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CROSS-RELATED APPLICATIONS
The application is a divisional of and claims priority to application Ser. No. 09/935,735 filed Aug. 24, 2001 now U.S. Pat. 6,795,720.
BACKGROUND OF THE INVENTION
The present invention relates generally to a superconductive field coil winding in a synchronous rotating machine. More particularly, the present invention relates to a rotor core that supports a superconducting field winding assembly in a synchronous machine.
Synchronous electrical machines having rotor field coil windings include, but are not limited to, rotary generators, rotary motors, and linear motors. These machines generally comprise a stator and rotor that are electromagnetically coupled. The rotor may include a multi-pole rotor core and one or more field coil windings mounted on the rotor core. The rotor cores may include a magnetically-permeable solid material, such as an iron-core rotor.
Conventional copper windings are commonly used in the rotors of synchronous electrical machines. However, the electrical resistance of copper windings (although low by conventional measures) is sufficient to contribute to substantial heating of the rotor and to diminish the power efficiency of the machine. Recently, superconducting (SC) field coil windings have been developed for rotors. SC windings have effectively no resistance and are highly advantageous rotor coil windings.
Iron-core rotors saturate at an air-gap magnetic field strength of about 2 Tesla. Known superconductive rotors employ air-core designs, with no iron in the rotor, to achieve air-gap magnetic fields of 3 Tesla or higher. These high air-gap magnetic fields yield increased power densities of the electrical machine, and result in significant reduction in weight and size of the machine. Air-core superconductive rotors require large amounts of superconducting wire. The large amounts of SC wire add to the number of coils required, the complexity of the coil supports, and the cost of the SC coil windings and rotor.
High temperature SC rotor coil field windings are formed of superconducting materials that are brittle, and must be cooled to a temperature at or below a critical temperature, e.g., 27° K, to achieve and maintain superconductivity. The SC windings may be formed of a high temperature superconducting material, such as a BSCCO (Bi x Sr x Ca x Cu x O x ) based conductor.
High temperature superconducting (HTS) coil windings are sensitive to degradation from high bending and tensile strains. These coils must undergo substantial centrifugal forces that stress and strain the coil windings. Normal operation of electrical machines involves thousands of start up and shut down cycles over the course of several years that result in low cycle fatigue loading of the rotor. Furthermore, the HTS rotor coil windings should be capable of withstanding 25% over-speed operation during rotor balancing procedures at ambient temperature, and at occasional over-speed conditions at cryogenic temperatures during power generation operation. These over-speed conditions substantially increase the centrifugal force loading on the rotor coil windings over normal operating conditions.
SC coils used as the HTS rotor field winding of an electrical machine are subjected to stresses and strains during cool-down and normal operation. These coils are subjected to centrifugal loading, torque transmission, and transient fault conditions. To withstand the forces, stresses, strains and cyclical loading, the SC coils should be properly supported in the rotor by a coil support system. These coil support systems hold the SC coil(s) in the HTS rotor and secure the coils against the tremendous centrifugal forces due to the rotation of the rotor. Moreover, the coil support system protects the SC coils, and ensures that the coils do not prematurely crack, fatigue or otherwise break.
Developing coil support systems for HTS coil has been a difficult challenge in adapting SC coil windings to HTS rotors. Examples of coil support systems for HTS rotors that have previously been proposed are disclosed in U.S. Pat. Nos. 5,548,168; 5,532,663; 5,672,921; 5,777,420; 6,169,353, and 6,066,906. However, these coil support systems suffer various problems, such as being expensive, complex and requiring an excessive number of components. There is a long-felt need for a HTS rotor having a coil support system for a SC coil. The need also exists for a coil support system made with low cost and easy to fabricate components.
BRIEF SUMMARY OF THE INVENTION
A multi-piece rotor core for a superconducting synchronous machine has been developed. The rotor core includes passages transverse to the rotor axis. Through these passages extend coil support bars that are coupled to a superconducting coil winding. The coil winding extends around the rotor core, and is generally in a plane that includes the rotor axis. The rotor core has flat sides that are adjacent the long sides of the coil winding.
The rotor core is assembled from several rotor core sections. These sections are generally disk shaped and have a T-shaped cross-section. The rotor core sections have connection bosses to engage slots in adjacent rotor core sections. The core sections are assembled around a pre-formed superconducting winding and coil support. The assembly of rotor core sections form a solid core, except for the support bar passages that extend through the core axis. The core sections are held together by tie rods that extend through the assembly of sections. The rods are parallel to the rotor core axis and extend the length of the core.
Tension bars that extend between the sides of the rotor coil can provide support so that the coil will withstand the centrifugal forces of the rotor. To support opposite sides of the coil, the tension bars extend through rotor core. There is a desire to assembly the tension bar and coil winding before both are mounted on a rotor core. However, a solid rotor core will not allow for pre-assembly of the coil and tension members. Thus, there is a need for a rotor core and assembly technique that will allow an assembled coil and tension member to be mounted on a solid rotor core.
An assembly of rotor core sections permits the rotor core to be assembled around a coil winding assembly. The coil winding assembly may be assembled with the winding support to form a pre-formed coil winding assembly prior to the rotor core assembly. Pre-assembly of the field coil and winding support should reduce the rotor-coil production cycle, improve coil support quality, and reduce coil assembly variations.
The HTS rotor may be for a synchronous machine originally designed to include SC coils. Alternatively, the HTS rotor may replace a copper coil rotor in an existing electrical machine, such as in a conventional generator. The rotor and its SC coils are described here in the context of a generator, but the HTS coil rotor is also suitable for use in other synchronous machines.
In a first embodiment, the invention is a rotor in a synchronous machine, comprising: a superconducting field winding assembly having a coil winding and at least one winding support extending between opposite sides of the winding, and a rotor core formed of a plurality of rotor core sections, each of said core sections having a slot to receive said winding support.
In another embodiment, the invention is a rotor core and winding assembly comprising: separable rotor core sections assembled around the winding assembly to form said rotor core, where said core sections are axially aligned with said rotor core, and said winding assembly includes a pre-assembled a superconducting field winding and a center winding support.
Another embodiment of the invention is a method for assembling a rotor core around a superconducting field coil winding assembly comprising the steps of: fabricating said field coil winding assembly by assembling a field coil winding and a coil support prior to assembly of the rotor core, inserting a portion of each of a plurality of rotor core sections partially through said coil winding assembly, assembling the plurality of rotor core sections around said coil support, and securing the assembly of rotor core sections.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings in conjunction with the text of this specification describe an embodiment of the invention.
FIG. 1 is a schematic side elevational view of a synchronous electrical machine having a superconductive rotor and a stator.
FIG. 2 is a perspective view of an exemplary racetrack superconducting coil winding.
FIG. 3 is a cross-sectional view of an assembled rotor core with a coil winding.
FIG. 4 is a cross-sectional diagram of the assembled rotor core taken along line 4 — 4 in FIG. 3 .
FIG. 5 is a perspective diagram of a rotor core end section.
FIG. 6 is a cross-sectional diagram of a rotor core section.
FIG. 7 is a cross section of the rotor core taken along line 7 – 7 of FIG. 3 .
FIG. 8 is a cross-section of a coil winding, section of a tension bar and coil housing.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an exemplary synchronous generator machine 10 having a stator 12 and a rotor 14 . The rotor includes field winding coils that fit inside the cylindrical rotor cavity 16 of the stator. The rotor fits inside the rotor cavity of the stator. As the rotor turns within the stator, a magnetic field 18 (illustrated by dotted lines) generated by the rotor and rotor coils moves/rotates through the stator and creates an electrical current in the windings of the stator coils 19 . This current is output by the generator as electrical power.
The rotor 14 has a generally longitudinally-extending axis 20 and a generally solid, multi-piece rotor core 22 . The rotor core is an assembly of axially-aligned end core sections 44 and middle core sections 46 . The core 22 has high magnetic permeability, and is usually made of a ferromagnetic material, such as iron. In a low power density superconducting machine, the iron core of the rotor is used to reduce the magnetomotive force (MMF), and, thus, minimize the amount of superconducting (SC) coil wire needed for the coil winding.
The rotor 14 supports at least one longitudinally-extending, racetrack-shaped, high-temperature superconducting (HTS) field winding assembly 33 having an HTS winding (See FIG. 2 ). The HTS field coil winding may be alternatively a saddle-shape or have some other shape that is suitable for a particular HTS rotor design. A rotor field assembly and coil support is disclosed here for a racetrack SC field winding. The rotor core assembly and coil support may be adapted for winding configurations other than a racetrack field winding mounted on a solid rotor core.
The rotor includes a pair of end shafts 24 , 30 that are supported by bearings 25 . The end shafts may be coupled to external devices. For example, one of the end shafts 24 has a cryogen transfer coupling 26 to a source of cryogenic cooling fluid used to cool the SC field windings in the rotor. The cryogen transfer coupling 26 includes a stationary segment coupled to a source of cryogen cooling fluid and a rotating segment which provides cooling fluid to the HTS winding. This end 24 of the rotor may also include a collector 31 for electrically connecting to the rotating SC field winding. The opposite end shaft 30 of the rotor may be driven by a power turbine coupling 32 .
FIG. 2 shows an exemplary HTS racetrack field winding assembly 33 comprising a field coil winding 34 and a series of tension bars 35 (the coil support) extending between opposite sides of the winding. The winding assembly 33 is fabricated with the field winding 34 and tension bars 35 before the assembly 33 is inserted into the rotor core. The tension bars support the field coil windings with respect to the centrifugal forces that act on the windings as the rotor spins during operation. Accordingly, the tension bars are attached to the windings by a winding housing 36 (as shown in FIG. 8 ). The housing and tension bars restrain the expansion of the field coil winding 34 that would otherwise occur with the tension bars 35 .
The SC field windings 34 of the rotor includes a high temperature superconducting (SC) winding 34 . Each SC winding includes a high temperature superconducting conductor, such as a BSCCO (Bi x Sr x Ca x Cu x O x ) conductor wires laminated in a solid epoxy impregnated winding composite. For example, a series of BSCCO 2223 wires may be laminated, bonded together and wound into a solid epoxy impregnated winding.
SC wire is brittle and easy to be damaged. The SC winding is typically layer wound SC tape that is epoxy impregnated. The SC tape is wrapped in a precision winding form to attain close dimensional tolerances. The tape is wound around in a helix to form the racetrack SC winding 34 .
The dimensions of the racetrack winding are dependent on the dimensions of the rotor core. Generally, each racetrack SC winding encircles the magnetic poles of the rotor core, and is parallel to the rotor axis. The field windings are continuous around the racetrack. The SC windings form a resistance free electrical current path around the rotor core and between the magnetic poles of the core. The winding has electrical contacts 41 that electrically connect the winding to the collector 31 .
Fluid passages 38 for cryogenic cooling fluid are included in the field winding 34 . These passages may extend around an outside edge of the SC winding 34 . The passageways provide cryogenic cooling fluid to the porous winding and remove heat from the winding. The cooling fluid maintains the low temperatures, e.g., 27° K., in the SC field winding needed to promote superconducting conditions, including the absence of electrical resistance in the winding. The cooling passages have an input and output fluid ports 39 at one end of the rotor core. These fluid (gas) ports 39 connect the cooling passages 38 on the SC winding to the cryogen transfer coupling 26 .
Each HTS racetrack field winding 34 has a pair of generally straight side portions 40 parallel to a rotor axis 20 , and a pair of end portions 42 that are perpendicular to the rotor axis. The side portions of the field coil winding are subjected to the greatest centrifugal stresses. Accordingly, the side portions are supported by the tension bars and housing. These bars and housing form a winding support system that counteract the centrifugal forces that act on the winding.
FIG. 3 is a schematic diagram of a multi-piece rotor core 22 with the winding assembly 33 , including the racetrack superconducting coil field winding 34 and tension bars 35 . The iron core is made of multiple core sections, which are generally several middle sections 44 and a pair of end sections 46 . Each of the core sections have a semi-rectangular shape (see FIG. 7 ) with a pair of opposite flat sides 50 and a pair of opposite arc-shaped sides 52 .
When assembled, the flat sides 50 of the core sections are in alignment with each other, and similarly the arc-shaped sides are also in alignment. The middle core sections 44 have a generally “T” shape in cross sections, except for the two end sections (compare FIGS. 5 and 6 ). The end sections 46 have a generally L-shaped cross section.
The sections of the rotor core are assembled around the winding assembly 33 . During assembly of the core, the narrow head 45 of each middle section slides between adjacent support bars 35 in the winding assembly. The narrow head of the end rotor core sections 46 slide between a tension bar 35 and an end 42 of the coil winding 34 . Each of the core sections has at least one tension rod slot 53 (middle sections 44 have a pair of opposite slots) which when mated with the slot in an opposite core forms an aperture 55 for a tension bar 35 . The assembly of rotor core sections permits integrating a fully assembled winding assembly 33 (which includes, for example, field winding 34 and tension bars 35 ) into the rotor core.
The core sections 44 , 46 may be iron core forgings. The rotor core sections are assembled through rabbet joint fits for concentricity and alignment. Each core section has at least one boss 54 (middle sections have a pair of opposing bosses) that fit into a slot 56 on an adjacent core section. The boss-slot connection between the core sections aligns the core sections in the rotor core. Several tie-rods 58 extend laterally through rod holes 60 along the length of the rotor core. The tie rods have a nut or other faster at each end and hold the core sections together in compression.
A vacuum housing 64 may be formed over the field winding 34 , once the rotor core sections have been assembled around the winding assembly. A vacuum around the winding facilitates the superconducting characteristics of the winding. The vacuum housing provides a vacuum over the entire race-track shape of the coil winding.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover all embodiments within the spirit of the appended claims. | A rotor core and winding assembly including: separable rotor core sections assembled to form the rotor core, where the core sections each have a substantially circular perimeter and are axially aligned when assembled as the core, and the winding assembly includes a pre-assembled superconducting field winding and a winding support, wherein the winding support extends between adjacent core sections in the assembled rotor core. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention.
The invention relates, in general, to the drilling of wells. More specifically, the invention relates to the spinning together and apart segments of drill pipe such as are used in the drilling of oil and water wells.
2. Related Art.
The drilling of deep holes requires the attachment of many segments of pipe in series. These connections may conventionally be made by threading the male end at the bottom of one pipe into the female end of another. These holes are lengthened as additional pipe lengths are successively added to the drill string in this manner. To remove the drill string, this process is reversed. The present invention offers a device that makes the formation and removal of such strings easier, safer, and quicker.
A number of inventions have attended to the desire for a simple and useful machine for spinning drill pipe. These devices employ a number of different mechanisms for retaining and spinning lengths of pipe.
Rauch, U.S. Pat. No. 6,065,372, offers a power wrench for spinning drill pipe in which the subject pipe length is pressed firmly against two serrated rollers by an idler roller that is actuated by an air ram. The serrated rollers, driven by means of drive chains and a single hydraulic motor, impart spin to the pipe.
Rae, U.S. Pat. No. 5,660,087, discloses a pipe spinner in which a multiplicity of symmetrically located rollers engage and rotate drill pipe sections which are held in place under the force of a piston rod that extends via a bell crank to clamp the pipe.
Brooks, U.S. Pat. No. 4,381,685, provides a power wrench in which a single motor drives a single serrated drum designed to engage and spin the subject pipe segment. The pipe is pressed into firm contact with the serrated surface of the drum using a C-shaped clamp.
Hudson, U.S. Pat. No. 4,221,269, describes a power wrench in which a drill pipe length is received between three urethane-coated rollers that are driven by three rotary hydraulic motors to spin the pipe.
Bartos, U.S. Pat. No. 3,392,609, presents a drill pipe spinning apparatus in which a drill pipe is engaged and rotated by two sets of rollers situated one above the other. Other power wrenches for drill pipe are presented in other patents. However, none of these employ the specific configuration or realize the intrinsic advantages of the present invention.
SUMMARY OF THE INVENTION
The present invention is a device for spinning together and breaking apart the joints of drill strings used in well construction. The invention makes these processes safer, quicker, and more convenient for well drillers.
The invention comprises a wrench system that meets requirements for handling operations involving larger drilling pipes or rods, including casings, preferably 6 to 16 inches in diameter. The preferred components of the wrench include: two (2) pairs of serrated power rollers for gripping the pipe, two (2) hydraulic motors used in conjunction with two (2) pairs of drive chains and double sprockets for spinning the serrated rollers, an adjustment mechanism for the wrench to fit various size pipes, and an attachment means for moveably securing the apparatus to a drill rig. The preferred embodiment also includes a system for minimizing the operational risks associated with using the tool.
The apparatus is designed to hang, by wire cable or other suitable means, from the mast of any established drill rig and is easily positioned manually by the operator. The preferred supporting elements, which are typically available on drill rigs, include hydraulic power to run the motors and compressed air to drive the air rams. The invention preferably includes a safety feature comprising a simple switch or other suitable control means. When in the “off” position, the switch prevents the moving parts from engaging, thereby minimizing the risk of injury to machine operators.
Operation of the wrench requires first manually positioning the device's pair of arms about the subject pipe segment and securing the segment between the pairs of serrated rollers. The arms are first manually adjusted to accommodate the approximate outer diameter of the subject pipe length, and secondly the actuation of two air rams closes the arms tightly upon the pipe segment. With the pipe length gripped tightly, the two hydraulic motors spin the rollers to impart spin to the pipe. The motors continue to drive the rollers until the threaded male end of one pipe is securely seated within, or removed from, the female end of another.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of the invented power wrench with the chain guard removed for clarity.
FIG. 2 is a top view of the power wrench depicted in FIG. 1 , but with the chain guards installed, and with a large pipe engaged for spinning.
FIG. 3 is a top view of the power wrench depicted in FIG. 2 , but with a smaller pipe engaged.
FIG. 4 is a partial, side crossectional view along lines 4 — 4 of FIG. 1 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the figures, several views of the invented power wrench 10 are presented. The majority of the preferred components are shown and numbered in all figures and, for illustrative purposes, a pipe length in position for spinning is included in FIGS. 2 and 3 . To simplify the description, the components will be separated into two functional systems: the drive assembly and the engagement assembly.
The structural base for both systems is comprised of a T-shaped frame 12 and two engaging arms 14 and 14 ′. The frame 12 and engaging arms are shown in top view in FIGS. 1-3 . The engaging arms 14 and 14 ′ are constructed of a top and bottom cheek plate, 16 and 16 ′, respectively with attendant bolts and spacers as shown in FIG. 4 . The cheek plates 16 and 16 ′ are moveably mounted to the frame 12 such that the wings 18 of the frame are positioned between the top and bottom cheek plate, as shown in FIG. 4 . These components are preferably constructed of ⅜″ T-1 steel plate, although those skilled in the art may substitute possible alternatives. The configuration of the arms and frame, such as the placement of axle holes and spacers, may vary to the extent that adjustment of the performance of the essential functions of each is still possible.
The drive assembly preferably includes two hydraulic motors 20 and 20 ′, one on each engaging arm. The motors are situated beneath the operating parts and are protected by motor guards 22 and 22 ′, respectively, as shown in FIGS. 2 and 3 . Each motor will drive a pair of drive chains 24 connected to a double sprocket assembly 25 . The double sprocket assembly 25 preferably comprises an upper and lower toothed sprocket portion arranged co-axially on the motor-driven axle. The double sprocket drives two endless chain drives. At the end of each drive chain, opposite the double sprocket, are upper and lower roller sprockets 26 and 26 ′, respectively. These roller sprockets are preferably situated at or near the top of the upper and lower roller axles such that the upper roller sprocket lies in the same plane as the upper double sprocket and the lower roller sprocket lies in the same plane as the lower double sprocket. The upper and lower roller double sprockets rotate the upper and lower drive chains, respectively. Other arrangements are possible where the desired interaction between the roller sprockets and the double sprocket is accomplished. The preferred configuration incorporates 14 toothed sprockets with taper lock and number 50 chain drives with ⅝″ pitch. The roller axles extend through the top and bottom cheek plates and the ends are secured to the appropriate plate by means of a sealed ball bearing or other suitable connection. Rotation of the roller sprockets drives the distal and proximal rollers, 28 and 28 ′, respectively, which engage and spin the subject pipe length.
The serrated distal and proximal rollers are configured co-axially with the upper and lower roller sprockets. When engaged, the serrated surface grips the outer surface of the received pipe length to impart spin to the pipe. The toothed surface significantly enhances the frictional contact between the rollers and the drill pipe. The rollers in the preferred embodiment are approximately 5″ in diameter and 3″ wide. To initiate spinning, the hydraulic motors are started slowly once the subject pipe length is clamped tightly between the two pairs of serrated rollers situated at the forward end of the engaging arms and surrounding the pipe-receiving space, as shown in FIGS. 2 and 3 .
Sufficient engagement of the drill pipe to the power rollers is accomplished by closing the engaging arms 14 and 14 ′ tightly upon the pipe segment. The engaging arms of the preferred embodiment may be adjusted in two ways. Adjustment of the swivel pins 30 and 30 ′ permits abduction and adduction of the engaging arms along the frame to make large adjustments. The swivel pins 30 and 30 ′ may be secured in various positions along the wings of the frame to increase or decrease the pipe-receiving space as desired. Small adjustments, such as those required to fully clamp the pipe within the pairs of rollers, are accomplished via two compressed air rams 32 and 32 ′ that can be driven in or out. As shown in FIGS. 1-3 , the air rams 32 and 32 ′ are attached at their distal ends to the back end of the engaging arms, opposite the rollers, and one attached at their proximal ends to frame 12 . This way, upon actuation, the air ram 32 and 32 ′ generate a pivoting motion about the swivel pins. Extension of the air rams tightens the arms upon the pipe, and retraction of the rams releases the drill pipe segment. The engaging arms 14 and 14 ′ are driven uniformly by the air rams to ensure that the drill rod segment contacts both sets of rollers equally and aligns with the center of the receiving space.
The invented system allows the drill pipe segment to be clamped between the engaging arms in firm contact with the serrated rollers. The pipe length may then be spun into, or out of, proper engagement with another pipe length to install or remove long drill strings. The mechanisms involved with engagement and driving of the invented power wrench are both simple and reliable.
For use, the power wrench is typically suspended by a wire cable, or other suitable connection, from a point at or near the top of a drill rig mast. In one embodiment, a cable 34 is connected to the two eyelets 36 and 36 ′ on the power wrench at a height appropriate for manual operation of the tool. The eyelets 36 ans 36 ′ are positioned such that the cable 34 connected from one eyelet to the other intersects the center of gravity of the wrench. With the tool connected, secured, and suspended from the cable in this manner, the machine operator may easily grasp the balanced wrench by a pair of handles and position it near the subject drill pipe or move it to an out of the way place.
The wrench requires the use of a bracing mechanism when operational to counteract the reactionary spinning forces imparted to the device by the drill string. A stop bar (not shown) is employed to brace the power wrench against an available, stable structure such as a mast post. The wrench must be started slowly to allow the stop bar to position itself securely against the mast or other structure.
To initiate operation of the tool, the safety mechanism must first be inactivated. This mechanism prevents unintentional activation of the machine due to accidental contact with the control levers. The safety comprises a means of locking the compressed air control lever in an inactivated state that prohibits movement of the lever without first intentionally releasing the lever. When locked in place, the safety prohibits the arms from engaging. This allows operators and laborers to work safely around the device with minimal risk of accidental injury. When the mechanism is released the arms are free to close upon the subject drill rod. The safety is positioned so that it is easily within the reach of the operator.
To engage, the operator moves the wrench such that the arms surround, and possibly contact, the subject drill rod and the air rams are then actuated to clamp the rod firmly between the pairs of rollers. With the arms engaged, the rollers are turned by the hydraulic motors until the spinning procedure is satisfactorily completed, i.e., until the male end of one rod is tightly seated within, or removed from, the female end of another.
Although this invention has been described above with reference to particular means, materials and embodiments, it is to be understood that the invention is not limited to these disclosed particulars, but extends instead to all equivalents within the scope of the above description, included drawings and the following claims. | An adjustable power wrench is provided for spinning together, and apart, sections of pipe used in long drill strings such as are typically seen in water well and oil drilling. The wrench is preferably designed for use with large diameter drill pipes or rods, including casings. Two sturdy engaging arms, each containing a pair of serrated power rollers driven by a hydraulic motor, are manually positioned about the subject pipe length. The arms are closed about the pipe by two air rams, one for each engaging arm, to engage the serrated rollers and impart spin to the pipe. The apparatus is preferably supported by wire cable in a balanced fashion from the mast of an available drill rig. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS:
This application is a §371 National Phase of PCT/EP2009/065728, filed 24 Nov. 2009, which claims priority from European Application 08169901.9, filed 25 Nov. 2008.
FIELD OF THE INVENTION
The present invention refers to 3-aza-bicyclo[3.2.1]octane derivatives of general formula (I) useful in the treatment of infectious diseases and particularly pathologies caused by microbial pathogens expressing aspartyl-protease activity. Specifically, the invention refers to compounds of general formula (I), and their metabolites, as Candida albicans SAP2 inhibitors for treating fungus infections, as HIV protease inhibitors for treating HIV infections, or as plasmepsines or histo-aspartyl protease (HAP) inhibitors for treating malaria.
STATE OF THE ART
Aspartyl proteases are widely distributed in many organisms and tissues with different physiological and functional properties, and contain two aspartyl residues at the active site, one protonated and the other not, which work together as general acid-base catalysis. A water molecule bound between the two aspartate residues is believed to be the nucleophile for the amide bond hydrolysis, and it is activated by the deprotonated catalytic aspartic acid residue. To catalyse peptide hydrolysis, the two aspartic residues must be close enough in the tertiary structure of the molecule. Most of the aspartic proteases belong to the pepsin family, including digestive enzyme such as pepsin and chimotrypsin, as well as lysosomal cathepsins D and processing enzymes such as renin and certain fungal proteases (the Candida albicans SAPs, penicillopepsin etc). A second family comprises viral proteases such as the HIV, also called retropepsin. The active site of aspartic proteases does not in general contain groups that are sufficiently nucleophilic to be chemically modified by a selective irreversible inhibitor. Thus, most of the aspartic protease inhibitors developed to date binds to their target enzyme through non covalent interactions. These compounds are therefore reversible inhibitors and an effective inhibition results when the enzyme shows higher affinity for the inhibitor than for its natural substrate (Tacconelli, E. et al. Curr. Med. Chem. 2004, 4, 49).
It has been proposed that stable structures which resemble the transition state of an enzyme-catalysed reaction should bind the enzyme more tightly than the substrate. As a consequence, an approach that has been very successful for the design of efficient aspartyl protease inhibitors is based on the incorporation of a transition state isostere into a peptidomimetic structure.
Candida albicans is an opportunistic fungal pathogen that causes severe systemic infections especially in immunodeficient individuals. Although a certain number of antifungal agents are available, the need for new drugs against C. albicans is escalating due to both the widespread occurrence of mucosal and systemic infections caused by Candida , and the development of resistance against available drugs (Shao, P.-L. et al. Int. J. Antimicrob. Agents 2007, 30, 487). In fact, despite drug availability, Candida albicans ranks as a highly incident cause of morbility, cost of hospitalization and mortality (Pfaller M A & D: J: Diekema. Epidemiology of invasive Candidiasis: a persistent public health Problem. Clin.Microbiol.Rev. 2007; 20:133-163). Although the ability to cause disease is likely a complex process involving multiple interactions between Candida and the host, Secreted Aspartyl Proteases (SAPs) activity appears to be a major virulence factor and therefore offers a potential target for drug intervention in infections. The Candida strains express at least nine distinct genes (SAP1-9) during the course of the same disease but to different stages of infection, indicating that the different SAPs have different functions (Schaller, M. et al. J. Invest. Dermatol. 2000, 114, 712); particularly, among them SAP2 is one of the most expressed enzymes implicated in host persistent colonization and invasion.
Other strong evidence of the need of inhibitors of aspartyl protease activity are due to the following aspects:
Immunodeficient patients suffering of infections caused by Candida albicans can develop systemic candidiasis and also resistance to common therapeutics. HIV and HTVL viruses rely upon their aspartyl proteases for viral maturation. Plasmodium falciparum uses plasmepsines I and II for processing hemoglobin.
Recently, the inhibitory activity of HIV protease inhibitors (HIV-PI) against pathogenic microorganisms in which aspartyl proteases play a key role has been demonstrated (Tacconelli et al., Curr. Med. Chem., 2004, 4, 49). Particularly, HIV-PI show micromolar activity towards aspartyl proteases of both Candida albicans (Cassone et al., J. Infect. Dis., 1999, 180, 448), and malaria plasmepsines II and IV (Andrews et al., Antimicrob. Agents Chemother. 2006, 639). Such results are in agreement with the flexibility of these molecules and some structural analogy between aspartyl proteases of HIV-1 and SAP2 of Candida albicans.
Thus, new compounds having inhibitory activity towards aspartyl proteases can act as Candida albicans SAP2 inhibitors for treating fungus infections, as HIV protease inhibitors for treating HIV infections, as plasmepsines or histo-aspartyl protease (HAP) inhibitors for treating malaria.
wherein:
R1 is chosen in the group consisting of H, benzyl, p-methoxybenzyl, benzhydryl; preferably benzyl;
R2 is a chosen in the group consisting of H, alkyl, aryl, alkylaryl; preferably H, benzyl, methyl, isobutyl.
R3 and R4 are independently chosen in the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, alkylaryl, aryl, hydroxyalkyl, alkoxyalkyl, alkoxycarbonyl, —CH(α-amino acid side chain)CH2OH; preferably H, hydroxyethyl, propargyl, —CH(Leu side chain)CH2OH;
R3 and R4 together with the nitrogen atom they are bonded to can form a cycle, eventually substituted; preferably piperidine, 4-hydroxyethyl-piperazine, 4-carboethoxy-piperazine, morpholine; including all the possible combinations of stereoisomers;
are known.
Their preparation has been reported in J. Org. Chem. 1999, 64, 7347 ; J. Org. Chem. 2002, 67, 7483 ; Bioorg. Med. Chem. 2001, 9, 1625 ; Eur. J. Org. Chem. 2002, 873 ; J. Org. Chem. 2002, 67, 7483 ; C. R. Chimie 2003, 631 ; J. Comb. Chem. 2007, 9, 454.
Their use in pharmaceutical compositions for the treatment of pathologies related to deficit of neurotrofines activity has been described in WO2004/000324.
Thus, aim of the present invention is to furnish alternative compounds for the preparation of medicaments for the treatment of pathologies related to aspartyl protease activity, and specifically of SAP2, and more specifically for the treatment of pharmaco-resistant systemic infections of Candida albicans in immunodepressed patients.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 —Vaginal infection with C. albicans SA40 in rats intravaginally treated with APG12 after challenge (1, 24, 48 hrs)
FIG. 2 —Vaginal infection with C. albicans AIDS 68 in rats intravaginally treated with APG12 after challenge (1, 24, 48 hrs)
DETAILED DESCRIPTION OF THE INVENTION
The present invention refers to compounds of formula (I)
wherein:
R1 is a —CH(R)COR5; R is a α-amino acid side chain, preferably said α-amino acid is chosen among the group consisting of Gly, Leu, Val, Ile, Ala, Phe, Phg, Nle, Nva; R2 is H, alkyl, aryl, alkylaryl, preferably H, benzyl, methyl, isobutyl; R3 and R4 are independently chosen in the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, alkylaryl, aryl, hydroxyalkyl, alkoxyalkyl, alkoxycarbonyl, —CH(α-amino acid side chain)CH2OH; preferably H, hydroxyethyl, propargyl, —CH(Leu side chain)CH2OH; R3 and R4 together with the nitrogen atom they are bonded to can form a 5 to 8 membered cycle, eventually substituted; preferably piperidine, 4-hydroxyethyl-piperazine, 4-carboethoxy-piperazine, 4-benzyl-piperazine, 4-phenethyl-piperazine, morpholine; R5 is chosen in the group consisting of —Oalkyl, —Oaryl, —NHalkyl, NHaryl, amino acid, peptide; preferably —OCH3, NHCH2CH(OH)CH2CONHBu;
including all the possible combinations of stereoisomers.
Surprisingly, it has been discovered that compounds of formula (I)
wherein:
R1 is chosen in the group consisting of benzyl, phenyl, —CH(R)COR5; preferably benzyl, —CH(R)COR5; R is a α-amino acid side chain; preferably said α-amino acid is chosen among the group consisting of Gly, Leu, Val, Ile, Ala, Phe, Phg, Nle, Nva; R2 is H, alkyl, aryl, alkylaryl, preferably H, benzyl, methyl, isobutyl; R3 and R4 are independently chosen in the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, alkylaryl, aryl, hydroxyalkyl, alkoxyalkyl, alkoxycarbonyl, —CH(α-amino acid side chain)CH2OH; preferably H, hydroxyethyl, propargyl, —CH(Leu side chain)CH2OH; R3 and R4 together with the nitrogen atom they are bonded to can form a 5 to 8 membered cycle, eventually substituted; preferably piperidine, 4-hydroxyethyl-piperazine, 4-carboethoxy-piperazine; R5 is chosen in the group consisting of —Oalkyl, —Oaryl, —NHalkyl, NHaryl, α-amino acid, peptide; preferably —OCH3, NHCH2CH(OH)CH2CONHBu;
including all the possible combinations of stereoisomers;
are potent inhibitors both in vitro and in vivo of SAP2, thus they can be used for the preparation of medicaments for treating infectious diseases, preferably related to Candida albicans , HIV, HTVL, Plasodium falciparum.
An aspect of the present invention relates to pharmaceutical compositions containing at least a compound of formula (I), wherein R1 is —CH(α-amino acid side chain)COR5; preferably such α-amino acid is chosen in the group consisting of Gly, Leu, Val, Ile, Ala, Phe, Phg, Nle, Nva; and at least another pharmaceutically acceptable ingredient, excipient, carrier or diluent.
According to the invention:
Alkyl means linear or branched radical chain, such as: methyl, ethyl, propyl, isopropyl, butyl, pentyl, hesyl, heptyl, octyl, ethenyl, propenyl, butenyl, isobutenyl, acetylenyl, propynyl, butynyl, etc. . . . ;
Aryl means aromatic or heteroaromatic ring containing heteroatoms like N, O, S. Amino acid side chain means diverse substitution as a side chain bound to an “amino acid”. The term “amino acid” includes every natural α-amino acids of the L or D series having as “side chain”: —H for glycine; —CH3 for alanine; —CH(CH3)2 for valine; —CH2CH(CH3)2 for leucine; —CH(CH3)CH2CH3 for isoleucine; —CH2OH for serine; —CH(OH)CH3 for threonine; —CH2SH for cysteine; —CH2CH2SCH3 for methionine; —CH2-(fenil) for phenylalanine; —CH2-(fenil)-OH for tyrosine; —CH2-(indole) for tryptophan; —CH2COOH for aspartic acid; —CH2C(O)(NH2) for asparagine; —CH2CH2COOH for glutamic acid; —CH2CH2C(O)NH2 for glutamine; —CH2CH2CH2-N(H)C(NH2)NH for arginine; —CH2-(imidazole) for hystidine; —CH2(CH2)3NH2 for lysine, comprising the same side chains of amino acids bearing suitable protecting groups. Moreover, the term “amino acid” includes non natural amino acids, such as ornitine (Orn), norleucine (Nle), norvaline (NVa), β-alanine, L or D α-phenylglycine (Phg), diaminopropionic acid, diaminobutyric acid, aminohydroxybutyric acid, and other well known in the state of the art of peptide chemistry.
Scheme 1 summarizes the synthetic preparation of compounds of formula (I) as described above, wherein R1 is —CH(R)COR5, R is a α-amino acid side chain, from commercially available or easily synthesizable α-amino-acid derivatives (II).
Reductive alkylation of the amino acid derivative (II) with a commercially available or easily synthesisable dicarbonyl derivative, for example dimethoxy-acetaldehyde, in a protic solvent, preferably methanol, using a reducing agent, preferably H2 and a catalyst, preferably Pd/C, affords the secondary amine (III) after stirring at ambient temperature, preferably 16 h at 25° C. Alternatively, compound (II) is heated with a commercially available or easily synthesisable acetal derivative containing a good leaving group (X in Scheme 1), for example bromoacetaldehyde dimethylacetal, preferably at 120° C., in a polar solvent, preferably DMF, in the presence of a base, preferably NEt3, and in the presence of a catalyst, preferably KI. Amine (III) is successively converted into the amide (IV) through a coupling reaction with di-O-acetyl-tartaric anhydride. Treatment of crude (IV) with an acid in a polar solvent, preferably thionyl chloride in MeOH affords cyclic acetal (V) which is further heated in a non-polar solvent, preferably in refluxing toluene for 30 min, in the presence of an acid catalyst, preferably H2SO4 over silica gel, to yield (VI).
The synthesis of amides (I) is accomplished without using activating agents, by heating the methyl ester (VI) in the presence of the neat amine, preferably at 60° C. for 18 h.
The following examples are reported to give a non-limiting illustration of the present invention.
EXPERIMENTAL DETAILS
Example 1
(2S)-4-Methyl-2-[(1R,5S,7S)-2-oxo-7-(piperidine-1-carbonyl)-6,8-dioxa-3-aza-bicyclo[3.2.1]oct-3-yl]-pentanoic acid methyl ester [compound formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2(CH2)3CH2-]
A solution containing L-leucine methyl ester hydrochloride (2.9 g, 16 mmol), 2-bromo-1,1-dimethoxy ethane (1.9 ml, 2.7 g, 16 mmol), NEt3 (6.7 ml, 48 mmol) and a catalytic amount of KI in DMF (190 ml) was stirred at 120° C. for 3 days. The reaction mixture was concentrated under reduced pressure, diluted with water and extracted with DCM. The organic layer was then washed with brine, dried over Na2SO4 and evaporated. The crude product was purified by column chromatography (silica gel, EtOAc/P.E. 1:1) to afford compound of formula (III), where R=Leu side chain, as a yellow oil (1.2 g, 32% yield).
[α] D 24 −3.32 (c 1.0, CHCl 3 ); 1 H-NMR (CDCl3, 200 MHz): δ 4.38 (t, J=6 Hz, 1H), 3.65 (s, 3H), 3.30 (s, 3H), 3.29 (s, 3H), 3.24 (t, J=6 Hz, 1H), 2.68 (dd, J 1 =J 2 =6 Hz, 1H), 2.52 (dd, J 1 =J 2 =6 Hz, 1H), 1.71-1.55 (m, 2H), 1.44-1.37 (m, 2H), 0.86 (d, J=4 Hz, 3H), 0.83 (d, J=4 Hz, 3H); 13 C-NMR (CDCl3, 200 MHz): δ 175.9 (s), 103.6 (d), 59.9 (d), 54.0 (q), 53.1 (q), 51.7 (q), 49.3 (t), 42.8 (t), 25.0 (d), 22.8 (q), 22.5 (q); MS m/z 233 (0.5), 202 (7.2), 174 (33), 158 (14), 75 (100); IR (CHCl3) 2915, 1729, 1130, 1065 cm −1 ; Anal. Calcd for C11H23NO4 (233.30): C, 56.63; H, 9.94; N, 6.00. Found: C, 57.49; H, 9.90; N, 6.24.
To a suspension of (S,S)-2,3-di-O-acetyl-tartaric anhydride (1 g, 4.7 mmol) in dry DCM (4.5 ml) was added, at 0° C. and under a nitrogen atmosphere, a solution of compound of formula (III), where R=Leu side chain, (1 g, 4.7 mmol) in dry DCM (2.5 ml). The reaction mixture was stirred at room temperature overnight. After evaporation of the solvent, the crude product of formula (IV), where R=Leu side chain, was dissolved in MeOH (8 ml) and thionyl chloride (292 μl 4 mmol) was added dropwise at 0° C. The mixture was then allowed to reach 60° C. and stirred for 2 h. The solvent was removed and the crude compound of formula (V), where R=Leu side chain, was isolated as a yellow oil and used without further purification in the next step.
A solution of (V), where R=Leu side chain, (1.63 g, 4.7 mmol) in toluene (8 ml) was quickly added to a refluxing suspension of SiO2/H2SO4 (1 g) in toluene (12 ml). The mixture was allowed to react for 30 min, and then one-third of the solvent was distilled off. The hot reaction mixture was filtered through a pad of NaHCO3 and, after evaporation of the solvent, the crude product was purified by flash chromatography (silica gel, EtOAc/P.E. 1:2) affording (VI), where R=Leu side chain, as a white solid (730 mg, 50% yield over three steps).
[α] D 24 22.0 (c 1.0, MeOH); 1 H-NMR (CDCl3, 200 MHz): δ 5.88 (d, J=2 Hz, 1H), 5.09 (t, J=8 Hz, 1H), 4.87 (s, 1H), 4.59 (s, 1H), 3.72 (s, 3H), 3.64 (s, 3H), 3.50 (dd, J 1 =12 Hz, J 2 =2 Hz, 1H), 3.11 (dd, J 1 =12 Hz, J 2 =2 Hz, 1H), 1.67-1.60 (m, 2H), 1.46-1.32 (m, 1H), 0.88 (s, 3H), 0.84 (s, 3H); 13 C-NMR (CDCl3, 200 MHz): δ 170.8 (s), 168.7 (s), 165.6 (s), 100.0 (d), 77.8 (d), 77.3 (d), 52.8 (d), 52.4 (q), 52.3 (q), 48.1 (t), 36.6 (t), 24.7 (d), 23.3 (q), 21.3 (q); MS m/z 315 (11), 256 (100), 240 (4); Anal. Calcd for C14H21NO7 (315.33): C, 53.33; H, 6.71; N, 4.44. Found: C, 52.99; H, 5.58; N, 4.79.
A solution containing (VI), where R=Leu side chain, (1 g, 3.2 mmol) and piperidine (6.3 ml, 63 mmol) was stirred at 60° C. overnight. The reaction mixture was then concentrated under reduced pressure, and the crude product was purified by column chromatography (silica gel, DCM/MeOH 20:1) to afford compound of formula (VII), where R=Leu side chain, R3 and R4=—CH2(CH2)3CH2- (corresponding to compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2(CH2)3CH2-), as a yellow oil (816 mg, 70% yield).
[α] D 22 33.6 (c 1.0, CHCl 3 ); 1 H-NMR (CDCl3, 200 MHz): (mixture of two rotamers) δ 5.79 (d, 1H, J=1.4 Hz), 5.06-4.94 (m, 1H), 5.02 (s, 1H), 4.82 (s, 1H, minor), 4.71 (s, 1H, major), 3.62 (s, 3H, minor), 3.61 (s, 3H, major), 3.55-3.20 (m, 5H), 3.09 (d, J=11.8 Hz, 1H), 1.67-1.34 (m, 9H), 0.86 (d, J=4.8 Hz, 3H), 0.84 (d, J=5.8 Hz, 3H); 13 C-NMR (CDCl3, 200 MHz) (mixture of two rotamers): δ 171.1 (s, minor), 170.8 (s, major), 167.6 (s, minor), 166.8 (s, major), 164.9 (s, minor), 164.8 (s, major), 99.6 (d, major), 99.5 (d, minor), 78.0 (d), 76.4 (d), 52.7 (q), 52.4 (d, major), 52.2 (d, minor), 48.6 (t, major), 47.7 (t, minor), 46.4 (t), 43.5 (t), 36.7 (t, major), 35.8 (t, minor), 26.4 (t), 25.5 (t), 24.7 (d), 24.5 (t), 23.2 (q), 21.5 (q); MS m/z 368 (M+), 309 (21), 312 (100); IR (CHCl3) 2935, 1739, 1666 cm −1 . Anal. Calcd. for C18H29N3O6 (368.43): C, 58.68; H, 7.66; N, 7.60. Found: C, 57.06; H, 7.50; N, 8.32
Example 2
(2S)-2-[(1R,5S,7S)-7-(4-methyl-piperazine-1-carbonyl)-2-oxo-6,8-dioxa-3-aza-bicyclo[3.2.1]oct-3-yl]-4-methyl-pentanoic acid methyl ester [compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(CH3)CH2CH2-]
Compound (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(CH3)CH2CH2- was prepared according to the procedure described for compound (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2(CH2)3CH2-, starting from compound (VI), where R=Leu side chain, (150 mg, 0.48 mmol) and 1-methyl piperazine (1.06 ml, 9.5 mmol). Pure compound (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(CH3)CH2CH2-, (128 mg, 72% yield) was obtained as yellow oil.
[α] D 25 28.1 (c 0.9, CHCl3); 1 H-NMR (CDCl3, 200 MHz): δ 5.85 (s, 1H), 5.12 (s, 1H), 5.05 (t, J=8 Hz, 1H), 4.77 (s, 1H), 3.68 (s, 3H), 3.62-3.51 (m, 5H), 3.14 (d, J=12 Hz, 1H), 2.42-2.33 (m, 4H), 2.72 (s, 3H), 1.73-1.65 (m, 2H), 1.49-1.42 (m, 1H), 0.92 (d, J=6 Hz, 3H), 0.90 (d, J=4 Hz, 3H); 13 C-NMR (CDCl3, 200 MHz): δ 170.8 (s), 166.8 (s), 165.0 (s), 99.7 (d), 78.0 (d), 76.4 (d), 55.0, 54.6 (t), 52.8 (q), 52.5 (d), 48.6 (t), 46.1 (q), 45.4 (t), 42.3 (t), 36.9 (t), 24.8 (d), 23.3 (q), 21.6 (q); MS m/z 383 (23), 352 (2.4), 324 (9), 99 (55), 70 (100); IR(CHCl3) 2866, 1738, 1670 cm −1 ; Anal. Calcd. for C18H29N3O6 (383.44): C, 56.38; H, 7.62; N, 10.96. Found: C, 55.12; H, 6.88; N, 12.01.
Example 3
4′-Methyl-(2′S)-2′-[(1R,5S,7S)-7-(morpholine-4-carbonyl)-2-oxo-6,8-dioxa-3-aza-bicyclo[3.2.1]oct-3-yl]-pentanoic acid methyl ester [compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2OCH2CH2-]
Compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2OCH2CH2- was prepared according to the procedure described for compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2(CH2)3CH2-, starting from compound (VI), where R=Leu side chain, (100 mg, 0.32 mmol) and morpholine (0.55 ml, 6.3 mmol). Pure compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2OCH2CH2- (95 mg, 65% yield) was obtained as a yellow oil.
[α] D 22 29.0 (c 1.0, CHCl3); 1 H-NMR (CDCl3, 200 MHz): δ 5.86 (d, J=2 Hz, 1H), 5.16 (s, 1H), 5.06 (dd, J 1 =J 2 =8 Hz, 1H), 4.76 (s, 1H), 3.70 (s, 3H), 3.67-3.52 (m, 9H), 3.15 (d, J=12 Hz, 1H), 1.75-1.67 (m, 2H), 1.53-1.43 (m, 1H), 0.94 (d, J=6 Hz, 3H), 0.92 (d, J=6 Hz, 3H); 13 C-NMR (CDCl3, 200 MHz): δ 170.8 (s), 99.8 (d), 84.6 (d), 78.0 (d), 66.8 (t), 66.6 (t), 52.8 (q), 52.5 (d), 48.6 (t), 46.0 (t), 42.7 (t), 36.8 (t), 24.8 (d), 23.3 (q), 21.6 (q); MS m/z 370 (14), 311 (60), 283 (19), 168 (100); IR (CHCl3) 2932, 1735, 1668 cm −1 ; Anal. Calcd for C17H26N2O7 (370.41): C, 55.13; H, 7.08; N, 7.56. Found: C, 54.27; H, 6.40; N, 7.22.
Example 4
(2S)-2-[(1R,5S,7S)-7-(4-benzyl-piperazine-1-carbonyl)-2-oxo-6,8-dioxa-3-aza-bicyclo[3.2.1]oct-3-yl]-4-methyl-pentanoic acid methyl ester [compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(benzyl)CH2CH2-]
Compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(benzyl)CH2CH2- was prepared according to the procedure described for compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2(CH2)3CH2-, starting from compound of formula (VI), where R=Leu side chain, (100 mg, 0.32 mmol) and 1-benzyl piperazine (1.1 ml, 6.3 mmol). Pure compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(benzyl)CH2CH2- (106 mg, 72% yield) was obtained as a yellow oil.
[α] D 23 20.1 (c 1.1, CHCl3); 1 H-NMR (CDCl3, 200 MHz): δ 7.42-7.27 (m, 5H), 5.88 (s, 1H), 5.25-5.05 (m, 2H), 4.79 (s, 1H), 3.71 (s, 3H), 3.63-3.53 (m, 7H), 3.16 (d, J=11.6 Hz, 1H), 2.51-2.45 (m, 4H), 1.76-1.68 (m, 2H), 1.55-1.25 (m, 1H), 0.96 (d, J=5, 3H), 0.93 (d, J=6.2 Hz, 3H); 13 C-NMR (CDCl3, 200 MHz): δ 170.8 (s), 166.8 (s), 165.0 (s), 129.1 (d), 128.3 (d), 127.3 (d), 99.7 (d), 78.0 (d), 76.4 (d), 62.9 (t), 52.9 (q), 52.7, 52.7 (t), 52.5 (d), 48.5 (t), 45.5, 42.4 (t), 36.8 (t), 24.8 (d), 23.3 (q), 21.6 (q); MS m/z 459 (10), 400 (1), 330 (1), 175 (19), 91 (100); IR(CHCl3) 2940, 1740, 1672 cm −1 ; Anal. Calcd for C24H33N3O6 (459.55): C, 62.73; H, 7.24; N, 9.14. Found: C, 61.34; H, 6.82; N, 8.50.
Example 5
(2S)-2-[(1R,5S,7S)-7-(4-phenylethyl-piperazine-1-carbonyl)-2-oxo-6,8-dioxa-3-aza-bicyclo[3.2.1]oct-3-yl]-4-methyl-pentanoic acid methyl ester [compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(—CH2CH2Ph)CH2CH2-]
Compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(—CH2CH2Ph)CH2CH2- was prepared according to the procedure described for compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2(CH2)3CH2-, starting from compound of formula (VI), where R=Leu side chain, (100 mg, 0.32 mmol) and 1-phenylethyl piperazine (1.2 ml, 6.3 mmol). Pure compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2CH2N(—CH2CH2Ph)CH2CH2- (89 mg, 59% yield) was obtained as a yellow oil.
[α] D 25 21.3 (c 0.9, CHCl 3 ); 1 H-NMR (CDCl3, 200 MHz): δ 7.33-7.18 (m, 5H), 5.88 (d, J=2 Hz, 1H), 5.17 (s, 1H), 5.09 (dd, J 1 =8 Hz, J 2 =6 Hz, 1H), 4.81 (s, 1H), 3.72 (s, 3H), 3.78-3.63 (m, 4H), 3.57 (dd, J 1 =12 Hz, J 2 =2 Hz, 1H), 3.18 (d, J=12 Hz, 1H), 2.88-2.80 (m, 2H), 2.70-2.58 (m, 6H), 1.78-1.70 (m, 2H), 1.53-1.25 (m, 1H), 0.98 (d, J=6 Hz, 3H), 0.94 (d, J=6 Hz, 3H); 13 C-NMR (CDCl3, 200 MHz): δ 170.6 (s), 166.5 (s), 164.8 (s), 138.5 (s), 128.4 (d), 128.3 (d), 126.1 (d), 99.5 (d), 77.7 (d), 76.9 (d), 59.5 (t), 52.6 (q), 52.4, 52.2 (t), 51.9 (d), 48.2, 44.3 (t), 41.3 (t), 36.5 (t), 32.4 (t), 24.4 (d), 22.8 (q), 21.2 (q); MS m/z 414 (1), 382 (95), 56(100); IR (CHCl 3 ) 2923, 1740, 1672 cm −1 ; Anal. Calcd. for C25H35N3O6 (473.57): C, 63.41; H, 7.45; N, 8.87. Found: C, 62.28; H, 7.01; N, 8.96.
Example 6
(2S)-4-Methyl-2-[(1R,5S,7S)-2-oxo-7-(piperidine-1-carbonyl)-6,8-dioxa-3-aza-bicyclo[3.2.1]oct-3-yl]-pentanoic acid (3-butylcarbamoyl-2-hydroxy-propyl)-amide [compound of formula (I), where R1=—CH(Leu side chain)COR5, R2=H, R3 and R4=—CH2CH2OCH2CH2-, R5=—NHCH2CH(OH)CH2CONHBu]
To a solution of 4-amino-3-hydroxy-butyric acid methyl ester hydrochloride salt, (37 mg, 0.22 mmol) in DCM (4 ml) were added, under a nitrogen atmosphere and at 0° C., PyBrOP (102 mg, 0.22 mmol), (2S)-4-methyl-2-[(1R,5S,7S)-2-oxo-7-(piperidine-1-carbonyl)-6,8-dioxa-3-aza-bicyclo[3.2.1]oct-3-yl]-pentanoic acid (80 mg, 0.22 mmol), previously obtained by basic ester hydrolysis of compound of formula (I), where R1=—CH(Leu side chain)COOCH3, R2=H, R3 and R4=—CH2(CH2)3CH2-, with LiOH, and DIPEA (85 μl, 0.5 mmol). The resulting solution was allowed to reach room temperature and was stirred overnight. The reaction mixture was then washed with a saturated solution of NaHCO3, aqueous 5% KHSO4, brine and dried over Na 2 SO 4 . After evaporation of the solvent the crude product was diluted in EtOAc and left for three hours at 4° C. in order to allow precipitation of the PyBrOP. After purification by flash chromatography, the resulting compound (40 mg, 0.08 mmol) was treated with n-butyl amine (168 μl, 1.7 mmol) in a mixture of THF (200 μl) and two drops of H2O at 50° C. for three days. Filtration of the reaction mixture on Amberlyst 15 and further purification by column chromatography (silica gel, DCM/MeOH 20:1) afforded 30 mg of compound of formula (I), where R1=—CH(Leu side chain)COR5, R2=H, R3 and R4=—CH2CH2OCH2CH2-, R5=—NHCH2CH(OH)CH2CONHBu as a colourless oil.
1 H-NMR (CDCl3, 200 MHz): δ 6.81-6.68 (m, 1H), 6.41-6.22 (m, 1H), 5.90, 5.86 (s, 1H, mixture of two diastereoisomers), 5.14-4.81 (m, 3H), 4.13-3.92 (m, 1H), 3.66-3.35 (m, 6H), 3.36-3.02 (m, 4H), 2.28 (d, J=5.2 Hz, 2H), 1.88-1.20 (m, 13H), 0.97-0.87 (m, 9H); 13 C-NMR (CDCl3, 200 MHz): δ 171.5 (s), 170.2 (s), 168.0 (s), 164.8 (s), 99.6 (d), 77.9 (d), 67.9 (d), 54.1, 53.9 (d), 47.6 (t), 46.6 (t), 44.5 (t), 43.6 (t), 39.4 (t), 36.4 (t), 34.9 (t), 31.6 (t), 26.4 (t), 25.6 (t), 24.9 (d), 24.6 (t), 23.1 (q), 22.0 (q), 20.3 (t), 13.9 (q); MS m/z 510 (3), 309 (34), 112 (69), 84 (100).
The following examples are reported to give a non-limiting illustration of the in vitro and in vivo activity of selected compounds of the present invention.
Protease Enzyme Assay
Spectrophotometric method: protease activity of the various compounds of formula (I) was measured by a spectrophotometric assay with respect to pepstatin activity at the same concentration: each assay contained 50 μl of sample in 0.4 ml of 1% (w/v) BSA in 50 mM sodium citrate pH 3.2 and 50 μl of protease solution (1 μg/ml) After 30 min at 37° C. 1 ml 10% (w/v) trichloroacetic acid was added. The tubes were stored in ice for 30 min, and then centrifuged (3000 g) for 10 min. The absorbance of the supernatant was read at 280 nm. Control: 1% BSA in citrate buffer. One unit of the enzyme catalysed a ΔA 280 of 1 min −1 . With the pure protease the assay was proportional to enzyme concentration over the range ΔA 280 0.1-0.4 and a limit detection of 1 μg (De Bernardis F., Sullivan P. A., Cassone A. Medical Mycology 2001, 39, 303).
TABLE 1 In vitro activity towards SAP2 of representative compounds of the present invention. 1% is the percent of inhibition with respect to pepstatin at the same concentration of 10 μm. (I) Cpd R1 R2 R3 R4 R5 1% 1 —CH(Leu side chain)COR5 H —CH2(CH2)3CH2— OCH3 37 2 —CH(Leu side chain)COR5 H —CH2CH2OCH2CH2— OCH3 32 3 —CH(Leu side chain)COR5 H —CH2(CH2)3CH2— NHCH2CH(OH) 22 CH2CONHBu 4 —CH2Ph H H —CH2CH2OH — 36 5 —CH2Ph H H —CH(Leu side chain)CH2OH — 41 6 —CH2Ph H —CH2(CH2)3CH2— — 42 7 —CH2Ph H —(CH2)2NCH2CH2OH(CH2)2— — 34 8 —CH2Ph H —CH2CH2OCH2CH2— — 31 9 —CH2Ph H —CH2CH2NC(O)OCH2CH3CH2CH2— — 37 10 —CH2Ph H H —(CH2)3OH — 12 11 —CH2Ph H H —CH(Pro side chain)CH2OH — 24 12 —CH2Ph H H —CH(D-Pro side chain)CH2OH — 17 13 —CH2Ph H H —CH(Phg side chain)CH2OH — 16 14 —CH2Ph H H —CH(Phe side chain)CH2OH — 19 15 —CH2Ph H H —CH(D-Phe side chain)CH2OH — 15 16 —CH2Ph —CH2Ph H —(CH2)3CH3 — 17 17 —CH2Ph —CH2Ph H —(CH2)5CH3 — 21 18 —CH2Ph —CH2Ph H —CH2CF3 — 17 19 —CH2Ph —CH2Ph —CH2CH2OCH2CH2— — 25 20 —CH2Ph —CH2Ph —CH2CH2SCH2CH2— — 28 21 —CH2Ph —CH2Ph —(CH2)2NCH2CH2OH(CH2)2— — 31
In Vivo Assay
Experimental vaginal infection: for the experimental vaginal infection, a previously described rat vaginal model was adopted (De Bernardis, F.; Boccanera, M.; Adriani, D.; Spreghini, E.; Santoni, G.; Cassone, A. Infect. Immun., 1997, 65, 3399).
In brief, oophorectomized female Wistar rats (80-100 g; Charles River Calco, Italy) were injected subcutaneously with 0.5 mg of estradiol benzoate (Estradiolo, Amsa Farmaceutici srl, Rome, Italy). Six days after the first estradiol the animals were inoculated intravaginally with 107 yeast cells in 0.1 ml of saline solution of each C. albicans strain tested. The inoculum was dispensed into the vaginal cavity through a syringe equipped with a multipurpose calibrated tip (Combitip; PBI, Milan, Italy). The yeast cells had been previously grown in YPD broth (yeast extract 1%; peptone 2%; dextrose 2%) at 28° C. on a gyrator shaker (200 rpm), harvested by centrifugation (1500 g), washed, counted in a hemocytometer, and suspended to the required number in saline solution. The number of cells in the vaginal fluid was counted by culturing 100 μl samples (using a calibrated plastic loop, Disponoic, PBI, Milan, Italy) taken from each animals, on Sabouraud agar containing chloramphenicol (50 μg/ml) as previously described. The rat was considered infected when at least 1 CFU was present in the vaginal lavage, i.e. a count of >103 CFU/ml.
As a representative example for in vivo studies, one of the compounds of formula (I), as above described and hereinafter named APG12, corresponding to compound 6 of Table 1, was administered intravaginally at concentrations of 10 μM 1 h, 24 h and 48 h after intravaginal Candida albicans challenge with two different strains, namely SA40 and the pharmacoresistant AIDS68. Positive (pepstatin 10 μg; fluconazole 10 μg and negative (sterile saline solution) were similarly administered.
The profile of Candida albicans clearance in rats intravaginally treated with APG12 is similar to the acceleration observed in rats treated with the natural SAP2 inhibitor pepstatin, and in rats treated with fluconazole (Table 2 and FIG. 1 ). More importantly, the acceleration of Candida albicans clearance in the pharmacoresistant AIDS68 strain shows efficacy of both the natural SAP2 inhibitor pepstatin and of APG12, whereas the fluconazole is ineffective, showing a clearance profile similar to the untreated control (Table 3 and FIG. 2 ).
TABLE 2
Acceleration of Candida SA40 clearance in rats intravaginally treated with
APG12 after challenge (1, 24, 48 hrs)
SA40 +
DAYS
SA40 + APG12
pepstatin
SA40
0
>100
>100
>100
1
70 ± 1.3
56.8 ± 2
>100
2
57.6 ± 1.4
51 ± 1.2
>100
5
39.2 ± 3
32.4 ± 2.5
80 ± 2.6
7
30.6 ± 1.8
28 ± 1.5
66 ± 2.1
14
14.4 ± 1.6
9.4 ± 1.4
26.2 ± 1.8
21
8 ± 1.5
5 ± 1.3
12.8 ± 1.2
28
1.2 ± 0.7
0
5.8 ± 1.6
All values×1000; SA40: untreated control; Starting day 1, all differences between APG12-treated and untreated control are statistically significant; (P<0.01, Mann-withney U test)
TABLE 3
Acceleration of Candida AIDS68 clearance in rats intravaginally treated
with APG12 after challenge (1, 24, 48 hrs)
AIDS68 +
AIDS68 +
AIDS68 +
DAYS
APG12
pepstatin
fluconazole
AIDS68
0
>100 ± 0
>100 ± 0
>100 ± 0
>100 ± 0
1
71.8 ± 1.3
58.4 ± 1.0
100 ± 0
100 ± 0
2
62.6 ± 1.5
52.0 ± 1.3
93 ± 4.3
100 ± 0
5
40.6 ± 1.4
37.2 ± 1.6
61 ± 2.5
71 ± 1.6
7
23.2 ± 1.4
30.0 ± 1.2
44 ± 2.9
50 ± 3.5
14
12.8 ± 1.2
19.8 ± 0.8
18.7 ± 3.8
25 ± 1.6
21
3.4 ± 1.7
3.8 ± 1.9
11.7 ± 0.7
10.7 ± 1.6
28
0 ± 0
0 ± 0
0 ± 0
7.7 ± 3
All values×1000; AIDS68: untreated control; Starting day 1, all differences between APG12-treated and untreated control are statistically significant; (P<0.01, Mann-withney U test) | The present invention refers to 3-aza-bicyclo [3.2.1] octane derivatives of general formula (I) their preparation, use and pharmaceutical compositions useful in the treatment of pathologies associated with microbial pathogens expressing aspartylprotease activity. | 2 |
TECHNICAL FIELD
[0001] The invention relates to a vehicle accessory drive system having a torque-transmitting mechanism to selectively connect an engine to an accessory. The invention also relates to a method of controlling the speed of a driven accessory.
BACKGROUND OF THE INVENTION
[0002] Vehicle accessories such as air conditioning systems, power steering systems and water pumps are typically driven directly by the engine crankshaft through, for example, a belt and pulley system. Therefore, the accessories must be capable of operating over the entire speed range of the engine, as the operating speeds of the accessories in a conventional drive system are directly proportional to the speed of the engine. The accessories are therefore typically designed to provide full capacity when the engine is operating at the low end of the engine speed range, because the accessories must be designed to give sufficient performance at low speeds, such as during engine idle, as well as being capable of running at high speeds during engine maximum speed operation. At higher engine speeds, excess energy is transferred to the accessories that may be lost.
SUMMARY OF THE INVENTION
[0003] A speed-limiting accessory drive system is provided that limits the speed range over which one or more engine-driven accessories operate while maintaining the operating speed range of the engine. A speed-limiting accessory drive system includes an engine and a battery as well as a drive motor operatively connected with the battery. At least one driven accessory is operatively connected with the drive motor. A torque-transmitting mechanism is selectively engageable to operatively connect the engine with the accessory. An engine speed sensor is operable to monitor the speed of the engine. A controller is operatively connected to the torque-transmitting mechanism, to the engine speed sensor and to the drive motor. The controller is configured to maintain the torque-transmitting mechanism in an engaged state only when the monitored engine speed is within a predetermined speed range and to control the drive motor to drive the driven accessory when the monitored engine speed is not within the predetermined range. Preferably, the predetermined speed range at which the controller maintains the torque-transmitting mechanism in an engaged state is calculated based upon the optimal speed range of the driven accessory. When the controller disengages the torque-transmitting mechanism, the controller can control the drive motor to supply torque such that the accessory is driven at a speed by the motor within an optimal speed range for the accessory. Preferably, the speed-limiting accessory drive system is part of a powertrain that includes the engine and an electromechanical transmission.
[0004] The speed-limiting accessory drive system may drive multiple driven accessories, in which case selective engagement of the torque-transmitting mechanism operatively connects the engine and the multiple accessories, potentially at different relative speeds. This may be accomplished by a belt and pulley torque transfer arrangement wherein different size pulleys are operatively connected with the different accessories. Alternatively, a chain and sprocket torque transfer arrangement may be used.
