounted on the aft side of the rotor disk. The aft seal plate has a radius such that the aft seal plate protects the rotor platform from hot gas ingestion of the mainstream hot gas flow path into the turbine cavity.
In accordance with another exemplary embodiment, a turbine assembly is provided for a gas turbine engine assembly defining a mainstream hot gas flow path that receives mainstream hot gas flow. The assembly includes a rotor disk having a forward side, an aft side, and a circumferential periphery, a rotor platform positioned on the periphery of the rotor disk, the rotor platform defining an aft flow discourager, a rotor blade mounted on the rotor platform extending into the mainstream gas flow, and an aft seal plate mounted on the aft side of the rotor disk. The aft seal plate defines at least one cooling channel configured to deliver cooling flow to the aft flow discourager.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:
FIG. 1 is a partial cross-sectional view of a gas turbine engine in accordance with an exemplary embodiment;
FIG. 2 is a partial cross-sectional view of a turbine section of the gas turbine engine of FIG. 1 in accordance with an exemplary embodiment; and
FIG. 3 is an enlarged cross-sectional view of a portion of the turbine section of FIG. 2 .
DETAILED DESCRIPTION
The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.
Broadly, exemplary embodiments discussed herein include gas turbine engine assemblies that maintain suitable temperatures and reduce or eliminate of the effects of hot gas ingestion. More particularly, exemplary gas turbine engine assemblies include a turbine rotor assembly with an aft flow discourager. An aft seal plate may be configured to cooperate with the aft flow discourager to protect the rotor disk components, including the aft flow discourager, from elevated temperatures and conditions. Additionally, the aft seal plate may have channels that deliver impingement cooling flow to the aft flow discourager.
FIG. 1 is a cross-sectional view of a gas turbine engine 100 , according to an exemplary embodiment. In general, exemplary embodiments discussed herein may be applicable to any type of engines, including turboshaft engines. The gas turbine engine 100 can form part of, for example, an auxiliary power unit for an aircraft or a propulsion system for an aircraft. The gas turbine engine 100 has an overall construction and operation that is generally understood by persons skilled in the art. The gas turbine engine 100 may be disposed in an engine case 110 and may include a fan section 120 , a compressor section 130 , a combustion section 140 , a turbine section 150 , and an exhaust section 160 . The fan section 120 may include a fan, which draws in and accelerates air. A fraction of the accelerated air exhausted from the fan section 120 is directed through a bypass section 170 to provide a forward thrust. The remaining fraction of air exhausted from the fan is directed into the compressor section 130 .
The compressor section 130 may include a series of compressors that raise the pressure of the air directed into it from the fan. The compressors may direct the compressed air into the combustion section 140 . In the combustion section 140 , the high pressure air is mixed with fuel and combusted. The combusted air is then directed into the turbine section 150 .
As described in further detail below, the turbine section 150 may include a series of rotor and stator assemblies disposed in axial flow series. The combusted air from the combustion section 140 expands through the rotor and stator assemblies and causes the rotor assemblies to rotate a main engine shaft for energy extraction. The air is then exhausted through a propulsion nozzle disposed in the exhaust section 160 to provide additional forward thrust.
FIG. 2 is a partial cross-sectional view of a turbine assembly such as the turbine section 150 of the gas turbine engine 100 of FIG. 1 in accordance with an exemplary embodiment. In general terms, the turbine section 150 includes a mainstream flow path 210 defined in part by an annular duct wall 212 for receiving mainstream hot gas flow 214 from the combustion section 140 ( FIG. 1 ).
The turbine section 150 includes an alternating sequence of stator assemblies 220 , 230 and rotor assemblies 240 . In the view of FIG. 3 , first and second stator assemblies 220 , 230 and one rotor assembly 240 are shown. The first and second stator assemblies will be referred to as “forward” and “aft” stator assemblies based on their relative orientation with respect to the illustrated rotor assembly 240 . In general, any number of stator and rotor assemblies 220 , 230 , 240 may be provided. As discussed in greater detail below, the mainstream hot gas flow 214 flows past the stator and rotor assemblies 220 , 230 , 240 .
The forward stator assembly 220 is formed by stator vanes 224 extending radially outward from a platform 226 to the wall 212 , and the aft stator assembly 230 is similarly formed by stator vanes 234 extending radially outward from a platform 236 to the wall 212 . The platforms 226 , 236 can be directly mounted to the combustor (not shown), or coupled to the combustor through intervening components, to form a portion of the mainstream flow path 210 with the wall 212 .
The rotor assembly 240 is formed by turbine rotor blades 242 projecting radially outwardly from a circumferential rotor platform 244 mounted on the periphery of a rotor disk 246 , which in turn circumscribes a main engine shaft (not shown). During operation, the mainstream hot gas flow 214 drives the rotor blades 242 and the associated rotor assembly 240 for power extraction, while the stator assemblies 220 are generally stationary.
Turbine rotor cavities 250 , 270 are formed between the stator assemblies 220 , 230 and the rotor assembly 240 . In the depicted embodiment, the disk cavities 250 , 270 will be referred to as a forward rotor cavity 250 and an aft rotor cavity 270 based on the position of the rotor assembly 240 . A forward gap 252 is formed between the mainstream flow path 210 and the forward rotor cavity 250 , and an aft gap 272 is formed between the mainstream flow path 210 and the aft rotor cavity 270 . As discussed in further detail below, a portion of the mainstream hot gas flow 214 may attempt to flow through the gaps 252 , 272 during operation. If unaddressed, the elevated temperatures of the mainstream hot gas flow 214 may adversely affect certain components in the rotor cavities 250 , 270 .
Various mechanisms of the turbine section 150 attempt to prevent, reduce, or mitigate the effects of the mainstream gas ingestion. For example, in the depicted exemplary embodiment, the forward gap 252 is defined by a stationary flow discourager 228 extending downstream from the platform 226 of the stator assembly 220 and a forward rotor flow discourager 254 extending upstream from the turbine platform 244 . Generally, the stationary flow discourager 228 and the forward rotor flow discourager 254 overlap one another such that the mainstream hot gas flow 214 flows over the discouragers 228 , 254 and stays in the mainstream flow path 210 instead of flowing through the forward gap 252 into the forward rotor cavity 250 . Similarly, the forward gap 272 is defined by an aft rotor flow discourager 248 extending downstream from the platform 244 of the rotor assembly 240 and a forward stationary flow discourager 238 extending upstream from the stator platform 236 . Generally, the aft rotor flow discourager 248 and the stationary flow discourager 238 overlap one another such that the mainstream hot gas flow 214 flows over the flow discouragers 248 , 238 and stays in the mainstream flow path 210 instead of flowing through the aft gap 272 into the aft rotor cavity 270 .
The rotor assembly 240 further includes a forward seal plate 256 that is generally concentric with the rotor disk 246 and is mounted on and rotates with a forward face of the rotor disk 246 . The forward seal plate 256 generally has a radius such that a peripheral portion 258 extends adjacent to the forward rotor flow discourager 254 . The forward seal plate 256 may form a forward seal plate cavity 260 with the forward face of the rotor disk 246 . The forward seal plate 256 cooperates with the stationary flow discourager 228 and forward rotor flow discourager 254 to prevent or inhibit hot gas ingestion. As discussed in greater detail below, the forward seal plate 256 also directs cooling air into the rotor disk 246 .
The rotor assembly 240 further includes an aft seal plate 276 that is generally concentric with the rotor disk 246 and is mounted on and rotates with an aft face of the rotor disk 246 . The aft seal plate 276 generally has a radius such that a peripheral portion 278 extends adjacent to the aft rotor flow discourager 248 . The aft seal plate 276 may form an aft seal plate cavity 280 with the aft face of the rotor disk 246 . As discussed in greater detail below, the aft seal plate 276 cooperates with the aft rotor flow discourager 248 and stationary flow discourager 238 to prevent, inhibit, or mitigate the effects of hot gas ingestion.
Additional temperature control mechanisms include cooling air 290 that flows through the rotor cavities 250 , 270 and through the rotor assembly 240 . In particular, the cooling air 290 may be obtained as bleed flow from a compressor or compressor section 130 ( FIG. 1 ) and flows to the forward seal plate cavity 260 to assist in maintaining an appropriate temperature of the rotor disk 246 and forward seal plate 256 . The cooling air 290 may additionally flow through a disk channel 262 in the rotor disk 246 . A seal 296 may be provided between the forward seal plate 256 and the rotor disk 246 to minimize leakage between the aft seal plate cavity 280 and the disk channel 262 . The disk channel 262 may be in fluid communication with internal passageways (not shown) through the rotor platform 244 and within the rotor blade 242 . As such, during operation, the cooling air 290 is drawn through the rotor disk 246 and rotor blade 242 for cooling these components. In one embodiment, the cooling air 290 may form a cooling film on the surface of the rotor blade 242 .
The cooling air 290 may additionally flow from the disk channel 262 to the aft seal plate cavity 280 to assist in maintaining an appropriate temperature of the rotor disk 246 and aft seal plate 276 . As discussed in further detail below with reference to FIG. 3 , the aft seal plate 276 defines a number of impingement cooling channels 292 that extend in a radial direction from the aft seal plate cavity 280 . In general, a number of impingement cooling channels 292 may be arranged circumferentially around the aft seal plate 276 . The impingement cooling channels 292 deliver the cooling air 290 to the underside of the platform 244 , particularly the aft rotor flow discourager 248 . A seal 294 may be provided to prevent leakage of the cooling air 290 and encourage flow into the impingement cooling channels 292 . In further embodiments, the impingement cooling channels 292 may receive cooling air 290 directly from the disk channel 262 or an alternate source.
FIG. 3 is an enlarged cross-sectional view of a portion 300 of the turbine section 150 of FIG. 2 . In particular, FIG. 3 illustrates the aft rotor flow discourager 248 , the peripheral portion of the aft seal plate 276 , and the impingement cooling channels 292 .
As noted above, ingested gas from the mainstream hot gas flow 214 may attempt to flow through the aft gap 272 into the aft rotor cavity 270 or through the forward gap 252 and the rotor assembly 240 to the underside of the aft flow discourager 248 . The aft seal plate 276 generally has an extended radius such that the peripheral portion 278 extends adjacent to the aft rotor flow discourager 248 . The aft seal plate 276 generally prevents, inhibits, or mitigates the effects of hot gas ingestion in this area by limiting the exposure of the rotor disk 246 , such as a majority or substantially all of the rotor disk 246 . The extended aft seal plate 276 may also limit hot gas flowing through the forward gap 252 to the underside of the aft flow discourager 248 . In general, the aft seal plate 276 is tucked under the aft flow discourager 248 as close as possible with consideration for manufacturing tolerances and relative radial deflections. For example, the aft seal plate 276 may have a radius that is at least 50% of the radius of the rotor disk 242 . In other exemplary embodiments, the aft seal plate 276 may have a radius that is at least 90%, 95%, or 100% of the radius of the rotor disk 242 . In one exemplary embodiment, the impingement gap (i.e., the gap between the aft seal plate 276 and the aft flow discourager 248 ) may be any suitable distance corresponding to the radius ratios discussed above. In other embodiments, the impingement gap may be a function of the diameter of the cooling channels 292 . For example, the ratio of the impingement gap and the diameter of the cooling channel 292 may be about 2:1. In other embodiments, the ratio may be any suitable ratio, including about 1:1 to about 1:3. In conventional turbine assemblies, the aft seal plate does not extend to adjacent the turbine flow discourager.
As also noted above, the impingement cooling channels 292 deliver cooling air 290 that directly impinges upon and cools the aft rotor flow discourager 248 . In conventional turbine assemblies, temperature control of the aft flow discourager is typically unaddressed, and as such, the aft flow discourager tends deform, particularly in a radially outward direction, which widens the gap and adversely affects the function of the flow discouragers. In general, the impingement cooling channels 292 are oriented such that the cooling air 290 strikes the aft rotor flow discourager 248 at an angle of approximately 90°, although other angles may be possible based on structural design and cooling requirements. In generally, the aft rotor flow discourager 248 is maintained at a temperature and stress combination such that little or no deformation of the discourager may occur. In general, the impingement cooling channels 292 may have a length/diameter ratio of approximately 2:1, although other ratios are possible such that satisfactory jets of cooling air 290 are established. In the depicted exemplary embodiment, the impingement cooling channel 292 extends past the seal 296 and cooling air is supplied from radially inward (i.e., below) the seal 296 . In further exemplary embodiments, the cooling channel 292 does not extend past the seal 296 and cooling air is supplied via controlled leakage past the seal 292 . The cooling air 290 from the impingement cooling channels 292 may also function as an ingestion inhibiting dynamic jet that assists in recirculating any ingested gas back into the mainstream flow path 210 . In some embodiments, the impingement cooling channels 292 may enable the aft flow discourager 248 to be extended and/or the stationary flow discourager 238 to be shortened relative to conventional assemblies. In other embodiments, the lengths of the aft flow discourager 248 and the stationary flow discourager 238 are not modified.
Computational fluid dynamics (CFD) analysis may be used to determine the number, orientation, dimension, and position of the impingement cooling channels 292 . In general, design of impingement cooling channels 292 may depend on factors including application and engine design. In one exemplary embodiment, the impingement cooling channels 292 are provided to maintain the aft flow discourager 248 to a suitable temperature. Considerations may include engine application, required heat extraction, stress analysis, the temperature and pressure of the cooling air, and convective cooling effectiveness. The impingement cooling channels 292 may be formed, for example, by EDM or STEM drilling.
The aft seal plate 276 may additionally include one or more axial flanges 282 , 284 that provide additional support to the aft seal plate 276 during operation. Particularly, axial flanges 282 , 284 are configured such that undesirable deflections do not occur as the aft seal plate 276 rotates. For example, axial flange 282 may prevent the seal 294 from separating from the aft face of the rotor disk. Similarly, axial flange 284 maintains the position of the impingement cooling channels 292 relative to the aft rotor flow discourager 248 , which may be important if the peripheral portion 278 has a reduced amount of material resulting from the formation of the impingement cooling channels 292 .
Accordingly, exemplary embodiments provide a turbine section 150 with improved temperature control characteristics. In general, in combination or individually, the extended radius aft seal plate 276 and the impingement cooling channels 292 may mitigate and/or protect the aft flow discourager 248 from hot gas ingestion as well as high temperatures of the mainstream gas flow. Exemplary embodiments may particularly prevent or reduce creep of the aft flow discourager 248 while not adding additional material to the rotor disk 246 , turbine platform 244 , and/or the aft flow discourager 248 . Exemplary embodiments may also maintain the aft flow discourager 248 under centrifugal load. Exemplary embodiments may minimize the amount of air necessary to cool the gas turbine engine 100 and increase efficiency. Additionally, because of the simplicity of the design, the systems and methods disclosed herein can be readily incorporated on new design engines or it can be economically retrofitted on existing engines. The gas turbine engine assemblies produced according to exemplary embodiments may find beneficial use in many industries including aerospace, but also including industrial applications such as electricity generation, naval propulsion, pumping sets for gas and oil transmission, aircraft propulsion, automobile engines, and/or stationary power plants.
While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims. | A gas turbine engine assembly includes a housing including an annular duct wall that at least partially defines a mainstream hot gas flow path; a stator assembly with a stator vane extending into the mainstream gas flow; and a turbine rotor assembly upstream of the stator assembly and defining a turbine cavity with the stator assembly. The turbine rotor assembly includes a rotor disk having a forward side and an aft side, a rotor platform positioned on a periphery of the rotor disk, the rotor platform defining an aft flow discourager, a rotor blade mounted on the rotor platform extending into the mainstream gas flow, and an aft seal plate mounted on the aft side of the rotor disk. The aft seal plate has a radius such that the aft seal plate protects the rotor disk from hot gas ingestion. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of pending U.S. patent application Ser. No. 11/122,775, filed May 5, 2005, U.S. Pat. No. 7,575,874, Aug. 18, 2009, which is a continuation of PCT International Patent Application No. PCT/NL2003/000776, filed on Nov. 6, 2003, designating the United States of America, and published, in English, as PCT International Publication No. WO 2004/042398 A1 on May 21, 2004, and claims priority to European Patent Application No. 02079666.0 filed Nov. 7, 2002, the contents of the entirety of each of which are hereby incorporated herein by this reference.
TECHNICAL FIELD
[0002] This invention relates to the detection of, among other things, tumor-specific fusion proteins. More specifically, the invention relates to techniques that indicate the presence of chromosomal translocations by detecting the presence of a fusion protein at the single cell level. In the diagnosis of various types of cancer, such as leukemias, lymphomas and solid tumors, chromosome aberrations are frequently used for classification into prognostically relevant subgroups. 1 Many of these chromosome aberrations result in fusion genes, i.e., aberrantly coupled genes coupled via the upstream part of one gene to the downstream part of the other gene, or vice versa. Fusion genes can be transcribed into fusion gene transcripts and translated into fusion proteins. Generally, fusion proteins play an important role in the oncogenetic process. So far, more than a hundred different fusion genes and fusion proteins have been described in various types of cancer. 2-5
BACKGROUND
[0003] The term “cancer” comprises a heterogeneous group of neoplasms, in which each type has its own characteristics when considering its malignant potential and its response to therapy. It goes without saying that accurate diagnosis and classification of the various cancer types is pre-eminent in helping to select the most effective therapy. Furthermore, a diagnostic method allowing the detection of small numbers of malignant cells in a high background of normal cells during therapy is essential for evaluating treatment effectiveness and for anticipating an impending relapse.
[0004] Chromosomal translocations can be detected by a wide array of techniques, most of which entail modern biomolecular technology. Cytogenetic techniques include conventional chromosomal banding techniques (karyotyping) and fluorescence in situ hybridization (FISH) which uses fluorescently labeled probes. Polymerase chain reaction-(PCR-) based strategies can be used to detect fusions of chromosomal breakpoints as can be found in chromosomal translocations, inversions and deletions using primers located at each side of the breakpoint. DNA amplification can only be used for chromosome aberrations in which breakpoints cluster in a small area. In most cases, breakpoints spread over large intronic regions, but several translocations, inversions and deletions give rise to fusion genes and fusion transcripts suitable for PCR amplification after a reverse transcription step (RT-PCR).
[0005] Most commonly used techniques aimed at detecting specific chromosomal aberrations involve analysis at the chromosomal or nucleic acid (DNA or RNA) level. An advantage of such genetic fusion markers is their direct involvement in oncogenesis. Accordingly, their presence is constant all over disease evolution. However, a major drawback of fusion markers relates to the fact that variations in the level of gene transcription and/or gene translation during the disease and particularly during therapy cannot be excluded. Thus, variations in expression of a fusion gene transcript or a fusion protein make it difficult to correlate the level of detection of the marker to the amount of malignant cells. This implies that detection of a fusion gene product is preferably performed at the protein level in individual cells.
[0006] A fusion protein comprises parts of at least two proteins that correspond to, and were originally transcribed by and translated from, the originally separated genes. Fusion proteins are uniquely characterized by a fusion point where the two proteins meet. Fusion points are often antigenically exposed, comprising distinct epitopes that sometimes can be immunologically detected.
[0007] Initially, attempts were made to raise fusion protein-specific antibodies by generating antibodies against a peptide corresponding to the joining region of a fusion protein. This approach has rarely been successful, mainly because of the fact that it is difficult to find immunological reagents that are exclusively reactive with a fusion protein and not with the non-fusion proteins that are normally produced in a cell. If fusion-specific antibodies were obtained, they were generally not applicable to fluorescence microscopy or flow cytometry. 6-8 For example, the ERP-FP1 antibody against the BCR-ABL fusion protein works well in Western blotting procedures but is not successful in microscopic studies on human BCR-ABL-positive leukemias. 6, 7 Moreover, considering the large variation within individual rearrangements seen in chromosomal translocations and depending on the localization of the breakpoint within the non-aberrant gene (even when the translocations occur within the same two genes) wherein different fusion proteins can be generated, it is deemed likely that within each separate case of fusion proteins, new fusion points arise. Detection of fusion proteins by specific immunologic detection of the fusion-point epitope of the fusion protein has, therefore, never been widely applicable.
[0008] An alternative method for the specific detection of fusion proteins involves the application of a so-called catching antibody that recognizes one part of a fusion protein and a labeled detection antibody that recognizes another part of a fusion protein. In such a system, a catching antibody is bound to a solid support layer, such as an ELISA plate or a dipstick. A catching antibody may also be immobilized onto beads that can be analyzed by flow cytometry. 9 Following incubation of a catching antibody with a cellular lysate suspected of containing the fusion protein, bound fusion protein is detected by a labeled detection antibody. Although elegant and easy to perform, a catching/detection antibody system cannot be applied practically to detect an intracellular fusion protein without disrupting the cell integrity. Most tumor-specific fusion proteins are localized intracellularly, e.g., nuclear transcription factors, or signaling molecules that reside in the cytoplasm or that shuttle between the cytoplasm and the nucleus. Thus, a catching/detection antibody system does not allow detection of an intracellular fusion protein at the single cell level.
[0009] Co-localization of two differentially labeled antibodies against two different parts of a fusion protein could, in theory, prove the presence of a fusion protein in a single cell. However, to full proof co-localization requires analysis by confocal laser scanning microscopy (CLSM). Even then, it is generally not straightforward to evaluate co-localization of two antibodies because the recognized normal proteins that are derived from the normal genes on the unaffected chromosomes can cause a background staining that interferes with the detection of the fusion protein. Further, CLSM has the great disadvantage that it requires a specialized and well-equipped laboratory and trained and highly skilled personnel. Such a time-consuming and highly specialized technique is not desirable for routine diagnostic procedures, e.g., in a clinical setting.
[0010] All of the above indicate that there is a specific need for an improved method to detect a fusion protein, which can preferably be used in a clinical laboratory. Particularly challenging is the detection of an intracellular fusion protein at the single cell level.
SUMMARY OF THE INVENTION
[0011] Provided is the insight that fluorescence resonance energy transfer (FRET) technology can be used to detect the presence of a fusion protein. Provided are methods for detecting the presence of a fusion protein in a cell using a set of at least a first and a second molecular probe, each probe capable of recognizing a binding site positioned at opposite sides of the fusion region of the fusion protein, each probe provided with a dye wherein the dyes together allow energy transfer, comprising providing a set of probes, providing a sample comprising a cell, contacting the sample with the probes under conditions that allow juxtaposing the probes on the fusion protein, removing any unbound and any non-specifically bound probe and detecting juxtaposition of the probes via FRET to determine the presence of the fusion protein.
[0012] Also provided is a set of at least a first and a second molecular probe, each probe provided with a dye wherein the dyes together allow energy transfer; at least one probe provided with a reactive group allowing juxtaposing at least the first and second probes, wherein the reactive group allows modulation of juxtaposing the probes, such that there is an increased likelihood of energy transfer between the dyes. According to the invention, a molecular probe is capable of specifically binding to a biological molecule of interest via its so-called binding domain. Following binding of at least a first and a second probe to a molecule of interest via the binding domain, a reactive group can be used to modulate juxtapositioning. A reactive group has no or a minimal tendency to compete with the binding domain for binding to a molecule of interest. Herewith, a set of probes of the invention is distinguished from known sets of antibody probes that are clustered or juxtaposed by the mere binding to one antigenic molecule or complex. A reactive group preferably remains available for modulating the spatial organization of juxtaposed probes after the probe is bound to a molecule of interest. In one embodiment, the molecule of interest is a protein, preferably a fusion protein, more preferably an oncogenic fusion protein. Particularly preferred is a set of a first and a second molecular probe wherein each probe is capable of recognizing and binding to a binding site (epitope) positioned at opposite sides of the fusion region of the fusion protein. Of course, when using a set of probes wherein each probe binds to a different epitope of a molecule of interest (e.g., epitopes at the C- and N-terminal side of the fusion region of a fusion protein), the different epitopes should not interact with each other in either an inter- or intramolecular fashion because this would interfere with probe binding. Different probes within a set of probes are, therefore, capable of binding to different, essentially non-interacting epitopes. This is unlike the situation described in WO 01/75453 relating to methods for detecting an entity by virtue of two probes (reporters), wherein the two probes may bind to the same target site on the entity, either substantially simultaneously or sequentially, or to different target sites. The reporters/probes of WO 01/75453 may be used for detecting a chimeric fusion protein. It is mentioned that one reporter preferably binds an SH2 domain and the other reporter binds to an SH2-binding site, i.e., the probes of WO 01/75453 preferably bind to interacting epitopes. Such probes and detection methods are distinct from the invention because a FRET-based method as provided herein would simply not work when using a set of probes wherein different probes are directed against either identical or interacting epitopes. Moreover, none of the probes of WO 01/75453 is provided with a reactive group allowing juxtaposing the probes.
[0013] Also provided is a diagnostic kit comprising a set of probes according to the invention and a method using a set of probes for detecting the presence of a fusion protein in the diagnosis and/or classification of a disease as well as before, during and after treatment of a disease to evaluate the effectiveness of the treatment.
[0014] Also provided is a method for producing a probe set according to the invention comprising contacting each probe with a dye to form a conjugate between the probe and the dye and purifying the conjugate, further comprising contacting at least one probe with a reactive group or a derivative thereof to form a conjugate between the probe and the reactive group and purifying the conjugate.
[0015] Fluorescence resonance energy transfer (FRET) is a distance-dependent interaction between the electronic excited states of two dye molecules in which a “donor” molecule, after excitation by a light source, transfers its energy to an “acceptor” molecule. In general, the donor and acceptor dyes are different, in which case, FRET can be detected by the appearance of sensitized fluorescence of the acceptor or by quenching of donor fluorescence. When the donor and acceptor dyes are the same, FRET can be detected by the resulting fluorescence depolarization. Energy transfer occurs when the emission spectrum of the acceptor overlap significantly. To achieve resonance energy transfer, the donor must absorb light and transfer it through the resonance of excited electrons to the acceptor. 10-13 FRET is usually based on the interaction between donor and acceptor dyes that are both fluorescent. However, non-fluorescent acceptor dyes can also be used. Nonfluorescent acceptor dyes can be advantageous because they eliminate the background fluorescence that results from direct (i.e., nonsensitized) acceptor excitation. In the invention, it is possible to monitor juxtaposed probes on a fusion protein using a fluorescent donor dye and a nonfluorescent acceptor dye. Specific binding of a set of probes to the native proteins, e.g. proteins A and B, will give a basal fluorescence signal. Upon close juxtapositioning of a set of probes on an A-B fusion protein, FRET between the probes will quench the donor fluorescence. Rather than measuring an increase in acceptor fluorescence, use of a nonfluorescent acceptor involves measuring a decrease in donor fluorescence. Generally speaking, detection of a decreased signal is less sensitive compared to detection of an increased signal. Therefore, a method according to the invention is preferably practiced using a fluorescent donor and a fluorescent acceptor dye.
[0016] For energy transfer to take place, the fluorescence emission wavelength of the donor must be lower than the excitation wavelength of the acceptor; that is, the process must be energetically “downhill.” Sufficiently close juxtaposition of the two dyes, generally closer than 100 Ångstrom but preferably closer than 50 Ångstrom, is essential for energy transfer between the donor/acceptor pair. One Ångstrom, a metric unit of length, is equal to 0.1 nanometer or 10 −10 meter. The FRET energy transfer efficiency is inversely proportional to the sixth power of the distance between the donor and the acceptor. The insight is provided that, due to this high sensitivity to distance, FRET is especially suitable in detecting the juxtaposing of two different dye-conjugated probes on a fusion protein.
[0017] In a preferred embodiment, a probe set comprises a set of at least two dye-conjugated antibodies, each antibody capable of recognizing a binding site positioned at opposite sides of the fusion region of a fusion protein. A suitable antibody comprises a conventional (poly- or monoclonal) or a synthetic antibody or a binding fragment functionally equivalent thereto, such as a Fab′, Fab, a single chain Fv fragment, a diabody (a single chain Fv dimer) and the like. For example, a chimeric fusion protein A-B can be detected via FRET using a set of dye-conjugated probes, e.g., an anti-A antibody and an anti-B antibody. In a preferred embodiment, a sample is contacted with two antibodies, one against domain A and the other against domain B of a fusion protein to detect the presence of an A-B fusion protein in a cell sample. One antibody is labeled with a FRET donor dye and another with a FRET acceptor dye. Only when domain A is in close proximity to domain B, e.g., when both are part of the same protein molecule, the two antibodies become sufficiently close together (“juxtaposed”), which allows the donor/acceptor pair to induce a detectable FRET fluorescence signal.
[0018] Simultaneous reactivity of more than one different antibody with the same protein molecule needs recognition of two different binding sites or epitopes that are sufficiently separated in order to prevent steric hindering of the antibodies. For example, simultaneous application of an antibody against the variable (V) domains and an antibody against the constant (C) domains of T-cell receptor (TCR) molecules on the cell surface of a T-lymphocyte gives no reliable and reproducible results. However, simultaneous application of V domain antibodies and an antibody against the CD3 molecule, which is closely associated with the TCR molecule, yielded excellent staining results in both flow cytometry and microscopy. 14 These data suggest that the distance between two epitopes on the same protein should preferably be more than approximately 80 Ångstrom to be recognized simultaneously.
[0019] Co-localization of two dye-conjugated antibodies against different parts of the same fusion protein is sometimes not sufficient for the required FRET energy transfer. A complete antibody is a large Y-shaped protein molecule, ˜150 kDa in size, made up of two heavy chains and two light chains. Owing to the length of an antibody molecule (300 to 400 Ångstrom) and the flexibility of the hinge region, juxtaposed antibody molecules can bridge a relatively large distance. 15 Because closely juxtaposed FRET probes are in general sufficient for obtaining a FRET signal, it may be advantageous to stabilize and/or enhance juxtaposing two probes in order to increase FRET efficiency. For example, the size of a probe or a dye might interfere with FRET analysis via negative steric effects. Also, the flexibility of an antibody may decrease the probability of FRET occurrence between a pair of FRET dyes that are conjugated to antibody probes. When preparing a dye conjugate, like a fluorescent probe, it is in general not possible to control the site of conjugation. For example, in case of antibody conjugation, a dye moiety might become attached to different parts of the antibody molecule. Depending on the site of dye-conjugation, the spatial orientation of dyes on probes can be favorable or unfavorable for FRET energy transfer efficiency, i.e., dyes attached to probes need not necessarily be within energy transfer distance of each other.
[0020] Surprisingly, the invention provides the insight that juxtaposing a set of probes can be modulated in order to increase the probability of FRET energy transfer between a pair of dyes, by providing at least one probe with a reactive group. The invention provides a set of at least a first and a second molecular probe, each probe provided with a dye wherein the dyes together allow energy transfer; at least one probe comprising a reactive group allowing juxtaposing at least first and second probes, wherein the reactive group allows modulation of juxtaposing the probes such that there is an increased likelihood of energy transfer between the dyes. Use of such a probe set allows detection of juxtaposed probes with an improved sensitivity compared to use of probes not comprising any reactive groups.
[0021] In the present context, the term “reactive group” refers to a moiety that allows modulating the spatial organization of FRET dyes such that there is an increase in the probability of energy transfer to occur and/or an increase in energy transfer efficiency. The spatial organization refers to both the distance between the dyes as well as to their relative orientation. Modulating the spatial organization includes adjusting and stabilizing the spatial organization of dyes. One of the primary conditions for energy transfer to occur is that donor and acceptor molecules must be in close proximity, typically 10-100 Å. In a preferred embodiment, a reactive group allows juxtaposing the dyes within a distance of 100 Å of each other, more preferably within 50 Å of each other but most preferably within a distance of 20 Å of each other. It is, therefore, preferred that a reactive group is small, e.g., smaller than 10 kiloDalton (kD), more preferred, smaller than 5 kDa, even more preferred, smaller than 2 kDa or most preferred, smaller than 1 kDa. For example, a reactive group is biotin.
[0022] As said, a reactive group allows modulating juxtaposed probes such that there is an increased likelihood of energy transfer between dyes by directly interacting with another probe. For example, a reactive group of a first probe binds to a part of a juxtaposed second probe to form a stable complex between the probes in a spatial orientation that is favorable for FRET to occur. As mentioned above with respect to the site of dye conjugation, it is often not possible to selectively modify a probe with a reactive group at a defined site. The site of modification is mainly determined by the presence and accessibility of a certain residue via which a reactive group is conjugated to a probe, e.g., via primary amines or via thiol groups. Thus, an antibody probe may contain a reactive group at either the constant and/or the variable region of the immunoglobulin. It is conceivable that not every site is equally suitable for interacting with a second probe, e.g., due to steric hindrance. Therefore, it is preferred that a probe is provided with a multiplicity of reactive groups to statistically increase its capacity to interact with another probe. For example, a probe is provided with two or three or even five reactive groups.
[0023] Provided herein is a method for detecting the presence of a fusion protein in a cell using a set of at least a first and a second molecular probe, each probe capable of recognizing a binding site (via its binding domain) positioned at opposite sides of the fusion region of the fusion protein, each probe further provided with a dye wherein the dyes together allow energy transfer, at least one probe provided with a reactive group allowing modulation of juxtaposing at least the first and second probes such that there is an increased likelihood of energy transfer between the dyes, comprising providing a set of probes, providing a sample comprising a cell, contacting the sample with the probes under conditions that allow juxtaposing the probes on the fusion protein, removing any unbound and any non-specifically bound probe and detecting juxtaposition of the probes via FRET to determine the presence of the fusion protein. In the case where a first probe can interact directly with at least a second probe, it is preferred to contact the sample with each probe in consecutive steps with extensive intermittent washing procedures to avoid self-association between probes. For example, a sample is contacted with probe A, comprising a reactive group, to allow recognition of and binding to one part of a fusion protein. Next, any unbound and any non-specifically bound probe A is removed by repeated washing steps. Subsequently, the sample is contacted with probe B reactive with another part of the fusion protein under conditions allowing juxtaposing probe A and B on the same fusion protein. Also here, any unbound and any non-specifically bound probe B is preferably removed by repeated washing steps. In one embodiment of the invention, a reactive group of probe A interacts with at least a juxtaposed probe B to enhance and/or stabilize the spatial orientation of the dyes present on the probes such that there is an increased likelihood of energy transfer between them. Although this method can be used to detect the presence of a fusion protein, such a procedure, involving multiple separate contacting and washing steps, can be rather laborious and time-consuming. Moreover, if probes are capable of directly interacting with each other, a significant background staining can be expected caused by probes binding to the domains on the normal proteins that are derived from the normal genes instead of the fusion gene. In the example above, a reactive group of probe A which is bound to the native protein A might recruit and interact with probe B. Also, if not all unbound probe A is efficiently removed, an unwanted interaction between probe A and B can occur upon contacting the sample with probe B. Both events may result in a detectable energy transfer signal, despite the fact that probe B is not juxtaposed to probe A on a fusion protein.
[0024] Thus, in a preferred embodiment of the invention, a reactive group of a first probe is not directly or immediately reactive with a second probe in order to avoid self-association of the probes. This is advantageous for an optimal recognition of a fusion protein by each probe and for juxtaposing the probes on the fusion protein. Moreover, it avoids untimely energy transfer to occur between directly connected or multimerized probes and decreases an a specific background signal. This is important to ensure that an energy transfer signal truly reflects juxtaposed probes.
[0025] The invention provides the insight that, if a reactive group of a first probe is not reactive with at least a second probe in order to avoid self-association of the probes, a so-called “bridging” substance may be used to mediate an interaction between the probes, allowing modulation of juxtaposing the probes such that there is an increased likelihood of energy transfer between the dyes on the probes. A substance may be any kind of compound capable of binding to or modifying a probe, a reactive group and/or a dye to modulate the spatial organization of dyes on juxtaposed probes such that it is favorable for FRET. Preferably, a substance allows juxtaposing the dyes within a distance of 2 to 100 Ångstrom of each other. The substance is preferably added to a sample following binding of dye-conjugated probes to a target fusion protein, in an amount effective to modulate the spatial organization of the dyes on juxtaposed probes. Advantageously, the substance binds to a reactive group with a high specificity and a high affinity. Also, it is preferred that such a substance is relatively small so that the bridging substance only minimally affects the distance between a pair of dyes and the relative orientation of a pair of dyes.
[0026] In a preferred embodiment, a method is provided for detecting the presence of a fusion protein in a cell using a set of at least a first and a second molecular probe, each probe capable of recognizing a binding site positioned at opposite sides of the fusion region of the fusion protein, each probe further provided with a dye wherein the dyes together allow energy transfer, at least one probe provided with a reactive group allowing modulation of juxtaposing at least a first and second probe such that there is an increased likelihood of energy transfer between the dyes, wherein a reactive group of the first probe is not directly reactive with the second probe, comprising providing a set of probes providing a sample comprising a cell, contacting the sample with the probes, under conditions that allow juxtaposing the probes on the fusion protein, removing any unbound and any non-specifically bound probe, contacting the probes with a substance capable of linking at least a reactive group of the first probe to the second probe and detecting juxtaposition of the probes via FRET to determine the presence of the fusion protein.
[0027] A method using a probe set of at least one probe comprising a reactive group wherein probes do not directly interact and requiring a bridging substance has several advantages. First, an improved specificity and reduced background staining can be achieved compared to a method using probes that can directly interact. After all, for a reactive group to exert its effect via a bridging substance, probes need to be in a close juxtaposition of each other prior to the addition of the substance, i.e., resulting from binding of one probe adjacent to another probe on the same fusion protein. Second, the procedure is fast and easy because no separate contacting/washing steps are required for each individual probe. Thus, it permits contact of a sample with a mixture of probes all together in a single action. Likewise, any unbound and any non-specifically bound probes can be removed simultaneously.
[0028] Much preferred, as exemplified herein in the detailed description, is a set of at least a first and a second molecular probe, each probe provided with a dye, wherein the dyes together allow energy transfer; each probe provided with a reactive group. A substance is preferably capable of binding or “bridging” at least two reactive groups. In a preferred embodiment, each probe within a set of probes is provided with the same reactive group. Also, each probe within a set of probes may be provided with a different reactive group but having the same reactivity. This allows the use of one type of bridging substance having at least two identical binding sites for a reactive group.
[0029] In a preferred embodiment, a probe is provided with more than one reactive group, enabling the probe to interact with more than one molecule of bridging substance. Providing a probe with more than one reactive group will theoretically increase the likelihood of an interaction between the probe and a bridging substance. Furthermore, for the ease of practicing the invention, a suitable reactive group or a derivative thereof is commercially available and can be easily and efficiently attached to a probe.
[0030] In accordance with the invention, a particularly interesting reactive group is biotin, with avidin or streptavidin being a particularly suitable bridging substance. Avidin is an egg white-derived glycoprotein with a molecular weight of about 68,000 daltons and a diameter of 8 to 10 Ångstrom. It consists of four identical subunit chains. One avidin or streptavidin molecule can bind four molecules of biotin. Avidin has an extraordinarily high affinity (affinity constant>10 15 M-1) for biotin. This high affinity assures the user of a rapidly formed and stable complex between avidin and the biotin-labeled probes. The protein streptavidin, produced by the bacterium Streptomyces avidinii , has a structure very similar to avidin, and also binds biotin tightly. It often exhibits lower non-specific binding, and thus is frequently used in place of avidin. Once a biotin-avidin complex forms, the bond is essentially irreversible. The biotin-avidin system is widely used and has proven to be very useful in the detection and localization of antigens, glycoconjugates, and nucleic acids by employing biotinylated antibodies, lectins, or nucleic acid probes. As said, a reactive group with such a small size is advantageous for achieving a close distance between a dye pair. Biotin is a vitamin with a molecular weight of only 244 daltons. Also, many biotin molecules can be coupled to a protein, enabling the biotinylated protein to bind more than one molecule of avidin. Avidin, streptavidin and biotin are available from many commercial sources. Various standard procedures for preparing biotin conjugates are known to those skilled in the art, most of which can be completed within a day. Moreover, commercial biotinylation kits are available that contain all the necessary components for protein biotinylation.
[0031] If a set of probes is used wherein each probe is provided with a different reactive group, a suitable substance comprises a molecule capable of binding at least one of each reactive group. Alternatively, such a binding substance comprises a complex of at least two molecules that can be covalently or non-covalently attached to each other, wherein each molecule is capable of binding to a reactive group.
[0032] The invention provides a method for detecting a fusion protein at the single cell level using a set of probes according to the invention, each probe capable of binding to a binding site positioned at opposite sides of a fusion region of the fusion protein via the binding domain of the probe, i.e., one probe is directed against a protein fragment comprising the N-terminal fragment of a fusion protein, and another probe is directed against a protein fragment comprising the C-terminal fragment of the same fusion protein. A fusion protein comprises any kind of proteinaceous substance that is formed after transcription and translation of a fusion gene. A fusion gene comprises one part of one or more genes combined with another gene or a part derived thereof. A fusion protein may be the result of a chromosomal translocation, inversion or deletion. In a preferred embodiment, a method provided is used to detect a tumor-specific fusion protein. A fusion protein may be an endogenously expressed protein or it may be the result of genetic engineering. Fusion proteins in malignancies that can readily be detected using a method according to the invention include, but are not limited to, those listed in Table I.