[0005] Preferably, the torque-transmitting mechanism is configured for operation as both an overrunning clutch and an underrunning clutch. Thus, if the engine output member (e.g., an engine crankshaft) is running at a speed below the predetermined speed range, the torque-transmitting mechanism is overrunning, i.e., the portion of the torque-transmitting mechanism operatively connected with the driven accessory is rotating faster than the portion of the torque-transmitting mechanism operatively connected with the engine. Preferably, the torque-transmitting mechanism may also operate as an underrunning clutch when the engine is running at a speed above the predetermined speed range. In this case, the portion of the clutch operatively connected with the engine is rotating faster than the portion of the clutch operatively connected with the accessories.
[0006] A method of controlling the speed of at least one driven accessory, which may be carried out using the speed-limiting accessory drive system, includes providing a drive motor adapted for driving the driven accessory as well as a torque-transmitting mechanism that is selectively engageable to operatively connect the engine with the driven accessory. The method further includes monitoring whether the torque-transmitting mechanism is in an engaged state or a disengaged state. The method includes monitoring speed of the engine and comparing monitored engine speed to a predetermined range of speeds. Finally, the method includes controlling the drive motor as well as engagement of the torque-transmitting mechanism such that the driven accessory is driven by the engine if monitored speed is within the predetermined range and is driven by the drive motor if monitored engine speed is not within the predetermined range.
[0007] The predetermined range of speeds may be from a predetermined minimum speed to a predetermined maximum speed, including both the predetermined minimum and predetermined maximum speeds. Preferably, the predetermined minimum speed and the predetermined maximum speed are calculated based on an optimal speed range for operation of the driven accessory. In this case, any speed multiplier or speed reduction in the torque transfer arrangement (e.g., the belt and pulley or chain and sprocket system) between the engine and the driven accessory is accounted for in determining the minimum and the maximum speeds.
[0008] There are four different possible modes determined under the monitoring steps. In a first mode, the monitored engine speed is not less than the predetermined minimum speed and not greater than the predetermined maximum speed and the torque-transmitting mechanism is in the engaged state. In this first mode, the torque-transmitting mechanism is maintained in the engaged state so that the driven accessory is driven by the engine.
[0009] In a second mode, the monitored engine speed is not less than the predetermined minimum speed and not greater than the predetermined maximum speed and the torque-transmitting mechanism is in the disengaged state. In this second mode, the controlling step includes engaging the torque-transmitting mechanism so that the driven accessory is driven by the engine.
[0010] In a third mode, monitored engine speed is less than the predetermined minimum speed or is greater than the predetermined maximum speed and the torque-transmitting mechanism is in the engaged state. In this third mode, the controlling step includes disengaging the torque-transmitting mechanism and controlling the motor so that the driven accessory is driven by the motor at a speed that is not less than the predetermined minimum speed and not greater the predetermined maximum speed.
[0011] Finally, in a fourth mode, the monitored engine speed is less than the predetermined minimum speed or greater than the predetermined maximum speed and the torque-transmitting mechanism is in the disengaged state. In this fourth mode, the disengaged state of the torque-transmitting mechanism is maintained and the motor is controlled so that the driven accessory is driven by the motor at a speed not less than the predetermined minimum speed and not greater than the predetermined maximum speed.
[0012] Accordingly, the speed-limiting accessory drive system and the method of control described herein limit the minimum and maximum drive speed of the accessory without limiting the operating speed range of the engine. Thus, the accessory design and size can be based upon the smaller operating speed range (the range between and including the predetermined minimum and maximum speeds) rather than the operating speed range of the engine, which is likely to be a much broader range.
[0013] The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic illustration of a vehicle having a speed-limiting accessory drive system within the scope of the invention; and
[0015] FIG. 2 is a flow chart illustrating a method of controlling the speed of at least one driven accessory.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] Referring to the drawings wherein like reference numerals refer to like components, in FIG. 1 a vehicle 10 is shown schematically. The vehicle 10 has a powertrain 12 to drive the wheels (not shown) of the vehicle 10 . The powertrain 12 includes an engine 14 which is operatively connected to a transmission input member 16 of a transmission 18 . The transmission 18 provides power at various speed ratios to the output member 19 . In this embodiment, the transmission 18 is a hybrid electromechanical transmission having first and second motor/generators 20 , 22 , respectively, that may function as either motors or generators. The first motor/generator 20 is in an input-split arrangement with the engine 14 as both are connected to different elements of the first gearing arrangement 24 . The second motor/generator 22 is in an output-split arrangement in that it is connected to an element of a second gearing arrangement 26 . The motor/generators 20 , 22 function as motors by receiving power from an electrical power source 30 , such as a battery. A controller 32 is operatively connected to the battery 30 through a power inverter module 34 . The power inverter module 34 includes separate power inverters, one operatively connected to the motor/generator 20 , one operatively connected to the motor/generator 22 , as well as one operatively connected to a drive motor 70 (discussed below). The controller 32 causes the power inverter module 34 to provide power received from the battery 30 to either or both of the motor/generators 20 , 22 so that the motor/generators 20 , 22 may provide torque through the respective gearing arrangements 24 , 26 . If the motor/generators 20 , 22 are to function as generators, the controller 32 controls them to receive power from the respective gearing arrangements 24 , 26 . Those skilled in the art will readily understand the functional operation of a hybrid transmission. It should be appreciated that, although a hybrid electrically variable transmission is illustrated, a non-hybrid manual or automatic transmission may be used within the scope of the invention.
[0017] A speed-limiting accessory drive system 40 allows the engine 14 to selectively drive multiple accessories, accessory 42 , accessory 44 , and accessory 46 . The accessories may include but are not limited to a power steering pump, a water pump and an air conditioning compressor. The first accessory 42 is a power steering pump, the second accessory 44 is a water pump, and the third accessory is an air conditioning compressor, for purposes of illustration.
[0018] The speed-limiting accessory drive system 40 includes a torque-transmitting mechanism 48 which is preferably a rotating friction clutch. The torque-transmitting mechanism 48 is selectively engageable under the control of controller 32 through hydraulic, electric or other communication means to connect a crankshaft 50 of engine 14 with an accessory drive shaft 52 . A rotatable member 54 is connected for common rotation with the accessory drive shaft 52 . A torque-transmitting arrangement 53 connects the rotatable member 54 such that rotation of the rotatable member 54 drives the accessories, 42 , 44 and 46 . The torque-transmitting arrangement 53 includes rotatable members 56 , 58 and 60 connected for common rotation with drive shafts 62 , 64 and 66 , respectively, of the accessories 42 , 44 and 46 . An endless rotation transferring device 68 connects the rotatable member 54 with the rotatable members 56 , 58 and 60 such that the rotation of the rotatable member 54 may cause rotation of the other rotatable members 56 , 58 and 60 via the endless rotation transferring device 68 . Within the scope of the invention, the rotatable members 54 , 56 , 58 and 60 may be pulleys and the rotation transferring device 68 may be an endless belt. Alternatively, within the scope of the invention, the rotatable members 54 , 56 , 58 and 60 may be sprockets and the rotation transfer device 68 may be a chain. It should be appreciated, that the rotatable members 54 , 56 , 58 and 60 may have different radial dimensions so that the rotation transfer device causes rotation of the respective drive shaft 62 , 64 , 66 at different relative speeds.
[0019] The speed-limiting accessory drive system 40 also includes an electric drive motor 70 operatively connected with the accessories 42 , 44 and 46 via an electric drive motor shaft 72 and rotatable member 74 that is also operatively connected to the rotatable members 56 , 58 and 60 through the rotation transfer device 68 . The controller 32 controls operation of the electric drive motor 70 through another power inverter included in the power inverter module 34 , commanding it to spin freely with rotation of the rotatable member 74 or commanding it to provide torque to drive the rotatable member 74 . Specifically, the controller 32 is configured with a stored algorithm that controls the engagement of the torque-transmitting mechanism 48 between an engaged state in which the engine 14 may drive the accessories 42 , 44 , 46 via the torque-transmitting arrangement 53 and a disengaged state in which the controller drives the accessories 42 , 44 , 46 via the electric drive motor 70 so that the electric drive motor 70 , acts as a motor providing torque through the torque-transmitting arrangement 53 .
[0020] The speed-limiting accessory drive system 40 includes a sensor 78 operatively connected to the engine crankshaft 50 and to the controller 32 (transfer conductors connecting the sensor 78 with the controller 32 not shown for purposes of simplicity in the drawing). The sensor 78 senses speed of the crankshaft 50 and provides this information to the controller 32 . The speed-limiting accessory drive system 40 also includes a sensor 80 operatively connected to the controller 32 and to the accessory drive shaft 52 that enables the controller 32 to determine whether the torque-transmitting mechanism 48 is in an engaged state or a disengaged state. For example, the sensor 80 may be a strain gauge connected with the accessory drive shaft 52 .
[0021] Referring to FIG. 2 , an algorithm within the controller controls the speed-limiting accessory drive system 40 according to the method 100 illustrated in the flow chart of FIG. 2 . The method 100 includes step 102 , providing a drive motor adapted for driving at least one accessory. Method 100 also includes step 104 , providing a torque-transmitting mechanism that is selectively engageable to operatively connect an engine with the accessory. The method 100 further includes step 106 , monitoring speed of the engine. After step 106 , the method 100 includes step 108 , comparing the monitored engine speed with a predetermined range of speeds. This preferably includes determining whether the engine speed is greater than or equal to a predetermined minimum speed and also whether the engine speed is less than or equal to a predetermined maximum speed. The predetermined minimum speed and the predetermined maximum speed may be based upon the optimal operating speed of the accessory or accessories. For example, the optimal operating speed ranges of the first, second and third accessories, 42 , 44 and 46 can be stored within the controller 32 . The accessory having the greatest lower minimum speed is used by the controller 32 to determine minimum speed. The accessory having the lowest upper maximum speed may be used by the controller 32 to determine the maximum speed. Based on the determination of step 108 , under step 109 , the controller 32 controls power to the drive motor 72 and engagement of the torque-transmitting mechanism 48 so that the accessories 42 , 44 and 46 are driven by the engine 14 if the engine speed is within the predetermined range of speeds and is driven by the drive motor 70 if monitored engine speed is not within the predetermined range of speeds.
[0022] If it is determined in step 108 that the engine speed is within the predetermined range, then step 109 includes step 110 A in which the controller 32 determines whether the torque-transmitting mechanism 48 is engaged. If the torque-transmitting mechanism 48 is engaged, then it continues to be maintained in the engaged state, as this is the most optimal manner for driving the accessories 42 , 44 and 46 . The method 100 then continues to monitor engine speed under step 108 . However, if it is determined in step 110 A that the torque-transmitting mechanism 48 is not engaged, then the method 100 moves to step 114 , engaging the torque-transmitting mechanism 48 . The engaging step 114 , thus occurs during a first mode of operating conditions in which the engine 14 is determined to be within a predetermined speed range so that the controller 32 allows the engine 14 to drive the accessories 42 , 44 and 46 . The method 100 then continues to monitor the engine speed under step 108 .
[0023] If in step 108 it is determined that the monitored engine speed is not within the predetermined range, then step 109 includes step 110 B (which is comparable with step 110 A), determining whether the torque-transmitting mechanism 48 is engaged. If the torque-transmitting mechanism 48 is determined to be engaged, method 100 then includes disengaging torque-transmitting mechanism 48 in step 116 and powering the motor 70 in step 118 so that the motor 70 drives the accessories 42 , 44 , 46 at a speed within an optimal range for the accessories 42 , 44 , 46 . If in step 108 it is instead determined that the monitored engine speed is not within the predetermined range and under step 110 B it is determined that the torque-transmitting mechanism 48 is not engaged, the method 100 goes directly to step 118 in which the controller 32 controls power to the motor 70 to drive the accessories within the optimal speed range.
[0024] Thus, in a first mode of operating conditions in which engine speed is within the predetermined range, under step 108 , the controller 32 will determine that the engine speed is within the predetermined range (i.e., it is greater than or equal to the predetermined minimum speed and less than or equal to the predetermined maximum speed). In this instance, step 110 A will result in engaging the torque-transmitting mechanism 48 if it is disengaged via step 114 or maintaining it in the engaged state if it is already engaged so that the engine 14 drives the accessories 42 , 44 and 46 via the torque-transmitting arrangement 53 .
[0025] In a second mode of operating conditions in which the monitored speed of the engine is zero, such as when the engine is turned off and the vehicle 10 is being powered by the motor/generators 20 , 22 , the method 100 determines in step 108 that the engine speed is less than the predetermined minimum speed. Under step 110 B, the method 100 determines whether the torque-transmitting mechanism is engaged and, if it is engaged, disengages the torque-transmitting mechanism in step 116 . The method 100 then controls power to the motor 70 under step 118 such that the motor 70 drives the accessories 42 , 44 and 46 .
[0026] In a third operating mode, the monitored engine speed of step 106 is a non-zero value but is less than the predetermined minimum speed. In this instance, after step 108 the controller will move to step 110 B and either disengage the torque-transmitting mechanism 48 in step 116 or move directly to step 118 (if the torque-transmitting mechanism 48 is not engaged) so that power is provided by the motor 70 to drive the accessories 42 , 44 and 46 at a speed within the optimal range.
[0027] Finally, in a fourth operating mode, the monitored engine speed of step 106 is greater than the predetermined maximum speed. Under step 108 , the method 100 will move to step 110 B and, if the torque-transmitting mechanism 48 is engaged, it will be disengaged under step 116 and, whether or not the torque-transmitting mechanism was determined to be engaged under step 110 B, under step 118 power will be provided by the motor 70 to drive the accessories 42 , 44 , 46 within the optimal range for the accessories 42 , 44 and 46 .
[0028] While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims. | A speed-limiting accessory drive system is provided that limits the speed range over which an engine-driven accessory operates while maintaining the operating speed range of the engine. A torque-transmitting mechanism is selectively engagable to operatively connect the engine and the accessory. A controller is configured to maintain the torque-transmitting mechanism in an engaged state only when monitored engine speed is within a predetermined speed range and to control a drive motor to drive the driven accessory when the monitored engine speed is not within the predetermined range. A method of controlling the speed of at least one driven accessory, which may be carried out using the speed-limiting accessory drive system, is also provided. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates to a floating vessel.
BACKGROUND TO THE INVENTION
[0002] Water sports are popular outdoor activities. In recent years new sports such as windsurfing and kite boarding are growing in popularity, compared to traditional sailing. They offer more fun and are more accessible in terms of money and space.
[0003] Mapping the practice of sailing around the targeted use of the boat, we observe that new alternative water sports such as windsurfing and kite surfing are getting more popular and are relatively less expensive than traditional sailing.
[0004] On the other hand these alternative sports have higher access barriers, consisting of training time to learn how to windsurf and kite board. This is the major unique selling point of leisure boats such as rotomoulded catamarans (e.g. the Funboat manufactured by Performance Sailcraft Europe Limited of Northamptonshire, UK, or the Bravo® manufactured by Hobie® of California, USA) which ensure higher stability and have easy boomless rigs.
[0005] Existing boats need to be transported on a trailer or the on top of a car. In this case it is difficult for one person to lift the boat over the top (weight over 50 kg). On the other hand windsurf equipment can be transported on top of or in a car and one person can load and unload it. Furthermore windsurf equipment can be carried on the plane, while that is impossible for boats.
[0006] Based on personal experience and informal exploration with sailors I have focused my attention on small recreational sailboats for one person. This segment represents an important slice of the boating market and ranges from easy leisure boats to racing sail crafts. The common needs expressed by users during the early informal exploration are portability and easy of use. Hence the initial brief:
Sailing fun in a bag: “Create a new sailing experience that enhances the fun of sailing given by the interactions with the elements wind and water and that reduces the hassle associated with assembling, transporting and storing the equipment.”
[0008] The open brief allowed me to investigate in the early stages new forms of sailing and generate hybrid concepts. The choice has been then for a craft that sails like a conventional dinghy but offers more portability and accessibility for new sailors. The project has focused on the boat hull which is the real bulky part of the boat. Moreover, compatibility with existing collapsible sailing rigs, like the windsurf ones, lowers the cost barrier for new users.
[0009] Nowadays the use of a foldable sailing boat responds to very specialized needs. Most foldable boats are designed for fishing, kayak travelling or as emergency dinghies. Some of them have an optional sailing rig offered by third parties. A new product needs to be placed in a wider scenario of water and recreational outdoor sports.
[0010] Direct competitors are the very few collapsible sailing boats and foldable kayaks with custom sailing rigs. Major examples of collapsible sailing crafts are: the Aquaglide®, an inflatable multi-sport craft deriving from windsurfing manufactured by Aquaglide® of Washington, USA (retail price £350); the Stowaway® plywood sailing dinghy manufactured by Stowaway® Boats Ltd of Northamptonshire, UK (£1,000-£2,000); and the Tinker® inflatable with sailing kit manufactured by Henshaw Inflatables Ltd of Somerset, UK (£2,500-3,000). Foldable kayaks are quite popular and their price range is £1,000-£2,500. Small companies offer custom sailing kit for the most popular kayaks (£500-£1,000). The kit comprises boat appendices because of the kayak's poor sailing performance. The most common folding rowboats, mainly used for fishing or as emergency dinghies are probably the polypropylene Portabote® manufactured by Portabote®, California, US (from £1,300) and the aluminium Instaboat® manufactured by Instaboat®, Montmagny, Quebec, Canada (£800). For the first one there is now available an optional sail rig for £600. Finally an entry level sport sailing dinghy has retail prices starting from £1,675 (the Topaz Taz®, manufactured by Topper® of Slough, UK), while the best-selling (the Laser® manufactured by Performance Sailcraft Europe Limited of Northamptonshire, UK, with over 190,000 units worldwide) is £3,500.
[0011] The markets where collapsible sailing boat could compete are:
1. traditional sailing dinghies, by generating an affordable entry level solution, which adds ease of transport and storage. 2. windsurfing, by sharing the same sails and making the switch from one sport to another less expensive. 3. inflatables, by means of providing an easier and quicker assembling system. 4. outdoor “week-end” sports and leisure activities such as skiing, snowboarding, mountain biking, kayaking, thus winning more enthusiasts to the boating sports.
SUMMARY OF THE INVENTION
[0016] This invention provides a floating vessel comprising, in the orientation of use, a central longitudinal member having a vertical height, and to each side of the longitudinal member, an upper substantially laminar panel connected to the longitudinal member and extending outwardly therefrom and a lower substantially laminar panel connected to the longitudinal member at a distance below the upper panel and extending outwardly from the longitudinal member, wherein the outermost edges of the upper and lower panels are connected and the lower panel is larger in the outward direction than the upper panel such that the panels form a stable structure.
[0017] It may be that the outermost edges of the panels are releasably connected. If they are then the panels are releasably connected to the longitudinal member. It may also be that the panels are releasably connected with hook and loop fasteners.
[0018] It may be that the panels are formed of cellular or corrugated plastics material. If this is the case, then the corrugations or cells of the upper panel may run transversely to the corrugations or cells of the lower panels.
[0019] It may be that the longitudinal member comprises an aluminium beam.
[0020] It may be that the vessel is a boat.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] An embodiment of the invention will now be described, by way of example only, and with reference to the accompanying drawings, in which:
[0022] FIG. 1 is a graph showing the righting behaviour of one embodiment of the invention at various angles of heel;
[0023] FIGS. 2 to 7 are pictures showing the process of packing one embodiment of the invention flat;
[0024] FIG. 8 is an illustration of polypropylene after profile rolling according to an embodiment of the invention;
[0025] FIG. 9 is a picture showing the fixing and sealing solution for the external edges of an embodiment of the invention;
[0026] FIGS. 10 to 15 are illustrations of the hull in use with various sails;
[0027] FIG. 16 is an exploded diagram of a hull according to one embodiment of the invention;
[0028] FIGS. 17 to 21 show a hull according to one embodiment of the invention from various angles;
[0029] FIG. 22 shows a hull according to another embodiment of the invention; and
[0030] FIGS. 23 to 25 show three possible hull configurations according to the invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0031] The proposed product is a small boat, designed for leisure sailing and compatible with conventional sailing rigs (windsurf). The main features are the portability and the accessibility that aim to attract new enthusiasts to the boating sports. When needed, it folds to a flat pack with the dimension of windsurfing equipment.
[0032] From the industrial design point of view the key factor of this project is the application of corrugated extruded polypropylene sheet to boat building, using its properties to perform more functions. The folded sheets are at once the boat skin and the structure; they form the living hinges and generate embedded reserve safety buoyancy.
[0033] This product can be a first boat for young people, a leisure boat for families, new sail enthusiasts. It can have a price range much lower than traditional boats and therefore comparable with other popular recreational sport equipment such as high end mountain bike and or a skiing set. To enter the target markets the strategy could be to offer a boat compatible with existing sailing rigs, thus lowering the price barrier to access for existing sailors and newcomers. This would also lower the barrier regarding acceptability and feasibility, with the possibility of partnering with existing known sail brands for delivering complete boats over their distribution channels.
Product Specifications:
[0000]
Crew: 1 adult person, average weight 75 kg
Sailing performance comparable to beginner sailing dinghies such as Topper® Topaz Taz® or Laser® Pico®
Compact dimensions when folded for car transportation, comparable with windsurfing equipment (Weight 25 Kg, Length 3 m, “flat pack”)
Compatible with existing sailing rigs (e.g. windsurfing sails)
[0038] The boat is made out of a folded lightweight plastic sheet; e.g. sealed corrugated extruded sheets, since they provide rigidity and high buoyancy.
[0039] In the fold up configuration (sailing) it forms a hollow body, rigid enough to hold one passenger. In the closed position (transport) it is a ‘flat pack’ of folded panels, which store inside the other parts (rudder, centreboard and sail rig).
[0040] The development of the concept has been carried out by dividing the design work in packages and reiterating the following design steps:
Hull design (shape the boat in the water) Folding patterns (geometry studies to convert 2D in 3D) Deck design (design the space for the crew) Material and process Detail design (fixing, sealing solutions) Rig definition Prototyping
Hull Design
[0048] The idea of folding flat panels to obtain the three-dimensional hull shape suggests that the boat is going to have a polygonal surface, a “mesh” of flat or curved faces. Several methods for generating hull shapes have been considered:
[0000] Wrapping: using a flexible sheet and bending or wrap it in order to find a stable configuration (fixed in the minimum number of points). This method generates curved surfaces, but is quite hard to model on software, because of the important role played by the material elasticity. Thermoforming sheets has been used to sketch models.
Meshing: starting with a traditional curved hull surface, is it possible to mesh it on software packages to polygonal surfaces with small number of faces. The difficult of controlling the mesh generator on the tested software makes it difficult to obtain desired foldability and rigidity.
Geometrical assembly: as the opposite of meshing, it is possible to build polygonal surface from scratch by adding polygons to simple shapes. In this way it is possible to control the geometry and keeping the foldability of the hull. 3D software packages allow to generate quickly many shapes, which have been easily visualised with paper models.
[0049] With the last method a classification of possible polygonal surfaces, according to simple parameters as number of sides on the plan and on the main section. By increasing the number of sides the hull comes closer to the traditional curved hull, thus improving the performance but making the folding and structural issues more complex.
[0050] The hull shapes have to satisfy basic parameters to be considered for a boat. With the help of naval architecture texts and experts, I compiled a list of the primary criteria to analyze a sailing vessel:
[0000] Structural rigidity: especially longitudinal rigidity. The boat must not bend due to the effect of compression between water and crew weight.
Buoyancy: besides keeping afloat the crew without drafting too much, the boat needs to have reserve buoyancy for safety reasons. Positive flotation is the property of floating when filled with water (e.g. after capsize), and is normally achieved with extra floating bodies (e.g. foam) attached to the boat.
Stability: especially transversal stability is important for sail boats. The boat needs to generate a righting moment when heeled on the side. For small dinghies without a keel, this is anyway not enough to withstand the force of the wind on the sail and the position of the crew is crucial to keep the boat upright. Nevertheless stability is also comfort: not heeling hull design excessively when the crew moves from centre to side, is also much appreciated.
Drag: the resistance to the motion in the water is mainly given by the friction of the water on the boat, and it is proportional to the wetted surface. The second main component is generated by the motion of the waves.
Plane: the capacity of the boat to generate a vertical lift by the flow of the water under the hull depends on the hull geometry. If so the boat rises from water at speed (plane) and reduces the resistance to motion. This hydrodynamic effect is quite complicated to calculate also with software and is generally tested in water with models. Generally the flatter the hull, the more the lift it generates.
“Sailability”: or behaviour of the vessel in the sea in different conditions; e.g. sea-worthiness and sea-kindness.
[0051] The first four criteria can be predicted with calculations based on the hull geometry and have been analyzed for the generated hull shapes. A professional software (Rhinomarine, a 3D CAD/CAM program for modelling boats, their hydrostatics, stability and performance, produced by Proteus Engineering) has been used for the calculations. They do not exclude any of the shapes nor do they give us a clear winner. They confirm the intuition that increasing the number of sides, the performances increase as we have more parameters to adjust. The choice of the shape is then a trade-off between hull design and the other design areas, where these naval architecture criteria have also been considered.
[0052] The hydrostatic parameters for the proposed design have been also calculated and following these results, we can make following considerations.
[0053] Structural rigidity: The boat is designed for a displacement of 125 kg, i.e. the weight of a person (75 kg) plus the boat and eventual equipment. The pressure on the hull is therefore 125 kg over the wetted surface (about 2 m 2 ), which in different sailing conditions may reduce up to 50% (boat on a wave or on the plane): therefore 125 Kg/m 2 .
[0054] Buoyancy: The twin-walled plastic sheet is extremely buoyant and gives the boat an embedded safety reserve buoyancy, able to hold a person afloat in the case the boat should open up in water. The boat is made of about 10 m 2 of empty sheet: with an average thickness of 6 mm weight of 1 kg/m 2 , the material accounts for a positive flotation of 50 kg, enough to hold the equipment (mast) and support the person afloat. When folded up, the boat generates an enclosed volume of about 300 litres, which gives an displacement for 300 kg, useful for safe navigation on waves, when water may fill up the deck.
[0055] Stability: As can be seen in FIG. 1 , the boat has a positive righting moment (i.e. tends to return upright) up to a heel angle of around 80 degrees. The curve is calculated for an initial draft of 10 cm and a weight of 100 kg (in the middle of the boat).
Folding Patterns
[0056] Since the first paper models it has been clear that the folding plays an important role for the structural strength. A constant rule for the generation of folds, has been the utilization of triangular faces, in order to create only volumes composed by a number of tetrahedrons, to maximize the structural stability of the shape and to not rely only on the rigidity of the material. This approach guides the choice of the hull shape towards those with the least number of sides. The chosen shape is composed of two symmetrical tetrahedrons joint in the middle. More complicated shapes require dividing up the volume into more tetrahedrons and requiring more material, which then has to fold to a flat pack of minimal dimension.
[0057] In order to maximize the longitudinal rigidity no bends have been made on the longitudinal dimension. The boats folds up as a book with the spine on the length.
[0058] Important structural element of the boat is the transom. Different are the possibilities offered by the fold:
[0000] Double bottom: elegant and efficient solution that resist the folding in order to achieve necessary rigidity and sealing.
Solid transom (inserted panel): easy and structurally sound solution, adds an extra part to be carried and stored in the boat.
Solid transom (folded up): the sheet folds on the back as they fold on the front. This is the solution chosen for the proposed design.
Deck Design
[0059] After the water test of the test rig the deck has been redesigned. The crew on a sailing boat has to change position quite often and be able, especially on small dinghies, to sit anywhere in order to balance the boat. While a flat and slightly concave deck is actually quite appropriate for the latter purpose, it is quite uncomfortable for the legs, forcing the person to kneel rather than sit.
[0060] A raised border on the sides has been added to the final design in order to allow the passenger to sit on it. The border is an additional small tetrahedron with many functions. Besides forming a seat for the crew and something to hold on, it adds rigidity to the side. Most important function it joins the two sheets and forms the sealing.
[0061] Compared to the test rig configuration, the final design has two sheets of corrugated plastic, fixed in the middle to the central frame.
[0062] This configuration besides allowing the raised side border, allows also to use material of different thicknesses and to orient the corrugations of the two sheets in different directions, to increase the stability.
[0063] FIGS. 2 to 7 show the chosen folding pattern. FIG. 2 shows the boat ready for use. To pack the boat away the user must open the sides ( FIG. 3 ), open the back ( FIG. 4 ), insert the spars and close the internal sheet ( FIG. 5 ), close the external sheet ( FIG. 6 ) and pack the boat flat ( FIG. 6 ).
Material and Process
[0064] Materials suitable for this application are:
Multi-walled extruded polypropylene sheets, such as those used for signs, packaging or construction. For example, Correx® is a product produced by Kaysersberg® Plastics of Kaysersberg, France. Similarly Corriboard® is a product produced by Northern Ireland Plastics Ltd, Country Down, Northern Ireland. Corrugated polycarbonate sheets, which are available in a wider range of thicknesses and rigidity and often used for clear roofing. Plain polypropylene sheets Woven polypropylene sheets such as CURV®, which is produced by Propex Fabrics® GmbH Gronau, Germany Aluminium sheets joined with rubber or neoprene hinges
[0069] The choice of Correx® has been guided by the idea of realizing many functions in one part. The sheets act as the skin of the boat, have structural properties given by the rigidity of the corrugation, work as living hinges and when sealed on the edges they assure an extra buoyancy, very useful for a boat. With any other solution an additional material should have been introduced to realize those functions: i.e. a foam insert on the plain sheets to increase buoyancy.
[0070] Correx® is commercially available with a thickness range from 2 mm to 10 mm, with different grades. The test rig has been made out of 10 mm twin-walled polycarbonate sheet, proving to be rigid enough. The two sheets included in the proposed design can have different thicknesses, the internal one being lighter. Rigidity depends mostly on the thickness of the single layers or walls of the sheet profile. The right choice has to be made after building full scale prototypes with sheets in the 6 mm to 10 mm range.
[0071] The availability and the price on the market of this material is one of its advantages.
[0072] If the boat would be produced on a large scale, it might be possible to develop a custom extrusion. In that case the external layer should be thicker to increase the resistance to abrasion, the cells should have a triangular profile, which increases stability and makes scoring the folding lines easier.
[0073] Different solutions have been investigated to create the folding lines. The choice has fallen to profile rolling because it does not require bonding of material to polypropylene, which is possible only through welding (no adhesive are available for polypropylene) and therefore difficult for large surfaces. FIG. 8 illustrates the appearance of polypropylene after profile rolling.
[0074] To score the folding lines on the corrugated sheets, different tools and combinations of process parameters have been tested (i.e. temperature of material and tool, pressure and speed). The most successful process has been realized with a custom made tool that resembles an industrial pizza-cutter and prototypes a manual profile rolling. The material has been heated close to melting temperature and a cold tool has achieved better surface finishes.
[0075] Profile rolling allows furthermore to create curved hinges. These are quite important aesthetic features for the final design, as well as they allow the creation of curved surfaces.
Detail Design
[0076] The central frame has been introduced to add longitudinal rigidity to the boat and provide a structural element where all the equipment can be fixed: mast, centreboard, rudder, mainsheet and foot straps for the crew.
[0077] Materials that have been considered are: injection mould, pultrusion, aluminium extrusion, PVC extrusion, composite and fibreglass (GRP).
[0078] While the injection mould tends to be too expensive and technically difficult for this length, the pultrusion does not work well in torsion. The PVC extrusion has been used for the test rig and had to be reinforced to achieve sufficient rigidity. Aluminium extrusions can be realised in custom profiles, which would allow a better fixing of the Correx® sheets. It would be realised as the aluminium spars, which are the most common material for actual sailing masts.
[0079] The edges of the external Correx® sheet are welded at the bow and stern, in order to realize a closed surface in contact with the water. External and internal sheet are fixed to the central frame. The external edges of the two sheets fold on themselves realizing the seal to water, when rubber sealing strips are provided on the contact surfaces.
[0080] Several possibilities have been considered for the fixing of the fold: buttons, straps, bolts and Velcro® (hook and loop fastener). The last possibility has many benefits: lightweight, easy to open and close, invisible. Industrial types of Velcro® are available with high strength. Especially the moulded tapes, with symmetrical “mushrooms” sides. These plastic tapes can be glued or better welded to the polypropylene sheets. The symmetric tapes can used both for fixing the boat in the fold up configuration as well as flat pack.
[0081] An alternative to seal solution is an inflatable chamber inside the enclosed volume between the sheets. Such a chamber, realized in thin elastic material which folds on one of the sheets when closed, would solve completely the sealing problem, occupying the volume with air and giving extra rigidity to the structure. This solution has not been integrated so far to simplify the assembly process for the user and avoid pumping.
[0082] FIG. 9 shows the fixing and sealing solution for the external edges.
Rig Design
[0083] The design of a foldable sailing rig was included in the initial concept and different configurations have been considered. On the other side, masts in sections are quite collapsible and I decided to focus on the hull, which is the real volume to collapse, as the result of this project.
[0084] On the other hand, the idea of fitting commercially available rigs from other boats and especially from windsurfs has many benefits:
[0000] Wider range: windsurf sails are available in wide range of sizes to match the wind conditions. Similar concept could fit this lightweight boat.
Weight: windsurf rigs are lighter, because using fibre masts and that is essential for this lightweight boat.
Business model: attractive commercial strategy to enter the market with lower barrier: entry level customers do not need to buy a sail, but can reuse old ones. Windsurfers can have a low cost switch to sailing for a day or for the family. Custom sail could always be offered as optional.
[0085] FIGS. 10 to 15 show the hull in use with various sails: FIG. 10 is a windsurf like rig (boomless), for example a ‘batwing’ sail for a kayak; FIG. 11 is a rigid wing (more efficient, smaller size); FIG. 12 is a traditional mast/boom rig, for example a Topper; FIG. 13 is a Lateen sail (boomless) with front mast supports; FIG. 14 is a Lateen sail (boomless) with back mast supports; and FIG. 15 is a foldable rigid sail (in sections), same material as the hull.
Prototyping
[0086] During the whole process models and prototypes have been used:
[0000] Paper models
Polypropylene and Correx® scale models: to test the folds with thicker and harder material and to test in water.
RC model: the first sailing of the proposed hull shape has been realized with a radio controlled model with a polypropylene hull in scale 1:5.
Full-size cardboard model: The model has been used as test rig for the folding/unfolding process. The model showed how easy the folding could be and give an idea of the handling of boat in real size. Focusing on the fixing, this prototype inspired the idea of welding together the sheet edges at bow and stern; so that they are automatically in place during the opening/closing process. The idea of embedded handles for easy transportation came also from this test rig.
Full-size sailing test rig: It is made out of separate corrugated polycarbonate roofing sheets. The frame is obtained welding PVC square tubes and the hinges are realised with PVC tubes fixed to the sheets with fibreglass reinforced tape and hinged on an aluminium rod. The sailing rig and equipment is borrowed from a Topper dinghy and the weight of the mast has forced us to use a metal reinforcement on the PVC frame. The sealing has been obtained by taping the hinges, thus partially restricting the unfolding process. The total weight of the boat is 27 kg.
[0087] Features introduced during prototyping are: Improved deck design with raised borders; Velcro® fasteners; curved hinges; two corrugated sheets with corrugation in different direction for added rigidity.
Proposed Design
[0088] Dimensions:
fold up: 2.8 m×1.55 m×0.35 m flat pack: 2.98 m×0.90 m×0.10 m weight: 25 kg
[0092] Twin-wall extruded polypropylene sheet is used, cut and scored (profile rolling) to form the folding lines. Edge sealing and welding the material weights 15 kg and the required quantity (10 m 2 ) costs on the market about £60.
[0093] The frame is aluminium extrusion Machined to realise the fitting to the other parts. The supports (mast, centreboard, rudder) are injection moulded parts. The fasteners are industrial moulded “Velcro®” tape (welded on the polypropylene sheets) supports internal sheet frame sealing and fasteners external sheet
[0094] FIG. 16 shows the design, which is composed of an external sheet of multiwall extruded polypropylene 1 , an aluminium frame 2 , an internal sheet of multiwall extruded polypropylene 3 , a nylon injection moulded mast support 4 , nylon injection moulded centreboard supports 5 , 6 , a nylon injection moulded rudder support 7 and rubber and Velcro® sealing stripes 8 , 9 .
[0095] FIGS. 17 to 21 show a completed hull from various angles. FIG. 22 is another illustration of a completed hull. FIGS. 23 to 25 are three possible two-sheet configurations of the hull. | A floating vessel comprising, in the orientation of use, a central longitudinal member ( 2 ) having a vertical height, and to each side of the longitudinal member an upper substantially laminar panel ( 3 ) connected to the longitudinal member and extending outwardly therefrom and a lower substantially laminar panel ( 4 ) connected to the longitudinal member at a distance below the upper panel and extending outwardly from the longitudinal member, wherein the outermost edges of the upper and lower panels are connected and the lower panel is larger in the outward direction than the upper panel such that the panels form a stable structure. | 1 |
This is a continuation, of application Ser. No. 08/055,410, filed Apr. 29, 1993, now abandoned, which in turn is a continuation of application Ser. No. 07/765,337, filed Sep. 25, 1991, now abandoned.
The present invention relates to insect bait compositions useful for feeding stimuli to induce insects to preferably feed upon said bait composition. Therefore, when combined with an appropriate insecticide, the insect feeding upon the feeding stimuli containing compositions of the present invention will ingest the insecticide, which will then cause mortality of the insect.
More particularly, the present invention relates to insect bait compositions which are preferred feeding stimuli for cockroaches, wherein the bait stimuli will be consumed in high quantities by cockroaches under field conditions.
BACKGROUND OF THE INVENTION
Insects, especially cockroaches, are omnivorous insects. These insects typically infest locations that contain sufficient food, moisture and shelter for survival. Cockroaches forage for food randomly and will examine a food prior to ingesting it. If the food does not contain ingredients that stimulate feeding of the insect, the cockroach may continue to forage for appropriate food sources. An avoidance or lack of feeding on a bait containing poisonous material may reduce the effectiveness of the insecticide against cockroaches under field conditions. Therefore, the purpose of this invention is to formulate an insect bait, in particular a cockroach bait, that will be preferentially consumed in high quantities by cockroaches under both laboratory and field conditions.
Research has shown that German cockroaches, for example, cannot detect food from a large distance, that is, greater than five to ten inches. As a result, German cockroaches forage for food primarily along baseboards and behind appliances. As cockroaches encounter a bait station, the insect will examine the bait using this mouth parts and antennae. If the bait meets the cockroach nutritional needs, they may consume the bait. Cockroaches can learn to return to previously investigated food resources. Therefore, cockroach baits must be palatable enough to compete with other food sources in the environment to cause the insect to repeatedly visit the food resource and to ingest a lethal dose of toxicant applied thereto.
DISCUSSION OF THE PRIOR ART
U.S. Pat. No. 4,353,907 relates to amidino hydrazones useful in insect and fire ant bait formulations and compositions in mixture with fatty acids and an edible oil.
U.S. Pat. No. 4,845,103 relates to solid, non-particulate, non-flowable, non-repellant insecticide bait compositions for household control of cockroaches, comprising a pentadienone hydrazone insecticide compound, a food attractant system and a binder. The food attractant system is a mixture of liquid food selected from molasses, corn syrup, maple syrup, honey and mixtures of two of these foods, and a solid food-oatmeal.
U.S. Pat. No. 4,657,912 relates to a granular bait composition for control of ants, employing a pyrimidinone derivative in combination with ground pupae of silkworm.
U.S. Pat. No. 4,990,514 relates to insecticide bait compositions for control of cockroaches comprising an insecticide compound, a food attractant system and a flowable binder. The food attractant used in the composition comprises a mixture of liquid food selected from molasses, corn syrup, maple syrup, honey and mixtures of two or more of these food substances.
Japanese Patent Application 61:106505 discloses insect attracting compositions for ants containing as attractant components a mixture of carbohydrate, protein and lipid. Preferably, the carbohydrate is fruit juice, honey, sucrose, sugar, lactose, D-glucose, D-glucosamine, etc. Preferably, the composition is powdered, granular, solid, paste, liquid or gel. The protein source is an animal protein or vegetable protein, the lipid is a vegetable oil or animal oil. Various insect-controlling components are formulated with the attractant composition.
SUMMARY OF THE INVENTION
The purpose of this invention is to formulate a cockroach bait that will be consumed in high quantities by cockroaches under either field or laboratory conditions. German cockroaches forage for resources (food and water). It is the object of the present invention to disclose and provide a bait formulation which will stimulate prolonged insect feeding, particularly in cockroaches, also provided for is a bait that will be consumed. Further, the feeding bait stimulant composition should not require coverage of the total surface or area where target organisms forage for food and water. It is therefore the primary object of the present invention to disclose and provide a preferred feeding bait stimulant composition which will satisfy the cockroach nutritional needs and be consumed as a bait and at the same time palatable enough to compete with other food sources in the environment.
It is another object of the present invention to provide a feeding bait stimulant composition which will stimulate cockroach feeding for long periods of time and into which an active insecticide can be formulated to produce a lethal dose of toxicant in the cockroach.
Other objects of the present invention will be apparent from the following detailed description.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The foregoing objects of the present invention may be accomplished by forming a novel mixture or solution of proteinaceous food material and certain other ingredients, such as carbohydrates and various binding ingredients and carriers, to complete the composition.
The preferred embodiment of the present invention is a feeding stimulant composition consisting essentially of on a weight basis
from about 0% to about 50% proteinaceous food material as a feeding stimuli;
from about 0% to about 50% vegetable protein as a feeding stimuli/binder;
from about 0% to about 65% grain food as a feeding stimuli/binder;
from about 0% to about 30% carbohydrate as a feeding stimuli; and
from about 0% to about 40% lipid as a feeding stimuli/binder.
An antimicrobial and/or antioxidant agent also may be included. These feeding/bait compositions have been found to be exceedingly effective for consumption by insects, such as cockroaches (Blattella germanica, Periplaneta americana) which typically infest locations that contain sufficient food, moisture and shelter for survival.
A more preferred embodiment of this invention is a bait composition consisting essentially of on a weight basis:
from about 0% to about 50% spray-dried poultry liver;
from about 0% to about 50% ground silkworm pupae;
from about 0% to about 50% hydrogenated soy protein;
from about 15% to about 65% ground oatmeal;
from about 0% to about 30% high fructose corn syrup; and
from about 0% to about 40% partially hydrogenated soybean oil.
Examples of other carriers are fish meal, powdered sugar, flour, rice bran oil, corn oil, soybean oil, corn syrup, glucose, krill and the like. The compositions of the present invention are exceedingly effective for stimulating feeding in a variety of cockroach insects and subsequently when used with an insecticide controlling said cockroach population. Examples of other suitable carbohydrates include sucrose, maltose, arabi-nose, galactose, lactose, glucose, D-glucose, and D-glucosamine.
Silkworm pupae is a by-product of the silk industry obtained during the isolation of silk. Compositions of the invention may readily be prepared by grinding the dry pupae by conventional methods to maximize the yield of 10-60 mesh particles, which is preferred.
Spray drying methods are in the prior art and therefore no detailed exemplification need be given; however, in the interest of clarity, the following brief description of spray drying will be given. Spray drying is unique in that it dries a finely divided droplet by direct contact with the drying medium (usually air) in an extremely short retention time, 3 to about 30 seconds. This short contact time results in minimum heat degradation of the dried product. Drying from a particle generally takes place in two stages, the constant-rate and the falling rate period. The primary drying force is the temperature difference between the surrounding air and the temperature of the particle. This technique is particularly effective in preparing poultry liver useful in the present bait compositions.
Various other protein sources may be used in the present formulation. Animal digest is an acceptable source of animal protein coming from beef, poultry, fish and insect parts. Animal digest also includes internal organ parts obtained as by-products from slaughter house processing of such animals. These animal materials are preferably treated prior to user as by spray drying, freeze drying and oven drying.
In addition, this development may be formulated with a novel emulsion carrier for the active insecticidal ingredient, preferably a pentadien-3-one substituted amidino hydrazone insecticide as described in U.S. Pat. No. 4,087,525, for example,
1,5-bis (α,α,α-trifluoro-p-tolyl) -1,4-pentadien-3-one, 4,5,6,7-tetrahydro-1H-1,3-diazepine-2-yl hydrazone;
1,5- (bis (α,α,α-trifluoro-p-tolyl) -1,4-pentadien-3-one, 4,5,6,7-tetrahydro-1H-1,3 -diazepine-2yl hydrazone hydrochloride;
1,5-bis (p-chlorophenyl) -1,4 -pentadiene-3-one, 4,5,6,7-tetrahydro-1H-1,3-diazepine-2-yl hydrazone hydroiodide; and
1,5-bis (p-chorophenyl)-1,4-pentadiene-3-one, 4-phenyl- 2-imidazolin-2-yl hydrazone hydriodide. The disclosure of U.S. Pat. No. 4,087,525 is incorporated herein by reference thereto, describing the use of these compounds as insecticides.
Other insecticides can be substituted for the substituted amidino hydrazone insecticide, particularly organophosphates, such as:
chlorpyrifos--O,O-diethyl O-(3,5,6-trichloro-2 -pyridinyl) phosphorothioate;
carbamates, such as propoxur--2-(1-Methylethoxy) phenol methylcarbamate;
pyrethroids, such as phenothrin--(3-phenoxyphenyl)-methyl 2,2-dimethyl-3-(2-methyl-1-propenyl) cyclopropane carboxylate;
chlorinated hydrocarbons;
fluoroaliphatic sulfonamides, such as sulfluramid--N-ethyl perfluorooctane sulfonamide;
boric acid;
insect growth regulators, such as hydroprene--ethyl (E,E) -3,7,11-trimethyl-2, 4-dodecadienoate; and
microbially derived compounds, such as avermectin B 1 (a mixture of avermectins containing 80% avermectin B 1a (5-O-dimethylavermectin A 1 a(R=C 2 H 5 ) and 20% B 1 b (5-O-di-methyl-25-de(1-methylpropyl)-25- (1-methylethyl) avermectin A 1 a(R=CH 3 ).
The lipid phase contains soybean oil, a fatty acid, the active ingredient and an emulsifier and the aqueous phase contains a high fructose corn syrup. Other long chain fatty acids and various lipids would be acceptable substitutes or replacements for the fatty acid and lipid components identified herein.
Therefore, the present invention includes a method for controlling cockroaches comprising applying in the vicinity of their habitat or infested area an insecticidal bait composition consisting essentially of an insecticidally effective amount of a substituted amidino hydrazone insecticide or fatty acid salt thereof and the bait/feeding composition containing feeding bait stimulant composition according to the present invention. Additional edible carriers such as fish meal, sugars, flour and the like may be added and the mixture blended until homogeneous.
Optionally, from about 0.0% to about 2.0% of an anti-microbial agent such as sorbic acid/potassium sulfate, Dowcil™ 200 (cis isomer of 1-(3-chloroallyl)3,5,7-triaza-1-azonia-adamantane chloride), propyl paraben/methyl paraben (propyl p-hydroxybenzoate/methyl p-hydroxybenzoate) , Captan (N-(trichloromethylthio)-4-cyclohexane-1,2-dicarboximide) , sodium silicate, sodium dehydroacetate and sodium benzoate may be added to inhibit microorganism growth, or from about 0.0% to about 2.0% of an anti-oxidant such as tert-butyl hydroquinone, n-propyl gallate, 3-tert-butyl-4-hydroxyanisol and butylated hydroxy toluene or mixtures thereof may be incorporated during the blending of the composition to improve the storage characteristics of the final compositions, as can other agents such as thickening agents and the like.
The insecticidal composition with the bait according to the present invention can also be present in the form of an aerosol, in which case a co-solvent and a wetting agent are conveniently used, in addition to the propellant. The propellant is suitably a hydrochlorofluorocarbon alkane such as chloro difluoro methane, a non-halogenated alkane such as butane, and the like, carbon dioxide or nitrogen. The following types of formulations can be utilized to apply the formulated bait compositions with or without an effective amount of insecticidal agent: powders, dusts, granulates, solutions, suspensions, emulsions, emusifiable concentrates, pastes, foams, gels, fumigants, atomizing compositions, baits, and aerosols. The formulations of this invention can also be included in insect feeding stations such as bait trays.
The invention is further illustrated by the following non-limiting examples.
Procedure for Bait Compounding
Soybean oil (100 grams) (g), glycerylmonostearate (5 g), soy protein (58.5 g), and oleic acid (10 g) were mixed and heated to approximately 170° F. until all solids had dissolved. Corn syrup (50 g) heated to 140° F. was added to this and mixed to form an emulsion. Spray dried poultry liver (58.5 g), dried and ground silkworm pupae (58.5 g) and oatmeal (150 g) were added to the heated liquid and agitated until Uniform. The finished solution was poured into small cups and cooled to room temperature.
TABLE I______________________________________FORMULATIONS TESTED Silk- PartiallyEx. Poultry worm Soy Oat- Corn HydrogenatedNo. Liver Pupae Protein meal Syrup Soybean Oil______________________________________1 35.00 3.00 0.00 30.00 10.00 10.002 5.83 5.84 5.83 47.50 10.00 20.003 17.50 17.50 0.00 30.00 10.00 20.004 0.00 0.00 17.50 47.50 10.00 20.005 0.00 0.00 35.00 30.00 10.00 20.006 11.67 11.66 11.67 30.00 10.00 20.007 17.50 0.00 0.00 47.50 10.00 20.008 0.00 35.00 0.00 30.00 10.00 20.009 0.00 17.50 17.50 30.00 10.00 20.0010 17.50 0.00 17.50 30.00 10.00 20.0011 0.00 17.50 0.00 47.50 10.00 20.0012 0.00 0.00 0.00 65.00 10.00 20.0013 35.00 0.00 0.00 30.00 15.00 20.0014 0.00 25.00 0.00 30.00 0.00 40.0015 15.00 0.00 0.00 30.00 0.00 40.0016 12.50 17.50 0.00 30.00 15.00 20.0017 10.00 0.00 0.00 30.00 30.00 20.0018 35.00 0.00 0.00 30.00 30.00 0.0019 17.50 17.50 0.00 30.00 30.00 0.0020 0.00 35.00 0.00 30.00 10.00 20.0021 7.50 17.50 0.00 30.00 0.00 40.0022 35.00 0.00 0.00 30.00 0.00 30.0023 0.00 35.00 0.00 30.00 30.00 0.0024 10.00 0.00 0.00 30.00 15.00 40.00______________________________________
Active ingredient target is 2% by weight. Therefore, the compositions of the cited bait formulations sum to 98%, with the remainder available for the addition of active ingredient.
Explanation of Formulations Without Active Ingredient
For the above feeding bait stimulant composition tests, the experimental baits did not contain active ingredients, since the consumption of active ingredient would have inhibited further insect feeding. The test length was set to 3 days for each formula to collect sufficient feeding data. Presence of an active ingredient would have increased variability by causing mortality in the insect population feeding on the cockroach bait composition. Subsequent tests with the substituted amidino hydrazone active ingredient indicated that the insects fed upon the test baits containing active ingredient, notwithstanding the presence or absence of the active ingredient.
Explanation of Feeding Data
The feeding data were measured as weight loss of bait, relative to the mass of cockroaches in each container. The total mass of cockroaches used for each test could not be precisely controlled. A cockroach population of higher mass (more insects, higher proportion of adult insects) is expected to consume more bait than a smaller mass. In addition, consumption tests were run for three days. Therefore, the consumption of bait in each test was divided by three to report a standard, 1 day consumption figure.
The feeding data ratios were calculated as the ratio of feeding on the experimental bait to that of a standard bait base. The feeding data are presented in Table II.
TABLE II__________________________________________________________________________ Consumption Consumption Ratio of Feeding (mg Ratio of Feeding (mgEx. Lab Strain Field Strain Formula per mg of Formula per mg ofNo. (mg/g roach/day) (mg/g roach/day) Control) LAB STRAIN Control) FIELD STRAIN__________________________________________________________________________1.0 13.15 13.67 1.48 3.872.0 6.24 7.07 0.59 2.423.0 7.56 10.17 0.92 2.634.0 2.79 3.91 0.23 0.625.0 6.53 5.45 0.59 0.816.0 8.12 9.40 0.84 3.007.0 10.75 9.27 0.91 1.818.0 4.17 3.97 0.42 0.979.0 2.09 2.32 0.17 0.4110.0 9.44 11.06 0.88 1.7711.0 3.54 4.03 0.30 0.5712.0 0.11 5.50 0.01 0.8513.0 22.28 21.53 3.18 5.6914.0 9.68 16.91 0.52 5.2015.0 12.64 19.52 0.89 3.2216.0 21.07 24.40 2.43 5.9317.0 28.48 18.41 5.28 5.6018.0 33.41 20.50 5.22 3.9719.0 32.93 31.34 5.68 11.8020.0 17.24 20.21 1.22 8.3021.0 14.72 29.74 1.41 7.8022.0 16.52 21.91 1.29 5.2223.0 26.88 19.36 3.46 4.7724.0 26.55 26.73 3.59 6.85__________________________________________________________________________
The results of these experiments demonstrate the improved effectiveness as feeding stimuli of the compositions of this invention. Therefore, by utilizing the compositions of this invention, together with an insecticidally effective amount of insecticidal compound, the efficacy of the insecticidal compound can be increased where the mode of application of the insecticide depends upon the insect species feeding upon a source or bait containing the insecticide. | The insect bait composition in the present invention is useful for feeding stimuli to induce insects, especially cockroaches, to preferably feed upon said bait composition, which will stimulate insect feeding and successfully compete with other food sources in the environment, said stimulant bait composition having one or more protein sources derived from poultry liver, silkworm pupae and hydrogenated soy protein. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present invention claims priority from U.S. Provisional Patent Application No. 61/229,928 filed Jul. 30, 2009 which is incorporated herein by reference for all purposes.
TECHNICAL FIELD
The present invention relates to optical devices for routing and directing optical signals, and in particular to optical devices for rearranging wavelength-multiplexed optical signals in an optical communications network.
BACKGROUND OF THE INVENTION
The Internet services are currently provided using interconnected long-haul and metro optical networks. In modern long-haul and metro optical networks, optical signals are modulated with digital information and transmitted from one location to another, typically through a length of an optical fiber. To increase the information carrying capacity of the networks, modulated optical signals at different wavelengths, called “wavelength channels”, are grouped together (multiplexed) at one location of the network, transmitted through a common fiber to the other location of the network, and ungrouped (demultiplexed) at the other location.
As the Internet, Voice over Internet Protocol (VoIP) and streamed Internet Protocol (IP) television gain popularity, more and more subscribers desire to access these services from their premises. At present, these services are delivered to individual premises using either a twisted-pair Digital Subscriber Line (DSL) or a coaxial television cable. Due to the increased demand, the DSL and coaxial cable technologies are reaching their information carrying capacity limits, and optical technologies (so-called “Fiber To The Premises”, or FTTP) are increasingly used for delivering Internet services to individual premises.
Most FTTP technologies presently use a passive optical network (PON) architecture to provide fiberoptic access to the premises, because a PON architecture does not require expensive amplification and wavelength selective switching equipment commonly used in long-haul and metro optical networks. To deliver communication services from a central office to multiple individual subscribers, most PON systems use a passive star-type optical splitter and a form of time-division multiplexing (TDM) for delivering downstream and upstream information.
Disadvantageously, TDM-PON systems are quite complex and do not always provide a required degree of security of communications. A wavelength-division multiplexing (WDM) architecture can be attractive for a PON application, because in a WDM-PON, different wavelengths can be assigned to different subscribers or groups of subscribers, thus providing a higher degree of security of communications than a TDM-PON can provide. Furthermore, a WDM-PON architecture can potentially provide a broader bandwidth than a TDM-PON architecture. Nonetheless, WDM-PON systems so far have been relatively costly. For this reason, WDM-PON systems have not yet found a widespread utilization in cost-sensitive FTTH applications.
WDM-PON systems utilize wavelength-selective combiners and splitters of optical signals called “WDM multiplexors” and “WDM demultiplexors”, respectively. To save costs, a WDM multiplexor and a WDM demultiplexor of a WDM-PON system can be combined into a single unit, which is referred to as a “de/multiplexor”. Referring to FIG. 1A , a prior-art arrayed waveguide (AWG) WDM de/multiplexor 100 is shown having a single input port 102 and four output ports 111 to 114 . Four wavelength channels λ 1 C , λ 2 C , λ 3 C , λ 4 C of central (“C”) band of optical communications and four wavelength channels λ 1 S , λ 2 S , λ 3 S , λ 4 S of short (“S”) band optical communications are present at the input port 102 . The WDM de/multiplexor 100 directs wavelengths λ 1 C , λ 1 S to the output port 111 ; wavelengths λ 2 C , λ 2 S to the output port 112 ; wavelengths λ 3 C , λ 3 S to the output port 113 ; and wavelengths λ 4 C , λ 4 S to the output port 114 . To direct different wavelengths to a same output port, the WDM de/multiplexor 100 uses a diffractive optical device having multiple orders of diffraction. The WDM de/multiplexor 100 is bidirectional, that is, the wavelength channels arriving at the output ports 111 - 114 can be combined into a single multi-channel signal at the input port 102 . Referring now to FIG. 1B , a WDM-PON 120 has two nodes 121 and 122 coupled through a length of an optical fiber 123 . Each node 121 and 122 has one WDM de/multiplexor 100 . The input ports 102 of the WDM de/multiplexors 100 of the nodes 121 and 122 are connected together by the optical fiber 123 . The output ports 111 to 114 of the WDM de/multiplexors 100 are coupled to duplex optical filters 124 coupled to corresponding transmitters 126 and receivers 128 . The node 121 uses the wavelength channels λ 1 C , λ 2 C , λ 3 C , λ 4 C for transmission and the wavelength channels λ 1 S , λ 2 S , λ 3 S , λ 4 S for reception. The node 122 uses the wavelength channels λ 1 S , λ 2 S , λ 3 S , λ 4 S for transmission and the wavelength channels λ 1 C , λ 2 C , λ 3 C , λ 4 C for reception. The direction of flow of the signals is shown with arrows 127 . Thus, each WDM de/multiplexor 100 is used for both multiplexing and demultiplexing wavelength channels, whereby significant cost savings can be achieved.
Disadvantageously, in the AWG WDM de/multiplexor 100 , and in any diffraction grating based demultiplexor for that matter, the wavelengths of the channels λ i S and λ i C directed to a same i th output port in different orders of diffraction m and m+1 are tied together by the grating equation: λ i S ≈λ i C m/(m+1) and therefore cannot be selected independently from each other. As a result, the WDM-PON 120 does not allow a system designer to select the wavelength channels λ 1 C , λ 2 C , λ 3 C , λ 4 C independently from the wavelength channels λ 1 S , λ 2 S , λ 3 S , λ 4 S . This represents a considerable limitation, especially for a FTTP application where the available bandwidth needs to be utilized to a full extent to provide as broad coverage as possible at a given cost.
It is therefore an object of the invention to provide an optical device for directing and regrouping wavelength channels, wherein the wavelengths of the channels directed to the same output port are independently selectable. The independent wavelength selection improves bandwidth utilization and network efficiency. As a result, a deployment cost to provide a FTTH-based broadband Internet service to individual subscribers is reduced.
SUMMARY OF THE INVENTION
An optical device of the invention achieves independent routing of two or more wavelength channels to a same output port of an optical grating multiplexor by providing two or more separate input ports for the optical grating demultiplexor. The input ports are offset from each other so as to provide a required wavelength separation between the two or more wavelength channels intended for coupling to a same output port. The wavelength channels are initially separated into two or more groups of channels, one group per one input port of the optical grating multiplexor. The groups of wavelength channels are then separately coupled to the input ports of the optical grating multiplexor.
In accordance with the invention there is provided an optical device for rearranging wavelength channels, comprising:
a wavelength selective coupler having an input port and first and second output ports, for separating wavelength channels received at the input port into first and second groups of wavelength channels for output at the first and the second output ports, respectively;
an optical grating demultiplexor having first and second input ports optically coupled to the first and the second output ports of the wavelength selective coupler, respectively, and a plurality of output ports, for demultiplexing the first and the second groups of wavelength channels;
wherein the first and the second input ports of the optical grating demultiplexor are offset from each other so as to couple a wavelength channel of the first group from the first input port, together with a wavelength channel of the second group from the second input port, into a same output port of the optical grating demultiplexor.
In one embodiment, the wavelength selective coupler includes an optical interleaver having one input and two outputs coupled to the first and the second input ports of the optical grating demultiplexor. Advantageously, this allows one to use the optical grating demultiplexor having channel spacing twice as big as the channel spacing of the wavelength channels. By way of example, this embodiment of the invention allows a 100 GHz demultiplexor to be used in an optical network having 50 GHz spaced channels.
In one embodiment, the optical device of the invention further includes a plurality of wavelength selective splitters. Each wavelength selective splitter is optically coupled to one of the plurality of the output ports of the optical grating demultiplexor, functioning as a separator of wavelength channels of the first group from wavelength channels of the second group. The wavelength selective splitters are preferably duplex filters for bidirectional communication, wherein the first group of channels carries information in one direction, and the second group of channel carries information in the other, opposite direction.
In accordance with another aspect of the invention there is further provided an optical network node comprising:
the optical device for rearranging the wavelength channels;
a plurality of receivers each coupled to a particular one of the duplex filters for receiving a transmission channel; and
a plurality of transmitters each coupled to a particular one of the duplex filters for transmitting a transmission channel.
In accordance with yet another aspect of the invention there is further provided an optical network comprising two optical network nodes and an optical transmission line that couples together the input ports of the wavelength selective couplers of the two optical network nodes,
wherein the transmission channels of the first optical network node are the reception channels of the second optical network node, and vice versa.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments will now be described in conjunction with the drawings in which:
FIG. 1A is a block diagram of a prior-art arrayed waveguide demultiplexor;
FIG. 1B is a block diagram of a WDM passive optical network having two demultiplexors of FIG. 1A ;
FIG. 2A is a block diagram of an optical device of the invention having a wavelength division multiplexor coupled to an optical grating demultiplexor;
FIG. 2B is a block diagram of an optical device of the invention having an optical interleaver coupled to an optical grating demultiplexor;
FIG. 2C is a block diagram of a variant of the optical device of FIG. 2B having a different offset between the input ports of the optical grating demultiplexor;
FIG. 3 is a spectrum of wavelength channels coupled to the input ports of the optical devices of FIGS. 2B and 2C ;
FIG. 4 is a block diagram of an optical device of the invention having 1:N wavelength selective coupler and N:M optical grating demultiplexor;
FIG. 5 is a plan view of an optical device of FIGS. 2A to 2C , having an arrayed waveguide grating; and
FIG. 6 is a block diagram of an optical network of the invention.
DETAILED DESCRIPTION OF THE INVENTION
While the present teachings are described in conjunction with various embodiments and examples, it is not intended that the present teachings be limited to such embodiments. On the contrary, the present teachings encompass various alternatives, modifications and equivalents, as will be appreciated by those of skill in the art.
Referring to FIG. 2A , an optical device 200 A of the invention includes a wavelength division multiplexor 202 A coupled to an optical grating demultiplexor 210 . The wavelength division multiplexor 202 A has an input port 204 and first and second output ports 206 and 208 , respectively. The function of the wavelength division multiplexor 202 A is to separate wavelength channels λ 1 to λ 8 received at the input port 204 into first and second groups of wavelength channels λ 1 to λ 4 and λ 5 to λ 8 , respectively, and direct them to the first and the second output ports 206 and 208 , respectively.
The first and the second output ports 206 and 208 are coupled to first and second input ports 212 and 214 , respectively, of the optical grating demultiplexor 210 . The function of the optical grating demultiplexor 210 is to demultiplex the first and the second groups of wavelength channels λ 1 to λ 8 and to direct the demultiplexed channels towards a plurality of output ports 216 to 219 of the optical grating demultiplexor 210 . The first and the second input ports 212 and 214 of the optical grating demultiplexor 210 are offset from each other so as to couple a wavelength channel of the first group λ 1 to λ 4 from the first input port 212 , together with a wavelength channel of the second group λ 5 to λ 8 from the second input port 214 , into a same output port 216 , 217 , 218 , or 219 , of the optical grating demultiplexor 210 . Thus, the output port 216 has the wavelength channels λ 1 and λ 5 ; the output port 217 has the wavelength channels λ 2 and λ 6 ; the output port 218 has the wavelength channels λ 3 and λ 7 ; and the output port 219 has the wavelength channels λ 4 and λ 8 . Advantageously, the presence of two offset input ports 212 and 214 allows the wavelengths λ 1 and λ 5 to be individually selectable by adjusting the magnitude of the offset between the input ports 212 and 214 . The wavelength adjustability will be illustrated further below.