[0033] It is of great relevance to note that the present method does not require disruption of the cell integrity, e.g., the preparation of a cell lysate, to detect the presence of an intracellular fusion protein. Preservation of the morphology integrity of a cell permits analysis at the single cell level, for example, by flow cytometry or fluorescence microscopy. Detection of a FRET signal by flow cytometry offers the ability to perform rapid, multiparametric analysis of specific individual cells in a heterogeneous population. The main advantage of flow cytometry is that it directly gives quantitative data and that it is very rapid (results can be obtained in a few hours).
[0034] The method provided in the invention allows detection of a fusion protein at the single cell level. In a preferred embodiment, the method provided is used to detect an intracellular protein at the single cell level. When detecting an intracellular fusion protein, a sample comprising a cell is treated so as to obtain a permeabilization of the material and a preservation of the morphology. The preferred treatment is one that fixes and preserves the morphological integrity of the cellular matrix and of the proteins within the cell as well as enables the most efficient degree of probe, e.g., antibody penetration.
[0035] Unlike, for example, a “catching/detection” antibody method, which can essentially only be applied to detect the presence of a fusion protein at the cell surface or in a cell lysate, the present method allows gating of the subset of cells that are present in a mixture of cells via immunophenotypic characteristics. Consequently, the method provided herein permits the detection of a fusion protein in a rare population of malignant cells in a large background of normal cells. This is especially advantageous for detecting low frequencies of fusion-positive cells, like in the case of detection of minimal residual disease (MRD) during or after treatment for evaluation of treatment effectiveness. In a preferred embodiment, the method provided includes multiparameter flow cytometry to identify and/or isolate single cells to detect the presence of a fusion protein at the single cell level. All that is required for practicing the method provided is a flow cytometry facility. Importantly, the procedure can be performed in routine laboratories by personnel with ordinary skills.
[0036] More than a hundred different fusion genes and fusion proteins have been described in various types of cancer. As said, the method provided allows discrimination between the presence of normal proteins and an aberrant fusion protein at the single cell level. Theoretically, two antibodies recognizing two different domains of a fusion protein can cause a background staining by binding to the domains on the normal proteins that are derived from the normal genes instead of the fusion gene. However, generally only one of the two normal proteins reaches a detectable expression level in a target cell population, as defined by cell surface and/or intracellular markers. Furthermore, the normal proteins and the fusion protein often differ in their intracellular expression pattern, frequently resulting in a different subcellular localization. 16, 17 This implies that coincidental co-localization of the two different normal proteins is unlikely to occur at a significant level in the target cell population. In particular, coincidental juxtaposing probes sufficient for a FRET signal will be rare in normal cells, if this occurs at all.
[0037] Provided herein is a method for producing a set of at least a first and a second molecular probe, each probe provided with a dye wherein the dyes together allow energy transfer; at least one probe provided with a reactive group allowing juxtaposing the first and second probes, comprising contacting each probe with a dye to form a conjugate between the probe and the dye and purifying the conjugate, further comprising contacting at least one probe with a reactive group or a derivative thereof to form a conjugate between the probe and the reactive group and purifying the conjugate. The Förster radius (R 0 ) is the distance corresponding to 50% energy transfer efficiency and it characterizes each donor/acceptor pair. Its value is generally between 30 and 60 Ångstrom. In the present context, the term “dye” refers to a substituent that, in concert with another dye, can be used for energy transfer analysis, such as FRET analysis. As mentioned above, FRET is usually based on the interaction between donor and acceptor dyes that are both fluorescent. In one embodiment, the invention uses a set of probes wherein at least one of the dyes is a fluorochrome. However, a nonfluorescent acceptor may also be used and FRET is detected by quenching of donor fluorescence. As said, detecting FRET by monitoring a decrease in donor fluorescence as a consequence of juxtapositioned probes is often not as sensitive as detecting an increase in acceptor fluorescence. Thus, in a preferred embodiment, at least two fluorescently labeled probes are used to detect a fusion protein, as is exemplified in the detailed description. Examples of preferred fluorochromes are those suitable for analysis by conventional flow cytometry and include fluorescein labels, e.g., 5-(and 6-) carboxyfluorescein, 5- or 6-carboxyfluorescein, 6-(fluorescein)- 5 - (and 6-) carboxamide hexanoic acid and fluorescein isothiocyanate, Alexa Fluor dyes such as Alexa Fluor 488 or Alexa Fluor 594, cyanine dyes such as Cy2, Cy3, Cy5, Cy7, optionally substituted coumarin, R-phycoerythrin, allophycoerythrin, Texas Red and Princeton Red as well as conjugates of R-phycoerythrin and, e.g., Cy5 or Texas Red and members of the phycobiliproteins. Other dyes of interest are quantum dot dyes, which come in a nearly unlimited palette of colors. Extensive information on donor/acceptor pairs suitable for energy transfer detection by flow cytometry can be found in Szollosi et al. 18 Preferred combinations of fluorochromes comprise those dyes used in the classical tandem conjugates, also referred to as duochromes. 19
[0038] The method provided comprises providing a sample comprising a cell, whereby the sample is optionally subject to fixation and permeabilization if an intracellular fusion protein is to be detected. A sample may comprise a primary cell that is obtained from a biological sample. A biological sample can be a body fluid sample including blood, serum, urine, bone marrow, cerebrospinal fluid (CSF), or saliva. It may also be a tissue sample or tissue homogenate. A sample comprises a cultured cell that may be a cultured primary cell, for example, tumor cells obtained from a lymph node biopsy. Furthermore, a sample may comprise a cultured cell from an established laboratory cell line, like a K562, KASUMI-1, REH or CEM cell line, which can be obtained from a number of sources such as the American Type Culture Collection. The method provided is suitable for detection of the presence of an endogenous fusion protein, as well as a recombinant fusion protein, in a cell.
[0039] For analyzing a sample comprising a suspension of cells, it is preferred that the sample is treated so as to obtain a preservation of the morphology of the material and permeabilization in order to ensure sufficient accessibility of a molecule of interest to a probe. The type of treatment will depend on several factors, for instance, on the fixative used, the extent of fixation and the type and properties of the molecule of interest. Fixation may be carried out with a fixative such as formaldehyde.
[0040] For the detection of a fusion protein in primary cells, it is especially advantageous to use an additional marker to define a target cell population of interest. A number of important biological applications in infectious diseases, MRD detection and monitoring, and gene therapy typically require the analysis and isolation of rare cells (e.g., hemopoietic stem/progenitor cells) from a large background. In one embodiment of the invention, the method includes staining a sample for at least one cellular marker, like a cell surface marker or an intracellular marker, to define a target cell population within a mixture of cells comprising contacting the sample with a compound capable of selectively binding to the marker. In a preferred embodiment, such a compound is directly tagged with a fluorescent dye. A suitable compound comprises a fluorescently labeled antibody or a binding fragment functionally equivalent thereto. Also, a compound capable of selectively binding to a cellular marker can be used that can be detected using a dye-conjugated secondary reagent (e.g., a fluorescently labeled secondary antibody). A cellular marker comprises any kind of intracellular or membrane-bound marker that can be used to distinguish a subpopulation of cells in a mixture of cells. A mixture of cells comprises living cells. It also comprises permeabilized and/or fixed cells. A cellular marker can be a cluster of differentiation (CD) antigen. CD markers are cell surface molecules of, among others, hemopoietic cells that are distinguishable with monoclonal antibodies. Hemopoietic cells comprise thymocytes, dendritic cells, Langerhans' cells, neutrophils, eosinophils, germinal centre B cells, follicular dendritic cells, plasma cells and bone-marrow cells. For example, suitable cellular markers comprise CD1, CD3, CD4, CD8, CD10, CD19, CD20, CD33, CD34 and CD117. Monoclonal antibodies directed against a large number of human CD markers can be obtained from various suppliers, such as BD Biosciences or Ancell Immunology Research Products, Bayport, USA. Often, antibodies are available that are directly conjugated with a fluorochrome of choice, e.g., CD10-PE or CD19-FITC, which is a preferred choice to practice a method according to the invention.
[0041] In a preferred embodiment, a method is provided to identify and/or isolate rare single cells using multiparameter flow cytometry/cell sorting techniques and to further characterize these cells by the presence or absence of a fusion protein of interest. Such a method is particularly suited for application to a number of important problems in immune system development, infectious diseases, cancer and gene therapy. Typically, prior to staining a cell sample with a probe set, cells are labeled with at least one relevant dye-conjugated antibody according to standard procedures in order to define a target cell population. The choice of dye should preferably, but not exclusively, aim at the usage of two or three dyes for immunophenotyping in addition to the FRET dyes for detection of a fusion protein. For example, a FRET probe set according to the invention can be combined with another dye to mediate leukocyte subset gating via immunophenotypic characteristics, e.g. CD10, CD19 and CD20 to accurately define subsets of precursor-B-cells in bone marrow, or CD1, CD4 and CD8 to define subsets of thymocytes, or CD84 and/or CD117 to identify stem/precursor cell populations. As shown herein in the detailed description, the invention provides a method that allows the detection of an intracellular fusion protein in a very small subset of cells, i.e. detection of MRD, which is essential for evaluating effectiveness of cancer treatment.
[0042] The invention provides a diagnostic test kit for detecting the presence of a fusion protein in a cell, comprising a set of probes according to the invention. For example, such a kit may be used for monitoring and quantification of malignant cells, e.g. leukemic cells, via the detection of tumor-specific fusion protein-positive cells. The diagnostic test kit provided herein is useful at the time of diagnosis as well as during and after treatment to evaluate the effectiveness of the applied cancer treatment protocol.
[0000]
TABLE I
Examples of fusion proteins in malignancies that can
be detected via antibody-mediated FRET technology.
Malignancy
Chromosome aberration
Fusion protein
Precursor-B-ALL
t(1; 19) (q23; p13)
E2A-PBX1
t(4; 11) (q21; q23)
MLL-AF4
t(9; 22)(q34; q11)
BCR-ABL
t(12; 21)(p13; q22)
TEL-AML1
Acute myeloid
t(8; 21) (q22; q22)
AML1-ETO
leukemia
t(15; 17)(q22; q21)
PML-RARA
inv(16)(p13; q22)
CBFB-MYH11
Lymphoma
t(2; 5)(p23; q35)
NPM-ALK
Ewing sarcoma
t(11; 22)(q24; q12)
EWS-FLI1
DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1 . Schematic diagram of a fusion gene consisting of the upstream (5′) part of gene A and the downstream (3′) part of gene B. This A-B fusion gene is transcribed into A-B mRNA and translated into an A-B fusion protein.
[0044] FIG. 2 . Schematic diagram of the principle of fluorescence resonance energy transfer (FRET) with fluorochrome X as donor dye and Y as acceptor dye. A. The acceptor dye Y will not be excited by the emission light of the donor dye X, if the distance between X and Y is too large. B. If the distance between the donor and acceptor dye is sufficiently small (<80 Ångstrom but preferably <50 Ångstrom), the emission light of the donor dye X will excitate the acceptor dye Y.
[0045] FIG. 3 . Schematic diagram of the A-B fusion protein recognized by a set of anti-A and anti-B antibody probes. A. Probe A is conjugated with donor dye X and probe B is conjugated with acceptor dye Y (see, FIG. 2 ). Furthermore, both probes are conjugated with biotin as a reactive group. B. After incubation with antibody probes A and B, the probes can be bound together via incubation with avidin, provided that the two probes indeed recognize and bind to the same A-B fusion protein. This juxtaposition of the two antibodies (stabilized by the biotin-avidin system) is detectable via the FRET principle (see, FIG. 2 ).
[0046] FIG. 4 . Example of FRET-mediated detection of the TEL-AML1 fusion protein in ALL cells. A. Precursor B-ALL cells at diagnosis. Flow cytometric gating on ALL blast cells as defined by light scatter characteristics (left), followed by gating on CD19+ blast cells (middle), and evaluation of the presence of the TEL-AML1 fusion protein within the CD10 + /CD19 + ALL cells (right). B. Precursor B-ALL cells during follow-up. Flow cytometric detection of low frequencies of TEL-AML1-positive cells (minimal residual disease) during follow-up for evaluation of treatment effectiveness. Only 3% of the CD10+ blasts were positive for TEL-AML1 fusion protein, i.e. only 0.2% of total leukocytes.
DETAILED DESCRIPTION OF THE INVENTION
[0047] As mentioned above, the invention relates to a method for determining the presence of a fusion protein in a cell using a probe set. This method can be used to diagnose various types of cancer that involve chromosomal translocations, inversions or deletions that give rise to a fusion gene. For example, approximately 35% of adult patients with acute lymphoblastic leukemia (ALL) and chronic myeloid leukemia (CML) are associated with a specific chromosomal defect, a translocation between chromosomes 9 and 22 that creates the Philadelphia (Ph) chromosome. This translocation occurs at the site in the genome of a protein tyrosine kinase named ABL, creating the abnormal BCR-ABL fusion protein, a gene product of the in-frame fusion of the ABL gene with another gene called BCR. Generally, fusion proteins play an important role in the oncogenetic process. For example, the kinase activity of ABK in the BCR-ABL fusion protein is activated and deregulated, driving the uncontrolled cell growth observed in ALL and in CML. When acute lymphoblastic leukemia is diagnosed in a patient, typically comprising traditional cytogenetics such as karyotype analysis for the Ph chromosome, the total number of leukemia cells is approximated to 10 11 to 10 13 . A majority of patients reach complete remission after about 5 weeks of chemotherapy. Complete remission does not mean that the leukemic cells are totally eradicated from the body but that their level is beyond the sensitivity level of classical cytomorphologic methods (e.g. 1 to 5%). At this time, up to 10 10 malignant cells can still remain in the patient. They represent the minimal residual disease (MRD). Detection of low frequencies of residual malignant cells allows a longer follow-up of the tumor burden during chemotherapy and thus, permits better appreciation of the sensitivity of leukemia cells to treatment. It is now established that the level of MRD represents a powerful prognostic factor for final outcome. Besides, the detection of an increase of the MRD level enables anticipation of impending relapse. The method provided in the invention allows discrimination between the presence of normal proteins and an aberrant fusion protein at the single cell level.
[0048] As an example of this method, described is the preparation of a probe set for the detection of the TEL-AML1 fusion protein. Also described is a method using this probe set to detect the presence of TEL-AML1 fusion protein in ALL cells at the time of diagnosis and during follow-up to detect the level of MRD.
Example
Preparation of a Set of Probes
[0049] Preferably, a probe set according to the invention comprises a set of two fluorochrome-conjugated antibodies, each antibody additionally provided with a reactive group. Methods of producing an antibody are known to those skilled in the art. For example, to obtain a polyclonal antibody, a laboratory animal is immunized with an immunogen such as a recombinant protein or a synthetic peptide. The animal's immune response is monitored by taking test bleeds and determining the titer of the reactivity. When appropriately high titers are obtained, blood is collected from the animal and antisera are prepared.
[0050] Further fractionation of the antisera to enrich for antibodies reactive to the protein can be done if desired. See, e.g., Harlow et al. Antibodies. A Laboratory Manual , Cold Spring Harbor Publications, New York (1988). Monoclonal antibodies can be obtained by various techniques known in the art, for example, by fusing spleen cells of immunized mice with a myeloma cell line by the addition of polyethylene glycol (PEG). Fused cells are cultured in a selection medium, e.g., medium containing a mixture of hypoxanthine, aminopterin and thymidine. Fused cells that survive in this selection medium are tested for the production of the desired antibody (often by solid-phase immunoassay such as ELISA) and, if positive, the cultures are cloned so that there is only one cell in each culture well. This produces a clone of cells from a single progenitor that is both immortal and a producer of monoclonal antibody. Antibodies obtained can be characterized using conventional immunodiagnostic techniques, e.g., by Western blotting using lysates of cells expressing a recombinant fusion protein or by ELISA.
Biotinylation of Antibodies
[0051] Biotin is typically conjugated to proteins via primary amines (i.e., lysines). Usually, between three and six biotin molecules are conjugated to each antibody. Dialyze or exchange over a column the antibody in 100 mM carbonate, pH 8.4. Measure the antibody concentration after buffer equilibration. (For IgG, 1 mg/ml has an A 280 of 1.4.) If the antibody concentration is less than 1 mg/ml, the conjugation will probably be sub-optimal. If necessary, dilute the antibody to a concentration of 4 mg/ml. Dissolve 10 mgs of biotin (N-hydroxysuccinimidobiotin, Pierce) in 1 ml anhydrous DMSO (anhydrous dimethyl sulfoxide, Aldrich) immediately before use. The reactive biotin molecule is unstable. Once the biotin is solubilized, it should be used immediately. Add biotin to give a ratio of 80 μg per mg of antibody; mix immediately. Wrap the tube in foil; incubate and rotate at room temperature for two hours. Remove the unreacted biotin and exchange the antibody into 10 mM Tris pH 8.2, 150 mM NaCl, pHix (5 mg/ml pentachlorophenol in 95% ethanol (use as 10,000×, or 3-4 drops per liter) Sigma).
FITC Conjugation of an Antibody
[0052] FITC is a small organic molecule, and is typically conjugated to proteins via primary amines (e.g., lysines) of an immunoglobulin. Usually, between three and six FITC molecules are conjugated to each antibody; higher conjugations can result in solubility problems as well as internal quenching (and reduced brightness). Thus, an antibody will usually be conjugated in several parallel reactions to different amounts of FITC, and the resulting reagents will be compared for brightness (and background stickiness) to choose the optimal conjugation ratio. The entire conjugation can be performed in about a half-day. The reactive fluorescein molecule, fluorescein isothiocyanate, is unstable. Once a vial has been cracked and the FITC solubilized, it should be used immediately. Since single vials of FITC contain sufficient material for ˜100 mgs of antibody, it is economical to perform multiple FITC conjugations on the same day.
1. Antibody Preparation
[0053] Dialyze or exchange over a column the antibody in 500 mM carbonate, pH 9.5. Measure the antibody concentration after buffer equilibration. (For IgG, 1 mg/ml has an A 280 of 1.4.) If the antibody concentration is less than 1 mg/ml, the conjugation will probably be sub-optimal. If necessary, dilute the antibody to a concentration of 4 mg/ml.
2. Covalent Conjugation
[0054] Dissolve 10 mgs (the entire contents of one vial; no need to weigh) of FITC (Molecular Probes) in anhydrous DMSO immediately before use. Add FITC to give a ratio of 40-80 μg per mg of antibody; mix immediately. Wrap the tube in foil; incubate and rotate at room temperature for one hour. Remove the unreacted FITC and exchange the antibody into 500 mM carbonate, pH 9.5 by gel filtration or dialysis.
3. Characterization of the Conjugate
[0055] Determine F/P and protein concentration by measuring the absorbance at 280 and 495 nm. IgG: 1 mg/ml has an A(280) of 1.4; mw=150,000. IgM: 1 mg/ml has an A(280) of 1.2; mw=900,000. Fluorescein: 1 mM has an A(495) of 68 and an A(280) of 11.8. F/P values of 3-10 are probably optimal for any particular IgG.
[0056] Protein Concentration:
[0000] IgG (mg/ml)=[ A (280)−0.31.* A (495)]/1.4
[0000] IgM (mg/ml)=[ A (280)−0.31* A (495)]/1.2
[0057] F/P Ratio:
[0000] IgG: 3.1*A(495)/[A(280)−0.31*A(495)]
[0000] IgM: 15.9*A(495)/[A(280)−0.31*A(495)]
Detection by FRET Analysis
[0058] A bone marrow sample is obtained from an ALL patient and leukocytes are isolated according to standard procedures. Leukocytes are labeled with two cell surface markers to define a leukocyte subset via immunophenotypic characteristics. FITC-conjugated monoclonal anti-human CD19 (FITC-CD19) and PE-conjugated monoclonal anti-human CD10 (PE-CD10) were used. Cells are then fixed according to standard procedures, e.g. in 1% paraformaldehyde, to preserve the integrity of the cell and its content. The cell membrane is permeabilized using a detergent such as saponin to make the cell interior accessible to probe set. Cells are labeled for one hour at 4° C. in the dark with a mixture containing a probe set according to the invention (0.1 to 0.3 microgram/ml of each probe), comprising a Cy3-labeled biotin-conjugated antibody against the helix-loop-helix motif of TEL and a Cy5-labeled biotin-conjugated antibody against the Runt domain of AML1. After washing of the cells to remove unbound probe, the cells are incubated with unlabeled avidin to induce sufficiently close and stable juxtaposing of the two different antibodies. The cells are then analyzed in a flow cytometer. Results are shown in FIG. 4 . Panel A shows the evaluation of the TEL-AML1 fusion protein in precursor-B-ALL cells obtained from a patient at the time of diagnosis. ALL blast cells are first gated on the basis of their light scatter characteristics (forward scatter versus side scatter). Then, CD19-positive blast cells are gated (FL1 versus side scatter). The presence of the TEL-AML1 fusion protein is readily detectable in the subset of CD19+/CD10+ALL cells. In panel B, similar analyses are shown from the same patient after a five week therapy protocol to evaluate the effectiveness of the treatment. Only 3% of the CD10+ blast cells are positive for the TEL-AML1 fusion protein, i.e., only 0.2% of total leukocytes. The detection of such a low frequency of TEL-AML1-positive cells (minimal residual disease) has not been shown before.
[0059] The FacsCalibur® was used to perform FRET measurements using Cy3 and Cy5 as donor/acceptor pair. The 488 nm excitation is not optimal for Cy3 (543 would be better), 632 is optimal for Cy5, and with this setup, reasonably good FRET distribution curves were obtained (actually better than that obtained with FITC/TRITC pair because auto-fluorescence is much less of a problem). In addition, the 488->520 band was used for auto-fluorescence correction on a cell-by-cell basis. Data acquisition and analysis were performed using Cell Quest Pro software.
REFERENCES
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3. Rabbitts T. H., Chromosomal translocations in human cancer. Nature 1994; 372:143-9.
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8. Sang B. C., L. Shi, P. Dias, et al., Monoclonal antibodies specific to the acute lymphoblastic leukemia t(1;19)-associated E2A/PBX1 chimeric protein: characterization and diagnostic utility. Blood 1997; 89:2909-14.
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14. Van den Beemd R., P. P. Boor, E. G. van Lochem, W. C. Hop, A. W. Langerak, I. L. M. Wolvers-Tettero, H. Hooijkaas, and J. J. M. van Dongen. Flow cytometric analysis of the Vbeta repertoire in healthy controls. Cytometry 2000; 40:336-345.
15. I. Roitt. Essential Immunology . Oxford: Blackwell Scientific Publications; 2001; 37-58.
16. Falini B., L. Flenghi, M. Fagioli, et al., Immunocytochemical diagnosis of acute promyelocytic leukemia (M3) with the monoclonal antibody PG-M3 (anti-PML). Blood 1997; 90:4046-53.
17. Falini B., and D. Y. Mason, Proteins encoded by genes involved in chromosomal alterations in lymphoma and leukemia: clinical value of their detection by immunocytochemistry. Blood 2002; 99:409-26.
18. Szollosi J., S. Damjanovich, and L. Matyus, Application of fluorescence resonance energy transfer in the clinical laboratory: Routine and research. Cytometry 1998; 34:159-179.
19. Tanke H. J. Fluorochromen voor twee- en drievoudige labelingen. Immunofenotypering in de diagnostiek: indicatiestellingen, uitvoering en interpretatie. Eds. Van Dongen, Groeneveld, Adriaansen, Hooijkaas (ISBN 90-73436-16-8). 1994; pages 55-61. | The invention relates to the detection of fusion proteins. Described are a set of at least a first and a second molecular probe, each probe provided with a dye wherein the dyes together allow energy transfer, at least one probe provided with a reactive group allowing juxtaposing at least the first and second probes wherein the reactive group allows modulation of juxtaposing the probes such that there is an increased likelihood of energy transfer between the dyes. A method is provided which permits detecting the presence of a fusion protein in a cell at the single cell level. | 6 |
This application is a division of application Ser. No. 516,714, filed 7/25/83, now U.S. Pat. No. 4,606,008.
BACKGROUND OF THE INVENTION
In commercial, industrial and domestic applications it is often useful to determine quickly the position, speed or direction of rotation of a movable body such as a meter hand, a robot arm, or perhaps an abnormality in a plate of dielectric material. For an example of the former, various means have been developed for determining the position of the dial hands of utility meters so as to permit them to be read rapidly and automatically from a remote location. In contrast with conventional practice in which a utility company employee periodically visits each meter to obtain a visual reading, remote meter reading offers very significant economic benefits. By suitable means, for example, all the meters in a large apartment complex can be read in a few seconds from a single location outside the building or in the basement; or meters can be read several times daily to allow the utility to obtain energy flow data, study consumption patterns, or (by the use of time-of-day rates) discourage consumption during periods of high demand.
Clearly, in such a reading means a highly desirable feature is the ability to read ordinary utility meters which are already in service. Nonetheless, with the exception of previous work by and on behalf of the assignee of this application, remote meter dial reading has been generally possible only through the use of expensive specially-equipped meters which replaced the ordinary meter already in use. The above-mentioned previous efforts by and on the part of the assignee have resulted in meter-reading systems disclosed in U.S. Pat. Nos. 3,500,365, 4,433,332 and 4,007,454; and in U.S. patent application Ser. No. 375,919, filed May 7, 1982 and now abandoned. In each of these patents and applications, in general, a sensing transducer scans the dials of the meter by inducing an electric or magnetic field which includes the hands. The theory of the aforementioned patents and applications is that the transducer's field can be coupled to the meter hand through the intervening space, and variations in the phase of the resultant signal detected give an indication of the meter hand's position. Because no mechanical parts that move relative to one another are used, potential problems of maintenance and reliability are eliminated.
Improvements to the devices disclosed in the above-mentioned patents and applications are also disclosed in U.S. Pat. No. 4,429,308 assigned to the assignee of this application. This application is directed to a peculiar shape of the field-producing electrode which provides improved uniformity of angular sensitivity. Also, a further improvement is disclosed in U.S. Pat. No. 4,214,152, issued July 22, 1980, which involves a technique for compensation for the mechanical misalignment of one of a plurality of meter hands by adjusting the reading of a more significant hand responsive to the hand position of the adjacent lesser significant integer.
SUMMARY OF THE PRESENT INVENTION
The present invention is also directed to a method and apparatus for detecting the presence and/or position of objects causing a disturbance to the field of such a phase-sensitive transducer, wherein the transducer is a prescribed circular array of electrodes (or in the magnetic approach, a circular array of pole pieces). While the present invention may be adapted to other applications such as the determination of the position of the arm of a robot or the location of openings or flaws in a planar workpiece, for the most part the invention will be described herein as being utilized for the determination of the position of a meter hand, keeping in mind that the techniques of the invention are equally applicable to other areas.
In contrast with conventional phase-measuring techniques, typically concerned with directly-measured timing relationships between sinusoidal signal waveforms, one aspect of the present invention permits a more accurate determination of phase and hence of hand angle, from the measured amplitude ratios of a plurality of periodic, stepwise signal levels. Stepwise levels arise from the use of certain properties of square waves by a novel field-excitation approach utilized in this invention. By these means it has been found possible to simplify manufacture and eliminate errors which are often introduced by waveshape imperfections in earlier, sinusoidally-driven models of the transducer described above. Further, according to a second aspect of the invention there is provided an accurate calculation of the quality of the phase-related signal from the amplitude relationships between periodic, stepwise signal levels without the necessity for difficult measurements of complex, continuously-varying waveshapes. Moreover, and in accordance with a third aspect, the present invention allows rapid compensation for the effect of varying distance between the transducer and the hand, increasing the span of distances over which the transducer can be satisfactorily operated, reducing its cost, and simplifying its installation on the meter. Further, the present invention employes a novel technique for converting the numerical results of the transducer's reading process into standard ASCII code: this aspect of the invention accomplishes the desired conversion faster and with less computational hardware than is otherwise possible.
More particularly, in accordance with the first aspect of the present invention, the drive, array, and detector system to be herein described produce a resultant cyclic signal of six steps repeated over and over in time. The signal is periodic, and a complete cycle of six steps is equal to 360° of phase angle or 2π radians. The six steps occur at fixed times after the transition of the reference phase (i.e. at 0, π/3, 2π/3, π, 4π/3, and 5π/3 radians). The six-step levels are transferred through a digital logic controlled sample and hold gate so that they may be acquired by the system microprocessor with an analog to digital (A/D) converter with a variable gain prescaler. The signal is then analyzed for quality and, if acceptable, is used to calculate the hand angle.
In general the signal is produced by generating a plurality of phase modulated drive signal pairs, each pair consisting of a signal and its complement. Each of the drive signals is a plurality of two-phase square waves of the same amplitude and frequency, and the transition of all drive levels occurs synchronously. For a prescribed period of a given number of cycles (N), each drive signal changes phase by 180° each N/2 cycles. Also in the same period of N cycles, where K equals the number of drive signals, each phase shift occurs N/K cycles subsequent to the phase shift of the previous drive. The period of N cycles is so selected such that 2N/K is an integer. Each of the aforementioned drive signals are fed to a separate electrode in the electrode array in such a manner that each signal and its complement are fed to diametrically opposed electrodes. The relationship of the phase progression of the drive signals is proportional to the angular relation of the electrodes. The drive signals are coupled (capacitively or permittively) to a central node through the meter hand in such a manner that the algebraic sum of each drive signal pair is constant in the absence of any variation (meter hand). In the presence of a variation (meter hand) the algebraic sum of each drive signal pair varies at the same frequency as the drive signals, so that the signal on the central node is the superposition of the algebraic sum of all drive signal pairs.
The resultant signal on the central node is sampled by generating a synchronous gating pulse at a time betwen transitions of the drive signals. The gating pulse is relatively short (of a duration less than one-half the duration of the drive signal period) and at the same frequency as the drive signal, so that the resultant synchronously detected signal is in the form of a multi-step signal in the which the number of steps is equal to the number of drives. The resulting synchronously detected signal is then a multi-step approximation to a sine wave in which the phase angle between the sine wave and a timing point (phase transistion of a given drive signal) is proportional to the angular position of the dielectric variation (meter hand) confronting the transducer.
According to the second aspect of the invention, the hand angle is then calculated utilizing the six step cyclic signal. First, the six steps are converted into terms representative of the imbalance of the drive signals, which terms are vectors spaced 120° apart (hereinafter referred to as vectors A, B, and C). While the six signals could be converted directly to two orthogonal vectors, it is preferred to first determine the three vectors of A, B, and C to facilitate tweaking of the system (obtaining a balanced or net resultant zero signal in the absence of a hand). The three phases are then combined as vectors into two orthogonal vectors, I and J. The algebraic (+ or -) signs of I and J are used to determine in which quadrant the phase of the signal lies (keep in mind there are four quadrants in 2π radians). The size of vector I versus vector J is then compared to determine whether the resultant vector is within π/4 (45°) of the I axis or not (whether J/I is greater or less than 1). The ratio of J and I is then the tangent of the resultant vector. The arctangent of J/I is determined through a successive approximation routine with proper adjustment for quadrant and proximity to the I axis.
The above technique for determining J/I is utilized to determine the phase angle of the hand position which is then converted to a binary representation thereof. According to yet another aspect of the invention the amplitude of the sine wave approximation is utilized later in the calculation process to make a compensation on the resulting hand angle value based on the distance of the transducer from the meter hand. When the meter hand at "zero position" is spaced some distance from the transducer, the calculated 0 may not actually coincide with the actual or physical 0. Therefore a predetermined compensation value is added to the signal representing the hand position, which value is a function of the distance between the hand and the electrode array. This distance is correlated to a change in signal amplitude. The amplitude based correction is made utilizing a lookup table.
In accordance with another aspect of the invention the revised or corrected signal is then further compensated to provide for mechanical misalignment of hands, which is referred to as an Inter-Dial Compensation (IDC). In meter reading devices of the type described hereinabove, a problem may arise because of mechanical inaccuracies in the meter. As will be well recognized, most meters which must be read constitute a plurality of dials (or hands) which represent, for example, kilowatt hours, tens of kilowatt hours, hundreds of kilowatt hours, and thousands of kilowatt hours. In some cases the hands are not accurately aligned with the numerals on the dial face. For example, when the reading of the kilowatt hand is at 2, having just passed 0, the tens of kilowatt dial should be 2/10 of the digital distance beyond one of the integers thereon, for example, 0.2. Due to misalignment, however, the tens of kilowatt dial may, for example, be pointing in a direction which would apparently be reading 9.9. If the dial readings are obtained independently, errors then can clearly be carried through the system.
To correct or compensate for the possible misalignment of certain hands or dials, the present invention introduces a technique whereby the least significant dial is read first and then a compensating offset value is generated for the next dial. For each reading of a dial after the first, there is automatically added a correction factor to the apparent value of the indicator being read which is based on a cumulative correction factor from the previously adjusted values of all lesser significant indicators. The compensation value is continuously adjusted responsive to the reading from the lesser significant dials, so that the adjusted reading from any selected more significant dial will tend to fall exactly halfway between two adjacent integers. The compensation adjustment continues from each less significant dial to the next more significant dial as a cumulative adjustment factor, so that when the reading is completed, errors due to mechanical misalignment should be eliminated.
As previously stated the phase angle of the hand position is converted to a binary representation thereof. In accordance with the present invention the conversion is effected by utilizing binary coded integers whose range is so selected as to facilitate calculations and compensations and to provide a resulting value that readily converts to the BCD of the integer value of the hand position. The key to this special range is that the circle is first broken into 640 parts. That means that each quadrant includes 160 parts and each half-quadrant has 80 parts. These are important considerations in determining the arctangent of the phase angles of the hand, which will be converted to a number between zero and 639.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a timing diagram of a pair of phase shifted drives;
FIG. 2 is a schematic representation of a simple conventional single-sided detector circuit which could be used with the present invention;
FIG. 3 is a schematic representation of a more reliable double-sided differential detector circuit used for synchronously detecting the output signal from the transducer plate;
FIG. 4 is a timing diagram representation of a single sine wave drive synchronously detected by a pair of sampling gates;
FIG. 5 is a timing diagram representative of a square wave drive signal as used in the present invention demodulated by a single gate resulting in a simple square wave;
FIG. 5a is a plan view of the electrode arrangement contemplated by the present invention;
FIG. 6 is a timing diagram representative of the relation of the drive signal pairs according to the present invention;
FIG. 6a is illustrative of the signal received from the central node and its subsequent synchronous detection;
FIG. 7 is a representation of the six step signal generated by synchronously sampling the signal from the central node in accordance with the present invention;
FIG. 8 is an electrical block diagram of the six step acquisition system;
FIG. 9 is a diagrammatic representation of the detected signal separated into its three components;
FIG. 10 is a graphic representation of a quadrant diagram showing the I and J vectors with 45° bisectors;
FIG. 11 is the arctangent lookup table;
FIGS. 11a and 11b together form an electrical schematic of the circuit for amplifying and synchronously demodulating the signal from the transducer plate central node;
FIG. 11c is the amplitude compensation lookup table;
FIG. 12 is a major block diagram of the system of the present invention;
FIG. 13 is a functional block diagram of the generation of the drive and sample signals;
FIG. 14 is a block diagram of the gates, carrier and system clock generator circuit;
FIG. 15 is a block diagram of the phase modulation signal generation portion of the system;
FIG. 16 is a block diagram of the phase modulator and transducer drive logic portion of the system;
FIG. 17 is a block diagram of the sample and hold logic for synchronously sampling the steps of the demodulated signal;
FIG. 18 is a program flow chart interfacing the sample and hold digital logic with the central processing unit;
FIG. 19 is a block diagram of the baud rate generator;
FIG. 20 is a block diagram of the 5-bit shift register which controls the dial-enable function;
FIG. 21 is a program flow chart of the interdial compensation technique; and
FIG. 22a thru 22q are program flow charts of the system of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is directed to a transducer system which utilizes a set (six) of phase-modulated electrical drives and a double-sided synchronous detection system to detect the position of an object having electrical characteristics which differ from the characteristics of the surrounding medium, as for example, the position of a meter hand. Phase, of course, is the temporal relationship of two periodic phenomena, such as electrical signals in the present invention. Phase is measured in terms of a portion of a complete cycle of one of the signals. Thus, one cycle equals 360° or 2π radians. In order to measure time differences or phase, some standard point or landmark must be used. Since the signals may be square waves, as well as sine waves, the peaks are not generally used as the landmark. Rather, a conventional technique which has developed for measuring phase relationship is to utilize the positive-going zero crossing point, with zero defined as a level midway between the high and low extremes (FIG. 1). This is referred to as the "zero crossing technique" and is well known. Another known technique for generating a phase landmark is the "phase locked loop" technique.
By way of background leading up to a discussion of the present invention a phase demodulation system will be outlined. Assume that A is a reference gating pulse, which synchronously gates or generates samples from another periodic signal S for some period, ΔT. The mean level then of the sampled signal is a function of the phase angle, θ, between the two signals, although not unambiguously so. A simple single-sided sample and hold circuit for performing this task is shown in FIG. 2.
Obviously, some information will be lost in that only a brief portion of the signal is sampled. A second synchronous gating pulse B can be generated 180° delayed from the gate pulse A. If a signal S is sampled again with pulse B, and the resultant signal is inverted and added to resultant signal generated by pulse A, then there results a "differential detection system" which achieves two ends: (a) the effective signal is doubled; and (b) shifts in the DC or low frequency level of the signal are cancelled out, producing a more reliable signal (E) with consequent rejection of a common DC or low level component (this is termed "common mode rejection"). The circuit for producing such a differential detection signal is outlined in FIG. 3. This circuit also amplifies the resulting signal.
Thus, where there is a signal S sampled by gating pulse GA, and the phase difference between the signals and the gating pulse GA changes smoothly, then the sampling window moves smoothly through the entire cycle of the signal, tracing out the signal at an expanded time scale (FIG. 4). This may be thought of as a beat frequency, f E , determined as: f E =(f GA -f S ). This holds true for both single- and double-sided sampling cases. If f GA and f S are known, then f E is also well known. If signals GA and S both commence with a certain phase relationship, they will return to that phase relationship after a calculable number of cycles according to the following equation: ##EQU1## A new "supra" time period is thus defined (FIG. 4), which is required for θ (the phase relationship between GA and S) to cycle 2π radians. Again, the signal E is related to the phase θ between signals S and GA. Therefore, if a reference signal R with a period of ##EQU2## exists, a new phase angle φ can be defined as the relative phase of S (relative to GA) and R (relative to E). Since θ is the phase of S with respect to GA, then φ is related to θ in such a manner that if θ is determined as the zero-crossing of R, then φ=θ (it should be kept in mind that φ is the phase angle of the phase of E at the zero-crossing of R).
A periodic signal, S A , can be generated (FIG. 1). A second signal, S B , is generated which has the same frequency as S A , but is phase shifted ρ with respect to it (see FIG. 1). If a signal is detected which may be either S A or S B , then it can be determined which signal it is by examining φ with respect to the reference signal. If φ=0, the signal is S A . On the other hand if φ=ρ, then the signal is S B . Mathematically if two sine waves are added together, a single sine wave results defined by the following equation:
C sin (ωt+Ψ)=A sin (ωt)+B sin (ωt+ρ).
The addition in the above equation is of a vectorial nature. The important consideration is that a single sine wave with a phase angle of Ψ results. The angle Ψ is a function of ρ and the ratio of A to B. If ρ is known (i.e. fixed), then ρ is a function of the ratio of A to B (vector addition). Therefore, if Ψ can be measured, then there results a measure of the ratio of A to B.
If one has a system which differentially couples S A and S B according to the position of some object (meter hand), then the position of the object can be determined from Ψ. The situation with two signals with different phases can be expanded to include more than two phases. Thus, if the signal phases are arranged in an orderly and predictable manner, three drivers can be used unambiguously to determine the position of a rotatable hand. If three equal-amplitude sine wave signals were equally spaced over 2π radians at 2π/3 intervals, when summed, the vector sum is zero. The above analysis is conventional and should be used as background for the present invention, a description of which ensues.
Drive Signals of the Present Invention
The present invention uses a phase modulation/demodulation technique to generate a resultant signal which is the superposition of a set of square waves. The drive signals are not sine waves, but are phase modulated square waves with two levels, V DD and V SS . Only two phase conditions of the carrier signal of each of the drives are used. The drive signals have two possible phase transition points: 0 and π radians (0° and 180°). Each drive has a 50% phase cycle (1/2T at 0 and 1/2T at π). A single drive S synchronously demodulated by a single gate GA results in a simple square wave E (FIG. 5).
By driving square waves which have only two phases 180° apart, the gate can have a long sample period. The gate is not closed until all transients have died out or been suppressed. Thus the concept is well suited to digital implementation.
In the present invention, there is utilized drive pairs consisting of driver signals and their complements. Three such pairs of signals are used. One pair (A, A) phase transitions at 0 with respect to a reference signal. Drive signal A assumes what is arbitrarily termed the 0-phase condition at 0. A second phase pair (B, B) transitions at 2π/3 (120°) with respect to the reference signal. A third phase pair (C, C) transitions at 4π/3 (240°). The above are referred to as phase modulated drive signals. The driver array electrodes are physically arranged (FIG. 5a) at such angular positions which correspond or correlate with the phase of their phase shift with respect to the reference signal. Thus:
______________________________________ PHYSICAL ANGLETRANSITION OR OF ELECTRODESDRIVE PHASE ANGLE RADIANS DEGREES______________________________________A 0 0 0°.sup.--C 1/3π 1/3π 60°B 2/3π 2/3π 120°.sup.--A π π 180°C 4/3 π 4/3 π 240°.sup.--B 5/3 π 5/3 π 300°______________________________________
This arrangement is also shown in FIG. 6.