Turning now to FIG. 2B , an optical device 200 B is an alternative embodiment of the optical device 200 A. One difference between the optical devices 200 A and 200 B is that the optical device 200 B includes an optical interleaver 202 B instead of the WDM filter 202 A. The function of the optical interleaver 202 B is to separate wavelength channels λ 1 to λ 8 received at the input port 204 into first and second groups of wavelength channels λ 1 , λ 3 , λ 5 , λ 7 and λ 2 , λ 4 , λ 6 , λ 8 , respectively, and direct them to the first and the second output ports 206 and 208 , respectively. The optical interleaver preferably has an input channel spacing twice as small as a channel spacing of the optical grating demultiplexor 310 . Advantageously, the optical grating demultiplexor 210 can have a larger channel spacing than the channel spacing of an optical network wherein the optical device 200 B is used. For example, the optical grating demultiplexor 210 can have a 100 GHz channel spacing, while the optical network it is used in can have a 50 GHz channel spacing.
As noted above, one important advantage of the invention is the adjustability of wavelengths of the channels that are coupled together in the same output port 216 , 217 , 218 , or 219 of the optical grating demultiplexor. Turning to FIG. 2C , an optical device 200 C is shown. The optical device 200 C is a variant of the optical device 200 B. One difference between the optical devices 200 B and 200 C is that an optical grating demultiplexor 211 of the optical device 200 C has an input 220 that is offset by an additional amount of as compared to a position of the corresponding input 214 of the optical grating demultiplexor 210 of the optical device 200 B of FIG. 2B . The additional offset is illustrated at 225 in FIG. 2C . The additional offset determines which ones of the wavelength channels λ 2 , λ 4 , λ 6 , λ 8 are coupled to which ones of the output ports 216 to 219 of the optical grating demultiplexor 211 .
Referring now to FIG. 3 , a spectrum 311 shows the wavelength channels λ 1 to λ 8 at the input port 204 of the optical devices 200 B and 200 C of FIGS. 2B and 2C . In FIG. 3 , a spectrum 312 shows the wavelength channels λ 1 , λ 3 , λ 5 , λ 7 at the upper input port 212 of the optical grating demultiplexors 210 and 211 .
A spectrum 313 shows even wavelength channels λ 2 , λ 4 , λ 6 , λ 8 at the lower input port 214 of the optical grating demultiplexor 210 of FIG. 2B . In FIG. 3 , the spectrum 313 is shifted so that the even wavelength channels λ 2 , λ 4 , λ 6 , λ 8 line up with the odd wavelength channels λ 1 , λ 3 , λ 5 , λ 7 , due to the offset between the input ports 212 and 214 of the optical grating demultiplexor 210 of FIG. 2B . As a result of the offset, the pairs of wavelength channels λ 1 and λ 2 ; λ 3 and λ 4 ; λ 5 and λ 6 ; λ 7 and λ 8 are coupled into the output ports 216 to 219 , respectively. The output ports 216 to 219 are shown in FIG. 3 lined up with the corresponding wavelength channel pairs λ 1 and λ 2 ; λ 3 and λ 4 ; λ 5 and λ 6 ; λ 7 and λ 8 .
A spectrum 314 shows the even wavelength channels λ 2 , λ 4 , λ 6 , λ 8 at the lower input port 220 of the optical grating demultiplexor 211 of FIG. 2C . In FIG. 3 , the spectrum 314 is shifted as shown at 325 so that the wavelength channels λ 4 , λ 6 , λ 8 line up with the wavelength channels λ 1 , λ 3 , λ 5 due to the additional offset shown at 225 . As a result of the additional offset , the pairs of wavelength channels λ 1 and λ 4 ; λ 3 and λ 6 ; λ 5 and λ 8 are coupled into the output ports 216 to 218 , respectively. The output ports 216 to 218 are shown in FIG. 3 lined up with the corresponding wavelength channel pairs λ 1 and λ 4 ; λ 3 and λ 6 ; λ 5 and λ 8 . The remaining wavelength channels λ 2 and λ 7 are coupled into an additional output port 315 and the output port 219 , respectively. The additional output port 315 is not shown in FIG. 2C .
By properly selecting the additional offset , one can increase the wavelength separation of the wavelength channels coupled together into a same output port of the optical grating demultiplexor 211 . In FIG. 3 , for example, wavelength channel pairs λ 1 and λ 4 at the output port 216 are separated three times more than the input channels λ 1 and λ 2 . Advantageously, selecting wavelength channels that are separated by at least three times more than the input channel spacing to be directed to a same output port, simplifies subsequent demultiplexing of these channels, because of the increased wavelength separation of these wavelength channels. At the same time, the advantage brought in by the interleaver 202 B, specifically a wider channel spacing of the optical grating demultiplexor 211 , is kept. In other words, the optical grating demultiplexor 211 can have a channel spacing that is twice bigger than the channel spacing at the input of the optical device 200 C.
Referring now to FIG. 4 , a more general form of an optical device of the invention is presented. An optical device 400 of the invention has a 1:M wavelength selective coupler 402 having one input port 404 and M output ports 406 - 1 . . . 406 -M, wherein M≧3. The 1:M wavelength selective coupler 402 is coupled to an M:N optical grating demultiplexor 410 having M input ports 412 - 1 . . . 412 -M and N output ports 416 - 1 . . . 416 -N, wherein N≧3. The M output ports 406 - 1 . . . 406 -M of the 1:M wavelength selective coupler 402 are coupled to the M input ports 412 - 1 . . . 412 -M of the M:N optical grating demultiplexor 410 , respectively. The function of the 1:M wavelength selective coupler 402 is to separate wavelength channels λ 1 1 . . . λ N 1 , λ 1 2 . . . λ N 2 , . . . , and λ 1 M . . . λ N M into M groups of wavelength channels λ 1 1 . . . λ N 1 ; λ 1 2 . . . λ N 2 ; . . . ; and λ 1 M . . . λ N M , each group being directed to a corresponding output port 406 - 1 ; 406 - 2 ; . . . ; 406 -M. The function of the optical grating demultiplexor 410 is to demultiplex wavelength channels of each of the M groups received at M input ports 412 - 1 . . . 412 -M and to direct the demultiplexed channels λ 1 1 . . . λ 1 M ; λ 2 1 . . . λ 2 M ; . . . ; and λ N 1 . . . λ N M towards the output ports 416 - 1 . . . 416 -N, respectively. By properly selecting the positions of the input ports 412 - 1 . . . 412 -M of the M:N optical grating demultiplexor 410 , one can select which wavelength channels are directed to which one of the output ports 416 - 1 . . . 416 -N. The positions of the input ports are selected based on a grating equation of an optical grating used in the M:N optical grating demultiplexor 410 . The grating equations of some commonly used optical gratings are given further below.
The WDM coupler 202 A or 402 can use any type of a wavelength selective filter such a dichroic (thin film) optical filter, for example. The WDM couplers 202 A and 402 and the interleaver 202 B can be replaced with any other type of a wavelength selective coupler for separating wavelength channels received at the input port 204 into at least two groups of (not necessarily adjacent) wavelength channels. The optical interleaver 202 B preferably includes at least one Mach-Zehnder (MZ) interferometer. Two serially coupled MZ interferometers forming a lattice filter are further preferable. The optical grating demultiplexors 210 , 211 , and 410 can include an arrayed waveguide grating (AWG), a bulk Echelle grating, a slab Echelle grating, or a bulk diffraction grating.
Referring to FIG. 5 , an optical device 500 of the invention includes serially coupled a 1×2 wavelength selective coupler 502 and an AWG demultiplexor 510 having an input slab section 521 , a waveguide section 522 coupled to the input slab section 521 , an output slab section 523 coupled to the waveguide section 522 , two input waveguides 512 and 514 coupled to the input slab section 521 , and a plurality of output waveguides 516 to 519 coupled to the output slab sections 523 . The AWG demultiplexor 510 is preferably based on an athermal AWG using any athermal AWG types known to a person skilled in the art. The wavelength selective coupler 502 is preferably waveguide based, so it can be integrated on the same waveguide substrate as the AWG demultiplexor 510 .
The principle of adjustability of which wavelength channel is directed to which output port (depending on the input port position) will now be explained. The relative position of the input ports 212 and 214 of the optical grating demultiplexor 210 ; the relative position of the input ports 212 and 220 of the optical grating demultiplexor 211 ; the relative position of the input ports 412 - 1 . . . 412 -M of the M:N optical grating demultiplexor 410 ; and the relative position of the input ports 512 and 514 of the arrayed waveguide grating demultiplexor 510 is defined by a grating equation of a particular optical grating used in these devices. The grating equations of various optical gratings are known to one of ordinary skill in the art. The grating equation of an arrayed waveguide grating, for example, is
n s (λ) p sin(θ in )+ n s (λ) p sin(θout)+ n w (λ)Δ L=mλ (1),
wherein n s (λ) is a refractive index of the slab sections 521 and 523 , n w (λ) is a refractive index of the waveguide section 522 , θ in is an input beam angle of an optical beam emitted by the input waveguide 512 or the input waveguide 514 , θ out is an output beam angle of an optical beam coupled into the output waveguides 516 to 519 , ΔL is an optical path difference between neighboring waveguides of the waveguide section 522 , p is a waveguide spacing of the waveguide section 522 , and m is an order of diffraction. According to the grating equation (1), by selecting proper angles θ in , which depends on a position of an input waveguide, different wavelength channels can be coupled into a same output waveguide in a different orders of diffraction m or even in a same order of diffraction m.
The grating equation of a free-space diffraction grating is similar to Equation (1) above:
nd (sin θ in +sin θ out )= mλ (2),
wherein n is refractive index of a medium the diffraction grating is in, and d is a groove spacing of the diffraction grating. By properly selecting the input beam angles θ in , one can couple different wavelength channels into a same output port. The input beam angles θ in and the output beam angles θ out depend on position of the input and output ports of the free-space diffraction grating and on a focal length of a lens or lenses used to collimate the input and the output beams. These free space lenses correspond to the input and the output slabs 521 and 523 of the arrayed waveguide grating demultiplexor 510 of FIG. 5 .
In the optical grating demultiplexors 210 , 211 , and 410 , the input ports 212 , 214 , 220 , and 412 - 1 to 412 -M can be disposed so that different wavelength channels can be directed to a same output port by diffracting into different orders of diffraction. This provides for a freedom to space the input ports apart by enough of a distance to prevent crosstalk, for example. Furthermore, according to the present invention and the Equations (1) and (2) above, the input ports 212 , 214 , 220 , and 412 - 1 to 412 -M can also be disposed so that different wavelength channels are directed to a same output port by diffracting into a same order of diffraction m. This provides an important design benefit because the optical grating demultiplexors 210 , 211 , and 410 do not need to be optimized for operation in different orders of diffraction, which allows one to achieve a better optical performance in a single order of diffraction m.
Turning now to FIG. 6 , an optical network 600 of the invention includes nodes 602 and 604 coupled by a length of an optical fiber 606 . Each of the nodes includes the optical device 200 A of the invention, a plurality of duplex filters 612 coupled to the output ports 216 to 219 of the optical grating demultiplexors 210 , for separating wavelength channels present at the output ports 216 to 219 , a plurality of receivers 620 each coupled to a particular one of the duplex filters 612 , and a plurality of transmitters 630 each coupled to a particular one of the duplex filters 612 . As seen in FIG. 6 , the wavelength channels λ 5 to λ 8 are transmission wavelength channels for the node 602 and are accordingly reception wavelength channels for the node 604 . The wavelength channels λ 1 to λ 4 are reception wavelength channels for the node 602 and are transmission wavelength channels for the node 604 . Of course, the wavelength selective coupler 502 , the interleaver 202 B, or the 1×M wavelength selective splitter 402 can be used in place of the wavelength division multiplexor 202 A, and the AWG demultiplexor 510 , the optical grating demultiplexor 211 , or the M×N optical grating demultiplexor 410 can be used in place of the optical grating demultiplexor 210 . The transmitters 630 are preferably laser diodes, although light emitting diodes (LEDs) can also be used. The receivers 620 are preferably PIN or avalanche photodiodes. | An optical device for rearranging wavelength channels in an optical network is disclosed. The optical device has a wavelength selective coupler having one input port and a plurality of output ports coupled to a plurality of input ports of an optical grating demultiplexor such as an arrayed waveguide grating. The wavelength channels in each of the input ports are dispersed by the demultiplexor and are directed to a plurality of output ports of the optical grating demultiplexor. As a result, at least one wavelength channel at each of the input ports of the optical grating demultiplexor is coupled into a common output port. The optical device is useful in passive optical networks wherein a same demultiplexor is used for simultaneous multiplexing and demultiplexing of wavelength channels. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
None.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
BACKGROUND OF THE INVENTION
The invention relates to a method for improving the Bayer process for the production of alumina from bauxite ore. The invention concerns the use of scleroglucan to improve the performance of unit operations within the Bayer process, specifically to enhance the settling of fine alumina trihydrate crystals.
In the typical Bayer process for the production of alumina trihydrate, bauxite ore is pulverized, slurried with caustic solution, and then digested at elevated temperatures and pressures. The caustic solution dissolves oxides of aluminum, forming an aqueous sodium aluminate solution. The caustic-insoluble constituents of bauxite ore are then separated from the aqueous phase containing the dissolved sodium aluminate. Solid alumina trihydrate product is precipitated out of the solution and collected as product.
As described at least in part, among other places, in U.S. Pat. No. 6,814,873, the Bayer process is constantly evolving and the specific techniques employed in industry for the various steps of the process not only vary from plant to plant, but also are often held as trade secrets. As a more detailed, but not comprehensive, example of a Bayer process, the pulverized bauxite ore may be fed to a slurry mixer where aqueous slurry is prepared. The slurry makeup solution is typically spent liquor (described below) and added caustic solution. This bauxite ore slurry is then passed through a digester or a series of digesters where the available alumina is released from the ore as caustic-soluble sodium aluminate. The digested slurry is then cooled, for instance to about 220° F., employing a series of flash tanks wherein heat and condensate are recovered. The aluminate liquor leaving the flashing operation contains insoluble solids, which solids consist of the insoluble residue that remains after, or are precipitated during, digestion. The coarser solid particles may be removed from the aluminate liquor with a “sand trap”, cyclone or other means. The finer solid particles may be separated from the liquor first by settling and then by filtration, if necessary.
The clarified sodium aluminate liquor is then further cooled and seeded with alumina trihydrate crystals to induce precipitation of alumina in the form of alumina trihydrate, Al(OH) 3 . The alumina trihydrate particles or crystals are then classified into various size fractions and separated from the caustic liquor. The remaining liquid phase, the spent liquor, is returned to the initial digestion step and employed as a digestant after reconstitution with caustic.
Within the overall process one of the key steps is that of precipitation of the alumina trihydrate from the clarified sodium aluminate liquor. After the insoluble solids are removed to give the clarified sodium aluminate liquor, also referred to as “green liquor”, it is generally charged to a suitable precipitation tank, or series of precipitation tanks, and seeded with recirculated fine alumina trihydrate crystals. In the precipitation tank(s) it is cooled under agitation to induce the precipitation of alumina from solution as alumina trihydrate. The fine particle alumina trihydrate acts as seed crystals which provide nucleation sites and agglomerate together and grow as part of this precipitation process.
Alumina trihydrate crystal formation (the nucleation, agglomeration and growth of alumina trihydrate crystals), and the precipitation and collection thereof, are critical steps in the economic recovery of aluminum values by the Bayer process. Bayer process operators strive to optimize their crystal formation and precipitation methods so as to produce the greatest possible product yield from the Bayer process while producing crystals of a given particle size distribution. A relatively large particle size is beneficial to subsequent processing steps required to recover aluminum metal. Undersized alumina trihydrate crystals, or fines, generally are not used in the production of aluminum metal, but instead are recycled for use as fine particle alumina trihydrate crystal seed. As a consequence, the particle size of the precipitated trihydrate crystals determines whether the material is to be ultimately utilized as product (larger crystals) of as seed (smaller crystals). The classification and capture of the different sized trihydrate particles is therefore an important step in the Bayer process.
This separation or recovery of alumina trihydrate crystals as product in the Bayer process, or for use as precipitation seed, is generally achieved by settling, cyclones, filtration and/or a combination of these techniques. Coarse particles settle easily, but fine particles settle slowly. Typically, plants will use two or three steps of settling in order to classify the trihydrate particles into different size distributions corresponding to product and seed. In particular, in the final step of classification a settling vessel is often used to capture and settle the fine seed particles. Within the settling steps of the classification system, flocculants can be used to enhance particle capture and settling rate.
The overflow of the last classification stage is returned to the process as spent liquor. This spent liquor will go through heat exchangers and evaporation and eventually be used back in digestion. As a result, any trihydrate particles reporting to the overflow in this final settling stage will not be utilized within the process for either seed or product. Effectively such material is recirculated within the process, creating inefficiencies. Therefore, it is important to achieve the lowest possible concentration of solids in the overflow of the last stage of classification to maximize the efficiency of the process.
As described for example in U.S. Pat. No. 5,041,269, conventional technology employs the addition of synthetic water soluble polyacrylate flocculants and/or dextran flocculants to improve the settling characteristics of the alumina trihydrate particles in the classification process and reduce the amount of solids in the spent liquor. While various flocculants are often used in the trihydrate classification systems of Bayer plants, it is highly desirable to reduce as far as possible, the loss of solids with the spent liquor.
Thus there is clear need and utility for a method of improving the classification and flocculation of precipitated alumina trihydrate in the Bayer process. Such improvements would enhance the efficiency of the production of alumina from bauxite ore.
The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 CFR §1.56(a) exists.
BRIEF SUMMARY OF THE INVENTION
At least one embodiment of the invention is directed towards a method for settling alumina trihydrate in the Bayer process. The process comprises adding to the system an effective amount of scleroglucan. The use of such a scleroglucan results in improved settling of alumina trihydrate when compared to the use of conventional flocculants employed in this process.
At least one embodiment of the invention is directed towards a method for producing alumina comprising the addition of a composition containing one or more polysaccharides, one of which is scleroglucan to liquor of a Bayer process fluid stream. The composition may be added to said liquor in a trihydrate classification circuit of said alumina production process. The composition may be added to said liquor at one or more locations in said process where solid-liquid separation occurs. The addition locations may facilitate inhibiting the rate of nucleation of one or more alumina trihydrate crystals in said process. The addition location may facilitate reducing the rate of scale formation in said process. The composition may improve the yield of alumina trihydrate sequestration. At least one embodiment of the invention is directed towards a composition comprising scleroglucan and Bayer liquor.
DETAILED DESCRIPTION OF THE INVENTION
For purposes of this application the definition of these terms is as follows:
“Scleroglucan” is a polysaccharide consisting of beta-1,3-D-glucose residues with one beta-1,6-D-glucose side chain every three main residues
“Liquor” or “Bayer liquor” is liquid medium that has run through a Bayer process in an industrial facility.
In the event that the above definitions or a description stated elsewhere in this application is inconsistent with a meaning (explicit or implicit) which is commonly used, in a dictionary, or stated in a source incorporated by reference into this application, the application and the claim terms in particular are understood to be construed according to the definition or description in this application, and not according to the common definition, dictionary definition, or the definition that was incorporated by reference. In light of the above, in the event that a term can only be understood if it is construed by a dictionary, if the term is defined by the Kirk - Othmer Encyclopedia of Chemical Technology, 5th Edition, (2005), (Published by Wiley, John & Sons, Inc.) this definition shall control how the term is to be defined in the claims.
In at least one embodiment, a process for extracting alumina trihydrate comprises the digestion of pretreated bauxite ore in an alkaline liquor to produce a slurry of red mud solids and aluminate in suspension in the alkaline liquor then decanting the red mud solids from the alkaline liquor suspension to produce the decanting liquor; the passing of said decanting liquor through security filtration to remove all solids, precipitation and production of a slurry containing alumina trihydrate solids which then are flocculated and settled with the addition of a polysaccharide. Larger trihydrate particles are put through the calcination process to produce purified alumina while finer particles are re-used as seed for the precipitation process.
In at least one embodiment the preferred flocculant of the trihydrate solids in the process is scleroglucan or a blend of scleroglucan with one or more other polysaccharides such as dextran. The flocculant is added in the range of 0.1 to 100 ppm. The most preferred dose range for the flocculant is 0.1 to 10 ppm.
As described at least in U.S. Pat. Nos. 6,726,845, 3,085,853, 5,008,089, 5,041,269, 5,091,159, 5,106,599, 5,346,628 and 5,716,530 and Australian Patents 5,310,690 and 737,191, polysaccharides such as dextran have previously been used in the Bayer Process. However, use of scleroglucan results in superior and unexpected improvements in the activity when compared to conventional polysaccharides or other reagents.
In at least one embodiment the composition is added to liquor in a trihydrate classification circuit of said alumina trihydrate production process. The composition can be added to said liquor at one or more locations in a Bayer process where solid-liquid separation occurs.
In at least one embodiment the composition can be added to said liquor at one or more locations in a Bayer process where it inhibits the rate of nucleation of one or more alumina hydrate crystals in said process.
In at least one embodiment the composition can be added to said liquor at one or more locations in a Bayer process where it reduces the rate of scale formation in said process.
In at least one embodiment the composition can be added to said liquor at one or more locations in a Bayer process where it facilitates red mud clarification in the process.
In at least one embodiment the composition can be added in combination with or according to any of the compositions and methods disclosed in commonly owned and at least partially co-invented co-pending patent application Ser. No. 12/852,910 and a title of “THE RECOVERY OF ALUMINA TRIHYDRATE DURING THE BAYER PROCESS USING CROSS-LINKED POLYSACCHARIDES.”
EXAMPLES
The foregoing may be better understood by reference to the following examples, which are presented for purposes of illustration and are not intended to limit the scope of the invention.
Within the examples given below a range of solutions containing scleroglucan and dextran in various ratios were used. The performance of these blends was compared to the performance of scleroglucan and/or dextran when used alone. The compositions of the combined formulations tested are given in table 1 . When doses of such blends are quoted, this refers to the combined amount of scleroglucan plus dextran added to the process.
TABLE 1
Ratio of components in blended formulations
used within the examples
Ratio of
Formulation
Scleroglucan:Dextran
(I)
1:7
(II)
8:7
(III)
1:6
(IV)
2:5
Example 1
Secondary thickener (ST) overflow from an operating Bayer plant was collected just prior to the test, divided into 1 L aliquots in clear 1 L measuring cylinders and placed in a waterbath at 75° C. Each cylinder contained approximately 83 g/L of alumina trihydrate. The products tested were added as dilute solutions one after another to the surface of the slurry and mixed well using a gang plunger. The settling rate was measured by recording the time taken for the solids interface to reach the 600 mL mark of the cylinder from when the mixing ceased. The result of the settling rate is converted to meters per hour (m/hr) in Table 2.
TABLE 2
Alumina trihydrate settling results for Example 1.
Settling Rate
Formulation
Dose (ppm)
(m/hr)
Dextran
0.7
2.46
Scleroglucan
0.7
3.94
The data in table 2 indicate that a significantly faster settling rate can be achieved with scleroglucan as the flocculant compared to an equivalent dose of dextran.
Example 2
The same method as that used in example 1 was employed. The only difference was the solids content of this slurry collected was 45 g/L. After settling the samples were left to settle for 15 minutes followed by removal of 50 mL of slurry from the surface of the slurry using a syringe. This aliquot was filtered through a pre-weighed Supor®-450 membrane filter paper. Solids were then washed with hot deionized water and dried at 100° C. The filter paper and solids were then reweighed and the mass of solids calculated. This mass is listed as “overflow solids (g/L)” in Table 3. The results are displayed in Table 3 and again show the increase in settling rate when scleroglucan is used or included in combination with dextran in a formulation. Additionally, superior (lower) overflow solids are observed when scleroglucan or formulations containing scleroglucan are used.
TABLE 3
Alumina trihydrate settling results for Example 2.
Settling Rate
Overflow
Formulation
Dose (ppm)
(m/hr)
Solids (g/L)
Dextran
0.7
4.86
0.80
Scleroglucan
0.7
5.40
0.78
(I)
0.8
6.57
0.71
Example 3
The same method as in example 2 was used. The solids content of the slurry collected for this test was 67 g/L.
TABLE 4
Alumina trihydrate settling results for Example 3.
Settling Rate
Overflow
Formulation
Dose (ppm)
(m/hr)
Solids (g/L)
Dextran
0.7
4.26
0.76
(I)
0.8
5.28
0.70
Example 4
The same method as in example 2 was used. Two separate sets of data were collected in two experimental runs. The solids content of the slurry for the individual runs in this example was 79 g/L in both cases. The top 50 mL of the slurry was sampled after 10 minutes of settling instead of 15 minutes as in example 2.
TABLE 5
Alumina trihydrate settling results for Example 4 run 1
Settling Rate
Overflow
Formulation
Dose (ppm)
(m/hr)
Solids (g/L)
Dextran
0.7
3.47
0.78
Dextran
0.7
3.63
0.87
(I)
0.64
4.42
0.87
(I)
0.8
4.58
0.89
TABLE 6
Alumina trihydrate settling results for Example 4 run 2
Settling Rate
Overflow
Formulation
Dose (ppm)
(m/hr)
Solids (g/L)
Dextran
0.35
3.33
1.17
Dextran
0.7
4.54
1.01
(II)
0.38
5.65
1.03
(II)
0.75
7.97
0.67
Example 5
Bayer plant spent liquor (200 mL) and air dried plant seed (16 g) was combined in a bottle and heated to 65° C. in a rotating water bath. Once the slurry had reached equilibrium it was transferred to a 250 mL measuring cylinder that was suspended in a water bath at 65° C. The slurry was then dosed with product, mixed thoroughly and allowed to settle for three minutes followed by removal of 50 mL of slurry from the surface of the slurry using a syringe. This aliquot was filtered through a pre-weighed Supor®-450 membrane filter paper. Solids were then washed with hot deionized water and dried at 100° C. The filter paper and solids were then reweighed and the mass of solids calculated. This mass is listed as “overflow solids (g/L)” in Table 7.
TABLE 7
Alumina trihydrate settling results for Example 5.
Overflow
Treatment
Dose (ppm)
Solids (g/L)
Undosed
0
1.98
Dextran
0.35
1.17
Dextran
0.70
1.04
(I)
0.40
1.10
(I)
0.80
0.86
Example 6
The same method as in example 5 was used in this example except that 500 ml of liquor and 40 g of seed was used for each treatment. The sampling of the slurry was conducted after 5 minutes of settling time. The settling rate was measured by the time taken for the solid interface to reach the 350 mL graduation on the cylinder once mixing had ceased.
TABLE 8
Alumina trihydrate settling results of Example 6.
Settling Rate
Overflow
Treatment
Dose (ppm)
(m/hr)
Solids (g/L)
Untreated
0
1.04
4.41
Dextran
0.7
1.29
2.71
(II)
0.7
1.57
2.71
(II)
0.7
2.05
2.51
Example 7
The same method as in example 6 was used except the solids content of the slurry in this example was increased to 120 g/L.
TABLE 9
Alumina trihydrate settling results for Example 7.
Settling Rate
Overflow
Treatment
Dose (ppm)
(m/hr)
Solids (g/L)
Untreated
0
0.84
4.97
Dextran
0.7
1.45
2.79
Dextran
1.4
1.59
2.50
(I)
0.7
1.58
2.78
(I)
1.4
1.94
1.86
(III)
0.7
1.56
2.59
(III)
1.4
1.80
1.89
(IV)
0.7
1.73
2.57
(IV)
1.4
2.14
1.91
Scleroglucan
0.7
1.99
2.01
Scleroglucan
1.4
2.48
1.39
Example 8
Plant spent liquor (1 L) and air dried plant seed (80 g) was combined in a bottle and heated to 65° C. in a rotating water bath. Once equilibrium was established the slurry was dosed with flocculant (as appropriate) mixed well and poured into a 1 L Imhoff cone. The slurry was allowed to settle in the cone for twenty minutes before allowing the slurry to discharge through the bottom hole. The discharge time was measured from when the plug was removed after the twenty minutes of settling to when all the contents of the cone had been discharged.
TABLE 10
Example 8 discharge times for settled alumina
trihydrate slurries using Imhoff cones.
Imhoff Cone
Treatment
Dose (ppm)
discharge time (seconds)
Untreated
0
66
Dextran
0.7
31
Scleroglucan
0.7
30
(I)
0.4
33
Example 9
The same method as in example 8 was used but the slurry in this example was plant secondary classification overflow slurry collected from the plant just prior to the test. The solids content of this slurry was 62 g/L.
TABLE 11
Example 9 discharge times for settled alumina
trihydrate slurries using Imhoff cones.
Imhoff Cone
Treatment
Dose (ppm)
discharge time (seconds)
Untreated
0
136
Dextran
0.7
40
Scleroglucan
0.7
11
(I)
0.8
23
Example 10
The same method as in example 9 was used in this example. The solids content of this slurry was 100 g/L.
TABLE 12
Example 10 discharge times for settled alumina
trihydrate slurries using Imhoff cones.
Imhoff Cone
Treatment
Dose (ppm)
discharge time (seconds)
Untreated
0
127
Dextran
0.7
114
(I)
0.8
112
The results from examples 8, 9 and 10 indicate that scleroglucan has an unexpected impact on the flow of settled alumina trihydrate solids.
When applied at the same dose rates as dextran, scleroglucan provides a faster settling rate, more desirable rheological properties in the settled bed and maintains similar or better performance in overflow clarity. The use of scleroglucan is effective when applied either alone, or as a blend with other polysaccharides such as dextran.
While this invention may be embodied in many different forms, there are shown in the drawings and described in detail herein specific preferred embodiments of the invention. The present disclosure is an exemplification of the background and principles of the invention and is not intended to limit the invention to the particular embodiments illustrated. All patents, patent applications, scientific papers, and any other referenced materials mentioned anywhere herein, are incorporated by reference in their entirety. Furthermore, the invention encompasses any possible combination of some or all of the various embodiments described herein and incorporated herein.
The above disclosure is intended to be illustrative and not exhaustive. This description will suggest many variations and alternatives to one of ordinary skill in this art. All these alternatives and variations are intended to be included within the scope of the claims where the term “comprising” means “including, but not limited to”. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the claims.
All ranges and parameters disclosed herein are understood to encompass any and all subranges subsumed therein, and every number between the endpoints. For example, a stated range of “1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, (e.g. 1 to 6.1), and ending with a maximum value of 10 or less, (e.g. 2.3 to 9.4, 3 to 8, 4 to 7), and finally to each number 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 contained within the range.
This completes the description of the preferred and alternate embodiments of the invention. Those skilled in the art may recognize other equivalents to the specific embodiment described herein which equivalents are intended to be encompassed by the claims attached hereto. | The invention provides methods and compositions for improving the production of alumina. The invention involves adding a product containing one or more polysaccharides to liquor within the fluid circuit of the production process, where one of the polysaccharides is scieroglucan. The use of scleroglucan can impart a number of advantages including at least some of: greater flocculation effectiveness, increasing the maximum effective dosage, faster settling rate. The production process can be a Bayer process. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to collapsible steering assemblies for automotive vehicles, and more particularly to an assembly wherein the steering shaft of the vehicle is mounted within a pair of telescoping support tubes which include a shock absorbing tube interposed therebetween along overlapping portions of the support tubes.
In automotive vehicles, the steering shaft which extends from the steering wheel of the vehicle is generally rotatably supported by the support tubes which are fixed to the vehicle body and which are telescopically mounted relative to each other. A support tube of smaller diameter is inserted into one end of a support tube of larger diameter with the interfitted ends of the support tubes overlapping over a portion of their lengths. A shock absorbing tube having mounted therein steering column balls is interposed between the support tubes at their overlapping portions. In the event of an automobile collision, the driver of the vehicle will collide with the steering wheel and the impact forces thus produced will cause the two support tubes to telescopically contract during collapse of the steering assembly with the shock absorbing tube body operating to lessen the shock imparted to the driver of the vehicle by impact with the vehicle steering wheel.
The steering assembly of a vehicle normally extends downwardly and forwardly from the driver compartment of the vehicle. Accordingly, when the body of the driver is driven against the steering wheel, the force of the impact thus produced upon the steering column involves a force component axially of the steering column as well as a force component which extends perpendicularly to the axial length of the steering column. In conventional shock absorbing steering assemblies, the shock absorbing tube which is interposed between the telescopically interfitted support tubes usually is structured with a wall of uniform thickness throughout. As a result, the steering column balls which are located within the shock absorbing tube will be pressed against the wall of the support tubes with an excessive force and as a result of the balls becoming imbedded in the support tubes there will occur a situation whereby the telescoping relative movement of the support tubes during collapse of the steering assembly will be impeded or prevented. As a result, the driver of the vehicle may be subjected to danger of injury from the shock which will occur upon impact with the steering wheel.
It has been found that in the case of a steering assembly mounted to extend downwardly and forwardly of the driver's compartment, when an automobile collision occurs the force of impact created by the body of the driver of the vehicle will be such that the steering column balls which are located upon the lower rearward portion and the upper forward portion of the shock absorbing tube will be forced into the supporting tubes to prevent the buffer action otherwise occurring during collapse of the supporting tubes.
The present invention is intended to provide a steering assembly which will be more likely to undergo the desired collapsing action when an impact force from the driver is imparted thereto during an automobile collision. The invention provides a shock absorbing tube body which will enable contraction without the steering balls being excessively driven into the surface of the supporting tubes even if a force acting at right angles to the axial direction of the steering shaft is created. Furthermore, the invention is arranged to operate in a manner so as to reduce the clearance which will ordinarily be provided between the interior and exterior telescoping supporting tube by appropriately structuring the shock absorbing tube which is interposed therebetween.
SUMMARY OF THE INVENTION
Briefly, the present invention may be described as a shock absorbing steering assembly for an automotive vehicle including a steering wheel and a steering mechanism, said assembly comprising, in combination, a collapsible steering shaft operably interconnected between said steering wheel and said steering mechanism, a first and a second support tube for said steering shaft, said first and second support tubes extending coaxially about said steering shaft, with the diameter of one of said tubes being larger than the diameter of the other of said tubes, said tubes being interfitted with their ends extending in overlapping relationship. The smaller diameter tube extends to within the larger diameter tube and a shock absorbing tube is coaxially interposed therebetween along the overlapping portions of said support tubes. The shock absorbing tube is structured with a pair of thicker wall portions at each axial end thereof with a thinner wall portion extending between said thicker wall portions. Bearing balls are mounted in the shock absorbing tube at both of said thicker wall portions and the balls are structured with a diameter which is larger than the thickness of the thicker wall portions. Accordingly, the balls will extend beyond the surface of the shock absorbing tube into abutment with the inner surface of the larger diameter support tube and the outer surface of the smaller diameter support tube. As a result, the support tubes may be collapsibly mounted to telescope relative to each other upon impact of a body against the steering wheel with the bearing balls coming into abutment with the surfaces of the support tubes in a manner to absorb shock but avoiding excessive interference with the collapsing action of the assembly.
In a preferred embodiment of the invention, the diameter of the bearing balls is dimensioned to be 0.1 millimeter greater than the thickness of the thicker wall portions of the shock absorbing tube.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.
DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a schematic illustration of an automobile steering assembly wherein there is illustrated the action of the impact forces occurring during a vehicle collision;
FIG. 2 is a schematic side view of a portion of an automobile with parts broken away to illustrate the mounting and location of a steering assembly in accordance with the present invention;
FIG. 3 is a side view partially in section showing a part of the steering assembly of the present invention;
FIG. 4 is a side view showing on an enlarged scale the shock absorbing tube body of the present invention depicted in the assembly of FIG. 3; and
FIGS. 5 and 6 are sectional views taken, respectively, along the lines V--V and VI--VI of FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1 wherein there is illustrated the reaction forces which occur upon the steering assembly during collision of an automotive vehicle, it will be seen that when the body of the driver impacts against the steering wheel of the vehicle, there will occur a component of force extending axially of the steering column as well as a component of force extending perpendicularly thereto. As a result, the steering column will tend to be bent out of axial alignment while at the same time having imparted thereto an axial collapsing force. As a result of the perpendicular component of force, the balls of a shock absorbing tube of conventional construction will be driven into the surfaces of the steering shaft support tubes in a manner which will restrict or inhibit the desired collapsing action of the steering column.
The structure of the present invention, which will be described in detail with reference to FIGS. 2-6 is intended to avoid or obviate the creation of forces tending to restrict or inhibit proper collapsing action of the steering column assembly.
Referring now to the drawings, and more particularly to FIG. 2, steering assembly 2 is mounted within a motor vehicle to extend in a forwardly descending direction from a driver's compartment 1 of the vehicle. A steering shaft 3, best seen in FIG. 3, extends between a steering wheel 4 located within the driver's compartment 1 and a joint located at the front end of the vehicle whereby the turning forces applied to the wheel 4 may be transmitted to a vehicle steering gear (not shown).
The steering shaft 3 consists of two shaft portions which are connected to each other in a generally telescopic manner. A shear pin 5 connects the two shaft portions of the steering shaft 3 so that they can smoothly rotate together. The shear pin 5 will be broken when an impact force acts thereupon so that the steering shaft 3 may contract or telescopically collapse during an automobile collision.
Around the steering shaft 3 there are provided a pair of supporting tubes 6 and 7 one being of a larger diameter and the other of a smaller diameter. The smaller diameter tube 6 is arranged to be inserted within a larger diameter tube 7 with the tubes overlapping over a portion of their lengths. With the tubes 6 and 7 thus assembled, the steering shaft 3 is rotatably supported therein.
Between the supporting tubes 6 and 7 there is retractably inserted a shock absorbing tube 8 which is pressed between the tubes 6 and 7 at their overlapping portions whereby the two supporting tubes 6 and 7 may be appropriately interconnected.
The small diameter supporting tube 6 is fixed through a bracket 10 on a vehicle inner wall located toward the forward lower portion of the driver's compartment 1. The larger diameter supporting tube 7 is fixed with a shear pin 13 through a bracket 12 to a forward wall 11 located within the driver's compartment 1.
When an impact force acts upon the steering assembly, the shear pin 13 will be broken and the large diameter supporting tube 7 will telescopically overlap the small diameter supporting tube 6 and as the tubes collapse one within the other shock will be absorbed by the shock absorbing tube 8.
The shock absorbing tube 8 is formed with a central body 17 made preferably of synthetic resinous material and with a pair of thicker wall portions 14, 14a located at each of the axial ends thereof. The thicker wall portions 14, 14a are provided with through holes 15 with steering column balls 16 being inserted within each of the through holes 15. As best seen in FIGS. 4, 5 and 6, the through holes 15 are arranged in axially extending rows, with a greater concentration of through holes 15 being provided on the lower side of the rearmost portion 14a and on the upper side of the frontmost portion 14. It will be seen that at these sections of the thick wall portion 14, 14a, four axial rows of through holes 15 are provided, with four additional rows being spaced circumferentially about the balance of each of the thick walled portions 14, 14a.
When the larger diameter supporting tube 7 moves axially relative to the tube 6, the steering column ball 16 will move relative to the tubes 6 and 7 and will make furrows on the interior or exterior walls of the tubes 6 and 7, respectively. The steering column balls 16 each have a diameter which is slightly larger than the thickness of the thick wall portions 14, 14a. Preferably, the steering column balls 16 protrude from the thick wall portions 14, 14a to about 0.1 millimeter. The balls 16 are held in place within the through holes 15, in a manner generally known, and it should be noted that the position and number of the through holes and of the steering column balls are not necessarily restricted to those illustrated in the preferred embodiment herein.
With a shock absorbing assembly structured as described herein, when an automobile is involved in a collision and the driver is caused to impact with the steering wheel 4, the shear pin 13 provided on the mounting of the large diameter support tubes 7 and the shear pin 5 provided in the steering shaft 3 will be broken and contraction of the steering column takes place. In this case, the force acting on the supporting tube 7 involves components in the axial direction as well as force components perpendicular thereto. As a result, the steering column balls 16 on the upper portion of the forward thick wall portion 14 and on the lower portion of the rearward thick wall portion 14a act so as to become forced into the exterior wall of the small diameter supporting tube 6 and the interior wall of the large diameter supporting tube 7. However, because of the thickness of the wall portions 14, 14a and the relative sizes of the balls 16, the clearance which is provided operates such that the steering column balls 16 will not be excessively forced against the surfaces of the supporting tubes 6 and 7. As a result, the supporting tube 7 having the largest diameter may move telescopically with respect to the tube 6 thereby causing the steering column to collapse without excessive scraping forces with shock being absorbed by the shock absorbing tube 8.
As described herein, where the shock absorbing tube of the present invention is utilized within the steering column, even if the component of an impact force is at right angles to the axial direction of the steering column and if such a component force acts upon the shock absorbing tube, the steering column balls are not forced into the supporting tube. When an automobile encounters a collision, the supporting tube having the larger diameter contracts securely due to proper shock absorbability and the driver will not receive harmful impact from the steering wheel.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles. | A collapsible steering mechanism is structured with a pair of telescopically interfitting support tubes having a shock absorbing tube located coaxially therebetween. A plurality of bearing balls are provided on both ends of the shock absorbing tube for engagement between the support tubes with the diameter of the bearing balls being larger than the wall thickness of the shock absorbing tube to enable desired collapse of the support tubes when an impact force is applied thereto. | 5 |
PRIORITY STATEMENT
[0001] The present invention claims priority from co-pending Provisional U.S. Patent Application No. 60/460,553, filed with the U.S. Patent Office on Apr. 4, 2003.
FIELD OF THE INVENTION
[0002] The present invention relates broadly to Wireless Local Area Networks (WLANs) and specifically to a topology for multi-channel wireless time division duplex (TDD) systems so that channel state information (CSI) may be acquired and used to optimize data throughput.
BACKGROUND
[0003] Highly functional computers have been interconnected with one another in what is termed a local area network (LAN) to enable users of individual computers within a predefined set to share files with one another. Traditional hardwired LANs are being superceded by wireless LANs (WLANs) as WLANs realize increased capacity. Data protocols for WLANs are generally organized into layers or levels of the communication system, each layer facilitating interoperability between various entities within the network.
[0004] The Institute of Electrical and Electronic Engineers (IEEE) standard for WLANs, IEEE 802.11, provides protocols for a physical (PHY) layer and a Medium Access Control (MAC) layer, shown in block diagram form at FIG. 1A. The following discussion relates to that 802.11 standard in its current form, though it is evolving. The PHY layer 21 provides protocol for the hardware of WLANs termed stations or nodes. A station may be mobile station, wireless enabled laptop or desktop personal computer, and the like. The PHY layer concerns transmission of data between those stations, and there are currently four different types of PHY layers: direct sequence spread spectrum (DSSS) 22 , frequency-hopping spread spectrum (FHSS) 23 , infrared (IR) pulse modulation 24 , and orthogonal frequency-division multiplexing (OFDM).
[0005] The MAC layer 25 is a set of protocols that maintain order in the use of the shared bandwidth or medium, and the 802.11 standard specifies two modes of communication: a compulsory Distributed Coordination Function (DCF) 26 , and an optional Point Coordination Function (PCF) 27 . A Basic Service Set (BSS) 31 is shown in FIG. 1B, and is defined as a group of stations 32 that are under the control of a single coordination function, which in 802.11 is termed a Point Coordinator PC that may also be an Access Point (AP) 33 . A BSS is roughly analogous to a group of mobile telephone users within a cell of a single base station, with the base station as the AP 33 . Conceptually, every station in a BSS can communicate with every other station in that BSS, though degradations to the transmission medium due to multipath fading or interference from nearby BSSs can result in ‘hidden’ stations. The 802.11 standard provides for two types of networks: ad hoc and infrastructure. Individual stations in the ad-hoc network are deliberately grouped as a BSS, but any station in the BSS may communicate directly with any other station in the BSS without channeling all traffic through the centralized Access Point (AP). A good example of an ad hoc network is a meeting where employees bring laptop computers together to communicate and share files. One of the stations serve as a Point Coordinator to coordinate transmissions and avoid collisions, but the PC in an ad hoc network does not act as an AP 33 that may link the BSS 31 to other BSSs or networks. Conversely, the infrastructure network uses one or more fixed network APs 33 by which wireless stations can communicate beyond the BSS 31 . These network APs are sometime used to bridge the BSS to other BSSs to form an extended service set (ESS) and/or to wired networks such as the internet or a conventional intranet as shown in FIG. 2A. If AP service areas overlap, handoffs can occur for roaming stations that move between APs similar to cellular networks commonly used for mobile telephony. In the MAC layer, the DCF operates in both ad hoc networks and infrastructure networks. However, since PCF requires an AP 33 , PCF may operate only in infrastructure networks.
[0006] Avoiding collisions (simultaneous transmissions) between stations in a BSS is complicated by the fact that while a wireless station is transmitting, it cannot monitor the transmission medium (the channel or channels) for other traffic that may interfere with its own transmissions. For example, one problem arising from the inability to listen while transmitting in WLANs is termed a “hidden node”. Assume stations A, B and C in a BSS are disposed as in FIG. 1 B, with B physically located between A and C. If stations A and C cannot communicate directly with one another due to distance, multipath fading, or some other reason, stations A and C are hidden from one another. Absent some collision control scheme, station A may listen to the channel, sense it is clear, and transmit a packet to station B. Whether or not station C is transmitting to B is unknown to A, except through coordination by the PC. Simultaneous transmissions from stations A and C to station B would result in collision and lost transmissions, since all stations in a BSS 31 communicate over the same channel.
[0007] DCF seeks to minimize collisions by prioritizing stations waiting to transmit based on a time delay basis. In DCF, each station 32 with a data message to transmit contends for the next available slot on the BSS channel during what is termed a contention period CP 29 . Time delays for various stations have a random component, but procedures ensure a waiting station moves up in priority the longer it waits. Details of the DCF prioritization protocol are described in detail below. Once a station sends its data message, which is included in a MAC Service Data Unit (MDSU), it must contend with all other waiting stations for another available slot. PCF is provided to avoid the situation where time-sensitive data from one station cannot be assembled into one MDSU, which is constrained to a maximum length. For example, station A may wish to send an audio or video clip that spans three MDSU's to station B, but contending for a separate transmission slot for each of the MDSUs would potentially result in the clip being undecipherable. While a relatively large buffer in the receiving station may store and re-assemble the separately received clip portions after a not insignificant delay, that option is generally not seen as viable in the long term due to the dual constraints of low power consumption and small physical size of wireless stations. When implemented, PCF takes priority over DCF in that a contention free period (CFP) 28 is established whereby station A may send its data messages without contending for a time slot. During the CFP 28 , other stations stand by and await either a poll by the PC during the CFP 28 or a contention period (CP) 29 in which the various stations contend for a slot as in DCF above. Additional details of PCF are provided below.
[0008] Historically, the development of WLAN systems, and wireless systems in general, have taken two paths, one focused on specifications for the PHY layer and the other for the MAC layer. For example, the IEEE 802.11(e) task group is developing MAC layer enhancement to improve MAC layer throughput regardless of physical layer throughput. The IEEE 802.11 (g) task group has developed a physical layer specification that facilitate data rates of 20+ mega bits per second (Mbps) in the 2.4 GHz. Range, but must keep MAC layer changes to a minimal. Though both working groups operate concurrently, in practice there appears little interaction between the two groups. Advantages that may be gained by a more holistic approach are never recognized by the groups' single-layer focus.
[0009] Recently, the IEEE has approved a High Throughput Study Group (HTSG) for 802.11, whose charter is to provide higher throughput than enabled by current IEEE 802.11 standards. The High Throughout Task Group (HTTG) will develop the actual standards, which appears to be the first time that modifications to the MAC and physical layers will be developed coherently since the division of those layers. A recent study showed that the current IEEE MAC and physical layers is limited to a throughput of 0.2 Mbps per 1000 byte packet per operational mode. Existing 54 Mbps modes therefore have approximately 28 Mbps throughput for a 1000 byte packet. Maintaining the same ratios, then a 108 Mbps data rate yields a throughput of 56 Mbps for a 1000 byte packet.
[0010] It is well-known that optimum capacity is achieved when Channel State Information (CSI) is known and used at both the transmitter and receiver, and that MIMO systems (multiple input/receive antennas and/or multiple output/transmit antennas) provide a substantial increase in capacity as compared to more traditional systems employing a single antenna on all transceivers. For example, knowing CSI enables a transmitter to parse data among different channels in a manner that takes advantage of the entire channel capacity on each channel, rather than allowing the time-sensitive bandwidth to be not fully used. Some communication standards such as Code Division Multiple Access (CDMA) reserve a feedback channel to provide CSI to the transmitter. Unfortunately, CSI via a feedback channel is imperfect due to feedback delays and changing channel characteristics. Regardless, the 802.11 standard does not entail a feedback channel, there are no physical layer specifications in 802.11 that are based on CSI, and some researchers believe the lack of CSI in the standard prohibits the adoption of a feedback channel in future versions of 802.11.
[0011] Thus, there is a need in the art to provide an optimum throughput/capacity topology for multi-antenna wireless systems that imposes changes that are backwards compatible with current WLAN stations.
SUMMARY OF THE INVENTION
[0012] Fortunately, there are resolutions to this problem that are embodied in the present invention. As mention above, there are no physical layer specifications in the IEEE 802.11 standard that are based on CSI at the transmitter. Operation of the Contention Free Period (CFP) is described in the IEEE 802.11(e) draft standard, herein incorporated by reference. Depending on the physical layer standard 802.11 (a), 802.11 (b) or 802.11 (g), the CFP modulation is derived from one of their operational modes.
[0013] A system according to an embodiment of this invention provide the optimum topology for a multi-antenna system dedicated to higher throughput/capacity by bundling the Point Coordination Function (PCF) operation in infrastructure mode of the current and/or enhanced IEEE MAC with PHY specifications that employ some form of coherent weighting based on CSI at the transmitter in conjunction with the corresponding optimum receiver detection based on CSI.
[0014] In one embodiment of the present invention is a method of communicating over multiple sub-channels of a WLAN. The method includes sending a control message that is not combined with a data message from a first network entity to a second network entity. The control message may be, for example, a CTS message during the CP or a poll during the CFP, but in any case the control message is to facilitate sequencing of wireless transmissions among at least two entities in a wireless network. In the inventive method, the control message is received at the second network entity, which uses it to obtain channel state information CSI. The CSI is used to determine the capacities of at least a first and second sub-channel of the wireless network, and to determine which has the greater capacity. A data message to be sent is divided into at least a first and second data message segment, wherein the relative sizes of the segments are based on the relative capacities of the sub-channels. The division itself is preferably via an eigenmode or water-filling known in the art to exploit varying capacities of sub-channels. When the first sub-channel is determined to have the greater capacity, the first data message segment will then define a greater size than the second data message segment. Further in the method and in response to receiving the control message, the second network entity sends the first data message segment over the first sub-channel, and the second data message segment over the second sub-channel of the wireless network. In this manner, CSI is obtained and used to send the segmented data message, though not necessarily the control messages.
[0015] In a particular embodiment, the first network entity is a point coordinator PC of a wireless network basic service set BSS operating during a contention free period CFP, the control message is a poll of the second network entity, and the PC may respond with an ACK message combined with a data message for the first network entity. Preferably, where the PC sends a poll of a third network entity during the same CFP as the poll of the second network entity, and the PC fails to receive a response from the third network entity within a first time period such as a SIFS, the PC then polls a fourth network entity within a second time period such as a PIFS that is no greater than twice the first time period. Where the PC receives from a network entity an ACK message combined with a data message, the PC may respond with an ACK message combined with a separate control message that signals an end of a contention free period. In the 802.11 standard, for example, such a message from the PC would be a combined ACK and CFP-End message.
[0016] Further according to another aspect of the present invention, when the method is executed during a contention free period CFP, and the first network entity is a point coordinator PC and the control message is a first poll of the second network entity, there exists an instance where a polled station does not respond to its poll. To avoid confusion with the terms above, assume an initial poll of an initial network entity or station occurs prior to the poll of the second network entity or station. Prior to sending a control message without a data portion from the PC to the second network entity, the method preferably also includes sending from the PC an initial poll without a data message to an initial network entity. Upon the PC failing to receive a response to the initial poll from the initial network entity within a first time period such as a SIFS, the PC then preferably sends, within a second time period such as a PIFS that is greater than the first time period, either a data message to the initial network entity or the first poll of the second network entity as described above.
[0017] The present invention may also be adapted for station-to-station data communications during the CFP. Where the method as summarized above is executed during a CFP, the data message in its various segments is sent over the sub-channels from the second network entity to a third network entity that is not a point controller PC. In that instance, the method further includes the third network entity sending to the second network entity an ACK message within a first time period, in response to receiving the data message segments. The PC may then send, within a period of time following the ACK message from the third entity that is less than twice the first time period, either a poll to a network entity, or a data message to the second network entity that is divided into data message segments based on CSI that is measured from at least one data message segment sent from the second network entity to the third network entity. If the PC is to allow the second and third stations to exchange multiple data messages between them, the PC will wait a PIFS before transmitting. If the PC is to allow only one cohesive data message from the second to the third entity, it need wait only one SIFS after the ACK message from the third to the second entity, or one PIFS following the data message from the second to the third entity.
[0018] In the above method, at least one of the network entities is preferably a mobile station such as a mobile phone. The term mobile station as used herein includes any portable electronic device that has a telephonic capability, such as cellular phones, portable communicators, PDAs with telephonic capability, and further includes the various accessories to the above that expand the capabilities or functionality of the mobile station with which they are coupled.
[0019] According to another embodiment of the present invention is a method of communicating data over a wireless network according to an IEEE 802.11 standard as it exists as of the priority date of this application. In this embodiment, the improvement to the 802.11 standard includes separating by at least one Short InterFrame Space SIFS a poll and a data message sent by a point controller PC while in a contention free period CFP. This allows data messages sent from the PC to be transmitted with the benefit of knowing CSI, with at least one possible exception noted below.
[0020] Preferably, CSI is also obtained during the contention period CP during a Request-to-Send/Clear-to-Send RTS/CTS exchange. In that instance, CSI is used to determine relative capacities of at least a first and second sub-channel to parse a data message from a station sending the RTS to a station sending the CTS. Specifically, a data message from the RTS-sending station is parsed into at least a first data message segment defining a first size and a second data message segment defining a smaller second size. The relative segment sizes are based on relative capacities of a first and second sub-channel as determined by the measured CSI. The larger first data message segment is sent over the higher capacity first sub-channel and the smaller second data message segment is sent over the lower capacity second sub-channel. Parsing of the overall data message is based on relative sub-channel capacity as determined by the measured CSI, such as by eigenmode or water-filling techniques known in the art.
[0021] Considering again the CFP, this embodiment of the present invention preferably restricts the PC to sending only one of five possible messages: a poll; a data message parsed according to measured CSI and transmitted among at least two sub-channels; a data message so parsed and transmitted combined with an ACK message; a CFP-End message; and a CFP-End message combined with an ACK message. Conversely, 802.11 currently allows a data message to be combined with a poll message, and does not provide that an ACK can be combined with a CFP-End message since there appears no opportunity for the latter to ever need be combined as the standard currently exists. Preferably, the PC can combine a data message only with an ACK message, else the data message may not be combined with any other message.
[0022] Preferably, the PC is allowed to send a data message without valid measured CSI to a station only upon non-receipt of a response from that same network entity to its poll within one SIFS. Most preferably, the PC can only send a data message with either valid measured CSI or estimated CSI.
[0023] Where the PC and the polled station each have a data message to send, one difference of the present invention as compared to the 802.11 standard is that the polled station is preferably allowed to send its data message first. Preferably, between the time the PC polls the station and the time the PC may next transmit, the polled station may send a data message to another station (that is not the PC) without using measured valid CSI for the channel between the polled station and the another station. In this instance, the another station is allowed an opportunity (one SIFS) to send an ACK message to the polled station prior to the time the PC is next allowed to transmit.
[0024] Another aspect of the present invention is a network entity for communicating over a wireless local area network, such as a mobile station, a point controller, an access point, or any other entity on the WLAN. The network entity includes a receiver for receiving over at least two sub-channels a control message from an entity of a wireless local area network. The control message is preferably a CTS message or a poll. The mobile station further has a processor for determining a capacity of a first sub-channel and a capacity of a second sub-channel based on channel state information CSI measured from the control message. It further includes means for parsing a data message into at least first and second segments based on the relative determined capacities of the first and second sub-channels. To best exploit the multi-channel capability in both transmit and receive functions, the mobile station has a first and second antenna having inputs coupled to an output of the means for parsing. The first antenna is for transmitting at least the first segment over the first sub-channel and the second antenna for transmitting at least the second segment over the second sub-channel. In certain embodiments, there may be a crossfeed between antennas with differential weighting for each data message segment so that each segment is actually transmitted over each sub-channel, and increased capacity is realized by the differential weights assigned to each segment.
[0025] These and other features, aspects, and advantages of embodiments of the present invention will become apparent with reference to the following description in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for the purposes of illustration and not as a definition of the limits of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The present invention is better understood in light of the following drawings.
[0027] [0027]FIG. 1A is a prior art block diagram showing MAC and PHY layer structures in 802.11.
[0028] [0028]FIG. 1B is a prior art block diagram showing BSS's connected to a wired network by a Distributions System.
[0029] [0029]FIG. 2A is a prior art timing diagram showing a CFP overlain on a regular system implementing pure DCF.
[0030] [0030]FIG. 2B is similar to FIG. 2A but reflecting changes according to the present invention.
[0031] [0031]FIG. 2C is similar to FIG. 2B but showing a different exchange of data packets.
[0032] [0032]FIG. 2D is similar to FIG. 2B but showing yet another different exchange of data packets.
[0033] [0033]FIG. 3 is a timing diagram showing a RTS/CTS Frame Exchange during the contention period.
[0034] [0034]FIG. 4 is a prior art block diagram showing a fragmentation in IEEE 802.11 MAC.
[0035] [0035]FIG. 5 is a prior art block diagram showing a IEEE 802.11 data frame format.
[0036] [0036]FIG. 6 is a prior art block diagram showing an ACK frame.
[0037] [0037]FIG. 7 is a prior art block diagram showing a PS-Poll Control Frame.
[0038] [0038]FIG. 8 is a prior art block diagram showing a RTS Control Frame.
[0039] [0039]FIG. 9 is a prior art block diagram showing a CTS and ACK Control Frame.
[0040] [0040]FIG. 10 is a graph of 2×2 Capacity curves in Rayleigh channels.
[0041] [0041]FIG. 11 is a PDSU for Optimum Topology according to the present invention
DETAILED DESCRIPTION
[0042] In the 802.11 standard, a Point Controller (PC) coordinates prioritization during the contention free period CFP 28 . The PC is functionally within the Access Point (AP) 33 of a BSS 31 and is usually physically collocated with it, so the term AP 33 is used herein to indicate either or both the AP 33 and PC. A station 32 may serve as the AP 33 and the CP. FIG. 2A is a prior art timing diagram showing transmissions sent (above the line designated 34 ) and received (below the line 34 ) by the PC according to the 802.11 standard. The time period illustrated in divided into the contention free period 28 and the contention period 29 , which together comprise a CFP Repetition interval 35 sometimes referred to as a superframe. The CFP repetition intervals 35 continue so that, when PCF 27 is in use, the CFPs 28 and CPs 29 alternate. The CFP is described with reference to FIG. 2A, and the CP is described below in conjunction with the distributed coordination function DCF 26 . Prioritization of transmissions by the various stations 32 in a BSS 31 is therefore via PCF 27 during a contention free period 28 , and via DCF 26 during the contention periods 29 .
[0043] A superframe 35 begins with a beacon frame 36 transmitted by the PC, regardless of whether PCF is active or not. The beacon frame 36 is a management frame that provides timing and protocol related parameters to the stations. Each beacon frame 36 also announces when the next beacon frame will be transmitted, so that all stations 32 are aware of superframe lengths. To enable PCF 27 to take priority over DCF 26 , the PC transmits the beacon frame 36 after a PCF Interframe Space (PIFS) 37 (about 25 μs) following the end of the last superframe 35 . Because the PIFS 37 is shorter than a DCF Interframe Space (DIFS, about 34 μs) that the DCF 26 must wait following the end of a superframe 35 , PCF 27 can take priority. A Short Interframe Spacing (SIFS) 38 spans about 16 μs and is the amount of time a station 32 is allowed to reply to the PC. Each station 32 within the BSS 31 resets a Network Allocation Vector (NAV) 41 based on the beacon frame 36 . In FIG. 2A, the NAV 41 informs the station 32 to set the beginning of the next CP 29 at the maximum span, and not to transmit during the intervening CFP 28 except under two circumstances: in response to being polled by the PC, or to send an ACK message within one SIFS after receiving a data message.
[0044] After the beacon frame 36 , the PC delays one SIFS 38 and may send any of the following: a data-only frame, a data+poll frame 42 , a poll-only frame, or a CFP-end frame. The PC maintains a list of stations for which it has data, and typically polls those stations first in order to piggyback that data with its poll of the station. Referring to FIG. 2A, the PC polls a first station and piggybacks data with that poll in a data+polling frame 42 (both data and poll are directed to the first station). Upon receiving the data, the first station responds with an acknowledgement (ACK), but itself piggybacks data (U 1 ) on its ACK in a data+ACK frame 43 . The first station is allowed a SIFS 38 to respond to the AP's poll, but may send its data (U 1 ) to any station or to the PC. [If it is sent to a station other than the PC, that station has one SIFS to send its ACK, without piggybacking data, back to the first station.]
[0045] After receiving the data+ACK frame 43 from the first station (U 1 +ACK), the PC waits one SIFS and polls another station (or the same station). In the event the previous first station sent its data (U 1 ) to the PC, the PC will piggyback an ACK for that first station in the data+poll it sends to a second station in a data+poll+ACK frame 44 (D 2 +ACK+Poll, data and poll directed to the second station, ACK directed to first station). In FIG. 2A, the second station does not respond within one SIFS, so after waiting a total of one PIFS, the PC sends a poll with data (D 3 ) to a third station in another data+poll frame 42 (D 3 +Poll, data and poll to third station). The third station responds within a SIFS with data (U 3 ) and an ACK in its data+ACK frame 43 . When the PC has no more stations to poll, or when the CFP as determined by the beacon frame 36 nears its end, the PC transmits a CFP-End frame 45 to signal all stations 32 that the CFP 28 is ended.
[0046] One drawback with the prior art, at least in certain circumstances, is that the polling frames and the data frames from the PC may be combined into a single frame (data+poll 42 or data+ACK+poll 44 ). At the time of that combined frame transmission, the PC does not know the channel state between it and the intended station. While channel state may not change significantly over a single CFP repetition interval 35 when used in a wired network, channel states change much more rapidly in WLANs. To increase capacity over a fixed bandwidth, multiple sub-channels are preferably used such as in a single input/multiple output (SIMO) communication system, a multiple input/single output (MISO) system, or most preferably a multiple input/multiple output (MIMO) system. Any of these are referred to hereafter as a MIMO system unless otherwise stipulated. The multiple sub-channels of a wireless MIMO system are each subject to rapid changes due to fading, multipath, etc., so wireless MIMO systems need to know the state of the different sub-channels to send different data portions over the strongest channels, or to partition the data to be sent into sizes that maximize the respective capacities of the various sub-channels as those sub-channels exist at the time of transmission. When the PC polls a station, it has not yet received any feedback from that station by which to measure the true channel. Since the sub-channels change rapidly, it is highly unlikely that the coherence interval (the interval over which the measured state of the channel does not change significantly) spans an entire CFP repetition interval 35 . Said another way, any measurements of the channel made in one CFP 28 are unlikely to be valid estimates of the channel during the next CFP 28 . Sending a data message combined with a poll necessarily implies sending the data either regardless of channel quality or with invalid (i.e., outside the coherence interval) estimates of the channel. Either option is a waste of bandwidth as compared to maximum capacity theory. Among other aspects, the present invention modifies the specific frame exchange of FIG. 2A to enable entities transmitting data frames to do so with knowledge of the channel, termed in the art as channel state information or CSI.
[0047] [0047]FIG. 2B is similar to FIG. 2A but shows the same substantive exchange of data frames depicted in FIG. 2A (one data frame from the AP to each of a first, second, and third station, and one data frame from the first and third stations to the AP) accomplished according to the present invention. For each of FIGS. 2B-2D, only the CFP 28 is shown and the interval between frames is one SIFS unless otherwise noted. At the start of the CFP 28 , the PC transmits a beacon frame 36 as described. The PC next transmits a polling-only frame 46 (P 1 ) that is directed to the first station. The first station has a data frame for the PC, and has the opportunity to measure actual CSI between it and the PC in the polling frame 46 . The first station uses that CSI to send a data only frame 47 back to the PC within one SIFS of the end of the polling frame 46 . The PC receives the data only frame 47 (designated U 1 ) and uses it to measure the channel between it and the first station. Using that CSI, the PC then sends its data for the first station combined with an acknowledgement that it (the PC) received the data frame from the first station in a data+ACK frame 43 . This obligates the first station to reply with an ACK only frame 48 that it received the data correctly. After a SIFS, the PC then polls the second station (P 2 ) in a polling-only frame 46 . The second station does not respond within a SIFS, so after a total delay of one PIFS, the PC polls a third station. The exchange between the PC and the third station is similar to that described between the PC and the first station for FIG. 2B.