In such arrangement in the absence of a hand or other dielectric variance, all phase pairs should balance, and there should be no signal on the center node or center electrode. The presence of a meter hand unbalances the coupling of the drives to the center electrode. If only signals A, B, and C and not their complements were present in the two-phase square wave condition, a non-zero signal would result. The output signal on the center electrode is strangely shaped (FIG. 6a). However, once it is buffered and synchronously detected as described in FIGS. 11a & 11b the resulting signal has six steps which always occur at the same places, although the levels will change as the position of the hand changes (See FIG. 7). From FIG. 6 it is seen that there are six different phase conditions, thus the "six step output." Each step, however, does not correspond to one of the six electrodes. Note that steps 1 and 2 are not adjacent but are symmetrically offset from the horizontal center line. It is the nature of such a periodic function that, in the absence of any perturbing factors, each step will have its symmetrical partner. The steps (FIG. 7) have been numbered to show this fact. The actual step levels will, of course, vary according to the actual position of the hand in front of the array.
Once the six-step signal has been generated, there are several methods of determining the hand angle. The signal can be filtered to a sine wave and the zero-crossing detected, as described hereinabove. If a counter is started at θ=0 and turned off by the zero-crossing detector, the count value is related to the phase angle. Similarly (and perhaps more reliably) a phase-locked loop can produce a square wave whose zero-crossing is closely related (offset by π/2) to the signal phase. This signal can be used to stop a counter as with the zero-crossing detectors. While either of the above types of detector may be used, it is preferred that the phase angle be calculated directly from the six-step signal levels in accordance with the techniques described hereinbelow.
Calculation of Phase Angle
The calculation of the phase angle of the signal directly from the six-step levels requires reading the step levels with an analog-to-digital converter and then performing an algorithm (FIG. 8). Contrary to the zero-crossing technique, this technique is not subject to component value changes. Additionally, the calculation method makes available a subsequent compensation based on the amplitude of the signal, which compensation will be related to the hand-to-transducer spacing. The calculation method is readily achieved with a microprocessor or microcomputer, although the method is compatible to a hardwired logic circuit.
The microprocessor must have some sort of data base representing the levels of the six steps, if it is to generate a hand position. In the system of the present invention, no negative voltages are used, although this is not a requirement. The signals have a center voltage of some value V, with the steps being either greater or less than V. In conjunction with the generation of the signal, there is utilized an 8-bit analog-to-digital converter to measure the levels and convert them into a digital representation in binary language. Due to the large variation in signal amplitude which results from the ordinary range of array-to-hand spacing, 10 bits of resolution is actually needed. To solve this problem there is utilized a variable gain prescaling amplifier in front of the step level acquisition circuit. (See FIG. 8). This amplifier can have a gain of 1, 2, 3, or 4, all under the control of the microprocessor. The system is designed so that the voltage level V is in the center of the A/D converter range (the 8-bit range is 0-255, so the center point is at 127), thus the signal is at V+ or - the step amplitude.
The step levels are acquired in the following sequence:
1. Gain is set to lowest level (1).
2. Levels are read in the order 1, 2, 3, 4, 5, 6.
3. Maximum and minimum levels are found (i.e. levels 3 and 4 in FIG. 7.
4. The gain (G) is set such that the signal is as large as possible without overflowing the A/D range.
5. The levels are reread in the same manner as step #2, above.
As stated above, and illustrated in FIG. 8, the levels are read into the microprocessor with an analog-to-digital converter. This device converts a voltage level into a binary code. An 8-bit A/D converter can resolve a voltage into one of 256 levels (2 8 ). As stated hereinabove, since 10-bit resolution is needed (1024 levels), the other 2 bits are generated with the variable gain preamplifier, which has an integer gain of from 1 to 4 (2 2 ) and is controlled by the microprocessor. The relationship of the signal acquisition elements is diagrammed in FIG. 8. The digital logic circuit controls the timing of the gate closing so that the proper six-step level is sampled at the proper time. The six steps are acquired in the order described hereinabove to have the maximum time available between samples to allow the A/D converter to perform its function and because the steps will be analyzed in pairs in the order taken into the A/D converter. After step 5 hereinabove, the six-step levels have been acquired in a digital form (binary code), and the gain being utilized has been stored. The same gain is used for all six steps. This is because the actual calculation of the hand position to follow is a function primarily of the ratios of the levels. The absolute amplitude is only critical in applying the amplitude compensation value, and does not require great precision. As this system is ratio based in most of the algoriths involved, while it required 10-bit resolution, only 8-bit accuracy is required. Thus, larger tolerances can be tolerated in the amplifier gain.
The microprocessor or embodiment of the algorithms has several reliability checks built thereinto. For example the algorithm checks the time required for the A/D converter to respond with data. If more than a specified amount of time is required, the microprocessor or algorithm presumes a fault condition and attempts to read the dial over. If there is a failure to respond the second time the system goes into a fault mode and does not attempt to read the dial in question or any subsequent dial. The algorithm also checks certain characteristics of the six-step levels. If the signal is too large (i.e. six-step levels which deviate too much from ±127.5), such signals will be too close to 0 or 255. This might cause the levels to be higher than the voltage which corresponds to 255, and then the A/D output would clip or limit, resulting in a "0" output. If the level is too low, the A/D output would tend to stay at 0. If the A/D level is too close to 0, then, the microprocessor presumes that the signal has either too high a voltage or too low a voltage, and it makes no difference which, as the result will be the same. The microprocessor steps through each of the stored six-step levels and checks to make sure that all are above some minimum value. If they are below that value, the entire set of values is rejected and the system attempts once again to read the six steps, going back through the gain setting part of the program. If the result is again faulty, the system presumes something is wrong and goes into the fault mode.
Each pair of steps (1 and 2, 3 and 4, 5 and 6) should be symmetrical about the center line. If they are not, it is presumed that some sort of noise got into the system or that there is a problem someplace in the electronic circuit. In either case, the signal is not acceptable. The symmetry of the step pairs is tested by summing the pairs together, which sum should equal 255. If the sum deviates from 255 by more than some specified amount the data is presumed to be faulty and the system tries to reread the steps. Again, if the second rereading fails, the system goes into the fault mode. The test is quite powerful and useful.
A test for too low a signal level is made later in the program during the amplitude compensation operation, as the signal level must be determined. If the signal is too low, the calculated hand position may be influenced by some residual or spurious signal and not due to the hand, so the system goes to the fault mode. These system checks do much to prevent a faulty reading from being transmitted.
Reduction to A, B, and C Vectors
As stated hereinabove, the six stepped signal at the central node is the superposition of three synchronously detected, square wave drive pair imbalances:
A=(h.sub.1 SA+h.sub.2 SA)
B=(h.sub.3 SB+h.sub.4 SB)
C=(h.sub.5 SC+h.sub.6 SC)
In the absence of a hand, we want A=B=C. Alternatively in the absence of a hand we want h 1 =h 2 , h 3 =h 4 , and h 5 =h 6 as h 1 thru h 6 are coupling variables reflecting the coupling between the center electrode and each component of the square wave devices due to the presence of the hand. It should be recalled that drive signal SA is the inverse of drive sign SA, etc. The presence of the hand causes the drives to be unequally coupled to the center electrode in the array, and hence, the ratio of imbalances is a function of hand position. If each of the phase pairs are synchronously detected separately, with each pair unbalanced to the same degree such tht SX>SX, there would result three square waves 120° apart (See FIG. 9).
The six steps are generated from the sum of these pairs such that:
S1=+A-B+C 1.
S2=-A+B-C 2.
S3=+A-B-C 3.
S4=-A+B+C 4.
S5=+A+B-C 5.
S6=-A-B+C 6.
In the above analysis S1 is step 1, S2 is step 2, etc., as reference to FIG. 7. The next step of the calculational technique is to take the six-stepped signal data and determine vectors A, B, and C. Since the six-stepped signal is symmetrical about the center line voltage, the step difference terms (SDX) can be defined to remove any small offset there may in the data. Thus:
SD1=S1-S2
SD2=S3-S4
SD3=S5=S6
If the above two sets of equations are then solved, the three drive waves appear as follows:
4A=SD1+SD3
4B=SD3-SD2
4C=SD1-SD2
Note that in all cases, the term "4×" appears, which is four times the vectors that are being solved for. The results, 4×, have the potential of being 9-bit values as each SDX has 8-bits resolution. There is no reason to divide the result by four, as that would reduce the precision. Thus, the valves are redefined:
A=4A
B=4B
C=4C
The values A, B, and C have now been calculated and can be treated as vectors 120° apart. Since A, B, and C are all 9-bit values, they can no longer be kept in 8-bit registers, therefore, they are maintained in 16-bit registers (two 8-bit registers). This allows signed calculations to be accomplished using the 2's complement method, which is easier in a microprocessor. Since 16-bit registers are now being utilized, the valves can be normalized for preamplifier gain. This is done by multiplying each step difference (SD) by 4 and dividing the result by the gain G. To multiply by 4 in a microprocessor, the contents of the register are simply shifted to the left two places.
Calculation of I and J Vectors
It should be noted that the three vectors (A, B, and C) define, and actually overdefine a resultant vector. The algorithm, as implemented in the microprocessor reduces the A, B, and C vectors to a single vector at some angle with some magnitude. This is done through consolidation first into two vectors which are at right angles to each other. Traditionally, I and J are defined as unit vectors which are orthogonal (90° or π/2 radians apart). Such vectors are the x and y axes in Cartesian coordinates. Mathematically, I and J are calculated as follows:
I=A-(B+C)/2
and
J=(B-C)×((√3)/2)
The calculation of I is straightforward and needs no explanation; however, the calculation of J utilizes a simplifying approximation for use in the microprocessor. Since (√3)/2=0.866 and 111/128=0.867 therefore: (√3)/2 is approximately equal to 111/128. This considerably simplifies things, as (B-C) can be multiplied by 111 and then divided by 128. Dividing by 128 in the microprocessor is done simply by shifting 7 binary digits to the right. The multiplication by 111 requires that a 24-bit wide results register be used on a temporary basis.
I and J have now been calculated on a signed basis. The next step is to separate the signs from the values, converting the values into absolute values with the signs stored as separate sign flags (SI for the sign of I and SJ for the sign of J for later use). To facilitate later calculation of the signal amplitude, two new variables are created which are I and J with reduced resolution so that the resulting values will fit into 8-bit registers, keeping in mind that I and J are, at this instant, 11-bit values. This step is easily done by shifting the values from I and J three bits to the right. All is now ready for calculation of the hand position.
Raw Count Generation
It is now desired to convert orthogonal vectors I and J with their sign flags into a hand position. For reasons that will become clear later, the circle is divided into 640 parts or counts (which are called Wason Counts or WC's). The angle of the resultant vector is defined by (signed) I and J using the arctangent. This calculation is broken into two parts: first, finding the angle with respect to the I axis, then finding the quadrant in which the angle lies. In FIG. 10 there is illustrated a conventional labeled quadrant diagram with 45° bisectors.
As is well known the tangent of any angle is the ratio of J to I (TAN θ=J/I). Thus, to find the angle θ, it is necessary to determine the angle whose tangent is J/I (arc TAN J/I). Where I is equal to or greater than J, this is no particular problem, however, where J is greater than I, then θ=90°-Arctan (I/J). When I equals J, θ equals 45°. Thus, each quadrant can be broken into two parts. The quadrant is determined by the signs of I and J, which have been stored as SI and SJ, the sign flags. The quadrant is then determined as follows:
______________________________________SI SJ Quadrant______________________________________+ + I- + II- - III+ - IV______________________________________
First, the microprocessor program determines if I is less than J, a swap flag (SF) is set and I and J are switched. The microprocessor then finds and equivalent to the arctangent of J/I. Since the circle has been arbitrarily, but with ultimate purpose, divided into 640 parts, 45° is equal to 80 counts. Thus, the arc-tangent is in non-standard units. By virtue of the process, J is always less than or equal to I, hence a simple division would result in a value less than or equal to 1, a value not suited to integer arithmetic. Thus, the J value is multiplied by 256 by shifting it 8 bits to the left. This is done by concatenating (joining or linking together) an 8 bit word of zeros to the right. Thus, when J is divided by I, the resultant answer will be a value ranging from 0 to 255, a suitable range for binary logic. The tangent equivalent K is now calculated (K=256×J/I). This value can be converted into angular equivalent units utilizing a sucessive approximation procedure.
Successive Approximation of the Arctangent
The tangent equivalent K is converted into angular equivalent units (WC's) through the use of a successive approximation algorithm which utilizes an 80 point sequential table. The table is generated by the following simple BASIC program:
100 PI=3.141592654: REM===CREATE LOOK UP TABLE===
110 D=2×PI/640
120 DIM VA(79): REM===DIMENSION ARRAY===
130 PRINT TAB (6); "W"; TAB(15); "INTEGER"
140 FOR W=0 to 79
150 T=D/2+(WxD): REM===HALF-WAY BETWEEN W'S===
160 LU=256xTAN(T)
170 VA(W)=INT(LU+0.5): REM===ROUNDOFF TO INTEGER===
180 M1=7-LEN(STR$(W)
190 M2=20-LEN(STR$(VA(W)))
200 PRINT TAB(M1); W; TAB(M2); VA(W)
210 NEXT W
220 END: REM===END OF LOOK UP TABLE CREATION===
W=angle in WC's (remember, 2π=640WC's)
T=an angle half way to the next W
VA(W)=integer value of K
This results in a table of values set forth in FIG. 11 of the drawings.
Successive approximation is a process of converging on a value or solution by making a series of guesses within a set of rules. Two limits are defined, an upper and lower limit; the designated value is then compared to the value stored in the register midway between the upper and lower limits. If K is greater, then the midpoint becomes the new lower limit. Conversely, if K is less than the midpoint, then the midpoint pointer becomes the new upper limit. The process is repeated until a single value is converted upon. The following variables are defined:
K=Our calculated arctangent equivalent
WP=Current center pointer and final output word,
UP=Upper pointer,
LP=Lower pointer,
VA(XP)=Value in register at the pointer location X.
Keeping in mind that the goal is to determine the WP, the following procedure is used in a successive approximation subroutine (SAS):
1. If K<1, then WP=0, then exit SAS
2. If K>253 the WP=80, then exit SAS
3. Set UP=79
4. Set LP=0
5. Set WP=(UP+LP)/2 (take integer value)
6. Get VA(WP)
7. Is K>VA(WP)?
A. If yes, LP=WP (Redefine lower pointer)
B. If no, UP=WP (Redefine upper pointer)
8. is (UP-LP)>1?
A. If yes, then return to #5 above
B. If no, then WP=UP, then exit SAS.
Note that there are three places that the subroutine can be exited: after step 1, after step 2, or after step 8B. In any of these three cases, WP is defined. The maximum number of times that it is necessary to go through the loop defined by steps 5 through 8A is seven. This is a very efficient method of searching through the table of arctangent values to find the one which most closely approximates K. The "address" (WP) of the value is the angular equivalent needed to proceed with the calculation of the hand position.
Sector and Quadrant Selection
Earlier in the processor program, there was stored a value (SF) to indicate whether or not the I/J vectors had been swapped. That value is now used to determine which sector of the quadrant (FIG. 10) WP is in. In all cases, if the I and J values were not swapped, WP lies in the sector closest to the "I" axis. Conversely, if a swap of I and J was made, the resultant vector or WP lies in the sector closest to the "J" axis. The rules are simple. If the swap flag (SF) is clear, then WP=WP. Conversely, if the SF is set, then WP=160-WP.
Now the vector can be placed in the proper quadrant and the value of W calculated with a decision tree based on the signs of I(SI) and J(SJ):
If sign of SI is + (or zero) and:
If sign of SJ is + (Quadrant I), then W=WP, exit
If sign of SJ is - (Quad. IV), then W=640-WP), exit
If sign of SI is - and:
If sign of SJ is + (Quad. II), then W=(320-WP), exit
If sign of SJ is - (Quad. III), then W=(320+WP), exit
There has now been determined a value W which is in the range of 0 to 639. Before being converted into a final dial digit reading, some compensations must be applied.
Compensations
On the value W which has been determined as being representative of the hand position, there are now three types of compensations to be performed. Those are offset, amplitude, and inter-dial compensations. Various factors cause W not to be 0 when the hand is apparently in a 0 position. That is, the relationship between W and the true hand position may have some deviation. One type of deviation may be that, because of manufacturing considerations the physical layout of the electrode array is such that when the hand is in the 0 position, the calculated value W is offset by some fixed amount, which also applies to all values around the dial. This is referred to as an "offset" compensation and is adjusted through a baseline adjustment. Another type of deviation which may occur is a function of the distance between the hand and the array, called the "z" spacing to correspond to the traditional Z axis in a polar coordinate system. To compensate for the "z" effect an adjustment value, based on the signal amplitude, is applied to the detected signal W. Finally, each dial reading must be adjusted so that information from the previous dial readings are used to reduce or remove effects of small errors in hand alignment (physical alignment) or electronic process (noise and non-linearity). This is referred to as "inter-dial" compensation and will be discussed hereinafter.
Offset compensation is a baseline correction for the gross rotation of the array pattern. The calculated hand positions have an average offset from the true hand position. This offset is adjusted by adding a constant value (OS) to the detected signal count W. Therefore, W=W+OS. The offset compensation value is generated when the amplitude compensation table is generated, as OS defines a starting point to be used on the amplitude compensation curve.
Amplitude Compensation
The offset changes as the spacing between the hand and the array changes. Fortunately, the amplitude of the six-step signal is a function of the spacing between the meter hand and the driven array. It has been found that the relationship between the offset and the amplitude (RA) may be approximated with the following equation:
Total Offset=a+b(RA)+c(1/RA)
a, b, and c are constants which are generated from experimental data. This experimental data involves generating amplitudes (RA) and uncompensated W's at a number of known hand positions at a number of known spacings (z's). From these values the constants a, b, and c are generated by multiple regression techniques.
The total offset could be calculated directly; however, it would require a considerable amount of memory space and time in the microprocessor based system, so a lookup table is used. The amplitude is calculated from vectors I and J as follows:
RA=√(I.sup.2 +J.sup.2).
Both I and J are 11-bit values, hence squaring and summing them results in a 22-bit value. This is too cumbersome to work with, so rather than using the entire amplitude RA, a truncated version of the amplitude is used. Recall that a truncated version of vectors I and J (referred to as IV and JV) were generated earlier in the process. These are both 8-bit values, and now there is defined a new value RS which is the sum of the squares of these values, has a maximum bit size of 16, and is always positive.
The range over which the amplitude compensation is to be performed is selected and the offsets are calculated at points midway between the adjacent values on a lookup table. Instead of the equation using RA, there is generated an equivalent equation using the square root of RS. Thus,
Total Offset=a+b(√RS)+c(√RS)).
This equation is solved for RS as a function of total offset (TF), a, b, and c with the following result:
RS=[(((TF-a)+((a-TF)-4bc)))/(2b)].sup.2
From the results, there is generated a list of values of RS as a function of TF at intervals which are used in the lookup table. The minimum RS value permitted was selected as the bottom of the lookup table and this point is defined as P(min). The lookup table address of the stored values of RS are equal to the corresponding TF-(1/2 the interval between TF's). The minimum TF was set as the base offset (OS), above. The lookup table is used to generate the amplitude compensation value (AC).
The program uses the lookup table as follows:
1. Calculate RS
2. Set pointer at P(min)
3. Compare the Actual RS with the value in TF(P)
If Actual RS is less than value in TF(P),
signal is too small, go into fault mode
4. Set pointer at TF(P)
5. Compare the Actual RS with the value in TF(P)
If RS is less than lookup table value at
TF(P) then AC=TF(P)
Add AC to WC (WC=WC+AC); Exit subroutine
If RS is greater than value stored in TF(P)
go ahead to 6
6. See if P is equal to P(max)
If P is equal to P(max), then
AC=TF(P)
Add AC to WC (WC=WC+AC); Exit subroutine
If P is less than P(max), then
Increment pointer P
Go back to #4, above
Having compensated for all of the above, the count is now as accurate as possible for a single dial.
Inter-Dial Compensation
If the position of a single dial pointer were infinitely accurate, and it could be reliably resolved with the measuring system, there would be no need to have more than one dial on a meter register. The only necessary hand would be the most significant digit, which would be read with the necessary resolution. This is obviously not possible. There is back lash in the gear train, and the encoding technique obviously has limits to its accuracy. It is therefore necessary to actually read all of the hands on a register. Given that there may be inaccuracy in determining the true position of the hand, we must cause each hand to be consistent with the previous (less significant) hand readings. Reference is now made to U.S. Pat. No. 4,214,152 where this problem is discussed and solved according to an earlier technique.
Consider two adjacent dials D 1 and D 2 for which D 1 is the least significant of the two dials and D 2 is the most significant of the two dials. Each of the dials include decimal digits arranged in a circular pattern from 0 to 9. The distance between adjacent digits is then 36 degrees. Assuming each dial could be resolved to 100 parts with an accuracy of ±3 parts, we can read the digits to 0.1±0.3. Now, presume the two dials have just been read with the following values:
D.sub.1 =9.2,
D.sub.2 =4.1.
Is the reading 49 or 39? How does an encoder determine what the right reading is? The correct value for D 2 can be resolved by examining the least significant dial D 1 . Dial D 2 is very close to the transition from "3" to "4". Thus, it can be seen that it should be read as a "3", for dial D 1 is close to, but has not yet passed the transition from 9 to 0, which would cause the next dial to logically transition to the higher digit.
To solve this problem an adjustment factor derived from the reading of the previous dial is added to remove this potential ambiguity. It is important to note that the adjusted reading of the previous dial is used in determining this adjustment factor: thus an adjustment factor determined in reading a previous (less significant) adjacent dial is applied to the reading of a subsequent (more significant) dial. More formally the generation of an interdial correction factor for the more significant adjacent dial is always performed after the generation of the correction factor from the previous dial. The determination of all such correction factors proceeds as follows. The transition of the more significant digit of a digit pair should occur upon the transition of the less significant dial from 9 to 0. The value of the less significant digit contains the correct information to resolve possible ambiguities of the more significant digit. In the following discussion these terms will be used:
Terms relating to desired output format (or number base system):
D=number of digits into which a dial is divided, normally equal to N,
D A =adjusted digit value,
D'=digit value, less significant dial,
D"=digit value read before interdial correction, one level of significance higher than D',
N=total number of digits per dial, and gear ratio between adjacent dials,
R=reference zero,
A=digit adjustment value,
A"=adjustment value determined from less significant dial reading, D', to be applied to D",
A d =adjustment value in digitized levels,
Terms relating to internal reading and correction process prior to output:
d=number of digitized levels into which a dial is resolved,
d', d"=digitized level value for a particular hand or shaft position,
d A ', d A "=adjusted digitized level value,
n=dial number being read.
It is desirable and useful to add (algebraically) an adjustment to the more significant digit to increase the probability of having a correct digit reading and to cause a sharp transition as the less significant digit undergoes a transition to zero. This adjusted value of the more significant digit can be expressed:
D.sub.A "=D"+A" (Eq. 1)
Presume that each digit dial can be resolved into d, digitized levels, and that for initial considerations, d is a large number approaching, for practical purposes, infinity; note that resolution is merely the number of digitized levels, and is not the accuracy of the determination of hand position, although it represents the upper limit of accuracy for a single reading. Digit value, D', is related to the digit levels, d', by the ratio: ##EQU3## It is readily apparent that the maximum mechanical error of the more significant hand is plus or minus one-half digit. Thus, as the least significant digit approaches the transition from (in resolved digitized levels) d'=d to d'=0, or in decades, from 9.9999 to 0.0000) if, at d'=d, the equivalent of one-half digit were subtracted from the more significant digit, and if, as the less significant digit passes the transition, one-half digit were added to the more significant digit, readout would undergo an abrupt transition from one digit to the next higher digit. Obviously, if the maximum error of hand reading is plus or minus one-half digit, then when the least significant digit is at the point farthest from next significant digit transition (i.e., 5 on a decade system), then adding or subtracting one-half digit to or from the next significant digit is apt to cause an error. When D'=1/2N (shaft rotation is 180° from the next significant digit transition), the adjustment, A", should be zero. The optimal adjustment for a decimal system can be written: ##EQU4## This equation has the desired property of having an absolute maximum when D' is O or D, and a minimum when D'=1/2N. Note that A" D is derived from D', the less significant digit and applied to D", the more significant digit. The actual adjustment must be made in terms of resolved or digitized levels and must differentiate between slightly before and slightly after a digit. Equation (3) thus becomes (using equation (1)): ##EQU5## the quantity comprising the correction factor to be added from the previous less significant dial and to be independently determined for the next more significant dial. [Note (1) that (d-1/N) 1/2 is used rather than (d/N) /1/2 because d is not a continuous variable; (2) that strictly speaking Eq. 4 is equivalent to (nd/2-1)1/N which approaches d/2 in the limit as n→∞].
From the foregoing analysis a compensation technique has been developed based on an equation derived for the maximum possible compensation achievable of the n th dial which will provide a binary compensation value utilizing the information from all previous dials. The desired digit reading of the n th dial, D n , shall be called R n , such that: ##EQU6## The terms are defined as: n=Dial number (1=Least significant dial),
C=Maximum permissible counts or states (again, this system uses 2560),
WC n =Number of counts for Dial n (0-2559),
R i =Reading (decimal) for i th dial (integer from 0 to 9)
R n =Reading (decimal) for n th dial (integer from 0 to 9)
R n-1 =Reading (decimal integer) for (n-1) th dial,
INT=Integer value of term which follows, truncate to decimal point.
The equation (above) has three terms:
WC n , the raw counts,
C-1/20, a constant term and, ##EQU7## Each of the terms is multiplied by 10/C. The second, constant term is always the same, so no special program manipulations are required. Note that the "Y" term is generated from the previous less significant dial digits (R i ), thus the Y term generated before this dial (R n ) is already compensated.
The addition of the three factors above is accomplished in a simple sequence. For a decimal based system, the flow chart of FIG. 21 outlines the procedure. For the binary system described herein, the following procedure is used:
1. WC n is shifted left two places; this is the same as multiplying it by 4,
2. To the result is added 128, which is 640/20×4,
3. From this a value Y 1 is subtracted; the result is W,
4. Wrap around is checked:
if W is greater than or equal to 2560, then 2560 is subtracted from it,
if W is less than 0 then 2560 is added to it.
At this point there has been created a variable W for each dial, which variable has a value from 0 to 2559. Steps 2 and 3 above performed the inter-dial compensation (IDC), but in a number based from 0 to 2559 (2560 possible values). It can be seen that WC is selected from the family of values defined by the equation: WC=2560/(2 m ) for integer values of m from 0 to 8. Selection of m is based on the needs of the particular situation. For this application m=2. This number is 12 bits long. Now it must be converted to a decimal value and truncated, after which a new IDC value Y 1 can be generated.
Conversion to BCD
It is now desired to send out the final digit value for the dial in ASCII code. For the numerical values (0-9) this means that the first 4 bits from the binary coded decimal (BCD) of the number. This is simply the binary equivalent of the number in 4 bits (e.g. 0=000; 1=001; 2=0010; 3=0011; 4=0100; etc.). This is then combined with three control bits and a parity bit (P011). P is the parity bit which allows checking on the receiving end for data transmission errors.
It will be recalled that there has been generated a 12-bit value W for the dial reading. This 12-bit value will be truncated to the digit value R n . By virtue of the manipulations which have been performed, the highest 4 bits of the 12-bit value are the BCD value of R n . Since the manipulations have been accomplished in an 8-bit microprocessor, it is an easy matter to drop out the low byte Wl (which is the lowest 8 bits), so that this information is not transmitted.
Returning now to the generation of Y 1 the IDC value the value just generated for the dial digit is used to generate a new Y 1 for the next dial. The following mathematical operation is performed:
Y.sub.1 =((R.sub.n ×256)+Y.sub.1)/10
Now this is done as follows:
1. multiply the existing dial reading, R n , by 256,
2. add the result to the existing Y 1 ,
3. divide the result by 10; this is the new Y 1 , to be used on the next dial digit.
Obviously, the value of Y 1 will depend on the digit values of all previous dials. This provides the maximum possible compensation and is to be desired. It does, however, require that the process start off right for the first digit (representing least significant digit) generated. There is sufficient resolution that, if the accuracy permits, there can be generated from the reading of the least significant dial a 1/10th digit. This is done whether or not the value is in the output message. The least significant dial must also start off with the proper initial value of Y 1 .
Before reading the least significant dial, the value of Y 1 is initialized to 128. Note that in calculating the 2560 count value of dial 1 (the least significant dial) there is first added 128 to the reading, and then subtract the initialized value of Y 1 (128) from it. In other words, it is unaffected. The process is as follows:
1. initialize Y 1 to 128,
2. generate C n ,
3. calculate the 12-bit value (W) in 2560 counts, including the IDC using Y 1 ,
4. save the high byte (W h , R n for dial 1) as W s
5. multiply W l by 10, which is the new 12 bit word, W,
6. take the high byte, W h of the new value of W for the digit value, R n , of 1/10 th of the least significant dial,
7. generate a new value of Y 1 , as above,
8. check a jumper on the microprocessor port to see if the 1/1 dial is to be output;
if this is not to be output then clear the new W h to all zeros,
if this is to be output, then leave the new W h alone,
9. shift W h into the digit output routine in which the upper nibble is fashioned (P011) and attached to form the ouput byte,
10. retrieve W s , redefine it as W h ,
11. generate Y 1 as above,
12. shift W h into the digit output routine in which the upper nibble is fashioned (P011) and attached to form the output byte,
13. proceed to read the remaining dials in the normal fashion.
There has thus been described in detail a preferred embodiment of the present invention. It is obvious that some changes might be made without departing from the scope of the invention which is set forth in the accompanying claims. | A transducer formed of one or more electrode arrays is positioned in confronting relation and parallel to the plane of rotation of one or more rotating members. A plurality of phase modulated, two-phase, square wave drive signals of the same amplitude and frequency are applied to each electrode. The signals are combined at a central node or electrode to form, as a result of the signal, the superposition of the algebraic sum of all drive signal pairs. Samples of the resultant signal taken at the same frequency and of a duration of less than one-half the duration of the drive signal period provide a multi-step, synchronously detected signal. The detected signal is a multi-step approximation to a sine wave, the phase angle thereof relative to a timing point being proportional to the angular position of the rotating member. The amplitudes and phase shifts of the multi-step detected signal are then reduced to a plurality of vectors, from which two orthogonal vectors are produced which may be mathematically reduced to the amplitude and phase angle of the aforesaid sine wave. The phase angle is transformed or converted into a binary representative of the hand position. | 6 |
RELATED APPLICATION
This application claims the benefit of priority of provisional application No. 60/377,964 filed May 7, 2002.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to medicine and biomedical research. More specifically, the present invention relates to expression systems to produce small hairpin RNAs (shRNAs) or interfering RNAs (siRNAs), collectively called siRNA in this application, in eukaryotic cells and methods for expressing siRNAs in eukaryotic cells. The present invention also relates to the use of the expression systems as medicinal products.
2. Related Art
RNA interference (RNAi) is a process of sequence-specific, post-transcriptional gene silencing (PTGS) in animals and plants initiated by double-stranded RNA (dsRNA) that is homologous to the silenced gene. It is an evolutionarily conserved phenomenon and a multi-step process that involves generations of active siRNAs in vivo through the action of a mechanism that is not fully understood. RNAi has been used as a reverse genetic tool to study gene function in multiple model organisms, such as plants, Caenorhabditis elegants and Drosophila , where large dsRNAs efficiently induce gene-specific silencing. In mammalian cells dsRNAs, 30 base pairs or longer, can activate antiviral response, leading to the nonspecific degradation of RNA transcripts and to a general shutdown of host cell protein translation. As a result, the long dsRNA is not a general method for silencing specific genes in mammalian cells. Recently, various siRNAs that were synthesized chemically or generated biologically using DNA templates and RNA polymerases have been used to down regulate expression of targeted genes in cultured mammalian cells. Among approaches used, it is highly desirable to use DNA constructs that contain promoters of transcriptions and templates for siRNAs to generate siRNAs in vivo and in vitro. Though several different promoters have been adapted in such DNA constructs, types of promoters used remain limited to, Type III RNA polymerase III (Pol III) promoters, such as the U6 promoter and the H1 promoter, and promoters that require viral RNA polymerases, such as the T7 promoter. The present invention provides methods and designs to produce gene expression suppression agents that greatly expand potential usages of siRNAs.
SUMMARY OF THE INVENTION
The present invention relates to methods to produce gene expression suppression agents for expression of siRNAs in mammalian cells. Such agents contain RNA polymerase III (Pol III) transcription promoter elements, template sequences for siRNAs, which are to be transcribed in host cells, and a terminator sequence.
The promoter is any native or engineered transcription promoter. As examples of such promoters (not intended on being limiting), in one embodiment, the promoter is a Type I Pol III promoter, while in another embodiment, the promoter is a combination of Type I Pol III promoter elements and Type III Pol III promoter elements. In other embodiments other types of promoters are present.
The targeted region of siRNA is anywhere on a transcript of any sequence in eukaryotic or viral genomes. The terminator is any native or engineered sequence that terminates the transcription by Pol III or other types of RNA polymerases.
Such gene expression suppression agents are delivered into eukaryotic cells, including (but not limited to) mammals, insects, worms and plants, with any routes, procedures or methods, such as (but not limited to), in vivo, in vitro, ex vivo, electroporations, transfections or viral vector transduction.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a schematic representation of the embodiment for generating siRNA in mammalian cells using vertebrate Type I Pol III promoters. Specifically, FIG. 1 is a schematic representation of a strategy for generating siRNA in mammalian cells using vertebrate Type I Pol III promoters (5S rRNA gene promoter and others). “A Box”, “C Box”, “D Box” and “IE” are Pol III promoter elements, “+1” is an initiation site of transcription, “Tn” is a termination site of the Pol III promoter transcript, and the arrow indicates the orientation of transcription. The siRNA template consists of sense, spacer, antisense and terminator sequences, and generates a hairpin dsRNA when expressed. “Sense” is a 17-23 nucleotide (nt) sense sequence that is identical to that of the target gene and is a template of one strand of the stem in the hairpin dsRNA. “Spacer” is a 4-15 nt sequence and is a template of the loop of the strand of the stem in the hairpin dsRNA. “Terminator” is the transcriptional termination signal of five thymidines (5 Ts).
FIG. 2 is a schematic representation of the embodiment for generating siRNA in mammalian cells using vertebrate Type III Pol III promoters (U6 gene promoter, H1 RNA gene promoter, Y1 gene promoter, Y3 gene promoter, RNase P gene promoter and others). DSE, distal sequence element of Pol III promoter: PSE, proximal sequence element of Pol III promoter; TATA, a promoter element; +1, initiation site of transcription; the arrow indicates the orientation of transcription; siRNA Template, a 43-66 nt engineered insert that is the template for generating a hairpin dsRNA against a target gene; Sense, a 17-23 nt sense sequence from the target gene, template of one strand of stem in the hairpin; Spacer, a 4-15 nt sequence, template of loop of the hairpin; Antisense, a 17-23 nt antisense sequence, template of the other strand of stem in hairpin; Terminator, the transcriptional termination signal of 5 thymidines (5 Ts).
FIG. 3 is a schematic representation of the embodiment for generating siRNA in mammalian cells using an engineered Pol III promoter containing the elements in both Type I and Type III promoters. “DSE” is a distal sequence element of Type III Pol III promoter. “PSE” is a proximal sequence element of Type III Pol III promoter, “TATA” is a Type III Pol III promoter element. “A Box,” “C Box” and “IE” are Type I Pol III promoter elements. “+1” is an initiation site of transcription. “Tn” is a termination site of the Type III Pol III promoter transcript. The arrow indicates the orientation of transcription. The siRNA template consists of sense, spacer, antisense and terminator sequences, and generates a hairpin dsRNA when expressed. “Sense” is a 17-23 nt sense sequence that is identical to that of the target gene and is a template of one strand of the stem in the hairpin dsRNA. “Spacer” is a 4-15 nt sequence and is a template of the loop of the hairpin dsRNA. “Antisense” is a 17-23 nt antisense sequence and is a template of the other strand of stem in hairpin dsRNA. “Terminator” is the transcriptional termination signal of five thymidines (5 Ts).
FIG. 4 is a schematic representation of the embodiment for generating siRNA in mammalian cells using two vertebrate Type I Pol III promoters that drive transcriptions of sense siRNA and antisense siRNA separately. “A Box”, “C Box”, “D Box” and “IE” are Pol III promoter elements. “+1” is an initiation site of transcription. “Tn” is a termination site of the Pol III promoter transcript. The arrow indicates the orientation of transcription. “Sense siRNA Template” is a 22-28 nt engineered insert that is the template for generating a sense single-stranded RNA (ssRNA) against a target gene, and consists of sense and terminator sequences. “Antisense siRNA Template” is a 22-28 nt engineered insert that is the template for generating an antisense ssRNA against a target gene, and consists of antisense and terminator sequences. “Sense” is a 17-23 nt sense sequence that is identical to that of the target gene and is a template of one strand of the stem in the hairpin dsRNA. “Spacer” is a 4-15 nt sequence and is a template of loop of hairpin dsRNA. “Antisense” is a 17-23 nt antisense sequence and is a template of the other strand of the stem in the hairpin dsRNA. “Terminator” is the transcriptional termination signal of five thymidines (5 Ts).
FIG. 5 is a schematic representation of the embodiment for generating siRNA in mammalian cells using an engineered T7 polymerase and T7 promoter. “Promoter” is a constitutive or context-dependent promoter such as an inducible promoter or a cell type specific promoter; “T7 Polymerase Gene” is a sequence coding for T7 polymerase. T7 promoter is a T7 promoter. “+1” is an initiation site of transcription. The arrow indicates the orientation of transcription. The siRNA template consists of sense, spacer, antisense and terminator sequences, and generates a hairpin dsRNA when expressed. “Sense” is a 17-23 nt sense sequence that is identical to that of the target gene and is a template of one strand of the stem in the hairpin dsRNA. “Spacer” is a 4-15 nt sequence and is a template of the loop of the hairpin dsRNA. “Antisense” is a 17-23 nt antisense sequence and is a template of the other strand of stem in the hairpin dsRNA. “Terminator” is an engineered terminator for T7 polymerase.
FIG. 6 is a schematic representation of the embodiment for generating multiple siRNAs in mammalian cells using a single multiple transcription unit construct. “Unit” is a transcription unit that contains a vertebrate Type I Pol III promoter and a siRNA template. “A Box”, “C Box”, “D Box” and “IE” are Pol III promoter elements. “+1” is an initiation site of transcription. “Tn” is a termination site of the Pol III promoter transcript. The arrow indicates the orientation of transcription. The structure of siRNA template consists of sense, spacer, antisense and terminator sequences, and is an engineered insert that is the template for generating a hairpin dsRNA against a target gene. “Sense” is a 17-23 nucleotide (nt) sense sequence that is identical to that of the target gene and is a template of one strand of the stem in the hairpin dsRNA. “Spacer” is a 4-15 nt sequence and is a template of the loop of the hairpin dsRNA. “Antisense” is a 17-23 nt antisense sequence and is a template of the other strand of stem in hairpin dsRNA. “Terminator” is the transcriptional termination signal of five thymidines (5 Ts). The multiple siRNAs may target a single region on one gene, different regions on one gene, or one region on each of many genes.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description is provided to aid those skilled in the art to use the present invention. It should not be viewed as defining limitations of this invention. The present invention is directed to selectively suppress expression of genes targeted within mammalian cells by making and using DNA constructs that contains RNA polymerase III (Pol III) transcription promoter elements, template sequences for siRNAs, which are to be transcribed in host cells, and a terminator sequence. The promoter is any native or engineered transcription promoter. In one embodiment, the promoter is a Type I Pol III promoter. The essential elements of Type I promoter, such as “A Box”, “C Box”, “D Box” and “IE” are included in the DNA construct. In this embodiment, siRNA template is arranged between the “D Box” and “A Box”. In another embodiment, the promoter is a combination of Type I Pol III promoter elements and Type III Pol III promoter elements. In this embodiment, the essential elements of both types of promoters, such “A Box”, “C Box”, and “IE” of Type I promoter, as well as “DSE”, “PSE” and “TATA” of Type III promoter are included in the DNA construct, with “DSE”, “PSE” and “TATA” in the upstream region of “+1” position, “A Box”, “C Box”, and “IE” in the down stream region of the “+1” position. Any promoter that is functioned in the mammalian cells is suitable to be used in this invention. Modifications, such as adding inducible or enhancing elements to exiting promoters, is suitable to be used in this invention.