[0048] On first glance, it appears the exchange of frames of FIG. 2B introduces an inefficiency as compared to that of FIG. 2A, due to an increased number of frames and interframe spacings. However, the poll only 46 and ACK only 48 frames are quite short, whereas any frame that includes data 42 , 43 , 44 , 47 may be substantially longer. In the present invention as embodied in FIG. 2B, the poll only frames 46 may be sent without valid CSI and all frames that include data are transmitted to maximize the available capacity of the channel. Preferably, all frames carrying data are sent with valid CSI by use of the present invention, though FIG. 2C notes an exception. While additional MAC overhead may be increased as compared to the method of 802.11, throughput is increased due to the larger size of frames with data as compared to those without. Various frame sizes and throughputs are detailed below with reference to FIGS. 5-10.
[0049] [0049]FIG. 2C is an illustration of frame exchange for the instance where the AP has data for the first and third station, and only the third station has data for the PC. The beacon 36 and polling only 46 (P 1 ) frames are as described with reference to FIG. 2B. Since the first station of FIG. 2C has no data for the PC, it does not respond to the poll within a SIFS and the PC is allowed to transmit again after a PIFS 37 . In one embodiment of the invention, the PC sends a data-only frame 27 (D 1 ) to the first station without having had an opportunity to measure CSI (since the first station did not respond to the poll within a SIFS). The first station sends an ACK only frame 48 , and the remainder of FIG. 2C is similar to FIG. 2B except the portion beginning with the frame designated ACK+U 3 . Rather than sending an ACK only frame 48 as in FIG. 2B, the third station has data for the PC, which it sends with an ACKnowledgement in a data+ACK frame 43 . Assuming there are no further stations for the PC to poll, it responds to this last transmission from the third station with an ACK+end frame 49 , wherein the ACK is directed to the third station and the CF-END portion is directed to all stations 32 of the BSS 31 .
[0050] As an alternative to the scenario described for FIG. 2C wherein the PC sends a data only frame 47 to the first station without benefit of CSI, the first station (or any station being polled but not having data to transmit to the PC) may be obliged to reply with an ACK only frame 48 in order that the PC may measure the channel. Since the PC may also not have data for the station responding to a poll with an ACK only frame 48 , there is a potential to waste bandwidth that in the cumulative becomes non-negligible. This wasting aspect may be minimized by including within the poll frame information that indicates whether or not the PC has data to send to the polled station, which may be as little as a single bit (e.g., 0 indicates no data, 1 indicates data). The polled station may disregard that information if it has data to send to the PC (as in FIG. 2B), allow a SIFS to expire without responding if the information indicates there is data (as in the exchange depicted in FIG. 2C between the PC and the first station), or respond with an ACK only frame 48 if the information indicates there is data coming from the PC (as in the exchange depicted in FIG. 2D between the PC and the second station).
[0051] [0051]FIG. 2D depicts frame exchange for additional scenarios. The beacon 36 and exchange between the PC and the first station are as in FIG. 2C. Upon polling a second station with a polling only frame 46 (P 2 ), the second station responds with a data frame to another station 51 rather than to the PC. This station-to-station data frame 51 is sent without the benefit of valid measured CSI, since there is no prior communication, within the coherence interval, from the recipient of the station-to-station data frame 51 by which to measure the channel. The recipient station then responds with an ACK only frame 48 directed back to the sending station. Though the data in frame 51 was directed toward another station, the PC still listens and uses it to measure the channel between it and the second station. Following the ACK only frame 48 directed back to the second station, the PC may send a data only frame 47 to the second station without drawing a direct response from it. The PC may wait a PIFS, to allow the second station an opportunity to send additional station-to-station data frames 51 . The second station sends an ACK only frame 48 back to the PC, which then polls a third station with a polling only frame 46 . The third station in the scenario of FIG. 2D has no data to transmit, so the PC waits a PIFS 37 and transmits a CF-END frame 45 to transition into the contention period 29 .
[0052] In any of the above instances, any of the PC or stations may have more than one frame with data to send. Due to the potential size of the data frames and the speed with which the channel may vary over time (the length of the coherence interval), it may be necessary in one instance that the sender re-acquire CSI from the last transmission of the intended recipient, and in another instance it may have negligible effect on data throughput that the sender re-use the originally measured CSI. So long as the frames in question are sent within the coherence interval established when CSI is measured, then CSI is considered valid whether or not is was measured based on a frame received immediately preceding the next frame to be sent.
[0053] The above description pertains to the CFP 28 wherein the PC controls which station in an infrastructure network may next transmit. Following is a description as to how the present invention may be used within the contention period 29 following the CFP 28 . Since the CFP 28 exists only while in the point coordination function 27 , operation within the CP 29 is within the base DCF 26 layer of MAC 25 and is detailed at FIG. 3.
[0054] DCF lies directly on the PHY layer 21 and is based on Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol, because wireless stations cannot listen for collisions while transmitting. As known in DCF, when a station has a frame with data to be transmitted, it first listens to ensure no other station is transmitting over the prescribed channel and transmits only if the channel is clear for a set period of idle time, termed a DCF-interframe space (DIFS) 38 that is longer than a PIFS. If the channel is busy, the station instead chooses a random “backoff factor” which determines a delay period 58 wait until it is allowed to transmit its data. During periods in which the channel is clear, the transmitting station decrements its backoff counter to shorten the delay period 58 so a delayed station gradually gains a higher priority to transmit. When the backoff counter reaches zero and the channel is clear for the duration of a DIFS 38 , the station may transmit its frame with data. Since the probability that two stations will choose the same backoff factor is small, collisions between data frames from different stations are minimized.
[0055] When a particular station's backoff counter reaches zero and it senses the channel is clear for an entire DIFS 38 , that station, termed the source 52 or transmitting station, first sends out a short ready-to-send (RTS) frame 53 containing information on the length of the frame with data to be transmitted. If the intended destination 54 to which the RTS 53 is directed hears it, the receiving station 54 responds with a short clear-to-send (CTS) frame 55 . Only after this exchange does the source 52 send its data frame 47 during the CP 29 . When the destination 54 receives the transmitted data frame 47 successfully (as determined in 802.11 by a cyclic redundancy check CRC), the receiving station (or PC) transmits an acknowledgment (ACK) frame 48 . This back-and-forth exchange is necessary to avoid the “hidden node” problem previously explained. If the receiving station 54 has a data frame 47 to send, it must contend for a transmit slot as above and cannot piggyback data onto its ACK frame 48 . During this process, other stations 56 defer transmission access 57 until they sense the channel is clear for a DIFS plus their backoff factor.
[0056] The present invention exploits the RTS/CTS interchange to provide valid CSI to at least the source 54 for use in transmitting the data frame 47 . The benefits of the destination 54 using CSI obtained from the RTS/CTS exchange for use in transmitting the ACK only frame 48 are relatively minor as that frame is small. Since each station is at differing times both a source 52 and a destination 54 , the means to implement the present invention are already in place and can be used for the ACK only frame 48 , even if its practical effect is merely to send an unparsed ACK frame 48 over the most robust of the available sub-channels.
[0057] There is another opportunity within the 802.11 standard by which a station may obtain valid CSI for the channel over which it intends to transmit. A listening station, such as the other station 56 of FIG. 3 that is not a source 52 or destination 54 of a particular exchange, may transmit a CTS message to itself in accordance with the standard to obtain CSI. That CSI may then be used, within the coherence interval in which it is valid, to reserve the channel and preserve a clear channel access CCA mechanism.
[0058] [0058]FIG. 4 is a prior art block diagram of a MAC Service Data Unit (MSDU) 58 , the term used to represent units of transmission in the MAC layer 25 of the 802.11 standard. As noted above, different messages maybe “piggybacked”, and the different fragments 59 of the MDSU 58 represent those different messages, which may each be independently addressed. Each fragment includes a leading MAC header 61 , a trailer 62 that includes a cyclic redundancy check CRC, and a frame body 53 between them. A single MDSU 58 may include more than one frames or fragments 59 (as in data+ACK frame, ACK+poll frame, etc.), or only one frame or fragment 59 (as in the poll only frame, data only frame, etc.)
[0059] [0059]FIG. 5 shows a more detailed view of a data only frame 47 that may be one of the fragments 59 of an MDSU 58 . The number of octets dedicated to each portion of the frame 47 is listed directly below the block. Each of FIGS. 5-9 are known in the art and consistent with the 802.11 standard, and are presented hereto demonstrate quantitative gains in using the present invention as compared to the current 02.11 standard. In the data only frame 47 of FIG. 5, the various portions of the header 61 use thirty octets, the trailer 62 uses four octets, and the body 63 carrying the substantive data may extend to 2312 octets, depending upon the amount of data to be sent. By comparison, FIG. 6 represents an ACK only frame 48 with a sixteen octet header 61 , a four octet trailer 62 , and a four octet body 63 . FIG. 7 represents a poll only frame 48 with a sixteen octet header 61 , a four octet trailer 62 , and a zero octet body 63 . FIG. 8 represents a RTS Control Frame 53 having the same relative sizes as those of the poll only frame 48 of FIG. 7 but with different header fields. FIG. 9 represents a CTS Control Frame 55 having a ten octet header 61 , a four octet trailer 62 , and a zero octet body 63 . Using these relative frame sizes, one can calculate the data throughputs for various scenarios to compare a wireless network using the topology of the present invention to the topology currently stipulated in the 802.11 standard. Those calculations as concerning the present invention are presented below.
[0060] The minimum criteria for optimum transmission topology for wireless time division duplex TDD networks are:
[0061] 1) valid CSI is present at the transmitter,
[0062] 2) eigen-mode transmission is performed, and
[0063] 3) the frame/packet is received by the intended recipient within a period less than the coherent time of the channel.
[0064] To achieve the capacities possible with the present invention, the transmitter should employ some weighting mechanism to assign frames, packets, fragments, or whatever division of the entire package to be transmitted to various sub-channels based on the measured quality of those sub-channels. Eigen-mode or waterfilling is one technique known in the art to do so, described mathematically below. For ad hoc networks and infrastructure networks during the contention period, the RTS/CTS exchange may be used. During the contention free period, the revised frame exchange described above may be employed to achieve valid CSI. In either case, the coherent weighting is done at the PHY layer 21 , so the present invention modifies both the MAC and PHY layers.
TABLE 1 Half Duplex Frame Efficiency for 1500 byte packets using Optimum Topology Configurations @ MAC SAP 6 12 24 54 100 200 Mbps Mbps Mbps Mbps Mbps Mbps CFP-Poll 95.35% 93.05% 88.75% 79.6% 68.7% 52.93% CP- 93.8% 90.9% 85.6% 74.74% 62.55% 46.2% RTS/CTS
[0065] Frame Efficiency as used in Table 1 is the time required to transmit the information portion of packet divided by the total on air time for packet. Thus, the overall capacity is found by multiplying the frame efficiency by the capacity/throughput, which are shown in Table 2 below:
TABLE 2 802.11 Capacity Requirements in bps using Optimum Topology Configurations @ MAC SAP 6 12 24 54 100 200 Mbps Mbps Mbps Mbps Mbps Mbps CFP-Poll 0.52 1.07 2.25 5.65 12.13 31.5 CP-RTS/CTS 0.533 1.10 2.34 6.02 13.32 36.1
[0066] The capacity requirements are computed as raw data rate/12 Msymbols/sec/Frame efficiency to yield the target throughput/capacity at the MAC SAP layer. The theoretical best performance for these capacity requirements can be read from FIG. 10 for a 2×2 configuration (2 input antennas, 2 output antennas) in Rayleigh fading, or computed using the formula below for any arbitrary MIMO configurations
C = log 2 [ det ( I M + γ N HH † ) ] bps / Hz
[0067] Eigen-mode transmission as noted above is described as follows. Let the singular value decomposition of H be H=UεV, where U and V are unitary matrices and ε be a diagonal matrix with positive real values on the diagonal elements representing the singular values of the channel. If the transmitted vector r is pre-multiplied by V in the transmitter and received vector is post multiplied by U H in the receiver, i.e., VrU H =V(Hx+n)U H =εx+m, where m=Vn*U H and there is no noise amplification and remains spatially white.
[0068] Because a single MAC layer must interface with disparate PHY layers, the 802.11 standard uses an additional protocol layer termed the Physical Layer Convergence Protocol (PLCP) disposed between them that is defined differently for each transmission method. The PLCP adds a preamble and a header (each of various sizes) to a PLCP Service Data Unit (PSDU), which is the portion of the complete transmission frame (PPDU or PLCP Protocol Data Unit at the PHY layer) that carries the actual data to be transmitted between stations or between the point controller PC and a station. FIG. 11 is a block diagram showing a PSDU 65 for optimum topology according to the present invention, with times and numbers of bits tailored for compatibility with the 802.11 standard as it currently is written. The present invention enables the length of a guard interval 66 a , 66 b to be selectable (to vary) based on the CSI. For certain channels, the delay spread of the channel is shorter than other time and hence not necessary to keep a fixed cyclic prefix (CP) overhead. Further, if capacity achieving codings are used, such as low density parity check codes (LDPC) or Turbo codes, then additional time is allocated at the end of the packet for iterative decoding, which is not currently available in current IEEE 802.11 standard or its amendments. This additional time is represented in the PSDU 65 of FIG. 11 as an iterative decoding signal extension 67 .
[0069] While there has been illustrated and described what is at present considered to be a preferred embodiment of the claimed invention, it will be appreciated that numerous changes and modifications are likely to occur to those skilled in the art. It is intended in the appended claims to cover all those changes and modifications that fall within the spirit and scope of the claimed invention. | An inventive method provides optimum topology for a multi-antenna system dedicated to higher throughput/capacity by bundling the Point Coordination Function (PCF) operation in infrastructure mode of the current and/or enhanced IEEE MAC with PHY specifications that employ some form of coherent weighting based on CSI at the transmitter in conjunction with the corresponding optimum receiver detection based on CSI. Specifically, CSI is measured from a control message, so data messages and control messages are separated. In the contention period of IEEE 802.11, the RTS/CTS exchange is used for CSI and the data message is sent following the CTS message. In the contention free period, a poll by the PC is separated from a data frame, which gives the polled station the first opportunity to send a data message. This change in topology results in various changes to the frame exchange format in the CFP for various scenarios of data and control messages to be exchanged. | 7 |
FIELD OF THE INVENTION
The invention relates generally to electronic circuitry and its operation and, more particularly, to the structure, control and operation of CMOS image sensing circuitry.
BACKGROUND OF THE INVENTION
CMOS image sensors are emerging as a viable alternative to CCD sensors due to the low power consumption and high integration capability of CMOS circuitry. However, CMOS imaging sensors also have various problems. One example is the so-called fixed-pattern-noise (FPN) caused by device mismatches and/or process nonuniformities. A mismatch occurs at each pixel site, and at each column read-out.
An example of a known CMOS imaging sensor is shown in FIG. 9 . The key blocks are: Pixel Block; Column Block; and Chip Output Block. The pixel Block (one for each pixel) includes the following: Photodiode PD; NMOS Transistor N 1 ; and Switches RES and SEL. The Column Block (one for each column of Pixels) includes the following: Capacitors C 1 and C 2 ; PMOS Transistor P 1 ; Switches CDS and COL; and Current sources IPIXEL and ICOL. The Chip Output Block (one for the whole chip) includes the following: PMOS Transistor P 2 ; Switch CHIP; and Current Source ICHIP.
The operation of the Pixel Block is as follows: Node IN is connected to switch RES, the cathode of photodiode PD, and the gate of NMOS transistor N 1 . Initially switch RES is closed and the voltage on node IN is VRES. Then switch RES is opened. There will be a finite charge on node IN dependent on the voltage VRES, the capacitance of photodiode PD, and the gate capacitance of NMOS transistor N 1 . The photodiode current causes the charge on node IN to be discharged and the voltage on node IN decreases. Generally imagers have a fixed integration time or period. The voltage on node IN at the end of the integration period is referred to herein as VPD.
The voltage on node IN is read out using NMOS transistor N 1 and Switch SEL, the Column Block circuit, and the Chip Output Block circuit.
FIG. 10 summarizes the position of the switches during the Integration Period and the Pixel Readout, which enables the FPN to be suppressed.
During the Integration Period, RES and SEL are open. During the Pixel Readout, the following occurs.
Readout Step 1 : RES and SEL are open, CDS, COL, and CHIP are closed to reset the Column and Chip Blocks. The voltage across C 1 will be zero. The voltage across C 2 is VP 1 gs, which is the gate to source voltage of PMOS transistor P 1 .
Readout Step 2 : SEL is closed and COL is opened. The voltage across C 1 becomes VPD−VN 1 gs (VN 1 gs=gate to source voltage of NMOS transistor N 1 ). The voltage across C 2 remains VP 1 gs.
Readout Step 3 : CDS and CHIP are opened. The voltage across C 1 remains VPD−VN 1 gs. The voltage across C 2 remains VP 1 gs.
Readout Step 4 : RES and COL are closed. The source voltage of N 1 becomes VRES−VN 1 gs. The voltage across C 1 remains VPD−VN 1 gs. Thus the gate voltage of P 1 becomes (VRES−VN 1 gs)−(VPD−VN 1 gs)=VRES−VPD. The source voltage of P 1 becomes (VRES−VPD)−VP 1 gs. The voltage across C 2 remains VP 1 gs. Thus the gate voltage of P 2 becomes (VRES−VPD)−VP 1 gs+VP 1 gs=VRES−VPD. The readout voltage OUT is VRES−VPD+VP 2 gs where VP 2 gs is the gate to source voltage of PMOS transistor P 2 . PMOS transistor P 2 is a common device used for the readout of all pixels.
Both VN 1 gs and VP 1 gs terms are canceled in this Sequential Correlated Double Sampling Technique. The N 1 and P 1 Vt terms, which are embedded in the VN 1 gs and VP 1 gs, are also canceled. Thus the effect of CMOS Vt mis-matches are suppressed with the above technique and the Fixed Pattern Noise is greatly reduced.
Readout Step 5 : CHIP is closed. The readout voltage OUT equals VP 2 gs. The rest of the switches are opened. The pixel has been reset for the next Integration Period. The system is ready for the next pixel readout.
The above description is a readout operation for one pixel. During the Integration Period for one pixel, the Column Block and Chip Output Blocks are being used for Readout of other pixels.
Some problems with the CMOS imaging sensor of FIG. 9 include the disadvantageous effect of parasitic routing capacitance caused by capacitors C 2 (thousands of them in a complete pixel array) driving the transistor P 2 , and the fact that the capacitors are typically poly/n-well capacitors which disadvantageously tend to be stray-sensitive and also suffer from a leakage problem.
It is desirable in view of the foregoing to provide for CMOS image sensing that avoids the aforementioned problems associated with known CMOS imaging sensors.
According to the invention, a single capacitor can be used for both readout and reduction of device mismatches. Such dual-purpose use of a single capacitor is facilitated by a switching arrangement. The switching arrangement connects the capacitor to a low impedance node during charge storage, thereby advantageously providing the stored charge with a stray-insensitive, leakage independent characteristic. Also, the column readout line is driven by the low impedance node, thereby advantageously reducing parasitic routing capacitance.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 illustrates pertinent portions of exemplary embodiments of an imaging sensor according to the invention.
FIG. 2 is a timing diagram which illustrates an example of the control and operation of the imaging sensor of FIG. 1 .
FIG. 3 illustrates a reset state of the imaging sensor of FIG. 1 .
FIG. 4 illustrates a read-out state of the imaging sensor of FIG. 1 .
FIG. 5 illustrates pertinent portions of further exemplary embodiments of an imaging sensor according to the invention.
FIG. 6 is a timing diagram which illustrates exemplary signals which can be used to control operations of the imaging sensor of FIG. 5 .
FIG. 7 illustrates a sampling state of the imaging sensor of FIG. 5 .
FIG. 8 illustrates a read-out state of the imaging sensor of FIG. 5 .
FIG. 9 and 10 illustrate a known CMOS imaging sensor arrangement.
DETAILED DESCRIPTION
FIG. 1 illustrates pertinent portions of exemplary embodiments of a CMOS imaging sensor according to the invention. The imaging sensor of FIG. 1 includes a pixel circuit 11 and a column read-out circuit 13 . The imaging sensor of FIG. 1 includes a plurality of circuit nodes designated as n 1 , n 2 , n 3 , n 4 , n 5 , n 6 and n 7 . The column read-out circuit 13 includes a poly/n-well capacitor C coupled between nodes n 5 and n 6 , and a buffer coupled between nodes n 4 and n 7 . The pixel circuit 11 includes a photodiode PD as is conventionally used in CMOS imaging sensors.
The imaging sensor of FIG. 1 further includes a switching arrangement including a plurality of switches for selectively interconnecting various nodes in the imaging sensor. Each switch of the switching arrangement is controlled by one of a plurality of control signals designated in FIG. 1 as Φ 1 , Φ 2 , Φ 3 , Φ 4 and Φ 5 . These control signals are also illustrated in the timing diagram of FIG. 2 . The timing diagram of FIG. 2 , taken in conjunction with FIGS. 1 , 3 and 4 , illustrates an example of the control and operation of the imaging sensor of FIG. 1 .
Referring now to FIGS. 1-3 , when Φ 1 (reset), Φ 3 (row select) and Φ 4 (hold) are high in FIG. 2 , the corresponding switches in FIG. 1 are closed, and the remaining switches controlled by Φ 2 and Φ 5 are open. Thus, at this time, the imaging sensor of FIG. 1 has the circuit configuration illustrated in FIG. 3 . At this time, the voltage across the capacitor C is:
ΔV c =V ref −( V ref −V gs,M +V off,M +V off,buf )
where V gs,M represents the gate-source voltage of the NMOS driver M, V off,M represents the DC offset of the driver M, and V off,buf represents the DC offset of the buffer.
When Φ 4 (hold) goes low and Φ 5 (column select) goes high after exposure, the sensor of FIG. 1 assumes the circuit configuration illustrated in FIG. 4 . In this configuration, the output voltage is given by:
V out = V p h - V gs , M + V off , M + V off , buf + Δ V c = V p h - V gs , M + V off , M + V off , buf + V ref - ( V ref - V gs , M + V off , M + V off , buf ) = V p h
where V ph is the voltage across the photodiode PD.
It can be seen from the foregoing that all of the mismatch offsets are stored in the capacitor C during the reset phase, and are then cancelled out in the read-out phase. That is, the operation illustrated in FIGS. 1-4 uses the reset phase, as controlled by Φ 1 to store the mismatch information into the capacitor, and the mismatch information is then cancelled out during the read-out phase controlled by Φ 4 and Φ 5 . This means that the operation described above with respect to FIGS. 1-4 can read-out only one row of the image sensor array at one exposure time. Accordingly, in applications that have a particularly long exposure time, the embodiments of FIGS. 1-4 might not be able to read out the whole image sensor array as quickly as desired.
FIG. 5 illustrates pertinent portions of exemplary embodiments of a CMOS imaging sensor according to the invention which can provide faster operation than the imaging sensor of FIG. 1 . The image sensor of FIG. 5 includes generally the same circuit elements as FIG. 1 , but has a differently designed arrangement of switches for controlling interconnection of the circuit elements. The sensor of FIG. 5 includes nodes n 11 , n 21 , n 31 and n 41 , and each of the switches in the FIG. 5 switching arrangement is controlled by one of a plurality of control signals Φ 11 , Φ 21 , Φ 31 and Φ 41 . The image sensor of FIG. 5 also utilizes two voltage references, V ref1 and V ref2 , to increase the output signal swing range.
FIG. 6 is a timing diagram which illustrates the signals Φ 11 , Φ 21 , Φ 31 and Φ 41 which control the image sensor of FIG. 5 . As shown in FIG. 6 , the image signal is read-out by operation of Φ 41 (column select) during the second pulse of Φ 11 (reset).
Referring now to FIGS. 5 and 6 , during the sampling phase, when Φ 21 (sample) and Φ 31 (row select) both go high, the image sensor of FIG. 5 assumes the circuit configuration illustrated by FIG. 7 . In FIG. 7 , the voltage across capacitor C is given by:
Δ V c =V ref2 −( V ph −V gs,M +V off,M +V off,buf ).
During the read-out phase, with Φ 11 , Φ 31 and Φ 41 all high, the image sensor of FIG. 5 assumes the circuit configuration illustrated in FIG. 8 . In this configuration, the output voltage is given by:
V out = V ref1 - V gs , M + V off , M + Δ V c + V odd , buf = V ref1 + V ref2 - V p h .
Again, the offset mismatch does not appear in the output voltage V out , which is read-out during the reset phase. Therefore, different rows of an image sensor array can partly share the exposure time illustrated in FIG. 6 .
In view of the foregoing discussion, it will be evident to workers in the art that the imaging sensor embodiments of FIGS. 1-8 are: insensitive to parasitic routing capacitance because the output nodes n 7 and n 41 are low-impedance nodes; low power sensors because they provide a true column-parallel read-out; leakage and stray insensitive although using a poly/n-well capacitor, because the n-well is connected to a low-impedance node during charge storage. Moreover, and assuming that the capacitors C within a given sensor array are well matched, charge-injection and clock-feedthrough do not present a problem because they are common-mode signals to all pixels of the array.
Although exemplary embodiments of the invention are described above in detail, this does not limit the scope of the invention, which can be practiced in a variety of embodiments. | A single capacitor (C) can be used for both readout and noise reduction in an imaging sensor. This dual-purpose use of the single capacitor is facilitated by a switching arrangement (Φ 1-Φ5 ) which connects the capacitor to a low impedance node (n 7 , n 41 ) during charge storage. The low impedance node is also used to drive a column readout line (V out ). | 7 |
BACKGROUND OF THE INVENTION
Fishing is an increasingly popular sport, with over 75 million enthusiasts involved in the United States of America. The increasing amount of fishermen and the limited fishing waters lead the way for more innovative products and methods for increasing the fishing yield in this competitive sport. Many of these new products are related to the stimulation of the olfactory, visual, and even sound senses of fish and include a wide variety of products and application methods.
Fish, especially sport-fish, are generally attracted to smaller bait-fish and anything natural that falls into or lives in the water, such as insects, frogs, crawfish, and worms. Most new developments for artificial baits are new designs or variations of previous designs which better simulate an actual bait-fish or other natural food. New color combinations are also being constantly designed and applied to existing and new baits for visual stimulation of the fish.
Fish are attracted to baits by their keen sense of smell as well as by visual means. A variety of products designed to stimulate these senses is presently available. Among these products, scent attractants are commonly used to increase the likelihood of success. These scent attractants tend to be oil or water based and therefore need to be constantly reapplied to the bait. This reapplication is necessary because the oil or water-based material dissipates as the formulation is washed away by the water. These scent attractant products are usually very messy to work with, often leaving behind oily residues on the fisherman and equipment.
Scent attractant products are also available in various other forms, such as in water-soluble polymers which attach themselves to the exterior coating of the lure as in U.S. Pat. No. 4,927,643. This type of polymer coating requires a longer drying time due to the addition of the polymer. The polymer coating also absorbs the fish attractant, preventing penetration into the lure.
Thus, there is a definite need for a scent attractant product that ca penetrate the lure and therefore does not require constant reapplication, dries quickly, and does not result in an oily mess. This invention satisfies this need by utilizing a scent with a volatile solvent which allows the scent to penetrate the bait.
Products also exist that enable the fisherman to change the color of a variety of plastic baits. This is usually accomplished by dipping the lure into a volatile solvent containing a dye. The lure is immediately removed from the solution and allowed to dry. As soon as most of the solvent has evaporated, the lure will have a different color and can be used immediately. However, in this application, some of the residual solvent or even the dye can emit a chemical odor that is offensive to the fish. Thus, there also exists a definite need for a product that can be applied by the fisherman that can both change the color of a plastic bait and which adds a long-lasting scent attractant in one simple process. The present invention also satisfies this need by utilizing the volatile solvent and scent with a dye.
SUMMARY OF THE INVENTION
The invention provides a composition for applying to a bait to attract fish or mask a scent on the bait, comprising a masking or attracting scent and a suitable volatile solvent, in the absence of a polymer. Preferably the solvent comprises between about 80-99.9% by weight of the composition, especially between about 90-99.5% by weight of the composition, and most preferably between about 97.5-99.5% by weight of the composition.
DETAILED DESCRIPTION OF THE INVENTION
The invention provides a composition for applying to a bait to attract fish or mask a scent on the bait, comprising a masking or attracting scent and a suitable volatile solvent, in the absence of a polymer. Preferably the solvent comprises between about 80-99.9% by weight of the composition, especially between about 90-99.5% by weight of the composition, and most preferably between about 97.5-99.5% by weight of the composition.
As used herein, "attract" means to incorporate a scent into a bait such that the scent is released and detected by a fish's olfactory organs to stimulate the "feed" response. By "mask" is meant to release a scent such that scents which are repulsive to a fish are less detectable by the fish.
As described herein, only "suitable" scents and solvents are within the scope of the invention. Thus, scents that are repulsive to a fish are not within the scope of the invention. Likewise, solvents which do not allow penetration into the bait for prolonged release of scent are not within the scope of the invention.
The drying time of the subject invention is preferably less than one minute. More preferably, the drying time is less than 30 seconds, especially less than about 10 seconds.
The composition of the invention can further comprise a suitable solvent soluble dye. The solvent soluble dye would readily be known to one skilled in the art and can be selected from the group consisting of basic, acid or solvent group of dyes. Common suitable examples include C.I Solvent Blue 35, C.I. Solvent Yellow 72, and C.I. Solvent Yellow 33. The composition can be applied to a bait. By "bait" is meant anything used to attract and catch a fish, for example a lure, plastic worm, or a live bait.
The invention also provides a method of attracting a fish to a bait comprising applying the subject composition to the bait and placing the bait in the presence of a fish.
As used herein, "volatile" means a solvent which penetrates into the bait rather than forming a coating on the surface of the bait. Such penetration allows the scent, which penetrates with the solvent, to be more slowly released in water.
Many volatile solvents are available that have the unique capability to penetrate a variety of plastics such as polyvinylchloride (PVC), polystyrene, urethane, and others. These solvents actually permeate into the plastic on contact and evaporate when exposed to the atmosphere. As the solvent permeates into the plastic surface, dissolved molecules such as compatible fish attractants and/or solvent-soluble dyes permeate into the plastic along with the solvent. The nonvolatile or very low volatile fish attractants and/or dyes remain with the plastic both on and below the surface after the solvent evaporates. Even though the fish attractants are considered nonvolatile, they do slowly evaporate over extended periods of time, releasing scent and taste that attract fish.
Acetone is a preferred example of a suitable solvent because of its fast evaporation characteristics and overall performance. Even though acetone is flammable, it has no harmful effects to the environment. When utilized in this invention, acetone dries in a matter of seconds, allowing for almost immediate use of the bait. When used in a fine-mist spray applicator for painted plastic or wood lures, it quickly dries with no blemishing effect to the coating.
Other suitable solvents include ketones such as methyl ethyl ketone, diethyl ketone, methyl acetone, and tetra hydro furan. Examples of esters include butyl acetate, ethyl acetate, methyl acetate, and propyl acetate. Alcohols include methyl alcohol and ethyl alcohol. Chlorinated solvents such as methylene chloride, trichloroethane, and perchlorethylene will also work. Toluene and xylene are two types of hydrocarbon solvents that will work. Although these solvents and others work, due to slow drying they are less preferred than acetone when dipped into the composition. However, when utilized in a fine mist spray, these solvents can be very effective.
Moreover, the present invention is composed of a scent attractant formulated into a volatile solvent, for the purpose of adding a penetrating scent attractant to a bait. This invention can also provide a combination of scent attractant, dye and volatile solvent designed to add a penetrating scent and cause a color change to a lure in a single process or application step. The combination of dye and scent attractant alleviates the problem of residual chemical odors left by dye and also adds a longlasting scent attractant to the lure being treated.
The scent attractor/masker, or combination of scent attractors/maskers include, for example, all scents presently utilized in the art including garlic oil, shrimp oil, anise oil, artificial and natural fish or seafood oils or extracts of worms or fish, shrimp, crabs, clams or artificial equivalents. A concentrated form of attractant is preferred to give best results. However, if too much attractant is used, the excess may not penetrate the lure completely and may leave behind an undesirable residue after the solvent has evaporated.
The following examples are intended to illustrate but not limit the invention. While they are typical of those that might be used, other procedures known to those skilled in the art may be alternatively employed. In particular, any of the above alternative formulations can be substituted for the formulations used in the Examples.
EXAMPLE I
A formulation of a garlic-scented penetrating attractant is composed of the following ingredients an percentages: garlic oil (substantially pure) (Berje, Bloomfield, N.J.), 0.5% by weight; and acetone, 99.5%. When applied, the garlic attractant remained in the bait for extended time periods.
EXAMPLE II
A formulation of an anise scented penetrating attractant is composed of the following ingredients and percentages: anise oil, 2.5% by weight; and acetone, 97.5%. when applied, the formulation remained in the bait for extended time periods.
EXAMPLE III
A formulation of a garlic scented penetrating attractant with a red dye is composed of the following ingredients and percentages: garlic oil, 0.5% by weight; C.I. Solvent Red. 24, 0.4%; and acetone, 99.1%. When applied, the formulation remained in the bait for extended time periods and the bait was dyed red.
EXAMPLE IV
A formulation of a nonflammable anise scented penetrating attractant with a blue dye is composed of the following ingredients and percentages: anise oil, 2.5% by weight; C.I. Solvent Blue 35, 0.5%; and 1,1,1 trichloroethane, 97%. When applied, the formulation remained in the bait for extended time periods and the bait was dyed blue.
EXAMPLE V
An example of an application by dipping consists of adding any of the above formulations in a bottle (normally two ounces) and dipping a lure such as a plastic worm partially into the liquid-filled container. The worm is immediately removed and allowed by dry for a few seconds. After drying, an odor is very apparent and remained for extended periods. Also a color change was observed if a dye/scent combination was used.
EXAMPLE VI
Any example of an application by non-aerosol spraying consists of adding any of the above formulations to a fine-mist spray bottle and spraying a mist on the lure of choice. Drying takes a few seconds, as shown in Example V.
Although the present processes have been described with reference to specific details of certain embodiments thereof, it is not intended that such details should be regarded as limitations upon the scope of the invention except as and to the extent that they are included in the accompanying claims. | The invention provides a penetrating scent/taste attractant for the use on fishing lures. More particularly, a scent attractant that actually penetrates the surface coating or the actual bait body is provided. A combination of a scent attractant and a dye for application to a bait to provide a penetrating scent and a permanent color change simultaneously is also provided. Also provided is a formulation for the application of a scent attractant, with or without a solvent-soluble dye, singularly dispersed or dissolved into a solvent capable of attacking the surface of an artificial bait and promoting a migration of either or both the fish-attractant and dye below the surface of the bait. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to pumps and other apparatus in wells, and more particularly to vertical positioners and torque arrestors for submersible water pumps.
Submersible centrifugal pumps powered by electric motors are commonly suspended at the end of the length of a pipe within a well. A problem common to small diameter wells in many locations is that particulate debris is present on the bottom of the well, either from its original use or with the passage of time. It is therefore necessary that a submersible pump be located some distance above debris, to avoid entrainment of it into the pump intake with consequent damage of the impellers. Normally, this is accomplished by first measuring the depth of the well and then providing only sufficient pipe to suspend the pump the desired distance above the debris. However, if the debris is particularly light it is difficult to ascertain its depth at the bottom of the well. On the other hand it is undesirable to suspend a pump too great a distance above any debris since it is advantageous to be able to "draw down" the maximum water in the well when demand exceeds the infiltration capacity of the well.
Another problem in applications such as domestic water supplies results from periodic on-off pump cycling. When the pump motor is started there is a force between the armature and field, with the result that a torsional moment is imparted to the pump housing. The pump is characteristically fitted rather closely in the well; e.g. a four inch diameter pump may be in a six inch well bore. Thus, there is a tendency for the suspended pump to both rotate and move laterally, twisting the suspending pipe and causing contact with the well bore. This effect is especially present when pumps are suspended in a well from long thermoplastic pipes.
The lateral movement and contact of the pump with the well bore can cause abrasion and eventual failure of the pump housing. Repetitive torsion may cause pipe failure and loosening of associated pipe fittings. Therefore, means to prevent such damage are required. A conventional device presently used is comprised of a collar or multiplicity of fingers extending from the pump or the pipe line near the pump. The device, often made of a resilient material such as a thermoplastic or rubber, is adjusted to the nominal diameter of the well prior to lowering of the pump into the well. Thus, the device has a tendency to rub along the sides of the well bore, thereby impeding the lowering or raising of the pump. Further, the device must be adjusted to pass by the narrowest point in the well, and if the well bore varies in diameter the device may not fully prevent movement when the pump is at its working location in the well. Still another problem results when a conventional torque arrestor is fitted to the pipe just above the pump; in many pumps the direction of rotation is such that there is a tendency for loosening of the fitting which adapts the pipe to the pump discharge.
Accordingly, there is a need for an improved means for positively locating and fixing the position of a submersible pump within a well bore, both laterally and vertically.
SUMMARY OF THE INVENTION
According to the invention, a stabilizer for a submersible pump is attached to the bottom of the pump and engages the material at the bottom of the well, thereby resisting vertical, rotational, and lateral motion of the pump. The stabilizer is of sufficient length to support the pump above debris in the well. In a preferred embodiment, the lower end of the stabilizer has an irregular cross section to increase resistance to rotational motion; and the upper end is adapted to receive and capture the bottom end of the pump, yet allow circulation of water thereabout.
In another preferred embodiment, the stabilizer is comprised of two parts and an expansible device. The upper part is attached to the pump and the lower part is attached in axially movable fashion to the upper part; the expansible device is connected between the upper and lower parts. When the lower part contacts the well bottom, the lower part's relative movement toward the upper part actuates the expansible device, thereby causing it to contact the well bore and provide lateral and rotational stability. Vertical stability is provided by the interaction of the upper and lower parts of the stabilizer.
The invention provides a simple yet effective means for both positively positioning a pump vertically and for resisting damaging torsional forces. The invention may be readily constructed out of thermoplastics or metals in economic fashion. Further, the apparatus permits easy raising and lowering of the pump since its diameter is insubstantially larger than that of the pump body during such operations. A further advantage of the invention is that it is possible in special circumstances to use piping which is of lighter weight than heretofore, since the axial weight and torsional forces are both counteracted by the invention.
Other aspects and features of the invention will be evident from the Figures and Description of the Preferred Embodiment which follows.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1: shows a pump suspended in a well bore with an attached stabilizer in engagement with the well bottom.
FIG. 2: shows a partial section of the attachment of the stabilizer to the pump body.
FIG. 3: shows a cross section of the lower end of the stabilizer along line 3--3 of FIG. 2.
FIG. 4: shows a cross section along line 4--4 of FIG. 5.
FIG. 5: shows an alternate embodiment of a stabilizer having movable parts and expansible arms for contacting the well bore.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention herein is described in terms of a submersible electric motor pump placed in a water well drilled in rock, although it may be used in other types of wells, and for other devices and structures wherein a similar problem is solved.
A well bore in which the invention is particularly usable is usually drilled in rock or otherwise has a rigid wall. Typically, there will be drilling debris remaining in the well; usually this is gravel and light sand. Over time, further quantities of sand and like material may infiltrate and accumulate at the bottom of the well. If entrained into the pump, damage can be caused, and therefore it is an object to hold the pump a sufficient distance above the bottom of the well to avoid this. In this disclosure, reference is often made to the well bottom. By this is meant any material in the well at its terminus which is capable of supporting the apparatus of the invention. Most commonly, this will comprise the coarser sand, gravel, and stone materials residing at the bottom of the well, having a consistency which allows partial penetration of the stabilizer.
The FIGS. 1-3 show a preferred embodiment of the invention and illustrate its general mode of operation. FIG. 1 shows a pump 20 suspended in a water well bore 24 by a pipe 22. The pump has a water inlet 26 at its mid point. A stabilizer 28 of the present invention is attached to the lower end 30 of the pump. The stabilizer is comprised of a rigid structure 28 fixed at its first end 34 to the lower end 30 of the pump in a manner which resists axial, lateral, and rotational motion. The second end 36 of the stabilizer is adapted to engage the bottom 38 of the well bore.
The attachment of the stabilizer to the pump is shown in more detail in FIG. 2. It may be seen that the first end 34 of the stabilizer is a hollow cylinder with one or more axial slots 40. Thus the pump body may be received within the hollow cylindrical end and a clamp 42 provides compressive force to the cylinder. Of course the cylinder is made of a material with properties which enable it to be deflected by action of the clamp and thereby capture the pump body. Tightening of the clamp causes frictional engagement with the pump sufficient for most purposes. But, a shoulder 38 is best further provided to engage the base of the pump, thereby ensuring that the cylinder will not progressively move along the pump under axial force. Keyways, pins, or the like may also be added to ensure the absence of relative axial and rotational motion. The outer diameter of the first end 34 is to be minimized so as to be less than the diameter of the well bore.
The second end 36 of the stabilizer engages the bottom 38 of the well, penetrating through lighter material until friction prevents further motion, or until heavier material is encountered. The stabilizer has an axial length sufficient to hold the pump vertically above the entrainable debris which is present or may accumulate over time. This length is determinable by experience in a particular area of the country, and typically will be 2 to 3 meters. The second end 36 of the stabilizer is preferably shaped to frictionally engage the loose material, as by increasing the surface area, to resist torsional and lateral movement.
As shown in the Figures, including FIG. 3, the lower end of the stabilizer preferably has an irregular and serrated cross section, such as the three-pointed star shape shown, to better engage the bottom of the well in a manner which will resist torsional motion. Other shapes may be used as well and in certain instances it will be found to be satisfactory to merely have a continuation of the simple hollow cylindrical shape of the first end with or without serrations such as comprise an internal or external spline. Also the second end may be of other irregular shapes, such as that of a flat panel or other like mechanical configuration which provides both a rotationally and axially stable engagement. But, while the exact configuration is optional, it is desired that the second end have a certain minimum cross sectional profile, especially if the material at the bottom is very fine and of low bearing strength. An embodiment of the second end especially suited for such material is comprised of an end furthest from the pump which has a low cross section and high area, then transitioning nearer the pump to a higher cross section; that is, a more abrupt section change than the taper shown in FIGS. 1-3. Accordingly, the stabilizer will first penetrate easily and then with great resistance, ensuring some penetration for resisting rotation, but avoiding overly great penetration to provide vertical locating.
In use, the stabilizer is fixed to the pump prior to the lowering of the pump into the well. As the pump is lowered toward the bottom of the well, the stabilizer will contact and penetrate the bottom until the weight of the pump (and a portion of the suspending pipe as well) is supported by the resistance of the bottom to further penetration. Thus the vertical location will be fixed and tensile stress on the pipe will be reduced. When the pump is activated, the reaction force of the motor starting forces will seek to move the pump both rotationally and laterally. But this motion will be resisted by the affixed stabilizer due to its engagement with the bottom.
There are some other aspects of the preferred embodiment of the stabilizer which deserve note. The stabilizer may of course be used in cooperation with other types of devices previously known. For example, as shown in FIG. 1, a lateral support 44 affixed to the upper end of the pump, or pipe adjacent thereto, may be added to further resist lateral motion. Also, it is preferred that water be allowed to circulate about the lower end 30 of the pump where the stabilizer is attached for proper cooling of this section of the pump body. Thus a cavity 46 is desirably provided at the first stabilizer end, with ingress and egress of water provided by axially extending slots 40 along the first end of the stabilizer which intercept the cavity. Of course other means may be readily used to attach the stabilizer to the pump, other than the slotted hollow cylinder shown. For example, a female socket may be permanently attached to the bottom of the pump, and a male mating portion of the stabilizer engaged with it, with threads, set screws, and the like. Further, the portion of the stabilizer structure connecting the upper and lower ends which is not intended to penetrate the bottom may be of arbitrary design, so long as it is sufficiently rigid to perform its function. And of course, to allow easy shipment the stabilizer may be comprised of two or more joinable pieces.
A further embodiment of the invention which provides increased lateral and torsional stability is shown in FIGS. 4 and 5. The stabilizer is now broken into two parts, 47 and 48, which can move axially with respect to one another. Expansible means for contacting the well bore are interposed between the parts and are actuated by relative motion of the parts. Referring to the Figures, the upper part 47 essentially has the configuration of the previously described first end 34 insofar as engagement with the pump is concerned. The lower part 48 has a lower end (not shown) which in configuration and function is like the second end 36 of the previous embodiment. The two parts are interconnected by a bushing 50 which is permanently fixed to the lower part 48 at its upper end 52 and which is slidably movable within a bore 54 in the upper part 47. The bushing has a head 58 to retain it within the bore 54 by engagement with the shoulder 60. Between the upper and lower parts are positioned two arms 62 and 62', pivoted from the upper part by pins 64. The arms are positioned so that they may be caused to pivot by the lower part's relative movement toward the upper part. Thus, it may be seen that essentially the upper part simply provides a means for positioning the lower part in a manner which enables it to movably actuate the expansible device comprised of the two arms.
As shown in the Figures, the arms are in their unactuated position when the upper and lower parts of the stabilizer are at their maximum separation. This is the configuration of the stabilizer as the pump is lowered into the well, and it is seen that the stabilizer has no greater diameter than that provided by the part which encompasses the pump body. As the pump is lowered, the bottom end of the stabilizer's lower part 48 will ultimately contact the bottom of the well and thereby cause the upper and lower parts to move relatively closer. The upper end 52 of the lower part 48 thereupon contacts arms 62-62' and causes them to pivot outwardly until they contact the well bore, as shown in phantom, the length of the arms having been selected to suit the well bore. Some further vertical motion may ensue as the arms slide vertically along the wall while the lower part of the stabilizer settles firmly at the bottom of the well. Thus the weight of the pump and pipe will actuate the expansion of the arms, by the relative motion of the parts and contraction of the stabilizer. The contact of the arms with the well bore provides resistance to torsional and lateral movement. As the arms contact the bore and thus can move outwardly no further, further relative motion of the lower part of the stabilizer is also stopped, and vertical support to the pump is thereby provided. Of course, a portion of the vertical load may be borne by the expansible device and suspending pipe as well, but it is desirable that the major portion of the load be borne by the stabilizer. As shown in the embodiment of FIGS. 4 and 5, there is relative rotary motion possible between the upper part and the lower part of the stabilizer. Thus the lower part of the stabilizer provides only lateral and vertical resistance. An alternate embodiment would comprise means to prevent this relative motion, such as an irregularly-shaped or keyed bushing 50 and bore 54. In such an embodiment, the resistance to torsional motion would be provided cooperatively by the expansible device and the lower part of the stabilizer.
When the pump and stabilizer are sought to be removed from the well, vertical motion is applied to the pump body, as through the suspending pipe or other conventional means. Whereupon, the reverse of the previously described motion is caused by force of gravity on the elements, and the expansible means retract, allowing free withdrawal from the well.
In the embodiment of FIGS. 4 and 5, the lower part of the stabilizer is shown as a hollow cylinder, in accord with the discussion attending the prior embodiment. One or more holes 66 are provided through the wall of the cylinder to allow venting of the cylinder when it is sought to remove the pump from the well. Thus, when the hollow cylinder is designed to be open at its bottom end where it contacts the well bottom, the release of entrapped air, water, mud, and the like will be aided. Of course, other shapes of openings may be provided. The expansible means shown in the embodiment of FIGS. 4 and 5 is comprised of two arms. A greater number of arms may be used, as well as other expansible devices, such as elastomeric cylinders or other known spring and gravity actuated devices which increase in diameter upon the application of axial force and decrease in diameter in its absence. The stabilizer may be constructed out of metals, thermoplastics, or other materials which have durability within the medium of the well. Most preferably it is economically made mostly out of a thermoplastic such as ABS plastic for a water well of the domestic type.
While our invention has been described in the foregoing preferred embodiment and alternatives, it should not be so limited, as it is capable of many modifications and changes in construction and arrangement which may be made without departing from the spirit and scope of the invention. | A stabilizer for a submersible pump in a well bore is attached to the pump so that it extends from the lower end of the pump toward the bottom of the well. When placed in the well, the stabilizer engages sandy debris in the well and thereby positions the pump vertically, while at the same time providing resistance to lateral and torsional forces caused by on-off cycling of the pump. One embodiment of the stabilizer further has expansible means which are actuated by contact of the device with the well bottom; the expansible part provides additional lateral and torsional support when the pump is in place, but conveniently retracts for easy removal of the pump as it is lifted. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to a process for preparing aliphatic anhydrides from divinyl ethers and carboxylic acid.
Divinyl ethers may be synthesized by the process disclosed by Gillis and Schimmel, J. Org. Chem., 25, 2187-90 (1960).
Anhydrides are usually made by displacing chloride from an acid chloride by a carboxylate ion or by heating an acid with an acidic dehydrating agent, such as phosphorus pentoxide or acetic anhydride. These reactions require either high temperatures or generate inorganic waste products.
SUMMARY OF THE INVENTION
The invention is a process for preparing aliphatic anhydrides comprising contacting a divinyl ether with a carboxylic acid in the presence of a catalytic amount of a strong acid. The invention is further a process for preparing alkylidene dicarboxylates, which are intermediates in the above preparation of aliphatic anhydrides.
DETAILED DESCRIPTION OF THE INVENTION
The divinyl ethers used in this invention are represented by the formula ##STR1## wherein R' is separately in each occurrence a substituted or unsubstituted C 1-10 aliphatic group or a hydrogen atom. Preferably, the starting divinyl ether is symmetrical. Most preferably, the starting ether is diisopropenyl ether, which is represented by the formula ##STR2##
In the invented process, these divinyl ethers are reacted with carboxylic acids. Preferably, the carboxylic acids are substituted and unsubstituted aliphatic carboxylic acids. More preferably, the carboxylic acid is 1 to 10 carbon alkenyl or alkyl carboxylic acids. Most preferably, the carboxylic acid is acetic acid, propionic acid or acrylic acid.
The reactants should be combined in about a 2 to 1 ratio of the carboxylic acid to the dialkenyl ether.
In this process carboxylic acid reacts with divinyl ether to form an intermediate which is an alkylidene dicarboxylate, formula II below, and a carbonyl compound, formula III below. This reaction can be represented by the following equation, A: ##STR3## wherein R' is separately in each occurrence a 1 to 10 carbon aliphatic group or a hydrogen atom; and R is a substituted or unsubstituted aliphatic group. More preferably, R is C 1-10 alkenyl or C 1-10 alkyl.
The alkylidene dicarboxylate (II) is a fairly stable compound which is an intermediate in the production of the anhydride. The compound decomposes with heating to the anhydride (I) and the carbonyl compound (III). This can be represented by the following equation, B: ##STR4##
R and R' are defined above. Where the most preferred divinyl ether, diisopropenyl ether is used, the reaction can be described by the following equations: ##STR5##
In this embodiment of the invention, the carbonyl compound (III) is acetone.
The reaction is catalyzed by a strong acid. Preferable strong acids are those with a pK a of less than 2.0. More preferably, the acids are oxalic acid and trifluoroacetic acid. The catalyst is preferably used in mole ratios of catalyst to divinyl ether of between about 0.5 to 1.0 and 0.001 to 1.0 and more preferably between about 0.1 to 1.0 and 0.01 to 1.0. Other strong acids which may be used include sulfuric acid, hydrochloric acid and nitric acid.
Where the carboxylic acid is a liquid, no solvent is necessary, although a solvent may be used. Suitable solvents include inert organic solvents, preferably chlorinated aliphatic compounds, most preferably those represented by the formula CCl X Y 4-x , wherein x is an integer from 1 to 4 inclusive and Y is hydrogen or deuterium. To get the desired product of the anhydride, the most preferable solvents are those represented by the formula CCl 3 Y. It has been discovered that the use of CDCl 3 and CHCl 3 as solvents speeds up the reaction and aids the decomposition of the alkylidene dicarboxylate to the anhydride.
Some alkylidene dicarboxylates are more stable than others, and elevated temperatures are required for some of the alkylidene dicarboxylates to decompose to give the anhydride product. Elevated temperatures mean herein above 60° C., preferably between 120° C. and 500° C. Between 25° C. and 60° C., the alkylidene dicarboxylate is the predominant product of this reaction. Between 60° C. and 120° C. both the alkylidene dicarboxylate and the aliphatic anhydride are produced in substantial amounts.
Where propionic anhydride is the desired product, the reaction temperature should be between about 30° C. and 200° C. It is preferable to run the reaction between about 80° C. and 180° C., and most preferable to run it at a temperature between about 120° C. and 150° C. In the most preferred range, almost all of the alkylidene dicarboxylate decomposes.
When acrylic acid is the starting carboxylic acid, the alkylidene dicarboxylate formed is very stable. In order for the alkylidene dicarboxylate of acrylic acid to decompose to the anhydride, the alkylidene dicarboxylate of acrylic acid is preferably exposed to temperatures, up to about 400° C.
When the alkylidene dicarboxylate is subjected to gas pyrolysis, it decomposes to the anhydride and the carbonyl compound. The pyrolysis step can be run between about 250° C. and 400° C. Thus, the process for preparing the anhydride disclosed herein can additionally include a gas pyrolysis step wherein a particularly stable alkylidene dicarboxylate is decomposed to give the anhydride. Where acrylic acid is the starting carboxylic acid, the alkylidene dicarboxylate produced decomposes to acrylic anhydride and the carbonyl compound when subjected to gas pyrolysis.
When acrylic anhydride is the desired product, CDCl 3 or CHCl 3 are the preferred solvents as acrylic anhydride is a significant portion of the product when those solvents are used.
This process can be run at autogeneous pressure. The process may be run in an inert gas atmosphere, such as N 2 .
Specific Embodiments
The practice of the instant invention is further illustrated by the following examples. These embodiments and examples are not intended to limit the scope of the instantly claimed invention.
EXAMPLE 1
Reaction of Diisopropenyl Ether with Acetic Acid
Diisopropenyl ether (4.9 g, 0.05 mole, 97 percent pure) and acetic acid (6.0 g, 0.10 mole) were combined in a round-bottom flask outfitted with a condenser, thermometer and N 2 blanket, and refluxed (60° C.) for 2 hours. Gas chromatographic analysis showed the reaction had not gone to completion based on acetic acid remaining. Two drops of trifluoroacetic acid were added and the reaction went to completion with the formation of two major products, acetic anhydride and 2,2,-propane diacetate (alkylidene dicarboxylate). The volatiles were removed on a rotary evaporator and the two major products constituted 95 percent of the gas chromatograph area in a ratio of 1:1.4, acetic anhydride to 2,2,-propane diacetate.
This example demonstrates the catalytic effect of the strong acid and the products which result from the reaction.
EXAMPLE 2
Reaction of Diisopropenyl Ether with Propionic Acid
Propionic acid (3.9 ml, 0.052 mole) was added dropwise to stirring diisopropenyl ether (2.55 g, 0.026 mole) in a 25-ml, 3-neck round-bottom flask equipped with condenser, dropping funnel, thermometer and N 2 blanket. Oxalic acid (50 mg) was added causing an immediate rise in temperature from 25° C. to 38° C. The reactants were allowed to react at 25° C. for 68 hours. Thereafter, the temperature of the reaction mixture was raised to 60° C. and kept there for 72 hours. This reaction was followed by gas chromatography as samples of the mixture were taken periodically.
The reaction did not reach completion after 72 hours at 60° C. Heating at 60° C. enhanced formation of both the propionic anhydride and the 2,2-propane dipropionate (the alkylidene dicarboxylate). Table I shows the gas chromatographic data relative to the amounts of alkylidene dicarboxylate and aliphatic anhydride produced.
TABLE I______________________________________Gas Chromatographic Results forthe Reaction of Diisopropenyl Etherwith Propionic Acid atModerate Temperature (60° C.) Area % Alkylidene DicarboxylateTime Temp Propionic (2,2-propane-(hr) (°C.) Anhydride dipropionate)______________________________________.sup. 0.sup.a 25 0.33 0.63.sup. 0.sup.b 25 1.54 1.89 1 25 2.84 4.2968 25 9.73 26.26.sup. 1.5.sup.c 60 13.45 32.7418 60 18.32 39.8424 60 20.14 42.6542 60 20.08 52.7872 60 15.10 66.06______________________________________ .sup.a Without oxalic acid catalyst. .sup.b With catalyst. .sup.c At the change in temperature, time is recorded as starting from 0.
EXAMPLE 3
Reaction of Propionic Acid and Diisopropenyl Ether at Elevated Temperatures
Diisopropenyl ether (7.42 g, 0.076 mole) and oxalic acid (0.056 g, 0.06 mmole) were combined in a reaction vessel like that used in Example 2. Propionic acid (11.2 ml, 0.15 mole) was added dropwise with stirring and the reaction mixture was held at 35° C. with an ice bath. Upon completion of the addition, the reaction mixture was heated to 60° C. for 23 hours. Thereafter the temperature was raised to 100° C. for 23 hours and then 140° C. for 5 hours, after which gas chromatography and nuclear magnetic resonance indicated the reaction was complete.
The reaction was followed by gas chromatography and the data relative to the amounts of alkylidene dicarboxylate and aliphatic anhydride produced are compiled in Table II.
TABLE II______________________________________Gas Chromatographic Results forthe Reaction of Diisopropenyl Etherwith Propionic Acid atElevated Temperature (60° C.-140° C.) Area % Alkylidene DicarboxylateTime.sup.a Temp Propionic (2,2-propane-(hr) (°C.) Anhydride dipropionate)______________________________________0 25 1.20 1.920 60 2.11 4.430.17 60 3.38 10.130.33 60 4.54 12.320.5 60 5.40 14.780.67 60 6.26 17.141.0 60 7.40 19.791.5 60 8.22 21.582.5 60 9.75 24.973.5 60 10.55 26.5417.5 60 15.92 39.3519.5 60 16.29 40.7725.5 60 16.96 43.5828.0 60 15.78 44.421.0 100 16.50 45.422.0 100 16.65 45.244.0 100 17.54 45.136.5 100 18.56 44.8920.0 100 25.42 35.6123.0 100 27.35 35.441.0 140 39.14 17.552.0 140 45.04 6.254.0 140 53.52 1.395.0 140 57.23 0.87______________________________________ .sup.a At each increment in temperature, time is recorded as starting fro 0.
These data show that the 2,2-propane dipropionate and propionic anhydride concentrations increase at 60° C. with the former forming more rapidly and reaching its maximum concentration after 28 hours. At 100° C. the 2,2,-propane dipropionate reaches its maximum concentration after about 1 hour, thereafter it starts to decompose to propionic anhydride.
EXAMPLE 4
Preparation of Propionic Anhydride from Propionic Acid and Diisopropenyl Ether
A solution of oxalic acid (0.23 g, 0.003 mole) in propionic acid (29.0 ml, 0.39 mole) was added dropwise with stirring to diisopropenyl ether (18.38 g, 0.188 mole) at 0° C. to 10° C. in a 100-ml reaction flask equipped as described in the above examples. The flask was placed in a preheated (65° C.) oil bath to begin the reaction. The temperature was gradually increased to 120° C. and the reaction was followed by gas chromatography. Upon completion of the reaction, the anhydride concentration, as measured by gas chromatography, was 97 percent and no 2,2-propane dipropionate was present in the product. The data relative to the amounts of alkylidene dicarboxylate and aliphatic anhydride generated by this test are compiled in Table III.
TABLE III______________________________________Gas Chromatographic Results forthe Reaction of Diisopropenyl Etherwith Propionic Acid Area % Alkylidene DicarboxylateTime Temp Propionic (2,2-propane-(hr) (°C.) Anhydride dipropionate)______________________________________0 25 0.70 0.820 60 1.73 3.1517 60 14.71 32.585 90 20.56 43.155 110 21.22 38.857 110 26.74 44.3217 120 63.80 --______________________________________
EXAMPLE 5
Reaction of Acrylic Acid and Diisopropenyl Ether
Diisopropenyl ether (105.9 g, 1.03 moles, 95.5 percent pure) was placed in a 500-ml, 3-neck flask fitted with a magnetic stirrer, thermometer, condenser and dropping funnel with a pressure equalizing side-arm. p-Methoxyphenol (0.025 g, 0.002 mole) was added as an inhibitor and oxalic acid (0.96 g, 0.01 mole) was added as a catalyst. Acrylic acid (165.7 g, 2.3 moles) containing 200 ppm p-methoxyphenol was added slowly to the reaction vessel by the dropping funnel. An ice bath was used to keep the reaction mixture temperature between 22° C. and 25° C. during the addition. The reaction was followed by periodically removing samples and analyzing them by gas chromatography. After 2 days, the reaction mixture had a constant composition. After distillation, 101.0 g of 95 percent by gas-liquid chromatography area of 2,2-propane diacrylate (a 51 percent isolated yield) were recovered. Only traces of acrylic anhydride were observed throughout the reaction. The p-methoxyphenol was added to inhibit polymerization. Later testing determined its use was unnecessary.
EXAMPLE 6
Pyrolysis of 2,2-Propane Diacrylate
Microliter quantities of 2,2-propane diacrylate were pyrolyzed in the injection block of a Hewlett-Packard 5712A gas chromatograph at temperatures ranging from 250° C. to 400° C. Gas chromatographic analysis of the pyrolysates showed that the concentration of the acrylic anhydride in the reaction mixture had increased significantly.
EXAMPLE 7
Effect of CDCl 3 on Reaction of Acrylic Acid with Diisopropenyl Ether
Acrylic acid (1.47 g, 0.02 mole), diisopropenyl ether (0.99 g, 0.01 mole) and oxalic acid (0.008 g, 8.9×10 -5 moles) were mixed in a nitrogen-filled 10-ml volumetric flask. A 30-μl aliquot of this mixture was transferred to a nuclear magnetic resonance tube, mixed with CDCl 3 (0.5 ml), methylene chloride (10 μ) and tetramethylsilane. After 24.5 hours, the sample in the nuclear magnetic resonance tube showed that the reaction was almost complete as the acid was nearly consumed. The amount of acrylic anhydride produced was 1.5:1 to that of the 2,2-propane diacrylate. Conversely the mixture in the original volumetric flask had a much lower conversion of reactants to products and almost no anhydride. After 14 days, the amount of acrylic anhydride in the nuclear magnetic resonance tube increased while that in the volumetric flask did not. The ratio of acrylic anhydride to 2,2-propane diacrylate was 3.3:1.
The CDCl 3 has some solvent effect on the formation of an anhydride over the alkylidene dicarboxylate. The product mix is also affected by the length of time of the reaction in that yield of anhydride increases with time.
EXAMPLE 8
Effect of CDCl 3 on the Reaction of Propanoic Acid with Diisopropenyl Ether
As a point of comparison for following the formation of propionic anhydride distillative isolation, nuclear magnetic resonance and gas chromatographic analysis were performed on the initial reaction mixture of Example 4. The nuclear magnetic resonance spectrum in CDCl 3 showed an absence of diisopropenyl ether, low levels of the 2,2-propane dipropionate and high levels of propionic anhydride and acetone. During the nuclear magnetic resonance analysis, the sample had undergone a color change from colorless to dark yellow. Gas chromatographic analysis on the initial reaction mixture and on the sample used for nuclear magnetic resonance gave the following reactant/product distribution:
TABLE IV______________________________________ AlkylideneArea % Anhydride Dicarboxylate______________________________________Initial (neat) 0.70 0.80After nmr (CDCl.sub.3) 1.48 0.05______________________________________
There is a solvent effect with CDCl 3 which causes decomposition of the alkylidene dicarboxylate to the anhydride and acetone. | The invention disclosed herein is a process for preparing aliphatic anhydrides comprising contacting a divinyl ether with carboxylic acid in the presence of a catalytic amount of a strong acid. The invention is further a process for preparing alkylidene dicarboxylates, which are intermediates in the above preparation of aliphatic anhydride. | 2 |
FIELD OF INVENTION
[0001] In one aspect, the present invention is concerned with a treatment where it is desired that an active agent is designed to be released in a pulse at a time point some time after administration of the active agent. The present invention is particularly suited to administering an agent which may be released whilst a subject is sleeping. As well as treating certain conditions by a particular regime, the invention also provides novel formulations for a delayed, followed by a pulsed release of drug.
BACKGROUND TO THE INVENTION
[0002] Time-dependent release mechanisms of drugs have been described in the literature for tablet, pellet and capsule formulation utilising a wide range of physicochemical and physicomechanical strategies. The common feature of all such formulations is that they are activated by contact with fluids following ingestion by the patient and the drug will be released at the predetermined time after administration. Only after the formulations come into contact with gastric fluids does the ‘clock’ start. Drug release subsequently takes place at a predicted time, although it will be appreciated that since the dosage unit will be travelling through the GI tract during the lag period, drug release will necessarily be at some unknown GI tract site. Using such formulation strategies, it will be possible to design delivery systems capable of releasing drugs according to chronotherapeutic principles and targeting release to the circadian rhythm of disease states (Stevens H N E, Chronopharmaceutical Drug Delivery. J Pharm Pharmac., 50 (s) 5 (1998))
[0003] However, many of the formulations in the art rely on complex structures which can add to the cost of the manufacture of the drug and/or can be subject to malfunction leading to incorrect/inappropriate administration of the drug.
[0004] It is amongst the objects of the present invention to obviate and/or mitigate at least one of the aforementioned disadvantages.
[0005] It is amongst the objects of the present invention to provide a formulation which may be easily and/or cheaply manufactured and which allows for an active agent to be administered in a short pulse, following a period of delay following administration.
SUMMARY OF INVENTION
[0006] The present inventors recognised a need to be able to administer, for example, a pharmaceutically active agent to a subject in a manner such that a delayed release of the pharmaceutically active ingredient could be achieved, followed by a pulsed delivery of the agent. Although this may have been possible using prior device/methods known in the art, many such devices/methods were highly complex and there is distinct advantage in providing a simpler press-coated tablet formulation.
[0007] One particularly preferred embodiment relates to treating subjects who wake during the night, but have no or little difficulty in initially falling asleep, commonly termed sleep maintenance insomnia. In a preferred embodiment therefore, the formulations of the present invention are for treating sleep maintenance insomnia. Such formulations therefore comprise a pharmaceutically active agent for inducing and/or facilitating sleep. Typically this may be a sedative or hypnotic agent, such as a benzodiazepine, chloral hydrate, melatonin and analogues thereof, zolpidem, zopiclone or zaleplon.
[0008] Thus, in a first aspect, the present invention provides a sleep inducing and/or maintaining formulation agent such as a sedative or hypnotic agent, formulated as a component of a press-coated tablet for treating sleep maintenance insomnia, wherein the formulation is intended to be administered immediately prior to a subject going to sleep (i.e. when a subject goes to bed at night for a prolonged period of sleep, such as 6-10 hours and hence is distinguished over shorter sleeping periods) and wherein the hypnotic agent is substantially not released from the formulation for a period between 1-8 hours, such as 1.5-4 hours after administration of the formulation to the subject and thereafter the agent is released from the formulation as a pulse such that at least 70-90%, for example 80% of the agent within the formulation is released within 5-80 mins, such as 10-45, or 10-30 mins.
[0009] In a further aspect there is provided a method of treating sleep maintenance insomnia, the method comprising administering a press-coated tablet comprising a sleep inducing agent, such as a sedative or hypnotic agent to a subject, immediately before the subject intends sleeping, wherein the formulation substantially delays release of the drug for 1-8 hours, such as 1.5-4 hours following administration of the formulation and thereafter the drug is released in a pulse over a period of 5-80 mins, such as 10-45 or 10-30 mins.
[0010] Typically delayed release of the active agent is achieved by providing a press-coated tablet comprising a delayed release layer surrounding a core comprising the active agent. The delayed release layer may comprise a wax and a low-substituted hydroxypropyl cellulose (L-HPC), such as LH-11, or LH-21.
[0011] In a further aspect, the present invention provides a press-coated tablet formulation for a delayed, followed by a pulsed release of an active agent, the tablet comprising
[0000] (a) a core comprising the active agent(s) together with an excipient(s); and
(b) a delayed release layer surrounding the core and comprising a wax and L-HPC in a ratio of 40:60 to 60:40 w/w; wherein the delayed release layer substantially delays release of the active agent within the core for between 1-8 hours, such as 1.5-4 hours after administration of the tablet by a subject and thereafter a pulsed release of the active agent from the core occurs, such that at least 70% of the active agent in the core is released within 5-80 mins, such as 10-40 or 10-30 mins.
[0012] The active agents of the above aspect include any active agent for which delayed followed by pulsed release is desirable. In a preferred embodiment of the invention, the active agent is a pharmaceutically acceptable active agent and includes pharmaceutical and veterinary active agents (often referred to as drugs). In other embodiments, the active agent includes agrichemical agents (such as fertilizers, herbicides, pesticides and fungicides), active agent used in the exterminating industry (such as toxins and poisons), and active agents used in industrial manufacturing (such as catalysts or catalytic quenchers).
[0000] The press-coated tablets of the present invention may be used to treat one or more of the following conditions/disorders or diseases:
[0013] Central Nervous System disorders, e.g. Neurogenic pain, stroke, dementia, Alzheimer's disease, Parkinson's disease, neuronal degeneration, meningitis, spinal cord injury, cerebral vasospasm, amyotrophic lateral sclerosis
[0000] Cardiovascular disease, hypertension, atherosclerosis, angina, arterial obstruction, peripheral arterial disease, myocardial pathology, Arrhythmia, Acute Myocardial Infarction, Angina, Cardiomyopathy, Congestive heart failure, Coronary artery disease (CAD), Carotid artery disease, Endocarditis, Hypercholesterolemia, hyperlipidemia, Peripheral artery disease (PAD)
Genitourinary Disorders; erectile dysfunction, urinary organ diseases benign prostatic hypertrophy (BPH), Renal tubular acidosis, diabetic nephropathy, glomerulonephritis, glomerulosclerosis, urinary tract infection, faecal incontinence
Ocular disease glaucoma, blephartitis, ocular hypertension, retinopathy, conjunctivitis, scleritis, retinitis, keratitis, corneal ulcer, iritis, Chorioretinal inflammation, macular edema, Xerophthalmia
Pulmonary disease asthma, pulmonary hypertension, acute respiratory distress syndrome, COPD, emphysema, pneumonia, tuberculosis, bronchitis, Acute Bronchitis, Bronchiectasis, Bronchiolitis, Bronchopulmonary Dysplasia, Byssinosis, Coccidioidomycosis (Cocci), Cystic Fibrosis, Influenza, Lung Cancer, Mesothelioma
Metabolic diseases; Hypercalciuria, Hyperglycemia, Hyperinsulinemic hypoglycemia, Hyperinsulinism, Hyperlysinuria, Hypoglycemia
Exocrine and Endocrine; Addison's disease, Hypoaldosteronism, cushing's syndrome, diabetes, Goitre, Hyperthyroidism, Hypothyroidism, Thyroiditis, pancreatitis
Hepatic disorders, Hepatitis, Non-alcoholic fatty liver disease, cirrhosis, hepatic cancer, Primary sclerosing cholangitis, primary biliary cirrhosis, Budd-Chiari syndrome,
Autoimmune and Inflammatory diseases, multiple sclerosis rheumatoid arthritis, psoriasis, diabetes, sarcoidosis, Addison's Disease, Alopecia greata, Amyotrophic Lateral Sclerosis, Ankylosing Spondylitis, polyarticular Arthritis, Atopic allergy, topic Dermatitis, Autoimmune hepatitis, Celiac disease, Chagas disease, Coeliac Disease, Cogan syndrome, Crohns Disease, Cushing's Syndrome, Diabetes mellitus type 1, Endometriosis, Eosinophilic fasciitis, Fibromyalgia/Fibromyositis, Gastritis, Glomerulonephritis, Graves' disease. Guillain-Barrë syndrome (GBS), Hashimoto's encephalitis, Hashimoto's thyroiditis, Haemolytic anaemia, Idiopathic Inflammatory Demyelinating Diseases, Idiopathic pulmonary fibrosis, interstitial cystitis, Juvenile idiopathic arthritis, Juvenile rheumatoid arthritis, Kawasaki's Disease, Lichen sclerosus, Lupus erythematosus, Ménière's disease, Myasthenia gravis, myositis, Narcolepsy, Pernicious anaemia, Perivenous encephalomyelitis, Polymyalgia rheumatica, Primary biliary cirrhosis, Psoriatic Arthritis, Reiter's syndrome, Rheumatoid fever, Sarcoidosis, Schizophrenia, Sjögren's syndrome, Spondyloarthropathy, Ulcerative Colitis
Musculoskeletal disorders: osteoarthritis, osteoporosis, Osteonecrosis, Arthritis, Paget's Disease Bursitis, Costochondritis, Tendonitis
Skin disorders; Acne, alopecia, candidiasis, celluliltis, dermatitis, eczema, epidermolysis bullosa, erythrasma, herpes, erysipelas, Folliculitis, impetigo, ringworm, scabies, Tinea, Trichomycosis
ENT disorders; Otitis, sinusitis, laryngitis, pharyngitis, laryngitis, meniere's disease, labyrinthitis,
Others: acute and chronic pain, viral infection, cancer, laryngitis, mastoiditis, myringitis, otitis media, rhinitis, sinusitis, Sialadenitis, Retropharyngeal Abscess, Tonsillopharyngitis,
Gastro-Intestinal Disorders
[0014] Irritable bowel syndrome (IBS) necrotizing entercolitis (NEC) non-ulcer dyspepsia, chronic intestinal pseudo-obstruction, functional dyspepsia, colonic pseudo-obstructioduodenogastric reflux, gastroesophageal reflux disease, ileus inflammation, gastroparesis, heartburn, constipation—(e.g. constipation associated with use for medications such as opioids), colorectal cancer, colonic polyps, diverticulitis, colorectal cancer, Barretts Esophagus, Bleeding in the Digestive Tract, Celiac Disease, Colon Polyps, Constipation, Crohns Disease, Cyclic Vomiting Syndrome, Delayed Gastric Emptying (Gastroparesis), Diarrhea, Diverticulosis, Duodenal Ulcers, Fecal Incontinence, Gallstones, Gas in the Digestive Tract, Gastritis, Gastroesophageal Reflux Disease (GERD), Heartburn, Hiatal Hernia, Hemochromatosis, Hemorrhoids, Hiatal Hernia, Hirschsprung's Disease, Indigestion, Inguinal Hernia, Lactose Intolerance, Peptic Ulcers, Polyps, Porphyria, Primary Biliary Cirrhosis, Primary Sclerosing Cholangitis, Proctitis, Rapid Gastric Emptying, Short Bowel Syndrome, Stomach Ulcers, Ulcerative Colitis, Ulcers, Whipples Disease
Exemplary active agents for use in the pharmaceutical and veterinary applications of the invention include analgesics, anaesthetics, anticonvulsants, antidiabetic agents, antihistamines, anti-infectives, antineoplastics, antiparkinsonian agents, antirheumatic agents, appetite stimulants, appetite suppressants, blood modifiers, bone metabolism modifiers, cardiovascular agents, central nervous system depressants, central nervous system stimulants, decongestants, dopamine receptor agonists, electrolytes, gastrointestinal agents, immunomodulators, muscle relaxants, narcotics, parasympathomimetics, sympathomimetics, sedatives, and hypnotics.
Said Active Agent or Agents May be Selected from the Following:
Gastro Drugs
[0015] Antacids—aluminium hydroxide, magnesium carbonate, magnesium trisilicate, hydrotalcite, simeticonealginates,
Antispasmodics—atropine sulphate, dicycloverine hydrochloride, hyoscine butylbromine, propantheline bromide, alverine citrate, mebeverine hydrochloride,
Motility stimulants—metoclorpramide, domperidone
H2—Receptor antagonists—Cimetidine, famotidinenizatidine, ranitidine
Antimuscarinics—pirenzepine
Chelates—Tripotassium dicitratbismuthate, sucralfate,
Prostaglandin analogues—misoprostol
Aminosalicylates—balsazide sodium, mesalazine, olsalazine, sulphasalazine
Corticosteroids—beclometasone dipropionate, budenoside, hydrocortisone, pednisolone,
Affecting immune response—ciclosporin, mercaptopurine, methotrexate, adalimumab, infliximab
Stimulant Laxatives—bisacodyl, dantron, docusate, sodium picosulfate,
Drugs affecting biliary composition and flow—ursodeoxycholic acid
Bile acids sequestrants—colestyramine,
Oxyphencyclimine, Camylofin, Mebeverine, Trimebutine, Rociverine, Dicycloverine, Dihexyverine, Difemerine, Piperidolate Benzilone, Mepenzolate, Pipenzolate, Glycopyrronium, Oxyphenonium, Penthienate, Methantheline, Propantheline, Otilonium bromide, Tridihexethyl, Isopropamide, Hexocyclium, Poldine, Bevonium, Diphemanil, Tiemonium iodide, Prifinium bromide, Timepidium bromide, Fenpiverinium Papaverine, Drotaverine, Moxaverine 5-HT3 antagonists (Alosetron, Cilansetron), 5-HT4 agonists (Mosapride, Prucalopride, Tegaserod) Fenpiprane, Diisopromine, Chlorbenzoxamine, Pinaverium, Fenoverine, Idanpramine, Proxazole, Alverine, Trepibutone, Isometheptene, Caroverine, Phloroglucinol, Silicones, Trimethyldiphenylpropylamine Atropine, Hyoscyamine Scopolamine (Butylscopolamine, Methylscopolamine), Methylatropine, Fentonium, Cimetropium bromide primarily dopamine antagonists (Metoclopramide/Bromopride, Clebopride, Domperidone, Alizapride), 5-HT4 agonists (Cinitapride, Cisapride),
Proton pump inhibitors Omeprazole, lansoprazole, pantoprazole, esomeprazole, rabeprazole sodium,
opioids and opiod receptor antagonists—e.g. codeine, morphine, loperamide, diphenoxylate, methylnaltrexone bromide
Analgesic
[0016] Acetaminophen Diclofenac Diflunisal Etodolac Fenoprofen Flurbiprofen Ibuprofen Indomethacin Ketoprofen Ketorolac Meclofenamate Mefenamic Acid Meloxicam Nabumetone Naproxen Oxaprozin Phenylbutazone Piroxicam Sulindac Tolmetin Celecoxib Buprenorphine Butorphanol Codeine Hydrocodone Hydromorphone Levorphanol Meperidine Methadone Morphine Nalbuphine Oxycodone Oxymorphone Pentazocine, Propoxyphene Tramadol codeine
Sleep Drugs
[0017] Hypnotics—Nitrazepam, Flurazepam, Loprazolam, Lormetazepam, Temazepam, Zaleplon, Zolpidem, Zopiclone, Chloral Hydrate, Triclofos, Clomethiazole, Quazepam, triazolam Estazolam Clonazepam, Alprazolam, Eszopiclone, Rozerem, Trazodone,
Amitriptyline Doxepin, Benzodiazepine drugs, melatonin, diphenhydramine and herbal remedies such as Valerian
Cardiovascular Medicines
[0018] Cardiac glycosides—Digoxin, digitoxin,
Phosphodiesterase Inhibitors—enoximone, milrinone
Thiazides and related diuretics—bendroflumethiazide, chlortalidone, cyclopenthiazide, inapamide, metolazone, xipamide
Diuretics—furosemide, bumetanide, torasemide,
Potassium sparing diuretics and aldosterone antagonists—amiloride hydrochloride, triamterene, weplerenone, spironolactone,
Osmotic diuretics'mannitol
Drugs for arrhythmias—adenosine, amiodarone hydrochloride, disopyramide, flecainide acetate, propafenone hydrochloride, lidocaine hydrochloride,
Beta adrenoreceptor blocking drugs—propanalol, atenolol, acebutolol, bisprolol fumarate, carvedilol, celiprolol, esmolol, lebatolol, metoprolol tartrate, nadolol, nebivolol, oxprenolol, pindolol, solatol, timolol,
Hypertension—ambrisentan, bosentan, diazoxide, hydralazine, iloprost, minoxidil, sildenafil, sitaxentan, sodium nitroprusside, clonidine, methyldopa, moxonidine, guanethidine monosulphate, doxazosin, indoramin, prazosin, terazosin, phenoxybenzamine, phentolamine mesilate,
Drugs affecting the renin-angiotensin system—Captropril, Cilazapril, Enalapril Maleate, Fosinopril, Imidapril, Lisinopril, Moexipril, Perindopril Erbumine, Quinapril, Ramipril, Trandolapril, Candesartan Cilexetil, Eprosartan, Irbesartan, Losartan, Olmesartan Medoxomil, Telmisartan, Valsartan, Aliskiren.
Nitrates, calcium channel Blockers and antianginal drugs—Glyceryl trinitrate, Isosorbide Dinitrate, Isosorbide Mononitrate, Amlodipine, Diltiazem, Felodipine, Isradipine, Lacidipine, Lercanidipine, Nicardipine, Nifedipine, Nimodipine, Verapamil, Ivabradine, Nicorandil, Ranolazine,
Peripheral Vasodilators and related drugs—Cilostazol, Inositol Nicotinate, Moxisylyte, Naftidrofuryl Oxalate, Pentoxifylline,
Sympathomimetics—Dopamine, Dopexamine, Ephedrine, Metaraminol, Noradrenaline Acid Tartrate, Norephidrine Bitartrate, Phenylephidrine,
Anticoagulants and Protamine—Heparin, Bemiparin, Dalteparin, Enoxaparin, Tinzaparin, Danaparoid, Bivalirudin, Lepirudin, Epoprostenol, Fondaprinux, Warfarin, Acenocoumarol, Phenindione, Dabigatran Etexilate, Rivaroxaban, Protamine Sulphate,
Antiplatelet Drugs—Abciximab, Asprin, Clopidogrel, Dipyridamole, Eptifibatide, Prasugrel, Tirofiban,
[0019] Fibrinolytic and antifibrinolytic Drugs—Alteplase, Reteplase, Streptokinase, Tenecteplase, Urokinase, Etamsylate, Tranexamic Acid,
Lipid Regulating Drugs—Atorvastatin, Fluvastatin, Pravastatin, Rosuvastatin, Simvastatin, Colesevam, Colestyramine, Colestipol, Ezetimibe, Bezafibrate, Ciprofibrate, Fenofibrate, Gemfibrozyl, Acipmox, Nictotinic Acid, Omega three fatty acid compounds, Ethanolamine Oleate, Sodium Tetradecyl Suphate.
CNS Drugs—Benperidol, Chlorpromazine, Flupentixol, Haloperidol, Levomepromazine, Pericyazine, Perphenazine, Pimozide, Prochlorperazine, Promazine, Sulpiride, Trifluoperazine, Zuclopenthixol, Amisulpride, Aripiprazole, Clozapine, Olanzapine, Paliperidone, Quetiapine, Riperidone, Sertindole, Zotepine, Flupentixol, Fluphenazine, Olanzapine Embonate, Pipotiazine Palmitate, Risperidone, Zuclopenthixol Decanoate, Carbamazepine, Valproate, Valproic acid, Lithium Carbonate, Lithium Citrate, Amitriptyline, Clomipramine, Dosulepin, Imipramine, Lofepramine, Nortriptyline, Trimipramine, mianserin, Trazodone, Phenelzine, Isocarboxazid, Tranylcypromine, Moclobemide, Citalopram, Escitalopram, Fluoxetine, Fluvoxamine, Paroxetine, Sertraline, Agomelatine, Duloxetine, Flupentixol, Mirtazapine, Reboxetine, Trytophan, Venflaxine, Atomoxetine, Dexametamine, Methylphenidate, Modafinil, Eslicarbazepine, Ocarbazepene, Ethosuximide, Gabapentin, Pregabalin, Lacosamide, Lamotrigine, Levetiracetam, Phenobarbital, Primidone, Phenytoin, Rufinamide, Tiagabine, Topiramate, Vigabatrin, Zonisamide, ropinirole, Rotigotine, Co-Beneldopa, Levodopa, Co-Careldopa, Rasagiline, Selegiline, Entacapone, Tolcapone, Amantidine, Orphenadrine, Procyclidine, Trihexyphenidyl, Haloperidol, Piracetam, Riluzole, Tetrabenazine, Acamprosate, Disulfiram, Bupropion, Vareniciline, Buprenorphine, Lofexidine, Donepezil, Galantamine, Memantine, Rivastigimine.
Anti-Infectives—Benzylpenicillin, Phenoxymethylpenicillin, Flucloxacillin, Temocillin, Amoxicillin, Ampicillin, Co-Amoxiclav, Co-Fluampicil, Piperacillin, Ticarcillin, Pivmecillinam, Cephalosporins, Cefaclor, Cefadroxil, Cefalexin, Cefixime, Cefotaxime, Cefradine, Ceftazidime, Cefuroxime, Ertapenem, Imipenem, Meropenem, Aztreonam, Tetracycline, Demeclocycline, Doxocycline, Lymecycline, Minocycline, Oxytetracycline, Tigecycline, Gentamicin, Amikacin, Neomycin, Tobramycin, Erythromycin, Azithromycin, Clarithromycin, Telithromycin, Clindamycin, Chloramphenicol, Fusidic Acid, Vancomycin, Teicoplanin, Daptomycin, Linezolid, Quinupristin, Colistin, Co-Trimoxazole, Sulpadiazine, Trimethoprim Capreomycin, Cycloserine, Ethambutol, Isoniazid, Pyrazinamide, Rifabutin, Rifampicin, Streptomycin, Dapsone, Clofazimine, Metronidazole, Tinidazole, Ciproflaxacin, Levoflaxacin, Moxifloxacin, Nalidixic Acid, Norflaxine, Orflaxacin, Nitrofurantoin, Methenamine Hippurate, Amphotericin, Anidulafungin, Caspofungin, Fluconazole, Flucytosine, Griseofluvin, Itraconzole, Ketoconazole, Micafungin, Nystatin, Posaconazole, Terbinafine, Voriconazole, Abacavir, Didanosine, Emtricitabine, Lamivudine, Stavudine, Tenofovir Disoproxil, Zidovudine, Atazanavir, Darunavir, Fosamprenavir, Indinavir, Lopinair, Nelfinavir, Ritonavir, Saquinavir, Tipranavir, Efavirenz, Etravirine, Nevarapine, Enfuvirtide, Maraviroc, Raltegravir, Aciclovir, Famciclovir, Inosine Pranobex, Valaciclovir, Cidofovir, Gangciclovir, Foscarnet, Valgangciclovir, Adefovir Dipivoxil, Entecavir, Telbivudine, Amantadine, Oseltamivir, Zanamivir, Palivizumab, Ribavirin, Artemether, Chloroquine, MefloquinePrimaquine, Proguanil, Pyrimethamine, Quinine, Doxycyclin, Diloxanide Furoate, Metronidaziole, Tinidazole, MepacrineSodium Stibogluconate, Atovaquone, Pentamidine Isetionate, Mebendazole, Piperazine,
Other:
[0020] Benztropiprocyclidine biperiden, Amantadine Bromocriptine Pergolide Entacapone Tolcapone Selegeline Pramipexole, budesonide, formoterol, quetiapine fumarate, olanzapine, pioglitazone, montelukast, Zoledromic Acid, valsartan, latanoprost, Irbesartan, Clopidogrel, Atomoxetine, Dexamfetamine, Methylphenidate, Modafinil, Bleomycin, Dactinomycin, Daunorubicin, Idarubicin, Mitomycin, Mitoxantrone, Azacitidine, Capecitabine, Cladribine, Clofarabine, Cytarabine, Fludarabine, Flourouracil, Gemcitabine, mercaptopurine, methotrexate, Nelarabine, Pemetrexed, Raltitrexed, Thioguanine, Apomorphine, Betamethasone, Cortisone, Deflazacort, Dexamethosone, Hydrocortisone, Methylprednisolone, Prednisolone, Triamcinolone, Ciclosporine, Sirolimus, Tacrolimus, Interferon Alpha, Interferon Beta,
[0021] In a particularly preferred embodiment the active agent is designed to treat sleep maintenance insomnia and as such the active agent is a sedative or hypnotic, such as zolpidem, Zaleplon or Zopiclone.
[0022] The term “active agent” is understood to include solvates (including hydrates) of the free compound or salt, crystalline and non-crystalline forms, as well as various polymorphs. For example, the active agent can include all optical isomers of the compounds and all pharmaceutically acceptable salts thereof either alone or in combination threo isomers can be indicated as “threo” and the combined erythro isomers as “erythro”.
[0023] In accordance with the invention, formulations are provided which are to be taken by a subject and which do not initially administer the active agent when the subject first takes the formulation. However, at a later time point the agent is administered to the subject as a “pulse” of agent.
[0024] In relation to the treatment of sleep maintenance insomnia, the subject takes a formulation in accordance with the invention and which comprises a sleep inducing/maintaining agent. Initially, the agent is substantially not released from the formulation, but after a period of time, for example, when a subject suffering from sleep maintenance insomnia may be expected to wake up, the agent is released in a pulse, so as to treat the subject and reduce the likelihood of them waking up through the night. It is desired that the agent is released in a pulse like manner so that the drug does not remain in the subject's system for a long period of time, in order to ensure that the subject is able to wake up at a suitable time in the morning and not to feel drowsy, a common side-effect of sleep inducing/maintaining agents.
[0025] The L-HPC is preferably LH-11 or LH-21, especially LH-11. LH-11 and LH-21 are particular types of L-HPC and may be obtained from Shin-Etsu Chemical Co., Ltd., Tokyo, Japan. L-HPCs are insoluble in water and comprise a glucose backbone which is substituted to a minimal extent by hydroxypropyl groups LH-11 is mostly fibrous and has a mean particle size of 55 μm. LH-11 has a hydroxypropyl content of around 11% and a molecular weight of around 130,000. LH-21 is moderately fibrous and has a mean particle size of 45 μm. LH-21 has a molecular weight of around 120,000 and a hydroxypropyl content of around 11%
[0026] The wax may be any suitable wax such beeswax, carnuba wax, microcrystalline wax, hydrogenated castor oil. A particularly preferred wax is a glyceryl ester, such as glycerol behenate.
[0027] In a preferred formulation of the present invention as defined herein above, the wax and L-HPC are present in a ratio of 40:60 to 60:40 w/w. More preferably the ratio is 45:55 to 55:45 w/w, or 50:50 w/w. The skilled addressee will appreciate that with appropriate variation of the ratio, the delay in drug release can be tailored for a particular application. For example, a 50:50 w/w ratio of glycerol behenate as a wax, with LH-11 as the L-HPC employed as a delayed release layer in accordance with the present invention, is observed to provided a delayed release of approximately 3 hours. However, the same ratio with LH-21 as the L-HPC provides a delay in release of only 2 hours. Also reducing the amount of wax in comparison to the L-HPC is observed to reduce the delay significantly and conversely increasing the amount of wax to L-HPC ratio results in a significant increase in the delay of release. Thus with appropriate control of the ratio of wax to L-HPC and the type of wax/L-HPC, it is possible to control the time delay in release of the active agent, from a press-coated tablet comprising a delayed release layer surrounding a core comprising the active agent.
[0000] The delayed release layer surrounding the core may also comprise an amount of an active agent or agents, which may be the same or different to the active agent in the core, and which is designed to be released during dissolution/disintegration of the delayed release layer.
[0028] The subject to be treated is an animal, e.g. a mammal, especially a human.
[0029] The amount of active agent to be administered will be sufficient to be therapeutic or prophylactic. By therapeutic or prophylactic is meant one capable of achieving the desired response, and will be adjudged, typically, by a medical practitioner. The amount required will depend upon one or more of at least the active compound(s) concerned, the patient, the condition it is desired to treat or prevent and the formulation. However, it is likely to be in the order of from 1 μg to 1 g of compound per kg of body weight of the patient being treated.
[0030] Different dosing regimes may likewise be administered, again typically at the discretion of the medical practitioner. The formulation of the present invention may allow for at least daily administration although regimes where the compound(s) is (or are) administered more infrequently, e.g. every other day, weekly or fortnightly, for example, are also embraced by the present invention.
[0031] By treatment is meant herein at least an amelioration of a condition suffered by a patient; the treatment need not be curative (i.e. resulting in obviation of the condition). Analogously references herein to prevention or prophylaxis herein do not indicate or require complete prevention of a condition; its manifestation may instead be reduced or delayed via prophylaxis or prevention according to the present invention.
[0032] For use according to the present invention, the compounds or physiologically acceptable salt, solvate, ester or other physiologically acceptable functional derivative thereof described herein are presented in a press-coated tablet form comprising the compound or physiologically acceptable salt, ester or other physiologically functional derivative thereof, together with one or more pharmaceutically acceptable excipients therefore and optionally other therapeutic and/or prophylactic ingredients. Any excipients are acceptable in the sense of being compatible with the other ingredients of the formulation and not deleterious to the recipient thereof.
[0033] The tablets of the present invention may be prepared using reagents and techniques readily available in the art and/or exemplary methods as described herein.
[0034] The tablets include those suitable for oral, rectal or vaginal administration. The tablets may, where appropriate, be conveniently presented in discrete dosage units and may be prepared by any of the methods well known in the art of pharmacy.
[0035] Compressed tablets may be prepared by compressing the core tablet in a suitable machine an active compound in a free-flowing form such as a powder or granules optionally mixed with a binder, lubricant, inert diluent, lubricating agent, surface-active agent or dispersing agent. The core tablet is subsequently coated with the materials for forming the delayed release layer. Tablets may be optionally coated, for example, by way of a further gastro-resistant coating.
[0036] Tablets suitable for rectal administration are most preferably presented as unit dose suppositories. Suitable carriers include cocoa butter and other materials commonly used in the art. The suppositories may be conveniently formed by admixture of a tablet with the softened or melted carrier(s) followed by chilling and shaping in moulds.
[0037] The tablets of the present invention may be prepared using pharmaceutical processes namely by direct compression or by granulation processing and final tableting. The process may comprise the steps of initially forming a core comprising the active agent and subsequently surrounding core with the delayed release layer. The core may be formed by dispersing one or more active agents with one or more excipients, such as a cellulose ether, typically a L-HPC, such as LH-21.
[0038] The delayed release layer may be formed by melting the wax component and subsequently admixing the other components including the L-HPC. The mixture may then be allowed to cool and solidify before being ground and/or forced through a sieve, in order to achieve granules of the size range 500 μm-1 mm. The core may then be coated with the delayed release layer material by direct compression. Typically the core is sandwiched between top and bottom layers of the delayed release material and hence completely surrounds the core.
[0039] The tableting for the formulation of tablets may be conducted using an apparatus ordinarily employed for the formation or granulation of tablets. Examples may include single-punch tableting machine, rotary tableting machine and tableting tester.
[0040] Tableting is conducted usually under a pressure of 50 to 300 MPa, preferably 80 to 200 MPa. At a pressure less than 50 MPa, the resulting tablet may have insufficient hardness, which disturbs easily handling, while pressures exceeding 300 MPa may serve to cause a delay in disintegration.
[0041] The core and/or delayed release layer may include a filler, such as a water insoluble filler, water soluble filler, and mixtures thereof. The water insoluble filler, may be a calcium salt or talc. Exemplary water soluble fillers such as water soluble sugars and sugar alcohols, preferably lactose, glucose, fructose, mannose, galactose, the corresponding sugar alcohols and other sugar alcohols, such as mannitol, sorbitol, and xylitol.
[0042] The filler in the delayed release layer can be the same or different as the filler in the core composition, if any. For example, the core composition can include a water soluble filler while the press coat composition can include a water insoluble filler.
[0043] Other excipients can also be present in the core and/or delayed release layer, including lubricants (such as talc and magnesium stearate), glidants (such as fumed or colloidal silica), pH modifiers (such as acids, bases and buffer systems), and pharmaceutically useful processing aids. It will be appreciated that such other excipients may be the same or different in the core and delayed release layer, if any.
[0044] In a preferred embodiment of the invention, the core components (active agent and optional excipients) are blended together and compressed into suitable cores. The blending can take place in any order of addition. Preferably, the cores are blended by starting with the smallest volume component and then successively adding the larger volume components.
[0045] The tablet can be further coated with optional additional coatings. The additional coatings can be pH-dependent on pH-independent, aesthetic or functional; where the coating is a gastro-resistant coating (intended to prevent release in the stomach), the ‘clock’ or time for delayed release, as defined herein, will not start until gastric emptying occurs and dissolution of the gastro-resistant coating takes place (as can be determined, for example, by employing scintigraphy studies). The time taken for dissolution of the gastro-resistant coating together with the delay from the time-delay layer will ensure drug release in the lower reaches of the intestine, particularly the distal ileum and/or colon. Such additional coatings preferably include film forming materials. For subjects who may additionally find it difficult to go to sleep, the delayed release layer and/or additional coating may include a sleep inducing agent for immediate release.
DETAILED DESCRIPTION
[0046] The present invention will now be further described by way of example and with reference to the figure which show:
[0047] FIG. 1 shows the release profile of a drug from a tablet comprising glycerol behenate and LH-11 in a 50/50 w/w ratio in a delayed release layer;
[0048] FIG. 2 shows the release profile of a drug from a tablet comprising glycerol behenate and LH-21 in a 50/50 w/w ratio in a delayed release layer;
[0049] FIGS. 3 and 4 show the release profile of a drug from a tablet comprising glycerol behenate and LH-11 ( FIG. 3 ) and LH-21 ( FIG. 4 ) in 30:70 w/w ratio, in a delayed release layer;
[0050] FIG. 5 shows Gamma Scintigraphy Images showing release of delayed release formulation of Zolpidem;
[0051] FIG. 6 shows Pharmacokinetic analysis of drug levels in plasma, in 6 subjects; and
[0052] FIG. 7 shows the release profile of a tablet comprising a delayed release layer of 50/50 w/w glycerol behenate/LH32.
FORMULATION FOR TREATING SLEEP MAINTENANCE INSOMNIA
1. Clinical Need
[0053] This formulation profile was designed as a treatment for people that fall asleep initially, then reawaken and are unable to sleep 2-3 hours later.
2. Methods
2.1. Core Tablet Blend and Core Tablet Compression
[0000]
(i) 1 g Zolpidem tartrate, 5.1 g ac-di-sol, 2.0 g lactose and 0.9 g magnesium stearate. Powder mix of the above, except magnesium stearate, for 10 min in turbula mixer, then magnesium stearate added and all mixed for further 5 min.
(ii) 90 mg core tab blend-compressed in a 6.9 mm die/punch set at 1 ton for 10 seconds.
(iii) Tablets are stored in amber glass bottle until use.
2.2. Granules (to Surround Core Tablet)
[0000]
(i) Glycerol behenate (GB) and LH-11 weighed into tared weigh boats according to Table 1:
[0000]
TABLE 1
Excipient
Weight (g)
GB
10
LH-11
10
(ii) GB placed in a glass beaker on a hot plate set at 100° C. Once the GB melted, LH-11 added gradually whilst stirring until a uniform mix is achieved.
(iii) The mix stirred continuously until cooled to room temperature. The granules are left for at least 30 min at room temperature before the next step.
(iv) The cooled granules forced through a 1 mm sieve (using a spatula and a brush) and collected on a 500 μm sieve so that the granules used are in the size range 500 μm-1 mm.
(v) Granules stored in amber glass screw-top jar until use.
2.3. Formulation Compression
[0000]
(i) A 13 mm die and matching flat-faced punches used to compress the formulation. For 6 tablets, 12×250 mg granules (to surround core tablet) are weighed into tared weigh boats.
(ii) 250 mg granules placed onto the lower punch, the core tablet dropped on and centralised (centralising tool) before placing the other 250 mg granules on top.
(iii) The formulation is compressed at 5 ton for 2 minutes in a 13 mm die/punch set.
2.4. Dissolution
[0065] Dissolution performed in 900 ml sodium phosphate buffer (0.01 M, at pH7) at 37° C., with UV analysis at 242 nm.
3. Results (50:50, GB:LH-11)
[0066] As can be seen from FIG. 1 , a delay of approximately 3 hours is observed, followed by a rapid pulsed release of drug.
4. Supporting Data
[0067] 4.1. LH-21 instead of LH-11 (50:50, GB:LH-21)
As can be seen in FIG. 2 , substituting LH-11 for LH-21, results in a decrease in the delay of release time. Such a decrease may not be desired for all envisaged applications.
4.2. 80:20, GB:LH-11
[0068] No release of zolpidem core tablet over 12 hours, data not shown.
4.3. 80:20, GB:LH-21
[0069] No release of zolpidem core tablet over 12 hours, data not shown.
4.4. 30:70, GB:LH-11
[0070] As can be seen in FIG. 3 , reducing the glycerol behenate to LH-11 ratio results in a significant decrease in the delay of release time.
4.5. 30:70, GB:LH-21
[0071] As can be seen in FIG. 4 , reducing the glycerol behenate to LH-21 ratio results in a significant decrease in the delay of release time.
Using LH-21 in the outer granules instead of LH-11 releases the core tablet approximately 30 min earlier in both examples shown above.
Extraction Method/Analysis of Plasma Levels of Zolpidem
Materials
[0072] Human plasma, lithium heparin, origin USA: Sera laboratories international Ltd, Bx H911239 Zolpidem tartrate
DEE: Fisher laboratory reagent grade Bx 1097413
NaOH: prepared using Q3 water and NaOH: Sigma Aldrich, reagent grade beads, 97% Bx 01209BH
Method
[0073] vortex blank plasma
add 400 ul blank plasma to glass screw cap tubes
Calibration
[0074] Blank preparation—to be prepped before standards
add 100 ul mobile phase to 400 ul blank plasma
vortex 10 secs
add 50 ul 1M NaOH
[0075] vortex 10 secs
add 4 mL DEE and vortex 3 mins (note: DEE decanted from bottle fresh every day)
pipette tips changed after every addition of mobile phase/DEE
Standard Preparation
[0076] Starting with lowest concentration standard, vortex standard
Add 100 ul standard to 400 ul blank plasma
Vortex 10 secs
Add 50 ul 1M NaOH
[0077] Vortex 10 secs
Add 4 mL DEE and vortex 3 mins (note: DEE decanted from bottle fresh every day)
Pipette tips changed after every addition of standard/DEE
Centrifuge samples 3 mins at 2000 rpm
Remove top layer into clean labelled glass screwtop tube using glass pipette
Evaporate to dryness under nitrogen at 40° C. (also used RVC to evaporate, 40° C., 100 mbar, 25 mins)
Reconsititute in 100 ul mobile phase. Allow to stand for 30 mins and then vortex 3 mins
Transfer to HPLC vial with insert
Sample Preparation
[0078] Vortex samples to mix
Add 500 ul sample to glass screwtop tube
Add 50 ul 1M NaOH
[0079] Vortex 10 secs
Add 4 mL DEE and vortex 3 mins (note: DEE decanted from bottle fresh every day)
Pipette tips changed after every addition of standard/DEE
Centrifuge samples 3 mins at 2000 rpm
Remove top layer into clean labelled glass screwtop tube using glass pipette
Evaporate to dryness under nitrogen at 40° C. (also used RVC to evaporate, 40° C., 100 mbar, 25 mins)
Reconsititute in 100 ul mobile phase. Allow to stand for 30 mins and then vortex 3 mins
Transfer to HPLC vial with insert
Mobile Phase Preparation
Materials
[0080] Potassium phosphate monobasic, SAFC lot 1370660
NaOH: Sigma Aldrich, reagent grade beads, 97% Bx 01209BH
Acetonitrile: Fisher HPLC gradeBx 1095614
20 mM potassium phosphate buffer prepared with Q3 water, adjusted to pH 6 with NaOH
Buchner filtered through 0.2 um 47 mm nylon membrane
Chromatographic Conditions
[0081] Gynkotek HPLC system with Perkin Elmer LS 40 fluorescence detector
Column: phenomenex Lichrospher RP-18 100A 125×4.00 mm 5 micron with guard column
Detection: excitation: 251 nm emission: 289
Gradient: starting conditions 60% buffer 40% acetonitrile flowrate 1 mL/min
Increase from 40-80% acetonitrile over 10 mins, hold at 80% for 4 mins
Return to starting conditions for 2 mins prior to next injection
Injection volume 20 uL
Spiked Standard Range
[0082] 1-150 ng/mL plasma
Clinical Trial Protocol—Zolpidem 10 mg delayed-release (2 hour time-delay)
Clinical studies were carried out in Healthy male volunteers aged between 18-65 years inclusive with a body mass index (BMI) between 18.0 and 29.9 kg/m 2 .
Gastrointestinal transit of the delayed-release tablets was characterised by inclusion of a radiolabel marker, technetium-99m ( 99m Tc), complexed with diethylenetriaminepentaacetic acid (DTPA) which prevents absorption from the gastrointestinal tract. The radiolabel is incorporated into the core tablet. Each tablet was radiolabelled with 4 MBq 99 mTc-DTPA and administered with 240 ml of water at bedtime.
Subjects received a standard dinner comprising roast chicken with salad, low fat yoghurt and one cup of decaffeinated tea, coffee or juice 4 hours prior to dosing.
Scintigraphic imaging was performed using a Siemens E-Cam gamma camera fitted with a low-energy high-resolution collimator. Subjects were imaged in a standing position except during periods of sleep where the subjects were imaged lying down.
The following imaging schedule was used:
Anterior static acquisitions of 25-second duration each were collected immediately after dosing then every 15 minutes until complete release of radiolabel marker.
A 5 mL pre-dose blood sample was taken from each subject 15 minutes before dosing. Following dosing blood samples were taken according to the following schedule:
Every 15 minutes until burst release observed by scintigraphy then every 15 minutes for 2 hours then every 30 minutes for 1 hour then hourly until end of study day (9 hours post-dose). See FIG. 5 .
Blood samples were centrifuged at 2000 g for 10 minutes and the plasma fraction removed and stored at −20° C. for subsequent analysis. See FIG. 6 .
FIG. 7 shows the release profile of a tablet formulation comprising a delayed release layer of 50/50 w/w glycerol behenate/LH32 demonstrating the ability to vary the period of delay before pulsed drug release. | In one aspect, the present invention is concerned with a treatment where it is desired that an active agent is designed to be released in a pulse at a time point some time after administration of the active agent. The present invention is particularly suited to administering an agent which may be released whilst a subject is sleeping. As well as treating certain conditions by a particular regime, the invention also provides novel formulations for a delayed, followed by a pulsed release of drug. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an asynchronous transfer mode (ATM) network switch. More particularly, this invention relates to improvements in the buffering of the flow of cells through an ATM network switch.
2. State of the Art
In an ATM switch of the cross-point type, it is known in the art to provide a buffer in the form of FIFO between each input port or slot controller and the switch fabric. Each FIFO provides a fullness level signal to indicate whether or not the FIFO is full. These level signals are ORed, so that, if any of the FIFOs is full, no data is sent from the slot controllers to the switch fabric. The result of such an arrangement is that the flow rate of the cells is limited where any one data path is blocked.
As an improvement to the standard buffering system of the art, it has been proposed in UK Patent Application GB 2272820A to Fischer et al. to provide each input port server with a plurality of buffer stores corresponding to the plurality of output port servers at the output of the switch. While such an arrangement is somewhat effective in freeing the flow of data through the switch when one particular data path is blocked, the arrangement does not actively or effectively manage the flow of data through the switch in congested situations.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide an ATM network switch with improved data flow characteristics.
It is another object of the invention to provide an ATM network switch with data buffers for each class of data traffic being handled.
It is a further object of the invention to provide an ATM network switch with input buffers where congestion is handled, and data flow is improved by providing a feedback signal from the switch fabric to the input buffers.
In accord with the objects of the invention, an ATM network switch is provided and broadly includes a switch fabric, and a plurality of slot controllers, each having at least one input port coupled to the switch fabric. The switch fabric comprises means for switching a data cell input on any one port to a selected one or more of the other ports thereto. The slot controllers comprise cell receiving means for receiving ATM cells from a least one external data link, cell transmitting means for transmitting ATM cells outwardly on each external data link, a plurality of cell buffer means with at least one buffer means for each other slot controller in the switch, and buffer control means for controlling the passing of cells from the buffer means to the input port to the switch fabric. The buffer control means is coupled to signalling means in the switch fabric for signalling back to the buffer control means in each slot controller an indication of the congestion level of each switching path through the switch fabric from one port thereto to another. In this manner, the buffer control means controls the output of cells from the buffer means in accordance with the congestion levels signalled.
Preferably, the switch fabric comprises a plurality of switching elements. Each switch element is arranged to receive copies of all cells input to the switch, to read a switch fabric header code added to the cell by the receiving slot controller, and to pass only those cells whose code is correct for the particular element. The switching elements are suitably in the form of ASICs, and each may be provided with an input buffer in the form of a FIFO, suitably of 4-cell capacity, for each input to the ASIC from the slot controllers. The FIFOs are preferably of the type providing a FIFO fullness (level) signal indicating the number of cells contained therein. This may thus be a two-bit signal, and these two-bit signals are output to the appropriate slot as thirty-two serial bits (for a 16×16 port switch), representing the status of all the FIFOs in the switch fabric for the particular input slot. The FIFO level signals are preferably used as an input to arbitration logic, which is arranged to determine which is the next cell to be sent to the switch fabric from the slot controller.
Preferably, the arbitration logic comprises a separate cell finder for each priority level (e.g., four cell finders for four cell priority levels). The cell finders are preferably arranged to look at the state of the FIFOs comprising the slot controller's buffer means in a sequential fashion to find the next cell at its own priority level ready to be sent to the switch fabric. The cells are sent according to priority level. However, in accord with a preferred aspect of the invention, timer means ensure that, even if there are top priority cells waiting to be sent, the lower priority cells are not delayed beyond a predetermined time.
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 diagrammatic representation of a slot controller and a portion of the switch fabric of a network switch in accord with the invention.
FIG. 2 is a diagrammatic representation of a portion of the switch fabric showing the structure in more detail of the switch fabric in more detail.
FIG. 3 is a diagrammatic representation of the arbitration logic forming part of the slot controller shown in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In accord with the invention, an ATM switch comprises a switch fabric 9, and a plurality (e.g., sixteen) of slot controllers 11, of which only one is illustrated in FIG. 1 for the sake of clarity. Each slot controller 11 has at least one external data link 12, and connections to an input port 13 and an output port (not shown) of the switch fabric 9. The switch fabric 9 comprises a plurality (e.g., sixteen) switching elements 14, of which only two are illustrated in FIG. 1, again for the sake of clarity. It will be appreciated that the switch may comprise a greater or smaller number of inputs than illustrated, and thus require more or fewer than sixteen slot controllers and switching elements. Each switching element 14 is preferably embodied in the form of an ASIC, and preferably includes a 4-cell FIFO 15 and a control device 16 for each of the input ports 13. The function of the control device 16 is to determine from a switch fabric header added to the cell by the slot controller processor means 19 (as described hereinafter) whether or not the cell should be written to the associated FIFO 15 or discarded. Only those cells whose switch fabric headers identify them as intended for the output port with which the ASIC is associated are thus allowed to pass to that particular port. Each FIFO 15 is arranged to send a two-bit signal back via line 17 to an arbitration logic 20 in the respective slot controller 11 which indicates the fullness of (i.e., number of cells being presently stored in) the FIFO (e.g., zero, one, two, or three or four). The manner in which this is done is described hereinafter in more detail with reference to FIG. 2, while the operation of the arbitration logic is described in more detail with reference to FIG. 3.
Within each slot controller 11, additional buffering is provided by means of a plurality of sets of FIFOs 18; one set for each output port or destination on the switch fabric, and each set including a separate FIFO for each class of traffic. Thus, in the example illustrated, each set of FIFOs includes four FIFOs 18 to cover four different classes of cell traffic. In some circumstances fewer, or possibly more, classes of cell traffic may be provided, and thus the numbers of FIFOs in the set may be different. Regardless, each FIFO can hold a plurality of cells, with a single FIFO potentially holding cells from a plurality of different VCs (Virtual Connections). Each of the FIFOs in the sets 18 is arranged to send, on a serial line 10 to the arbitration logic 20, a one-bit signal to indicate whether a cell is waiting to be sent to the switch fabric. With sixteen slots and four levels of priority, sixty-four bits of information are thus generated to be sent on line 10.
The slot controller 11 comprises a processor means 19 for routing incoming cells on the external data line 12 to the appropriate FIFO according to destination and priority, as indicated by the routing information in the cell headers. "Priority 0" cells, the highest priority, will normally be sent to the switch fabric in preference to cells of lower priority, while "Priority 3" cells are of the lowest priority and will only normally be sent when there are not higher priority cells to be sent. The processor means 19 reads the destination and priority coding in the header of each incoming cell received from the external link in a manner described in more detail in co-owned UK Patent Published Application No. 2287854, which is hereby incorporated by reference herein in its entirety, and adds to the cell a switch fabric header, which indicates the destination output port from the switch fabric. The processor means 19 then routes the cell with the header to the appropriate FIFO 18 to await transmission to the switch fabric.
FIG. 2 shows diagrammatically how the levels of the FIFOs 15 are signalled back to the slot controllers. For the sake of clarity, a four slot switch fabric is illustrated, but the principles of operation are the same for a larger switch. The ASICs 14 each have a timing synchronization signal and a two-bit register (not shown) on each FIFO level line 17, each line 17a-d respectively being connected to the two-bit register for the FIFO 15 associated with the respective one of the input ports 13a-d from the four slot controllers (in this case--in the embodiment described with reference to FIGS. 1 and 3, sixteen slot controllers are provided, so that there will be four times as many components). On receipt of the synchronization pulse the registers are loaded with the two-bit level signal, and these registers together act as a shift register on each line 17. With each line 17 grounded at one end to provide a zero (0) input, the shift registers each add their two bits in serial form, resulting in an eight-bit output on each line 17a-d, representing the levels of the four FIFOs associated with the respective input port 13a-d. In the case of the sixteen-slot arrangement illustrated in FIGS. 1 and 3, a thirty-two-bit register entry for the sixteen switching elements would be shifted out to the slot controller 11.
The arbitration logic 20 within the slot controller determines the order of transmission of the cells from the FIFOs 18 to the switch fabric. As may be seen more clearly from FIG. 3, the arbitration logic 20 preferably comprises a thirty-two-bit shift register 21 which receives the thirty-two-bit level signal from the switch fabric on line 17 for the particular slot controller. Every thirty-two clock intervals of the system clock, the contents of this register 21 are loaded into a thirty-two-bit storage register 22, representing the "OLD" values. Sixteen decision logic elements 23 are each arranged to take two bits from the OLD register 22 and the corresponding two bits from the shift register 21 and to perform a comparison. As a result of the comparison, the decision logic elements 23 output a "1" or a "0", indicating OK or NOT-OK for the ability of the particular buffer 15 to receive another cell. The decision logic elements carry out a process which looks at the direction of change in the FIFOs 15, since pipelining in the system means that the data is already out of date when it arrives at the logic 20. The logic elements 23 each generate a respective Cell Available (OK/NOT-OK) flag for each FIFO 15 according to predetermined rules. For example, if the count is zero or one, and OK-to-send flag is generated; and if the count is two and was previously three, an OK flag is again generated. However, if the count has remained at two, has gone from one to two, or is at three, then a "Not-OK" flag is generated. Each of these sixteen flags is stored in a respective single-bit storage register 24. As each new string comes in, the comparison is carried out so as to generate the new set of flags, as described, and then the new values are stored. The flags are supplied to a rotating priority arbiter logic 25, whose operation is described hereinafter.
The sixty-four bits indicating the status of the FIFOs 18 arrive on line 10 and are stored in RAM 26, before being processed by priority logic 27, which looks at the signals representing one slot (four priorities) in turn and outputs a three-bit signal made up of two bits representing the highest priority level present in four FIFOs of the set 18, and one bit as a valid signal which is set to "1" if all the FIFOs in the set are not empty (and "0" if all the FIFOs in the set are empty). The logic element 27 thus receives sixty-four bits and outputs a three-bit signal on each of sixteen lines 28 to the priority arbiter logic 25.
The priority arbiter logic 25 is arranged to process each of the slots in turn, shifting the start point by one slot each processing cycle; a rotate signal input on line 29, from a simple four-bit counter (not shown) being used to cause the shift. The shifting is provided to ensure that the arbitration process does not result in any one slot being "favored" over the other slots, with its FIFOs being selected more frequently. The logic 25 looks at the sixteen three-bit inputs on the lines 28 and selects those in which the third bit is "1", indicating a cell present in the respective FIFO set 18. The logic then looks at all of the three-bit signals which show "level 3" priority as being the highest available priority, performs a logical AND process with the OK/NOT-OK values, and outputs a 4-bit signal representing the identifying number of the first FIFO set 18 found for which the relevant FIFOs 15 in the switch fabric have signalled availability to receive cells. This signal is stored in a holding register 30, along with two bits identifying the priority within the set to be sent. Before this value is used, however, the process is repeated for each successively higher level or priority, and if an output is present, it overwrites the four-bit value in the register 30. Thus, the highest available priority is the one which remains in the register 30 to signal the output of the cell. A request signal is also generated by the logic 25 as a logical OR of the outputs, indicating that all the priorities have been examined and the request can be sent back on line 10 to release a cell to the switch fabric input port.
Three timers 31a, 31b, and 31c, one for each of the cell finders for priorities "1", "2", and "3", also provide one-bit inputs to the logic 25, to indicate a time-out for a particular priority level. "Priority 0" does not require a timer, as the priority level does not permit delay. The logic 25 causes "priority 0" cells to be transmitted first, but if the flow of these cells is such that no lower priority cells would be transmitted, the timers come into play causing transmission of the lower priority cell according to a predetermined timeout period for that level of priority. If, for example, a time-out signal is received for "priority 3", the order of processing the priorities is changed so that "priority 3" is processed last, rather than "priority 0", and is thus the operative code remaining in the register 30 at the end of the cycle.
The arrangement described can readily function with a dual switch fabric as described and claimed in co-owned application GB9607539.5, which is hereby incorporated by reference herein. Separate logic would be used for each switch fabric, and all the components described would be duplicated except for the priority timers and the logic 25, but this would generate an arbitration request and receive the grant back, as described in that application, before causing the cell to be sent.
There has been described and illustrated herein an ATM switch with a switch fabric and a plurality of slot controllers, where the slot controllers include buffer and arbitration means, and the switch fabric includes feedback means to the arbitration means of the slot controllers for providing information which is used by the arbitration means to decide which cells to send to the switch fabric. While preferred 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 specifications be read likewise. Thus, while the invention has been described with particular reference to a switch having a particular architecture with "slot controllers" and "switch fabric elements", it will be appreciated that the concepts of the invention may be applied to other switches where a plurality of processing means are provided for forwarding incoming ATM cells to a switch fabric. Likewise, while the particular switch described is provided with sixteen slot controllers, it will be appreciated that the invention applies to switches of different sizes. Further, while particular algorithms and arrangements for the arbitration logic have been provided, it will be appreciated that other arbitration schemes could be used. 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 ATM network switch is provided with a switch fabric linking a plurality of slot controllers. Each slot controller receives ATM cells from an external data link and has at least one input port to the switch fabric. The switch fabric switches a data cell received from any one port to one or more other ports. Each slot controller is provided with a separate group of buffers for each slot controller in the switch, and stores ATM cells intended for those other slot controller in the buffers. Each group of buffers includes a separate buffer for each class of cell traffic, so that the ATM cells are stored by intended slot controller and by class. The slot controller also includes a buffer control circuit which controls the passing of cells from the buffer to the switch fabric. The switch fabric includes input FIFOs, an indication of the fullness of which is measured and signaled back to the buffer control circuit. In response to the feedback signal which is an indication of the congestion level of each switching path through the switch fabric from one port thereto to another, the buffer control circuit controls the output of cells from the slot controller buffers to the switch. | 7 |
FIELD OF THE INVENTION
[0001] The present invention is directed to a composition for oral administration to the throat to relieve snoring or other irritations of the throat, by spraying or otherwise applying the composition into the back of the throat at bedtime. The composition is preferably drug-free.
BACKGROUND
[0002] Snoring is a pernicious problem, especially for those with a regular bed partner. The noise is disruptive to sleep for both the snorer and partner, and can impair their daytime activities through sleepiness and cause relationship difficulties between them. In addition, the snorer may encounter unpleasant side effects such as dry mouth and a sore throat. Snoring is a two-part phenomenon: first, a problem such as nasal congestion causes restricted airflow through the nasal passages, leading to breathing through the mouth. Second, the turbulent flow of air through the oral passage causes vibration of the soft tissue of the palate and throat.
[0003] Current methods for treating snoring by orally administering a composition involve the use of drugs or herbal preparations, either over the counter or by prescription. As used herein, the term “drug” or the term “pharmaceutical” refers to any compound or ingredient that is intended to achieve its efficacy by absorption or ingestion into the body and that acts by metabolism or systemic means.
[0004] Descriptions of compositions for treating snoring can be found in U.S. Pat. Nos. 6,187,318; 4,668,513; and 4,556,557.
[0005] While there are several ways to address some of the problems that cause snoring, there continues to be need for a composition and method for eliminating the tissue vibration which would relieve snoring, and preferably a composition that is drug-free and free of homeopathic ingredients. This gives the user greater flexibility in using the composition of the present invention along with other treatments for treating other symptoms, such as a nasal decongestant.
[0006] The present invention is directed to reducing or eliminating the vibration of the soft tissue of the upper palate. As described previously, snoring is caused by air-turbulence induced vibrations of the soft tissue at the very back of the upper palate, which forms the beginning of the throat opening.
[0007] The present invention is based on four approaches to eliminating the soft tissue vibrations via a throat spray. First, the tissue surfaces can be firmed up using tissue-firming agents, such as an astringent. Second, the tissues can be lubricated to reduce friction-induced resonance with the turbulent airflow across them. Third, the tissues can be soothed to reduce any swelling or irritation resulting from vibration. Fourth, obstructive congesting material, such as mucous, can be thinned so that it drains from the throat, reducing turbulent flow over the obstruction and improving airflow in general. The present invention preferably encompasses all four approaches simultaneously in a single composition, but also includes the use of any of the four approaches independently or in combination with one or more of the other approaches.
[0008] The composition of the present invention may be used to treat snoring via the following method. Prior to sleeping, the composition is applied to the soft tissues of the back of the mouth and the throat, in particular to the soft palate at the rear of the mouth, to the uvula, the back of the tongue and the upper part of the pharynx. The composition is preferably applied by spray to coat those tissues, after which the user goes to sleep without disturbing the coating by eating, drinking or smoking.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to an orally administered composition for treating snoring, comprising a tissue-firming agent, a tissue-soothing agent, a tissue lubricant, and a mucous-thinning agent or an expectorant.
[0010] The present invention also includes a method for treating oral tissue to reduce or eliminate snoring, comprising the steps of firming a surface of the oral tissue; soothing the tissue; lubricating the tissue; and thinning obstructive material proximate to the tissue.
DETAILED DESCRIPTION
[0011] The orally-administered composition of the present invention generally comprises: a tissue-firming agent in an amount ranging from between about 2.0 wt-% to about 15 wt-%; a tissue-soothing agent in an amount ranging from between about 0.1 wt-% to about 15 wt-%; a tissue lubricant in an amount ranging from between about 1.0 wt-% to about 15 wt-%; and a thinning agent in an amount ranging from between about 0.1 wt-% to about 15 wt-%. The balance of the composition is made up of an inert medium, such as water or deionized water. As used herein, the expression “wt-%” refers to weight percent, unless otherwise indicated. All the ingredients of the composition should be safe for user consumption, as the composition is preferably applied to the throat and will be absorbed by the oral tissue and swallowed by the user to some extent.
[0012] The tissue-firming agent or component useful in the present invention can be any agent that can tighten or constrict body tissues. Preferably, the tissue-firming agent is an astringent or similar compound. If an astringent is used, it is preferably selected from the group comprising alcohol, witch hazel, aluminum potassium sulfate, aluminum sodium sulfate, aluminum sulfate, zinc chloride, acacia tea, tannins, tincture of myrrh, and a combination thereof.
[0013] The tissue-soothing agent or component useful in the present invention can be any agent that can reduce irritation or inflammation of body tissues. Examples of tissue-soothing agents include, but are not limited to, essential oils, glycerin, camomile (chamomile) flowers, alpha bisabolol (an extract derived from camomile flowers), and a combination thereof.
[0014] As used herein, the term “essential oils” describes a blend of natural fragrance oils including wintergreen oil, menthol, peppermint oil, anise oil and clove oil. In addition to the essential oils mentioned herein, there are numerous other oils that would be useful in the present composition. In particular, eucalyptus, spearmint, pine, chamomile, lemon and orange oils may be useful in the composition of the present invention. In addition to, or as an alternative to using the natural essential oils of this composition, purified or synthetic versions of the essential components may be used in place of the naturally occurring oils in the present invention.
[0015] The tissue lubricant component useful in the present invention is any agent which provides moisture to body tissues, such as a humectant or a similar compound. Preferred humectants include glycerin, sorbitol, inulin, high fructose corn syrup, sucrose, phosphocholinamin, sodium alginate, and a combination thereof.
[0016] The mucous-thinning or expectorant component useful in the present invention includes any agent which thins thickened mucous and causes it to drain through nasopharyngeal passages. Preferred expectorants include essential oils, alcohol, elecampane, cayenne, cineole, and a combination thereof.
[0017] As can be seen from the foregoing, there are many ingredients available that serve more than one function in the composition of the present invention, and as described previously, the composition of the present invention may include one or more of the aforementioned components. In a particularly preferred embodiment of the present invention, the composition includes each of the four components. However, the composition is useful with just the tissue-firming component, but preferably also includes a tissue-soothing component, and more preferably also includes a tissue lubricant.
[0018] Table I shows the ranges of ingredients in one embodiment of the present invention.
[0000]
TABLE I
Ingredient
Function
High
Preferred
Low
Water
Medium
50%
86.0%
96%
Alcohol
Astringent, Thinning
15%
7.5%
2.0%
Glycerin
Soothing, Lubricant
15%
4.0%
1.0%
Essential Oils
Soothing, Decongesting,
10%
0.5%
0.1%
Thinning
Other
Stabilizers, Preservatives, etc.
10%
2.0%
0%
[0019] The essential oils useful in this invention and described in the embodiment of Table I consist primarily of a blend of menthol and wintergreen oil, preferably in approximately equal amounts, but within weight ratios of 10:1 to 1:10. Secondarily, the blend also contains peppermint oil, anise oil, and clove oil. Wintergreen and menthol preferably constitute the bulk of the blend, with each in the range of 33% to 49% of the total weight of the essential oils, with the peppermint, anise, and clove in approximately equal amounts and comprising 2% to 34% of the total weight of the essential oil blend.
[0020] In one embodiment, a bioadhesive agent is included in the composition of the present invention. The bioadhesive causes the composition to adhere to the throat tissues, and may prolong the desired effects of alleviating snoring or other throat irritations. Examples of bioadhesive agents include hydroxypropyl cellulose and carbopol.
[0021] Other ingredients, such as flavor-, appearance- or fragrance-enhancing agents, may be used as long as they do not interfere with the operation of the composition on the oral tissues. In some cases, such as with the essential oils, the components of the composition may be selected to impart a desirable flavor or fragrance to the composition. Other ingredients, such as preservatives, emulsifiers, stabilizers, and the like may be included in the composition of the present invention to enhance shelf life or use of the composition.
[0022] The composition of the present invention can be made using any conventional means to blend the components together. One preferred embodiment of the method is used to ensure that a homogeneous solution results from the blending process. Glycerin, flavorings, if any, and preservatives, if any, are added to water and blended. The essential oil and solubilizer or emulsifier, if any, are separately blended. The essential oil blend is combined with ethanol and mixed, and then blended with the glycerin-containing blend. More preferably, the final mixture is blended for an extended period of time, such as about 30 minutes, to ensure homogeneity and alcohol denaturation, if needed.
EXAMPLE I
[0023] A clinical study was conducted with 50 patients who were self-described “nightly snorers”, were over 18 years of age, were not currently being treated for snoring, did not fit a profile for sleep apnea, and had a regular bedpartner. Daily diaries of snoring and snoring related problems were kept by both the snorer and the bedpartner. Each patient first completed the diary for a week with no treatment as a baseline, and then used each of three products in random order on subsequent weeks. The three products were all oral sprays used at bedtime per label directions. Data from the first twelve patients to complete the study were used for the analysis below.
[0024] The embodiment of the present invention tested in the clinical study had the following approximate formulation.
[0000]
TABLE II
Example I Formula
Ingredient
Function
Level
Water
Medium
88.14%
Alcohol
Astringent, Thinning Agent
6.90%
Glycerin
Soothing, Lubricant
3.90%
Polysorbate 80
Solubilizer
0.05%
Sodium Saccharin
Sweetener
0.03%
Cetylpyridinium Chloride
Preservative
0.025%
Domiphen Bromide
Preservative
0.005%
Flavor Oil
Soothing, Decongestant
0.15%
[0025] The flavor oil included methylsalicylate, menthol, peppermint oil, eugenol, anethol, and a propylene glycol/alcohol carrier, and was obtained from Ungerer & Company, Lincoln Park, N.J. Eugenol is the essential component of clove oil, menthol is crystallized from mentha oil, anethol is the essential component of anise oil, and methylsalicylate is the essential component of wintergreen oil.
[0026] Two other products were compared with the composition of the present invention. Product A (SnoreStop®, a product of Green Pharmaceuticals) is homeopathic and lists the following ingredients on the label: purified water, alcohol, glycerine, fructose, flavor, Nux vomica 4×, Belladonna 6×, Ephedra vulgaris 6×, Hydrastis canadensis 6×, Kali bichromicum 6×, Teucrium marum 6×, Histaminum hydrochloricum 12×.
[0027] Product B (SnoreFIX™, a product of SnoreFIX Inc.), lists the following ingredients on the label: purified water, glycerin, oat beta glucan, lecithin, DL-alphatocopheryl acetate, retinyl palmitate, ascorbic acid, linoleic acid, pyridoxine HCl, licorice extract, slippery elm extract, prickly ash extract, sweet almond oil, hybrid sunflower oil, polysorbate 20/80, eucalyptus oil, lemon oil, peppermint oil, benzyl alcohol, potassium sorbate, disodium EDTA.