The targeted region of siRNA is anywhere on a transcript of any sequence in mammalian or viral genomes. In some embodiments, templates for siRNA code for RNA molecules with “hairpin” structures contains both sense and antisense sequences of targeted genes. In other embodiments, the template for sense sequence and the template for antisense sequences are driven by different promoters.
The terminator is any native or engineered sequence that terminates the transcription by Pol III or other types of RNA polymerases, such as, but without being limited to, a stretch of 4 or more thymidines (T) residues in a DNA molecule.
Any transcriptional unit containing a promoter, a template for RNA and a terminator, is suitable to be constructed with one other unit, or multiple units, in a DNA molecule as an agent. In one embodiment, a multiple units construct is showed. More than one kind of the gene expression suppression agents (DNA molecules) are suitable to be introduced into mammalian cells together. The siRNAs generated within the same mammalian cell by these multiple units or co-introduction approaches provide agents ability to target one specific region in one targeted RNA molecule, multiple regions in one targeted RNA molecule, or multiple regions in more than one RNA molecules.
Such DNA constructs as indicated above can be constructed as a part of any suitable cloning vectors or expression vectors. Then the agents can be delivered into cells, tissues or organisms with any routes, procedures or methods, such as in vivo, in vitro, ex vivo, injection, electroporations, transfections or viral vector transduction.
EXAMPLES
Example 1
Cloning of the Human 5S rDNA Regulatory Sequences
The promoter chosen for the experimental design proposed below is the human 5S rRNA gene. The sequence is available in the database: Genbank Accession Number X12811. 5S rRNA promoter contains downstream Boxes A and C and upstream Box D. In FIG. 1 , the 49 nt sequence between the initiation site of the 5S rRNA and Box A is proposed to be replaced with interfering RNA sequence. Generation of a cassette containing both upstream and downstream boxes will be carried out in two steps. Cloning of the Box A and C can be achieved by chemical synthesis. The upstream Box D is done by PCR.
Cloning of the recombinant 5S rDNA Box D is carried out through PCR using forward primer (AACggatccaaacgctgcctccgcga) (Seq. 1) and reverse primer (TAGACGCTGCAGGAGGCGCCTGGCT) (Seq. 2), which can then be subcloned into BamHI and Pstl sites of pBS2SK. The Box A/C can be synthesized as top strand (AGAAGACGAagctaagcagggtcgggcctggttagtacttggatgggagaccgcctgggaataccggg tgctgtaggcttttg) (Seq. 3) and bottom strand (TCGACAAAAAGCCTACAGCACCCGGTATTCCCAGGCGGTTCTCCCATCCAA GTACTAACCAGGCCCGACCCTGCTTAGCTTCGTCTTCT) (Seq. 4), which are then annealed and subloned into EcoRFV and SalI sites downstream of the cloned Box D. The annealed DNA fragment is engineered with a BbsI site.
Example 2
Insertion and Cloning of RNAi Sequence
The RNAi cassette will be synthesized as two strands and cloned between Pstl and BbsI sites. The RNAi cassette is designed as follows:
(Seq. 5) 5′ GC(N19)TTTCGG(61N)TTTTT 3′ (Seq. 6) 3′ ACGTCG(61N)AAAGCC(N19)AAAAATCGA 5′
N19 is the 19 nt target DNA sequence selected from the transcribed region of a target gene. 61N is the reverse and complementary strand of N19. Transcription is initiated from the first base of N19 target sequence and terminated at the poly T.
Example 3
Targeting ErbB2/Her2 in Breast Cancers
ErbB2/Her2 gene is amplified in about 30% of breast cancers in humans, causing fast growth and metastasis of cancer cells. Herceptin, an antibody made by Genentech that blocks ErbB2 functions, is the only agent used by ErbB2-positive breast cancer patients that slows progression of metastatic breast disease and increases overall survival for patients given the drug along with standard chemotherapy compared to chemotherapy alone. Generation of siRNAs targeting ErbB2 developed with this invention should provide an alternative treatment.
Example 4
Targeting BCR-Abl tyrosine kinase in chronic myelogenous leukemia (CML) and other cancers. BCR-Abl is a fusion gene product that frequently occurs in CML. STI571, also called Gleevec developed by Novartis, is a newly approved anticancer agent to target BCR-Abl in CML. Generation of siRNAs against the fusion gene BCR-Abl, without interfering with the normal expression of either BCR or Abl gene, developed with this invention should have great potential for gene therapy to treat CML.
Example 5
Targeting Hepatitis B Virus (HBV)
Using this invention to target different sites of the HBV genome will provide a potent gene therapy to treat hepatitis B infected patients.
Example 6
Targeting Human Immunodeficiency Virus Type 1 (HIV-1)
Using this invention to target different sites of the HIV genome will provide a potent gene therapy for HIV infected patients. A multiple units agent simultaneously targeting multiple sites, such as env, gag, pol, vif, nef, vpr, vpu and tat, may be suitable to address resistances resulted from mutations of the HIV genome. | A method is provided for making gene suppression agents to be used in eukaryotic cells by using a recombinant DNA construct containing at least one transcriptional unit compromising a transcriptional promoter, a template sequence for making a RNA molecule, and a transcriptional terminator. Mechanisms of the RNA mediated gene suppression include, but are not limited to, RNA interferences (RNAi). The use of the agents as tools for biomedical research as well as medicinal products is also disclosed. | 2 |
BACKGROUND
1. Technical Field
The present invention relates to machine tools and more particularly to a vise stop configured to assure repeatability in the placement of a work piece in relationship to the machine tool.
2. Background of the Invention
Oftentimes in machining operations, it is necessary to perform repetitious machine tool functions on a plurality of substantially identical parts for mass producing a particular piece or part. Numerically or computer controlled milling machine tools, including mills and lathes, are highly adapted to this type of function. Nevertheless, each new work piece must be set up with particular care to assure that reference surfaces are positioned substantially identically, that is, positioned in the same X, Y & Z axes so as to assure repeatability of the machining operation and quality of the final product.
In most machining environments today, a Y axis may be fixed by setting the jaws of a machine tool vise in a specific location and then setting the vice so that the fixed jaw becomes a reference point on the Y axis. Similarly, the seat of the vice, once the vice is installed and bolted to the table of the machine tool, establishes a repeatable reference for the Z axis. Location then of the work piece on the Y axis and repeatability of this location has remained challenging.
A number of solutions have been proposed with limitations. In some instances, devices lack rigidity and may loose their ability to produce accurate positioning of piece after piece in relationship to the cutting tool. This is particularly the case where the device or stop is multi-jointed and includes excessive joints and degrees of movement or rotation. Other problems may arise where the vise stop effectively limits access of the machine tool or the cutting tool to various surfaces of the work piece. In some instances, the configuration of the vise stop limits the ability of the cutting tool to access only the top surface of the work piece.
What is needed is a simple and effective vise stop which allows repeatability of placement of parts, particularly along the X axis, in relationship to the cutting tool and which allows the work piece to be machined on all surfaces and faces which would otherwise be exposed to the cutting tool. Additionally, the device for locating the work piece should also include the ability to position the stop in relationship to both the vice and the work piece so that it may be moved out of the way when necessary or kept in position as required.
SUMMARY OF THE INVENTION
The present invention is directed to a vise stop for positioning a workpiece in a vise, the vise stop including a crossbar having a first end, a second end and a mounting surface. The crossbar is configured for attachment to the vise and a first stop arm is pivotally connected to the crossbar first end for positioning a workpiece along an X axis. In the preferred embodiment of the invention, a second stop arm is pivotally connected to the crossbar second end.
In the preferred embodiment of the invention, a friction disc is compressively disposed between an inner face of both the first and second stop arms and the first and second ends of the crossbar. The friction disc allows the stop arm to be frictionally positionable and rotatable about its point of attachment to the crossbar end. The friction disc may be configured as a fiber washer, a spring washer or a compressible o-ring. This feature of the invention allows an operator the freedom of angularly positioning and repositioning the first and second stop arms as required without loosening the carriage bolt or other means for attaching the first and second stop arms to the crossbar.
In the preferred embodiment of the invention, the stop arms each include an adjustable stop tip. A first adjustable stop tip threadedly engages a distal end of the first stop arm, the first adjustable stop tip extending from the distal end of the first stop arm at an angle lying substantially perpendicular to a longitudinal axis of the first stop arm. Similarly, a second stop tip threadedly engages a distal end of the second stop arm, the second adjustable stop tip extending from the distal end of the second stop arm at an angle lying substantially perpendicular to a longitudinal axis of the first stop arm. Both the first and second adjustable stop tips may be locked in position by a locknut.
Other advantages will become apparent to those skilled in the art from the following detailed description read in conjunction with the appended claims attached hereto.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective representational view of a machinist's vise including a vise stop according to the present invention;
FIG. 2 is a perspective representational detail view of a machinist's vise including a vise stop according to the present invention;
FIG. 3 is an exploded perspective representational detail view of a machinist's vise including a vise stop according to the present invention;
FIG. 4 is a side representational view of a machinist's vise including a vise stop according to the present invention; and
FIG. 5 is a top representational view of a machinist's vise including a vise stop according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, vise 10 is shown including vise stop 20 . Vise 10 includes vise body 11 . Fixed jaw 12 extends generally upward from body 11 and opposes movable jaw 14 . Carriage screw 13 is rotatably secured to body 11 and movable jaw 14 is threadedly engaged along the length of carriage screw 13 . Rotatable handle 15 provides a means for advancing movable jaw 14 along the length of carriage screw 13 . Vise stop 20 is shown attached to fixed jaw 12 .
Referring to FIG. 2, vise stop 20 is shown attached to fixed jaw 12 of vise 10 by first crossbar attachment screw 25 and second crossbar attachment screw 26 . As shown, vise 10 includes vise body 11 from which fixed jaw 12 extends generally upward. Fixed jaw 12 is shown opposing movable jaw 14 . FIG. 2 shows first stop arm 27 rotatably attached at crossbar first end 22 by first stop arm attachment screw 29 . Similarly, second stop arm 28 is shown rotatably attached at crossbar second end 23 by second stop arm attachment screw 30 .
First stop arm 27 includes first adjustable stop tip 35 . First lock nut 37 provides a means for securing first adjustable stop tip 35 at a pre-selected length of adjustment. Similarly, second stop arm 28 includes second adjustable stop tip 36 . Second lock nut 38 provides a means for securing second adjustable stop tip 36 at a pre-selected length of adjustment.
FIG. 3 is an exploded perspective view of vise stop 20 . Fixed jaw 12 is shown for reference. Vise stop 20 includes crossbar 21 which is attachable to fixed jaw 12 by first crossbar attachment screw 25 and second crossbar attachment screw 26 . First crossbar attachment screw 25 projects through first crossbar screw aperture 41 for threaded engagement with first fixed jaw threaded engagement aperture 42 . Similarly, second crossbar attachment screw 26 projects through second crossbar screw aperture 43 for threaded engagement with second fixed jaw threaded engagement aperture 44 .
Crossbar 21 includes crossbar first end 22 and crossbar second end 23 . First stop arm 27 is rotatably attached at crossbar first end 22 by first stop arm attachment screw 29 and second stop arm 28 is rotatably attached at crossbar second end 23 by second stop arm attachment screw 30 . First friction disc 31 is disposed between crossbar first end 22 and an inner face of first stop arm 27 . First stop arm flat washer 33 is disposed between an outer face of first stop arm 27 and a head of first stop arm attachment screw 29 providing a bearing surface at such interface. When first stop arm attachment screw 29 is torqued to a pre-selected value, first stop arm 27 is frictionally positionable, as first friction disc 31 provides first and second bearing surfaces against which crossbar first end 22 and an inner face of first stop arm 27 may be rotationally offset against one another about first stop arm attachment screw 29 .
Similarly, second friction disc 32 is disposed between crossbar second end 23 and an inner face of second stop arm 28 . Second stop arm flat washer 34 is disposed between an outer face of second stop arm 28 and a head of second stop arm attachment screw 30 providing a bearing surface at such interface. When second stop arm attachment screw 30 is torqued to a pre-selected value, second stop arm 28 is frictionally positionable, as second friction disc 32 provides first and second bearing surfaces against which crossbar second end 23 and an inner face of second stop arm 28 may be rotationally offset against one another about second stop arm attachment screw 30 . In either case, the pre-selected torque value for first stop arm attachment screw 29 and second stop arm attachment screw 30 should be in the range of 2-50 ft/lb. and more preferably in the range of 5-25 ft/lb., and in those instances wherein stop arm attachment screw 29 and second stop arm attachment screw 30 have a nominal diameter substantially equal to 0.375″, the torque value should be in the range of 10-20 ft/lb.
First adjustable stop tip 35 is shown positioned for engagement through distal end 51 of first stop arm 27 through first stop tip threaded aperture 47 . First lock nut 37 is threadedly engageable with first adjustable stop tip 35 and provides a means for securing first adjustable stop tip 35 so that a pre-selected length of first adjustable stop tip 35 projects through distal end 51 of first stop arm 27 for indexing against a workpiece.
Similarly, second adjustable stop tip 36 is shown projecting through distal end 52 of second stop arm 28 through second stop tip threaded aperture 48 . Second lock nut 38 threadedly engages second adjustable stop tip 36 and provides a means for securing second adjustable stop tip 36 so that a pre-selected length of second adjustable stop tip 36 projects through distal end 52 of second stop arm 28 for indexing against a workpiece.
First stop arm set screw 39 projects through first set screw aperture 45 for engagement against a threaded outer diameter of first stop arm attachment screw 29 to prevent first stop arm attachment screw 29 from backing out inadvertently. Similarly, second stop arm set screw 40 projects through second set screw aperture 46 for engagement against a threaded outer diameter of second stop arm attachment screw 30 to prevent second stop arm attachment screw 30 from backing out inadvertently. First stop arm set screw 39 and second stop arm set screw 40 are preferably formed of a polymeric material such that the tip will compressively conform against the threaded outer diameter of first stop arm attachment screw 29 or second stop arm attachment screw 30 without causing damage to such threaded components.
Referring to FIGS. 4 and 5, vise 10 is shown including vise stop 20 . Vise 10 includes vise body 11 . Fixed jaw 12 extends generally upward from body 11 and opposes movable jaw 14 . Vise stop 20 is shown attached to fixed jaw 12 . Workpiece W 1 is compressively held between fixed jaw 12 and opposing movable jaw 14 . Referring to FIG. 5, carriage screw 13 is rotatably secured to body 11 and movable jaw 14 is threadedly engaged along the length of carriage screw 13 . Rotatable handle 15 provides a means for advancing movable jaw 14 along the length of carriage screw 13 .
FIG. 4 shows first stop arm 27 rotatably attached at crossbar first end 22 by first stop arm attachment screw 29 . First stop arm 27 includes first adjustable stop tip 35 , shown in FIG. 3 . First lock nut 37 provides a means for securing first adjustable stop tip 35 at a pre-selected length of adjustment. Machine tool T is shown positioned above workpiece W 1 .
Referring to FIG. 5, crossbar 21 includes crossbar first end 22 and crossbar second end 23 . First stop arm 27 is rotatably attached at crossbar first end 22 by first stop arm attachment screw 29 and second stop arm 28 is rotatably attached at crossbar second end 23 by second stop arm attachment screw 30 . First friction disc 31 is shown disposed between crossbar first end 22 and an inner face of first stop arm 27 . First stop arm flat washer 33 is disposed between an outer face of first stop arm 27 and a head of first stop arm attachment screw 29 providing a bearing surface at such interface. Similarly, second friction disc 32 is disposed between crossbar second end 23 and an inner face of second stop arm 28 . Second stop arm flat washer 34 is disposed between an outer face of second stop arm 28 and a head of second stop arm attachment screw 30 providing a bearing surface at such interface. First stop arm 27 includes first adjustable stop tip 35 . First lock nut 37 provides a means for securing first adjustable stop tip 35 at a pre-selected length of adjustment. Similarly, second stop arm 28 includes second adjustable stop tip 36 . Second lock nut 38 provides a means for securing second adjustable stop tip 36 at a pre-selected length of adjustment.
Referring to FIG. 4, workpiece W 1 is repeatably locatable along Y axis 55 by placement of workpiece W 1 between fixed jaw face 16 which provides a Y axis reference surface and movable jaw face 17 . Similarly, workpiece W 1 is repeatably locatable along Z axis 57 by placement of workpiece W 1 against upper surface 18 of vise body 11 which provides a Z axis reference surface.
FIG. 5 shows workpiece W 1 and workpiece W 2 compressively held between fixed jaw 12 and opposing movable jaw 14 . Workpiece W 1 is repeatably locatable along X axis 56 by positioning workpiece W 1 against first adjustable stop tip 35 . Similarly, workpiece W 2 is repeatably locatable along X axis 56 by positioning workpiece W 2 against second adjustable stop tip 36 .
While this invention has been described with reference to the described embodiments, this is not meant to be construed in a limiting sense. Various modifications to the described embodiments, as well as additional embodiments of the invention, will be apparent to persons skilled in the art upon reference to this description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention. | A vise stop for positioning a workpiece in a vise includes a crossbar having a first end, a second end and a mounting surface. The crossbar is attachable to the vise and a first stop arm is pivotally connected to the crossbar first end for positioning a workpiece along an X axis. In the preferred embodiment of the invention, a second stop arm is pivotally connected to the crossbar second end. A friction disc is compressively disposed between an inner face of both the first and second stop arms and the first and second ends of the crossbar. The friction disc allows the stop arm to be frictionally positionable and rotatable about its point of attachment to the crossbar end. The friction disc may be configured as a fiber washer, a spring washer or a compressible o-ring. | 1 |
[0001] This is a complete application claiming benefit of provisional application Ser. No. 60/473,467 filed May 28, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to protective bumper systems, and relates more particularly to strip assemblies for protecting surfaces such as walls, display cases, furniture, and the like, from damage caused by inadvertent impact.
[0004] 2. Discussion of the Prior Art
[0005] Wall surfaces in hallways, particularly in heavily trafficked areas such as hospital corridors, airport walkways and the like, are commonly exposed to impact damage resulting from misguided carts, gurneys, people movers and the like. Likewise, grocery island cases, freezer chests, merchandise display cases, and other such items found in supermarkets, pharmacies, and department and specialty stores are often damaged in a similar manner.
[0006] To minimize such damage, bumper guards or strip assemblies of various designs have been proposed for surface mounting as chair rails, or to otherwise absorb impacts on flat walls or about corners of such structures. Protective devices of this nature must not only be functionally effective to absorb repeated impacts from different directions, but they must be simple and inexpensive to manufacture and utilize, and aesthetically pleasing, as well.
[0007] Bumper guards and the like commercially available heretofore tend to compromise one or more of the foregoing criteria. For example, in order to improve impact resistance, some products are unduly complex, making them relatively expensive to manufacture. To minimize manufacturing costs, other products may not provide adequate protection to the surfaces on which they are mounted, or may tend to deteriorate quickly in use. Finally, some such strip assemblies fail to hide the mounting hardware or otherwise present an unsightly appearance which is commercially undesirable.
SUMMARY OF THE INVENTION
[0008] It is a primary object of this invention to provide several embodiments of bumper assemblies, each of which include a base member to be attached to a surface to be protected with a top or bumper which is easily and securely affixed to the base without the need for tools to reduce installation time while providing a functionally effective, active locking, assembly where the bumper element will not be easily disengaged from the base regardless of the angle of impact against the arched surface of the bumper.
[0009] Another object of this invention is to provide an impact deflection system which includes mechanical and frictional anti-slip and anti-shrink properties to preclude or significantly reduce inadvertent lateral movement between the bumper and the base in use even after repeated impacts.
[0010] A further object of this invention is the provision of a protective strip assembly with a vinyl top or bumper element which, in some embodiments, is “rigid”, providing high impact strength in an inexpensive manner and, in other embodiments, is “flexible”, providing superior radius capability while maintaining its geometry to insure maximum protection where it is needed most. Extended lengths of such bumpers can be flexed to permit access to the underside so that the screws or the like securing the base to the surface to be protected can be hidden in the final assembly.
[0011] Still another object of this invention is to provide a bumper construction which, in addition, to the interengageable locking base and bumper elements, is designed to interact with a full range of injection molded flexible vinyl caps and corners to enable the bumper assembly to be used in a straight run or continuously around corners of a square or rectangular unit, or even a hexagonal, or other shaped unit.
[0012] Yet another object of this invention is the provision of a bumper construction of the type described wherein the bumper elements can be extruded from relatively rigid plastics materials or co-extruded from relatively rigid and relatively flexible plastics materials and the bases can be pre-slotted and extruded aluminum or plastics materials for straight runs or radius application, producing an assembly of parts which is simple and inexpensive to manufacture, install and use, offers high shatter resistance with a professional finish in a variety of colors to produce a highly attractive appearance in the final product.
[0013] It is to be understood that the instant inventive concepts are not limited by size or materials although, to facilitate a better understanding of the invention, illustrative embodiments of 1″ and 2″ bumper construction elements are illustrated and preferred materials for each of the elements are disclosed.
[0014] Upon further study of the specification, additional objects and advantages of this invention will become apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] These and other objects, features and many of the attendant advantages of this invention will be better understood by those with ordinary skill in the art in connection with the following detailed description of the preferred embodiments and the accompanying drawings wherein:
[0016] FIG. 1 is a fragmentary perspective view of a 1″ base element according to the instant inventive concepts;
[0017] FIG. 1A is an end elevational view of the base element of FIG. 1 with a frictional coating such as thermoplastic polyurethane (TPU) schematically shown on the bulbous projections to minimize movement of the bumper relative to the base even after repeated impact from different directions;
[0018] FIG. 2 is a fragmentary perspective view of a 1″ top or bumper element formed of relatively “rigid” plastics material such as polyvinyl chloride (PVC);
[0019] FIG. 3 is an end view of the assembly of the bumper element of FIG. 2 with the base element of FIG. 1 ;
[0020] FIG. 4 is an end elevational view of a 1″ bumper element including a relatively “flexible” PVC or the like arch co-extruded with a relatively “rigid” PVC or the like bridge according to the instant inventive concepts;
[0021] FIG. 5 is an end elevational view of the assembly of the bumper element of FIG. 4 with the base element of FIG. 1 ;
[0022] FIG. 6 is an end elevational view of a 2″ base element according to the instant inventive concepts;
[0023] FIG. 6A is a view similar to FIG. 1A showing the bulbous projections of the base element of FIG. 6 coated with a frictional material;
[0024] FIG. 7 is an end elevational view of a 2″ “rigid” bumper element;
[0025] FIG. 8 is an end elevational view of the assembly of the bumper element of FIG. 7 with the base element of FIG. 6 ;
[0026] FIG. 9 is a cross-sectional view through a 2″ co-extruded “flexible” bumper element according to this invention;
[0027] FIG. 10 is a cross-sectional view through the assembly of the bumper element of FIG. 9 with the base element of FIG. 6 ;
[0028] FIG. 11 is a cross-sectional view through the bumper assembly of FIG. 10 attached to a wall or fixture, the surface of which is to be protected;
[0029] FIG. 12 is an end elevational view of a 1″ “quick stop” cap for use with a bumper assembly according to this invention;
[0030] FIG. 13 is a cross-sectional view thereof taken along lines A-A of FIG. 12 ;
[0031] FIG. 14 is a top plan view of the stop cap of FIG. 12 ;
[0032] FIG. 15 is an end elevational view showing the stop cap of FIGS. 12-14 engaged with a bumper assembly as shown in FIG. 3 ;
[0033] FIGS. 16-19 are views of a 2″ “quick stop” cap similar to the views of the 1″ quick stop cap illustrated in FIGS. 12-15 ;
[0034] FIG. 20 is an end elevational view of a 1″ “snap-on” cap for % use with a bumper assembly according to this invention;
[0035] FIG. 21 is a cross-sectional view thereof taken along lines A-A of FIG. 20 ;
[0036] FIG. 22 is an enlarged detail of the female connector of the bumper element shown within the dotted circle in FIG. 20 ;
[0037] FIG. 23 is a top plan view of the 1″ snap-on cap of FIG. 20 ;
[0038] FIG. 24 is an end elevational view showing the snap-on cap of FIGS. 20-23 engaged with a bumper assembly such as shown in FIG. 3 ;
[0039] FIGS. 25-29 are views of a 2″ snap-on cap similar to the views of the 1″ snap-on cap illustrated in FIGS. 20-24 ;
[0040] FIG. 30 is an end elevational view of a 1″ “snap-on 90°” cap for use with a bumper assembly according to this invention;
[0041] FIG. 31 is a cross-sectional view thereof taken along lines A-A of FIG. 30 ;
[0042] FIG. 32 is an enlarged detail view of the female connector of the bumper element shown within the dotted circle in FIG. 30 ;
[0043] FIG. 33 is an end elevational view of one end of the snap-on 90° cap of FIG. 30 engaged with a bumper assembly such as shown in FIG. 3 ;
[0044] FIGS. 34-37 are views of a 2″ snap-on 90° cap similar to the views of the 1″, snap-on 90° cap shown in FIGS. 30-33 ;
[0045] FIG. 38 is an end elevational view of an illustrative 1″ “snap-on” cap of a different angle according to this invention;
[0046] FIG. 39 is a cross-sectional view thereof taken along lines A-A of FIG. 38 ;
[0047] FIG. 40 is an enlarged detail of the female connector of the bumper element shown within the dotted circle in FIG. 38 ;
[0048] FIG. 41 is an end elevational view of one end of the snap-on cap of FIG. 38 engaged with a bumper assembly such as shown in FIG. 3 ; and
[0049] FIGS. 42-45 are views of a 2″, snap-on cap similar to the views of the 1″ snap-on cap illustrated in FIGS. 38-41 .
[0050] Like reference characters refer to like parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0051] The foregoing descriptions and drawings should be considered as illustrative only of the principles of the invention. Numerous applications of the present invention will readily occur to those skilled in the art. Therefore, it is not desired to limit the invention to the preferred embodiments or the exact construction and operation of the preferred embodiments shown and described. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
[0052] Referring now to the drawings, and more particularly to FIG. 1 , a preferred form of base element according to the instant inventive concepts is designated generally by the reference numeral 50 and, although only a short portion is illustratively seen in FIG. 1 , the element 50 can be of indeterminate length depending upon its application. The base element 50 is preferably extruded, either from a “rigid” plastics material such as PVC or from aluminum, although other materials may be substituted therefor without departing from the instant inventive concepts. The term “rigid” PVC is well understood by those with ordinary skill in this art.
[0053] The base element 50 comprises a floor portion 52 , and a pair of longitudinally extending, transversely spaced, male connectors 54 , each comprising a stem portion 56 and a bulbous head 58 . Although not shown, the floor 52 can be pre-slotted or scored for passage or location of screws or the like adapted to attach the base element 50 to a wall or a fixture to be protected.
[0054] With reference now to FIG. 1A , the upper surfaces of the bulbous heads 58 of the male elements 54 may be coated with a friction-producing material 59 such as thermoplastic polyurethane (TPU) for a purpose to be described further hereinafter. If the base element 50 is formed of a plastics material such as PVC, the TPU may be co-extruded with the PVC in a well known manner.
[0055] With reference now to FIGS. 2 and 3 , one form of a top or bumper element according to this invention is shown at 70 as comprising an extruded arch 71 preferably formed of a “rigid” PVC. The lower inner longitudinal edges of the bumper element 70 are angled as seen at 72 and a pair of inwardly extending arcuate female connectors 74 , whose internal surfaces are complementary to the bulbous heads 58 of the male elements 54 on the base element 50 , are integrally extruded with the arch 71 .
[0056] In use, the base element 50 is screwed or otherwise attached as by screws 60 to a supporting surface schematically seen at 65 , and the female connectors 74 of the top or bumper element 70 are simply pressed into place on the bulbous heads 58 of the male connectors 54 to form the assembly 75 seen in FIG. 3 . Thus, once the base element and the caps or corners to be discussed below are secured to the supporting surface, no tools are necessary to complete the assembly. Moreover, the unique complementary nature of the arcuate female connectors 74 provides both inner and outer engagement with the bulbous heads 58 of the male connectors 54 to resist disengagement or damage to the bumper assembly 75 from repeated impacts, regardless of the angle of impact. Moreover, the frictional TPU coating 59 enhances the engagement of the base element 50 and the bumper element 70 to preclude “shrinkage”, that is, compression of the bumper element 70 which can result from repeated impacts causing the bumper element 70 to slide along the base element 50 causing separation at the ends of the bumper assembly 75 . If desired, the upper surfaces of the male connectors 54 or the inner surfaces of the female connectors 74 or both can be grooved or ribbed to enhance the mechanical engagement between these elements.
[0057] The manner in which the angled surfaces 72 of the bumper element 70 extend down along the outside edges 52 ′ of the base element 52 , and the hidden screws 60 attaching the base element 50 to the supporting surface 65 , allows the aesthetic value to be maintained well after installation.
[0058] Referring now to FIGS. 4 and 5 , a “flexible” 1″ bumper element 80 is shown as a co-extrusion of a more resilient plastics material such as PVC forming the arch 81 with an internal, co-extruded, more rigid, PVC bridge 82 defining the female connectors 84 for attachment to the base element 50 to form the assembly 85 as seen in FIG. 5 . In this manner, while the connection between the base element 50 and the bumper element 80 is between relatively rigid plastics materials, the more resilient material of the arch 81 provides a superior radius capability which maintains its geometry to ensure maximum protection where it is needed most. Once again, however, particularly with a coating 59 of TPU or the like on the bulbous heads 58 of the base element 50 , the assembly 85 seen in FIG. 5 resists “shrinkage” and slippage between the elements even with repeated impacts from different directions.
[0059] With reference to FIGS. 6, 6A and 7 - 10 , parts of a 2″ bumper assembly similar to the bumper assembly of FIGS. 1, 1A and 2 - 5 , are identified by the same reference characters followed by the suffix “a”. For all intents and purposes, other than the size and curvature of the parts, the elements are substantially identical with the exception that, in the rigid bumper element 70 a of FIGS. 7 and 8 , a bridge 76 a interconnects the female connectors 74 a to the arch 71 a.
[0060] For illustrative purposes, the flexible 2″ bumper element 80 a in FIGS. 8 and 9 has been cross-hatched for two different types of plastics material and the base element 50 a has been cross-hatched for metal, e.g., aluminum. However, it is to be understood that the materials of the various elements can be varied within the skill of the art. Additionally, the drawings are not to be considered to scale and, as noted above, the 1″ and 2″ bumper assemblies have been shown merely as illustrative of the variations in size and construction of the elements of the impact deflection system of this invention. FIG. 11 illustrates the manner in which a bumper assembly, in this instance, the 2″ flexible bumper assembly 85 a of FIG. 10 , is attached to a vertical supporting surface 65 .
[0061] Referring now to FIGS. 12-15 , a 1″ injection molded “quick stop” cap is designated generally by the reference numeral 90 and comprises an end or facing element 92 and a perpendicularly extending tab element 94 . Depressions 96 are formed in the rear surface 92 ′ of the end element 92 for reception of the ends of the male connectors 54 on a base element such as the element 50 of FIG. 1 . An opening 98 can be formed through the tab element 94 for reception of a screw of the like (not shown) to attach the same to a supporting surface through the floor 52 of the base element 50 .
[0062] The quick stop cap 90 may be used to cover the end or ends of a bumper assembly, particularly adjacent a flat surface such as an intersecting wall or a door frame (not shown). Following the attachment of a base element such as 50 to the supporting surface, a first quick stop cap such as 90 may be affixed at one end by drilling or otherwise attaching a screw (not shown) through the opening 98 and the floor 52 of the base element 50 to secure the stop cap 90 directly to the supporting surface. It is to be noted that the tab 94 is spaced slightly upwardly from the lower end 92 ″ of the end element 92 to permit the floor element 52 of the base element to underly the same, and the width of the tab element 94 is such as to fit between the stems 56 of the male connectors 54 .
[0063] The other ends of the male connectors 54 of bumper can then be engaged in the depressions. 0.96 of a further quick stop cap and screwed through the tab element 94 to a supporting surface. A bumper element 70 can then be seated on the base element 50 by simple pressure on the arch 71 of the bumper element 70 .
[0064] Alternatively, at the opposite end of a run, if necessary, the bumper element can be lifted slightly so that one of the other accessories to be discussed hereinbelow can be secured to the bumper assembly and the bumper element 70 pressed into position on the base element 50 adjacent thereto.
[0065] With reference now to FIGS. 16-19 , the construction and assembly of a 2″ quick stop cap 92 a are designated by the same reference characters as the 1″ quick stop cap of FIGS. 12-15 , followed by the suffix “a”.
[0066] With reference now to FIGS. 20-24 , an injection molded 1″, “snap-on” cap is identified by the reference numeral 100 which, in part, is similar to the stop cap 90 , but includes an arcuate end portion for aesthetic purposes as illustrated at 100 . The snap-on cap 100 is similar to the stop cap 90 in having a slightly raised tab element 102 with an opening 104 therethrough affixed to an element 106 , but includes a pair of integrally molded arcuate female connectors 108 to snap over the male connectors 54 of a base element such as shown at 50 and an arcuate extension 110 to provide a more aesthetic appearance where a flat end cap is not necessary.
[0067] In FIGS. 25-29 , a 2″ snap-on cap 100 a is designated by the same reference characters as the 1″ snap-on cap 100 of FIGS. 20-24 , followed by the suffix “a”.
[0068] With reference to FIGS. 30-33 , a 1″ injection molded “snap-on 90°” cap is seen at 120 and is adapted to interconnect a pair of bumper assemblies such as shown at 75 in FIG. 3 on perpendicular sides of a square or rectangular item to be protected from impact such as a grocery island, a freezer case or a merchandise display case (not shown). The 90° cap 120 is similar to the snap-on cap 100 of FIGS. 20-24 , but includes a pair of snap-on sections 122 , 122 perpendicularly connected by a 90° arcuate connecting section 124 to enable the same to pass around a corner. Each section 122 includes a tab element 125 with an aperture 128 and a pair of arcuate female connectors 130 .
[0069] In FIGS. 34-37 , a 2′ snap-on 90° cap 120 a is designated by the same reference characters as the 1″ snap-on 90 ′ cap 100 followed by the suffix “a”.
[0070] In FIGS. 38-41 and 42 - 45 , illustrative injection molded 1″ and 2″ snap-on caps are designated by the same reference characters as the 1″ 90°, illustratively shown as 135°, snap-on cap 120 followed by the suffixes “c” and “d”, respectively, These caps are substantially identical to the 90° caps, except that the arcuate connecting sections have angles other than 90° to enable bumper assemblies to be interconnected around a hexagonal or other shaped unit to be protected, rather than a square or rectangular unit. Obviously, snap-on caps of various angular orientations can be provided for unique display cases or the like.
[0071] The use and operation, as well as the attendant advantages, of the bumper assemblies and the above-described accessories will be obvious to the skilled artisan. A base element and selected end cap or corner are first screwed or otherwise connected to the surface to be protected. One end of a bumper element is then engaged against the end cap or corner and pressed against the base element over its length. The opposite end of the bumper element may be lifted sufficiently to secure another end cap or corner and the assembly is then completed.
[0072] The foregoing descriptions and drawings should be considered as illustrative only of the principles of the invention. Numerous applications of the present invention will readily occur to those skilled in the art. Therefore, it is not desired to limit the invention to the preferred embodiments or the exact construction and operation shown and described. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A protective bumper strip assembly for protecting surfaces such as walls, display cases, furniture, and the like, from damage caused by inadvertent impact. The protective bumper strip assembly comprises a base member attachable to a supporting surface to be protected and a bumper that is press-fit or snap-fit to the base member. The press-fit interconnection is formed from male and female interconnecting elements to form a mechanical connection therebetween. The male and female interconnecting elements include a high friction material to prevent slippage therebetween when the bumper is impacted. The interengagement between the base member and the bumper requires no additional interconnecting or attachment members. The base member includes a pair of elongated arcuate male members which receive arcuate complementary female interconnecting elements extending from the bumper. Free end portions of the assembly may include cap elements of flat or spherical shape to enclose the ends of the strip assemblies. | 4 |
DESCRIPTION
[0001] The present invention relates to a method for producing one-component sealing- and coating compounds with a polyurethane base.
[0002] Well known and precisely examined are binding agents for sealing- and coating compounds which contain isocyanate-prepolymers which can be produced by reaction of isocyanates with molecules with active hydrogen atoms like amines and alcohols and cure under the influence of humidity. DE-A 1 520 139 for example describes a procedure to produce moisture curing mixtures of polyisocyanates and polyketimines or polyaldimines, using isocyanate-prepolymers as polyisocyanate component. DE-A 2 018 233 describes moisture-curable preparations from isocyanate groups containing binding agents and polyoxazolidines.
[0003] EP-A 0 702 039 describes a procedure to produce isocyanate-prepolymers by reaction of aromatic or cycloaliphatic diisocyanates with a polyol component providing that there is a rest-content of monomeric diisocyanates of less than 0.5 weight % contained in the isocyanateprepolymers. When cycloaliphatic diisocyanates are used, the excessive diisocyanate has to be removed after the reaction has been finished by thin-layer destillation until the desirable rest content of less than 0.5 weight % is reached. Furthermore it is known from EP-A 0 702 039 and from DE-A 1 520 139 to add filling material and H 2 O-reactive hardener to the mentioned isocyanate-prepolymer with low rest content of monomeric diisocyanates in order to produce sealing- and coating material. To guarantee constancy of quality and storage stability of sealing- and coating material on the basis of already described prepolymers only a low content of water is allowed to exist. This way for example, a reaction of moisture which is introduced by the filling material with free isocyanate groups under cleavage of CO 2 can lead to a dangerous increase of pressure within the bucket. Apart from that, we see that—in the presence of hydrolysis-sensitive, latent amine curing agents for example of the type of oxazolidines, ketimines or aldimines—the lowest degree of rest moisture by reaction with the curing agent leads to a thickening or curing of the material in the bucket. After a certain degree of viscosity of more than 8000 mPas is reached, the material is no more brushable or otherwise applicable. That is why in practise expensive drying techniques like for example dehydrating agents or a very costly physical predrying are applied.
[0004] Based on this, the invention had for its purpose to provide a manufacturing process of sealing- and coating compounds so that an improved storage stability plus a simultaneous reduction of processing costs can be attained.
[0005] The following steps show how the problem is solved according to the invention by some in-situ process:
[0006] stirring a mixture containing a polyol component and a diisocyanate component so that an isocyanate-prepolymer with a rest of monomeric diisocyanate of >2 weight % is obtained intermediary.
[0007] dispersing of pigments and anorganic filling material and adding of solvent while stirring, so that the rest of the monomer diisocyanate reacts with the moisture that is introduced by the filling material and a H 2 O-content of <0.01 weight % is obtained in the reaction mixture.
[0008] adding a H 2 O-reactive latent curing agent and at least one catalyst, if necessary, and air-proof filling of the resulting sealing- and coating compound.
[0009] Advantages of the invention can be recognized in the sub claims.
[0010] The invention will subsequently be explained in detail by one illustration and some performing examples.
[0011] [0011]FIG. 1 shows the viscosity course of an one component polyurethane coating compound according to the invention (lower curve) and of a coating compound according to the technology standard (upper curve).
[0012] In the process according to the invention in hand concerning the production of sealing- and coating compounds, isocyanate-containing prepolymers are produced as basis binding agents in a first step of process. It is important to out door floor coatings, especially of balconies that isocyanate-containing prepolymers are saponification- and light-stable at the same time. Isocyanateprepolymers on the basis of polyetherpolyoles are saponification stable but less light-stable. On the other hand isocyanateprepolymers on the basis of polyesterpolyols, polyesterpolycarbonatepolyols and polyhydroxyacrylates are light-stable but can't be brought into direct contact with concrete floor surface because of their bad saponification stability. Beyond this, these polyoles have a very high grade of viscosity which requires the use of large quantities of solvents. But the application of large amounts of solvents is to the detriment of the ecological standpoint. By mixture of polyestercarbonatediols or polyhydroxyacrylates with polyether, binding materials are obtained that show a low viscosity and the curing of these binders with cycloaliphatic diisocyanates and maybe latent amine hardeners build up blockcopolymers that show a very high saponification- and light stability. In the process according to the invention a mixture of polyalkyleneetherpolyol and polyesterpolycarbonatediol are preferably used as a polyol component. Mixtures of a polyalkyleneetherpolyol and a polyester-polyetherpolyol (Fatty acis ester) or a polyhydroxyacrylate can be used as well.
[0013] Polyalkyleneetherpolyoles of the molecular weight of approx. 1000 until approx. 6000 g/mol are used preferably. Special preference is given to a polypropyleneglycol, difunctional, of an average molecular weight of 2000 g/mol or to a polypropyleneglycol, trifunctional, with an average molecular weight of 4000 g/mol. According to the invention a polyestercarbonate of an average molecular weight of approx. 1500 g/mol to approx. 2500 g/mol, preferably of 2000 g/mol, is used as a further component of the polyol mixture in the process. The polyesterpolycarbonatediols, for example, present polycarbonates of the 6-hydroxyhexaneacid-6-hydroxyhexylester.