[0028] An analysis of the results of the clinical study on snoring showed the following unexpected results.
Asked of the Snorer's Bedpartner:
[0029] 1. Describe your partner's snoring loudness: none, low, moderate, loud, very loud?
[0000]
Mean
Worst
No Treatment
3.42
Product A
3.09
Product B
2.48
Best
Current Invention
2.30
[0030] 2. Over how much of the night did your partner snore: none, some, half, most, all?
[0000]
Mean
Worst
No Treatment
3.10
Product A
2.74
Product B
2.42
Best
Current Invention
2.14
[0031] 3. How effective was the product in reducing your partner's snoring: extremely, very, somewhat, slightly, not at all?
[0000]
Mean
Worst
No Treatment
—
Product A
3.90
Product B
3.05
Best
Current Invention
2.77
Asked of the Snorer:
[0032] 4. On awakening, was your mouth dry: no, a little, a lot?
[0000]
Mean
Worst
Product A
1.79
Product B
1.75
No Treatment
1.65
Best
Current Invention
1.60
[0033] 5. On awakening, was your throat sore: no, a little, a lot?
[0000]
Mean
Worst
Product A
1.34
Product B
1.30
No Treatment
1.27
Best
Current Invention
1.23
[0034] 6. Describe the quality of your sleep last night: excellent, good, fair, poor?
[0000]
Mean
Worst
No Treatment
2.27
Product A
2.04
Product B
1.97
Best
Current Invention
1.84
[0035] The composition of the present invention clearly performed better than the other commercial products, and was effective at reducing snoring and snoring related symptoms.
EXAMPLE 2
[0036] A clinical study was conducted to evaluate the efficacy of the throat spray composition of the present invention concurrently used with a Breathe Right® nasal strip which is designed to alleviate snoring and is available from CNS, Inc., Minneapolis, Minn. The study was conducted with one hundred and sixty-one (161) adult subjects. Males (90) and females (71), ranging in age from 21 to 70 years, who qualified, were recruited for this study. Recruitment was done using newspaper advertising and walk-ins to the research center. One hundred and fifty two (152) subjects completed this study. The subjects were required to be frequent snorers as reported by their bedpartners, to have a consistent bedpartner, and to not have a history or previous diagnosis of sleep apnea.
Study Design:
[0037] One week prior to the start of this study, all subjects were instructed to refrain from the use of similar products and not to introduce any new oral or nasal products for the duration of the test. Subjects and their bedpartners were asked to complete a questionnaire as a baseline of their untreated snoring. Subjects were then randomly assigned to be given a nasal strip or throat spray to use for one week. Subjects and their bedpartners were asked to complete daily questionnaires on their snoring properties during the test period.
[0038] At the end of the first week, questionnaires and unused product were collected and both products were dispensed to the combined group for a week-long test period. Again, subjects and their bedpartners were asked to complete daily questionnaires of their snoring.
[0039] The embodiment of the present invention tested in this clinical study had the following approximate formulation.
[0000]
TABLE III
Example 2 Formula
Level (weight
Ingredient
Function
percent ± 0.01%)
Deionized Water
Medium
87.69
Glycerin
Soothing, Humectant
4.00
Sodium saccharin
Sweetener
0.06
Cetylpyridinium chloride
Antimicrobial
0.05
Ethanol
Astringent, Expectorant
7.85
Polysorbate 80
Solubilizer
0.10
Flavor oils
Soothing, Expectorant
0.25
[0040] The flavor oil blend used in this formula included wintergreen, menthol, peppermint, anise, and clove oils.
Results:
[0000]
The throat spray composition of the present invention is effective at reducing snoring at a statistically significant level.
Breathe Right® nasal strips are effective at reducing snoring at a statistically significant level.
The combination of nasal strips and throat spray is effective at reducing snoring at a statistically significant level.
88% of the snorers and 95% of their bedpartners considered the nasal strips effective for snoring
85% of the snorers and 95% of their bedpartners considered the throat spray effective for snoring
89% of the snorers and 97% of their bedpartners considered the combination of the two products to be effective for snoring
[0047] While the preferred application, and the one used in the clinical studies, is to spray the product onto the throat at bedtime, the formula could also be applied with a swab or other similar device, by swishing, rinsing or gargling, or from a nebulizer or humidifier. The product could also be applied during the night or any time while sleeping to prevent snoring.
[0048] While the throat spray composition tested in the clinical studies was a thin, clear liquid, there may be advantages to delivering the composition in another format, so it is retained longer on the throat. Any delivery form which permits the active ingredients to be applied onto the throat tissues is contemplated. Examples of suitable alternate delivery forms include providing the active ingredients in a lozenge or wafer, or as an edible film made with a water soluble cellulose matrix.
[0049] While not intending to be bound by theory, it is believed that the composition of the present invention relieves snoring by delaying or eliminating the onset of tissue trauma or irritation while the subject is sleeping. As such, although the product is intended to relieve snoring, the mechanism of action is generally applicable to relieve congestion and irritation of tissues, even if snoring is not present.
[0050] Although the foregoing describes many preferred embodiments of the composition and methods of use of the present invention, it is not intended to limit the true scope of the invention, which is defined by the following claims. | An orally administered composition for relieving or eliminating snoring is described. The composition generally has four mechanisms of action for combating snoring. The composition includes a tissue-firming or astringent agent to firm up throat tissue. The composition also includes a soothing agent to soothe irritated or inflamed tissues. Also included in the composition is a lubricant to moisten dry or dehydrated tissues, and a mucous-thinning or expectorant agent to help remove any obstructive matter near the throat tissues. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates, in general, to three state gates and more particularly to a non-inverting, glitchless three state gate that does not supply current to an input bus.
2. Background Art
Three state gates have an output which is capable of assuming an active high, an active low, or a high impedance state. Previously known non-inverting, three state gates typically comprise a push-pull output driver stage, a phase splitting stage, and an input stage as illustrated in FIG. 1 which will be discussed in detail hereinafter in the Detailed Description of the Invention. The push-pull output driver stage comprises a dual transistor arrangement wherein an upper transistor is coupled between a DC voltage supply and an output load and a lower transistor is coupled between the output load and ground. In operation a high output voltage is realized at the output terminal by turning on the upper transistor and turning off the lower transistor; a low output voltage is realized by turning off the upper transistor and turning on the lower transistor; and a high impedance is achieved by turning off both transistors.
The phase splitting stage comprises a transistor coupled between the bases of the two transistors of the output stage that would selectively turn on one of the two output stage transistors. The input stage comprises a PNP transistor having a base connected to an input terminal. A first NPN transistor has its base connected to the emitter of the PNP transistor. A second NPN transistor has a base connected to the emitter of the first NPN transistor. The bases of the first NPN transistor, the second NPN transistor, the phase splitting transistor, and the output stage upper transistor are each coupled to an output enable terminal by a diode. A low output enable signal directs current away from the transistor bases through these diodes, thus turning off both of the upper and lower transistors of the output stage, giving a high impedance at the output terminal. A high signal on the output enable terminal reverse biases the diodes, effectively removing their paths from the circuit.
However, when switching from the high impedance state to an active high, this previously known arrangement would have a glitch in the output, wherein the output would tend to go to an active low from the high impedance state prior to going to the active high. This glitch could be avoided by removing the diode coupled between the base of the first NPN transistor (the emitter of the PNP transistor) and the output enable terminal. However, by removing this diode, problems are created in a bus oriented system. Current would then flow to the input bus from the PNP transistor.
Thus, a need exists for an improved non-inverting three state gate having a smooth, glitchless transition from a high impedance state to an active high while preventing current from flowing to the input terminal.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an improved non-inverting three state gate.
Another object of the present invention is to provide a glitchless, non-inverting three state gate that does not supply current to the input terminal.
In carrying out the above and other objects of the invention in one form, there is provided an improved three state gate capable of assuming a first state, a second state, or a high impedance state at an output. The gate is adapted to receive first and second input signals which are each capable of assuming first or second voltage levels. An output means includes a first output transistor for supplying current to the output load when the first input signal has assumed the first voltage level and the second input signal has assumed the first voltage level, and a second output transistor for sinking current from the output load when the first input signal has assumed the second voltage level and the second input signal has assumed the first voltage level. The first output transistor will not supply current to the output load and the second output transistor will not sink current from the output load when the second input signal assumes the second voltage level. A logic means is coupled to the output means and is responsive to the first and second input signals. A level setting means is coupled to the logic means for substantially preventing glitches in the output when the first input signal has assumed the first voltage level and when the second input signal assumes the first voltage level.
The above and other objects, features, and advantages of the present invention will be better understood from the following detailed description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates in schematic form a prior art three state gate;
FIG. 2 illustrates a wave-form of the output of the prior art circuit of FIG. 1 when the output is switched from the high impedance state to an active high state; and
FIG. 3 illustrates in schematic form the preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a prior art circuit illustrative of the problem of eliminating the glitch occuring during the high impedance state to digital high state transition while preventing current from flowing to the input terminal. The prior art circuit includes an input stage 10, a phase splitting stage 11, and a push-pull output driver stage 12.
The input stage 10 comprises PNP transistor 13 having a base connected to input terminal 14 and is responsive to an input signal which may assume a first or second voltage level. Transistor 13 has its collector connected to supply voltage terminal 16 and an emitter coupled to supply voltage terminal 17 by resistor 18. The emitter of transistor 13 is further connected to the base of NPN transistor 19 and to the anode of Schottky diode 21. Transistor 19 has its collector coupled to supply voltage terminal 17 by resistor 22 and its emitter connected to the anodes of Schottky diodes 23, 24 and the base of NPN transistor 26. Transistors 13, 19 and diode 23 translate the voltage level of the input signal at input terminal 14 to the base of transistor 26 while providing isolation from input terminal 14. Diode 27 has its anode connected to the emitter of transistor 26 and its cathode connected to supply voltage terminal 16. The collector of transistor 26 is connected to the anode of diode 28 and the base of phase splitting NPN transistor 29 and is coupled to supply voltage terminal 17 by resistor 25.
The collector of transistor 29 is connected to the anode of Schottky diode 31, the base of NPN transistor 32, and is coupled to supply voltage terminal 17 by resistor 38. The cathodes of Schottky diodes 21, 24, 28, 31 are connected to output enable terminal 30 for sinking current from the bases of transistors 19, 26, 29, 32, respectively, when the output enable signal has a low voltage level. The emitter of transistor 29 is coupled to the base and emitter of NPN transistor 33 by resistor 34 and resistor 36, respectively. The emitter of transistor 33 is connected to supply voltage terminal 16. Transistor 33 and resistors 34, 36 provide an active pull down for the base of transistor 42. The emitter of transistor 32 is connected to the base of NPN transistor 37 and is coupled to supply voltage terminal 16 by resistor 38. Supply voltage terminal 17 is coupled to the collectors of transistors 32, 37 by resistor 39. Output terminal 41 is connected to the emitter of transistor 37 for supplying current thereto and the collector of transistor 42 for sinking current therefrom. The emitter of transistor 42 is connected to supply voltage terminal 16.
A low voltage level applied to output enable terminal 30 will divert current through diodes 21, 24, 28, 31 from the bases of transistors 19, 26, 29, 32, respectively, insuring their nonconductivity. Since transistors 29, 32 are off, the bases of transistors 37, 42 will not receive any current. With both of transistors 37, 42 off, output terminal 41 will reflect a high impedance. However, when a high voltage level is applied to output enable terminal 30, diodes 21, 24, 28, 31 are reverse biased, effectively taking their paths out of the circuit. A high voltage level on input terminal 14 will turn off transistor 13, thereby translating a high signal to the bases of transistors 19, 26. With transistor 26 on, the base of transistor 29 goes low, turning off transistor 29 and translating a high signal to the basis of transistors 32, 37 and translating a low voltage level to the base of transistor 42. With transistor 37 on and transistor 42 off, output terminal 41 reflects an active high state.
A low voltage level on input terminal 14 will turn on transistor 13, thereby translating a low to the bases of transistors 19, 26. With transistor 26 off, the base of transistor 29 goes high, turning on transistor 29 and translating a low voltage level to the bases of transistors 32, 37 and translating a high voltage level to the base of transistor 42. With transistor 37 off and transistor 42 on, output terminal 41 reflects an active low state.
FIG. 2 illustrates the voltage characteristics of the output signal at output terminal 41 as the state of the circuit switches from a high impedance to an active high. The high impedance state is represented by waveform portion 46 and the active high is represented by waveform portion 47. A glitch 48 occurs as the output signal switches from the high impedance state 46 to the active high state 47. This glitch 48 is caused by the inherent characteristics of the circuit of FIG. 1. When a low voltage level is applied to output enable terminal 30, the bases of transistors 29, 32 are both pulled low, turning off transistors 29, 32, 37, 42. When input terminal 14 is receiving a high voltage level and output enable terminal 30 receives a high voltage level, transistor 29 will initially turn on since the drop across transistors 29, 42 and diode 28 is only about one and a half volts. As output enable terminal 30 approaches a high voltage level, transistors 19, 26 will turn on since the voltage drop across transistors 19, 26 and diode 27 is about 2.25 volts. Transistor 29 would then turn off since its base current is diverted through the collector of transistor 26.
Referring now to FIG. 3, there is shown a circuit illustrating a preferred embodiment of the present invention. The circuit of FIG. 3 is similar to the prior art circuit of FIG. 1, having similar devices identified with identical numbers for ease of description. The circuit of FIG. 3 includes four additional devices including NPN transistor 51, resistor 52, and diodes 53, 54. Transistor 51 has its base connected to the collector of transistor 19 and to the anode of diode 53. The cathode of diode 53 is connected to output enable terminal 30. Transistor 51 has its collector coupled to supply voltage terminal 17 by resistor 52 and its emitter connected to the anode of diode 54. The cathode of diode 54 is connected to the base of transistor 29 and the collector of transistor 26. In another embodiment, not shown, a diode can be substituted for transistor 51 wherein its cathode would be connected to the anode of diode 54 and its anode would be connected to the anode of diode 53 and coupled to supply voltage terminal 17 by resistor 52.
When the voltage level of the output enable signal is high, thereby reverse biasing diodes 21, 24, 28, 31, 53 and the voltage level of the input signal at terminal 14 is low, transistor 13 is turned on, causing the base of transistor 19 to go low. Since transistor 19 is off, the collector of transistor 19 goes high and transistor 51 is turned on, thereby supplying current to the base of transistor 29. With transistor 29 on, current is supplied to the base of transistor 42 causing output terminal 41 to reflect an active low state.
When the voltage level of the input signal at the base of transistor 13 is high, current is supplied to the base of transistor 19 and therefore to the base of transistor 26. A low is translated to the base of transistor 51 rendering it nonconductive. Since transistor 26 is conductive, no current is available for the base of transistor 29, thereby resulting in transistors 32, 37 being conductive and a high output at output terminal 41.
Diodes 21, 23, 24, 28, 31, 53 are Schottky diodes while diodes 27, 54 are PN junction diodes. The type of diode was selected for the purpose of adjusting the threshold of the current path therefor. It is understood that Schottky diodes and PN junction diodes may be interchanged as long as the threshold relationship of the two current paths discussed below are maintained. The current path including transistor 51, diode 54, transistor 29, and transistor 42 must have a larger threshold than the current path including transistor 19, transistor 26, and diode 27. As the voltage level of the output enable signal initially begins to go high, this threshold differential insures that transistors 19, 26 turn on before transistor 29, with transistor 26 sinking current from the base of transistor 29 thereby maintaining transistor 29 nonconductive. Furthermore, additional diodes may be added in series with diode 54 to adjust the threshold of the current path.
By now it should be appreciated that there has been provided a gitchless, non-inverting three state gate that does not supply current to an input bus. | A three state gate having an output capable of assuming an active high, an active low, or a high impedance state is disclosed that eliminates a glitch in the output during the transition from the high impedance state to an active high. An output means includes a first transistor for supplying current to the output and a second transistor for draining current from the output. A phase splitting means determines the conductivity of the first and second transistors. A logic means is responsive to both an input signal and an output enable signal and is coupled to the phase splitting means. The logic means includes a level setting means that insures that the second transistor is not conductive during the transition of the output from the active high to the high impedance state. | 7 |
FIELD OF THE INVENTION
The present invention relates to a method for converting thermal images, namely infrared images, into visible images, and a device for carrying out the method.
BACKGROUND OF THE INVENTION
It is well known that any body whose temperature is greater than absolute zero emits radiation in the infrared range the spectral intensity of which depends on the nature of the emitting surface and the absolute temperature of the body. In many military, medical and industrial uses it is desirable to convert infrared radiation into visible light in order to observe bodies and measure their surface temperatures.
There are systems in which the infrared radiation is converted into visible light by means of image amplifiers. However, these systems only use a small part of the infrared spectrum, i.e. near visible light, in the range between 0.8 μm and 1.4 μm. As for bodies at ambient temperature the greater part of their emitted infrared energy is lost since it is located near 10 μm and cannot be utilized in this manner.
Other systems employ the near and remote infrared spectrum between 1 μm and 100 μm, for example, motion-picture camera with a thermocouple, holometer or pyroelectric type thermal detecters. These instruments require about one minute to provide an image. They are therefore incapable of monitoring moving bodies.
There are instruments which monitor moving bodies at a speed close to the standards of conventional television. To achieve such results quantic receivers are employed which must be cooled with liquid helium or liquid oxygen which is a considerable constraint.
In another system which requires about 5-6 seconds to produce a visible image, a liquid is used which is locally condensed or evaporated in greater or lesser amounts depending on the intensity of incident infrared radiation. However, apart from the fact that it needs several seconds to produce an image, which is still too long to observe moving bodies, the system must be reset to observe another image which is at least a one-minute operation even in the hands of an experienced technician.
To enable the monitoring of moving bodies or events in the infrared range, there are some devices which employ a sensitive layer which vary locally in accordance with the radiation intensity. Such local variations are usually deformations of the surface of the sensitive layer. The resulting relief image is used to control a visible light which after being reflected or transmitted by the deformed surface passes through a viewing system, e.g. a Schlieren, phase contrast or holographic system.
The difficulty with such systems lies in the choice of a suitable sensitive layer. Such layers are often of low sensitivity, and/or difficult technically to produce. For example, the part of the fine solid membrane heated by the infrared radiation expands; the neighbouring regions which are not heated or differently heated oppose the expansion of the contour of the first part thereby producing a two-dimensional warping.
It has also been proposed (see French patent No. 1,452,665) an image converter in which the control layer is a thin film of a low viscosity liquid, e.g. a hydrocarbon. The sensitive layer then comprises a thin liquid film which absorbs radiation and heats up locally. There results a variation in density and convection motion is established which may be observed if the liquid contains fine particles in suspension. Under the same conditions the free surface of the liquid deforms and produces an infrared relief image located in the liquid. Finally, a sensitive layer may be formed as a semi-conductor. In this case it is not the surface which deforms but the refractive index which changes in accordance with the infrared radiation. This procedure is not very sensitive, like all those based on the thermal variations of an optical parameter of a pure body.
By way of example of a reference illustrating the prior art French patent No. 71 08 811 (publication No. 2,081,937) may be cited, which discloses an image converter in which the liquid film, which is locally deformable as a function of the intensity of the infrared radiation, is supported by a freely deformable thin membrane.
The drawback common to all image converters utilizing a sensitive layer is that the latter must be permanently regenerated when the converter is being used. It is then necessary to provide, in addition, windshield wiper type devices which spread the layer on its support. The construction and use of such converters therefore necessarily pose technical problems. The support for the sensitive layer is not sufficiently strong to support the "windshield wiper" device. Moreover, the dimensions of the layer is perforce limited by imperatives of construction and renewal of the sensitive layer.
French patent No. 72 14 212 is concerned with a method comprising converting thermal images, particularly for viewing an object emitting thermal radiation, viz. infrared radiation, by forming a thermal image, namely that of the object, on a face of an interface which is covered with at least one layer of thermal radiation absorbing material, the distribution of the temperatures in the thermal image resulting in a variation of physical parameters of the layer.
The other face of the interface, which is reflective, is illuminated with a beam of parallel light rays the optical properties of which undergo during the reflection of the interface a corresponding variation of its optical properties. In the viewing plane a viewable secondary image exhibits the last named variation. The method according to the aforesaid French patent makes use of the index gradient and variation of the thickness of the layer of thermal radiation absorbing material.
To practice such a method the reflection of the beam of parallel light rays is effected on a plane solid-solid or solid-liquid interface. The interface is for example defined by the hypotenuse face of a prism on which is deposited a solid layer such as a methacrylic ester.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method and device of the foregoing type which eliminates the above mentioned drawbacks.
An essential object of the invention is the provision of an image converter of high sensitivity, owing to the fact that the reflection or transmission of the radiation occurs at the liquid-liquid interface.
Another object of the invention is to provide an image converter having no mechanical means associated with the sensitive layer, the thin film being formed by a simple mixture of two liquids.
Still another object is an image converter in which the dimensions of the sensitive layer may be selected as large as desired, thereby permitting, in particular, monitoring bodies of great dimension.
According to the present invention there is therefore provided a method for converting thermal images, particularly with a view to viewing an object emitting electromagnetic radiation, viz. infrared radiation, in which a thermal image is formed, namely that of the object, to one side of a plane interface which is covered with at least one layer of electromagnetic radiation absorbing liquid material. The distribution of the temperatures in the thermal image then results in a variation of physical parameters of the layer. The other side of the interface which is reflective or transmissive, is illuminated by a beam of parallel light rays the optical properties of which undergo a corresponding variation during the reflecting or transmission by the plane interface. A viewable secondary image is formed in a viewing plane which exhibits the last-named variation. The method is characterized by the reflection or transmission of the beam of parallel light rays on a plane interface which is a low surface tension liquid-liquid interface obtained by mixing two partially miscible liquids at operating temperature and pressure.
The method according to the invention makes use of local deformation of the liquid-liquid interface depending on the intensity of the electromagnetic radiation, viz. infrared radiation, due to the formation of a thermal image on the interface. Indeed, the heating of the liquid-liquid system by absorption of the infrared radiation thus leading to the formation of a thermal image, creates the horizontal and vertical temperature gradients which deform the plane liquid-liquid interface. Hence a relief image is obtained. The deformation thus induced by the infrared beam focused on the surface yields an interface which acts as a spherical mirror relative to the beam of parallel light rays. The beam so modulated due to the deformation of the interface, is reflected or transmitted onto a viewing plane defined by screen or detection system which depending on the case may employ Schlieren, Schliereninterferential, phase contrast or holographic methods.
Because a deformable medium has a spatial frequency response of the band pass type, preferably a reflective grating with the thermal image is interposed thereby permitting the optimization of the response of the system of low frequencies. When the system is uniformly thermally radiated the function of the reflective grating is to create in any event temperature gradients in the electromagnetic radiation absorbing layer, therefore to detect a zero spatial frequency (the background).
The reflective grating, preferably metal, is placed in the vicinity of the free surface of the electromagnetic radiation absorbing solution. In another embodiment it is possible to place the reflective grating at the level of the liquid-liquid interface.
In a more advantageous embodiment the reflective grating is replaced with the image of a diffraction grating formed on the surface of the electromagnetic radiation absorbing solution. The infrared radiation and the image of the aforesaid diffraction grating are therefore projected simultaneously on the surface. The advantage of this method is that all the infrared radiation reaches the sensitive layer already spatially modulated, the energy used for forming the image of the grating being of much greater intensity than that of the IR radiation to be detected. The sensitivity can thus be augmented by a factor of two with respect to the aforesaid metal grating.
In a particularly preferred form of the method according to the invention the beam of parallel light rays or beam from a point source emanates from a source emitting visible light thereby permitting the conversion of the infrared image into a visible image.
According to another aspect of the invention there is provided a device for carrying out the method. The device comprises a thermal image converter comprising illuminating means providing a beam of parallel light rays or a beam emanating from a point source, a plane interface reflecting or transmitting the beam, an optical system particularly adapted for infrared radiation, and a viewing system. The interface is coated whith at least one layer of radiation absorbing liquid material on which the optical system forms a thermal image of an object emitting electromagnetic radiation. The distribution of the temperatures in the thermal image results in a variation of physical parameters of the layer. The reflected or transmitted beam then undergoes a corresponding variation of its optical properties, which variation is exhibited by the viewing system. the converter is characterized by plane interface comprising a low surface tension liquid-liquid interface obtained by mixing two liquids which are partially miscible at the temperature and pressure of used.
As aforementioned it is desirable to incorporate into the converter according to the invention a reflective grating located in the vicinity of the free surface of the thermal radiation absorbing surface or a diffraction grating the image of which is formed in the vicinity of the free surface.
A reflective grating, for example, of metal, is comprised of metal bars spaced from one another a distance equal to the width of the bars, the inter-bar spacing x of the grating being selected so that the ratio x/d is between 10 and 20 (d being the thickness of the layer of thermal radiation absorbing liquid).
In the event a diffraction grating is used the spacing between adjacent slits is equal to that of the aforesaid metal grating. The image of the diffraction grating on the free surface of the electromagnetic radiation absorbing liquid is conventionally formed with the aid of a lens and a semi-transparent glass plate disposed above the free surface.
In the description which follows the target designates the unit comprised of the liquids forming a liquid-liquid interface, it being understood it is in no way limited to a two-phase system and that the present invention may be practiced with a three-phase system.
In another particularly advantageous embodiment of the converter according to the invention a blocked target obtained in the following manner is employed.
A two-phase liquid system separated by a sharp, optically plane liquid-liquid interface is produced and the target is blocked by arranging a glass plate transparent to infrared radiation on the free surface of the thermal radiation absorbing liquid; a very sensitive and convenient to use target is thereby available owing to the fact that the target is blocked by a plate.
According to another very advantageous embodiment it is possible to use a three-phase target, that is, the reflecting or transmitting interface is covered with two layers of liquid material. The three-phased unit is then covered as above with an IR transparent plate to provide a blocked target of more convenient use.
The essential feature of the invention is the combination of two partially miscible liquids I and II producing an optically plane, low surface tension liquid-liquid interface.
To obtain this liquid-liquid interface one proceeds in the following manner: two liquids I and II are mixed which have the basic property of being partially miscible at operating temperature and pressure. Under these conditions two mutually saturated solutions A and B are obtained which yield in mechanical equilibrium a sharp optically plane surface of separation called a liquid-liquid interface I AB . When the converter according to the invention is used, the heating of the liquid-liquid system by absorption of the infrared radiation creates temperature gradients which deform the plane interface separating the two saturated solutions A and B depending on the intensity of the incident infrared radiation. The fact that the liquid-liquid interface has a low surface tension facilitates the deformation of the interface.
These two liquids I and II must be different as regards refractive index and density, and it is mandatory that they be of low viscosity. For instance, the liquid I has a viscosity between 0.5 and 100 centistokes at the operating temperature. The thermal image is formed in the saturated solution A (carried liquid) with a high concentration of liquid I.
Solution A has near-infrared absorbing properties, that is, in a spectral band between 1 and 100 microns. It is especially preferred that liquid I should absorb the infrared radiation in the 8-12 micron or 3-5 micron spectral band which are atmospheric ranges which correspond to the maximum emission of the bodies at ambient temperature.
Solution A is a thin film of low viscosity the thickness of which is between 5 and 300 microns, preferably between 5 and 200 microns, and more particularly between 5 and 100 microns. Solution A possesses a surface tension highly dependent upon the temperature. This is a necessary condition which contributes to the sensitivity of the device. The surface tension with the air is, for example, of the order of 0.02 dyne/cm °C. at 20° C. The mixture of partially miscible liquids I and II also presents another advantage: the surface tension of the interface which separates the two saturated solutions A and B may be of very low magnitude. The interfacial tension between the solutions A and B is, for example, of the order of 1 dyne/cm or less at ambient temperature. It becomes zero at the critical temperature of miscibility. Then the two-phase system disappears and a single liquid phase takes its place.
The last condition to be met to obtain a very sensitive device is that solution A have low thermal conductivity.
The invention provides an image converter of high sensitivity. The sensitivity is all the higher as the surface tension of the liquid-liquid interface is low. Indeed, it has been found that there is a direct relationship between the sensitivity and the surface tension. In practice an interface will be used having a surface tension less than 1 dyne/cm and preferably of the order of about 0.1 dyne/cm.
For liquid I are especially used substituted polysiloxanes, silicone oils, acetic acid, methanol, phenylacetic acid, butyric acid, diphenylamine, propionic acid, p-nitrochlorobenzene, acetic anhydride, acetonitrile, camphor, formic acid, cyclopentane, methylcyclopentane, cyclohexane, or methylcyclohexane, and for liquid II are used monobromonaphtalene, carbon tetrachloride, carbon sulfide, or methylene iodide.
The converter according to the invention can operate with total reflection as well as with transmission. When operating with total reflection a prism is provided under the two-liquid system, the refractive index of liquid II being greater than that of liquid I and equal or substantially equal to that of the prism. In this case, for good sensitivity, solution B has to be transparent to visible light.
When operating with transmission the only condition to be satisfied is the use of liquids I and II having very different indices.
The illuminating means of the converter according to the invention is not critical and comprises a monochromatic or polychromatic, coherent or incoherent source. Using a source of visible light then permits infrared images to be converted into visible images. The infrared optical system is a dioptric, catadioptric or catoptric lens system. The viewing system comprises a screen or a detection system employing schlieren, schlieren-interferential, phase contrast or holographic methods.
If a screen is used as the viewing system it may be arranged either in the vicinity of the liquid-liquid interface or when operating with total reflection, directly at the emergent face of the prism.
Another solution for detecting the deformation of the liquid-liquid interface consists in observing the colors associated with the deformation of the movable face of solution A when they change locally as a function of the intensity of infrared radiation striking solution A. As a variant it is also possible to make the deformation visible with normal incident, illumination.
According to a preferred embodiment there is provided a thermal image converter for viewing an object emitting infrared radiation, the converter comprising means for receiving infrared radiation emitted by the object being viewed, said means comprising an infrared radiation sensitive target, means for illuminating the infrared radiation sensitive target, means for processing and/or making visible the light rays emerging from the target, the converter being characterized in that the sensitive target comprises a first container containing two liquids partially miscible at operating temperature and pressure forming a low-surface-tension, active liquid-liquid interface, one side of the first container facing the object being transmissive of infrared radiation, a second container containing a compensating liquid-liquid interface which is substantially parallel to the active interface, whereby infrared radiation emitted by the object is focused on the less dense liquid in the first container, the means for illuminating providing a beam of parallel light rays illuminating the active interface, the angle of incidence of the rays on the active interface being chosen so as to provide substantially total reflection, rays reflected by the active interface then being reflected by the compensating interface and forming a beam of rays capable of being viewed in the means for processing and the parallel light beam illuminating the targent traversing it without any substantial change in direction irrespective of the spatial position of the converter,
In a preferred form of the foregoing embodiment the target essentially comprises two containers disposed on parallel faces of a glass rhombohedron, the first container with the active interface, a side of the first container remote from the rhombohedron and facing the object having a window transparent to infrared radiation, such as a germanium window, an inert gas such as nitrogen being contained in the free space in the first container between the liquid layer and the window, the second container essentially containing a mercury layer and a liquid whose refractive index is substantially identical with that of the glass of the rhombohedron, the last mentioned liquid being disposed between the layer of mercury and the adjacent face of the rhombohedron.
In an embodiment of this kind which comprises a rhombohedron interposed between the two containers of the target, the free faces of the rhombohedron are perpendicular to the central rays of the light beam illuminating the target. The angle of reflection of the light beam on the active interface is advantageously 60°.
Preferably the means for receiving the infrared radiation comprise, in the direction of the radiation, a lens system and a diaphragm, e.g., an iris diaphragm, for focusing the radiation on the less dense liquid contained in the first container of the target.
Preferably the means for illuminating the target comprise a collimator including a light source emitting visible light, a condenser, a diaphragm, and a lens system thereby providing a beam of parallel light rays.
Preferably the means for processing and viewing the light rays emerging from the target comprise an afocal system with two cylindrical lenses, a Porro prism, a ground glass plate, and a bi-ocular lens.
The converter according to the present invention admits of numerous applications, in military, medical and industrial fields. This device serves to render bodies visible by means of their heat radiation situated in the infrared spectrum and for measuring surface temperature gradients of the bodies.
The converter according to the invention is therefore used whenever remote temperature or radiancy distributions are to be observed.
Without attempting an exhaustive list of the possibilities of use the different fields in which the use of the converter is desirable we may cite by way of example: aeronautics and space, automobile, mechanics, metallurgy, electrolysis of metals, bonding, glass-making, paper-making, boilers and refrigeration, building, monitoring the production and distribution of electrical power, electronics, volcanology, botany, mapping ocean currents, etc.
An embodiment of the invention is described hereinafter, by way of example and in no way limiting, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 represents the combination of two liquids permitting an optically plane liquid-liquid interface to be obtained;
FIG. 2 represents the deformation of the interface in FIG. 1 under the action of infrared radiation;
FIG. 3 represents the infrared receiver operating with total reflection in the converter embodying the invention;
FIG. 4 represents the converter embodying the invention operating with total reflection;
FIGS. 5-8 represent other embodiments of the target employing the converter embodying the invention and
FIG. 9 represent the converter embodying the invention operating with normal transmission.
FIG. 10 diagrammatically represents a best mode of execution of the converter embodying the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 represents the equilibrium state resulting from the combination of two liquids I and II. Thus there is shown a two-component saturated solution B which is denser than solution A and therefore under it. The system is maintained in a container C. The concentration of one of the components I or II in each of solutions A and B only depends upon the temperature and pressure of the system. As a function of these parameters a saturated solution A may be obtained at a particular concentration and at the same time a thin liquid layer may be easily provided of uniform thickness adjustable as desired, on a liquid support without restrictions as to its spread. In addition the system is stable, i.e., when the saturated solutions are stirred they become mixed. Then the unmixing occurs quickly: under the force of gravity the solutions A and B separate to regain their starting equilibrium, that is to say, two liquid phases separated by a plane interface I AB , each of the solutions A and B having the same concentration as initially.
The plane interface I AB forms a sharp, optically plane, surface of separation.
When the two-phase system is radiated by localized infrared radiation emanating from an infrared source (not shown) and focused by an infrared optical system 0 1 deformations as represented in FIG. 2 are obtained. The infrared radiation creates, by heating, horizontal tensions on the free surface of the solution A due to the thermal variation of the surface tension of this interface. A flowing of solution A is established to balance these tensions and creates a fluctuation of the normal pressure (hydrostatic+viscous) on the liquid-liquid interface I AB , which deforms. Solution A, called the carried liquid, is a thin film of low viscosity. Film thicknesses between 5 and 200 microns have yielded the best results. As a particularly appropriate liquid I silicone oils having a viscosity between 0.5 and 100 centistrokes may be cited. This liquid I is mixed with an aromatic liquid II, as for example monobromonaphtalene.
FIG. 3 represents a detailed view of the infrared target with a solution B having an index greater than that of solution A, i.e., operating with total reflection. A previously saturated mixture of two liquids is deposited on one of the faces of prism P. The index of the prism is close to that of the carrier liquid, i.e. saturated solution B so that rays of infrared radiation encounter only a single interface, that is, liquid-liquid interface I AB .
The container C containing the liquids and carried by one of the faces of the prism is covered by a glass plate transparent to infrared radiation thereby avoiding the evaporation of the liquids and their contamination.
FIG. 4 is an over-all view of the infrared image converter according to the invention operating with total reflection, that is to say, using the infrared target of FIG. 3. The converter comprises an infrared optical system 0 1 which focuses the radiation to be converted, emanating from an infrared source, not shown, on the free surface of solution A. An infrared image is thus created on the free surface which is converted into a thermal image by the absorption of the infrared radiation thereby causing a deformation of the liquid-liquid interface I AB . There is provided on the other side of the liquid-liquid interface I AB a mono- or polychromatic source S emitting a beam of light rendered parallel after traversing two lenses L 1 and L 2 . The parallel beam of light is totally reflected by the deformed interface. The deformation of the interface is observed by the variation of the intensity of the reflected beam on a screen E placed immediately after prism P.
FIG. 5 represents another embodiment of the target. A two-component saturated solution A is provided in container C carried by a two-component solution B. These solutions result from a combination of two liquids I and II. A reflective grating G, for example of metal, is provided above solution A, the spacing x of the grating is such that the ratio x/d is between 10 and 20 (d being the thickness of the layer of solution A).
Instead of providing a reflective grating G above the solution A it is also possible to arrange it at the level of the interface between solution A and solution B (not shown). With this target it is possible to operate with transmission as well as total reflection.
If operating with total reflection a prism is arranged under solution B (as in FIG. 3).
FIG. 6 represents a third embodiment of the target for use in the converter according to the invention. There is formed, with the aid of radiation absorbed by solution A, image R' of diffraction grating R with the aid of lens L 3 and glass plate L 1 transparent to infrared radiation and reflective for the radiation impinging R. The infrared radiation is projected simultaneously on the target.
The device permits the sensitivity to be doubled relative to that of the target of FIG. 5.
The diffraction grating spacing used is such that the ratio of the spacing of the grating to the thickness of the film of solution A ranges between 10 and 20.
FIG. 7 represents a fourth embodiment of the target which operates with total reflection. A blocked target is constructed by depositing on the two-phase system, solution A solution B, an IR transparent glass plate L. Under the two-phase system is a prism the index of which is substantially equal to that of solution B.
Such a receiver may be used for transmission by eliminating the prism P.
FIG. 8 represents a final embodiment of the target There is provided, as in FIG. 7, a glass plate L and a prism P but the liquid system is not a two-phase but a three-phase system. Three solutions A, B and C are present. Liquid B absorbs infrared radiation, on the other hand liquid A allows infrared radiation to pass therethrough. The interfacial tension between liquids B and C is very low and the thermal variation of the surface tension of the interface between liquids A and B is substantial. The thermal image is detected by the deviation of the rays reflected on the movable interface between B and C.
The interest of this system, as that of FIG. 7, is to have a blocked target of more convenient use.
This target may be used for transmission by eliminating prism P.
FIG. 9 represents the image converter according to the invention operating with normal transmission. This converter comprises an infrared optical system 0 1 which focuses the radiation to be converted, emanating from an infrared source, not shown, on the free surface of solution A contained in container C. An infrared image is thus created on this free surface which is converted into a thermal image by absorption of infrared radiation thereby causing a deformation of the liquid-liquid interface. There is provided on the same side of the liquid-liquid interface as mono- or polychromatic source S emitting a beam of light rendered parallel after traversing two lenses L 1 and L 2 . The parallel beam of light totally reflects on mirror M and traverses target designated C. The deformation of the interface by the variation of the intensity of the beam falling on a screen E placed just after the target, is viewed.
The preferred embodiment of the converter is diagrammatically illustrated in FIG. 10 of the drawings. This converter was realized by the French firm Societe d'Optique, Precision, Electronique et Mecanique (Sopelem) 102, rue Chaptal, Levallois-Perret, France.
The infrared image converter diagrammatically represented in FIG. 10 as an easily transportable compact device for converting into visible images infrared radiation emitted by an object to be monitored.
The device comprises, first of all, means for receiving infrared radiation comprising, in the direction of the radiation, an infrared radiation lens system 11, a diaphragm 12 and a sensitive target or cell designated by general reference number 13.
The lens 11 is made of germanium and is designed for a wave-length of 10 μm. Its focal length is 75 mm, its aperture is f/2, its field of view is 25 mm. The diaphragm 12 is an iris diaphragm.
The target is made up of a glass rhomboherdron 14 and two containers 15 and 16 respectively bonded to two parallel faces 17 and 18 of the rhombohedron. Container 15 contains liquids 19 and 20 which, according to the invention, are partially miscible at operating temperature and pressure. An inert or inactive gas 21, such as dry nitrogen, is provided above the liquid 19. The wall 22 of the container 15 facing the lens 11 is transparent and formed as a germanium window. It goes without saying that the container comprises means (not shown) for making it gas-tight and liquid-tight. The thickness of liquid 19 is of the order of 100 μm and that of liquid 20 is of the order of 1 mm. Container 16 essentially contains a mercury layer or bath 23 separated from the adjacent face 17 of the rhombohedron 14 by a liquid 24 the index of refraction of which is identical with that of the glass of the rhombohedron. The liquids 19 and 20 together form an active interface 25, and liquids 23 and 24 form between each other an interface 26 called a compensating interface. The dimensions of interfaces 25 and 26 are of the order of 40 mm×40 mm, their operative areas being reduced to about 25 mm×25 mm.
The resolving power of the infrared lens 11 must not interfere with the quality of the image yielded by the interface 25. The interface 25 has a resolving power of five lines per millimeter over the entire field.
In the arrangement represented in FIG. 10 lens 11 is mounted vertically above interface 25. Of couse the focus of the lens 11 and the diameter of the aperture of diaphragm 12 may be adjusted. The lens may be focused between one meter and infinity. The aperture of the diaphragm is adjustable from f/2 to f/22. Such adjustments are performed in a manner well known to one having ordinary skill in the art by means of rings mounted on the lens system 11.
In a refined embodiment the lens system 11 may be surmounted by a mirror (not shown). The mirror is then pivotally mounted for displacement in elevation, e.g., between 35° and 55°. The mirror is fixed to the lens system and the lens system-mirror unit forms a module. The elevation control is effected by the support common to the lens system and the mirror.
The device further comprises a collimator designated by general reference 27. The collimator 27 comprises a lens 28, a diaphragm 29, a condenser 30 and a light source 31. The light source 31 comprises a mercury arc lamp, type HBO 50W/3, cooled by free flowing air. Diaphragm 29 has a circular aperture of diameter 50 μm positioned at the focal point of lens 28. The condenser 30, diameter 15 mm and focal distance 15 mm, is interposed between the light source 31 and diaphragm 29. An anticaloric filter (not shown) may be placed between the light source 31 and the condenser 30 as close as possible to the condenser. The lens 28 has a focal length of 105 mm and a relative aperture of f/4 (φ=25 mm). The diffusion spot at the center of the field is 0.5 mrd. Its field is 5 mrd. It is corrected at infinity and treated for visible light.
The face 33 of the rhombohedron facing collimator 27 is perpendicular to central ray 32 emitted thereby. Face 33 is advantageously treated by a nonreflective coating for visible light.
The arrangement of the collimator 27 relative to the target 13 is such that the parallel visible light rays (represented by central ray 32) totally reflecting from active interface 25. The selected angle of reflection is equal to 60°. The beam 35 reflected by the interface 25 is then reflected into compensating interface 26. The reflected beam 36 passes perpendicularly through face 34 of the rhombohedron. Face 34 is also treated with a non-reflective coating for visible light.
The rays 36 emerging from the rhombohedron 14 is processed or viewed in an arrangement which will now be described. The arrangement of assembly, designated by general reference numeral 37 comprises viewing means. The assembly essentially includes anafocal lens system formed by two cylindrical lenses 38 and 39. The divergent lens 38, 10 diopters (f=100 mm), has an operative area of 13 mm×25 mm. The convergent lens 39, five diopters (f=200 mm) has a diameter of 25 mm. After convergent lens 39 in the direction of the rays 36 the viewing means comprises a Porro prism 40. The prism 40 is composed of four mirrors defining two perpendicular dihedral angles. The first dihedral is stationary and the second dihedral is movable along a short distance (e.g. 10 cm) parallel to the middle incident ray.
The beam of visible rays emerging from the Porro prism 40 is received on a screen 41. The screen comprises, for example, a ground glass plate on one side, the ground glass plate facing a bi-ocular lens 42. The biocular lens has a focal length of 80 mm, the screen being located at 75 mm from its main plane, thereby ultimately forming a virtual image at one meter from the screen.
The device diagrammatically represented in FIG. 10 and described hereinabove operates as follows. The infrared radiation emitted by the object 10 is focused in the lens system 10 to form an infrared image on the less dense liquid 19. The less dense liquid 19 is heated locally in accordance with the pattern of the image of the object 10. Since the surface tension between liquids 19 and 20 contained in the first container 15 varies with temperature, the interface 25 between liquids 19 and 20 deforms and in turn may act as an object.
The collimator 27 illuminates interface 25 with parallel visible light at an angle of incidence producing total reflection from interface 25 (angle of reflection equal to 60°). The beam reflected by the interface 25 traverses the rhombohedron 14, and is in turn reflected from the mercury layer 23 (compensating interface 26) contained in the second container 16. The beam carries a visible image corresponding to the deformation of interface 25. Still, direct viewing of the image is not possible because it is inverted and anamorphized. The reflected beam 36 is then processed by the afocal lens system (magnification 2X) including lenses 38 and 39, and by Porro prism 40 which erects the image. The image is formed on the ground glass plate 41 which is viewed through a bi-ocular lens 42.
Thanks to the device represented in FIG. 10 the free surface 23 of the mercury remains permanently parallel to active interface 25 thus having a compensation function. The parallel beam emerging from collimator 27 traverses the target 13 retaining on the average its initial direction. The unit made up by the collimator 27 and the viewing means 37 thus remains in a stationary position relative to the target 13. Such an arrangement provides compensation for changes of direction of orientation of the device and avoids optical adjustments after displacement even if the target is not maintained horizontally.
The rest of the description will be made with reference to examples of practical preparations of the combination of liquids I and II.
EXAMPLE I
Liquid I is a silicone oil (polydimethylsiloxane mixture) and liquid II is a monobromonaphtalene.
The physical properties of the pure liquids are indicated in the following table:
______________________________________ Mono- bromonaphtalene Silicone oil______________________________________Surface tension ofpure liquid with airat 20° C. 37.5 dyne/cm 18.5 dyne/cmspecific gravity at20° C. 1.48 g/cm.sup.3 0.9 g/cm.sup.3refractive index forD line of sodiumat 20° C. 1.658 1.396kinematic viscosity at20° C. 3.56 × 10.sup.-2 stoke 2.83 × 10.sup.-2 stokeheat conductivity 3 × 10.sup.-4 W/cm. °C.specific heat 0.33 cal/g °C.diffusivity 10.sup.-3 cm.sup.2 /sec.______________________________________
The physical properties of the system are as follows:
Surface tension of the monobromonaphtalene saturated with silicone oil with air:
21.5 dynes/cm at 20° C.
Surface tension of Silicone oil saturated with monobromonaphtalene with air:
19.6 dynes/cm at 20° C.
Surface tension of the surface of separation between the two mutually saturated solutions:
0.8 dyne/cm at 20° C.
Kinematic viscosity at 20° C. of the monobromonaphtalene saturated with oil:
3.55×10 -2 stoke
Kinematic viscosity at 20° C. of the oil saturated with monobromonaphtalene:
2.77×10 -2 stoke
The association of these two liquids is seen to permit a very low surface tension to be obtained, therefore susceptible of being deformed easily.
The expression (i/αAB) (dαA/dT) may be used at the criterion of sensitivity of the converter according to the present invention, α A designating the surface tension of saturated solution A with air, and α AB designating the surface tension of the interface I A-B .
Indeed dα/dT A represents the thermal effect which destabilizes the saturated solution A and generates convection currents.
That is the motor effect and (1/αAB) represents the mechanical effect of the aforesaid instability which acts on the liquid-liquid interface and deforms it.
That is the sought-after effect.
Assuming that the deformation of the liquid-liquid interface is slight relative to the thickness of the film of solution A which is so in practice, it is found that for a given sensitivity:
(1/αAB) (dO.sub.A /dT)
the deflection of the interface is inversely proportional to the thickness of solution A. Moreover, the thickness of solution A may not be diminished indefinitely: the deformation of the interface must follow the variations in temperature of the solution A with a low time constant. The thickness of the saturated solution A therefore is a minimum which taking account the thermal sensitivity sought and the spatial resolution desired, must be suitably selected as a function of the parameters of the materials. In an actual construction a time constant of the order of 1/10 second was obtained with a thickness of the solution A of about 100 microns.
EXAMPLE II
This example concerns other usable liquids I and II and combinations of such liquids.
(1) Liquid II-monobromonaphtalene (n=1.66 d=1.48).
Liquid I acetic acid--CTS 42° C.
methanol--CTS 62° C.
phenylacetic acid--CTS 55° C.
(2) Liquid II--carbon tetrachloride CC1 4 (n=1.46) (d=1.60)
Liquid I acetic acid--CTS 25° C.
butyric acid--CTS 25° C.
diphenylamine--CTS 28° C.
propionic acid--CTS 25° C.
p-nitrochlorobenzene--CTS 50° C.
(3) Liquid II--carbon sulfide CS 2 (n=1.628) (d=1.30)
Liquid I acetic anhydride--CTS 30° C.
acetonitrile--CTS 51.5° C.
butyric acid--CTS 25° C.
camphor--CTS 25° C.
formic acid--CTS 43° C.
methanol--CTS 36° C.
p-nitrochlorobenzene--CTS 50° C.
propionic acid--CTS 25° C.
(4) Liquid II methylene iodide CH 2 I 2 (n=1.742).
Liquid I cyclopentane CTS 30.5° C.
methylcyclopentane CTS 44° C.
cyclohexane CTS 31°0 C.
methylcyclohexane CTS 45° C.
acetic acid CTS 45° C.
(CTS is the Critical Temperature of the Solution) (n is the refractive index for the D line of sodium at 20° C.) (d=density at 20° C.). | A converter and method of converting thermal images into secondary images, e.g. visible images. The infrared radiation emitted by an object is focused by an optical system to form a thermal image on the free surface of a thermal radiation absorbing layer to one side of a liquid-liquid interface which has low surface tension and is a mixture of two liquid partially miscible at operating temperature and pressure. To convert the thermal image to a visible a parallel beam of light or a beam of light from a point source in the visible range is directed to the other side of the interface and, depending on the selected indices of the interface liquids and whether a prism is used or not; is either transmitted or reflected. The emerging transmitted or reflected beam is then received on a screen or in a detection system where variations of the optical properties of the emerging beam are observed. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a loudspeaker system and a noise canceling apparatus. More specifically, the present invention relates to a loudspeaker system in which a predetermined number of flat loudspeaker units are disposed in a coupled manner in the longitudinal direction of a cabinet, wherein the flat loudspeaker unit is structured with a plurality of small sound cells placed vertically and horizontally, and to a noise canceling apparatus for canceling noises using this loudspeaker system.
[0003] 2. Description of the Related Art
[0004] Loudspeakers for commercial use and those for household use are generally of cone type. Normally, this type of loudspeaker is used such that a plurality of such loudspeakers are arranged in a certain place in a manner that is suitable for that space.
[0005] According to such conventional art, there have been problems in that locations at which these loudspeakers can be installed are limited by the size of the loudspeaker and/or the condition of the installation space, and that when loud sounds are required in a large space, the size of the loudspeaker must be large.
[0006] Moreover, there has been another problem in that since the installation place of the loudspeaker is a source of the sound, the sound source will be a point sound source, so that the volume and tone sound different depending on a position of a listener.
[0007] Further, there has been another problem in that the sound might be deformed and/or distorted depending on the spatial condition.
SUMMARY OF THE INVENTION
[0008] In order to solve the aforementioned problems, a loudspeaker system of the present invention includes a plurality of flat loudspeaker units arranged and fixed linearly in the longitudinal direction of an elongated opening provided at a side portion of a cabinet, wherein the plurality of flat loudspeaker units form a base unit.
[0009] According to the loudspeaker system of the present invention, since the plurality of flat loudspeaker units are arranged and fixed linearly in the longitudinal direction of the elongated opening provided at a side portion of the cabinet, a series of sound sources extending linearly can be obtained.
[0010] Moreover, by arranging the plurality of flat loudspeaker units linearly, sounds output from the flat loudspeaker units are synthesized to thereby increase the energy.
[0011] The loudspeaker system of the present invention has an effect of making it possible for a listener to hear sounds having the same quality anywhere along the cabinet, and that the sound is not perceived as noisy even in a position close to the loudspeaker and is also perceived as clearly in a position far from the loudspeaker as it is perceived in the closer position since the loudspeaker system of the present invention outputs sounds with plane waves having little attenuation unlike loudspeaker systems with cone loudspeakers.
[0012] A noise canceling apparatus, which is another aspect of the present invention, utilizes the above-described loudspeaker system and outputs a sound having an opposite phase to a sound picked up by a microphone from the flat loudspeaker unit, thereby enabling it to cancel noises and the like.
[0013] In the noise canceling apparatus of the present invention, the position of a diaphragm of the microphone and the position of a driving plate of the flat loudspeaker unit are in the same plane, so that noises can be canceled with a simple structure and does not require any complex control.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is a partial front view for explanation of a base unit in a state in which a cover is off.
[0015] [0015]FIG. 2 is a partial side view for explanation of the base unit in a state in which the cover is on.
[0016] [0016]FIG. 3 is a cross-sectional view along line A-A in FIG. 2.
[0017] [0017]FIG. 4 is a diagram for explanation showing a state of a partition and a sound absorbing material.
[0018] [0018]FIGS. 5A, 5B, and 5 C are diagrams for explanation showing examples of shapes of a connecting material.
[0019] [0019]FIG. 5D is a side view of a loudspeaker system in which the base units are connected by using the connecting materials.
[0020] [0020]FIG. 6 is an exploded view of a base unit according to a second embodiment.
[0021] [0021]FIG. 7 is a cross-sectional view of the base unit according to the second embodiment.
[0022] [0022]FIG. 8A is a side view of a baffle board seen from a projection side.
[0023] [0023]FIG. 8B is a side view of the baffle board seen from a side surface side of a rib.
[0024] [0024]FIG. 8C is a back view of the baffle board.
[0025] [0025]FIG. 9 is a diagram for explanation showing the baffle boards in a connected state.
[0026] [0026]FIG. 10 is a front view of a bracket.
[0027] [0027]FIG. 11 is a side view of the bracket.
[0028] [0028]FIG. 12 is a cross-sectional view of the base unit showing a mounting portion of a speaker grille.
[0029] [0029]FIG. 13 is a cross-sectional view of a base unit according to a third embodiment.
[0030] [0030]FIG. 14 is a diagram for explanation showing a placement of the base unit when reducing noises.
[0031] [0031]FIG. 15 is a diagram for explanation in a case in which the base units are mounted to sound-proof walls of a road.
[0032] [0032]FIG. 16 is a cross-sectional view of a base unit according to a fourth embodiment.
[0033] [0033]FIG. 17 is a diagram for explanation showing a placement of the base unit when reducing noises.
[0034] [0034]FIG. 18 is an exploded perspective view of a flat loudspeaker unit.
[0035] [0035]FIG. 19 is a cross-sectional view of the flat loudspeaker unit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] [First Embodiment]
[0037] Referring to the drawings, a first embodiment of the present invention will be described hereinafter.
[0038] [0038]FIG. 1 is a partial front view for explanation of a base unit 2 in a state in which flat loudspeaker units 1 are disposed in a pipe 3 . FIG. 2 is a partial side view for explanation of the base unit 2 and FIG. 3 is a cross-sectional view for explanation of the base unit 2 .
[0039] A loudspeaker referred to as a multi-cell flat loudspeaker described in, for example, PCT/JP00/03755 and others can be used as the flat loudspeaker unit 1 . These loudspeakers vary in size and all of them can be used.
[0040] The present embodiment will be described using the flat loudspeaker unit 1 having a size of 40 mm in length, 160 mm in width, and 6 mm in thickness.
[0041] As shown in FIGS. 18 and 19, the flat loudspeaker unit 1 is provided with a yoke 120 consisting of a flat member formed of a magnetic substance.
[0042] On a magnet fixing portion 120 A of the yoke 120 , a plurality of permanent magnets 122 with a flat rectangular shape are fixedly disposed by adhesion in a manner in which pole faces having different polarity are placed alternately at predetermined intervals, and the pole face of each magnet faces upward as shown in FIGS. 18 and 19.
[0043] On an upper surface side of the yoke 120 , a diaphragm 1 A is disposed in close vicinity to the pole faces in such a manner that the diaphragm is parallel to the pole face of the permanent magnets 122 , and thus to the upper surface of the yoke 120 .
[0044] On a diaphragm mounting portion 120 B of the yoke 120 , an outer peripheral edge of a frame body 124 with a rectangular frame shape is fixed with a spacer 125 made of paper or the like provided therebetween.
[0045] On the frame body 124 , an edge 127 , which is a resilient portion having a semi-circular arcuate cross-section, is formed continuously along the outer peripheral edge.
[0046] An outer peripheral edge of the diaphragm 1 A is adhered to an inner edge side of the frame body 124 .
[0047] On the diaphragm 1 A, spirally formed coils 126 are disposed so as to correspond to each of the permanent magnets 122 .
[0048] Each coil 126 is formed with a spirally winding structure so as to have a configuration substantially similar to the outer edge of the permanent magnet 122 .
[0049] Moreover, in order to form an air layer with a predetermined thickness between the permanent magnets 122 and the diaphragm 1 A, the pole face of the plurality of permanent magnets 122 is covered with a sheet material 128 adhered thereto.
[0050] On each coil 126 , magnetic fluxes facing a substantially parallel direction with respect to the diaphragm surface are interlinked.
[0051] When an electric current passes through the coil 126 , the diaphragm 1 A is subjected to a force perpendicular to the surface of the diaphragm, so that the diaphragm 1 A is displaced in a direction perpendicular to the surface of the diaphragm.
[0052] Therefore, by energizing the coil 126 with electric signals that indicate sounds that are to be generated, the diaphragm 1 A is vibrated according to the electric signals to thereby enable sound signals to be generated.
[0053] In the present embodiment, twelve flat loudspeaker units 1 are disposed in a connected row arrangement and fixed in the pipe 3 to thereby form a single base unit 2 .
[0054] In accordance with the present invention, there is no limitation on the number of the flat loudspeaker units 1 provided in a connected row arrangement and, for example, two, four, eight, or twenty-four flat loudspeaker units 1 may be disposed in a connected row arrangement and fixed in the pipe 3 .
[0055] While the base unit 2 can be used alone, any desired number of the base units 2 may be connected and used together.
[0056] Moreover, the plurality of flat loudspeaker units 1 may either be electrically connected serially or in parallel, or may be connected by combining serial and parallel connections.
[0057] According to the above-described dimension of the flat loudspeaker unit 1 , when the total length of the base unit 2 is set to 170 cm, the base unit 2 functions as a resonant pipe to amplify the frequency band with a resonance frequency of 49 Hz, 147 Hz, and 245 Hz. Thus, the low frequency band can be amplified.
[0058] In connecting each of the flat loudspeaker units 1 to form the base unit 2 , the narrower the space between each of the flat loudspeaker units 1 , the better the synthesis of the high frequency band. Thus, in the present embodiment, the flat loudspeaker units 1 are connected along the longitudinal direction of the pipe 3 as shown in FIG. 1, wherein the space between each of the diaphragms 1 A is 14 mm, thereby enabling smooth synthesis of the high frequency band for a synthesized frequency of up to 24000 Hz.
[0059] Further, to withstand the large sound volume, the distance between the diaphragm 1 A and the permanent magnet 122 of the flat loudspeaker unit 1 is widened (0.2 mm in the present embodiment), and accordingly, the magnetic flux density of the permanent magnet 122 is made higher thus improving the performance of the material of the diaphragm 1 A.
[0060] As a specific structure of the base unit 2 , the material of the pipe 3 could be any material such as metal, wood, paper, synthetic resin and the like. An opening 4 is provided in the side portion in the longitudinal direction of the pipe 3 having a desired diameter (an internal diameter of 50 mm in the present embodiment), and a fixing portion 5 is formed at the inner periphery of the opening 4 .
[0061] The cross-sectional form of the pipe 3 can be of any shape such as circular, elliptical, polygonal and the like.
[0062] The fixing portion 5 is a portion which fixes the flat loudspeaker units 1 disposed in a connected row arrangement, and any fixing means may be used. For example, the flat loudspeaker units 1 may be fixed, by being screwed directly or via an anchoring member, and are fixed by disposing a resonance preventing material 6 made of an elastic material such as a rubber board, a synthetic resin board, a cork board, or the like between the flat loudspeaker units 1 and the fixing portion 5 .
[0063] Depending on the wall thickness of the pipe, the flat loudspeaker units 1 may be fixed directly on the end face of the opening without forming the fixing portion 5 .
[0064] In some cases, the flat loudspeaker units 1 may also be fixed by using an adhesive agent rather than by being screwed or the like.
[0065] In the pipe 3 , it is preferable if partitions 7 are formed at the connecting points in order to prevent an acoustic resonance for each flat loudspeaker unit 1 . The partition 7 may either divide the space within the pipe 3 completely by filling the entire inner perimeter of the pipe 3 , or a space may be left between the upper edge of the partition 7 and the back surface of the flat loudspeaker unit 1 .
[0066] It will also be advantageous if a sound absorbing material 8 is provided in the pipe 3 in order to reduce an internal resonance of a low frequency band.
[0067] The sound absorbing material 8 may either fill the space within the pipe 3 , or a space may be left below the back surface of the flat loudspeaker unit 1 . In either case, the structure must be such that wiring can be passed through.
[0068] The both ends of the pipe 3 of the base unit 2 or a small unit are closed with shutoff boards 9 . On the shutoff board 9 , a small wiring hole (not shown) is formed.
[0069] In order to connect such base units 2 or small units, bolts and nuts, or the like are used to fixedly couple them tightly.
[0070] In connecting the base units 2 , a connecting material 10 such as one shown in FIGS. 5A to 5 C may be disposed between the base units 2 . The total length of the loudspeaker system can be adjusted by adjusting the length of the connecting material 10 .
[0071] It is structurally advantageous for total length of the base unit 2 be 180 cm when it is being at the installation site in light of architectural dimensions. However, the length of the base unit 2 may be suitably determined according to the purpose, and is not limited to 180 cm.
[0072] Moreover, as shown in FIGS. 5A to 5 C, the connecting material 10 may not only have a linear shape but can be deformed by being bent or curved with a desired angle, thereby allowing it to be connected at the connecting portion with a desired curved angle. Accordingly, the loudspeaker system can be bent at each base unit 2 or small unit, as shown in FIG. 5D, according to the installation location.
[0073] At the desired position in the pipe 3 , a connector 11 for connecting a loudspeaker cable is built-in.
[0074] On the connecting material 10 , a through hole 10 A for passing the wiring therethrough, which is used in connecting the flat loudspeaker unit 1 of one base unit 2 and that of another base unit 2 , is formed.
[0075] A transformer for a high impedance transmission may also be installed inside the connecting material 10 .
[0076] A cover 12 formed of a perforated metal, a mesh body, or the like having innumerable small holes is mounted to the opening 4 in the side portion of such pipe 3 , where the flat loudspeaker units 1 are mounted, to thereby form an output surface 4 .
[0077] This output surface 4 may have a curved shape in accordance with the curved surface when the pipe 3 is a cylinder, or if the pipe 3 has another shape, the output surface may accordingly have a matching shape. However, the shape of the output surface 4 does not have to match the shape of the pipe 3 , and any desired shape such as a curved surface or a flat surface may be applicable.
[0078] In accordance with the loudspeaker system having the above-described structure, the sounds output from the flat loudspeaker units 1 are synthesized due to the plurality of serially-arranged flat loudspeaker units 1 in the pipe, thereby increasing the energy.
[0079] Therefore, the loudspeaker system according to the present embodiment may, as a matter of course, be used as a loudspeaker which is an ordinary acoustic equipment, but it also can be used as a broadcasting equipment in larger spaces such in the vicinity of an escalator, on a platform in a station, or at an airport by utilizing the characteristic of a sound source having a particular shape or having a linear shape which outputs plane waves. That is, the characteristic is utilized which, because the listener can hear the sounds all along the loudspeaker system, allows a listener to perceive the same sounds as being close all the time rather than as being loud.
[0080] Moreover, by utilizing the cylindrical shape of the base unit 2 , the loudspeaker system can be used in a long range as, for example, a loudspeaker system which also serves as a hand rail.
[0081] Further, using appropriate materials and/or colors, the loudspeaker system can be disposed so as to be camouflaged.
[0082] [Second Embodiment]
[0083] A second embodiment of the present invention will be described hereinafter. The same reference numerals are used to designate identical structures with those of the first embodiment, and description thereof will be omitted.
[0084] As illustrated in FIG. 6, in a base unit 20 of the present embodiment, a baffle board assembly 30 composed of a baffle board 22 , the flat loudspeaker unit 1 , a speaker grille 24 , a resonance preventing material 26 , and a bracket 28 is mounted detachably by means of a screw 34 to an extruded material 32 made of an aluminum alloy.
[0085] While FIG. 6 shows a state before mounting the baffle board assembly 30 to the extruded material 32 , FIG. 7 shows a mounted state of the baffle board assembly 30 to the extruded material 32 .
[0086] The extruded material 32 has a substantially C-shaped cross-section, and a pair of setscrew portions 36 protrude at the internal surface in the vicinity of the opening.
[0087] On the leading edge of the setscrew portion 36 , a groove 38 having a substantially round cross-section is formed.
[0088] In the both longitudinal direction ends of the extruded material 32 , round shutoff boards (not shown) are provided.
[0089] This shutoff board is mounted to the extruded material 32 by screwing a screw, which is passed through a hole formed on the shutoff board, into the groove 38 .