[0014] According to the invention the process uses preferably cycloaliphatic diisocyanates as an initial compound for the isocyanateprepolymer. Cycloaliphatic diisocyanates are called those that show at least one cycloaliphatic ring per molecule and have at least one of both isocyanategroups directly attached with a cycloaliphatic ring. Appropiate as such are for example cycloaliphatic diisocyanates like 1-isocyanato-3,3,5-trimethyl-5-isocyanato-methylcyclohexane (Isophoronediisocyanate IPDI).
[0015] The used diisocyanates show varying reactive isocyanategroups within the molecule. 1-Isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (Isophoronediisocyanate IPDI) for example has one primary and one secondary isocyanategroup that are significantly different on account of their reactivity concerning the OH/NCO reaction.
[0016] In presence of the Lewis acids, like for example dibutyltindilaurate (DBTL), the reactivity of the secondary NCO group (see reaction way a)) is about one factor 10 higher than that of the primary NCO group (see reaction way b)—(N. Marscher, H. Höcker, Makromolekulare Chemie 191, 1843-1852 (1990)).
[0017] The conversion of IPDI with diols in a molar ratio of 2:1 following the above mentioned reaction scheme results in a kinetic controlled product distribution of the reaction products 1 to 2 in a ratio of approx. 9:1. As a consequence, about 10% of the monomeric diisocyanate do not react at all with polyol and at the end of the reaction are left as residual monomers. This yields in case of a reaction of a diol with an average molecular weight of about 2000 g/mol with IPDI to a residual monomeric content of IPDI of 2.5-2.8 weight %.
[0018] The production of the prepolymer takes place by stirring the polyol components and the IPDI in a vacuum-dissolver within a temperature range of 50° C. to 100° C., preferably at 90° C., until the content of the monomeric IPDI is not decreasing anymore.
[0019] In a second process step, without isolating the yielded reaction products, the pigments and the inorganic filling material of the group of heavy spar (BaSO 4 ), calcium carbonate, talcum or quartz powder, which show a water content of 0.1 to 1 weight %, in an amount up to 60 weight %—with regard to the entire weight of the components—are added also at 90° C. by being intensively stirred. Simultaneously with the pigment powder and filling material, a solvent of the group of ethylacetate, butylacetate, methylethylketone, methoxypropylacetate, toluene, xylene, or mixtures of the same in a quantity of up to 20 weight % with regard to the total weight of all components, is added. It is to be stirred at 90° C. for another 45 minutes and the excessive monomeric diisocyanate reacts with water which has been brought in by the filling materials. After cooling and adding of a hydrolysis-sensitive, latent curing agent and of at least one catalyst, the material is filled air-proof. Sealing- and coating compounds that are produced this way excell by a special low water content and from this results a high storage stability.
[0020] The hydrolysis-sensitive, latent curing agents can be chosen out of the group of oxazolidines, bisoxazolidines, ketimines or aldimines; the at least one catalyst can be chosen out of the group of p-toluenesulfonacid, dibutyltindilaurat, zinc chloride or organic acidanhydrides. A bisoxazolidine hardener is used preferably. The hardening of this system is based on a reaction of the oxazolidinerings with humidity of air by a cleavage of the oxygen bond of the oxazolidine ring. The reaction of the so formed aminealcohol with the isocyanate prepolymer follows.
[0021] [0021]FIG. 1 shows the viscosity course of a one component polyurethane coating compound for the in-situ-process according to the standard of technology (curve above) over a period of 8 weeks and a storage temperature of 40° C. It is evident from the illustration that the viscosity flux in case of the process according to the invention that is determined due to the reaction of the excessive monomeric diisocyanate with the water introduced by the filling materials and so leads to a drying of the coating compound, is significantly more favourable than the process without desiccation according to the standard of technology.
EXAMPLES
Example 1
[0022] 1200 g polypropyleneglycol, difunctional, average molecular weight 2000 g/mol, 1200 g polyesterpolycarbonatediole, average molecular weight 2000 g/mol, (Desmophen C 200, Bayer Company) and 550 g 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI), are stirred at 90° C. in a vacuumdissolver until the concentration of monomeric IPDI (approx. 2,5-2,8 weight % IPDI) does not decrease anymore (approx. 90 minutes). Subsequently 4834 g BaSO 4 , 400 g pigment powder and 1400 g xylene are added while strongly disperged at 90° C. After a stirring time of 45 minutes at 90° C. the reaction mixture is cooled down to room temperature. Then 400 g of a bisoxazolidine hardener (Härter OZ, Bayer Company), 1 g of dibutyltindilaurate and 10 g of 4-methyl-hexahydrophthalacidanhydride are added. A coating compound with the following characteristic data is obtained:
solid content: 86% viscosity at 20° C.: 2 Pas content of monomeric IPDI: 0,14% content of H 2 O: 0,005%
[0023] cured material (7 days at 23° C., 50% relative humidity):
tensile strength: 9 N/mm 2 elongation at break: 400%
[0024] Before the filling material is added the rest concentration of monomeric IPDI is 2.8% concerning the pure binding agent (30% of the total formulation) what is equivalent to a concentration of 0.0038 mol IPDI.
[0025] The water content of BaSO 4 is approx. 0.14 weight % in relation to pure BaSO 4 (48% of the total formulation) what is equivalent to a content of 0.0037 mol H 2 O.
[0026] During the stirring of 45 minutes of the reaction mixture in the presence of BaSO 4 the following desiccation reaction can be observed.
[0027] The originating amine reacts in some unspecific secondary reactions with additional NCO groups existant in the reaction mixture under formation of carbamide bindings. So approximately one can assume a stoichiometrical relation of IPDI to H 2 O of 1:1 for the desiccation reaction. This corresponds very well with the values found in practice.
[0028] Following values have been stated in the final formulation:
monomeric IPDI: 0,14 weight % => 6 × 10 −4 mol H 2 O: 0,005 weight % => 3 × 10 −4 mol
COMPARISON EXAMPLE
[0029] Into a mixture composed out of 1500 g prepolymer 1 (reaction product of a polyetherpolyol on the basis of propyleneoxide with an equivalent weight of approx. 1000 g/val with IPDI with a restmonomeric content of <0,5%, (Desmodur E 41, Bayer Company)) and 1500 g prepolymer 2 (reaction product of a polyestercarbonatediol with IPDI with a molecular weight of approx. 2000 g/mol and a restmonomeric content of 0,5% (Desmodur VPLS 2958, Bayer Company)), 4789 g BaSO 4 , 400 g pigment powder and 1400 g xylene at room temperature are added while strongly beeing disperged. 400 g of a bisoxazolidine hardener (Härter OZ, Bayer Company), 1 g dibutyltindilaurate and 10 g 4-methyl-hexahydrophthalacidanhydride are added.
[0030] A coating compound with the following characteristic data is obtained:
solid content: 86% viscosity at 20° C.: 2 Pas content of monomeric IPDI: <0,12% content of H 2 O: 0,07%
[0031] cured material (7 days at 23° C., 50% relative humidity):
tensile strength: 9 N/mm 2 elongation at break: 400%
Example 2
[0032] 1000 g polypropyleneglycol, trifunctional, average molecular weight 4000 g/mol, 1000 g of a solution of a polyhydroxyacrylate, approx. trifunctional, average molecular weight Mn=1300 g/mol, (Joncryl SCX-507, Jonson Polymer Company) in butylacetate with an OH content of 4.2% related to the solid matter and 650 g 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI) are stirred at 90° C. in a vacuumdissolver until the content of monomeric IPDI (approx. 2.6 weight % IPDI) does not decrease anymore (approx. 90 minutes). Then, while being strongly disperged at 90° C., 5139 g BaSO 4 , 400 g pigment powder and 1400 g xylene are added. After a stirring time of 45 minutes at 90° C. the reaction mixture is cooled down to room temperature and 400 g of a bisoxazolidine hardener (Härter OZ, Bayer Company), 1 g of dibutyltindilaurate and 10 g of 4-methyl-hexahydrophthalacidanhydride are added.
[0033] A coating compound with the following characteristic data is obtained:
solid content: 84% viscosity at 20° C.: 3 Pas content of monomeric IPDI: 0,18% content of H 2 O: 0,005%
[0034] cured material (7 days at 23° C., 50% relative humidity):
tensile strength: 10 N/mm 2 elongation at break: 80%
Example 3
[0035] 1500 g polypropyleneglycol, trifunctional, average molecular weight 4000 g/mol, 528 g of a fatty acid ester, approx. trifunctional, average molecular weight 561 g/mol, (Sovermol 750, Henkel Company) with an OH content of 9.1 % related to the solid matter and 810 g 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI) are stirred at 90° C. in a vacuumdissolver until the content of monomeric IPDI (approx. 2.8 weight % IPDI) does not decrease anymore (approx. 90 minutes). Subsequently 5039 g BaSO 4 , 400 g pigment powder and 1312 g xylene are added while being strongly disperged at 90° C. After a stirring time of 45 minutes at 90° C. the reaction mixture is cooled down to room temperature. Then 400 g of a bisoxazolidine hardener (Härter OZ, Bayer Company), 1 g of dibutyltindilaurate and 10 g of 4-methyl-hexahydrophthalacidanhydride are added.
[0036] A coating compound with the following characteristic data is obtained:
solid content: 86% viscosity at 20° C.: 2 Pas content of monomeric IPDI: 0,18% content of H 2 O: 0,005%
[0037] cured material (7 days at 23° C., 50% relative humidity):
tensile strength: 12 N/mm 2 elongation at break: 50%
[0038] The formulations of the coating compounds from the examples 1,2 and 3 contain:
[0039] 28-34 weight % prepolymer
[0040] 52-56 weight % filling material/pigments
[0041] 14-16 weight % solvents
[0042] 4 weight % latent hardener.
[0043] The sealing- and coating compounds that are produced according to the method according to the invention show a very high storage stability of at least one year. | The invention relates to a method for producing one-component sealing and coating compounds with a polyurethane base The inventive method provides a simpler means of production as well as guaranteeing improved storage stability of the compounds produced, and comprises the following steps: agitating a mixture of polyol components and one diisocyanate component to obtain an isocyanate prepolymer with a residual content of monomeric diisocyanate of 2 wt per ct; dispersing pigments and inorganic fillers in the mixture and adding a solvent whilst agitating, the residual content of monomeric diisocyanate reacting with the moisture provided by the fillers so as to obtain an H 2 O content of <0.01 wt per ct in the reaction mixture; adding an H 2 O-reactive latent hardener and optionally, at least one catalyst, and airtight packing of the resulting sealing and coating compound. | 2 |
This application is a division of application Ser. No. 07/462,525 filed Jan. 9, 1990, now U.S. Pat. No. 5,060,043.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor wafer and, more specifically, to an improvement of a mark for identifying crystal orientation of a semiconductor wafer provided on the semiconductor wafer for identifying a specific crystal orientation of the semiconductor wafer.
2. Description of the Background Art
An orientation flat serving as a reference for identifying the crystal orientation is provided on a semiconductor wafer. FIG. 6 is a plan view of a semiconductor wafer having the orientation flat. The orientation of a main surface 2 of the semiconductor wafer 1 is (100). One crystal orientation <110> of the semiconductor wafer 1 is in the direction shown by A and in the direction shown by B which is orthogonally intersecting the direction shown by A. An orientation flat 3 is provided on the semiconductor wafer 1 by cutting a portion of an outer periphery of the semiconductor wafer 1 along the direction shown by A. The orientation flat 3 has the following two functions.
First, the orientation flat 3 serves as a reference for alignment in lithography during the manufacturing process of the semiconductor.
Secondly, the orientation flat 3 serves as a reference in dicing the semiconductor wafer into semiconductor chips.
However, provision of the orientation flat on the semiconductor wafer exhibits the following drawbacks. As described above, the orientation flat serves as a reference for alignment. In order to realize precise alignment, the orientation flat must be of some length. Consequently, a large area of the semiconductor wafer is cut away in providing the orientation flat on the semiconductor wafer. Accordingly, the number of semiconductor chips which can be formed on one semiconductor wafer is reduced.
As the orientation flat is provided on the semiconductor wafer, the peripheral portion of the semiconductor wafer comes to be defined by a curve and a line. When the semiconductor wafer having the orientation flat is thermally processed, the outer peripheral portion of the semiconductor wafer does not expand uniformly, thereby causing stress in the semiconductor wafer. Now, when a force is applied to a member having a portion at which the shape of the member is abruptly changed, the stress is concentrated at that portion. As to the semiconductor wafer having the orientation flat, the shape of the semiconductor wafer is abruptly changed at the portion of the orientation flat. Therefore, when the semiconductor wafer is thermally processed, stress is concentrated on the portion having the orientation flat. Consequently, crystal defects are generated at the portion of the orientation flat of the semiconductor wafer. The crystal defects can be seen as slip lines.
FIG. 7 is a plan view of a semiconductor wafer on which slip lines are generated. The orientation of a main surface 5 of a semiconductor wafer 4 is (100). One crystal orientation <110> of the semiconductor wafer 4 is in the direction shown by C and in the direction shown by D which is orthogonal to the direction shown by C. The orientation flat 6 is formed by cutting away a portion of the outer periphery of the semiconductor wafer 4 along the direction of C. Slip lines 7 are generated at the portion of the orientation flat 6 of the semiconductor wafer 4. The slip lines 7 extend in the direction of D. The portion which is discontinued from the curve defining the outer periphery of the semiconductor wafer 4, that is, the portion of the orientation flat 6, must be long to some extent as mentioned above. Therefore, stress is concentrated at a relatively wide range during thermal processing of the semiconductor wafer 4, so that the slip lines 7 are generated in the wide range.
The following two prior art references disclose semiconductor wafers having marks, other than the orientation flat, for identifying the crystal orientation. One is disclosed in Japanese Patent Laying-Open No. 60-119709. In this prior art, a through hole, a semicircular notch or the like is provided on the semiconductor wafer, which is used as a mark for identifying the crystal orientation of the semiconductor wafer.
The specific content will be described in the following. Japanese Patent Laying-Open No. 60-119709 discloses three semiconductor wafers. The first one shown in FIG. 8 has a through hole 9 serving as a mark for identifying the crystal orientation at the center of the semiconductor wafer 8 whose outer periphery is circular. The through hole 9 is an isosceles triangle. A portion at which two sides having the same length intersect with each other is a vertex 10 of the isosceles triangle. A side 11 is facing the vertex 10. A line coupling the side 11 with the vertex 10 seems to identify the crystal orientation of the semiconductor wafer 8.
In the semiconductor wafer 8 shown in FIG. 8, the area of the through hole 9 is made smaller than the area of the wafer which is cut off for providing the orientation flat. Therefore, the consequential loss of the semiconductor wafer 8 can be made smaller than that of the semiconductor wafer having the orientation flat. However, since the distance between the vertex 10 and the side 11 is short, the through hole 9 does not exactly indicate the crystal orientation.
Since the outer periphery of the semiconductor wafer 8 is circular, the outer periphery of the semiconductor wafer 8 expands uniformly when it is thermally processed. Consequently, no stress is generated in the semiconductor wafer 8, and accordingly no slip line is generated in the semiconductor wafer 8.
Another semiconductor wafer disclosed in the Japanese Patent Laying-Open No. 60-119709 is as shown in FIG. 9, which has a through hole and a notch serving as marks for identifying the crystal orientation provided on a semiconductor wafer having circular outer periphery. A circular through hole 13 is provided at the center of the semiconductor wafer 12. A semicircular notch 14 is provided on the outer periphery of the semiconductor wafer 12. A line coupling the through hole 13 and the notch 14 seems to indicate a specific crystal orientation of the semiconductor wafer 12. The loss of the semiconductor wafer 12 is only the areas at both ends of the line, namely, the portion of the through hole 13 and the notch 14. The through hole 13 and the notch 14 may be small, since they are used only for defining a line serving as a reference for identifying crystal orientation. Compared with the orientation flat, the area loss of the semiconductor wafer can be reduced by these marks for identifying the crystal orientation.
As mentioned above, the notch 14 may be small. Therefore, the outer periphery of the semiconductor wafer 12 is approximately circular, so that the outer portions of the semiconductor wafer 12 are expanded approximately uniformly when it is thermally processed. Accordingly, the stress generated in the semiconductor wafer 12 is small, and therefore slip lines are less frequently generated even if the stress is concentrated at the notch 14.
A further semiconductor wafer disclosed in the Japanese Patent Laying-Open No. 60-119709 is as shown in FIG. 10, which has through holes serving as marks for identifying crystal orientation provided on a semiconductor wafer 15 whose outer periphery is circular. Through holes 16 and 17 are provided near the outer periphery of the semiconductor wafer 15, which through holes 16 and 17 are both circular. A line coupling the through holes 16 and 17 seems to identify the crystal orientation of the semiconductor wafer 15. The area loss of the semiconductor wafer 15 can be reduced for the same reason as described above with reference to the semiconductor wafer 12 shown in FIG. 9. Slip lines are not generated in the semiconductor wafer 15 from the same reason as described above with reference to the semiconductor wafer 8 shown in FIG. 8.
Another example of prior art relating to a semiconductor wafer, having a mark other than an orientation flat for identifying the crystal orientation, is disclosed in Japanese Patent Laying-Open No. 63-148614. In the prior art, a mark for identifying the crystal orientation is provided on a semiconductor wafer in the following manner. First, a main surface of a semiconductor wafer having circular outer periphery is irradiated from above by X-ray. The diffracted X-ray is measured by a detector, whereby the crystal orientation of the semiconductor wafer is detected. A mark indicating the crystal orientation is applied on the surface of the semiconductor wafer. Since a mark indicating the crystal orientation is applied on the surface of the semiconductor wafer, there is no area loss of the semiconductor wafer. The outer periphery of the semiconductor wafer is circular, so that the outer periphery of the semiconductor wafer expands uniformly when it is thermally processed. Therefore, no stress is generated in the semiconductor wafer, and accordingly no slip line is generated in the semiconductor wafer.
Semiconductor wafers are manufactured by slicing a bar semiconductor. Since the bar is considerably long, it is difficult to provide a through hole in the longitudinal direction of the bar. Therefore, in the prior art disclosed in the Japanese Patent Laying-Open No. 60-119709 in which a through hole is provided on a semiconductor wafer as a mark for identifying the crystal orientation, the through hole must be provided on the semiconductor wafer after it is sliced. Provision of a through hole in a number of the semiconductor wafer one by one takes much time, reducing efficiency in the producing of semiconductor devices.
As to the prior art examples disclosed in the Japanese Patent Laying-Open No. 60-119709, the mark for identifying the crystal orientation shown in FIG. 8 does not precisely indicate the crystal orientation of the semiconductor wafer, compared with the orientation flat. The following is also a reason of the lower precision in indicating the crystal orientation of this mark for identifying the crystal orientation. Namely, the mark for identifying the crystal orientation shown in FIG. 8 indicates a specific crystal orientation by a line coupling the side 11 and the vertex 10. However, there are two lines coupling the side 11 and the vertex 10. Consequently, the crystal orientation cannot be uniquely indicated by the mark for identifying the crystal orientation. It is the same in the case of the mark for identifying the crystal orientation shown in FIG. 9. Namely, there can be a number of lines coupling the circular through hole 13 and the semicircular notch 14 because of their finite size, so that the crystal orientation cannot be precisely indicated. It is also the same in the case circular marks of finite size, as shown in FIG. 10.
The prior art disclosed in the Japanese Patent Laying-Open No. 63-148614 provides a mark indicating the crystal orientation on the surface of the semiconductor wafer, as described above. Since such a mark cannot not be applied on the bar member before slicing, the mark must be applied on individual semiconductor wafers produced by slicing the bar. Namely, in this prior art also, marks must be applied on the semiconductor wafer one by one, reducing the efficiency in producing semiconductor devices.
In addition, specific disclosure is not given in the Japanese Patent Laying-Open No. 63-148614 about the mark for identifying the crystal orientation applied on the semiconductor wafer. Whether or not the crystal orientation can be precisely indicated by the mark cannot be determined.
SUMMARY OF THE INVENTION
The present invention was made to solve the above described problems and its object is to provide a semiconductor wafer having a mark for identifying specified crystal orientation which mark can be readily provided to the bar member before slicing, which reduces area loss of the semiconductor wafer and suppresses generation of slip lines.
Another object of the present invention is to provide a semiconductor wafer having a mark which precisely identifies the crystal orientation of the semiconductor wafer.
A further object of the present invention is to provide a method of effectively providing marks for identifying specified crystal orientation of the semiconductor wafer on the semiconductor wafers.
The present invention relates to a semiconductor wafer having a mark for identifying a specified crystal orientation. The semiconductor wafer in accordance with the present invention has a circular outer periphery.
In accordance with a first aspect of the present invention, first and second angular notches, each defined by a pair of intersecting surfaces are provided spaced apart from each other on the outer periphery of the semiconductor wafer. A line coupling the vertices of the first and second notches serves as a reference for identifying a specified crystal orientation.
In accordance with a second aspect of the present invention, a notch serving as a mark for identifying the crystal orientation is provided on the outer periphery of the semiconductor wafer. The notch has its shape defined by two orthogonally intersecting notched surfaces.
In accordance with the first aspect of the present invention, first and second notches are provided spaced apart from each other on the outer periphery of the semiconductor wafer. A line coupling the first and second notches serves as a reference for identifying a specified crystal orientation. The area loss of the semiconductor wafer is only the portions on both ends of the line, namely, the portions of the notches. The notches may be small, since they are only to define a line serving as a reference for identifying the crystal orientation. Therefore, in accordance with the first aspect of the present invention, the area loss of the semiconductor wafer can be reduced compared with that of the semiconductor wafer having an orientation flat.
As described in the foregoing, the notch may be small. Therefore, the outer periphery of the semiconductor wafer is nearly circular. Consequently, the outer periphery of the semiconductor wafer expands approximately uniformly when it is thermally processed, so that the stress generated in the semiconductor wafer is small. Accordingly, slip lines are less frequently generated even if the stress is concentrated to the notch.
In addition, since the notches are provided on the outer periphery of the semiconductor wafer, they can be provided on the bar member before slicing. By using the notch as the mark for identifying the crystal orientation, the efficiency in producing semiconductor devices can be improved as compared with alternative techniques wherein through holes or a mark on the surface of the semiconductor wafer are used as marks for identifying the crystal orientation.
In accordance with the second aspect of the present invention, a notch serving as a mark for identifying the crystal orientation is provided on the outer periphery of the semiconductor wafer. The notch has its shape defined by two notched surfaces orthogonally intersecting with each other. Line formed by the intersection of the two notched surfaces defining the notch and the main surface of the semiconductor wafer serves as references for identifying the specified crystal orientation.
In order to reduce area loss, the notch cannot be made very large. Therefore, the lines formed by the intersection of the notched surfaces and the main surface of the semiconductor wafer cannot be made very long. Consequently, the precision in alignment for lithography is lower than that of the orientation flat. However, a line (hereinafter referred to as a first reference line) formed by the intersection of one of the notched surfaces and the main surface of the semiconductor wafer encounters in the orthogonal direction a line (hereinafter referred to as a second reference line) formed by the intersection of the other one of the notched surfaces and the main surface of the semiconductor wafer. Therefore, it is convenient in dicing the semiconductor wafer into chips. More specifically, the dicing can be carried out in the following manner. A number of cut lines are provided on the surface of the semiconductor wafer parallel to each other, referring to the first reference line. Thereafter, a number of cut lines are provided parallel to each other on the surface of the semiconductor wafer referring to the second reference line. The semiconductor wafer is separated into chips by applying a bending stress thereto.
As described above, the notch is not very large. Therefore, slip lines are less frequently generated at the notch during thermal processing of the semiconductor wafer, as in the first aspect of the present invention.
Since the mark for identifying the crystal orientation is a notch, it can be provided easily on the bar member before slicing. Therefore, compared with the cases where through holes and marks provided on the surface of the semiconductor wafers are used as the marks for identifying crystal orientation, the efficiency in producing semiconductor devices can be improved. Especially in the second aspect of the present invention, only one notch is provided on the semiconductor wafer, so that the efficiency in producing semiconductor devices can be further improved compared with the first aspect of the present invention.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a first embodiment of the semiconductor wafer in accordance with the present invention;
FIG. 2 is a plan view of a second embodiment of the semiconductor wafer in accordance with the present invention;
FIG. 3 is a plan view of a third embodiment of the semiconductor wafer in accordance with the present invention;
FIG. 4 is a plan view of a fourth embodiment of the semiconductor wafer in accordance with the present invention;
FIGS. 5A to 5D show, in this order, a method of manufacturing the semiconductor wafer in accordance with the present invention;
FIG. 6 is a plan view of a conventional semiconductor wafer having an orientation flat serving as a mark for identifying crystal orientation;
FIG. 7 shows slip lines generated on the portion of the orientation flat; and
FIGS. 8 to 10 are plan views of conventional semiconductor wafers having through holes and the like serving as marks for identifying crystal orientation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the semiconductor wafer in accordance with the present invention will be described with reference to FIG. 1. An outer periphery of a semiconductor wafer 21 is circular. The diameter of the circle is, for example 200 mm. The semiconductor wafer 21 is formed of silicon, with the orientation of the main surface 22 being (100). First and second notches 23 and 24 are provided on the outer periphery of the semiconductor wafer 21. The first and the second notches 23 and 24 are both V shaped. The vertex of the V shape of the first notch 23 is 25. The vertex of the V shape of the second notch 24 is 26. A line 27 coupling the vertices 25 and 26 is on the diameter of the circle defining the outer periphery of the semiconductor wafer 21. Therefore, the line 27 coupling the vertices 25 and 26 has approximately the same length as the diameter of the circle defining then outer periphery of the semiconductor wafer 21. The line 27 coupling the vertices 25 and 26 indicates one crystal orientation <110> of the semiconductor wafer 21, represented by E. The line 27 is an imaginary line. The line 27 is not directly drawn on the semiconductor wafer 21. How to form the first and the second notches 23 and 24 serving as marks for identifying the orientation <110> on the semiconductor wafer 21 will be described in the following with reference to FIGS. 5A to 5D.
First, referring to FIG. 5A, a single crystal silicon bar 27 is prepared. The single crystal silicon bar 27 has its outer surface polished.
Thereafter, referring to FIG. 5B, the single crystal silicon bar 271 is irradiated by X-ray, and the crystal orientation <110> is detected by the X-ray diffraction. The first notch 23 and the second notch 24 are provided on the outer periphery of the single crystal silicon bar 271 such that the line coupling the vertex 25 of the first notch 23 and the vertex 26 of the second notch 24 indicates the crystal orientation <110>. The first and second notches 23 and 24 are provided along a generating line of the single crystal silicon bar. The second notch 24 is not shown in FIG. 5B.
Thereafter, referring to FIG. 5C, both ends of the single crystal silicon bar 271 are cut. The surface 22 having the orientation of (100) is exposed.
Then, referring to FIG. 5D, the single crystal silicon bar 271 is sliced to provide semiconductor wafers 21. By the above described process, a semiconductor wafer 21 having first and second notches 23 and 24 serving as marks for identifying the crystal orientation <110> is manufactured.
Particular effects of this embodiment will be described in the following. As shown in FIG. 1, the first and second notches 23 and 24 are V shaped, so that the vertices 25 and 26 are defined unequivocally. Accordingly, the line 27 coupling the bottom portions 25 and 26 indicating the crystal orientation of the semiconductor wafer 21 is defined uniquely. Consequently, in accordance with this embodiment, the crystal orientation of the semiconductor wafer 21 can be indicated exactly.
In this embodiment, the line 27 coupling the vertices 25 and 26 indicates the specified crystal orientation of the semiconductor wafer 21. Compared with a case in which notches are provided such that a line coupling the both bottom portions intersect, by a predetermined angle, with the specified crystal orientation of the semiconductor wafer, alignment in lithography is facilitated.
The line 27 coupling the vertices 25 and 26 has approximately the same length as the diameter of the circle defining the outer periphery of the semiconductor wafer 21 in this embodiment. It is longer than a common orientation flat. Therefore, alignment for lithography can be carried out more precisely.
When a semiconductor wafer having an orientation flat is thermally processed, the semiconductor wafer may possibly be warped, since the outer periphery of the semiconductor wafer does not expand uniformly. The warp of the wafer cannot be neglected when the diameter of the circle defining the outer periphery of the semiconductor wafer is 200 mm or larger. However, in the present embodiment, the outer periphery of the semiconductor wafer is approximately circular, so that the outer periphery of the wafer expands uniformly during thermal processing. Therefore, even when the diameter of the circle defining the outer periphery of the semiconductor wafer is large, the problem of the warp is not very serious.
Although the first and the second notches 23 and 24 are provided such that the line 27 coupling the vertices 25 and 26 approximately corresponds to a diameter of the circle defining the outer periphery of the semiconductor wafer 21 in the foregoing, locations for the notches are not limited thereto, and notches may be provided such that the line coupling the bottom portions is not on the diameter of the circle defining the outer periphery of the semiconductor wafer.
Since the first and the second notches 23 and 24 are to specify both ends of the line 27 serving as a reference for identifying the specified crystal orientation, 1 mm may be enough as the depth of the first and second notches.
A second embodiment of the semiconductor wafer in accordance with the present invention will be described in the following with reference to FIG. 2. A semiconductor wafer 31 has a circular outer periphery, and the semiconductor wafer 31 is formed of silicon with the orientation of the main surface 32 being (100) First and second notches 33 and 34 are provided on the outer periphery of the semiconductor wafer 31. The first and second notches 33 and 34 are both V shaped. The vertex of the V shape of the first notch 33 is 35. The vertex of the V shape of the second notch 34 is 36. A line coupling the vertices 35 and 36 is on the diameter of the circle defining the outer periphery of the semiconductor wafer 31. Consequently, the line 37 coupling the vertices 35 and 36 has approximately the same length as the diameter of the circle defining the outer periphery of the semiconductor wafer 31. The first and the second notches 33 and 34 are provided such that the line 37 coupling the vertices 35 and 36 intersect a crystal orientation <110> of the semiconductor wafer 31 shown by F by a prescribed angle. This is the only difference between the second embodiment and the first embodiment. The line 37 is an imaginary line and is not directly drawn on the semiconductor wafer 31.
When the notches are provided at such positions, the generation of the slip lines can be suppressed compared with the semiconductor wafer having an orientation flat, even if the stress is concentrated to the notch during thermal processing of the semiconductor wafer.
A third embodiment of the semiconductor wafer in accordance with the present invention will be described in the following with reference to FIG. 3. The semiconductor wafer 41 has a circular outer periphery. The orientation of the main surface 42 is (100). First and second notches 43 and 44 are provided on the outer periphery of the semiconductor wafer 41. The first notch 43 is defined by a notched surface 47 and a notched surface 48. The notched surfaces 47 and 48 abut each other orthogonally. The orthogonal intersecting point is the vertex 45. The second notch 44 is defined by notched surfaces 49 and 50. The notched surfaces 49 and 50 abut each other orthogonally. The orthogonal intersecting point is the vertex 46.
A line 58 coupling the vertices 45 and 46 indicates one crystal orientation <110> of the semiconductor wafer 41 shown by H. The notched surfaces 48 and 50 are on the same plane. A line formed by the intersection of the notched surfaces 48 and 50 with the main surface 42 of the semiconductor wafer 41 also indicates one crystal orientation <110> of the semiconductor wafer 41 shown by H.
The line 59 which is an extension of the line formed by the intersection of the notched surface 47 and the main surface 42 shows one crystal orientation <110> of the semiconductor wafer 41 shown by G. The line 60 which is an extension of a line formed by the intersection of the notched surface 49 with the main surface 42 also shows one crystal orientation <110> of the semiconductor wafer 41 shown by G.
A particular effects of the present embodiment will be described in the following. As shown in FIG. 6, in case of a semiconductor wafer 1 having the orientation flat 3, the identification of the crystal orientation <110> shown by B is realized by searching an orthogonal direction to the orientation flat 3. In third embodiment of the present invention, the line 58 indicates the crystal orientation <110> as shown in FIG. 3, while lines 59 and 60 indicate the crystal orientation <110> shown by G. The lines 58, 59 and 60 are imaginary lines and not actually drawn on the semiconductor wafers 41.
A fourth embodiment of the semiconductor wafer in accordance with the present invention will be described in the following. The semiconductor wafer 51 has a circular outer periphery. The semiconductor wafer 51 is formed of silicon with the orientation of the main surface 52 being (100) A notch 53 is provided on the outer periphery of the wafer 51. The notch 53 is defined by a first notched surface 54 and a second notched surface 55. The first notched surface 54 and the second notched surface 55 abut orthogonally each other. The line 56 which is an extension of a line formed by the intersection of the first notched surface 54 and the main surface 52 indicates one crystal orientation <110> of the semiconductor wafer 51 shown by I. The line 57 which is an extension of a line formed by the intersection of the second notched surface 55 and the main surface 52 indicates one crystal orientation <110> of the semiconductor wafer 51 shown by J. The lines 56 and 57 are imaginary lines and not actually drawn on the semiconductor wafer 51.
In this embodiment, the crystal orientation <110> shown by I and the crystal orientation <110> shown by J can be identified by one notch. Therefore, the semiconductor wafer 51 is diced into chips by the following method. First, a number of cut lines are provided in parallel to each other on the surface of the semiconductor wafer 51 along the line 56. Thereafter, a number of cut lines are provided in parallel to each other on the surface of the semiconductor wafer 51 along the line 57. A bending stress is applied to the semiconductor wafer 51 so that the wafer is divided into chips.
In this embodiment, the line 56 indicates the crystal orientation <110> represented by I while the line 57 indicates the crystal orientation <110> represented by J. However, the present invention is not limited to this embodiment and the notches may be provided such that the line 56 intersects the crystal orientation <110> represented by I by a prescribed angle, and the line 57 intersects the crystal orientation <110> represented by J by a prescribed angle.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | A semiconductor wafer having a mark indicating a specified crystal orientation is disclosed. In a preferred embodiment, first and second notches are provided on a circular outer periphery of the semiconductor wafer. A line coupling the vertices of the first and second notches indicates the crystal orientation of the semiconductor wafer. By using such notches as marks for identifying the crystal orientation, the loss of useful area of the semiconductor wafer can be reduced. Generation of slip lines which are crystal defects can be suppressed. Such notches can be formed on the bar member before slicing. By providing the notches on the bar member before individual wafers are cut therefrom, it becomes unnecessary to provide notches on the individual semiconductor wafers one by one. | 8 |
BACKGROUND OF INVENTION
[0001] 1. Field of Invention
[0002] This invention relates to packaging for holding and displaying frangible items such as holiday ornaments.
[0003] 2. Discussion of Related Art
[0004] Decorative items such as holiday ornaments are customarily packaged in boxes that enable the ornaments to be only partially viewed without removing them from the packaging. Typically, the packaging includes a base, tray and cover. In some prior art packaging of this type, the base and cover are made of one piece of opaque material such as cardboard. Typically, the cover has a transparent plastic window, and the ornaments are supported on a tray inside the base. In other such prior art packaging, the base and cover are separately fabricated, and the cover made of a transparent material extends over the side walls of the base so that the ornaments inside the packaging can only be viewed through the top of the cover. In both forms of prior art described, the trays are made of opaque material, and the trays are provided with recesses that receive the ornaments in a position which leaves half or more of the surface of the ornament hidden from view.
SUMMARY OF INVENTION
[0005] In accordance with one aspect of this invention, the packaging enables substantially all of each ornament in the package to be viewed through the cover as the tray which supports the ornaments is made of a transparent material and the inner surface of the base is light reflective or mirror-like. In accordance with another aspect of this invention the ornaments sit in a relatively high position above the top of the side wall of the base, and the cover enables the ornaments to be viewed through the side as well as the top of the packaging. The elevated position of the ornament and the light properties of the materials from which the various components are made allow substantially all sides of the ornaments to be viewed through the cover without opening or removing the ornaments from the packaging.
BRIEF DESCRIPTION OF DRAWINGS
[0006] The accompanying drawings, are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:
[0007] FIG. 1 is a perspective view of ornament packaging embodying the present invention;
[0008] FIG. 2 is a cross-sectional view of the packaging taken along section line 2 - 2 of FIG. 1 ;
[0009] FIG. 3 is an exploded perspective view of the base and tray of one embodiment of the packaging,
[0010] FIG. 4 is a perspective view of a partially erected base in accordance with one embodiment of this invention;
[0011] FIG. 5 is a plan view of the blank from which the base of FIG. 4 is made;
[0012] FIG. 6 is a perspective view of one embodiment of the cover in accordance with the present invention, and
[0013] FIG. 7 is a plan view of the blank from which the cover of FIG. 6 is made.
DETAILED DESCRIPTION
[0014] This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing”, “involving”, and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
[0015] The packaging of the present invention includes three major elements, namely, a base 10 , cover 12 and tray 14 . The tray has one or more recesses 16 that receive the ornaments to be displayed in the packaging. As broadly described, packaging composed of a box, cover and tray are well known in the art. However, the packaging of the present invention includes modifications of several parts that markedly enhance the display of the glass ornaments or other products placed in the packaging.
[0016] In accordance with one aspect of the present invention, the inner surfaces 17 of the base of packaging 10 are dark, and preferably black, and are light reflective, that is, they have a mirror-like quality that will reflect the ornaments or other items disposed before the surface. The base may be made of heavy paper, cardboard or other sheet product that preferably possesses enough stiffness to maintain the side walls of the box in a generally perpendicular position with respect to the base bottom wall.
[0017] In accordance with one embodiment of the invention, the base 10 is made of cardboard cut as a single sheet in the configuration shown in FIG. 5 . The base blank shown has a pair of opposite side walls 18 attached to the bottom wall 20 along fold lines 22 , and flaps 24 extend from each end thereof at fold lines 26 . On the other two opposite sides of the bottom wall 20 are additional side walls 28 attached to those sides along fold lines 30 . This second set of opposite side walls 28 are formed so as to fold up and over the flaps 24 on the first pair of side walls and extend downwardly along their inner faces, and a flange 32 is provided at the edge of each of the second pair of side walls to frictionally engage the upper surface 17 of the bottom wall 20 when the box is erected. This particular configuration of the box is free of adhesive or other material which would detract from the clean unadorned box surfaces and add to its manufacturing costs.
[0018] The tray 14 is made of transparent material such as PVC plastic and preferably is thermoformed. The tray is sized to fit within the base 10 and is complementary shaped so as to just fit within the base. The tray has side walls 36 whose lower edges 38 preferably rest on the base bottom wall 20 and flanges 32 , and the side walls are of a height to support the top wall 40 of the tray at or just below the rim 42 of the base. The wells 16 are shaped to complement the shape of the ornaments 44 or other items to be displayed in the package, and in the embodiment shown, as the ornaments are essentially round, the wells 16 are approximately hemi-spherical in shape. In the specific embodiment shown, as the wells are designed to receive decorative ornaments 44 that include a spherical body 46 and a short cylindrical collar 48 carrying the rings 50 by means of which the ornaments are hung, the wells 16 have generally semi-cylindrical extensions 52 that receive the collars. It is to be appreciated that while three wells are shown in the drawings, essentially any number may be provided, depending only on the size of the packaging and the size of the ornaments to be contained therein.
[0019] In accordance with another aspect of the present invention, the ornaments 44 extend above the rim 42 of the base 10 . The portions of the ornaments extending above the tray 14 and base 10 are, however, enclosed by the cover 12 .
[0020] In accordance with yet another aspect of the invention, the cover 12 is in the form of a sleeve (see FIG. 6 ) that fits snugly over the bottom 20 and side walls 18 and 28 of the base, but the top wall 60 of the cover is spaced substantially above the rim 42 of the base 10 and the top wall 40 of the tray 14 , so as to enclose the portions of the ornaments that extend above the tray. In accordance with one embodiment of the invention, the cover is made of a transparent material such as PVC. In the embodiment shown, the plastic from which the cover is made is formed as a sheet (see FIG. 7 ) and is provided with fold lines shown in broken lines in FIG. 7 , that define the top wall 60 and bottom walls 62 , opposite side walls 64 , and opposite end walls 66 , the latter each being composed of a pair of inner flaps 68 and a pair of outer flaps each composed of a female 70 and male 72 . The inner flaps 68 , two at each end of the cover, are integral with the side edges of the side walls 64 . The outer pair of flaps 70 and 72 are connected to the end edges 74 of the top and bottom walls 60 and 62 of the cover and in turn overlap one another and enclose the inner flaps 68 when the cover is erected. The outer flaps are releasably held in the cover forming configuration by means of tongues 76 , two carried on each of the male outer flaps 72 and threaded through a pair of slots 78 in the other outer flaps 70 . The assembly of the various end flaps is shown in FIGS. 1 and 2 . Obviously, other forms of closure may be used as well, such as single tongue and slot, interengaging slits, etc.
[0021] In accordance with the embodiment of cover shown in FIGS. 6 and 7 , the cover is erected by bending the various walls along the fold lines (shown as broken lines) that connect them to adjacent walls of the cover blank. A narrow flange 80 is provided along the edge 82 of the lower wall 62 which is cemented to the one side wall 64 so as to permanently form the cover into a sleeve when the inner and outer pairs of flaps 68 , 70 and 72 are opened. Obviously such a flange could alternatively be provided along the edge 84 of the side wall 64 . In the configuration of an open ended sleeve, the sub-assembly of base 10 , tray 14 and ornaments 44 may be slipped within the cover through either end, and when the ends of the sub-assembly are aligned with the end edges of the top and bottom walls, the inner and outer end flaps may be detachably locked in the manner described. It will be appreciated that when the cover is assembled in that fashion on the sub-assembly of base, tray and ornaments with the end flaps closed, a secure package is formed that will not accidentally or unintentionally open and allow the contents of the cover to spill out. And when the cover is closed, with the base, tray, and ornaments disposed within the cover, all sides of each ornament may be readily viewed because of the transparency of the cover and tray and the light reflective quality of the inner surfaces of the base. Thus, when the package is on display, for example, in a store, display room or other facility, a potential customer viewing the package may quickly appreciate the full beauty of the ornaments on display by seeing all of their sides through the transparent cover and without opening the package. As is evident in FIGS. 1 and 2 , the ornaments may be viewed through the top wall 60 or the portions of the side walls 64 or of the end walls 66 of the cover that are disposed above the upper edges 42 of the side walls 18 and 28 of the base 10 as indicated by the reflected images 44 ′ and lines of sight 86 .
[0022] While the preferred embodiment of the cover has been described in detail, it should be appreciated that other embodiments of covers made of transparent material may be used and achieve many of the advantages of the preferred embodiment described.
[0023] For example, if the cover is of the same shape in plan view as the base and is sized to slip over a portion or all of the side and end walls of the base, and if this embodiment of cover is made of a transparent material, at least with respect to that portion of the cover which lies above the rim of the base, and further if the side walls of the cover extend above the top edges of the side walls of the base, the ornaments packaged therein will be easily viewed just as is described in connection with the preferred embodiment. However, such a cover would not provide a degree of protection provided by the preferred embodiment, and it may be too easy for a customer to open the box and handle the ornaments, and upon deciding to purchase the product, he/she may select another box as opposed to that which the customer opened.
[0024] Alternative constructions are also available for the base. While in the preferred embodiment, the base is very conveniently erected without the use of any adhesive material. More conventional constructions may be employed with separate end and side walls on all sides thereof with such walls being cemented together. It is however, important that the inner surfaces of the walls including the bottom wall be mirror-like to enhance the visibility of the ornaments.
[0025] It is also most advantageous to have the side walls of the tray made of a transparent material so as not to diminish the light reflecting quality of the inner surfaces of the base. However, as an alternative, the inner surfaces of the side walls of the tray may be made of a mirror-like material so as to substitute for the reflective qualities of the side walls of the base that are covered by the tray side walls.
[0026] Having thus described several aspects of at least one embodiment of this invention, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description and drawings are by way of example only. | Packaging for enclosing and displaying frangible items has a base, tray and cover. The base has bottom and side walls that are opaque with their inner surfaces being mirroro-like. A tray sits in the base and is made of a transparent material and has recesses for supporting the items in a position wherein they extend above the side walls of the base. A cover extends beyond the side walls of the tray and extends over the tops of the items and is made of a transparent material enabling the items to be substantially fully viewed through the cover by virtue of the transparent cover, transparent tray and light reflecting side walls of the base. | 1 |
BACKGROUND OF THE INVENTION
In industrial turbines a drastic loss of load is normally sensed by free turbine overspeed and if the overspeed is too severe a fuel cutoff will occur resulting in engine shutdown (trip-out). Complete shutdown from high power may result in engine overstress and/or damage because of the effects of differential expansion, frequently necessitating a long shutdown time in order that the engine may be cooled sufficiently for restarting. This is particularly true when the stator, in contracting, seizes the rotor necessitating a long cooling period before the rotor is again free to turn. Damage would result from such seizing of the rotor.
SUMMARY OF THE INVENTION
A feature of this invention is a method of detecting a rapid loss of applied load to the power turbine permitting a reduction in the fuel supply to a lower power level antecedent to a subsequent overspeed thereby reducing the magnitude of the overspeed and/or avoiding the complete shutdown of the engine.
Another feature is the ability to set a threshold for both the arming level and rate sensitivity to prevent unnecessary nuisance detections during normal operation and/or because of spurious signal noise. Large power load losses from high power will be detected and corrective fuel flow action initiated to limit the turbine overspeed.
According to the present invention a significant reduction in power load on the engine will cause a reduction of fuel flow to a lower threshold, for example 50% power, thereby avoiding complete shutdown by a turbine overspeed. This control is an adjunct to the present controls and has a built-in time delay constant such that small power losses and a normal power transient or momentary power losses will not affect this device and the normal controls will prevail. The device is so structured that should a fuel reduction to the required threshold setting be inadequate and an engine overspeed did occur, the normal overspeed control will be operative to shut the engine down completely.
The foregoing and other objects, features and advantages of the present invention will become more apparent in the light of the following detailed description of preferred embodiments thereof.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic view of the control;
FIG. 2 is a diagram of the load loss detector; and
FIG. 3 is a plot of the pattern when the control is operative.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The engine is represented in the drawing by a gas generator 2 including a compressor 4 and turbine 6 on a shaft 8 and a burner 10 between the compressor and turbine. This gas generator supplies hot gas under pressure to drive a free or power turbine 12 connected by a shaft 14 to a load, for example a generator 16.
Fuel is supplied to the burner from a supply line 18 through a fuel valve 20 and conduit 22 to nozzles 23 in the burner. During normal operation a fuel flow control 26 modulates the valve 20 to provide the desired engine operation. A free turbine speed sensor 24 supplies a speed indication to the control 26 so that the valve 20 is actuated in part as a function of free turbine speed.
The generator delivers electrical power through output lines 28 and the load is sensed by a power sensor 30 through leads 32. This sensor 30 delivers a power sense signal 40 to the control 26 for modulation of the valve 20 as a function of load.
In the event of a sudden substantial loss of power, the load loss detector 34, which is detailed in FIG. 2, comes into operation. The power loss detector circuit operates by modifying power sense signal 40 by a time constant device or lag circuit 42. The lag circuit output 44 is compared with the sensed power signal 40 in comparator device 45 to obtain a signal 47 which is indicative of the rate of power loss. A power level threshold signal 46 is subtracted from signal 47, by device 48 to give a substrate signal 49 the polarity of which is indicative of the rate of power loss relative to the operating power level. A large rapid power loss causes signal 49 to be a positive value. In the event of normal decelerations or small power losses, signal 49 remains negative. A rate threshold circuit comparator 52 discriminates between large, rapid power losses (positive signal) and small power losses (negative signal). In the event of a positive signal 49 (rapid power loss), detector 48 outputs a pulse signal 50 to the control 26, commanding a reduction in fuel flow.
FIG. 3 shows the typical chain of events that occurs during a large loss of power. The power sensor signal 40 shows an immediate loss in power. The time constant signal 44 is in the nature of an exponential decay. The output of comparator circuit 45 is biased by power threshold circuit 46 to make signal 49. Signal 49 is checked for polarity in comparator circuit 52. When a large rapid power loss occurs, as noted by a positive signal in line 49, circuit 48 will output a pulse on signal line 50 to control 26. This signal from the power loss detector circuit 34 will occur before any significant increase in generator speed occurs. The effect of this rapid fuel flow reduction is to reduce the magnitude of the overspeed but still maintain the power plant in operation to avoid a complete shutdown. This prevents the long shutdown time required before the power plant can be restarted.
Obviously, should this device not be effective, that is, if the fuel reduction does not result in a controlled situation with only modest transient turbine overspeed, the usual safety mechanisms would function such that upon reaching a predetermined magnitude of turbine overspeed, the fuel supply would be shut off completely, resulting in a full power plant shutdown. As stated above, this device is intended as an adjunct to the normal turbine controls, and provides a partial fuel reduction control device that will function prior to the normal functioning of a turbine overspeed control mechanism. It has been found that, in a sudden rapid loss of power, which is not a complete power loss, the sensing mechanism signals only a momentary reduction in fuel supply. This reduction is often adequate to prevent turbine overspeed until the normal controls can function to regain control of the power plant.
Although the invention has been shown and described with respect to a preferred embodiment thereof, it should be understood by those skilled in the art that other various changes and omissions in the form and detail thereof may be made therein without departing from the spirit and the scope of the invention. | A method of detecting rapid loss of electrical load in an industrial free turbine prior to significant turbine overspeed and reducing fuel to a predetermined lower power level thereby to avoid the need for a complete shutdown of the engine is disclosed. The method is unaffected by small power losses and by normal transients. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a booster circuit employing a switching element having a triple-well structure.
[0003] 2. Description of the Related Art
[0004] In recent years, flash memories, which are a type of non-volatile semiconductor memory devices, require data read and data write using a single power supply voltage or low power supply voltages, for which, therefore, a booster circuit for supplying a positive or negative boosted voltage is required on a chip when each operation is performed. Also, during CMOS processes, a power supply voltage generated by the booster circuit is used to improve characteristics of an analog circuit.
[0005] Conventionally, there is a known booster circuit employing a triple-well structure switching element (U.S. Pat. Nos. 6,100,557, 6,121,821, and 7,102,422).
[0006] FIG. 25 shows an exemplary conventional booster circuit. In FIG. 25 , 901 indicates a booster circuit which receives two-phase clock signals CLK 1 and CLK 2 and generates an output terminal voltage (boosted voltage) Vpump by a boosting operation. 902 , 903 , and 904 are boosting cells which constitute an exemplary three-stage configuration, where CLK 1 is input to the odd-numbered-stage cells and CLK 2 is input to the even-numbered-stage cell. 905 indicates a backflow preventing circuit which prevents backflow of the boosted voltage Vpump. 906 indicates a charge transfer transistor which functions as a switching element. 907 indicates a P well (PW) of the charge transfer transistor 906 . 908 indicates a deep N well (NT) including the P well 907 . 909 indicates a parasitic diode between the P well 907 and the N well 908 . 910 indicates boosting capacitors which boost output terminals of the boosting cells 902 , 903 , and 904 . 911 , 912 , 913 , and 914 indicate I/O terminals of the boosting cells. As shown in FIG. 25 , the P well 907 and the N well 908 of each charge transfer transistor 906 of the boosting cells 902 to 904 is connected to the source of the charge transfer transistor 906 so that they have the same potential.
[0007] FIG. 26 is a waveform diagram showing the two-phase clock signals CLK 1 and CLK 2 in the booster circuit 901 of FIG. 25 . An operation of the booster circuit 901 of FIG. 25 will be briefly described with reference to FIG. 26 .
[0008] Initially, at time T 1 , CLK 1 goes to “H” (power supply voltage Vdd) and CLK 2 goes to “L” (ground voltage Vss), so that the potentials of the I/O terminals 912 and 914 are boosted. At the same time, changes are transferred from the I/O terminal 912 to the I/O terminal 913 and from the I/O terminal 914 to the output terminal of the booster circuit 901 , via the charge transfer transistors 906 of the boosting cell 903 and the backflow preventing circuit 905 , respectively, so that the output terminal voltages of the I/O terminal 913 and the booster circuit 901 are increased. In this case, since the P well 907 of each of the boosting cell 903 and the backflow preventing circuit 905 has the same potential as that of the source terminal of the charge transfer transistor 906 , the substrate biasing effect of the charge transfer transistor 906 is suppressed, thereby making it possible to suppress a decrease in charge transfer efficiency.
[0009] At time T 2 when a charge transfer period Ttrans has been passed since time T 1 , CLK 2 goes to “H” and CLK 1 goes to “L”, so that the potential of the I/O terminal 913 is boosted. At the same time, charges are transferred from the I/O terminal 913 to the I/O terminal 914 via the charge transfer transistor 906 of the boosting cell 904 . In this case, since the P well 907 of the boosting cell 904 has the same potential as that of the source terminal of the charge transfer transistor 906 , the substrate biasing effect of the charge transfer transistor 906 is suppressed, thereby making it possible to suppress a decrease in charge transfer efficiency.
[0010] At time T 3 , an operation similar to that at time T 1 is performed.
[0011] Thus, according to the booster circuit 901 of FIG. 25 , the substrate biasing effect is suppressed, thereby making it possible to suppress a decrease in charge transfer efficiency during the boosting operation.
[0012] However, in the conventional booster circuit 901 , the source and the N well 908 of the charge transfer transistor 906 are connected to each other, so that a parasitic capacitance formed by the N well 908 is charged and discharged by voltage transition widths of the clock signals CLK 1 and CLK 2 in response to voltage transitions of the clock signals CLK 1 and CLK 2 .
[0013] Also, charges supplied by the clock signals CLK 1 and CLK 2 are used to charge and discharge the N well 908 , disadvantageously resulting in a decrease in boost efficiency.
[0014] Also, since the source and the N well 908 of the charge transfer transistor 906 are connected to each other, it is necessary to separate the N wells 908 of the charge transfer transistors 906 from each other, disadvantageously resulting in an increase in layout area.
SUMMARY OF THE INVENTION
[0015] An object of the present invention is to provide a booster circuit in which the current consumption and the layout area can be suppressed while the substrate biasing effect of a switching element used in each boosting cell can be suppressed.
[0016] To achieve the object, a booster circuit according to the present invention is provided in which the potential of an N well of each boosting cell is fixed to the input or output potential of the boosting cell stage to reduce the amount of charges which are charged and discharged between the N well and the substrate, thereby making it possible to improve the boost efficiency.
[0017] Specifically, in a first aspect, a boosting circuit comprises boosting cells each having a first-conductivity type first well region on a substrate, a second-conductivity type second well region in the first well region, and at least one switching element in the first well region or the second well region, in which the at least one switching element switches ON/OFF a connection between a first terminal and a second terminal so as to transfer charges from the first terminal to the second terminal, a first boosting cell row including N stages (N≧1) of the boosting cells, a second boosting cell row including M stages (M≧1) of the boosting cells, and at least one analog comparison circuit for outputting the higher or lower of an output potential of the boosting cell on the i-th stage (1≦i≦N) of the first boosting cell row and an output potential of the boosting cell on the i-th stage (1≦i≦M) of the second boosting cell row. The output potential of the at least one analog comparison circuit is applied to the first well region of the at least one switching element included in the boosting cell on the (i+1)-th stage, the boosting cell on the i-th stage, or at least one of the boosting cells on less than i-th stages of the first and second boosting cell rows.
[0018] In a second aspect, a booster circuit comprises boosting cells each having a first-conductivity type first well region on a substrate, a second-conductivity type second well region in the first well region, and at least one switching element in either or both of the first well region and the second well region, in which the at least one switching element switches ON/OFF a connection between a first terminal and a second terminal so as to transfer charges from the first terminal to the second terminal, a first boosting cell row including N stages (N≧1) of the boosting cells, a second boosting cell row including M stages (M≧1) of the boosting cells, and at least one analog comparison circuit for outputting the higher or lower of an input potential of the boosting cell on the i-th stage (1≦i≦N) of the first boosting cell row and an input potential of the boosting cell on the i-th stage (1≦i≦M) of the second boosting cell row. The output potential of the at least one analog comparison circuit is applied to the first well region of the at least one switching element included in the boosting cell on the (i+1)-th stage, the boosting cell on the i-th stage, or at least one of the boosting cells on less than i-th stages of the first and second boosting cell rows.
[0019] In a third aspect, a booster circuit comprises boosting cells and backflow preventing circuits each having a first-conductivity type first well region on a substrate, a second-conductivity type second well region in the first well region, and at least one switching element in the first well region or the second well region, wherein the at least one switching element switches ON/OFF a connection between a first terminal and a second terminal so as to transfer charges from the first terminal to the second terminal, a first boosting cell row including N stages (N≧1) of the boosting cells and the backflow preventing circuit, a second boosting cell row including M stages (M≧1) of the boosting cells and the backflow preventing circuit, and at least one analog comparison circuit for outputting the higher or lower of an output potential of the boosting cell on the i-th stage (1≦i≦N) of the first boosting cell row and an output potential of the boosting cell on the i-th stage (1≦i≦M) of the second boosting cell row. The output potential of the at least one analog comparison circuit is applied to the first well region of the at least one switching element included in the backflow preventing circuit, the boosting cell on the (i+1)-th stage, the boosting cell on the i-th stage, or at least one of the boosting cells on less than i-th stages of the first and second boosting cell rows.
[0020] In a fourth aspect, a booster circuit comprises boosting cells and backflow preventing circuits each having a first-conductivity type first well region on a substrate, a second-conductivity type second well region in the first well region, and at least one switching element in either or both of the first well region and the second well region, in which the at least one switching element switches ON/OFF a connection between a first terminal and a second terminal so as to transfer charges from the first terminal to the second terminal, a first boosting cell row including N stages (N≧1) of the boosting cells and the backflow preventing circuit, a second boosting cell row including M stages (M≧1) of the boosting cells and the backflow preventing circuit, and at least one analog comparison circuit for outputting the higher or lower of an intermediate potential of the backflow preventing circuit of the first boosting cell row and an intermediate potential of the backflow preventing circuit of the second boosting cell row. The output potential of the at least one analog comparison circuit is applied to the first well region of the at least one switching element included in the backflow preventing circuit of the first and second boosting cell rows or at least one of the boosting cells of the first and second boosting cell rows.
[0021] In a fifth aspect, a booster circuit comprises boosting cells and backflow preventing circuits each having a first-conductivity type first well region on a substrate, a second-conductivity type second well region in the first well region, and at least one switching element in either or both of the first well region and the second well region, in which the at least one switching element switches ON/OFF a connection between a first terminal and a second terminal so as to transfer charges from the first terminal to the second terminal, a first boosting cell row including N stages (N≧1) of the boosting cells and the backflow preventing circuit, a second boosting cell row including M stages (M≧1) of the boosting cells and the backflow preventing circuit, and at least one analog comparison circuit for comparing input potentials of the boosting cells on the i-th stages (1≦i≦N) of the first and second boosting cell rows or the backflow preventing circuits and outputting the higher or lower of the input potentials. The output potential of the at least one analog comparison circuit is applied to the first well region of the at least one switching element included in the backflow preventing circuit, the boosting cell on the (i+1)-th stage, the boosting cell on the i-th stage, or at least one of the boosting cells on less than i-th stages of the first and second boosting cell rows.
[0022] In a sixth aspect, in the booster circuit of any one of the first to fifth aspects, the second well region and the first terminal are connected to each other so that the second well region and the first terminal have the same potential.
[0023] In a seventh aspect, in the booster circuit of any one of the first to fifth aspects, the second well region and the first well region are connected to each other so that the second well region and the first well region have the same potential.
[0024] In an eighth aspect, in the booster circuit of any one of the first to fifth aspects, the at least one analog comparison circuit has a first-conductivity type first well region on the substrate, a second-conductivity type second well region in the first well region, and at least one switching element in the first well region or the second well region, and the at least one analog comparison circuit is provided one for each boosting cell stage.
[0025] In a ninth aspect, in the booster circuit of any one of the first to fifth aspects, the at least one analog comparison circuit has a first-conductivity type first well region on the substrate, a second-conductivity type second well region in the first well region, and at least one switching element in the first well region or the second well region, and the at least one analog comparison circuit is provided one every arbitrary number of boosting cell stages.
[0026] In a tenth aspect, in the booster circuit of any one of the first to fifth aspects, a diode element is provided between the first terminal and the first well region of the boosting cell.
[0027] In an eleventh aspect, in the booster circuit of any one of the first to fifth aspects, the at least one switching elements having the same potential of the first well region of the first and second boosting cell rows share a common first well region.
[0028] In a twelfth aspect, in the booster circuit of any one of the first to fifth aspects, the at least one switching elements having the same potential of the first well region of the first and second boosting cell rows and the at least analog comparison circuit share a common first well region.
[0029] In a thirteenth aspect, in the booster circuit of any one of the first to fifth aspects, the at least one switching circuit of the boosting cell on the i-th stage of the first boosting cell row and a first element of the at least analog comparison circuit share a common first well region, and the at least one switching circuit of the boosting cell on the i-th stage of the second boosting cell row and a second element of the at least analog comparison circuit share a common first well region.
[0030] According to the first aspect, the amount of charges which are charged and discharged in the first-conductivity type first well region can be caused to be smaller than the voltage swing of a clock signal, so that the apparent parasitic capacitance between the first well region and the substrate can be reduced. Thereby, it is possible to suppress current consumption during a boosting operation. Also, since the apparent parasitic capacitance between the first well region and the substrate can be reduced, boost efficiency can be improved. Also, by controlling the potentials of the first well regions of a plurality of boosting cells using a single analog comparison circuit, it is possible to suppress an increase in layout area due to the analog comparison circuit.
[0031] According to the second aspect, a well control can be performed using the input potential of a boosting cell on the first stage, so that a load capacitance connected to a boosting capacitor on each stage can be caused to be uniform. Thereby, a more stable boosting operation can be achieved.
[0032] According to the third aspect, the potential of the first well region of the backflow preventing circuit can be controlled, thereby making it possible to suppress a decrease in charge transfer efficiency of the backflow preventing circuit.
[0033] According to the fourth aspect, a well control can be performed using an intermediate potential of the backflow preventing circuit, so that a load capacitance connected to a boosting capacitor on each stage can be caused to be uniform. Thereby, a more stable boosting operation can be achieved.
[0034] According to the fifth aspect, a well control can be performed using the input potential of a boosting cell on the first stage, so that a load capacitance connected to a boosting capacitor on each stage can be caused to be uniform. Thereby, a more stable boosting operation can be achieved.
[0035] According to the sixth aspect, the input terminal and the second well region of a charge transfer transistor (switching element) in the boosting cell can be connected to each other, so that the current drive performance of a switching element can be suppressed from being decreased due to the substrate biasing effect.
[0036] According to the seventh aspect, the first well region and the second well region are caused to have the same potential, so that a single well region can be shared by an N-channel transistor and a P-channel transistor, resulting in a decrease in layout area.
[0037] According to the eighth aspect, an analog comparison circuit is provided for each of all stages, so that the boosting cells can be caused to be of uniform parasitic capacitance, thereby making it possible to improve easiness of design.
[0038] According to the ninth aspect, an analog comparison circuit is provided every arbitrary number of stages, so that an increase in circuit area can be suppressed while securing the margins of the breakdown voltages of the second well region and the first well region.
[0039] According to the tenth aspect, by supplying the input potential of a boosting cell to the first well region via a diode element, the potential increase of the first well region is caused to follow each boosting cell potential during start up of a booster circuit, thereby making it possible to prevent the occurrence of latch-up.
[0040] According to the eleventh and twelfth aspects, a common first well region is used, thereby making it possible to reduce the layout area.
[0041] According to the thirteenth aspect, noise interference between the first boosting cell row and the second boosting cell row which is pumped with clocks having different phases can be reduced while reducing the amount of charges which are charged and discharged of the first well region.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIG. 1 is a circuit diagram showing an exemplary configuration of a booster circuit according to the present invention.
[0043] FIG. 2 is a circuit diagram showing another exemplary configuration of a booster circuit according to the present invention.
[0044] FIG. 3 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0045] FIG. 4 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0046] FIG. 5 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0047] FIG. 6 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0048] FIG. 7 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0049] FIG. 8 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0050] FIG. 9 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0051] FIG. 10 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0052] FIG. 11 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0053] FIG. 12 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0054] FIG. 13 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0055] FIG. 14 is a circuit diagram showing still another exemplary configuration of the booster circuit of the present invention.
[0056] FIG. 15 is a plan view showing an exemplary layout configuration of the booster circuit of the present invention.
[0057] FIG. 16 is a plan view showing another exemplary layout configuration of the booster circuit of the present invention.
[0058] FIG. 17 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0059] FIG. 18 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0060] FIG. 19 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0061] FIG. 20 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0062] FIG. 21 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0063] FIG. 22 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0064] FIG. 23 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0065] FIG. 24 is a plan view showing still another exemplary layout configuration of the booster circuit of the present invention.
[0066] FIG. 25 is a circuit diagram showing a conventional booster circuit.
[0067] FIG. 26 is a waveform diagram showing a two-phase clock signal in the booster circuit of FIG. 25 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0068] Hereinafter, a booster circuit according to the present invention will be described, by way of examples, with reference to the accompanying drawings.
[0069] FIG. 1 shows an exemplary configuration of the booster circuit of the present invention. In FIG. 1 , 101 indicates a two-parallel booster circuit which receives two-phase clock signals CLK 1 and CLK 2 and generates an output terminal voltage (boosted voltage) Vpump by a boosting operation. 102 , 103 , 104 , 105 , 106 , and 107 indicate boosting cells which are arranged in a first line and a second line, where CLK 1 is input to the odd-numbered stages on the first line and the even-numbered stages on the second line, and CLK 2 is input to the even-numbered stages on the first line and the odd-numbered stages on the second line. 108 and 109 indicate backflow preventing circuits which prevent backflow of the boosted voltage Vpump. 110 , 111 , 112 , 113 , 114 , 115 , and 116 indicate I/O terminals of the boosting cells 102 to 107 . 117 , 118 , and 119 indicate exemplary low-voltage output analog comparison circuits which output the lower of the voltages of the I/O terminals of the boosting cells on the same stage of the first line and the second line. 120 and 121 indicate Nch (N-channel) transistors included in the low-voltage output analog comparison circuits 117 , 118 , and 119 . 122 , 123 , and 124 indicate output terminals of the low-voltage output analog comparison circuits 117 to 119 connected to N wells of the corresponding boosting cells. 125 indicates a high-voltage output analog comparison circuit which outputs the higher of the voltages of the I/O terminal 113 of the third-stage boosting cell 104 on the first line and the I/O terminal 116 of the third-stage boosting cell 107 on the second line. 126 and 127 indicate Pch (P-channel) transistors included in the high-voltage output analog comparison circuit 125 . 128 indicates an output terminal of the high-voltage output analog comparison circuit connected to N wells of the backflow preventing circuits 108 and 109 . Note that the same elements as those of the above-described conventional example are indicated by the same reference numerals. Also, the number of boosting cells connected in series in the booster circuit 101 shown in FIG. 1 is only for illustrative purposes.
[0070] The two-phase clock signals CLK 1 and CLK 2 of the booster circuit 101 of FIG. 1 have waveforms similar to those of FIG. 26 . An operation of the booster circuit 101 of FIG. 1 will be described with reference to FIG. 26 .
[0071] At time T 1 , CLK 1 goes from “L” to “H” and CLK 2 goes from “H” to “L”, so that the potentials of the I/O terminals 111 , 113 , and 115 of the boosting cells 102 , 104 , and 106 are boosted, and the boosted charges are transferred via the charge transfer transistors 906 of the boosting cell 103 , the backflow preventing circuit 108 , and the boosting cell 107 to the I/O terminal 112 , the output terminal of the booster circuit 101 , and the I/O terminal 116 , respectively. In this case, in the low-voltage output analog comparison circuit 117 , the Nch transistor 120 is switched OFF and the Nch transistor 121 is switched ON due to a relationship in potential between the boosted I/O terminal 111 and the non-boosted I/O terminal 114 , so that the potential of the I/O terminal 114 is output from the output terminal 122 of the low-voltage output analog comparison circuit 117 and is supplied to the N wells of the boosting cell 102 and the boosting cell 105 . Similarly, the potential of the I/O terminal 112 is output from the output terminal 123 of the low-voltage output analog comparison circuit 118 and is supplied to the N wells of the boosting cell 103 and the boosting cell 106 . The potential of the I/O terminal 116 is output from the output terminal 124 of the low-voltage output analog comparison circuit 119 and is supplied to the N wells of the boosting cells 104 and the boosting cell 107 . Also, in the high-voltage output analog comparison circuit 125 , the Pch transistor 126 is switched ON and the Pch transistor 127 is switched OFF due to a relationship in potential between the boosted I/O terminal 113 and the non-boosted I/O terminal 116 , so that the potential of the I/O terminal 113 is output from the output terminal 128 of the high-voltage output analog comparison circuit 125 and is supplied to the N wells of the backflow preventing circuit 108 and the backflow preventing circuit 109 .
[0072] At time T 2 , if CLK 1 goes from “H” to “L” and CLK 2 goes from “L” to “H”, the potentials of the I/O terminals 112 , 114 , and 116 of the boosting cells 103 , 105 , and 107 are boosted, and boosted charges are transferred via the charge transfer transistors 906 of the boosting cells 104 and 106 and the backflow preventing circuit 109 to the output terminals of the I/O terminals 113 and 115 and the booster circuit 101 , respectively. In this case, in the low-voltage output analog comparison circuit 117 , the Nch transistor 120 is switched ON and the Nch transistor 121 is switched OFF due to a relationship in potential between the boosted I/O terminal 114 and the non-boosted I/O terminal 111 , so that the potential of the I/O terminal 111 is output from the output terminal 122 of the low-voltage output analog comparison circuit 117 and is supplied to the N wells of the boosting cell 102 and the boosting cell 105 . Similarly, the potential of the I/O terminal 115 is output from the output terminal 123 of the low-voltage output analog comparison circuit 118 and is supplied to the N wells of the boosting cell 103 and the boosting cell 106 . The potential of the I/O terminal 113 is output from the output terminal 124 of the low-voltage output analog comparison circuit 119 and is supplied to the N wells of the boosting cell 104 and the boosting cell 107 . Also, in the high-voltage output analog comparison circuit 125 , the Pch transistor 126 is switched OFF and the Pch transistor 127 is switched ON due to a relationship in potential between the boosted I/O terminal 116 and the non-boosted I/O terminal 113 , so that the potential of the I/O terminal 116 is output from the output terminal 128 of the high-voltage output analog comparison circuit 125 and is supplied to the N wells of the backflow preventing circuit 108 and the backflow preventing circuit 109 .
[0073] Thus, according to the booster circuit 101 of FIG. 1 , the potentials of the N wells of the boosting cells 102 to 107 and the backflow preventing circuits 108 and 109 can be fixed to the input potentials or the output potentials of the respective boosting cell stage, so that the amount of charges which are charged and discharged between the N well and the substrate can be reduced, i.e., current consumption can be reduced. Also, by reducing the amount of charges which are charged and discharged between the N well and the substrate, the amount of charges transferred to the next stage can be increased, so that an improvement in boost efficiency can be expected.
[0074] Note that, as shown in FIGS. 2 and 3 , the low-voltage output analog comparison circuits 117 to 119 and the high-voltage output analog comparison circuit 125 can be provided every arbitrary number of stages of boosting cells, taking into consideration the margin of the breakdown voltage between the P well and the N well and the circuit area, so that an effect similar to that of the above-described configuration can be obtained with a reduced number of elements.
[0075] FIG. 4 shows another exemplary configuration of the booster circuit of the present invention. In FIG. 4 , 701 indicates a two-parallel booster circuit which receives two-phase clock signals CLK 1 and CLK 2 , and generates a boosted voltage Vpump by a boosting operation. 702 , 703 , 704 , 705 , 706 , and 707 indicate the boosting cells 102 to 107 of FIG. 1 , respectively, in each of which a transistor 710 diode-connected between the I/O terminal of the boosting cell and the output terminal 128 of the high-voltage output analog comparison circuit 125 is added. 708 and 709 indicate backflow preventing circuits. Note that elements similar to those of FIG. 1 are indicated by the same reference numerals. The number of boosting cells connected in series in the booster circuit 701 is only for illustrative purposes.
[0076] The configuration of FIG. 4 is different from that of FIG. 1 in that the low- (or high-) voltage output analog comparison circuits 117 to 119 and 125 are replaced with a single common element, thereby reducing the number of elements. Thereby, during startup of the booster circuit 701 , when the potentials of the I/O terminals 111 to 116 of the boosting cells 702 to 707 increase, the N well potential is supplied as a forward current of the parasitic diode 909 from the P well 907 of each of the boosting cells 702 to 707 . To suppress the forward current of the parasitic diode 909 , the transistor 710 having a diode function is provided, thereby making it possible to provide a stable boosting operation even during startup of the booster circuit 701 .
[0077] FIG. 5 shows still another exemplary configuration of the booster circuit of the present invention. In FIG. 5 , 621 indicates a two-parallel booster circuit which receives two-phase clock signals CLK 1 and CLK 2 , and generates a boosted voltage Vpump by a boosting operation. 858 and 859 indicate backflow preventing circuits in which two-phase clock signals CLK 1 and CLK 2 are input and transistors 861 and 862 therein are controlled to cause a charge transfer transistor 860 to be in a conductive or non-conductive state. Thereby, a decrease in transfer efficiency occurring in the backflow preventing circuits 108 and 109 of FIG. 1 is suppressed. Note that elements similar to those of FIG. 1 are indicated by the same reference numerals. The number of boosting cells connected in series in the booster circuit 621 is only for illustrative purposes.
[0078] The configuration of FIG. 5 is different from that of FIG. 5 in that the two-phase clock signals CLK 1 and CLK 2 are input to control the gate potential of the charge transfer transistor 860 , and a low-voltage output analog comparison circuit 501 is used for the backflow preventing circuits 858 and 859 for improving charge transfer efficiency and boost efficiency.
[0079] According to FIG. 5 , the low-voltage output analog comparison circuits 117 , 118 , 119 , and 501 having a similar structure are provided on the respective stages in the booster circuit 621 , so that a difference between the loads of the boosting capacitors 910 of the boosting cells 104 and 107 on the final stage of FIG. 1 and the loads of the boosting capacitors 910 of the other boosting cells 102 , 103 , 105 , and 106 can be suppressed, thereby making it possible to cause the boosting capacitors 910 on the stages to be of substantially uniform parasitic capacitance. Therefore, the boosting cells on the stages are caused to be of uniform charge transfer amount, resulting in a stable boosting operation.
[0080] Note that a booster circuit 622 of FIG. 6 is an example in which high-voltage output analog comparison circuits 511 , 512 , 513 , and 125 are used for the boosting cells 102 to 107 and the backflow preventing circuits 108 and 109 of FIG. 1 , and only the gates of the transistors 126 and 127 of the high-voltage output analog comparison circuit 511 which controls the N wells of the boosting cells 102 and 105 on the first stage are fixed to VSS. Thereby, a stable boosting operation can be achieved as in FIG. 5 .
[0081] Thus, the booster circuits employing the two-phase clock signals CLK 1 and CLK 2 have been described as exemplary booster circuit configurations. Alternatively, as shown in FIG. 7 , a booster circuit 801 may employ four-phase clock signals CLK 1 , CLK 2 , CLK 3 , and CLK 4 . Alternatively, as shown in FIGS. 8 , 9 , 10 , and 11 , booster circuit 851 , 881 , 601 , and 611 may employ two-phase clock signals CLK 1 and CLK 2 , and Nch transistors having triple wells in boosting cells, where the low-voltage output analog comparison circuits 117 to 119 , and 501 or the high-voltage output analog comparison circuits 511 to 513 and 125 are used, thereby making it possible to a similar effect irrespective of the configuration of the boosting cell. Also, as shown in FIG. 11 , the P and N wells of an Nch transistor 612 of each of boosting cells 602 to 607 can be commonly connected, and further, the P and N wells of an Nch transistor 612 and the N well of the Pch transistor 611 can be commonly connected, thereby making it possible to reduce the layout area.
[0082] Note that, in FIG. 7 , 802 , 803 , 804 , 805 , 806 , and 807 indicate boosting cells, 808 and 809 indicate backflow preventing circuits, 810 indicates a charge transfer transistor (Nch transistor), 811 and 813 indicates Nch transistors, and 812 indicates a boosting capacitor. In FIG. 8 , 852 , 853 , 854 , 855 , 856 , and 857 indicate boosting cells, 858 and 859 indicate backflow preventing circuits, 860 indicates a charge transfer transistor (Nch transistor), 861 and 863 indicate Nch transistors, and 862 indicates a Pch transistor. In FIGS. 10 and 11 , 602 , 603 , 604 , 605 , 606 , and 607 indicate boosting cells, 608 and 609 indicate backflow preventing circuits, 610 and 612 indicate charge transfer transistors (Nch transistors), 611 and 614 indicate charge transfer transistors (Pch transistors), and 613 indicates a connection node.
[0083] FIGS. 12 , 13 , and 14 show exemplary configurations including high-voltage (low-voltage) output analog comparison circuits, where either or both high- and low-voltage output analog comparison circuits can be used for all boosting cells and a backflow preventing circuit. If a boosting operation can be operated irrespective of the number of transistors (charge transfer transistors in the N wells of boosting cells, etc.) or the presence or absence of a Pch transistor and even when the P well is not necessarily connected directly to the source (e.g., the P well of the Nch transistor in a charge transfer transistor or the like is connected to the N well, the potential of the P well is supplied by switching the potentials of the drain and the source, etc.), a similar effect can be achieved.
[0084] The configuration of the low-voltage output analog comparison circuits 117 to 119 and 501 and the high-voltage output analog comparison circuits 511 , 512 , 513 , and 125 in the figures is only for illustrative purposes, and any other configurations that provide similar functions may be provided.
[0085] FIG. 15 is a plan view showing an exemplary layout configuration of booster circuits according to the present invention, indicating the charge transfer transistors 906 of the boosting cells 102 to 107 and the low-voltage output analog comparison circuits 117 to 119 of FIG. 1 .
[0086] In FIG. 15 , the output terminal 122 (or 123 , 124 ) of the low-voltage output analog comparison circuit 117 (or 118 , 119 ) is connected to a single N well (NT) which is shared by the charge transfer transistors 906 of the boosting cells 102 and 105 (or 103 and 106 , 104 and 107 ).
[0087] According to FIG. 15 , a single N well can be shared by the triple-well structure switching elements 906 of the two or more boosting cells 102 and 105 controlled by the output voltage of the low-voltage output analog comparison circuit 117 , thereby making it possible to reduce the layout area.
[0088] Note that the layout configuration of FIG. 15 is only for illustrative purposes. Alternatively, as shown in FIGS. 16 and 17 , the N well of the switching element 906 which is controlled by the output voltage of the low-voltage output analog comparison circuit 118 can be separated or shared irrespective of the number of stages of boosting cells.
[0089] Further, as shown in FIGS. 18 and 19 , a single N well can be shared by the low-voltage output analog comparison circuits 117 to 119 u and the switching elements 906 of the boosting cells 102 to 107 , respectively.
[0090] As shown in FIGS. 20 and 21 , a single N well is shared by the transistors 120 of the single low-voltage output analog comparison circuits 117 , 118 , 119 , and 501 , and the boosting cells 102 , 103 , and 104 and the backflow preventing circuit 108 , and another single N well is shared by the transistors 121 of the low-voltage output analog comparison circuits 117 , 118 , 119 , and 501 , and the boosting cells 105 , 106 , and 107 and the backflow preventing circuit 109 . Thereby, the influence of noise in the boosting capacitor can be reduced while decreasing the amount of charges which are charged and discharged of the N well, thereby making it possible to achieve a stable boosting operation.
[0091] A similar layout can be applied to the high-voltage output analog comparison circuits 511 , 512 , 513 , and 125 as shown in FIGS. 22 , 23 , and 24 .
[0092] The above-described layout is only for illustrative purposes. A plurality of transistors having the same potential can share a single N or P well irrespective of the boosting cell row.
[0093] Further, in each of the above aspects, the output voltage generated by the analog comparison circuit in the boosting cell on the i-th stage can be applied to the N well of any of the boosting cells on the (i+1)-th stage, i-th stage, and stages anterior the i-th stage in the booster circuit in the N-th row other than the booster circuits in the first and second rows. This achieves not only reduction in area of the analog comparison circuit but also layout sharing to thus reduce the layout area.
[0094] As described above, in the booster circuit of the present invention, the substrate biasing effect can be suppressed in the triple-well structure element included in each boosting cell, so that the current consumption, the circuit area, and the layout area can be reduced. Therefore, the booster circuit of the present invention is useful as a power supply generating circuit or the like for improving analog circuit characteristics in a non-volatile semiconductor memory device and a CMOS process.
[0095] Also, the booster circuit of the present invention is applicable to power supply circuits for a volatile semiconductor memory device (DRAM, etc.), a liquid crystal device, a mobile device, and the like. | A boosting circuit comprises a first boosting cell row and a second boosting cell row. The boosting circuit further comprises an analog comparison circuit for comparing the potential of boosting cells on the same stage, and selecting and outputting the lower or higher of the potentials. The potential of an N well is controlled using the output potential of the analog comparison circuit. Thereby, the amplitude of an N well potential can be suppressed, and a single N well region can be shared. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates generally to the device configuration and manufacturing methods for fabricating the semiconductor power devices. More particularly, this invention relates to an improved and novel device configuration and manufacturing process for providing trench Metal-Oxide-Semiconductor-Field-Effect-Transistor (MOSFET) with split trenched gate structures in cell corners for gate charge reduction.
BACKGROUND OF THE INVENTION
[0002] Conventional trench Metal-Oxide-Semiconductor-Field-Effect-Transistor (MOSFET) comprises either closed cell array or stripe cell array. Compared to that having stripe cell array, trench MOSFET having closed cell array has lower Rds (resistance between drain and source, similarly hereinafter) resulted from a greater channel length. However, it also has disadvantage of higher Qgd (gate charge between gate and drain, similarly hereinafter) contributed from inherent existence of intersection area among the closed cells.