[0090] At the base of the screw stop portion 36 , a step portion 40 is formed.
[0091] As illustrated in FIG. 8, the baffle board 22 is a molded product of synthetic resin, and is formed with a frame shape.
[0092] As shown in FIG. 8C, on the underside of the baffle board 22 , a pair of loudspeaker mounting faces 42 are formed, and the central portion of each loudspeaker mounting face is open with a rectangular shape.
[0093] In the both transverse direction ends of the loudspeaker mounting face 42 , ribs 44 are formed.
[0094] As shown in FIGS. 8A and 8C, on the rib 44 , a bracket mounting face 46 is formed such that the bracket mounting face 46 is parallel to the loudspeaker mounting face 42 .
[0095] As illustrated in FIG. 8C, on the bracket mounting face 46 , a plurality of screw holes 48 are formed.
[0096] As illustrated in FIG. 8B, on the side surface of the rib 44 , a plurality of screw holes 50 for screwing the speaker grille 24 (described later) are formed.
[0097] At one side in the longitudinal direction of the baffle board 22 , a pair of projections 52 are formed.
[0098] At the other side in the longitudinal direction of the baffle board 22 , a pair of recess portions 54 into which the projections 52 fit are formed.
[0099] When a plurality of baffle boards 22 are connected in the longitudinal direction, the projection 52 of one baffle board 22 and the recess portion 54 of another baffle board 22 are fit together as shown in FIG. 9.
[0100] The bracket 28 is a press molded product made of a metal plate.
[0101] As illustrated in FIG. 10, the bracket 28 is provided with a board mounting portion 56 which is brought into contact with the bracket mounting face 46 of the baffle board 22 . On the board mounting portion 56 , a plurality of mounting holes 58 are formed.
[0102] As shown in FIGS. 6, 10 and 11 , on the board mounting portion 56 , loudspeaker presser pieces 60 bent at right angle and an extending portion 62 which extends so as to be inclined toward the backface side of the extruded material 32 are formed integrally.
[0103] The leading edge of one extending portion 62 and that of the other extending portion 62 are connected with each other via a connecting portion 64 .
[0104] In the middle of the connecting portion 64 , a female thread 66 is formed.
[0105] The flat loudspeaker unit 1 is fixed between the loudspeaker presser piece 60 and the loudspeaker mounting face 42 in a manner that the flat loudspeaker unit 1 is set in close contact with the loudspeaker mounting face 42 of the baffle board 22 via the sheet-shaped resonance preventing material 26 made of an elastic material, and a screw 68 which is passed through the mounting hole 58 on the board mounting portion 56 of the bracket 28 is screwed into the screw hole 48 formed on the bracket mounting face 46 of the baffle board 22 .
[0106] Since the plurality of screw holes 48 are formed on the baffle board 22 , the bracket 28 can be mounted at the desired position on the baffle board 22 . For example, when a plurality of baffle boards 22 are connected in the longitudinal direction as shown in FIG. 9, the baffle boards 22 can be fixed to with each other by mounting the bracket 28 using the screw holes 48 which are closest to the connecting portion.
[0107] As illustrated in FIG. 6, at the surface side of the baffle board 22 , the speaker grille 24 is provided.
[0108] This speaker grille 24 is formed by curving a perforated metal.
[0109] As shown in FIG. 12, the speaker grille 24 is fixed to the side surface of the rib 44 by a flat countersunk head screw 72 .
[0110] As shown in FIGS. 8A and 8B, arcuate supporting portions 74 which support the speaker grille 24 from the underside are formed at the both longitudinal direction ends and at the central portion in the longitudinal direction of the baffle board 22 .
[0111] As shown in FIG. 6, a mounting hole 76 is formed in the backface of the extruded material 32 .
[0112] The baffle board assembly 30 is pulled toward the backface side of the extruded material 32 in a manner that the screw 34 passed through the mounting hole 76 is screwed into the screw hole 66 on the bracket 28 , and the corner portion of the rib 44 is set in tight contact with the step portion 40 of the extruded material 32 with a sheet-shaped resonance preventing material 78 made of an elastic material being provided therebetween.
[0113] In the same manner as the first embodiment, the sound absorbing material 8 may be adhered to the internal surface of the extruded material 32 .
[0114] In the present embodiment, the baffle board assembly 30 can be easily attached to the extruded material 32 by means of the screw 34 .
[0115] Generally, loudspeakers are fixed by being screwed from the front side of a cabinet, so that a flange is formed on the frame of each loudspeaker and a plurality of mounting holes for inserting screws into the flange are formed.
[0116] Since the loudspeaker is fixed to the cabinet at the flange portion, the flange is required to have certain proportions.
[0117] Therefore, when a plurality of such loudspeakers are placed adjacent to each other, the flanges interfere with each other, preventing the diaphragms from being disposed close to each other.
[0118] At this point, when an attempt is made to output loud sounds in a large space by utilizing a plurality of loudspeakers, there will be a problem in that the high frequency band attenuates unless diaphragms are brought closer to each other.
[0119] However, in the present embodiment, since the flat loudspeaker unit 1 is not mounted from the front side by means of screws, the area of the frame of the flat loudspeaker unit 1 can be minimized and the diaphragms can be set closer to each other than in conventional methods for mounting a loudspeaker. Accordingly, even when a number of flat loudspeaker units 1 are disposed in a continuous line arrangement, attenuation of the high frequency band can be prevented.
[0120] [Third Embodiment]
[0121] A third embodiment of the present invention will be described hereinafter. The same reference numerals are used to designate identical structures with those of the above-described embodiments, and description thereof will be omitted.
[0122] As illustrated in FIG. 13, on the baffle board 22 in the base unit 2 of the present embodiment, a hole 82 passing through the baffle board 22 is formed.
[0123] A microphone 84 is inserted into the hole 82 and fixed by means of adhesive or the like.
[0124] A sound receiving surface of the microphone 84 is directed to the speaker grille side.
[0125] The microphone 84 is provided with a planar diaphragm 84 A, and the diaphragm 1 A of the flat loudspeaker unit 1 and the diaphragm 84 A of the microphone 84 are placed in the same plane.
[0126] The microphone 84 may be a microphone having conventionally known structures such as condenser type microphone, dynamic type microphone or the like.
[0127] The base unit 2 of the present embodiment can output sound from the flat loudspeaker unit 1 and pick up the ambient sound from the microphone 84 .
[0128] By using this base unit 2 , a noise canceling apparatus for reducing a particular sound such as undesired noise can also be structured.
[0129] When the base unit 2 is used as the noise canceling apparatus, the front side of the base unit 2 is directed to a noise source 86 , for example, and a noise N output from the noise source 86 is picked up from the microphone 84 as shown in FIG. 14. Then, signals from the microphone 84 are phase-inverted at a control circuit 87 , the phase-inverted signals are amplified to be output to the flat loudspeaker unit 1 , and a canceling sound UN having an opposite phase to the picked up noise N is output from the flat loudspeaker unit 1 to cancel the noise N.
[0130] Conventionally, various systems for canceling noise by picking up noise by a microphone and then by outputting a sound having an opposite phase to the noise from a loudspeaker have been made for practical use. However, those are combinations of a cone type loudspeaker and a microphone, and a diaphragm of the loudspeaker and a diaphragm of the microphone are not placed in the same plane.
[0131] A first drawback of the conventional system is, since a noise pick up position (the location of the diaphragm of the microphone) and a noise cancel sound outputting position (the location of the diaphragm of the loudspeaker) are different with respect to a point of the noise source, there has been a problem in which complicated operations are required prior to outputting sound. Moreover, the control circuit is intricate, and complex noises (such as a mixture of plural sounds having different frequency or level) cannot be reduced effectively.
[0132] However, in the noise canceling apparatus employing the base unit 2 of the present embodiment, since the location of the diaphragm 84 A of the microphone 84 and the location of the diaphragm 1 A of the flat loudspeaker unit 1 are set in the same plane, what is required for the control circuit 87 are only phase inversion and level control, thereby enabling cancellation of the noise N with a simple structure. When the wire connected to the flat loudspeaker unit 1 is reversed, the phase is automatically inverted.
[0133] Moreover, as a second drawback of the conventional system, since cone type loudspeakers are being used, the noise canceling sound is not a plane wave.
[0134] Accordingly, when a plurality of loudspeakers are used, the waveform of the noise canceling sound become mixed up, so that the noise canceling effect is insufficient.
[0135] However, in the base unit 2 of the present embodiment, since the diaphragms 1 A of the plurality of flat loudspeaker units 1 are disposed in the same plane, plane waves can be output regardless of the number of flat loudspeaker unit 1 , thereby ensuring the cancellation of the noise N.
[0136] As illustrated in FIG. 15, a plurality of noise canceling apparatuses employing the base unit 2 may also be connected along the top end of sound-proof walls 90 on a road 88 .
[0137] In this case, the microphone 84 picks up the noise N of a vehicle 92 , and the noise canceling sound UN having an opposite phase to the picked up noise N is output from the flat loudspeaker unit 1 to thereby enable cancellation of the noise N of the vehicle 92 . Accordingly, the noise N which might be heard outside the sound-proof walls 90 can be reduced.
[0138] In a single base unit 2 , the number of microphone 84 may either be one or more.
[0139] For example, in a case in which a plurality of microphones 84 are provided in a single base unit 2 , the plurality of microphones 84 are disposed at certain (e.g., regular) intervals, and one microphone 84 and one or more flat loudspeaker units 1 placed closest to the microphone 84 make a pair so that the noise canceling sound UN having an opposite phase to the noise N picked up by the microphone 84 is output from the one or more flat loudspeaker units 1 which is paired with the microphone 84 .
[0140] When the base unit 2 is long, such a case is conceivable in which the level, frequency or the like of the noise differs for every region in the longitudinal direction. However, by placing the plurality of microphones 84 as described above, it is possible to ensure reduction of the noise N which differs in every region.
[0141] Moreover, although the microphone 84 which is a separate component from the flat loudspeaker unit 1 is used in the present embodiment, by not using the above-described microphone 84 for example, one of the plurality of flat loudspeaker units 1 or the like having the similar structure to that of the flat loudspeaker unit 1 can also be used instead of the microphone 84 .
[0142] Further, a portion of the flat loudspeaker unit 1 can also be used as a microphone without using the above-described microphone 84 .
[0143] For example, one or more coils 126 in the flat loudspeaker unit 1 are electrically disconnected from the other coils 126 (the ones used as the loudspeaker), and the electrically disconnected coils 126 can be used as coils for the microphone while a portion of the diaphragm 1 A on which the electrically disconnected coils 126 are formed can be used as a diaphragm of the microphone.
[0144] If the microphone 84 is not used in this manner, the number of parts can be reduced.
[0145] [Fourth Embodiment]
[0146] A fourth embodiment of the present invention will be described hereinafter. The same reference numerals are used to designate identical structures with those of the above-described embodiments, and description thereof will be omitted.
[0147] As illustrated in FIG. 16, in the base unit 2 of the present embodiment, a mounting plate 94 is fixed to the baffle board 22 by means of screw or the like.
[0148] In the middle of the mounting plate 94 , a hole 96 is formed.
[0149] In the hole 96 , the microphone 84 is inserted and fixed by adhesive or the like.
[0150] The microphone 84 is disposed between the two flat loudspeaker units 1 .
[0151] As illustrated in FIG. 17, in the base unit 2 of the present embodiment, three microphones 84 are placed at regular intervals, and one microphone 84 and two flat loudspeaker units 1 in each of the both sides in the longitudinal direction of the base unit 2 (i.e., four flat loudspeaker units 1 in total) form a pair.
[0152] For the microphone 84 , a microphone having a diameter as small as possible is used in order to keep intervals between the flat loudspeaker units 1 from becoming wide.
[0153] As shown in FIG. 16, a sound receiving surface of the microphone 84 is directed to the backface of the extruded material 32 .
[0154] The diaphragm 1 A of the flat loudspeaker unit 1 and the diaphragm 84 A of the microphone 84 are placed in the same plane.
[0155] On the backface of the extruded material 32 , holes 98 are formed, and a cup-shaped block member 100 is inserted in the holes 98 .
[0156] The outer peripheral portion of the block member 100 in the vicinity of the opening and the inner peripheral portion of the hole 98 of the extruded material 32 are set into tight contact.
[0157] A bottom portion 100 A of the block member 100 and the mounting plate 94 are linked together by a spacer 102 , a screw 104 , and a nut 106 .
[0158] In accordance with the base unit 2 of the present embodiment, as shown in FIG. 17 for example, the microphone 84 is directed to the noise source 86 , the noise N output from the noise source 86 is picked up by the microphone 84 , and the noise canceling sound UN having an opposite phase to the picked up noise N is output from the flat loudspeaker 1 to thereby cancel the noise in the front side of the base unit 2 .
[0159] As described above, the loudspeaker system according to the present invention is suitable for placement in large spaces and for use as a broadcasting equipment in large spaces such in a vicinity of an escalator, on a platform in a station, or at an air port, where it is desirable that the volume and tone of the sound are heard uniformly regardless of listening positions.
[0160] Moreover, the noise canceling apparatus according to the present invention is suitable for location in a place where noise reduction is required. For example, it is suitable for mounting on sound-proof walls on a road or the like to reduce the noise of vehicles. | In a loudspeaker system of the present invention, a plurality of flat loudspeaker units are arranged and fixed linearly in the longitudinal direction of an elongated opening provided at a side portion of a cabinet to form a base unit. In such a manner, a series of sound sources extending linearly can be achieved, and at the same time, sounds output from the flat loudspeaker units are synthesized to thereby increase the energy. Accordingly, a listener can listen to sounds under the same condition anywhere along the cabinet. Moreover, the loudspeaker system of the present invention has an effect in that the sound is not perceived as noisy even in a position close to the loudspeaker while the sound is perceived as clearly in a position far from the loudspeaker as it is perceived in the closer position. | 7 |
[0001] The present application claims the priority of U.S. Provisional Patent Application serial No. 60/374,922 filed Apr. 23, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates generally to an improved arrangement for packaging multiple hydrocyclone separators, especially those used for petroleum fluid processing.
[0004] 2. Description of the Related Art
[0005] The overall construction and manner of operation of hydrocyclone separators is well known. A typical hydrocyclone includes an elongated tapered separation chamber or circular cross-section, which decreases in cross-sectional size from a large overflow and input end to an underflow end. An overflow or reject outlet for the lighter fraction is provided at the base of the conical chamber while the heavier underflow or accept fraction of the suspension exits through an axially arranged underflow outlet at the opposite end of the conical chamber.
[0006] Liquids and suspended particles are introduced into the chamber via one or more tangentially directed inlets. These are adjacent to the overflow end of the separation chamber to create a fluid vortex therein. The centrifugal forces created by this vortex throw denser fluids and particles in suspension outwardly toward the wall of the conical chamber, thus giving a concentration of denser fluids and particles adjacent thereto, while the less dense fluids are brought toward the center of the chamber. As the denser fluids and particles continue to spiral towards the small end of the conical chamber, the lighter fractions are forced to move by differential forces in the reverse direction towards the reject outlet. The lighter fractions are thus carried outwardly through the overflow outlet. The heavier particles continue to spiral along the interior wall of the hydrocyclone and eventually pass outwardly via the underflow outlet.
[0007] The fluid velocities within a hydrocyclone are high enough that the dynamic forces produced therein are sufficiently high to overcome the effect of any gravitational forces on the performance of the device. Hydrocyclones may therefore be arranged in various physical orientations without affecting performance. Hydrocyclones are commonly arranged in large banks of several dozen or even several hundred hydrocyclones with suitable intake, overflow, and underflow assemblies arranged for communication with the intake, overflow and underflow openings respectively of the hydrocyclones.
[0008] Earlier separator systems involving large numbers of hydrocyclone separators commonly employed complex systems of intake, overflow, and underflow pipes or conduits which occupied a substantial amount of space and which required costly and complex support structures for the piping systems involved. It is desired to reduce the space occupied by hydrocyclone assemblies and provide a relatively compact arrangement, especially in the petroleum industry, where offshore platform applications and ship-based installations put a premium on space. A compact arrangement would also minimize the cost of the equipment and improve flow distribution to the hydrocyclone inlets.
[0009] The inventor has realized that a related limitation of existing hydrocyclone assembly design is that of flow distribution of fluid into the individual hydrocyclones of an assembly where the hydrocyclones are disposed in parallel within a conventional hydrocyclone vessel. In this type of arrangement, exemplified in FIG. 1, the hydrocyclones 18 are all contained within a single vessel 12 . Fluid is injected into a chamber 28 of the vessel 12 via a single inlet nozzle 30 . As a result of differential pressure, the fluid passes from the chamber 28 into the inlets 31 of the individual hydrocyclones 18 . Using current designs, the inlets 31 of the individual hydrocyclones are all disposed at approximately the same longitudinal location within the chamber 28 . The concentration of fluid inlets 31 in the same location results in poor fluid distribution that may actually decrease the effectiveness of the hydrocyclone assembly 10 by limiting differential pressure in the area where the inlets 31 are concentrated. It would be desirable to provide improved flow distribution to the hydrocyclone inlets.
[0010] One variation of a prior art arrangement of hydrocyclones placed the hydrocyclones in vertically spaced apart layers, with the hydrocyclones of each layer being disposed in radial arranged arrays with common intake, overflow and underflow piping communicating with the hydrocyclones of the several layers. This arrangement saved the floor space area required for the hydrocyclones above the equipment floor while the intake, overflow and underflow piping was installed beneath the floor together with the necessary valves on each unit for adjusting pressures and for isolating individual hydrocyclones.
[0011] Alternative forms of modular hydrocyclone separator systems have been devised in an effort to overcome problems with the layered system. These new systems involve vertically disposed, suitably spaced intake, overflow and underflow headers. Individual hydrocyclones are connected to these headers and a positioned in generally vertical planes in substantially horizontal positions, one above the other. Thus, operator control of the system is facilitated and the operation of individual hydrocyclones can be observed.
[0012] Prior methods of arranging multiple hydrocyclones have provided only limited results in the goal of reducing the volume of space taken up by the hydrocyclones. U.S. Pat. No. 4,437,984 shows hydrocyclones arranged vertically, with the hydrocyclones parallel to each other. U.S. Pat. No. 4,163,719 shows hydrocyclones stacked in angled vertical arrays, where each hydrocyclone body is roughly parallel to other hydrocyclones in the same vertical array. U.S. Pat. No. 4,019,980 also shows hydrocyclones stacked in angled vertical arrays, where each hydrocyclone body is roughly parallel to other hydrocyclones in the same vertical array, and also shows multiple arrays sharing common input piping. U.S. Pat. No. 5,499,720 shows hydrocyclones arranged in a radial pattern, with the narrowing bodies of the hydrocyclones adjacent to each other.
[0013] It is desired to have hydrocyclones packaged as tightly together as possible so as to take up the minimum amount of space. For offshore platform and ship-based installations, volume of space is at a premium and greater efficiencies are desired for the use of a given volume of space.
[0014] Hydrocyclone separators are usually conical in shape, with a wide overflow end and a narrowed underflow end. Placing individual hydrocyclone separators parallel to each other requires that the distance between the center of any two hydrocyclones be at a minimum equal to the combined radii of the two hydrocyclones. Where the hydrocyclones may need to be removed for replacement or maintenance, additional spacing is required to allow for free movement of the hydrocyclones, or even for mounting elements. It is desired to reduce the amount of space between hydrocyclones to allow for more hydrocyclones to occupy a given space.
SUMMARY OF THE INVENTION
[0015] The present invention provides an improved arrangement of hydrocyclones, resulting in a greater density of hydrocyclones packaged in a given volume. One or more overflow extensions is secured to the overflow portions of one or more hydrocyclones to permit individual hydrocyclones to be placed into an axially staggered arrangement with respect to each other. By keeping the larger hydrocyclone heads from being directly adjacent that of a neighbor's, the maximum diameter of the hydrocyclones no longer becomes a limitation on the proximity of one hydrocyclone to another. In preferred embodiments described herein, the inlet section of one of a group of hydrocyclones is disposed to be adjacent either the separation portion of an adjacent hydrocyclone or an overflow extension, thereby permitting denser packaging and improved flow distribution.
[0016] In another aspect of the present invention, groups of axially staggered hydrocyclones are axially offset from and intermeshed with one another, permitting greater density in packaging. In a preferred embodiment, the groups of hydrocyclones are arranged into groups of three hydrocyclones each such that the axial ends of the individual hydrocyclones form a triangle, most preferably an equilateral triangle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] For detailed understanding of the invention, reference is made to the following detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings in which reference characters designate like or similar elements throughout the several figures of the drawings.
[0018] [0018]FIG. 1 is a side view of an exemplary prior art hydrocyclone assembly.
[0019] [0019]FIG. 2 is a side view of a currently preferred embodiment for a hydrocyclone assembly constructed in accordance with the present invention, showing three hydrocyclone separators.
[0020] [0020]FIG. 3 is a schematic end view of an exemplary layout for a packaging arrangement in accordance with the present invention showing three hydrocyclones that are axially staggered and axially offset.
[0021] [0021]FIGS. 4 and 5 are schematics depicting multiple triangular bundles of hydrocyclones being packaged to provide an intermeshed grouping of hydrocyclones.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] A hydrocyclone separation assembly includes a plurality of individual hydrocyclones. Referring first to FIG. 1, an exemplary prior art hydrocyclone separation assembly 10 is shown that includes an outer cylindrical vessel 12 that retains a pair of support members, or plates, 14 , 16 , proximate its axial ends that support several hydrocyclones 18 arranged in a substantially parallel relation with respect to one another. Opposite end portions of the hydrocyclones 18 are disposed through apertures 19 in the first and second support plates 14 , 16 .
[0023] Each hydrocyclone 18 comprises a single tubular body with an overflow (reject) section 20 , an inlet section 22 , a tapered separation chamber section 24 , and an underflow (tail pipe) section 26 . As is known in the art, a fluid or fluid/solid mixture is introduced under pressure into a chamber 28 defined within the outer vessel 12 via a single inlet (shown schematically as nozzle 30 ). The inlet 30 is typically a large diameter inlet that is located proximate the longitudinal middle of the vessel 12 and delivers fluid flow that is at least equal to the individual capacity of the hydrocyclones 18 multiplied times the number of hydrocyclones 18 . The fluid mixture then enters the individual inlet sections 22 of each individual hydrocyclone 18 via lateral inlet ports 31 . The hydrocyclones 18 separate the fluid mixture into constituent fluid components in a well known manner. The lighter fraction of fluid exits the overflow outlet 20 of the hydrocyclone 12 and then exits the vessel 12 via reject nozzle 33 . The heavier fluid fraction exits each hydrocyclone 12 through the underflow section 26 and exits the vessel 12 via underflow nozzle 35 .
[0024] It is noted that the inlet section 22 of each hydrocyclone 18 includes a substantially cylindrical chamber portion 32 , which presents the largest cross-sectional diameter “D” of any portion of the hydrocyclone 18 . In the prior assembly 10 depicted in FIG. 1, the inlet sections 22 of neighboring hydrocyclones 18 are positioned directly adjacent to one another such that the axial ends 34 of the underflow section 26 of each hydrocyclone 18 are substantially aligned in a plane 36 that is normal to the longitudinal axes of the hydrocyclones 18 . As a result of this positioning, it can be seen that minimum spacing between the hydrocyclones 18 is constrained by the diameter D of the inlet section 22 . A trunnion 38 is fixedly secured to the radial exterior of the underflow section 26 of each hydrocyclone 18 . The trunnions 38 provide an interference fit within the support plate 16 .
[0025] Referring now to FIG. 2, there is shown a portion of an exemplary hydrocyclone separator assembly 50 that is constructed in accordance with the present invention. A set of three hydrocyclones 18 a , 18 b , and 18 c are depicted, although it should be understood that in practice there is typically a greater number of hydrocyclones 18 . The hydrocyclones 18 a , 18 b , and 18 c are constructed in essentially the same manner as the hydrocyclones 18 described earlier. The second hydrocyclone 18 b is provided with an overflow extension 40 that extends between and interconnects the inlet portion 22 b with the support plate 14 . The third hydrocyclone 18 c is also provided with an overflow extension 42 that extends between and interconnects the inlet portion 22 c with the support plate 14 . The overflow extension 42 has a length that is greater than the length of the overflow extension 40 . Both the overflow extensions 40 and 42 are tubular members that permit fluid to flow from the overflow outlet 20 through the support member 14 and into an overflow receptacle (not shown) of a type known in the art. It is also noted that the overflow extensions 40 and 42 each have a diameter “d” that is less than the diameter D of the inlet section and preferably approximates the smaller diameter “d” of a portion of a separation section 26 . The underflow sections 26 a , 26 b , and 26 c are provided with slidable trunnions 44 that are moveable axially along the length of the underflow sections 26 a , 26 b , and 26 c . The trunnions 44 form a secure interference fit with the support plate 16 .
[0026] The axially staggered arrangement of the present invention has the effect of axially displacing the respective inlet sections 22 a , 22 b , and 22 c of the hydrocyclones 18 a , 18 b , and 18 c with respect to one another so that the inlet section of one hydrocyclone lies adjacent the separation chamber section 24 a , 24 b , 24 c of a neighboring hydrocyclone. Specifically, the inlet section 22 c of the third hydrocyclone 18 c lies adjacent the separation chamber section 24 b of the second hydrocyclone 18 b , while the inlet section 22 b of the second hydrocyclone 18 b lies adjacent the separation chamber section 24 a of the hydrocyclone 24 a . It should be understood that the packaging techniques and methods of the present invention may be applied to any model of hydrocyclone having an inlet/head section which is greater in diameter than the underflow portion. Examples include “K” hydrocyclone liners having a removable involute, as well as those hydrocyclone liner styles known within the industry as “Km,” “Kq,” and “Gm.”
[0027] Additionally, the presence of the overflow extensions 40 , 42 , and their reduced diameter (as compared to the inlet sections 22 ) accommodates neighboring inlet sections 22 . It can be seen from FIG. 2 that the inlet section 22 a of the hydrocyclone 18 a lies adjacent the overflow exntension 40 , and the inlet section 22 b of the hydrocyclone 18 b lies adjacent the overflow extension 42 . It is noted that, in this axially staggered packaging arrangement, the axial ends 34 of the underflow sections 26 a , 26 b , and 26 c do not lie in a plane that is normal to the axes of the hydrocyclones 18 , such as plane 36 depicted previously. Instead, the ends 34 are staggered.
[0028] The axially staggered arrangement also provides improved flow distribution within the vessel 12 of the hydrocyclone assembly 10 . The fluid inlets 31 of the hydrocyclones 18 a , 18 b , 18 c are axially spaced apart from one another, resulting in a higher effective differential pressure for each of the inlets 31 . As a result, flow distribution within the vessel 12 is improved.
[0029] It is preferred that the packaging of the hydrocyclones 18 a , 18 b , and 18 c be such that the inlet sections 22 a , 22 b , and 22 c be in contact with or in very close proximity to the respective adjacent separation chamber section 24 or overflow extension 40 or 42 . The hydrocyclones 18 a , 18 b , and 18 c may be aligned in a straight line, as FIG. 2 depicts. Alternatively, the hydrocyclones 18 a , 18 b , and 18 c may be displaced in a second direction (Z axis) to result in a further space savings as is described with respect to FIG. 3.
[0030] Referring now to FIG. 3, there is shown a schematic end-on view of three hydrocyclones 18 a , 18 b , and 18 c that are packaged in an arrangement wherein the three hydrocyclones are axially staggered, as described earlier with respect to FIG. 2, and further axially offset from one another. As used herein, the term “axially offset” means that the axes of the hydrocyclones 18 a , 18 b , and 18 c do not form a straight line and, instead, form a triangle, most preferably the equilateral triangle 46 depicted in FIG. 3. The letter “S,” to denote a “short” length, is used to label hydrocyclone 18 a , indicating that the overall length of that hydrocyclone is less than the length of the hydrocyclones 18 b and 18 c when considered with their attached overflow extensions 40 , 42 , respectively. The letters “M” denoting “medium” length and “L” denoting “long” length are used to label the hydrocyclones 18 b and 18 c , respectively.
[0031] In the preferred embodiment depicted in FIG. 3, the packaging is such that the outer diametrical surface of the inlet section 22 a of the first hydrocyclone 18 a contacts or is closely proximate to the overflow extension 40 associated with the second hydrocyclone 18 b and the overflow extension 42 associated with the third hydrocyclone 18 c . The outer diametrical surface of the inlet section 22 b of the second hydrocyclone 18 b contacts or is closely proximate to the separation chamber portion 24 a of the first hydrocyclone 18 a as well as the overflow extension 42 associated with the third hydrocyclone 18 c . The outer diametrical surface of the inlet portion 22 c of the third hydrocyclone 18 c contacts or is closely proximate to the separation sections 24 a and 24 b of the first and second hydrocyclones 18 a and 18 b , respectively. The three hydrocyclones 18 a , 18 b , 18 c are preferably maintained together into the triangular configuration shown in FIG. 3 by corresponding patterns of apertures 19 within the first and second support plates 14 , 16 . In other words, the apertures 19 are disposed in a triangular configuration within the respective support plates 14 , 16 and are of such spacing from one another that they retain the hydrocyclones 18 a , 18 b , and 18 c in the configuration depicted in FIG. 3. The triangular formation depicted in FIG. 3 results in a triangular bundle, generally indicated as 48 , in which the hydrocyclones 18 a , 18 b , 18 c are intermeshed with one another to reduce the interstitial space between the hydrocyclones, thereby further enhancing the ability to package the hydrocyclones 18 a , 18 b , 18 c densely within an assembly.
[0032] The triangular bundle 48 provides a basic building block that may be repeated within an assembly in order to maximize packaging of hydrocylones within a given volume or area. FIGS. 4 and 5 illustrate this. The exemplary hydrocyclone bundle 48 described above is packaged with other, like-constructed bundles 50 , 52 , 54 , 56 , and 58 . The spacing between the bundles 48 , 50 , 52 , 54 , 56 , and 58 is exaggerated in FIG. 4 for clarity. It should be understood that, in fact, these bundles are all placed either into contact with or in very close proximity to one another, as indicated that the arrows 60 . The neighboring bundles can then be intermeshed with one another in the same manner as the individual hydrocyclones 18 a , 18 b , and 18 c are. In other words, the “S” hydrocyclone 18 a from the bundle 48 intermeshes with the axially staggered “M” hydrocyclone 18 b from bundle 52 and “L” hydrocyclone 18 c from bundles 50 . It can be appreciated, then, that the advantages of the present invention may be realized in a three-dimensional manner. Where the advantages of axially staggering hydrocyclones is clearly shown in a two-dimensional array in FIGS. 2, 3 and 4 show that a greater density of hydrocyclones may also be achieved by implementing an axially offset relationship along a third dimension.
[0033] Those of skill in the art will recognize that numerous modifications and changes may be made to the exemplary designs and embodiments described herein and that the invention is limited only by the claims that follow and any equivalents thereof. | An arrangement of hydrocyclones, resulting in a greater density of hydrocyclones packaged in a given volume. One or more overflow extensions is secured to the overflow portions of one or more hydrocyclones to permit individual hydrocyclones to be placed into an axially staggered arrangement with respect to each other. By keeping the larger hydrocyclone heads from being directly adjacent that of a neighbor's, the maximum diameter of the hydrocyclones no longer becomes a limitation on the proximity of one hydrocyclone to another. The inlet section of one of a group of hydrocyclones is disposed to be adjacent either the separation portion of an adjacent hydrocyclone or an overflow extension, thereby permitting denser packaging. In another aspect, groups of axially staggered hydrocyclones are axially offset from and intermeshed with one another, permitting greater density in packaging. The groups of hydrocyclones are arranged into building blocks of three hydrocyclones each such that the axial ends of the individual hydrocyclones form a triangle, most preferably an equilateral triangle. | 1 |
FIELD OF THE INVENTION
The present invention relates to a system for the connnection between a photodetector and an optical fiber, and in particular for the alignment and assembly of an optical fiber with a photodetector in a hermetic package with a glass window and with a fiber leader.
BACKGROUND OF THE INVENTION
As is well-known, the success of an optical fiber transmission system used in communications is related to the availability of solid state sources and detectors. Such detectors must be efficient, reliable and inexpensive and may be of a type APD (avalance photodiode), typically assembled in a hermetic package without a fiber leader. The optical fiberphotodetector assembly must posses high sturdiness and quality.
It is known that the package tightness is indispensable for guaranteeing protection from pollution produced by chip contamination agents that, owning to the high input voltages of approximately 200 V necessary for getting the avalanche gain, would reduce greatly the component life.
The connection efficiency between the optical fiber and APD through the glass window is ordinarily quite high, as the APD construction technique allows one to get good performances with a useful photosensitive area having a diameter comprised between 250 and 600 mm, to which corresponds a maximum distance of the fiber without connection losses comprised between 0.49 and 1.35 mm.
The classic solutions for the connection of the fiber with a detector supplied with a glass window and without a lead are numerous but not free from drawbacks. One conventional and frequently used device (used by the applicant itself) is shown in schematic section view in the FIG. 1. It is formed of a substantially cylindrical bush (BU); its lower side and hole (PA) hold the APD that terminates on its upper side with the plate of the glass window (VE). The monofiber cable (CA) with insulation (G) penetrates for a substantial depth (H) into the upper cylindrical part of the bush (BU) and continues into the lower zone without insulation as an uncovered fiber (FO) to a depth (h).
Generally, positioned between the upper cylindrical part (BU') of the bush (BU) and the passage (PA) having a smaller diameter, is a truncated conical fitting (BU"). As the drawing shows, the fiber end (FO) is kept at a very small distance from the glass (VE). The cable (A) and its appendix (FO) are secured in the position shown by filling all the inner bush volume (BU) with resin (preferably opaque in the upper part and transparent in the lower part).
The alignment of the termination end of the fiber (FO) with the APD was typically made by means of micromovements of the fiber. Among the more important drawbacks of this type of assembly are the following:
the jacket (I) between the free lower fiber end (FO) and the lower surface of the glass (VE) holds a resin stratum that, in some conditions, damages and breaks the glass (VE);
the jacket (I) height between (VE) and (FO) is notoriously critical as the maximum coupling is obtained only at a precise position.
The adjustment of (I) is not easy in the illustrated prior art arrangement. If the free fiber end is pushed too much against (VE), the fiber is bent until its breakage; on the contrary, if it is positioned far from (VE), coupling efficiency is lost.
SUMMARY OF THE INVENTION
An object of the present invention is therefore to provide a system without the above-mentioned drawbacks which allows an efficient, sure and quick coupling between the optical fiber and the photodetector.
The system according to the invention for the alignment and the assembly of one optic fiber end with a photodetector in hermetic package form with glass window and without a fiber tail is comprised of the following. One fiber end is terminated by a optical fiber support member. A support plate is provided with two cylindrical concentric seats on opposite faces. These concentric seats communicate between themselves by a common hole. The hermetically sealed photodetector is introduced into one of these seats with the glass window in an internal position and aligned with the common hole; the free end of the optical fiber support member is introduced into the other seat, whereby the optical fiber is also aligned with the plate hole. Finally, the detector device and free optical fiber support member are fixed to their respective seats in the plate by synthetic catalyzed and possibly filled resins.
These and other features and advantages of the invention will become apparent in the following description of the preferred embodiment, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a prior art connection system.
FIGS. 2, 3, 4 are schematic partially sectioned views of an optical fiber terminal and, respectively, of two assemblies of this terminal with two slightly different plates.
FIGS. 3A and 4A are plan views of the plates for the assemblies of the FIGS. 3 and 4; and
FIGS. 3B and 4B are traverse sections of the plates shown in the FIGS. 3A and 4A.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the FIGS. 2 to 4B, the system of the present invention is assembled as follows:
(A) Set-up of the optic cable
In accordance with the invention, the optical cable (CA) to be assembled to the APD is terminated at its connection end with a optical fiber support member (1) shown in enlarged scale in FIG. 2). Optical fiber support member (1) is comprised of a body including (from top to bottom) a cylindrical section (2C), having height (H2C) and an inner diameter slightly larger than the external diameter (DC) optical cable insulation; a truncated conical part (3TC) having height (H3TC) and diameter decreasing from (D2C) (substantially equal to the sheath one) to the diameter (D4R) slightly larger than the diameter of the optical fiber (FO) (without insulation); a part (4R) having height (H4R) and inner diameter (D4R) slightly larger than the external diameter of the fiber (FO); a flanged lower part (5F) having height (H5F) and external diameter (D5F); and finally a recess (6SB) in the lower face (9) of the body (1) of the optical fiber support member having height (H6SB) and diameter (D6SB). The connection between the cable (CA) and the optical fiber support member is made as follows (see also FIGS. 3 and 4):
(1) the cylindrical body (2C) (and partially the truncated cone section 3TC also) of the optical fiber support member (1) is preferably filled with epoxy resin (e.g. of the EPOTEX 302 type);
(2) the peeled fiber end (FO) is introduced into the optical fiber support member (1) until the plastic external insulation (CA) rests on the ledge (20) of the truncated cone section (3TC); generally the free end of FO enters the recess (6SB);
(3) an epoxy resin, including alumina (e.g. 0.27-0.37 gr. of alumina per 1 gr. of resin), is prepared and a drop of it is introduced into the recess or slot (6SB) of the connector (1) around the fiber hole (FO) in the component side;
(4) the resin is polymerized, e.g. at room temperature for about 1 hour or at 60 C for about 15 minutes;
(5) when the polymerization is completed, an edge surface 9 of the cylindrical optical fiber support member is made by any conventional technique such as lapping.
FIGS. 3 and 4 show the polymerized resin stratum applied during the phase (1) that is indicated as (RI) and the resin drop is indicated as (RC).
(B) APD Bushing
(6) The first operation consists in carefully cleaning the glass (VE) of the APD, e.g. by isopropyl alcohol; for avoiding the halos produced by alcohol vaporization, the glass (VE) must be accurately dried;
(7) then the metallic package of the device (APD) is cleaned and a resin stratum of conductive silver paste is applied, which is shown in FIG. 3 as (RCC).
(8) the resin-sheathed photodetector device is introduced into the cylindrical support plate (FIGS. 3, 3A, or 4, 4A) that is substantially a plate (S) having an upper seat (SF) for holding the assembled optical fiber support member (SC) of FIG. 2 and a lower seat (SI) (40) for holding the photodetector device (DF).
Preferably, the upper and lower seats (SF) and (SI) both have a cylindrical shape and short cavities. The support (S) also has two symmetrical fastening holes (50) and (50') and a smaller threaded hole (51).
The upper seat (SF) (30) has a step shape (with either a single step (30') (FIGS. 3, 3A and 3B) or a double step (30 and 30") (FIGS. 4, 4A and 4B). The step seat (30) is thoroughly degreased before introducing the hermetic device (DF) into it. The glass (VE) of device (DF) must be in alignment with the plate (S) reference plane. For facilitating this alignment, a ground punch, placed in a ledge on the reference plane, may be used.
All the above-described parts are placed into an oven e.g. at 60° for approximately 18 hours. When the polymerization is complete, an epoxy resin is applied on the bottom (40) of the plate (S) for improving the mechanical seal between APD (DF) and support (S). A light resin stratum (41) (indicated with dots in FIG. 3) is formed. This operation also can be made in massproduction on the devices to be assembled.
(C) Assembly between APD and the optical fiber
The lower face of the flanged optical fiber support member (SC), having the drop of (RC) introduced into its recess (6SB), is inserted into the seat (30) of the support (S) plate that, as FIGS. 3 and 4 show, is much wider and taller than the flange (5F) of optical fiber support member (SC). The optic output power of the fiber (FO) placed into the cylinder (1) may be tested by use of a proper adapter for the photodetector (not shown, as it is wellknown).
After having placed the APD device into the proper seat (DI) of the support plate (S), the flanged cylindrical optical fiber support member is placed into a clamp that is aligned to assure that the axis of optical fiber support member (1) and the plate reference plane are precisely perpendicular.
The lapped cylinder (9) surface is placed against the ledge of the plate reference plane and, with movements solely in the direction transverse to the fiber axis, it is possible to optimize the alignment between the active part of the device (DF) and the fiber (FO).
The plate (S) and the cylindrical optical fiber support member (SC) are secured together by carbon-filled epoxy resin, containing, e.g., 0.35 gr. of carbon for 1 gr. of resin (RA).
An advantage of this technique over the prior art technique is that the optical fiber is introduced into the rigid body of the optical fiber support member (SC), secured by resin, and placed on a ledge on the plate (1) reference plane, thereby eliminating the necessity of correctly positioning the optical fiber in the vertical direction height.
Furthermore, the cylindrical optical fiber support member (1) with the introduced fiber (FO) is lapped, avoiding thereby the prior technique of cutting the peeled fiber, which prior technique must be carefully controlled and often requires remaking due to the delicacy of the non-protected fiber.
According to a further advantageous feature of the invention, an air stratum (AR) is applied between the fiber end (FO) in the recess (6SB) and the glass (VE) of the device in place of a resin stratum as shown in the jacket (I) of FIG. 1. The former technique disadvantageously generates a Fresnel loss in the optic connection of approximately 0.4 dB. The air stratum (AR) is minimum, therefore it is barely noticeable in FIGS. 3 and 4.
A system with components assembled conventionally as shown in FIG. 1 was compared to the described system of the present invention by testing the respective devices in environmental conditions that simulate the worst possible conditions. The tests showed that devices assembled in accordance with the conventional process often suffered breakdowns, due to the mechanical stress generated by the resin on the window (VE) of the APD.
For determining which of the devices manufactured by the prior art technique components are defective in this respect, it is necessary to submit the entire production run to a burn-in that will expose any component degradation. This burn-in involves considerable industrial costs. Therefore, it is surely advantageous and preferable to use the process of the present invention that does not result in devices having the above mentioned problems.
The sole drawback of the present invention is a loss amounting of approximately 0.4 dB, due to the reflection in the interface between glass and fiber, the air and the glass of the APD window.
The process of the present invention is suitable for an industrial production, as it advantageously requires no further screening after the assembly. The assembly has a good optic efficiency and perfect mechanical performance using a wellprotected fiber. Further, the present invention allows maximum flexibility in the selection of the connector and the photodiode type to be used.
Although the present invention has been described in connection with a preferred embodiment thereof, many other variations and modifications will now become apparent to those skilled in the art without departing from the scope of the invention. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims. | A system for the alignment and assembly of optical fibers to photodetectors in a hermetic package with a glass window and without fiber tail. One end of an optical fiber is terminated with an optical fiber support member. A support plate is provided with two concentric seats on opposite faces of the plate. A photodetector is inserted into one of the seats, and the connector part is inserted into the other seat. Synthetic resins are used to secure the photodetector and connector part to their respective plate seats. | 7 |
This application claims priority under 35 U.S.C. §§119 and/or 365 to 0003549-3 filed in Sweden on Oct. 2, 2000; the entire content of which is hereby incorporated by reference.
TECHNICAL FIELD OF THE INVENTION
The present invention generally relates to field of sampling, and more specifically, to methods and apparatus for reconstruction of nonuniformly sampled bandlimited signals, to methods and apparatus for compensation of time skew in time-interleaved analog-to-digital converters (ADCs), and to a computer program product for performing said methods of reconstruction.
DESCRIPTION OF RELATED ART AND BACKGROUND OF THE INVENTION
In uniform sampling, a sequence x(n) is obtained from an analog signal x a (t) by sampling the latter equidistantly at t=nT, −∞<n<∞, i.e., x(n)=x a (nT), T being the sampling period, as illustrated in FIG. 1 a . In this case, the time between two consecutive sampling instances is always T. In nonuniform sampling, on the other hand, the time between two consecutive sample instances is dependent on the sampling instances. The present invention deals with the situation where the samples can be separated into N subsequences x k (m), k=0, 1, . . . , N−1, where x k (m) is obtained by sampling x a (t) with the sampling rate 1/(MT) at t=nMT+t k , i.e., x k (m)=x a (nMT+t k ), M being a positive integer. This sampling scheme is illustrated in FIG. 1 b for N=2 and M=2. Such nonuniformly sampled signals occur in, e.g., time-interleaved analog-to-digital converters (ADCs) due to time skew errors.
The question that arises is how to form a new sequence y(n) from x k (m) such that y(n) is either exactly or approximately (in some sense) equal to x(n). For conventional time-interleaved ADCs, N=M and, ideally, t k =kT. In this case, y(n)=x(n) is obtained by simply interleaving x k (m). However, in practice, t k is not exactly equal to kT due to time skew errors which introduces aliasing components into Y(e jωT ), Y(e jωT ) being the Fourier transform of y(n). This means that y(n)≠x(n), and thus the information in y(n) is no longer the same as that in x(n).
It should be noted that it is well known that, if the t k 's are distinct such that all samples are separated in time, then x a (t) is uniquely determined by the samples in the x k (m)'s. It is also well known how to retain x a (t) from the x k (m)'s using analog interpolation functions. However, these functions are not easily, if at all possible, achievable in practical implementations, which thus call for other solutions.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a method and an apparatus, respectively, for reconstruction of a nonuniformly sampled bandlimited analog signal x a (t), said nonuniformly sampled signal comprising N subsequences x k (m), k=0, 1, . . . , N−1, N≧2, obtained through sampling at a sampling rate of 1/(MT) according to x k (m)=x a (nMT+t k ), where M is a positive integer, and t k =kMT/N+Δt k , Δt k being different from zero, which are capable of forming a new sequence y(n) from said N subsequences x k (m) such that y(n) at least contains the same information as x(n)=x a (nT), i.e. x a (t) sampled with a sampling rate of 1/T, in a frequency region lower than ω 0 (and possibly including ω 0 ), ω 0 being a predetermined limit frequency.
A further object of the present invention is to provide such method and apparatus, respectively, which are efficient, fast, simple, and of low cost.
Still a further object of the present invention is to provide such method and apparatus, respectively, which are capable of reducing noise such as e.g. quantization noise.
Those objects among others are attained by a method and an apparatus, respectively, which perform the steps of:
(i) upsampling each of the N subsequences x k (m), k=0, 1, . . . , N−1, by the factor M;
(ii) filtering each of the upsampled N subsequences x k (m), k=0, 1, . . . , N−1, by a respective digital filter; and
(iii) adding the N digitally filtered subsequences to form y(n).
Preferably, the respective digital filter is a fractional delay filter and has a frequency response G k =a k e (−jωsT) , k=0, 1, . . . , N−1, in the frequency band |ωT|≦ω 0 T, a k being a constant and s being different from an integer, and particularly s equals d+t k , d being an integer.
If ω 0 T is a fixed value less than π, such that the original analog signal comprises frequency components of a higher frequency than ω 0 , regional perfect reconstruction is achieved, i.e. y(n) contains the same information as x(n)=x a (nT), i.e. x a (t) sampled with a sampling rate of 1/T, only in a frequency region |ω|≦ω 0 . Regionally perfect reconstruction is of particular interest in oversampled systems where the lower frequency components carry the essential information, whereas the higher frequency components contain undesired components (e.g., noise) to be removed by digital and/or analog filters.
Here, the fractional delay filters have a frequency response G k =a k A k (e jωT ), k=0, 1, . . . , N−1, in the frequency band ω 0 T<|ωT|≦π, where A k (e jωT ) is an arbitrary complex function.
If on the other hand ω 0 does include all frequency components of the original analog signal (i.e. ω 0 T includes all frequencies up to π) perfect reconstruction is achieved, i.e. y(n) is identical with x(n).
In either case two different situations arise: (1) 2K 0 +1=N and (2) 2K 0 +1<N, wherein K 0 is given by K 0 = ⌈ M ( ω 0 T + ω 1 T ) 2 π ⌉ - 1
for regionally perfect reconstruction, wherein ┌x┐ should be read as the smallest integer larger than or equal to x and [−ω 1 , ω 1 ] being the frequency band wherein said bandlimited analog signal x a (t) is found, respectively, and by
K 0 =M −1
for perfect reconstruction.
In situation (1) the a k 's are calculated as
a=B
−1
c,
a being the a k 's in vector form given by
a=[a 0 a 1 . . . a N−1 ] T ,
B −1 being the inverse of B as given by B = [ u 0 - K 0 u 1 - K 0 ⋯ u N - 1 - K 0 u 0 - ( K 0 - 1 ) u 1 - ( K 0 - 1 ) ⋯ u N - 1 - ( K 0 - 1 ) ⋮ ⋮ ⋮ u 0 K 0 u 1 K 0 ⋯ u N - 1 K 0 ] ,
wherein u k = - j 2 π MT t k ,
and c being
c=[c 0 c 1 . . . c 2K 0 ] T ,
wherein c k = { M , k = K 0 0 , k = 0 , 1 , … , 2 K 0 , k ≠ K 0 .
In situation (2) the a k 's are calculated as
a={circumflex over (B)}
−1
ĉ,
a being defined as
a=[a u a fix ] T
wherein a u and a fix contain (2K 0 +1) unknown a k 's and L=N−2K 0 −1 fixed constant a k 's, {circumflex over (B)} −1 being the inverse of {circumflex over (B)} as given by B ^ = [ B S ] ,
wherein B is given by B = [ u 0 - K 0 u 1 - K 0 ⋯ u N - 1 - K 0 u 0 - ( K 0 - 1 ) u 1 - ( K 0 - 1 ) ⋯ u N - 1 - ( K 0 - 1 ) ⋮ ⋮ ⋮ u 0 K 0 u 1 K 0 ⋯ u N - 1 K 0 ] ,
wherein u k = - j 2 π MT t k ,
S is given by
S=[S z S d ],
wherein S z = [ 0 0 ⋯ 0 0 0 ⋯ 0 ⋮ ⋮ ⋮ 0 0 ⋯ 0 ]
and
S d =diag[1 1 . . . 1],
and
ĉ being
ĉ=[c a fix ] T ,
wherein
c is given by
c=[c 0 c 1 . . . c 2k 0 ] T ,
wherein c k = { M , k = K 0 0 , k = 0 , 1 , … , 2 K 0 , k ≠ K 0 .
Thus L a k 's can be arbitrarily chosen. Preferably they are chosen to be zero in which case the corresponding channel is removed or to be M/N in which case any quantization noise can be minimized.
Further objects of the invention are to provide a method for compensation of time skew in a time-interleaved analog-to-digital converter (ADC) system comprising a plurality of analog-to-digital converters (ADCs), and to provide the ADC system itself.
Thus, such method and ADC system are provided comprising the respective method and apparatus as described above, wherein each of the N subsequences x k (m), k=0, 1, . . . , N−1, N≧2 is sampled by a respective one of the analog-to-digital converters.
Yet a further object of the present invention is to provide a computer program product for reconstruction of a nonuniformly sampled bandlimited analog signal.
Such object is attained by a computer program product loadable into the internal memory of a digital signal processing apparatus, comprising software code portions for performing any of the methods as depicted above when said product is run on said apparatus.
An advantage of the present invention is that a fully or partly reconstructed digital signal may be produced without the need of applying very complex and hardly implementable analog interpolation functions.
Further characteristics of the invention and advantages thereof will be evident from the following detailed description of embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description of preferred embodiments of the present invention given hereinbelow and the accompanying FIGS. 1-6, which are given by way of illustration only, and thus are not limitative of the present invention.
FIG. 1 a illustrates schematically uniform sampling, wherein a sequence x(n) is obtained from an analog signal x a (t) by sampling the latter equidistantly at t=nT, −∞<n<∞, i.e., x(n)=x a (nT); and FIG. 1 b illustrates schematically nonuniform sampling, wherein samples are separated into two subsequences x k (m), k=0, 1 where x k (m) is obtained by sampling x a (t) with the sampling rate 1/(2T) at t=n2T+t k , i.e., x k (m)=x a (n2T+t k ).
FIG. 2 illustrates schematically a uniform sampler and quantizer.
FIG. 3 illustrates schematically an upsampler.
FIG. 4 illustrates schematically a hybrid analog/digital filter bank ADC system.
FIG. 5 illustrates schematically an analysis filter bank system for producing x k (m), k 0, 1, . . . , N−1, x k (m) being N subsequences obtained through sampling of x a (t) at the time instances t=nMT+t k .
FIG. 6 illustrates schematically a polyphase representation of the upsampling and synthesis bank in the system of FIG. 4 .
DETAILED DESCRIPTION OF EMBODIMENTS
In the following description, for purposes of explanation and not limitation, specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced in other versions that depart from these specific details. In other instances, detailed descriptions of well-known methods and apparatuses are omitted so as not to obscure the description of the present invention with unnecessary details.
This invention considers the problem of reconstructing nonuniformly sampled bandlimited signals. Such problem arises in, e.g., time-interleaved analog-to-digital converters (ADCs) due to time skew errors. To be precise, we deal with the following situation. Given N subsequences x k (m), k=0, 1, . . . , N−1, obtained through sampling of a bandlimited analog signal x a (t) with a sampling rate of 1/(MT) according to x k (m)=x a (nMT+t k ). How to form a new sequence y(n) from x k (m) such that y(n) is either exactly or approximately (in some sense) equal to x(n)=x a (nT), i.e., x a (t) sampled with a sampling rate of 1/T. To this end, we propose in this patent the use of an N-channel digital synthesis filter bank. The overall system can be viewed as a generalization of the conventional time-interleaved ADCs, to which the former reduces as a special case. We show that the proposed system, with proper ideal synthesis filters, can achieve y(n)=x(n). These synthesis filters are however not suitable to be approximated by practical digital filters. Therefore, we also consider the case in which y(n)≠x(n) but where y(n) and x(n) contain the same information in a lower frequency region. We show that the overall system can achieve Y(e jωT )=X(e jωT ) for |ωT|≦ω 0 T, Y(e jωT ) and X(e jωT ) being the Fourier transforms of x(n) and y(n), respectively, and ω 0 being a predetermined limit frequency, again with proper ideal synthesis filters, which in this case can be approximated by practical digital filters. This scheme is useful for (slightly) oversampled ADC systems where aliasing into the frequency band ω 0 T<|ωT|≦π can be tolerated. The ideal synthesis filters are allpass filters with, in general, different gain constants. We analyze the effects of using practical filters approximating the ideal ones.
The outline of the remaining parts of this description is as follows. Firstly, uniform sampling, upsampling, and hybrid analog/digital filter banks, the latter of which is convenient to use when analyzing nonuniformly sampled systems, are briefly recapitulated. The following section deals with nonuniform sampling and reconstruction. Thereafter, time-interleaved ADCs and their generalizations are considered. The subsequent section is concerned with error analysis and quantization noise, respectively. Finally, a list of equations (eqs.) is given, said equations being referred to in the above said sections.
Uniform Sampling, Upsampling, and Filter Banks
Uniform sampling and quantization are represented by the uniform sampler and quantizer in FIG. 2 . Ignoring the quantization, the output sequence x(n) is obtained by sampling the analog input signal x a (t) uniformly at the time instances nT, for all n, see eq. (1) in the list of equations at the end of this description. Here, T is the sampling period and f sample =1/T is the sampling frequency. The Fourier transforms of x(n) and x a (t) are related according to Poisson's summation formula, see eq. (2).
The upsampler in FIG. 3 is used to increase the sampling frequency by a factor of M. The sampling period and sampling frequency associated with the lower rate, denoted here by T 1 and f sample,1 , respectively, are obviously related to T and f sample as in eq. (3). The output sequence y(n) is given by eq. (4) and the Fourier transforms of y(n) and x(m) are related to each other as in eq. (5).
Consider the system in FIG. 4, which we refer to as a hybrid analog/digital filter bank or filter bank ADC. This system makes use of an analog analysis filter bank, uniform samplers and quantizers, and a digital synthesis filter bank. The sampling and quantization take place at the output of the analysis filters with a sampling frequency of 1/T=f sample /M, since T 1 =MT. In the filter bank ADC, both the sampling and quantizations are thus performed at the low sampling rate f sample /M.
Ignoring the quantizations in the system of FIG. 4, the Fourier transform of the output sequence y(n) is easily obtained with the aid of the above relations, see eq. (6) wherein X k (e jMωT ) is given by eq. (7). Equation (6) can be rewritten as eq. (8) where V p (jω) is given by eq. (9).
Consider the systems in FIGS. 2 and 4 with X(e jωT ) and Y(e jωT ) as given by Eqs. (2) and (8), respectively. Recall that the spectrum of a sampled signal always is periodic with a period of 2π (2π-periodic). Thus, X(e jωT ) is apparently 2π-periodic. This holds true also for Y(e jωT ) as long as all G k (e jωT ) are 2π-periodic. Thus, it suffices to consider X(e jωT ) and Y(e jωT ) in the interval −π≦ωT≦π. We will now treat two different types of reconstruction.
Perfect reconstruction: The system in FIG. 4 has perfect reconstruction (PR) if Eq. (10) prevails for some non-zero constant c and integer constant d. In the time-domain we have in the PR case y(n)=cx(n−d). That is, with c=1, y(n) is simply a shifted version of x(n). From Eqs. (2), (8), and (10), we see that PR is obtained if Eq. (11) prevails for −∞≦r≦∞.
Regionally perfect reconstruction: Let x(n) and y(n) be separated as given by eq. (12) with corresponding Fourier transforms given by eqs. (13) and (14) where ω 0 T<π. The system in FIG. 4 has regionally perfect reconstruction (RPR) if eq. (15) or, equivalently, eq. (16) prevails for some non-zero constant c and integer constant d. In the time-domain we have in the RPR case y low (n)=cx low (n−d). That is, with c=1, y low (n) is simply a shifted version of x low (n). However, y(n) is not a shifted version of x(n), i.e., y(n)≠cx(n−d). From Eqs. (2), (8), and (16), we see that RPR is obtained if eq. (17) is fulfilled for −∞≦r≦∞. Regionally perfect reconstruction systems are of interest in oversampled systems where x low (n) carries the essential information, whereas x high (n) contains undesired components (e.g., noise) to be removed by digital and/or analog filters.
Bandlimited Cases: When X a (jω) is bandlimited, only a finite number of terms in the summations of eqs. (2) and (8) need to be handled in the interval −π≦ωT≦π. We consider two different cases.
Case A (PR): Let X a (t) be bandlimited according to eq. (18). In this case, the Nyquist criterion for sampling with an effective sampling frequency of 1/T without aliasing is fulfilled. Thus, x a (t) can be retained if aliasing into the band −π≦ωT≦π is avoided.
Consider first x(n) in FIG. 2 . From eq. (2), it is obvious that we have no aliasing in the region −π≦ωT≦π when X a (jω) is bandlimited according to eq. (18). Consider next y(n) in FIG. 4 . In the region −π≦ωT≦π, with X a (jω) being bandlimited according to eq. (18), it is easy to verify that we only need to consider 2K 0 +1 terms in eq. (8), for p=−K 0 , −(K 0 −1), . . . , K 0 , with K 0 given by eq. (19).
PR is now obtained if eq. (20) prevails, where K 0 is given by eq. (19). In this case, x a (t) can thus be retained from x(n) as well as y(n) provided that the system in FIG. 4 has PR.
Case B (RPR): Let X a (t) be bandlimited according to eq. (21) and separated according to eq. (22) with the corresponding Fourier transforms given by eqs. (23), (24), and (25).
In this case, x a (t) can not be retained but x a,low (t) can be retained as long as aliasing into the band −ω 0 T≦ωT≦ω 0 T is avoided.
Consider first x(n) in FIG. 2 . In the region −π≦ωT≦π, with X a (jω) being bandlimited according to Eqs. (21) and (25), it is obvious that we only need to consider 3 terms in eq. (2), for r=−1, 0, 1. Further, in the region −ω 0 T≦ωT≦ω 0 T, with ω 0 being given by eq. (25), it is easy to verify that we only need to consider one term, for r=0. That is, aliasing into this band is automatically avoided. Consider next y(n) in FIG. 4 . In the region −π≦ωT≦π, with X a (jω) being bandlimited according to Eqs. (21) and (25), it is easy to verify that we only need to consider 2K 0 +1 terms in eq. (8), for p=−K 0 , −(K 0 −1), . . . , K 0 , with K 0 being given by eq. (26), where ┌x┐ stands for the smallest integer larger than or equal to x. Further, in the region −ω 0 T≦ωT≦ω 0 T, with ω 0 being given by eq. (25), it is readily verified that we only need to consider 2K 0 +1 terms in eq. (8), for p=−K 0 , −(K 0 −1), . . . , K 0 , where K 0 is given by eq. (27).
RPR is now obtained if eq. (28) is fulfilled, wherein K 0 is given by eq. (27) and A(jω) is some arbitrary function. In this case, X a,low (t) can thus be retained from x(n) as well as y(n) provided that the system in FIG. 4 has RPR.
Nonuniform Sampling and Reconstruction
Let x k (m), k=0, 1, . . . , N−1, be N subsequences obtained through sampling of x a (t) at the time instances t=nMT+t k , i.e. as given by eq. (29). For M=N=2, x a (t) is sampled according to FIG. 1 b.
The subsequences x k (m) can be obtained by sampling the output signals from the analysis filters in FIG. 4 if these filters are selected according to eq. (30). The analysis filter bank is in this case as shown in FIG. 5 .
Combining Eqs. (9) and (30) gives us eq. (31).
Next, it is shown how to choose the synthesis filters in the bandlimited cases A and B (see previous section) so that PR and RPR, respectively, are obtained.
Case A (PR case): In this case X a (t) is bandlimited according to eq. (18). Let G k (e jωT ) be 2π-periodic filters given by eq. (32). From eqs. (31) and (32), eq. (33) is obtained. For PR it is required that V p (jω) as given by eq. (33) fulfils eq. (20). That is, PR is obtained if eq. (34) is fulfilled.
Case B (RPR case): In this case X a (t) is bandlimited according to eq. (21). Let G k (e jωT ) be 2π-periodic filters given by eq. (35), where A k (e jωT ) are some arbitrary complex functions. From eqs. (31) and (35) we obtain eq. (36), where A(jω) is given by eq. (37).
For RPR it is required that V p (jω) as given by eq. (36) fulfils eq. (28). That is, RPR is obtained if, again eq. (34) is satisfied.
How to compute the a k 's is next considered. For both PR and RPR (Cases A and B), eq. (34) must be fulfilled. This equation can be written in matrix form as eq. (38), where B is a (2K 0 +1)×N matrix according to eq. (39), wherein the u k 's are given by eq. (40). Further, a is a column vector with N elements and c is a column vector with 2K 0 +1 elements according to eqs. (41) and (42), respectively, where T stands for the transpose (without complex conjugate). The a k 's are the unknowns whereas the c k 's are given in accordance with eq. (43).
Eq. (38) is a linear system of2K 0 +1 equations with N unknown parameters a k . Hence, eq. (38) can be solved if 2K 0 +1≦N. We distinguish two different cases.
Case 1: 2K 0 +1=N. In this case, the number of unknowns equals the number of equations. The a k 's can in this case be uniquely determined under the conditions stated by the following theorem.
Theorem 1: If B and c are as given by eqs. (39) and (42), respectively, 2K 0 +1=N, and t k ≠t m +MTr, k≠m, rεZ, then there exists a unique a satisfying eq. (38), and thereby also unique a k 's satisfying eq. (34). Further, all the a k 's in a are real-valued constants.
Proof: We first prove that there exists a unique solution. Since 2K 0 +1=N, B is a square N×N matrix. If B is nonsingular, then a is uniquely determined by eq. (44), where B −1 is the inverse of B. It thus suffices to show that B is nonsingular under the stated conditions. To this end, we first observe that B as given by eq. (39) can be written as in eq. (45), where A is given by eq. (46) and C is a diagonal matrix according to eq. (47).
The matrix A is a Vandermonde matrix. The necessary and sufficient condition for nonsingularity of A is therefore that the u k 's are distinct, i.e., U k ≠u m , k≠m, which is the same condition as t k ≠t m +MTr, k≠m, rεZ, due to eq. (40). Further, since the determinant of B is det B=det A det C, and |det C|=1, we obtain the relations as given in eq. (48). That is, B is nonsingular if and only if A is nonsingular. This proves that B is nonsingular and a unique solution a always exists under the stated conditions.
To prove that the a k 's in a are real-valued constants we proceed as follows. Assume that we have the unique values a k that satisfy eq. (34). Using eq. (40), eq. (34) can equivalently be written as eq. (49), where x* stands for the complex conjugate of x. From eq. (49) we get eq. (50). This shows that the values a k * satisfy eq. (34) as well. However, since a k are unique, it follows that they must be real-valued.
Case 2: 2K 0 +1<N. In this case, the number of unknowns exceeds the number of equations. We can therefore impose L=N−2K 0 −1 additional linear constraints among the a k 's and still satisfy eq. (34). Here, we restrict ourselves to the case in which the L a k 's for k=N−L+1, N−L+2, . . . , N, are fixed to some constants. This case covers the conventional time-interleaved ADCs with an even number of channels. Since L a k 's are free we could of course set them to zero in the case of which the corresponding channels would be removed. In that sense, there is no need to consider the cases having an even number of channels. However, as we shall see below, it may be worth considering these cases in order to reduce the quantization noise at the output of the overall system.