[0003] Please refer to FIG. 1 for top view of a conventional N-channel trench MOSFET having closed cells with truncated corners of prior art. The Qgd aforementioned of the N-channel trench MOSFET is composed of Qgd 1 and Qgd 2 , wherein Qgd 1 is the gate charge between gate and drain in the intersection area (as illustrated in FIG. 1 ) among the truncated corners of the closed cells, as shown in FIG. 2A of C 1 -D 1 cross section of FIG. 1 , and Qgd 2 is the gate charge between gate and drain in non-intersection area of trenched gates, as shown in FIG. 2B of A 1 -B 1 cross section of FIG. 1 . When unit cell (as illustrated in FIG. 1 ) has 1.0 um pitch, the portion of Qgd 1 contributes about 40% of total Qgd due to a large area in the trenched gates intersection area.
[0004] For more detailed, please refer to FIG. 2B for A 1 -B 1 cross-sectional view of FIG. 1 , where a trenched source-body contact 102 having top view of rectangular shape is formed with vertical sidewall and located in center portion between every two trenched gates 108 which induce Qgd 2 in each unit cell. A plurality of n+ source regions 104 encompassed in P body regions 106 are formed having uniform doping profile distributed from the vertical sidewall of the trenched source-body contact 102 to channel region near the trenched gates 108 filled with doped poly-silicon layer.
[0005] Accordingly, it would be desirable to provide a new and improved trench MOSFET configuration and manufacturing method to reduce Qgd in closed cell structure without increasing Rds.
SUMMARY OF THE INVENTION
[0006] It is therefore an aspect of the present invention to provide a new and improved trench MOSFET by forming split trenched gates in cell corners in each trenched gates intersection area. Meanwhile, an insulation layer is formed between the split trenched gates with thick bottom thermal oxide layer underneath in center portion of the trenched gates intersection area. Therefore, Qgd 1 is reduced because the center portion of the trenched gates intersection area is the composite oxide layer not poly-silicon layer.
[0007] Another aspect of the present invention is to form a doped area with dopant type opposite to epitaxial layer to further reduce Qgd 1 by surrounding the split trenched gates underneath each the trenched gates intersection area.
[0008] Briefly, in a preferred embodiment, this invention disclosed a trench MOSFET comprising a plurality of closed cells with a substantial square shape for each cell, formed in an epitaxial layer of a first conductivity type onto a substrate of the first conductivity type, further comprising a plurality of trenched gates, wherein each trenched gates intersection area in cell corners comprising: split trenched gates along trench sidewalls of the trenched gates, wherein the trench sidewalls are padded with a gate oxide layer; an insulation layer covering top surface of the trenched gates and the epitaxial layer, and disposed between the split trenched gates; one thermally grown oxide layer formed between the insulation layer and the split trenched gates; another thermally grown oxide layer formed underneath the insulation layer in center portion of each the trenched gates intersection area, having thicker oxide than the gate oxide layer.
[0009] In an exemplary embodiment, the trench MOSFET further comprises: a plurality of source regions of the first conductivity type encompassed in body regions of second conductivity type in upper portion of the epitaxial layer and extending between every two adjacent of the trenched gates; a trenched source-body contact in each the closed cell and penetrating through the insulation layer covering the epitaxial layer, and further extending between through the source region and into the body region to connect the source region and the body region to a source metal covering top surface of the insulation layer; an ohmic body doped region of the second conductivity type encompassed in the body region and wrapping at least bottom of each the trenched source-body contact underneath the source region, wherein the ohmic body doped region has a higher doping concentration than the body region. In an exemplary embodiment, the trench MOSFET further comprises a on-resistance reduction doped region of the first conductivity type surrounding bottom of each the trenched gate and the trenched gates intersection area, wherein the on-resistance reduction doped area has a higher doping concentration than the epitaxial layer. In an exemplary embodiment, the trench MOSFET further comprises a gate-drain charge reduction doped region of the second conductivity type surrounding bottom of each the trenched gates intersection area. In an exemplary embodiment, the trench MOSFET further comprises a void existing between the split trenched gates in each the trenched gates intersection area. In an exemplary embodiment, the source region has a Gaussian distribution profile from sidewalk of the trenched source-body contact to adjacent channel regions near the trenched gates. In an exemplary embodiment, the trenched source-body contact has slope sidewalls and the ohmic body doped region surrounds bottom and sidewall of the trenched source-body contact underneath the source region. In an exemplary embodiment, the trenched gates have rounded trenched gates corners and the trenched source-body contact has circular shape form top view.
[0010] Furthermore, this invention discloses to method to manufacture a trench MOSFET comprising the steps of: opening a plurality of gate trenches in an epitaxial layer of a first conductivity type; carrying out ion implantation of the first conductivity type dopant above the gate trenches to form a on-resistance reduction doped region in the epitaxial layer and surrounding bottom of each the gate trenches as well as each trenched gates intersection area, wherein the doping concentration of the on-resistance reduction doped region is higher than that of the epitaxial layer; forming a gate oxide layer covering top surface of the epitaxial layer, and along inner surface of the gate trenches and the trenched gates intersection area; depositing a doped poly-silicon layer onto the gate oxide layer and etching the doped poly-silicon layer to a pre-determined depth; carrying out a body ion implantation of second conductivity type dopant to form body regions in upper portion of the epitaxial layer; applying a poly mask and performing dry poly-silicon etching to form a poly-silicon hole in center portion of the doped poly-silicon layer in the trenched gates intersection area, wherein the poly hole extends from top surface of the doped poly-silicon layer in the trenched gates intersection area to expose the gate oxide on bottom of the trenched gates intersection area; carrying out an ion implantation of the second conductivity type dopant to form a gate-drain charge reduction doped region of the second conductivity type below the poly-silicon hole; Carrying out a body diffusion to form the body regions of the second conductivity type as well as gate-drain charge reduction doped region underneath the trenched gates intersection area; depositing an insulation layer onto entire top surface and filling into the poly hole; providing a contact mask and carrying out a dry oxide etching to open contact openings through the insulation layer; carrying out ion implantation of the first conductivity type and diffusion step to form source regions in upper portion of the body regions with a Gaussian distribution profile form edge of the contact openings to adjacent channel regions near the gate trenches; carrying out a dry silicon etching to make the contact openings further extending through the source regions and into the body regions to form contact trenches; carrying out ion implantation of the second conductivity type and followed by a step of RTA to form an ohmic body doped region in the body regions and surrounding at least bottom of each the contact trench underneath the source regions, wherein the ohmic body doped region has higher doping concentration than the body region; depositing a barrier layer overlying inner surface of the contact trenches and top surface of the insulation layer; depositing a metal material onto a barrier metal layer and etching back the metal material leaving it within the contact trenches; etching back the barrier layer removing it from top surface of the insulation layer; depositing a front metal layer onto top surface of the insulation layer and covering the metal material to function as a source metal.
[0011] These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiment, which is illustrated in the various drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:
[0013] FIG. 1 is a top view of a trench MOSFET with closed cells of prior art.
[0014] FIG. 2A is C 1 -D 1 cross section of the trench MOSFET in FIG. 1 .
[0015] FIG. 2B is A 1 -B 1 cross section of the trench MOSFET in FIG. 1 .
[0016] FIG. 3 is a top view of a trench MOSFET according to the present invention.
[0017] FIG. 4A is a preferred A 2 -B 2 cross section of the trench MOSFET in FIG. 3 according to the present invention.
[0018] FIG. 4B is a preferred C 2 -D 2 cross section of the trench MOSFET in FIG. 3 according to the present invention.
[0019] FIG. 5A is another preferred A 2 -B 2 cross section of the trench MOSFET in FIG. 3 according to the present invention.
[0020] FIG. 5B is another preferred C 2 -D 2 cross section of the trench MOSFET in FIG. 3 according to the present invention.
[0021] FIG. 6 is another preferred C 2 -D 2 cross section of the trench MOSFET in FIG. 3 according to the present invention.
[0022] FIG. 7 is another preferred C 2 -D 2 cross section of the trench MOSFET in FIG. 3 according to the present invention.
[0023] FIG. 8 is another top view of a trench MOSFET according to the present invention.
[0024] FIG. 9A˜9I are a serial of cross-sectional views for showing the processing steps for fabricating the trench MOSFET with A 2 -B 2 cross section as FIG. 5A and C 2 -D 2 cross section as FIG. 7
[0025] FIG. 10 is a cross-sectional view for showing an alternative step during fabrication process in FIG. 9F .
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0026] Please refer to FIG. 4A and FIG. 4B for a preferred A 2 -B 2 cross section and C 2 -D 2 cross section of the trench MOSFET in FIG. 3 which shows a plurality of substantial square closed cells with split trenched gates. In FIG. 4A , an N-channel trench MOSFET is formed on an N+ substrate 200 supporting an N epitaxial layer 202 . A plurality of gate trenches 203 are formed within the N epitaxial layer 202 and padded with a gate oxide layer 204 along inner surface. Onto the gate oxide layer 204 , A doped poly-silicon layer 205 is deposited filling within the gate trenches 203 to form a plurality of trenched gates for the N-channel trench MOSFET. A plurality of P body regions 206 in upper portion of the N epitaxial layer 202 surround the trenched gates and encompass n+ source regions 207 near top surface of the N epitaxial layer 202 . A tungsten plug 208 padded with a barrier metal layer of Ti/TiN or Co/TiN is formed filling a contact trench 209 with slope sidewalls to function as a trenched source-body contact which penetrates through an insulation layer 210 , the n+ source region 207 and extending into the P body region 206 to connect the n+ source region 207 and the P body region 206 and connects to a source metal 211 of Al alloys overlying a layer of Ti or Ti/TiN. According to the present invention, each the n+ source region 207 has a Gaussian distribution doping profile from sidewalls of the contact trench 209 to adjacent channel regions near the trenched gates. Within the P body region 206 , a p+ ohmic body doped region 212 is formed surrounding bottom and sidewalls of each the contact trench 209 underneath the n+ source region 207 .
[0027] FIG. 4B shows the trenched gates intersection area in cell corner which comprises a gate trench 203 ′ padded by the gate oxide layer 204 along inner surface. The trenched gates intersection area further comprises split trenched gates of the doped poly-silicon 205 formed along sidewalls of the gate trench 203 ′. The insulation layer 210 described above also extends between the split trenched gates with a thermal oxide layer 213 ′ underneath in center portion of the trenched gates intersection area. Meanwhile, between the split trenched gates 205 and the insulation layer 210 , there is another thermal oxide layer 213 along sidewall of the split trenched gates, wherein the thermal oxide layer 213 ′ is thicker than the gate oxide 204 because the thermal oxide layer 213 ′ also comprises the gate oxide layer 204 along trench bottom. Because the center portion of the trenched gates intersection area comprises the thermal oxide layer 213 ′ not doped poly-silicon, Qgd 1 of the N-channel trench MOSFET is obviously reduced compared to FIG. 2A , as illustrated in FIG. 4B .
[0028] Please refer to FIG. 5A and FIG. 5B for another preferred A 2 -B 2 cross section and C 2 -D 2 cross section of the trench MOSFET in FIG. 3 . In FIG. 5A , the N-channel trench MOSFET has a similar structure to FIG. 4A except that, there is an N* on-resistance reduction doped region 314 formed within the N epitaxial layer 302 and surrounding bottom of each the trenched gate to further reduce Qgd of the N-channel trench MOSFET wherein the N* on-resistance reduction doped region 314 has a higher doping concentration than the N epitaxial layer 302 . In FIG. 5B , there is also an additional N* on-resistance reduction doped region 314 formed within the N epitaxial layer 302 and surrounding bottom of the trenched gates intersection area compared to FIG. 4B .
[0029] Please refer to FIG. 6 for another preferred C 2 -D 2 cross section of the trench MOSFET in FIG. 3 . Compared to FIG. 5B , the trenched gates intersection area in FIG. 6 has an additional P* gate-drain charge reduction doped area 414 ′ formed within the N epitaxial layer 402 and surrounding bottom of the trenched gates intersection area to further reduce Qgd 1 .
[0030] Please refer to FIG. 7 for another preferred C 2 -D 2 cross section of the trench MOSFET in FIG. 3 . Compared to FIG. 6 , the insulation layer 510 in FIG. 7 has a void 515 existing between the split trenched gates of doped poly-silicon layer 505 due to the insulation layer 510 not able to fill up the narrow area between the split trenched gates during fabrication process.
[0031] Please refer to FIG. 8 for another top view of the trench MOSFET according to this invention. Compared to FIG. 3 , except for the implementation of the P* gate-drain charge reduction doped region, the trench MOSFET in FIG. 8 has rounded trenched gate corners and circular trenched source-body contact to further save die area.
[0032] Referring to FIGS. 9A to 9I for a series of cross-sectional views to illustrate the processing steps for manufacturing a trench MOSFET with C 2 -D 2 cross sectional as FIG. 7 and A 2 -B 2 cross section as FIG. 5A . In FIG. 9A , a trench mask (not shown) is applied to open a plurality of gate trenches 503 by dry silicon etching process in an N epitaxial layer 502 supported on an N+ substrate 500 , wherein the gate trench located in gate trenches intersection area is illustrated as 503 ′, as shown in C 2 -D 2 cross section. Then, a sacrificial oxide layer (not shown) is grown and removed to repair the sidewall surface of the gate trenches 503 and 503 ′ damaged by the trench etching process. Next, a screen oxide 516 is grown for preventing ion implantation damage. Then an Arsenic ion implantation is carried out to form N* on-resistance reduction region 514 surrounding bottom of each gate trench 503 and 503 ′ with higher doping concentration than the N epitaxial layer 502 .
[0033] In FIG. 9B , the screen oxide 516 is first removed and a gate oxide layer 504 is deposited or grown overlying inner surface of the gate trenches 503 and 503 ′ and also onto top surface of the N epitaxial layer 502 . After that, the gate trenches 503 and 503 ′ are filled with a doped poly-silicon layer 505 followed by dry etching or CMP (Chemical Mechanical Polishing) of the doped poly-silicon layer 505 to remove it from above the top of the gate trenches and further to a pre-determined depth, forming a plurality of trenched gates for the trench MOSFET.
[0034] In FIG. 9C , a Boron ion implantation is carried out to form a P type implantation area 517 in upper portion of the N epitaxial layer 502 . Next, after applying a poly mask 518 , a dry poly etching is carried out to form a poly hole 519 defined by the poly mask 518 in center portion of the doped poly-silicon layer 505 in the gate trench 503 ′. The poly hole 519 is extending from top surface of the doped poly-silicon layer 505 in the gate trench 503 ′ to expose center bottom of the gate trench 503 ′, therefore implementing split trenched gates structure in trenched gates intersection area in cell corner as shown in C 2 -D 2 cross section.
[0035] In FIG. 9D , after removing the poly mask 518 , a P type dopant ion implantation is carried out to form a P* gate-drain charge reduction doped region 520 in upper portion of the P type implantation area 517 , as well as in the trench bottom underneath the poly hole 519 .
[0036] In FIG. 9E , a step of body diffusion is performed to form a plurality of P body regions 506 extending between the trenched gates, as well as a P* gate-drain charge reduction doped region 514 ′ underneath the trenched gates intersection area and surrounding bottom of the split trenched gates. Then, a step of thermal oxidation is carried out in the body diffusion to form a thermal oxide layer along sidewall of the split trenched gates and covering top surface of the plurality of trenched gates and the N epitaxial layer 502 . Meanwhile, at bottom of the poly hole 519 , the thermal oxidation also increases thickness of the gate oxide 504 on center portion of the trench bottom to form another thermal oxide layer 513 ′. Obviously, the thermal oxide layer 513 ′ is thicker than the gate oxide 504 .
[0037] In FIG. 9F , an insulation layer 510 comprising BPSG (Boron Phosphorus Silicon Glass) and undoped TEOS (Tetraethyl Orthosilicate) is deposited covering the first thermal oxide layer 513 and extending between the split trenched gates to fill the poly hole and reach the second thermal oxide layer 513 ′. During the insulation layer deposition process, a void 515 is induced due to the insulation layer 510 not able to fill up the narrow poly hole area between the split trenched gates. Then, a contact mask (not shown) is applied onto the insulation layer 510 to define location of contact trench. Next, a dry oxide etching is performed to removing the insulation layer and the thermal oxide layer from where according to the contact mask to form a plurality of contact openings 520 with slope sidewalls. Then, an n+ source ion implantation and diffusion is carried out through the contact openings 520 to form n+ source regions 507 in upper portion of the P body regions 506 with a Gaussian distribution profile from edge of the contact openings 520 to channel regions near the trenched gates.
[0038] In FIG. 9G , the contact openings 520 are etched to further extending through the n+ source regions 507 and into the P body regions 506 with slope sidewalls by dry Silicon etching to form a plurality of contact trenches 509 .
[0039] In FIG. 9H , a step of P type dopant BF 2 ion implantation is carried out to form a p+ ohmic body doped region 512 within the P body region 506 and surrounding bottom and sidewalls of each the contact trench 509 underneath the n+ source regions 507 . Then, a RTA (Rapid Thermal Annealing) is performed to activate the P type dopant in the p+ ohmic body doped region 512 .
[0040] In FIG. 9I , a layer of Ti/TiN 521 is first deposited along inner surface of each the contact trench 509 and top surface of the insulation layer 510 to function as barrier metal layer, then, tungsten metal is deposited onto the barrier layer and filling into the contact trench 509 . After that, the tungsten metal and the barrier metal layer is etched back to be left within the contact trench 509 to act as tungsten plug 508 . Next, a layer of Al alloys overlying a Ti or Ti/TiN layer, or Ti/Ni/Ag is deposited onto the tungsten plug 508 and the insulation layer 510 to act as a source metal 511 which connected to the n+ source regions 507 and the P body regions 506 via the tungsten plug 508 .
[0041] FIG. 10 is a cross-sectional view for showing an alternative step during fabricating the trench MOSFET which is similar with FIG. 9F except that, before the N type dopant ion implantation, a thin screen oxide layer 525 is deposited along inner surface of the contact opening 520 to minimize ion implantation damage. The screen oxide layer 525 is then removed before the dry Silicon etching as in FIG. 9G .
[0042] Although the present invention has been described in terms of the presently preferred embodiments, it is to be understood that such disclosure is not to be interpreted as limiting. Various alternations and modifications will no doubt become apparent to those skilled in the art after reading the above disclosure. Accordingly, it is intended that the appended claims be interpreted as covering all alternations and modifications as fall within the true spirit and scope of the invention. | A trench MOSFET with closed cells having split trenched gates structure in trenched gates intersection area in cell corner is disclosed. The invented split trenched gates structure comprises an insulation layer between said split trenched gates with thick thermal oxide layer in center portion of the trenched gates intersection area, therefore further reducing Qgd of the trench MOSFET without increasing additional Rds. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. provisional application Ser. No. 60/972,377, filed on Sep. 14, 2007, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to particle acceleration devices and methods thereof. More particularly, the invention relates to particle acceleration devices and methods used for measuring properties of subterranean formations such as in borehole logging or wellbore applications.
[0004] 2. Background of the Invention
[0005] Nuclear borehole logging measurements typically employ one or more unstable radio-chemical isotopes such as 137 Cs or AmBe to generate fixed-energy gamma or neutron radiation (logging sources). Due to the requirements of the oil industry, such sources are of extremely high intensity and radio-activity, often exceeding 2 Ci for 137 Cs and 20 Ci for AmBe. As such, their deployment in oilfields worldwide is strictly controlled and regulated. The use of such sources forces the well-logging industry to manage great safety and security risks.
[0006] Alternative, “source-less” methods exist such as X-ray tubes, betatrons and minitrons (see e.g., U.S. Pat. Nos. 5,122,662 and 5,293,410 by F. Chen et al.). X-ray tubes are essentially electro-static accelerators and as such they are limited to energies of a few 100 KeV that can be reached with DC electric fields. Betatrons are in principle capable to reach very high energies however it remains a challenge to do so in the confined space of a logging tool. Minitrons are powerful, extremely compact neutron sources, however reaching further increases in output and lifetime remains extremely challenging. Linear accelerators can be utilized to accelerate electrons onto a radiator target to produce X-rays or to accelerate protons or other nuclei onto nuclear targets (e.g., Be, Li) to produce neutrons. Linear acceleration schemes based on traditional RF acceleration from a pillbox type microwave cavity (normally conducting pill box cavity) are notoriously difficult to scale for borehole applications, given the excessive power consumption, tool length and tool weight. As such they have never been employed in the oilfield.
[0007] An acceleration method is disclosed that relates to photonic band gap cavities (PBG cavity). A suitably designed resonator based on a PBG structure confines only the desired oscillating modes of electromagnetic fields, such as those required for particle acceleration. This property of a PBG cavity is well described in the scientific literature, including, for example J. D. Joannopoulos, R. D. Meade, and J. N. Winn, Photonic Crystals: Molding the Flow of Light (Princeton, N.J.: Princeton University Press, 1995).
[0008] With a PRG resonator operating at microwave frequencies in the GHz region, the RF power coupled externally via—e.g.—a coaxial loop or a wave-guide, can be concentrated in a very small volume providing a localized accelerating gradient. Mode selection inside the cavity ensures that only the wanted acceleration modes are present. This allows for an efficient use of RF power in an ideal compact geometry where wall losses are greatly reduced. The underlying principle of PBG cavity is universal and as such PBG cavities can operate in a broad range of frequencies.
[0009] A PBG-based electro-magnetic resonator (a cavity) consists of a symmetrical arrangement of plates and rods. An inverse structure with a symmetrical arrangement of cylindrical holes bored into a solid template may also be used. In either case the periodic structure is designed in such a way that the propagation of electro-magnetic waves in certain TE and/or TM modes in a given frequency range (the band-gap) is effectively forbidden. This feature depends principally on the boundary conditions and the geometry of the cavity.
[0010] A suitable PBG cavity would consist of symmetric plate-rod structure. Such a structure would also contain one or more introduced defects such as a missing or partially withdrawn rod. The volume around the defect is open to the electromagnetic mode whose propagation is elsewhere blocked by the band gap. In other words, the modes in the band gap are confined to the rod structure only and are by their very nature discrete. By introducing a defect while still preserving the symmetry properties of the resonator we have access to the confined, mode-selected fields that would otherwise be confined inside the rods. These fields effectively are those of a resonant cavity. Similarly, when the cavity consists of holes: the electro-magnetic modes may be confined to the holes.
[0011] U.S. Pat. No. 6,801,107B2 by Temkin et al. describes a PBG cavity that is suitable for frequency-filtering in the microwave regime. In particular, the Temkin device relates to vacuum electron devices that comprises a Photonic Band Cap (PBG) structure (or cavity) capable of overmoded operation, as well single mode operation. One distinct advantage of PBG cavities used for particle acceleration relative to prior art is that practically all undesired higher-order electromagnetic modes are not confined by the defect structure and therefore leak away with minimal effect on the electrons or ions in the beam.
SUMMARY OF THE INVENTION
[0012] At least one embodiment of the particle acceleration scheme is disclosed for use in subterranean formations such as for borehole and well-logging applications. In this scheme, particle beams of electrons or ions can be accelerated by the localized electric fields oscillating at high frequencies in resonant photonic band gap cavities. By employing one or multiple evacuated cavities structures, particle beams confined to a vacuum system can be accelerated up to energies of several MeV. Such energetic particle beam can then directed toward one or more targets of many possible materials, to generate gamma-ray or neutron radiation fields. With this device, it is possible to develop a compact, efficient borehole accelerator tool with which it becomes possible to perform a variety of well-logging measurements while overcoming the operational and security risks associated with the high-activity radio-chemical gamma or neutron sources typically used in the well-logging industry. For the purposes of this invention, borehole logging can be considered the science dedicated to measurements of rock or reservoir geophysical properties in subsurface wells.
[0013] An advantage of many of the schemes disclosed in this invention is improved power efficiency: power consumption is a pressing demand for borehole tools. It is estimated that, near-term, only a few kW of average power will be available in a wire-line configuration. However only a fraction of that power will be available to the accelerator tool and in addition the required high microwave power levels must be sustained up to very high ambient temperatures. PBG electro-magnetic cavities efficiently confine the accelerating electrical field to a small-volume region, resulting in less stored energy for the same accelerator gradient and smaller power losses.
[0014] A further advantage of the scheme according to the invention is that the cavity comprising dielectric rods with a low loss factor gives higher Q-factors compared to a cavity with metallic rods such as that of U.S. Pat. No. 6,801,107B2 by Temkin et al. A high cavity quality factor results in a further reduction of input power requirements. This increase in efficiency is important for borehole applications for the reasons given above.
[0015] According to another embodiment of the invention, another advantage is that an improved Q-factor may also be obtained in a cavity structure with no end plates or by providing axial confinement by means of an end-cap structure or end plate structure (layered or monolithic) made of dielectric and/or metallic materials which may include hollow or evacuated layers.
[0016] A further advantage of the scheme according to the invention is its compactness: by utilizing PBG resonators with small losses relative to pill-box cavities, one can reduce the tool length and weight. The optimal down-hole tool will preferably fit in a standard length tool section (20 feet or less) and will be manned by a standard crew without requiring the use of cranes for lifting. At 10 GHz, the required PBG cavity diameter is of only a few cm.
[0017] Advantageously, the PBG resonator confines only the desired cavity modes in the region of the particle beam. Other modes are free to propagate and will quickly damp at the walls. This provides suppression of unwanted (higher-order) modes that can “blow up” or defocus the beam including wakefields. Wakefields excited by a charged beam traversing a classical pill-box RF cavity are a strong function of the operating frequency (˜ω 3 ) and would otherwise limit operation at very high frequencies. On the other hand high-frequency operation is desired since it brings about a compact size and improves power efficiency.
[0018] High frequency operation in the GHz region is also advantageous since it can ultimately provide a nearly continuous particle beam with a near unity duty factor. The duty factor and time structure of the beam critically affect the ability to perform measurements such as density logging in the preferred single-photon counting mode.
[0019] A power-efficient linear acceleration scheme such as the one proposed can also be advantageously utilized to provide a beam with lower energy but higher average current, up to a few 100 uA. The resulting radiation fields can have much higher intensity than those of conventional logging source sand one can therefore achieve better accuracy or reduced counting time for nuclear well logging measurements.
[0020] Furthermore, high electron energies achievable with a PBG accelerator result in an improved bremsstrahlung yield from a thick high-Z target, resulting in a higher flux of photons available.
[0021] Photons with energies higher than those from conventional logging sources and/or more intense photon fluxes are more penetrating and as such they have an increased depth-of-investigation for density logging kind of measurements, including logging behind casing.
[0022] An accelerator beam is an intrinsically safe source of radiation fields as the radiation output can be entirely controlled electronically.
[0023] Some of the particle acceleration schemes disclosed according to the invention also provide optimized vacuum packaging with open PBG structures in a single vacuum enclosure (super-cells or infinite cells). This allows for better pumping and also better thermal insulation.
[0024] The invention also provides improved stability of the cavity tune as a function of temperature: detuning effects in a pillbox RF cavity would naturally occur in a borehole due to local cavity heating such heating due to power losses as well as increased ambient temperatures due to the geo-thermal gradient. Changes in temperature result in a change of cavity dimensions and thus a cavity tune shift. Reduced ohmic losses in PBG resonators of type described above result in less overall heating. In addition, improved thermal insulation can be obtained with open PBG cavity structures in a common vacuum envelope, and/or dielectric materials may be used with smaller coefficient of thermal. Finally, the cavity frequency in a PBG resonator is a function of the ratio of rod spacing to rod diameter, which is less sensitive to thermal effects than just the cavity radius in a pill-box cavity.
[0025] Advantageously, the PBG structure can also be designed to confine dipole, quadrupole or other multipolarity electro-magnetic modes around the defect region. This could allow for beam steering or focusing.
[0026] The PBG technology is scalable and can also be employed to confine electric fields at much smaller wavelengths such as those associated with optical sources including diode, semiconductor or fiber lasers, while still providing the many benefits mentioned above relevant to down-hole logging. A suitable accelerator mode can be supported by a photonic “holey” fiber or MEMS structure excited by a laser beam.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is an example of a PBG resonant cavity structure, according to an embodiment of the invention; and
[0028] FIG. 2A and FIG. 2B represent mode maps of a resonant PBG cavity structure showing confinement of the desired TM 01 mode around a defect in the center, according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] A particle accelerator scheme is disclosed for example in the implementation to borehole and well-logging applications. In this scheme, particle beams of highly relativistic electrons or ions are created by passage through one or multiple acceleration cells, some or all of which may be realized with a photonic band-gap cavity. Each cavity acts as a means to couple a high electric field to particles travelling in a vacuum enclosure inside a geometrically constrained logging tool. In particular, for a particle accelerator cavity to be used in a subterranean environment, e.g., down-hole tool, a set of optimizations is required that is over and above the stated prior art. For example, the PBG geometry and materials in terms of RF power losses must be optimised, as well as the opening for the beam and coupling to external RF sources. New implementations become possible when utilizing several PBG cavities, similar to the more conventional approaches based on pill-box type of EM resonators.
[0030] A suitable PBG cavity may comprise two or more endplates (e.g., two or more end-caps) connected by symmetrically spaced rods. One particularly advantageous configuration is the triangular lattice (see FIG. 1 ). The end-plates (e.g., end-caps) of the cavity are typically parallel to each other and may have a round or any other cross section. The end-plates (e.g., end-caps) of the cavity may be tapered or shaped in order to more efficiently focus the accelerating field. The rods may have circular, elliptic or other cross-sections, including varying cross sections. In addition, the volume between the end-plates (e.g., end-caps) and including the inner rods of a PBG may be fully or partially enclosed by exterior walls or enclosed in a separate vacuum chamber superstructure.
[0031] By choosing the correct geometrical arrangement, materials and coupling scheme one can create a band-gap or a range of frequency for which no EM-mode propagation is possible inside the cavity and fields are confined at the rods. When at least one of the rods is missing, one purposedly introduces a defect in the resonator structure. This creates one or more regions where high power electromagnetic radiation is localized (see FIGS. 2 a and 2 b ). One may also create defects using special geometry rods, such a hollow rods, split-rods, partially withdrawn rods or rods with different geometries. Further, FIG. 2 b shows as aspect of the invention, e.g., the dipole mode.
[0032] With this arrangement one can, e.g., create a longitudinal electric field (TM01 mode), see FIG. 2 a ) suitable for particle acceleration in the region where the particle beam is to traverse the cavity. The band-gap mode frequencies depend on rod spacing, diameter and shape, as well as rod placement and overall cavity geometry. At 10 GHz frequencies, this corresponds to spacing between the rods in the cm scale for rod diameters of a few mm. Generally, operating at higher frequencies will involve smaller distances and diameters.
[0033] The plates, rods and walls, or parts thereof, may consist of metallic conductors, dielectric insulators or coated metals or insulators, or a combination of metallic and dielectric elements. Use of rods or plates (e.g., end-caps) made of dielectric material with very low loss factors in the frequency region of interest (10's of GHz) such as Alumina (Al2O3) or single crystalline sapphire minimizes losses and improves the resonant property of the cavity (quality factor or Q-factor). This in turn provides a more power efficient design. The overall Q-factor in a cavity is limited by its intrinsic Q-factor, before dielectric or ohmic losses, which is typically very high (Q˜up to 10 6 ). By minimizing ohmic losses the Q-factor approaches its high intrinsic value and the power consumption is optimized. Since the amount of RF power available in a down-hole tool is limited, by non-limiting example, to approximately a few kW (average power) it is preferable to keep losses to a minimum. Increased power deliverable to the cavity allows for increased beam energy and/or beam intensity.
[0034] To optimise losses the rods may be of different materials, and the cavity may be partially or fully loaded with a dielectric medium. Hollow rods with cooling help reduce the dielectric loss-tangent. Such fine tuning could be also advantageous to better shape the electric field and/or improve mode selection inside the cavity, and finally to optimize the cavity dimensions and operating frequency with respect to the constraints typical of borehole tools. The use of absorbing material on the cavity walls helps to further damp all of the unwanted delocalized oscillation modes outside the band-gap.
[0035] A perfect band-gap might not be penetrated from outside. In order to couple the cavity to an external excitation source, some of the rods from the external rows must be removed or partially withdrawn. Alternatively one may use thinner diameter rods. This does not significantly affect the field in the central region, which to first order is shaped by the inner rows of rods, whereas the outer rods provide focussing and confinement of the accelerating mode in the defect region. Coupling to the external source may also be achieved with a coupling loop at the end of a coaxial transmission line, including a balanced transmission line. Alternatively, a specially designed waveguide can be employed.
[0036] At very high operation frequencies an equivalent PBG structure may be manufactured through micro or nano-fabrication (MEMS) techniques. In this case, one may use an optical power source such as a laser, instead of a microwave source.
[0037] In one embodiment, a borehole accelerator comprises of separate cavities, some of which being PBG cavities. The one or more cavity will be part of an evacuated beam line. Each cavity chamber will allow for at least one opening for beam propagation in and out of the cell. For at least one cavity cell, there should one opening for coupling in the external high-frequency power driving the resonator. Alternatively, it is also possible to couple multiple cells together into well-known single travelling or standing wave structure. In each cavity, field gradients up to a few MeV/m are possible, for input power levels of a few kW. Particles in phase relation with the electrical field in each of the acceleration cells will be accelerated to high energies while travelling along the length of the whole accelerator device. The distance between cells will vary in accordance with the speed of the particle beam in each section and the need to maintain phase relation between the electric field and the particle beam.
[0038] In another embodiment, a borehole accelerator structure comprises one or more super-cells. A super-cell comprises multiple PBG cavities inserted in a common vacuum enclosure. Each PBG cavity in a super-cell comprises a pair of plates connected by rods but the end-plates (e.g., end-caps) are now not connected by walls or are only partially connected by walls including walls with openings. This realization allows for easier pumping over the length of the accelerator. Different coupling mechanisms can be used to deliver RF power to the region between the plates defining each PBG cavity, and the particle beam may propagate in between cavity sections through drift regions in vacuum or one may also use irises or diaphragms in between cavities to better optimise the accelerating RF field.
[0039] In yet another embodiment a borehole accelerator structure comprises one “infinite” PBG cavity with no end plates or plates kept at large distance. In this realization, the PBG cavity can be described as two-dimensional and as such one increases the quality of the resonator and minimizes losses at the end plates. In such an extended structure, the longitudinal field will perform one or more full oscillation cycle along the length of the cavity. When at the opposing phase, the field will decelerate the beam. To prevent this, the rods in the region where the field direction is opposing the incoming beam may be shaped in such a way as to diffuse the localized field outside of the beam region and thus over the volume of the vacuum chamber. A section with thinner rods or greater rod spacing would allow the opposing field to be outside of the band-gap and thus “leak out” and be absorbed in the exterior vacuum chamber walls. This configuration may still provide net acceleration with an improved efficiency factor (Q-factor).
[0040] A borehole accelerator can also comprise any combination of the accelerator structures described above. For any such structure, partial recovery of exiting RF power should be possible.
[0041] The source of electrons may consist of a thermo-ionic gun, carbon nanotube emitter or MEMS-based field-emitter. Before entering the high-gradient section of the borehole accelerator, the initial energy of electrons could be raised to the nearly relativistic regime by either electrostatic acceleration (up to a few 100's of kV), acceleration via magnetic induction (such as with a compact betatron) or acceleration of the beam through circulation in other RF cavities, including a conventional microwave cavities. | A particle accelerator device structured and arranged for use in a subterranean environment. The particle accelerator device comprising: one or more resonant Photonic Band Gap (PBG) cavity, the one or more resonant PBG cavity is capable of providing localized, resonant electro-magnetic (EM) fields so as to one of accelerate, focus or steer particle beams of one of a plurality of electrons or a plurality of ions. Further, the particle accelerator device may provide for the one or more resonant PBG cavity to include a geometry and one or more material that is optimized in terms of RF power losses, wherein the optimization provides for a PBG cavity quality factor significantly higher than that of an equivalent normally conducting pill-box cavity. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for joining two skis together so as to avoid more particularly the crossing of the ski tips, while conferring thereon certain degrees of mutual freedom and which can be rapidly and readily positioned on or removed from the ski tips, even with the skis on the feet.
2. Description of the Related Technology
A certain number of devices are already known, which are used either solely at the front of the skis, or at the front and at the rear.
These devices however have drawbacks, from the safety point of view and, from the point of view of facilitating positioning on or removing from the skis.
The document No. FR 79 14681 describes a joining device including a connection rod each end of which is articulated, through a ball joint, in a retention cage previously fixed to the ski.
However, the devices of this kind have a certain number of drawbacks.
The first of them resides in the fact that the spacing given to the two ski tips is unalterable, since it is determined by the length of the connection rod. Consequently, it is not possible to vary this spacing as a function of the snow conditions (packed snow or deep snow), or of the possibilities of the user (beginner or experienced skier) or else of the mode of skiing which this latter desires to practice (cross country or competition skiing). Furthermore, even if the possibility of removing the connecting rod is provided, such removal is not very practical and requires considerable time, and cannot be carried out with the skis on the feet all the more so since said retention cages are necessarly fitted on the curved tips of the skis for they cannot be placed elsewhere.
The document No. DE 1 945 977 relates to a device including connection rods mounted for sliding side by side, so as to form a connection of adjustable length, the junction between the skis taking place by means of a ball joint and cage system fixed to the end of the skis.
This device has the advantage of adjusting the spacing between the ski tips but, although it is removable, it cannot be removed or put back in place by the skier during the skiing session and, in any case, can absolutely not be removed with the skis on the feet.
The document U.S. Pat. No. 3,171,667 describes a device, mounted at the front and at the rear of the skis, comprising a bar which may be of variable length and whose ends are provided with ball joints forcibly fitted in a retention cage made from a resilient material fixed to the upper face of the skis.
This system has the drawbacks of not being able in practice to be removed with the skis on the feet.
In fact, if it is desired to have an efficient connection, the ball joints must be firmly retained, which increases correspondingly the force to be exerted so as to remove them from their housing, this only being possible with great difficulty with the skis on the feet. Furthermore, this device is unaesthetic for the bar remains on one of the two skis. Even if it were completely removed, there would permanently remain on the skis the reception cage of the ball joint which projects, for of appreciable dimensions, which may further modify the mechanical characteristics of the skis.
From the document U.S. Pat. No. 3,357,714 a device is also known for joining two skis together comprising a rigid connection rod, although adaptable in length, articulated at both ends to a connecting piece itself removably fixed to the ski tip by a retractable ball connection during unlocking when it is desired to remove the rod from the skis.
Such a system is fragile and does not withstand shocks. Furthermore, it is not very practical, even difficult or even impossible, to operate because of the risks of seizing or jamming of the sliding sleeve controlling retraction of the balls.
Finally, this system requires the fitting of the device on the internal edge of the skis (column 3, lines 24-25) so as to allow (FIG. 7) an angular position of 90° between the skis and their connecting rod, which results in a disymmetry of the skis causing wear which is twice as fast.
The different embodiments of the connection system between the rod and the skis has however, from different points of view, drawbacks from the safety point of view, from the point of view of the amplitude of the degrees of freedom allowed, of operation and are all fragile and do not withstand shocks because of the rigid connections between the different members.
SUMMARY OF THE INVENTION
The purpose of the invention is precisely to overcome these different drawbacks by providing a device for connecting two skis together with a junction bar of variable length and joined to the ski tips by means adapted for combining, on the one hand, efficiency and safety of the connection and, on the other, the ease and rapidity of fitting a device and removing it from the ski tips, in particular with the skis on the feet, while maintaining as much as possible the aesthetic appearance of the skis as well as the safety of the skier.
For this, the invention provides a device for joining two skis together, readily removable with the skis on the feet, including a connection system comprising a bar of variable length, having at both its ends means for articulating through several degrees of freedom, themselves connected to the ski tips of the skis, by fastening-unfastening means formed by a male part and a female part secured, one to said articulation means and the other to said ski tips, said parts being lockable-unlockable by fitting together then rotation, of a determined amplitude, about an axis perpendicular to the plane of the ski times, of the part secured to said articulation means, characterized in that said articulation means are formed by a piece in the form of a diabolo which is defined as a type of bobbin or spool formed by two opposing cones in an hourglass type configuration or similar structure, made from a resilient material, one at least of the ends of which is mounted for swivelling, and in that the connecting bar is formed of a rod with ends of enlarged diameter sliding freely in cylindrical sleeves connected to one of the ends of said diabolo shaped piece.
Such a device, because of the resilient diabolo shape of the articulation means and instantaneous and automatic adaptation of the length of the connection bar, allows degrees of freedom in all directions, with quite remarkable amplitude, flexibility and comfort.
The flexibility of the connection also allows the device to withstand forces and shocks, without damage, which applied to known devices would inevitably cause breakage thereof.
Other features and advantages will be clear from the following description of embodiments of the invention, which description is given by way of example solely with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematical view in vertical cross section of a ski fitted with a connection device in accordance with the invention;
FIG. 2 is a sectional view through line II--II of the connecting bar (shown as a whole) of the device of FIG. 1;
FIG. 3 is a vertical sectional view through line III--III of the device shown in FIG. 1;
FIG. 4 is a top view of a first embodiment of a part of a device permanently fixed to each ski;
FIG. 5 is a sectional view through line V--V of the device shown in FIG. 4;
FIG. 6 is a partial left hand view in the direction of arrow VI of the device of FIG. 1;
FIG. 7 is a top view of the device of FIG. 6;
FIG. 8 is a sectional view through the line VIII--VIII of the device of FIG. 6;
FIG. 9 is a sectional view through the line IX--IX of the device of FIG. 8;
FIG. 10 is an elevational view of an appropriate tool for controlling rotation of the device of FIG. 6;
FIG. 11 is a top view of the tool of FIG. 10;
FIG. 12 shows in perspective another embodiment of the fixing-unfixing means, and
FIG. 13 shows a part of the device of FIG. 12 permanently fixed to the ski.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The device shown in FIGS. 1 to 3 includes a connecting bar 1 whose ends 2 of enlarged diameter (FIG. 2), in the form of pistons, may freely slide in two cylindrical sleeves 3 each extended laterally and at their lower part by a portion 4 in which a collar 5 freely swivels whose axis 6 is perpendicular both to the axis of bar 1 and to the plane of the ski tip 7, in the center of which the device is mounted.
Collar 5 is integral with a piece 8 in the form of a diabolo, made from a resilient material, of the type forming the feet for the mast of a surfboard, itself secured to a substantially cubic block 9 (FIGS. 6 to 9) itself locked to plate 10 fixed permanently to the upper face of said ski tip 7.
The device is of course symmetrical with respect to the vertical median plane parallel to the two skis 7.
The diabolo shaped piece 8 is fixed to collar 5 and to block 9 by any appropriate means such as threaded rods 11 anchored in piece 8.
Such an assembly makes possible rotation of bar 1 through 360° about axis 6 as well as a rotation of wide amplitude, not only upwards but downwards, in every vertical plane including axis 6, because of the resilience of piece 8 whose axis emerges with said axis 6.
The assembly formed by bar 1, the end sleeves 3 and the articulation means 5, 8 may be very readily and very rapidly fixed to or removed from the ski tip 7, by providing between the ski tip 7 and said articulation means fastening unfastening means formed by the portion 9 integral with said articulation means 5, 8 and by the portion 10 integral with the ski tip 7, these two portions having mutual fitting means of the male and female type with locking by rotation of given amplitude of the mobile portion 9 about axis 6.
In the embodiment shown, the fixed portion 10 permanently fixed to the ski tip is formed (FIGS. 4, 5) of a square, for example a metal plate screwed to the upper face of the ski tip and having on its upper face a projection 12 of small height, of a rectangular shape, whose longitudinal axis is parallel to that of the ski. The projection 12 has, in a side view (FIGS. 5, 6), a general dove tail shape defining two slanted internal sides 13 whose purpose will be described further on.
Projection 12 is intended to be received in a housing 14 provided for this purpose in block 9 and opening through an opening 15 of a generally rectangular shape formed in the lower face of said block 9.
Housing 14 is shaped so as to receive said projection 12 and to make possible a rotation thereof in its housing through an angle for example of 45°, as shown in FIG. 7, where at 16 is shown the axis of the rectangular opening for insertion of projection 12 and, at 17, the axis of the final locked position of the projection in housing 14, this axis 17 being parallel to the longitudinal axis of the ski tip 7.
The housing 14 has two slanting internal opposite faces 18, in correspondance with the slanting faces 13 of projection 12.
For fixing block 9 on plate 10, it is sufficient to present the opening 15 with its axis 16 aligned with a longitudinal axis of the projection 12, to insert the projection in the housing 14 while driving in block 9, then to pivot this latter through 45°, in the desired direction, so as to bring axis 17 parallel to the ski 7.
The rotation of block 9 is very easy and does not require rotation of the assembly 1 to 4 because of the collar 5.
The cooperating slanting faces or ramps 13 and 18, through elastic friction, provide efficient holding in the final position, which may be locked for example by an end of travel snap fit system of known type.
Block 9 may be operated simply by hand, with the skier squatting, who has no need to remove his skis to position the device of the invention or remove it.
For further facilitating operation of the device with the skis on the feet, a special tool may be used in the shape of a fork shown in FIGS. 10 and 11.
This tool has an elongate body 20 with two parallel fingers 21 at one end having on their facing faces two projections 22 adapted for cooperating with two hollows 23 formed in two opposite faces of block 9. These opposite faces, preferably parallel to the axis of the skis, besides the hollows 23 have recesses 24 for receiving and locking the fingers 21 of the fork, facilitating correct positioning and operation of the fork 20, 21. In addition the bottom of said recesses 24 includes depressions 25 (FIG. 9) at the insertion ends of fingers 21 for facilitating their insertion.
The fork tool 20, 21 has a reduced dimension, is light (for example made from a plastic material) and may be readily carried, for example by means of a pin 26 for clipping it in a pocket in the manner of a pen.
The fork tool may have a greater length and comprise for example a telescopic or foldable handle for facilitating storage thereof.
The operation for rotating blocks 9 may also be performed using the tip of one of the skis sticks, which tip may for example be engaged in a hole formed for this purpose at an appropriate position in said blocks 9 or in an extension thereof, this hole having a truncated cone shape and having an axis slanted and turned towards the skier so a to facilitate insertion of the end of the ski tip.
Blocks 9 may also have one or more projections or recesses making possible direct, practical and efficient manual handling operation.
FIGS. 12 and 13 illustrate an embodiment in which the piece 9', similar to piece 9 of the embodiment shown in FIGS. 1 to 10, has a small height and is provided with a horizontal lateral extension 27 giving a ready hand hold for pivoting the assembly 8-9' through 45° with respect to plate 10', similar to plate 10 (permanently fixed to the ski tip not shown).
Plate 10' has on its upper face (FIG. 13) a cross shaped projection 12' similar to projection 12 and cooperating with a housing of the same type as housing 14 (FIG. 7) but adapted for receiving the cross shaped projection 12', formed on the lower face of piece 9'.
As in the embodiment shown in FIGS. 4 to 7, pieces 9', 10' pass from their locked position to their unlocked position by a rotation of 45°.
When the assembly 1 to 9 is removed, there only remains on the skis plates 10, 10' with their projection 12, 12', the assembly (10, 10'; 12, 12') having very modest dimensions and projecting little, so that it is not detrimental to the aesthetic appearance of the skis, nor to their performances or their qualities, nor to the safety of the skier who does not run the risk, for example, of hurting himself in contact with said elements should he fall or when removing his skis.
The elements 12, 12', on the one hand, and 14, on the other, could of course be reversed, by securing projection 12, 12' to piece 9, 9' and by forming the housing 14 in plate 10, 10', which would further have the merit of making the plates 10, 10' smooth and without projections.
Plates 10, 10' may also be in the form of inserts integrated in the mass of the ski tips 7, the upper face of the plates being flush with that of the ski tips.
The spacing between the two skis 7 is of couse adjustable automatically by sliding portions 2 of the bar in sleeves 3, this spacing being variable for example between 60 and 210 mm.
The device of the invention is mounted at the front of the skis between the tip and the shoe binding. A second similar device may be fitted at the rear of the binding. In the embodiment shown, pieces 8 are secured to pieces 9, 9' and the collars 5 swivel in sleeves 3, but the arrangement may just as well be reversed and pieces 8 be secured at their upper end to sleeves 3 and at their lower end to a collar similar to collar 5 and mounted for swivelling in pieces 9, 9'.
The coupling between portions 9, 9' and 10, 10' is of the bayonet type, but other embodiments of this type of connection are of course possible as well as, in a general way, any type of mutual fitting then locking by relative rotation of the members thus assembled.
Of course, the different pieces of the device of the invention may be made from different appropriate materials (plastic material, aluminium, rubber, composition materials, etc. . . . ).
The connecting bar 1, (solid or hollow) may be made from a relatively flexible plastic material allowing the bar to absorb the shocks and vibrations and to give greater flexibility to the device.
Pieces 3, 4 are preferably formed from two molded half shells, assembled together for example by bonding or screwing in a joint plane merging with the vertical plane of symmetry of the assembly 1, 2, 3. Before assembly, the elements internal to the half shells, namely pistons 2 and collar 5, are of course positioned.
It should also be noted that the device of the invention may be readily placed in a waiting position on a single ski, so that in particular mechanical ski lifts can be used without difficulty. For this, one of the ends of the device is removed from one of the skis and fixed to the other ski, which is provided at the appropriate position with a second plate 10, 10' on the projection 12, 12' of which the device is positioned and locked parallel to the ski.
Finally, the invention is obviously not limited to the embodiments shown and described above but covers on the contrary all variants thereof insofar as concerns the nature, shapes and arrangements of the two parts of said means for fixing the articulation means carrying the connecton bar to the ski of removing it therefrom, as well as the nature, shapes and arrangements of the diabolo shaped pieces 8, these latter in particular having a shape removed from that of a diabolo but offering the same possibilities.
It should be noted that the diabolo shaped piece 8 may have fins, made from the same material, as shown in broken lines at 28 in FIG. 3. Piece 8 thus has for example an external cylindrical appearance and withstands better the agressions of the edge of the opposite ski when the device is out of service. | The invention provides a device for joining two skis together, which is readily removable with the skis on the feet, including a connection means formed by a bar of variable length, with fittings at both its ends for articulating through several degrees of freedom, themselves connected to the ski tips by fastening-unfastening fittings formed by a male part and a female part secured to the articulation fitting and the other to the ski tips. The parts are lockable-unlockable by fitting together, then rotation by a particular amplitude, about an axis perpendicular to the plane of the ski tips, of the part secure to the articulation fitting characterized in that the articulation fitting are formed by a piece in the form of a diabolo or similar shape, made from a resilient material, at least one of the ends is mounted for swiveling and in that the connection bar is formed of a rod with ends of enlarged diameter sliding freely in cylindrical sleeves connected to one of the ends of the diabolo shaped piece. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to methods and apparatus for stabilizing the idle speed of spark ignited internal combustion engine.
Prior U.S. Pat. application Ser. No. 044,328 filed May 31, 1979 discloses a method and apparatus for regulating idle speed of a spark ignited internal combustion engine by control of the ignition timing. In particular, the engine therein described is provided with a lean fuel-air mixture, to favorably influence the engine exhaust emission. The loss in the engine torque attributable to the lean mixture is recovered by providing a relatively high air throughout volume. The nominal ignition timing is relatively retarded, and the timing is advanced by a control circuit to stabillize the engine idling speed at a speed which approximates a desired value.
In German patent disclosure No. 2,221,354 there is described another method for stabilizing idle speed upon the occurrence of changes in engine load. In accordance with the disclosure, the ignition timing is advanced to compensate for increased engine load. Also, in order to compensate for the loss in output which results from a nominal retarded ignition timing, the volume of the mixture charge is increased.
German disclosure No. 2,725,460 discloses a governor wherein the volume of mixture provided to the engine is controlled in order to compensate for changes in engine load. A similar control is described in German disclosure No. 2,756,704. That document describes a system for control of air supply as a function of intake vacuum. Idling speed is increased during starting and warmup by an electrically generated control signal.
German disclosure No. 2,715,408 describes an idling speed governor wherein changes in load are compensated by changes in the volume of fuel supplied to the engine.
A characteristic of all of these prior art systems is that speed stabilization is obtained through variation of only a single engine control parameter. Consequently, the parameter must be varied over a range which is large enough to result in poor engine operation for some engine load conditions, or alternatively, full engine speed stabilization cannot be achieved. It is, therefore, an object of the present invention to provide a new and improved method and apparatus for controlling the idle speed of an internal combustion engine.
It is a further object of the invention to provide such an apparatus wherein such control parameter is varied over a predetermined selected range of values to ensure efficient and pollution free operation of the engine.
SUMMARY OF THE INVENTION
In accordance with the invention there is provided a method for operating a spark ignited internal combustion engine to stabilize the actual idle speed to be approximately eqyal to a desired idle speed. In accordance with the invention the engine is supplied with a lean fuel air mixture which has a high air ratio, exceeding the air-ratio corresponding to maximum mean indicated pressure. The ignition timing is controlled within a pair of selected timing limits to bring the actual idle speed toward the desired idle speed. The air ratio of the mixture is also controlled to bring the actual idle speed toward the desired idle speed.
In one embodiment, the air-ratio control is initiated only when the ignition timing reaches one of the limits. In another embodiment the air-ratio control is initiated after an extended time deviation of the actual idle speed from the desired idle speed.
According to the invention there is also provided an apparatus for stabilizing the idle speed of a spark ignited internal combustion engine having control signal operated adjustable ingition timing means and fuel metering means. The apparatus includes a first control device which responds to a first speed signal representing actual engine speed and a second speed signal representing desired engine speed. The first control device generates an ignition timing control signal for operation of the timing means, and for controlling the timing according to the difference between the first and second speed signals within the selected timing limits. There is also provided a second integrating control device, which responds to the timing control signal and the attainment of the timing limits for generating a fuel metering control signal for controlling the fuel metering means to change the air ratio of the mixture supplied to the engine.
In another embodiment the second integrating control device responds directly to the difference between the first and second speed signals, integrating the difference over time to generate a slowly changing fuel metering control signal.
In a preferred embodiment there may be provided a third control device, which responds to the output of the second control device for generating an air volume control signal, which regulates the volume of air supplied to the engine. It is possible to vary nominal values for engine speed, ignition timing, air ratio and air volume according to the actual operating temperature of the engine.
The method in accordance with the invention provides initially for a rapid regulation of the idling speed toward the nominal speed by modification of the ignition angle, i.e., in case of a sped decrease by adjusting the ignition in the direction toward an advance. In the event that the actual idling speed deviates from the desired speed over an extended period or, in the event that on modification of the ignition angle, the predetermined limit values thereof should be attained, a modification of the air ratio will occur for further stabilization of the idling speed. This modification of the air ratio may be subdivided, first, into a modification of the fuel quantity, and second a modification of the air volume supplied. The second "stage", modification of the air volume is initiated through the attainment of predetermined limit values for the modification of the delivered fuel quantity. A rapid response of the control is obtained due to the modification of the ignition angle which becomes effective very rapidly, namely, practically with the next-following ignition pulse. The modification of the air ratio becomes effective less rapidly and provides long-term stabilization so that variation of the ignition angle constituting the first stage remains available for regulating short-term and limited changes in the idling speed.
For a better understanding of the present invention, together with other and further objects, reference is made to the following description taken in conjunction with the accompanying drawings, and its scope will be pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional block diagram illustrating the apparatus of the present invention.
FIG. 2 is a functional block diagram of an alternate embodiment of the present invention.
FIGS. 3, 4 and 5 are graphs plotting mean indicated pressure as functions of air ratio, air volume, and ignition timing for various engine operating conditions.
DESCRIPTION OF THE INVENTION
Two examples of arrangements for carrying out the method in accordance with the invention will be described with reference to the functional block diagrams of FIGS. 1 and 2 and the graphs of FIGS. 3, 4 and 5. The diagrams in FIG. 3 refer to idling stabilization solely through adjustment of the ignition timing which is, the first state of the stabilization method of the present invention and which hereinafter is also designated as digital idling stabilization (DIS). FIG. 4 represents the corresponding diagrams for engine operation according to a method wherein, in addition to DIS there is provided, for speed stabilization, an adjustment of the air ratio through change of the fuel quantity delivered. This stage of adjustment is hereinafter designated as digital idling enrichment (die). In particular, air ratio adjustment serves to ensure, during cold start and warming up the engine an increased mean indicated pressure in the combustion chambers, which yields a higher torque. The higher torque is needed to overcome the higher friction of the engine under cold operating conditions. FIG. 5 contains similar graphs as FIGS. 3 and 4, for engine operation in which, in addition to the adjustment of the ignition timing and air ratio, there is also provided an adjustment of the air quantity delivered to the engine. This third stage of the method in accordane with the invention, on which the examples of embodiments illustrated are based, is designated hereinafter as digital airflow enhancement (DAE).
Referring to FIG. 1, there is shown a block diagram of a control circuit according to the present invention. In the FIG. 1 circuit signals representing the actual engine speed N a and the desired idle speed N d are provided to a comparison circuit 12, which provides an output representing the deviation of the actual idle speed N a from the desired idle speed N d . This deviation signal is provided to a first control device 11 which acts as linear-integrating circuit and provides an output representing ignition timing advance α z which is time-dependent. Thus, the first controller 11 converts the idling speed deviation or error signal into adjustment of the ignition timing within an ignition timing range which is defined by two ignition timing limit values α z max and α z min. These limit values are selected to have values which ensure that timing variation is not great enough to impair engine operation. Thus, they constitute ignition timing operating limits.
The starting value α zO of the ignition timing, which is a pre-selected nominal value, is within the timing range defined by the limit values so that it is possible to make adjustments to the ignition timing towards an advance and towards a delay.
The corresponding nominal values λ O and m LO for air ratio and air volume in the two further stages of the arrangement have been selected in accordance with these considerations.
The ignition timing starting value αz O is delivered to a combining circuit 13 which, depending on the output signals of the first controller 11 proper, delivers adjustment signals for setting the ignition timing α z needed to stabilize the idling speed, to an ignition timing adjusting device in the internal combustion engine 14. Devices of this kind are known in themselves and therefore need not be described here.
The output signals of the combining circuit 13 and the nominal value α zO of the timing advance are provided to the combining circuit 16 and the input of the second control device 15. At the input to second control device 15 there are connected in parallel, for improvement of the regulation dynamics, the three-state threshold circuit 26 with hysteresis characteristics and the delay element 17. Delay element 17 is connected as a feedback around theshold circuit 26 to form a pulse-width modulator.
Deviations from regulation of the idling speed are counteracted initially by adjustment of the ignition timing. Should this not be sufficient, that is, should such large adjustment of the ignition timing be required that the timing reaches one of the limit values, further control of the idling speed is achieved by adjustment of the fuel quantity delivered. In the FIG. 1 embodiment, the fuel quantity adjustment is obtained through changing the length t i of fuel injection pulses. Thereby there is delivered via the second control device 15, which in this case is designed for a selected characteristic of the reciprocal value 1/λ of the air ratio plotted against the time t, the prescribed value is supplied (in form of a correction value) to the succeeding air ratio control circuit 19. Here again a maximal and a minimal threshold value each are provided for the inverse air ratio. Moreover, a nominal value 1/λ for the inverse air ratio is supplied to combining circuit 18, which generates an error for the air ratio. The air ratio control circuit 19, to which this error signal is delivered, supplies a signal determining the injection time t i to the fuel metering device in the internal combustion engine 14. In the example of the embodiment described, the said metering device is the customary fuel injection means. As a matter of principle, it may, of course, also be a carburetor.
As indicated above, the air ratio range has selected values. In the event that further modification of the air ratio should become necessary, namely in the sense of an alternate regulation due to attainment of one of the limit values of the reciprocal value of the air ratio, the control device 20 is actuated by way of the combining circuit 21. Threshold circuit 22 and delay element 23, which operate similar to correponding circuit 16, 26 and 17. Control device 20 provide a control signal which adjusts the air volume m L , within a range defined by the limit values m L max and m L min, as a function of the set air ratio λ or its reciprocal value. The output signal for the air volume, which determines the air volume m L and which is obtained in the combining circuit 24 through comparison with the initial value m LO of the air volume, is delivered to a flap or a valve in the suction system of the internal combustion engine, for example, the throttle valve in the customary intake pipe, or an additional intake air valve.
Thus, as soon as due to an outside moment M w (resistance moment) during idling. There is a decrease of the actual value N a of the speed of the internal combustion engine, in accordance with its time behavior 25. The control apparatus of FIG. 1 will act in three stages of adjustment to cause an increase in the mean pressure p mi in the combustion spaces of the internal combustion engine, which will increase the torque M a produced by the engine to compensate for the disturbance moment M w .
In a preferred embodiment, engine temperature can be taken into account by selecting the values of nominal idle speed N d , nominal ignition timing α zo , nominal air ratio λ o and nominal air volume m LO .sub.. These values can be selected according to the sampled temperature of the engine oil or water from a programmed memory or the like. The combining circuits 12, 13, 16, 18, 21 and 24 are thus provided with temperature-dependent rather than constant nominal values, so that as a result, a speed-controlled warming-up system is obtained.
Analogous considerations also apply to the embodiment shown in FIG. 2. Here, again we find a control device 30, which, in this embodiment is a linear controller, and which is associated with a combining circuit 31 forming the difference between the nominal engine speed N d and the actual engine speed N a . This first control device 30 thus serves to deliver to the internal combustion engine 32 an error signal for adjustment of an ignition timing α z . Thus the control circuit responds to a lower engine speed caused by an addition moment M w by an increase in the ignition timing advance, which increases mean indicated pressure and output torque.
In the FIG. 2 embodiment, the idling speed error signal is delivered by way of the further combining circuit 33 to the second control device 34, which is an integral controller and becomes practically effective only after a given period of time has lapsed. Thus, there occurs here a partial overlap of the operation of the control devices 30 and 34. In the event that in spite of the (rapid) operation of the controller 30, the idle speed deviation should continue for an extended period of time, the (slower) second control circuit 34 becomes effective and causes a modification of the injection timing t i and thereby a corresponding modification of the fuel quantity delivered and the air ratio. As in the example of the embodiment shown in FIG. 1, the modification range of the air ratio and, respectively, its reciprocal value 1/λ is limited by predetermined limit values, and as soon as one of these limit values is attained, the control circuit containing the adjustment drive 35 in addition to the enabling circuit and delay elements becomes effective and brings about a change of the air throughout volume in a manner already described. Thus, a three-stage control is achieved by variation in succeeding the stages of the ignition timing, air ratio and air throughout volume.
For a further understanding of the functioning of the invention, reference is made to the graphs in FIGS. 3, 4 and 5. In each figure the diagram to the left shows the mean indicated pressure p mi in the combustion chambers of the internal combustion engine as a function of the air ratio λ. The middle diagram of each figure shows the dependence of the mean indicated pressure upon the air throughout m L . The diagram to the right in each figure shows the correlation between the mean indicated pressure and the ignition timing advance a z . I all cases idling is assumed.
The working point 1 of the engine shows the currenty customary idling adjustment with a rich mixture and relatively small air throughput. The disadvantage of such adjustments consists in high CO and HC emissions in the exhaust gas. For this reason, and also for reasons of control engineering, the method in accordance with the invention departs from a working point 2 of the internal combustion engine on the downward sloping branch of the air ratio diagram appearing on the left side in the figures, that is, from a lean mixture control. Because of the lean mixture the mean pressure p mi and thereby the torque delivered during idling by the engine drop, the air throughout m L must be increased so that the working point 3 in the diagrams is attained. Control difficulties now arise if the ignition timing setting is selected in the customary manner in accordance with point 3, as indicated in the right-hand diagrams. This ignition angle is so close to the maximum of the indicated mean pressure that an advance of the ignition point would hardly increase the mean pressure. Thus, in order to obtain an improved range of ignition timing control, the nominal setting of the ignition timing is moved to point 4, that is, the ignition is considerably retarded, and the loss in indicated mean pressure resulting therefrom is compensated by a further enlargement of the air throughput to point 5.
When the engine is warm, stabilization of the idling speed can be achieved by adjustment of the ignition timing within the range designated by points 5 and 6. This range is therefore characterized by "DIS" (digital idling stabilization).
FIG. 4 is based on FIG. 3 and concerns the case of creating a deviation of the idling speed due to low engine temperature, such as present during warming up. In this case, a wider margin from the lean operating limit must be ensured through enrichment of the mixture. Therefore, there is provided in addition to the speed control through change of the ignition angle DIS, an increase of the fuel quantity, that is, DIE (digital idling enrichment). The advantage of such a regulation in comparison with a general mixture enrichment during idling may be found in the fact that a mixture enrichment occurs only if a drop in speed actually signals a need for increased fuel delivery.
Whereas the starting point for a DIS is a change in the right-hand diagram of FIGS. 3, 4 and 5, an increase of the indicated mean pressure p mi occurs with DIE through decrease of the air ratio λ, so that each of the left diagrams forms the starting point. Thus the control characteristic of the DIS is enlarged to the hatched area in the diagrams of FIGS. 4 and 5.
FIG. 5 shows the effect of all three steps of the method in accordance with the invention, namely, idling stabilization (DIS) through modification of the ignition angle, idling enrichment (DIE) through modification of the fuel quantity supplied and addition of air (DAE=digital air enhancement), i.e., a change of the air ratio through modification of the air throughput volume m L . As becomes clear from FIG. 5, there is thus obtained a larger control range for influencing the indicated mean pressure p mi without the attainment by the manipulated variable, namely the ignition angle, air ratio and air throughput of any values which would impair the operation of the engine.
In FIG. 5, line 7 shows the required minimum value of the mean indicated pressure when the engine is warm, whereas line 8 shows the corresponding minimum value when the engine temperature is lower. It is clear that shifting the ignition point alone in the direction towards an advance will not be sufficient to cover the mean pressure needed when the internal combustion engine is cold. As already explained with reference to FIG. 1, there can be obtained selected nominal values not only for the ignition angle, but also for the air ratio and the air throughput as a function of temperature, for example, by way of a memory circuit .
The invention offers a method for regulating undesirable idling speed changes, which result from either a change in the engine temperature or from outside moments such as accessories, without the need for the operating parameters of the engine to assume values which are critical for its operation. Application of the method in accordance with the invention is capable of simplifying the automatic starting mechanism customary for vehicle engines.
Those skilled in the art of control circuits will recognize that the control functions herein described can be achieved using various specific circuits. One approach is to use analog circuitry which directly uses signals with voltage proportional to the quantities represented. Another approach is to convert measured quantities, such as engine speed into digital signals and generate the needed control signals digitally using either discrete control elements or a programmed microprocessor. Hybrid arrangements using a combination of digital and analog techniques are also possible.
While there have been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention and it is intended to claim all such embodiments as fall within the true scope o the invention. | Engine idle speed is stabilized by a successive three stage control system which sequentially regulates ignition timing, fuel quantity and air throughput volume. | 5 |
CROSS REFERENCE TO OTHER APPLICATIONS
This is a non-provisional patent specification submitted for an official filing receipt under Code Section 111(a) and which claims priority under Code Section 119 ( ) and 37 C.F.R. Section 1.78(3)from my provisional specification filed Sep. 14, 2000, being given U.S. Serial No. 60/232,509, and having the same title.
BACKGROUND OF THE INVENTION
The art has disclosed a number of devices that qualify as target resetting systems. Hoy U.S. Pat. No. 4,949,988 (1990) is to a multiplicity of upright target assemblies, in which, when a first target is knocked down and held deflected by a latch, then as to a second reset target upon striking same, it moves to unlatch the first knocked down target. However, the inherent target resistance level is not adjustable and requires a minimum level of projectile velocity to be activated.
Rosellen U.S. Pat. No. 5,263,722 (1993) is another resettable target, but with the single reset target being aligned diametrically opposite from the main target array. Moreover, the latching/reset linkages are quite complex (compare FIGS. 5 / 6 ), also being gravity dependent and operable only in the mode depicted.
Estrella U.S. Pat. No. 5,324,043 (1994) is another target resetting system, involving a racheting system and gears, requiring the target mounting shaft to be rotated with the assistance of lever arms (compare FIGS. 2 / 4 ), it is depicted as in extreme complexity of the ratcheting and reset devices.
It is therefore a principal object of the present invention to provide a portable target resetting device in which the array of targets, including the reset target, are substantially located on the same plane, and which device can also operate in the inverted position, as well, for safety purposes.
Another object of the present invention is to provide a target array in which the effecting projectile force and/or target distance can be varied, to one which is adequate for target deflection, allowing a range of projectile sizes usable with a single target array.
Still another object of the present invention is to provide a resettable target array with a uncomplicated linkage means, which latches a hit target and sets one or all of them upon striking of the single reset control target means.
Yet another object of the invention is to provide a resettable target array in which any number of targets can be deflected, permitting a reset action to be triggered, should a shooter have expended his clip without deflecting all his targets.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a schematic front (display side) elevation view of how the resettable target array of the present invention appears to an approaching practice shooter;
FIG. 2 is an above angle, perspective view of the target array system depicting their underlying elongate support and action shafts, and their associated helical spring rotational biasing mechanisms;
FIG. 3 is a schematic illustration depicting the use of the target array at the point where the shooter is now striking the reset target to bring the entire array target upright;
FIG. 4 is a top plan view of the present system depicting the targets array, all being upright and of the associated pair of torsion-biased elongate bars and their interconnecting levers;
FIG. 5 is a vertical sectional view of typical target plate depicting its pivoted target support means and the associated deflecting and latching mechanism;
FIG. 6 is a vertical sectional view of the resetting target plate depicting the pivotable target support and the associated transient deflection and array resetting mechanism;
FIG. 7 is a broken out, reverse side, perspective view of the one of the intermediate targets, depicting its deflection and latching mechanism, which corresponds to the view FIG. 5;
FIG. 8 is a broken away, perspective view of the reverse view of the present array, depicting two of the targets in the deflected mode, but capable of reset; and,
FIG. 9 is a broken out, reverse side, perspective view of the one terminal end of the device frame which supports the reset target, along with its discrete deflection, and array reset linkage, and corresponds to view of FIG. 6; and
FIG. 10 is a broken away, enlarged top side view of a segment of the rearward mechanism of FIG. 5 (rotated 180 degrees) depicting the lever return arresting device for targets 1 - 5 .
SUMMARY OF THE INVENTION
According to the invention, there is provided a multiple target apparatus having: an array of discrete target plates arrayed linearly on and mounted pivotally upon a horizontal elongate rigid first rod; a plurality of first torsion-providing means encasing the first rod substantially along its length, and which first means is adapted to bias a first target to rotate in a first arcuate direction that normally maintains the associated target in an upright mode; a spaced-apart, horizontal elongate second rod, being substantially parallel with the first elongate rod, has a second torsion-providing means, encasing the second rod substantially along its length, and which second torsion means is adapted to bias rotation of said second rod in the opposing arcuate direction to that of the first rod; at least one target deflection and arrest means is functionally interconnecting the first and second rods, which said arrest means comprising a depending first arm tied to the pivotal axis of the first target plate; a rigid first lever spanning the space between the second elongate rod and the depending first arm, and with lever end being slightly offset from that first arm at the depending first longitudinal end thereof; a first detent means secured proximal to the free longitudinal end of the first lever means and adapted to contact and arrest the counter-rotation of the depending end of the first arm of the first target plate; the first lever means also being tied at the other longitudinal end thereof to the second rod; a single target deflection and array reset means functionally associated with a second target plate, comprising: a second lever means spanning the space between the second elongate rod and the depending second arm; a second detent means secured flush with the free longitudinal end of the second lever means; the second arm, which is adapted to make transient contact with the somewhat longer, second arm of the second target reset means, such that when the second target plate of the array reset means is deflected backwardly by a projectile impact, then the second arm rotates clockwise and depresses both the second lever means and its associated second rod, and thus concurrently depresses the remote, first lever means, inter alia, thereby spacing apart the first detent means and the associated depending first arm, allowing the first torsion means of the first rod to rotate both the associated first target from an arrested deflection position back to the upright position, as well as rotation to the upright of the second target. In a preferred embodiment, the first arcuate direction of the first rod is the one that rotates an associated target means such that the unlatched first target rotates in a first arcuate direction from an inclined deflection mode to an upright mode, whereby the second torsion-providing means rotates the second rod reciprocally in the opposite arcuate direction, returning each of the first and second lever means to a non-arrest mode for the associated depending arms thereof of each.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawing, and to FIG. 1 in particular, there is seen a schematic view of the display facade of a resettable target array of the present invention, comprising an elongate rectangular frame, generally 20 , with paired sets of stilt-like support legs, 22 L/M/R, and an exemplary, substantially linear, array of six targets, 26 A-F, with each face plate numbered 1 to 5 , all being independently deflectable by a bullet, and each retainable in that back deflection mode (FIG. 2 ). However, the sixth end target, 26 F (letter R inscribed), provides a single deflectable and array reset means for the depicted array in a manner to be described.
In the downward angle, perspective view of FIG. 2, it will be seen that each target bottom arcuate edge (periphery), is mounted upon an elongate first support rod 28 , which rod is supported at its opposing longitudinal ends upon the transverse elements, 30 L/R, within the lower end brackets, 32 L/R, of rectangular frame 20 , with the targets themselves being rotatable upon a discrete collar encasing the rod segments.
First rod 28 is encased through most of its linear length by a set of like helical springs, 34 A/F, each of which are operatively connected to one of the plate-like targets, 26 A/F, themselves. For example, left end, coiled spring 34 A is linked to left hand target 26 A (# 1 ), and will then serve to continuously bias that specific target to be in the erect mode, as is depicted, until a projectile (not seen) provides the kinetic energy needed to deflect target 26 A arcuately backward (See FIG. 3 ). An associated mechanism, to be described, then arrests the deflected target 26 A in the “knock-down mode” so it is mostly out of line of sight until a later event, also to be described, which event will reset target 26 A, and any, or all, of the other numbered deflected targets 26 A/E, deflected by hitting target “R”, the reset target.
Behind each of the targets is a separate rigid means, such as lever 36 A, the free end, 37 A, of which (FIG. 5) functionally contacts the opposing targets in a manner, to be described. Each of transverse levers, 36 A/F, are pinned at their rearward longitudinal ends to a second elongate rod 38 , which is spaced apart from, and parallel to, the first rod 28 , which is also similarly mounted at its longitudinal ends, rotatably to members 30 L/R frame 20 . As with first rod, a plurality of helical springs, 40 A/F, encase rearward rod 38 , and they serve to bias that rod, and its attached levers, 36 A/E, to rotate in an upward (clockwise) direction, whereby the lever free ends, 37 A/E, will make contact with the arms, 46 A/E, depending from target support collar, 44 A/E (FIG. 5 ).
FIG. 3 depicts schematically a target user directing a bullet, at the reset target, 26 F, after the first five targets have been deflected and arrested in the deflected position. The transient deflection of target 26 F will serve to reset the entire array by means, to be described.
In the top plan view of FIG. 4, the interconnection of each of the upright targets 26 A to 26 F, to the spaced apart, torsionally-biased rotatable elongate bars, 28 and 38 , and the spanning levers, 36 A to 36 F, which are each pinned spaced apart to the rearward rod 38 , are better seen.
Aligned along second rod 38 , on the upper perimeter thereof, and a spaced apart set of arrest elements 39 A/E located proximal to each lever 36 A/E. They serve to arrest the rotation upwardly of each lever, while it is subjected to the second set of torsional bearing means 40 A/F.
Averting to the vertical cross sectional view of FIG. 5, there is depicted how any single one, or all, of the deflectable targets, 1 to 5 , appear after their deflection by a projectile (not 20 seen). Each target support collar, generally 44 A, is provided with a depending rigid arm 46 A. Detent 52 A is mounted proximal to, but spaced apart from, the opposing free longitudinal end of spanning lever 36 A. The upward bias of lever arm 36 A (induced by associated rearward helical spring 40 A) has been interrupted by the clockwise rotation (a projectile impact on target 26 A), which then engages detent 52 A located on spanning lever end 37 A, to prevent the return of target 26 A to the vertically erect position of FIG. 1 . This depicted deflection for the target 26 A will remain in the arrest mode, until some later event (like a FIG. 3 firing), which breaks the seating contact, at least momentarily, such would then permit the torsion-induced bias of helix 34 A on the target support assembly 44 A to rotate target 26 A back to the upright position (seen in phantom).
When the “knockdown” of reset target 26 F occurs (FIG. 3 ), the downward deflection of ganged lever 36 F rolls up on 52 F, and rotates shaft 38 counter-clockwise. The shaft 38 rotation concurrently rotates ganged levers 36 A/E, releasing them, so that each of the deflected targets 26 A/E, will rotate back to the erect mode. At this moment, helical spring 34 F rotates also resets target 26 F back to the erect mode.
In the vertical cross sectional view of FIG. 6, the differing free end configuration, namely of edge-mounted detent, 52 F, on spanning lever 36 F is depicted. Only depending arm 46 F has on its terminal end, a cylindrical bar 54 F, so that the depending end 52 F of depending arm 46 F is not arrested by the arcuate movement bias inherent in lever 36 F. Depending arm 46 F itself, being somewhat longer than all of the other arms, like 46 A, such that when target 26 F is deflected backwardly, spanning lever 36 F is depressed more steeply than any of the similar arrayed levers, like adjacent lever 36 E (FIG. 7 ), would be. A transient gap, 53 A, (FIG. 5) is created briefly by the projectile-driven downward rotation of rearward ganged support rod 38 (FIG. 5 ), which breaks the seating of dependent contact arm 46 A and lever detent 52 A (and of all other targets), thus permitting associated target 26 A to return to the erect mode. Similarly, as the rearward deflection of reset target 52 F is a transient one, since lacking any arrest effect by detent 52 F on arm 36 F, then that target concurrently returns to the erect mode, as shown in phantom. All six targets are now reset for another of shooting round.
With respect to the broken out perspective view of FIG. 7, the option of varying the resistance of a target, like 26 E, to projectile impact, will now be described. Helical spring 34 F provides an upright bias to target 26 E at its inner end, 351 , while the outer spring end, 35 O, is pinned to rotatable collar 41 . Collar 41 is locked upon shaft 28 via a set screw 41 S. By temporary release of set screw 41 S, and rotation of associated shaft of collar 41 , the biasing tension imposed upon target 26 E can be varied. Then, the set screw 41 S is tightened down to hold the new position for collar 41 . The purpose of this adjustment is to accommodate the variable projectile momentum of different bullets, from small caliber to higher powered rifles.
The reverse side, perspective view of FIG. 7 corresponds to the vertical sectional view of FIG. 5, and somewhat better depicts how each of deflected targets, 26 A/E, are arrested by the associated spanning lever means 36 A/E. This arrest mode exists until the target array reset sequence, just described above, is activated by firing upon adjacent reset target 26 F only. It is noteworthy that the force of the torsional bias provided by helical spring 40 F approximates the sum of forces provided by the bias of springs 40 A to 40 E.
The perspective view of the observe side of FIG. 8 is complemental of the display side (legs omitted), perspective view of FIG. 2 . Note that only targets 26 A and 26 D are deflected, and thus are held in the arrest position. The other three targets, 26 B, C, and E, are still upright as is, of course, reset target 26 F. At this juncture, if the shooter has expended all but one of his ammo clip of bullets, he can use his last shell to strike reset target 26 F, and thus to reset the entire target array. This is done either for starting his next clip of bullets or, as a courtesy, by resetting same for the next user of the target array. The entire target array, 26 A/F, will again display upright as in the schematic view of FIG. 1 .
In the reverse side of perspective view of FIG. 9, such corresponds to the sectional view of FIG. 1, and is the different configuration for the free end of lever 36 F, here being depicted in the stage of its maximum downward deflection by depending arm 26 F, which transient stage effects a gap (FIG. 5) between the depending arm and the detent-bearing lever, for each of targets 26 A/E. As noted, this transient gap permits each of the five targets to arcuately rotate to the vertical mode of FIG. 1, along with the reset target (R) itself. After reset, the several detents ( 52 ) mounted on spanning levers ( 36 ) are spaced apart from the lower ends of the depending target arms 46 . This target array deflection obtains until an induced deflection permits such a depending end arm ( 46 A) to pass over its associated offset detent, and then arrest the target in the position depicted in FIG. 5 .
In the broken out view of FIG. 10, the rod biasing assembly 40 A which regulates the rotatable action of spanning lever 36 A, via rearward elongate rod 38 is seen. As noted, lever 36 A, which extends transversely of elongate rods 28 and 38 , serves to cooperate with a depending lever arm 46 A (FIG. 5) and is pinned to rearward rod 38 , as are all other spanning levers, 36 A/F. Associated torsional spring 40 A provides the upward (clockwise) bias for lever 36 A, when the latter is freed to rotate arcuately. Erect post 41 A is mounted fixedly upon the 20 collar 36 T, which is pinned to elongate shaft 38 itself. Angle-shaped, linear detent component, 39 A, is aligned axially along rod 38 so as to provide an arrest element for the moving vertical post 41 A. As described in relation to correlated FIGS. 5 and 7, when lever 36 A rotates upwardly, post 41 A on collar 36 T makes contact with detent 39 A, which limits the arcuate rotation of free lever end 37 A to the arrest position depicted in FIG. 5 . This arrest feature obtains for each of levers 36 A/E. As to the target reset assembly 40 F of FIG. 6, such a detent component and associated post arrest device are unnecessary, for the reasons discussed previously. | A multiple target apparatus having an array of target plates arrayed linearly and pivotally on a first elongate shaft; a plurality of torsion providing components located on the first shaft are adapted to bias the targets in an upright mode; each target has a depending arm pinned to rotate upon the imposed deflection of a target by a speeding projectile to a latching position. Arrayed upon a spaced apart, second shaft are a like number of rigid levers spanning the lateral space between the first and second shafts. A detent on the one end of each of the depending arms is adapted to be contacted and arrested by the opposing lever until such are dislodged by a descrete target deflection and array reset, which are located at one end of the device, such that upon imposed rotation of the reset means, it also releases the latching position of the other targets. | 5 |