The system of linear equations to be solved can here be written in matrix form as eq. (51) with {circumflex over (B)} being an N×N matrix, and a and ĉ being column vectors with N elements, according to eqs. (52), (53) and (54), respectively, where B is the (2K 0 +1)×(2K 0 +1) matrix as given by eq. (39), a u and a fix contain the (2K 0 +1) unknowns and L fixed constants of a, respectively, c is the column vector with (2K 0 +1) elements as given by eq. (43), S is an L×N matrix given by eq. (55), where S z is an L×(2K 0 +1) null matrix given by eq. (56), and S d is a L×L diagonal matrix where the diagonal elements are equal to one, see eq. (57).
As in Case 1, the a k 's can in Case 2 be uniquely determined under the conditions stated by the following theorem.
Theorem 2: If {circumflex over (B)} and ĉ are as given by eqs. (52) and (54), respectively, a fix in eq. (53) contains L real fixed constants, 2K 0 +1<N, and t k ≠t m +MTr, k≠m, rεZ, then there exists a unique a satisfying eq. (51), and thereby also unique a k 's satisfying eq. (34). Further, all the a k 's in a are real-valued constants.
Proof: The proof follows that of Theorem 1. To prove the existence and uniqueness, it thus suffices to show that {circumflex over (B)} is nonsingular under the stated conditions since a then is uniquely determined by eq. (58).
To prove nonsingularity of {circumflex over (B)}, we observe that its determinant is given by eq. (59), where {tilde over (B)} is a (2K 0 +1)×(2K 0 +1) submatrix obtained from B by deleting L columns for k=N−L+1, N−L+2, . . . , N, i.e. as given in eq. (60). We know from the proof of Theorem 1 that det {tilde over (B)}≠0 and thus det {circumflex over (B)}≠0 under the stated conditions. This proves that {circumflex over (B)} is nonsingular and a unique solution always exists. The proof that the a k 's in a are real-valued is done in the same manner as that of Theorem 1.
Time-interleaved ADCs and Their Generalizations
This section considers conventional time-interleaved ADCs and their generalizations. Consider first the case where N=M with t k being given by eqs. (61) and (62).
Further, let the synthesis filters G k (e jωT ) be given by eq. (32) with a k =1, k=0, 1, . . . , M−1, c=1, and d=0, i.e., as in eq. (63). From eqs. (31) and (63) we obtain eq. (64).
Thus, PR is obtained. In this case we have a conventional time-interleaved ADC. The output sequence y(n) is here obtained by interleaving the x k (m)'s.
In practice, Δt k will however no longer be exactly zero. If Δt k are known, the a k 's can be computed according to eq. (44) if N is odd and 2K 0 +1=N, or according to eq. (58) if 2K 0 +1<N. In this case, PR can not be achieved since N=M and PR requires that K 0 =M−1. Thus, neither 2K 0 +1=N nor 2K 0 +1 <N can be fulfilled. RPR can, on the other hand, be obtained. For this case, the following question arises: given N=M and K 0 , what is the maximum value of ω 0 T we can allow and still obtain RPR? It is readily established that to achieve RPR we must fulfill eq. (65). If 2K 0 +1=N we get eq. (66).
Consider next the case where N≠M with t k being given by eqs. (67) and (68). Further, let the synthesis filters G k (e jωT ) be given by eq. (32) with a k =M/N, k=0, 1, . . . , N−1, c=1, and d=0, i.e., as in eq. (69). From eqs. (31) and (69) we obtain eq. (70).
Thus, PR is obtained. In this case we have a system that can be viewed as a generalization of the time-interleaved ADCs. However, in this case we can no longer obtain the output sequence by interleaving the x k (m)'s.
Again, Δt k will in practice no longer be exactly zero. If Δt k are known, the a k 's can be computed according to eq. (44) if N is odd and 2K 0 +1=N, or according to eq. (58) if 2K 0 +1<N. As opposed to the M-channel case, we can here in the N-channel case achieve both PR and RPR by selecting K 0 according to eqs. (19) and (27), respectively, and of course choosing N so that 2K 0 +1<N. To achieve RPR, for given M and K 0 , ω 0 T must again satisfy eq. (65). If 2K 0 +1=N we get eq. (71). Hence, by increasing the number of channels we obtain RPR over a wider frequency region.
Error and Noise Analysis
Next an error analysis is provided. More precisely, we derive bounds on the errors in a and c, when B and a are replaced with B+ΔB and a+Δa, respectively. The errors in a are of interest as far as the quantization noise is concerned, as will become clear in the next section. The errors in c tell us how close to the ideal synthesis filters any practical filters must be in order to meet some prescribed allowable errors in c.
We will make use of the L ∞ -norms as defined by eq. (72) for an N×1 (1×N) vector x with elements x i , and as defined by eq. (73) for an N×N matrix X with elements x ik .
Errors in a: Consider first Case 1 with 2K 0 +1=N. Assume first that we have Ba=c for t k =d k T and a k . Assume next that t k =d k T and a k are replaced with t k =d k T+Δt k and a k +Δa k , respectively, whereas c is kept fixed. This amounts to eq. (74). The matrix ΔB is an N×N matrix according to eq. (75), where Δb pk and Δt pk are given by eqs. (76) and (77), respectively.
Now, if eq. (78) is satisfied then it can be shown that eq. (79) holds. From eqs. (75)-(77) we get eq. (80).
We have B=AC and consequently B −1 =C −1 A −1 . Further, since A is here a DFT matrix, its inverse A −1 is an IDFT matrix; hence ∥A −1 ∥ ∞ =1. We also have ∥C −1 ∥ ∞ =1 because C −1 apparently is a diagonal matrix with diagonal elements u k K 0 where u k are given by eq. (40). We thus have eq. (81), which, together with eq. (80), results in eq. (82). By using eqs. (79)-(82), and assuming ∥ΔB∥ ∞ ∥B −1 ∥ ∞ <<1, we finally obtain eq. (83).
Consider next Case 2 with 2K 0 +1<N. This case is somewhat more difficult than Case 1 since we generally can not express {circumflex over (B)} as a product between a DFT matrix and a diagonal matrix. However, if we restrict ourselves to the time-interleaved ADCs and their generalizations, it is readily shown that we can rewrite eq. (51) as eq. (84), where B′ is an N×N matrix according to eq. (85) with u k being given by eq. (40), and c′ is a column vector with N elements c k according to eq. (86)
Clearly, we can express B′ as a product between a DFT matrix and a diagonal matrix. We will therefore end up with the same result as in Case 1, i.e., the bound in eq. (83).
Errors in c: Assume that we have Ba=c for t k =d k T and a k . Assume now that t k =d k T and a k are replaced with t k =d k T+Δt pk and a k +Δa k , respectively. This amounts to eq. (87) from which we get eq. (88). In turn, from eq. (88) we obtain eq. (89). Using eqs. (39) and (75)-(77) we finally get eq. (90), which is useful in the design of the synthesis filters G k (z)
Recall from above that the ideal filters should have the frequency responses a k e −jwt k over the frequency range of interest [if c=1 and d=0 in eqs. (32) and (35)]. In practice, G k (z) can of course only approximate the ideal responses. We can express the frequency responses of G k (z) as eq. (91), where Δa k (ωT) and Δt pk (ωT) are the deviations from the ideal magnitude and phase responses, respectively. Given the allowable errors in c, and eqs. (90) and (91), it is thus easy to design G k (z) so that the requirements are satisfied.
To analyze the noise variance at the output of the system in FIG. 4 it is convenient to represent the synthesis filter bank with its so called polyphase realization according to FIG. 6 . The output sequence y(n) is obtained by interleaving the y i (m)'s, i=0, 1, . . . , M−1. The transfer function of the output y(n) is given by eq. (92), where Y(z) is given by eq. (93), X(z), Y(z), and G (p) (z) being defined in eqs. (94), (95), and (96), respectively. The G ik (z)'s are the polyphase components of G k (z) according to eq. (97).
As usual in noise analysis, the quantization errors are modeled as stationary white noise. Let x k (m), k=0, 1, . . . , N−1, be uncorrelated white noise sources having zero mean and variances σ xk 2 . Since G (p) (z) describes a linear and time-invariant system, the outputs y i (m), i=0, 1, . . . , M−1, are also stationary white noise with zero mean. However, the variances of y i (m), denoted here by σ yi 2 (n), are in general different, even when σ xk 2 are equal. The outputs y i (m) may also be correlated. The output noise y(n) will therefore generally not be stationary. Its variance, denoted here by σ y 2 (n), is thus time-variant. It is further periodic with period N since, obviously, eq. (98) holds.
We define the average quantization noise at the output in eq. (99). Given the synthesis filters G k (z) and its polyphase components G ik (z), (σ y 2 ) av can be computed as in eq. (100).
Now, let the synthesis filters be given by eq. (101) and all input variances σ xk 2 be equal according to eq. (102). Combining eqs. (100)-(102) gives us eq. (103).
A question that arises now is how to select the a k 's so that (σ y 2 ) av as given by (103) is minimized subject to the constraint that PR or RPR is simultaneously achieved. Let us consider the problem as defined by eq. (104). The constraint in eq. (104) is one of those that must be satisfied to obtain PR or RPR. Since the sum of the a k 's is M, the objective function to be minimized in eq. (104) can be rewritten as eq. (105). Hence, the solution to eq. (104) is obtained for a k =M/N, k=0, 1, . . . , N−1, with the minimum value of (σ y 2 ) av as in eq. (106).
This shows that the selection a k =M/N, for the time-interleaved ADCs and their generalizations minimizes the average quantization noise at the output.
In practice Δt k will no longer be exactly zero which implies that a k are replaced with a k +Δa k . If Δa k are small (and a k >0) the average quantization noise is in this case given by eq. (107). With a k =M/N, we obtain eq. (108). The quantity is obtained from eq. (83).
The present invention has considered the problem of reconstructing nonuniformly sampled bandlimited signals using digital filter banks. The overall system can be viewed as a generalization of the conventional time-interleaved ADCs, to which the former reduces as a special case. By generalizing the time-interleaved ADCs, it is possible to eliminate the errors that are introduced in practice due to time skew errors. We consider both perfect reconstruction (PR) and regionally perfect reconstruction (RPR) systems and it is shown how to obtain such systems by selecting the (ideal) digital filters properly.
The method for reconstructing a nonuniformly sampled bandlimited signal may be implemented in any suitable digital signal processing apparatus such as e.g. dedicated hardware, or a computer. The method is in the latter case performed by means of a computer program product comprising software code portions loaded into the internal memory of a suitable apparatus.
It will be obvious that the invention may be varied in a plurality of ways. Such variations are not to be regarded as a departure from the scope of the invention. All such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the appended claims.
The list of equations is presented at the following pages.
List of Equations
x ( n )= x a ( t )| t=nT , −∞≦n ≦∞ (1)
X ( j ω T ) = 1 T ∑ r = - ∞ ∞ X a ( j ω - j 2 π r T ) ( 2 ) T 1 = MT , f sample , 1 = f sample M ( 3 ) y ( n ) = { x ( n / M ) , n = 0 , ± M , ± 2 M , … 0 , otherwise ( 4 ) Y ( e jωT )= X ( e jωT 1 )= X ( e jMωT ) (5)
Y ( j ω T ) = ∑ k = 0 N - 1 G k ( j ω T ) X k ( j M ω T ) ( 6 ) X k ( j M ω T ) = X k ( j ω T 1 ) = 1 T 1 ∑ p = - ∞ ∞ H k ( j ω - j 2 π p T 1 ) X a ( j ω - j 2 π p T 1 ) = 1 MT ∑ p = - ∞ ∞ H k ( j ω - j 2 π p MT ) X a ( j ω - j 2 π p MT ) ( 7 ) Y ( j ω T ) = 1 T ∑ p = - ∞ ∞ V p ( j ω ) X a ( j ω - j 2 π p MT ) ( 8 ) V p ( j ω ) = 1 M ∑ k = 0 N - 1 G k ( j ω T ) H k ( j ω - j 2 π p MT ) ( 9 ) Y ( e jωT )= ce −jdωT X ( e jωT ), |ω T|≦π (10)
V p ( j ω ) = { c - j d ω T , p = rM , | ω | ≤ π / T 0 , p ≠ rM , | ω | ≤ π / T ( 11 ) x ( n )= x low ( n )+ x high ( n )
y ( n )= y low ( n )+ y high ( n ) (12)
X ( e jωT )= X low ( e jωT )+ X high ( e jωT )
Y ( e jωT )= Y low ( e jωT )+ Y high ( e jωT ) (13)
X low ( e jωT )=0, ω 0 T≦|ωT|≦π
X high ( e jωT )=0 , |ωT|≦ω 0 T
Y low ( e jωT )=0, ω 0 T≦|ωT|≦π
Y high ( e jωT )=0 , |ωT|≦ω 0 T (14)
Y ( e jωT )= ce −jdωT X ( e jωT ), |ω T|≦ω 0 T (15)
Y low ( e jωT )= ce −jdωT X low ( e jωT ), |ω T|≦π (16)
V p ( j ω ) = { c - j d ω T , p = rM , | ω | ≤ ω 0 0 , p ≠ rM , | ω | ≤ ω 0 ( 17 ) X a (jω)=0 , |ω|≧π/T (18)
K 0 =M −1 (19)
V p ( j ω ) = { c - j d ω T , p = 0 , | ω | < π 0 , | p | = 1 , 2 , … , K 0 , 0 ≤ ω ≤ π ( 20 ) X a (jω)=0, |ω|≧ω 1 (21)
x a ( t )= x a,low ( t )+ x a,high ( t ) (22)
X a (jω)= X a,low (jω)+ X a,high (jω) (23)
X low (jω)=0, |ω|>ω 0
X high (jω)=0, |ω|≦ω 0 , |ω|≧ω 1 (24)
0<ω 0 <ω 1 , ω 0 +ω 1 ≦2 π/T (25)
K 0 = ⌈ M ( π + ω 1 T ) 2 π ⌉ - 1 ( 26 ) K 0 = ⌈ M ( ω 0 T + ω 1 T ) 2 π ⌉ - 1 ( 27 ) V p ( j ω ) = { c - j d ω T , p = 0 , | ω | ≤ ω 0 A ( j ω ) , p = 0 , ω 0 ≤ | ω | ≤ π / T 0 , | p | = 1 , 2 , … , K 0 , | ω | ≤ ω 0 ( 28 ) x k ( m )= x ( nMT+t k ), k =0, 1 , . . . , N −1 (29)
H k ( s )= e st k , k =0, 1 , . . . , N −1 (30)
V p ( j ω ) = 1 M ∑ k = 0 N - 1 G k ( j ω T ) j ( ω - 2 π p MT ) t k ( 31 ) G k ( e jωT )= a k ce −jω(t k +dT) , |ωT|<π (32)
V p ( j ω ) = 1 M c - j d ω T ∑ k = 0 N - 1 a k - j 2 p MT t k ( 33 ) ∑ k = 0 N - 1 a k - j 2 p MT t k = { M , p = 0 0 , | p | = 1 , 2 , … , K 0 ( 34 ) G k ( j ω T ) = { a k c - jω ( t k + d T ) , | ω T | ≤ ω 0 T a k A k ( j ω T ) , ω 0 T < | ω T | ≤ π ( 35 ) V p ( j ω ) = { 1 M c - j d ω T ∑ k = 0 N - 1 a k - j 2 p MT t k , | ω T | ≤ ω 0 T A ( j ω ) , ω 0 T < | ω T | ≤ π ( 36 ) A ( j ω ) = 1 M ∑ k = 0 N - 1 a k A k ( j ω T ) j ( ω - 2 π p MT ) t k ( 37 ) Ba=c (38)
B = [ u 0 - K 0 u 1 - K 0 ⋯ u N - 1 - K 0 u 0 - ( K 0 - 1 ) u 1 - ( K 0 - 1 ) ⋯ u N - 1 - ( K 0 - 1 ) ⋮ ⋮ ⋮ u 0 K 0 u 1 K 0 ⋯ u N - 1 K 0 ] ( 39 ) u k = - j 2 MT t k ( 40 ) a=[a 0 a 1 . . . a N−1 ] T (41)
c=[c 0 c 1 . . . c 2K 0 ] T (42)
c k = { M , k = K 0 0 , k = 0 , 1 , … , 2 K 0 , k ≠ K 0 ( 43 ) a=B −1 c (44)
B=AC (45)
A = [ 1 1 ⋯ 1 u 0 u 1 ⋯ u N - 1 ⋮ ⋮ ⋮ u 0 2 K 0 u 1 2 K 0 ⋯ u N - 1 2 K 0 ] ( 46 ) C = diag [ u 0 - K 0 u 1 - K 0 ⋯ u N - 1 - K 0 ] ( 47 ) det A ≠0det B ≠0
det A =0det B =0 (48)
∑ k = 0 N - 1 a k = M , p = 0 ∑ N - 1 k = 0 a k [ u k p ] * = ∑ k = 0 N - 1 a k u k p = 0 , p = 1 , 2 , … , K 0 ( 49 ) ∑ k = 0 N - 1 a k * = M , p = 0 ∑ N - 1 k = 0 a k * u k p = ∑ k = 0 N - 1 a k * [ u k p ] * = 0 , p = 1 , 2 , … , K 0 ( 50 ) {circumflex over (B)}a=ĉ (51)
B ^ = [ B S ] ( 52 ) a=[a u a fix ] T (53)
ĉ=[c a fix ] T (54)
S=[S z S d ] (55)
S z = [ 0 0 ⋯ 0 0 0 ⋯ 0 ⋮ ⋮ ⋮ 0 0 ⋯ 0 ] , ( 56 ) S d =diag[1 1 . . . 1]. (57)
a={circumflex over (B)} −1 ĉ (58)
det B ^ = det B ~ ∏ l = 0 L - 1 S d , ll = det B ~ ( 59 ) B ~ = [ u 0 - K 0 u 1 - K 0 ⋯ u 2 K 0 - K 0 u 0 - ( K 0 - 1 ) u 1 - ( K 0 - 1 ) ⋯ u 2 K 0 - ( K 0 - 1 ) ⋮ ⋮ ⋮ u 0 K 0 u 1 K 0 ⋯ u 2 K 0 K 0 ] ( 60 ) t k =d k T+Δt k , k =0, 1 , . . . , M −1 (61)
d k =k, k =0, 1 , . . . , M −1
Δ t k =0 , k =0, 1 , . . . , M −1 (62)
G k (e jωT )= e −jkωT , |ωT|<π (63)
V p ( jω ) = 1 M ∑ k = 0 M - 1 - j 2 π p k M = { 1 , p = 0 0 , p ≠ 0 ( 64 ) ω 0 T ≤ 2 π ( K 0 + 1 ) M - ω 1 T ( 65 ) ω 0 T ≤ π ( M + 1 ) M - ω 1 T = π M + π - ω 1 T ( 66 ) t k =d k T+Δt k , k =0, 1 , . . . , N =1 (67)
d k = kM N , k = 0 , 1 , … , N - 1 ( 68 ) Δ t k =0 , k =0, 1 , . . . , N −1 (68)
G k ( jω T ) = M N - - j Mk ω T N , ω T < π ( 69 ) V p ( jω ) = 1 N ∑ k = 0 N - 1 - j 2 π p k N = { 1 , p = 0 0 , p ≠ 0 ( 70 ) ω 0 T ≤ π ( N + 1 ) M - ω 1 T ( 71 ) ∥ x∥ ∞ =max| x i |, 0 ≦i≦N −1 (72)
X ∞ = max ∑ k = 0 N - 1 x ik , 0 ≤ i ≤ N - 1 ( 73 ) ( B+ΔB )( a+Δa )= c. (74)
Δ B = [ Δ b - K 0 , 0 Δ b - K 0 , 1 ⋯ Δ b - K 0 , N - 1 Δ b - ( K 0 - 1 ) , 0 Δ b - ( K 0 - 1 ) , 1 ⋯ Δ b - ( K 0 - 1 ) , N - 1 ⋮ ⋮ ⋮ Δ b K 0 , 0 Δ b K 0 , 1 ⋯ Δ b K 0 , N - 1 ] ( 75 ) Δ b p k = j 2 π p k M ( jΔ t p k - 1 ) ( 76 ) Δ t p k = 2 π p MT Δ t k ( 77 ) ∥Δ B∥ ∞ ·∥B −1 ∥ ∞ <1 (78)
Δ a ∞ a ∞ ≤ Δ B ∞ · B - 1 ∞ 1 - Δ B ∞ · B - 1 ∞ ( 79 ) Δ B ∞ = max ∑ k = 0 N - 1 Δ b p k ≈ max ∑ k = 0 N - 1 Δ t p k ≤ N ( N - 1 ) π M · max { Δ t k T } . ( 80 ) ∥ B −1 ∥ ∞ ≦∥C −1 ∥ ∞ ·∥A −1 ∥ ∞ =1 (81)
Δ B ∞ · B - 1 ∞ ≲ N ( N - 1 ) π M · max { Δ t k T } . ( 82 ) Δ a ∞ ≲ a ∞ N ( N - 1 ) π M · max { Δ t k T } . ( 83 ) B′a=c′ (84)
B ′ = [ u 0 - K 0 u 1 - K 0 ⋯ u N - 1 - K 0 u 0 - ( K 0 - 1 ) u 1 - ( K 0 - 1 ) ⋯ u N - 1 - ( K 0 - 1 ) ⋮ ⋮ ⋮ u 0 N - K 0 - 1 u 1 N - K 0 - 1 ⋯ u N - 1 N - K 0 - 1 ] ( 85 ) c k = { M , k = K 0 0 , k = 0 , 1 , … , N - 1 , k ≠ K 0 ( 86 ) ( B+ΔB )( a+Δa )= c+Δc (87)
Δ c=BΔa+ΔBa+ΔBΔa (88)
∥Δ c∥ ∞ ∥B∥ ∞ ≦∥Δa∥ ∞ +∥ΔB∥ ∞ ∥a∥ ∞ +∥ΔB∥ ∞ ∥Δa∥ ∞ (89)
∥Δ c∥ ∞ <N max{|Δ a k |}+N max{|Δ t pk |}max{| a k |}+N max{|Δ t pk |}max{|Δ a k |}≈N (max{|Δ a k |}+max{|Δ t pk |}max{| a k |}) (90)
G k (e jωT )=[ a k +Δa k (ω T )] e −j[ωt k +Δt pk (ωT)] (91)
Y ( z ) = ∑ i = 0 M - 1 z - i Y i ( z M ) ( 92 ) Y ( z )= G (p) ( z ) X ( z ) (93)
X ( z )=[ X 0 ( z ) X 1 ( z ). . . X N−1 ( z )] T (94)
Y ( z )=[ Y 0 ( z ) Y 1 ( z ). . . Y N−1 ( z )] T (95)
G ( p ) ( z ) = [ G 00 ( z ) G 01 ( z ) ⋯ G 0 , N - 1 ( z ) G 10 ( z ) G 11 ( z ) ⋯ G 1 , N - 1 ( z ) ⋮ ⋮ ⋮ G M - 1 , 0 ( z ) G M - 1 , 1 ( z ) ⋯ G M - 1 , N - 1 ( z ) ] ( 96 ) G k ( z ) = ∑ i = 0 M - 1 z - i G ik ( z M ) ( 97 ) σ y 2 ( nM+i )=σ y i 2 (98)
( σ y 2 ) av = 1 M ∑ i = 0 M - 1 σ y i 2 ( 99 ) ( σ y 2 ) av = 1 M ∑ i = 0 M - 1 σ y i 2 = 1 M ∑ i = 0 M - 1 ∑ k = 0 N - 1 σ x k 2 ∑ n = - ∞ ∞ g ik ( n ) 2 = 1 M ∑ k = 0 N - 1 σ x k 2 ∑ i = 0 M - 1 ∑ n = - ∞ ∞ g ik ( n ) 2 = 1 M ∑ k = 0 N - 1 σ x k 2 ∑ n = - ∞ ∞ g k ( n ) 2 = 1 M ∑ k = 0 N - 1 σ x k 2 1 2 π ∫ - π π G k ( jω T ) 2 ω T ( 100 ) G k ( jω T ) = { a K - j Mk ω T / N , ω T < ω c T 0 , ω c T ≤ ω T ≤ π ( 101 ) σ x k 2 =σ x 2 . (102)
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) | The present invention refers to a method and apparatus for reconstruction of a nonuniformly sampled bandlimited analog signal x a (t), said nonuniformly sampled signal comprising N subsequences x k (m), k=0, 1, . . . , N−1, N≧2, obtained through sampling at a sampling rate of 1/(MT) according to x k (m)=x a (nMT+t k ), where M is an integer, and t k =kMT/N+Δt k , Δt k being different from zero. The invention comprises forming a new sequence y(n) from said N subsequences x k (m) such that y(n) at least contains the same information as x(n)=x a (nT), i.e. x a (t) sampled with a sampling rate of 1/T, in a frequency region lower than ω 0 , ω 0 being a predetermined limit frequency, by means of (i) upsampling each of said N subsequences x k (m), k=0, 1, . . . , N−1, by a factor M, M being a positive integer; (ii) filtering each of said upsampled N subsequences x k (m), k=0, 1, . . . , N−1, by a respective digital filter; and (iii) adding said N digitally filtered subsequences to form y(n). The respective digital filter is preferably a fractional delay filter and has preferably a frequency response G k =a k e (−jωsT) , k=0, 1, . . . , N−1, in the frequency band |ωT|≦ω 0 T, a k being a constant and s=d+t k , d being an integer. | 7 |
BRIEF DESCRIPTION OF THE PRIOR ART
Several types of hydraulically operated electrical output type braking systems are in use at the present time. One system is actuated by the electrical brake light indicator on the braking system of the towing vehicle. When the pedal is depressed the brake light is actuated which sends a signal to an integrating circuit. The integrating circuit applies a continually increasing voltage to the electrical solenoids in the brakes of the towed vehicle. In this device, the longer the brake pedal is depressed the more brake power is applied to the brakes of the towed vehicle. This type brake system tends to cause the brakes of the towed vehicle to eventually lock.
The second type of braking system uses a potentiometer-type circuit. Thus, as the brakes are depressed, the potentiometer is pushed from a minimum value to a maximum value. This type braking circuit tends to cause the power to be applied to the brakes in steps rather than a smooth transition from a point of no braking to a point of maximum braking. The system further does not provide for the need of pressing the brake electromagnet against the brake drum initially using a large current and then diminishing the current to match the amount of hydraulic pressure actually necessary to maintain the brake in a proper braking mode.
BRIEF DESCRIPTION OF THE INVENTION
This invention discloses an electrical circuit which has a transducer connected to the hydraulic braking circuit of the towing vehicle. As force is applied to the brake pedal of the towing vehicle, the hydraulic pressure is increased in the braking system of the towing vehicle. This increase in hydraulic pressure is transmitted to the transducer which causes an electrical output to develop from the transducer by an amount proportional to the pressure being applied in the hydraulic system. The electrical output from the transducer is applied to a comparator circuit which has an output which is subsequently amplified and applied to the electric brake of the towed vehicle. A feedback signal is taken from the signal eventually transmitted to the brake and applied to a second input of the comparator circuit. The comparator circuit then operates to maintain the feedback voltage as near the applied transducer voltage as possible. Since the applied transducer voltage is a measure of the hydraulic pressure actually being applied to the braking system of the towing vehicle, the feedback voltage would then be indicative of the voltage actually being applied to the brakes of the towed vehicle. Since the two will be matched, the towed vehicle will be braked by an amount substantially proportional to the braking amount of the towing vehicle. The circuit also includes an impulse generating circuit connected from the signal output of the circuit being applied to the brakes and to the transducer input of the comparator circuit. Thus when a signal is transmitted from the transducer to this input the impulse circuit will generate a large signal voltage which is applied initially to the electric brakes. The signal will then taper off permitting the feedback circuit to control the power being applied to the electric brakes thereby maintaining the towed vehicle brake power proportional to the pressure being applied to the hydraulic braking system of the towing vehicle. Other features and advantages of this invention can be observed by referring to the Figures and the following specifications.
OBJECTIVE OF THE INVENTION
An electrical brake control system for a towed vehicle having electrically operated brakes, wherein the control system is actuated by the hydraulic brake system of the towing vehicle in such manner as to cause braking of the towed vehicle proportional to the braking of the towing vehicle. The electrical brake control system includes a hydraulic pressure transducer having a hydraulic input connected to the hydraulic brake system of the towing vehicle and an electrical output proportional to the input hydraulic pressure. Means are provided in the remainder of the electric brake control system to cause the braking force of the electrically operated brakes in the towed vehicle to be substantially proportional to the electrical output of the hydraulic pressure transducer. Means are also provided in the electrical brake control system for adjustment of the proportionality constant to allow for differing towed vehicle load conditions and differing electric brake configurations.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a side view of a truck and a trailer showing the hydraulic circuit in the dotted lines in the truck and the electrical circuit in the dotted lines in the trailer;
FIG. 2 is a block schematic of the vehicle braking system, transducer, electrical brake control circuit, and the electrical brake unit in the towed vehicle;
FIG. 3 is an electrical schematic of the electrical brake control circuit.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a truck generally referred to by the number 10 has a hydraulic braking system 11 with hydraulic lines 12 traversing the length of the truck and to the rear of the truck for connection to a rear axle braking system 13. An extension of the hydraulic system through a hydraulic line 14 extends back to an electrical brake control circuit 15. From the output of the electrical brake control circuit 15 is coupled an electrical wire 16 which passes through the towed vehicle generally referred to by 17, through a wire 18 and to an electrical brake unit or brakes 19 in trailer 17. Brakes 19 are well known in the art and need not be further explained except to state that each of the brakes normally contains a pair of brake shoes which are spring-biased away from a brake drum. An electrical solenoid when powered, forces the brake shoe against the brake drum in the usual manner.
Referring to FIG. 2, a block diagram from the usual circuit is shown where the vehicle hydraulic braking system 11 as previous mentioned is coupled through a pipe 12 and pipe 14 to a hydraulic reservoir 20 which has a transducer 21 mounted therein and in fluid contact with hydraulic brake fluid 22 contained therein. Transducer 21 will be explained in more detail in references made to FIG. 3. From transducer 21 is an electrical connection 23 to electrical brake control circuit 15. Electrical brake control circuit 15 also contains a sensitivity control 24 and a brake unit selector 25. In the broad operation of this system illustrated in FIG. 2 when the hydraulic brakes are depressed by a pedal 9, vehicle hydraulic braking system 11 causes a pressure increase inside pipes 12 and 14 causing brake fluid 22 to increase in pressure in reservoir 20. The increase of pressure in hydraulic fluid 22 causees transducer 21 to generate an electrical output through wire 23 to electrical brake control circuit 15 which will then generate an output through wire 16 to a solenoid 27 causing brake shoes 7 to move against brake drums 26 braking the towed vehicle. Brake unit selector circuit 25 which will be later described, adapts the electrical brake control circuit 15 to various numbers of electrical brake units 19. For example, some trailers may contain two electrical brake units 19 for a pair of wheels, four for 2 pair of wheels, etc. An impulse generator 80 connects from wire 16 to wire 23 which is an input to electrical brake control circuit 15.
Referring to FIG. 3, a detailed electrical brake control circuit is illustrated. A transducer X1 is a wheatstone bridge type strain gauge of the monolythic silicon construction having approximately 1,800 ohms nominal resistance per arm. Bridge X1 comprises four arms 30, 31, 32 and 33. The junction between arms 30 and 33 is connected through a wire 34 to a filter capacitor 35. Wire 36 is connected through the remaining side of filter capacitor 35 to ground 37. The junction between arms 32 and 31 is likewise connected to a wire 38a to ground 37. Junction between arms 30 and 33 is connected through a wire 38b to a source of voltage 39. The junction between arms 33 and 32 is connected through a wire 40 to a fixed resistor 41 and variable resistor 42, and through a wire 43 to the junction between arms 30 and 31, which, in turn, is also connected to a first input terminal 44 of a comparator circuit generally referred to by arrow 45. The output of comparator circuit 45 is coupled through a wire 46 and a terminal 46a to an amplifier circuit means 47. The variable voltage, indicated as V1, at terminal 46a is the output from comparator circuit 45.
Amplifier circuit means 47 comprises a pair of amplifiers or transistors 48 and 49 connected in the usual manner to a source of voltage and a source of bias. A diode 50a connects the output emitter of transistor 49 to the base of final output amplifier transistor 50. The emitter of output amplifier transistor 50 is connected through a wire 51 to a brake unit selector circuit generally referred to by arrow 25 and comprises resistors 53, 54, and 55 which are connected respectively to wires 56, 57, 58 and to a selector switch 59 at terminals or taps 60, 61, and 62 respectively.
A selector arm 63 is connected through a wire 64, a resistor 65, and a resistor 112 to a potentiometer 69. The potentiometer 69 includes a resistor 66 and a variable arm 67 of which is coupled to the second input terminal 68 of comparator circuit 45. A diode 70 is connected between the collector of transistor 49 and the collector of transistor 50. The collectors of transistors 48 and 49 are coupled through a wire 72 to ground. Junction 73 is connecterd through a wire 16 to the remote electrical brake units in the towed vehicle generally referred to by the number 19. The brake contains the solenoid 27. Resistance 77 represents the D.C. resistance of the solenoid 27. Solenoid 27 is then coupled through a wire 78 to ground.
The impulse generator generally referred to by the number 80 has its input connected at junction 73 through a wire 81 to the second input 82 of a switching transistor circuit referred to by number 83. A first input 84 is coupled to a voltage dividing circuit comprising resistors 85 and 86 coupled between ground and a source of voltage 39. The output of switching transistor circuit 83 is coupled through a wire 87 to a differentiating circuit generally referred to by arrow 88 which comprises a capacitor 89 and a resistor 90 connected in parallel. Wire 91 is connected through a diode 92 to the first input terminal 44 of comparator circuit 45. The output of comparator circuit 45 through wire 46 is also coupled through a wire 100 to a zener diode 101 and through a wire 102 to a source of voltage 39. Resistors 110 and 111 furnish bias for the transistors 48 and 49 respectively.
OPERATION
The hydraulic pressure on transducer X1 controls a linerally proportional current Ib through the external brake circuit comprising wire 16, solenoid 27 through wire 78 to ground. It does so in the following manner: The voltage output of transducer X1 is applied to the positive or first input node of comparator circuit 45. The bias network for comparator circuit 45 consists of resistors 66, 65, and 112 and a selected portion of a resistor network which comprises resistors 53, 54, and 55 which are selectively inserted into the circuit by means of selector switch 59 and terminals 60, 61, or 62 respectively.
The selector switch 59 comprises a means for adjusting the total feed back voltage generated by current Ib as it flows through the battery 39, wire 51 through transistor 50 to junction 73 through wire 16 and brake units 19 through wire 78 to ground. The voltage thus generated across one or more of the resistors 55 through 53 is applied to resistors 65, 66, and 112 to the negative input terminal 68 of comparator circuit 45. Adjustable potentiometer 69 is varied by moving variable arm 67 until the proper bias voltage is applied to the negative input terminal 68. For proper setting, no brake pressure is applied, and bridge X1 presents a steady voltage of about 6 volts to positive input terminal 44 of comparator circuit 45. Potentiometer variable arm 67 is then adjusted until the voltage at negative input terminal 68 is slightly less or closer to ground than input terminal 44. This setting forces the output voltage at terminal 46a to approach the positive supply voltage 39 and therefore shuts off the amplifier circuit means 47 consisting of transistors 48, 49, and 50. Diode 50a is an additional P.N. junction diode, and inserted in the amplifier to insure that comparator circuit 45 can completely shut off transistor 50 under the maximum tolerance condition of comparator circuit 45.
As pressure on X1 increases the voltage output of X1 decreases in potential. When the voltage output of X1 becomes closer to ground potential than the voltage at the input of the negative input terminal 68 of comparator circuit 45, V1 lowers toward ground potential thus turning on the amplifier transistors 48, 49, and 50. As amplifier transistor 50 is turned on the current IR through resistor string 53, 54, and 55 (IR is proportional to Ib) causes a voltage drop to develop across these aforementioned resistors. This voltge drop causes the bias voltage at the minus terminal 68 of comparator circuit 45 to decrease by an amount approximately one-half that of the voltage drop developed across resistors 53 and 55. Because of the extremely high gain of the transistor amplifiers comprising transistors 48, 49, and 50, V1 will continue to lower toward ground potential, Ib will continue to increase and the voltage drop across the resistor series will continue to increase until the bias voltage at the negative input terminal 68 to comparator circuit 45 is again as close or closer to ground potential than the voltage at the positive input terminal 44 of comparator circuit 45. The feedback relationship is stable because d(e-)/dt (e- is the voltage at X1 output terminal 23) and d(er)/dt (er is the voltage drop across resistor string 53 through 55) are always the same sign and appear on input nodes of comparator circuit 45 whose effects on the output voltage V1 are 180° out of phase, and also because comparator circuit 45 is internally phase compensated over a wider frequency range than the response of transistor 50.
The electro-mechanical properties of the electric brake units 19 prevent actuation of braking effect until an indeterminate and variable threshold voltage between approximately 2-1/2 and 3-1/2 volt is reached. When this threshold is exceeded, sudden actuation of one or more electric brake units occurs. If the brake electromagnet voltage is allowed to remain applied to the brakes, brake grab or lock up can (and usually does) occur under conditions of light trailer loading. It has been determined experimentally, however, that once brake actuation is achieved, braking action is essentially proportional to brake voltage over a brake voltage range of from 0.5 volts to 12 volts.
Circuitry consisting primarily of switching transistor circuit 83, capacitor 89, and resistors 85 and 86 prevent grab and allow proportional braking control by adding an impulse voltage to the input terminal 44 of comparator circuit 45 in the following manner: With no pressure on X1 brake voltage VB at junction 73 is zero (ground potential) and the voltage at negative input terminal 82 of switching transistor circuit 83 is zero. The voltage on the positive input terminal 84 of the switching transistor circuit 83 is a positive voltage of approximately 0.8 of a volt which is determined by the bias network comprising resistors 85 and 86. Under the above conditions, the voltage at wire 87 is forced to approach the positive supply voltage 39 which back-biases diode 92 and allows capacitor 89 to discharge through resistor 90. When brake voltage VB exceeds the bias voltage on the positive input terminal 84 of amplifier or switching transistor circuit 83 the high gain of amplifier 83 forces the voltage at wire 87 to approach ground potential. Capacitor 89 at this instant begins to charge through diode 92 which presents a low impedance path from the positive input terminal 44 of comparator circuit 45 to virtual ground. This condition forces V1 towards ground potential, limited only by the zener voltage of diode 101. Diode 101 prevents Veb (max) of transistor 48 from being exceeded and the base-emitter junction from being destroyed. The feedback voltage from selector switch 59 is insufficient to bring the positive and negative input terminals 44 and 68 respectively to equal potential so the transistors 48, 49, and 50 saturate putting miximum brake voltage on electrical brake unit 19. The amplifier string consisting of transistors 48, 49, and 50 will remain saturated until capacitor 89 has charged sufficiently to allow the voltage at the anode of diode 92 to come within the control range of the feedback system at terminal or input 68 of comparator circuit 45. From that time the brake voltage will decrease exponentially to a value just in excess of the switching transistor circuit 83 switching threshold value set by resistors 86 and 85. The hysteresis effect is caused by the small additional current sunk to ground from the positive input terminal 44 of the comparator circuit 45 through diode 92, resistor 90 and the output of amplifier 83. The circuit is also inherently stable in spite of the 90° phase shift introduced by the differentiation in capacitor 89 because diode 92 in effect removes amplifier 83 and capacitor 89 from the comparator circuit 45 feedback loop when diode 92 is back biased.
BRAKE UNIT SELECTOR CIRCUIT
Brake unit selector circuit 25 which is previously mentioned consists of resistors 54, 53, and 55 along with selector switch 59. These resistances are adjusted so that the feedback voltage being applied to terminal 68 through the feedback network including resistors 65, 66, and 112 will be appropriate to control the number of electric brake units actually being connected in parallel with wire 16. If a two-solenoid or dual electric brake unit is used, for example, selector switch 59 will be connected to terminal 60. If a four-solenoid unit is required, selector switch 59 will be connected to terminal 61; and if a six-solenoid unit, for example, is needed selector switch 59 will be connected to terminal 62 so that the voltage being fed back will be proportional to the current being demanded for each of the units connected in parallel with electric brake unit 19. Selector switch 59 must be a shorting type to prevent introduction of undesired transients during switching due to momentary loss of bias voltage to the negative input terminal 68 of comparator circuit 45. Resistor 41 and adjustable resistor 42 provides a shunting effect to the output voltage of transducer X1 thereby permitting the transducer to be adaptable to various braking systems and various conditions under which vehicles are being towed. Filter capacitor 35 provides filtering for the input voltage thereby removing as much electrical noise from the transducer supply voltage as possible. The above is necessary because of the narrow output voltage range of the transducer X1.
In an embodiment of this invention which was actually constructed operational comparator circuit 45 and switching transistor circuit 83 are a dual I.C. operational amplifier type 5558. Diode 92 is a 1N914 silicon diode, diodes 50a and 70 are 1N4001 silicon rectifiers, filter capacitor 35 is a 100 microfarad. Capacitor 89 is a 2 microfarad. Transistor 48 is a 2N2907. The transistor 49 is a T.I.P. 32 P.N.P. silicon transistor, and transistor 50 is a 2N6329 P.N.P. silicon transistor (both transistors 49 and 50 are manufactured by Texas Instruments, Inc.). Resistor 41 is 680 ohms; resistor 42 is 10 K ohms; resistors 65 and 112 are 1.70 ohms; resistor 66 is 100 ohms 10-turn-trimmer. Resistor 90 is a 2.4 meg ohm; resistor 110 is a 1.0 ohm; and resistor 111 is a 100 ohm; resistor 53 is a 4.7 milli ohm; resistor 54 is a 1.39 milli ohm; resistor 55 is a 2.78 milli ohm; resistor 86 is a 6.8 K ohm and resistor 85 is 430 ohms. Diode 101 is a 4.7 volt zener diode.
CONCLUSIONS
A circuit has been illustrated which provides proportional electrical brake control of the towed vehicle which relates to the pressure being applied to the hydraulic braking system of the towing vehicle. The circuit also provides for a momentary application of instantaneous voltage to the braking system of the towed vehicle so that the brake magnets will rapidly move against the brake drums. The instantaneous voltage is soon removed permitting the system to return to the proportional control mode. This system also provides means for adapting the circuit to various numbers of electric braking units employed, and for adjustment depending on the load and type of the vehicle being towed.
While the preferred embodiment has been declared using a hydraulic braking system, it is obvious that any fluid would actuate the transducer, whether it is compressible or incompressible. For example, air as used in air brakes would operate the tranducer in a manner similar to the hydraulic fluid. This invention is intended to cover either type fluid. While the transducer was illustrated as being connected by an extension 14, it is obvious that it can be mounted at any location in the pressure circuit including directly on the master cylinder.
It is obvious that various changes and modifications can be made in the invention described in the specifications and claims, and still be within the spirit and scope of this invention. | An electrical brake control system for a towed vehicle having an electric brake, where the control system is actuated by the hydraulic brake system in the towing vehicle. The electrical brake control system includes a hydraulic pressure transducer having a hydraulic input connected to the hydraulic brake system of the towing vehicle and an electrical output proportional to the hydraulic pressure developed by the hydraulic system. A comparator circuit has first and second inputs and an output. A circuit connects the first input to the electrical output of the hydraulic pressure transducer and a second circuit connects the output from the comparator circuit to the electrically operated brake in the towed vehicle. A feedback system connects the electrically operated brake to the second input of the comparator circuit such that the comparator circuit always maintains the feedback voltage to the second input substantially identical with the voltage of the first input. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a delivery and conditioning system in a furnace for carrying molten thermoplastic material therethrough from the furnace and discharging same at some desired temperature and consistency. The invention more particularly pertains to a glass delivery system wherein the glass is conditioned to a desired relatively uniform temperature and viscosity by means of a heat exchange device for efficiently and economically removing heat from the material in order to achieve the desired result.
Vertically oriented electric glass melting furnaces have been known in the prior art for some time, but it has been only in the last several years that such furnaces have been brought to large scale commercial application. In more recently developed furnaces, such as the type illustrated in U.S. Pat. Nos. 2,993,079, 3,524,206, 3,582,861, 3,725,558, 3,742,111, 3,942,968, 4,029,887 and 4,143,232, glass forming batch materials are fed to the upper end of a vertical chamber and refined molten glass is withdrawn from the bottom of the chamber. High quality glass is thus produced in a single vertical chamber, with melting occurring in an upper portion thereof and preferably some refining occurring at the bottom portion.
The molten glass withdrawn from the electric furnace is usually received within a laterally extending connected channel situated at one side of the furnace bottom and thereafter is usually directed through a vertical passageway or riser to a mixing chamber and/or a forehearth. For example in U.S. Pat. No. 3,942,968 to Pieper, the molten glass is withdrawn laterally from the furnace through a connected channel, thereafter is directed to a riser portion where colored materials may be added, from the riser to a downwardly extending mixing chamber, laterally from the chamber through a second connected channel, then upwardly through a second riser, and finally to a forehearth or feeder. In the Pieper system, the delivery passageway extending from the furnace bottom is formed in refractory block material of the contiguous walls of the furnace and riser, and an electrode is positioned in the passageway. It will be appreciated by those skilled in the art of melting glass that the passageway electrode may not be used when coalesced forming or batch material surrounds the electrode because the cold material will not be electrically conductive.
In some electric glass melting furnaces heretofore employed, a refractory metal delivery conduit extends from near the center of the bottom of the furnace to the confines or passageway of the connected channel. The conduit is either placed on the furnace bottom wall or is laid into a trough incorporated in the furnace bottom wall; and the conduit is protected from exposure to solid or liquid contaminants, which originate in the batch and sink through the molten glass, by a cover or refractory block. The delivery system of such type of prior art furnace is provided with devices for heating the cold glass or raw material initially within the conduit; because, during the startup or beginning stage of operation of the furnace, the heat conducted through the conduit from the molten glass in the furnace and connected channel to the glass or raw materials is not sufficient to melt all the cold batch material initially within the conduit.
In the U.S. Pat. No. 4,029,887 to Spremulli, such an apparatus is disclosed for heating glass or raw materials within a delivery conduit extending from an electric glass melting furnace to a connected channel. The conduit is made of an electrically conductive refractory material such as molybdenum (moly) and is used to conduct current from inside the furnace to its exit end in the channel. Joule effect heating between the exit end of the conduit and the electrode in the connected channel indirectly causes the cold glass or raw materials within the conduit to partially melt, to the extent that the materials within the conduit would begin to flow therefrom. A flange assembly for use with the molybdenum conduit is also disclosed. The delivery conduit connects the furnace with a forehearth channel wherein the glass is conditioned.
It is well known in the art that forehearths require substantial amounts of heat energy in order to condition the glass from the furnace temperature at the inlet to some desired forming temperature at the outlet thereof. Thus the forehearth is a net consumer of energy and the anomalous condition exists wherein heat energy input is required to "cool" the glass to the proper forming temperatures.
It is well known that molybdenum, a preferred glass contact material used herein, has significantly higher wear resistance to moving molten glass than conventional refractory materials. However, it is also well known that moly tends to oxidize at temperatures in excess of 550°-600° C. and thus the moly must be protected from deleterious atmosphere (oxygen) when it is used at or above these elevated temperatures. In Spremulli, '887, although the outlet pipe is preferably manufactured of moly and various devices are provided for protecting the moly from oxidation, energy input to the forehearth is required for conditioning the glass.
In the British Pat. No. 1,412,599 commonly assigned to the assignee herein, a delivery system utilizing stationary mixing devices and a heat exchange vessel, is disclosed. The system does not consider the problem of high heat loss since it is located downstream of the forehearth in a forming operation.
The present invention performs the functions of transportation, cooling, and homogenizing molten glass, wherein the useful life of the delivery system is significantly increased and further the system is a net producer of energy in a portion of a furnace wherein heretofore energy has been utilized to remove energy from the glass.
SUMMARY OF THE INVENTION
There has therefore been provided a delivery system for conducting molten thermoplastic material from a furnace comprising, a pipe member having an inlet adapted to receive the material at one end from the furnace and an outlet for delivering the material at a desired homogeneity at a remote outlet location thereof. An insulated shell structure is located concentrically about the pipe and defines an insulated closed space thereabout for retaining heat therewithin. The shell structure has inlets and outlets for circulation of a heat exchange fluid in at least a portion of the space between the pipe and the shell. The heat exchange fluid removes heat from the thermoplastic material flowing through the pipe member to condition same to the desired homogeneity. Means is included for shielding the inside surfaces of the space between the shell and the pipe from deleterious ambient including a purge fluid which may act also as the heat exchange fluid.
The present invention may thus be provided with a purge gas acting as a heat exchange fluid to directly cool the thermoplastic material flowing through the inner pipe or alternatively may be provided with a purge fluid for protecting the pipe and shell and another fluid for cooling the glass. Each of the aforementioned alternatives are within the scope of the present invention and it is contemplated that the use of one or the other of such alternatives is within the option of operating, for example, a glass melting furnace.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional elevation of the delivery system of the present invention with a portion of a furnace shown to illustrate the environment.
FIG. 2 is a schematic cross section of an alternative embodiment of the present invention.
FIG. 3 is a schematic of a circulating system for a heat exchange and a purge fluid.
Pipe wall thicknesses are not shown in the above drawings since the illustrations are schematic in nature. In general heavy lines are used to emphasize a pipe or structure wall thickness.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is illustrated a portion of a vertically oriented electric furnace 10 for melting thermo-plastic material 9, such as glass, having a bottom wall 11 and an outlet or delivery conduit 12 vertically extending through an opening 14 therein. Delivery conduit 12 may extend from above the bottom wall 11 to a position extending below same for mating with delivery system 16 of the present invention. The delivery conduit 12 has a lower end portion or outlet 18 and the delivery system 16 has an upper inlet end 20 closely spaced and in axial alignment therewith. A flange 22 coupled to the delivery conduit 12 at inner radial end 24 supports the delivery conduit 12 in the manner hereinafter described. A flange 26 supports the delivery system 16 at an inboard end 28 also in a manner hereinafter described.
Since it is possible for the glass or thermo-plastic material 9 in the furnace 10 to seep between the opening 14 in furnace bottom wall 11 and the delivery conduit 12, means is provided for freezing the molten thermoplastic material 9 in a space 30 between a refractory block 32 and flange 22. The means includes a cooling pipe 36 welded to a metal support block 38 which in turn is supported by bolts 40 attached to support plate 41 for the bottom wall 11 of the furnace 10. The pipe 36 carries cooling fluid such as water and freezes the glass 9 in a zone 31 contiguous therewith and prevents leakage from the furnace. The flange 22 is supported at an outboard end 42 by the support plate 38 and thus the delivery conduit 12 is held vertically within the furnace bottom 10. Similarly the flange 26 rests at an outboard end 44 on a support plate 48 which is also held by the bolts 40. Fluid pipe 46 is mounted between the support plate 38 and flange 48 to freeze glass 9 seepage from outlet 18 into space 33 between the flanges 22 and 26.
The delivery system 16 of the present invention may generally be described with respect to FIG. 1 as follows. A first pipe 50 preferably fabricated from molybdenum is closely spaced with or may mate at its inlet end 20 with the outlet 18 of delivery conduit 12. The pipe 50 receives the molten thermo-plastic material 9 at the upper end and delivers said material from a lower outlet end 52 thereof. Within the pipe 50 there may be provided mixing means (not shown) for homogenizing the glass 9 as it passes therethrough. For example, one or more stationary mixer elements of the type described in U.S. Pat. Nos. 2,861,596 and 3,635,444 could be conveniently used. In addition to flange 26 at inlet 20, support for the pipe 50 and the delivery system 16 may be provided by a flange member 56 which is welded or otherwise secured to the pipe 50 at inboard end 58 and supported at an outboard radial end 60 by some fixed support 62.
Located about the first pipe 50 is a concentric pipe 64 which may also be fabricated from molybdenum. The pipes 50 and 64 define an annular space 66 therebetween wherein heat exchange or purging fluid may be provided. Inlet and outlet pipes 68 and 70, each having inboard openings 75 in communication with space 66, are secured in respective openings 72 and 74 of the outer pipe 64 and provide for the circulation of fluid F through the space 66. The source of fluid F is not illustrated. The fluid F may be an inert gas with respect to the heated molybdenum pipes 50 and 64 and further may be either a recirculated or single pass fluid. It is recognized that it would not be economical as a general practice to circulate an inert gas in a single pass mode, thus, it is contemplated in the present invention, that if the fluid F is inert and is used as described herein, it would be recirculated. Means would be provided to make up for any leaks in the system.
An insulative structure 78 surrounds the outer pipe 64 and defines yet another space 76 therebetween. Structure 78 may be manufactured and constructed of different layers and grades of insulative refractory materials in order to retain the heat within the delivery system 16. Openings 73 are provided in pipes 68 and 70 so that fluid F may be circulated in the space 76 between outer pipe 64 and structure 78, since the outer surface of pipe 64 must also be protected from oxygen. The system is then rendered more efficient by allowing the fluid F to carry away controlled amounts of heat as determined by its circulation rate.
A shell 80 surrounds the structure 78 and encloses the system. It is mounted between lower support 62 and an upper flange support 48. Openings 82 are provided in shell 80 for the respective inlet and outlet pipes 68 and 70. The entire delivery system 16 is welded or suitably air sealed so that local ambience cannot enter the system to any deleterious extent. Any leaks occurring in the system would be compensated for by overpressure in the circulation of the fluid F.
Heater elements 84, preferably in the form of glow bars are provided in the space 76 between the outer pipe 64 and the structure 78. During startup heater elements 84 may be electrically energized and brought to an elevated temperature to heat pipe 50 and unmelted batch therein. It should be realized that the heater elements 84 might also be utilized to add heat to the delivery system 16 in the event that a certain temperature gradient would be desirable. For the most part however, the heater elements 84 are supplied and incorporated into the delivery system 16 for purposes of startup.
The mixing means (not shown) but referred in the '596 and '444 patents above may be located within pipe 50 to shear, split and homogenize the glass 9. Thus, temperature and physical inhomogeneities (e.g. cords) are progressively removed from the glass 9 moving therethrough.
Sometimes hereinafter, the system described with respect to FIG. 1 may be called a direct heat exchange system. That is, there is a direct heat exchange relation between the thermoplastic material 9 moving through the pipe 50 and the fluid F moving through the spaces 66 and 76. Preferably, the fluid F in the direct heat exchange system is an inert gas and acts not only a heat exchange fluid but a purge gas, thus preventing the infiltration of deleterious oxidizing elements in the atmosphere. The direct system has the advantage that, only one fluid F is required and there is the possibility of enhancing the control of the system by regulating the flow of the fluid F therethrough. The heat carried by the fluid F from the outlet pipe 70 may be coupled to an indirect heat exchange unit 90 as illustrated in FIG. 3. The outlet pipe 70 becomes the inlet for the heat exchanger 90. Pump 92 pressurizes and circulates the fluid F to the inlet 68 of the delivery system 16, and a valve 94 coupled to a source of inert gas (not shown) provides make up gas for the system. A second heat exchange fluid F2 may be provided to cool the heat exchanger 90 and use the heat provided thereby for other useful purposes in the manufacture of glass or as desired by the system user. For example, it has been thought that heated gas may be used to preheat batch materials to thereby increase the efficiency of the glass making process.
In FIG. 2 there is illustrated another embodiment of the present invention, sometimes hereinafter referred to as an indirect heat exchange system. A delivery system 116 has an inner pipe 150 which receives molten thermo-plastic material 9 at an inlet end 120 thereof and delivers conditioned material to an outlet end 152 thereof. Stationary mixer elements (not shown), similar to those described with respect to FIG. 1, may be located inside the pipe 150 and are briefly noted herein.
A second or outer pipe 164 surrounds the inner pipe 150 and defines a space 166 for the circulation of purge fluid P therebetween. Heater elements 84, similar to those described with respect to FIG. 1 are included in the space 166 between the pipes 150 and 164. A concentric shell member 100 is disposed about the outer pipe 164 to define a space 102 through which a heat exchange fluid Ex such as water may be circulated. An outer shell 180 similar to the shell 80 in FIG. 1 is provided to surround or encapsulate the entire system 116. Insulative structure 178 between shell member 100 and outer shell 180 prevents heat loss from the system. An inlet pipe 168 for purge fluid P communicates with the space 166 between the respective inner and outer pipes 150 and 164 and an outlet pipe 170 communicates at an opposite end thereof to provide an outlet for the purge fluid P. Inlet 104 for heat exchange fluid Ex communicates with the space 102 between outer pipe 164 and shell member 100. Likewise outlet pipe 106 communicating with space 102 carries heat exchange fluid Ex away.
The purge fluid P protects the heater elements 84 and opposed surfaces of the metal forming the respective inner and outer pipes 150 and 164 within space 166. The heat exchange fluid Ex cools the system indirectly by heat exchange via an intermediate space (e.g. space 166). The fluid P used for purging may be circulated as in FIG. 3 by pump 92 and upstream makeup valve 94. A heat exchanger 90 similar to the arrangement shown in FIG. 4 may be provided to reclaim heat from heat exchanger fluid Ex. The heat obtained by passing fluid F in heat exchange with the system 116 could be blown off as waste heat in a single pass manner or conserved. If practical the latter would be preferable. The indirect system illustrated in FIG. 2 would thus preferably be provided with at least one heat exchanger for cooling the heat exchange fluid Ex and possibly one for claiming available energy from the purge fluid P. Variations of this system may be provided by incorporating the cooling of the purge fluid P and the heat exchange fluid Ex in a combined heat exchanger.
In the system of FIG. 2, smaller quantities of purge fluid P are required because it protects the oxidizable pipe members 150 and 164 while the surrounding heat exchange fluid Ex provides the substantial cooling for conditioning the molten thermoplastic material 9 passing through the pipe 150. In the direct system of FIG. 1 a larger quantity of fluid F is required, since it must both protect the oxidizable components and remove heat. One advantage of the system described in FIG. 2 is that the quantity of heat exchange fluid Ex may be substantially reduced by the use of water. Whichever system is chosen, by virtue of the economic and engineering constraints, each is contemplated to be within the scope of the present invention and either one may become the preferred embodiment of the present invention.
In both of the embodiments of FIG. 1 and FIG. 2 insulative structures 78 and 178 prevent heat loss other than as provided by the controlled passage of cooling fluids through the system. Thus the present invention provides for the retention of heat within the confines of the delivery system and the removal thereof only under conditions as provided for in the controlled cooling of thermoplastic material passing therethrough. The heat retention provided by insulative structures 78 and 178 help to homogenize the material 9 to a more uniform temperature and viscosity.
Temperature control in the present invention is versatile since the flow rate of cooling fluid may be varied to a greater or lesser degree depending on the rate of heat transfer desired. Further the type of cooling fluid may be changed from one liquid to another and will have a significant effect on the heat transfer parameters (e.g. liquid or gas). Heat may be added by heaters adjacent the inner pipe although this is not generally preferred.
The present system is relatively small in dimension but can handle large heat transfer rates. For example in FIG. 2 the inner pipe 50 would be about 2" I.D. With such a small diameter pipe, heat transfer would be rapid and thermal inertia relatively small in comparison to conventional devices. Mixing means referred to above would further enhance heat transfer.
Temperature control of the various cooling and purge fluids and the glass can be controlled to a better precision by appropriate feedback of temperature information especially if the system reacts relatively quickly due to reduced thermal inertia.
The present invention may thus provide for a very high heat transfer rate without the addition of additional energy to cool glass. If desired, it can be a net producer of energy, and thus, the invention would provide a more economical use of energy resources available. The system, by utilizing a molybdenum delivery pipe as described herein, would have an extremely long life as experience has taught in the use of such materials in other delivery systems. Functionally the system may be operated so that it provides for uniform composition and temperature homogeneity of the material in a relatively small unit and with improved control.
In a series of related U.S. patent applications Ser. Nos. 243,811; 244,001; 244,002 filed this same date and assigned to the assignee herein, various arrangements of glass melting and transport systems are disclosed in detail. It should be understood that to the extent necessary, the teachings of said applications should be considered incorporated herein by reference.
While there have been described what at present are considered to be the preferred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is intended in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention. | There has been provided a delivery system for conditioning molten thermo-plastic material, wherein a first pipe member, having an inlet at one end adapted to receive the material and an outlet at an opposite end for delivering the material therefrom at a desired homogeneity is coupled at its inlet end to a furnace. An insulated shell structure, having at least one fluid inlet and outlet therein, is located concentrically about the first pipe member and defines a closed insulated space thereabout. The shell is adapted to receive heat exchange fluid for circulation from the inlet to the outlet in said closed space for removing heat from the thermo-plastic material flowing through the pipe member. Means is provided for shielding inside surfaces of space between the shell and the pipe member from deleterious ambient including a purge fluid which may act alone as the heat exchange fluid. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. Provisional Patent Application No. 62/315,563, filed on Mar. 30, 2016, the disclosure of which is incorporated herein by reference in its entirety.
STATEMENT OF INTEREST
[0002] The invention described herein was made in the performance of work under a NASA contract NNN12AA01C, and is subject to the provisions of Public Law 96-517 (35 USC 202) in which the Contractor has elected to retain title.
TECHNICAL HELD
[0003] The present disclosure relates to spacecraft thrusters. More particularly, it relates to a Hall effect thruster electrical configuration.
BRIEF DESCRIPTION OF DRAWINGS
[0004] The accompanying drawings, which are incorporated into and constitute a part of this specification, illustrate one or more embodiments of the present disclosure and, together with the description of example embodiments, serve to explain the principles and implementations of the disclosure.
[0005] FIGS. 1 and 2 illustrate an exemplary I-fall thruster system on a spacecraft.
[0006] FIG. 3 illustrates exemplary cathode placements.
[0007] FIG. 4 illustrates an exemplary cathode assembly.
[0008] FIG. 5 illustrates an exemplary Hall thruster system on a spacecraft.
[0009] FIG. 6 illustrates a cathode common circuit for a Hall thruster system with insulating pole piece surfaces.
[0010] FIG. 7 illustrates a Hall thruster system conducting pole pieces where the current loop through the thruster body closes in the plume plasma.
[0011] FIG. 8 illustrates current loops for a Hall thruster system with conducting pole pieces and the thruster body at cathode common.
[0012] FIG. 9 illustrates testing electrical configurations.
[0013] FIG. 10 illustrates covered and non-covered pole pieces.
[0014] FIG. 11 illustrates an exemplary voltage-current characteristic of a Hall thruster body.
SUMMARY
[0015] In a first aspect of the disclosure, a Hall thruster is described, comprising: a thruster body comprising an annular discharge chamber having an inner wall, the entire inner wall being made of a first electrically conductive material and having a rear surface with an aperture in the inner wall defined therein; said inner wall of said annular discharge chamber having a downstream end, a radially inner surface, and a radially outer surface, wherein said radially inner surface and said radially outer surface respectively radially inwardly and radially outwardly bound said annular discharge chamber; an anode/gas distributor having an anode electrical terminal, said anode/gas distributor situated in said aperture defined in said rear surface of said annular discharge chamber, said anode/gas distributor having at least one inlet configured to receive an ionizable gas and configured to distribute said ionizable gas for use as a propellant; a cathode neutralizer configured to provide electrons, said cathode neutralizer having a cathode electrical terminal that can be connected to said anode electrical terminal by way of a first power supply and a switch, said cathode neutralizer and said anode/gas distributor when operating generating an axial electrical field within said annular discharge chamber; and a magnetic circuit having a magnetic yoke, an inner magnetic coil and an outer magnetic coil, said magnetic circuit configured to be switchably powered, said magnetic circuit configured to provide a substantially radial magnetic field across an annular aperture of said annular discharge chamber, said magnetic circuit configured to provide magnetic shielding of said inner wall of said annular discharge chamber from high-energy ions, wherein the cathode electrical terminal is electrically connected to the thruster body by way of a second electrically conductive material, thereby electrically biasing the thruster body to an electrical potential level of the cathode electrical terminal.
DETAILED DESCRIPTION
[0016] Hall effect thrusters are a type of electric propulsion used in multiple commercial, military, and civil applications. The development of these devices requires careful attention to the manner in which they are tested on the ground and the particular details that enable their operation for the many thousands of hours of operation which are necessary for typical space missions.
[0017] One particular ground test effect is the conduction of current through the thruster chassis or body. Current conducted through the chassis may not be present in a space environment, and the absence of that current has the potential to de-stabilize the discharge, induce high thermal loads, and reduce thruster lifetime. Chassis current is typically limited in existing Hall thrusters that are flown in space through the use of insulating coatings on the pole piece faces that are exposed to the relatively dense, relatively high temperature plasma in front of the thruster.
[0018] The lifetime of Hall thrusters has typically been limited by erosion of their discharge chamber walls, but this can be greatly extended through the use of magnetic shielding (see for example U.S. Pat. No. 9,453,502, “Metallic Wall Hall Thrusters”, the disclosure of which is incorporated herein by reference in its entirety). Experiments conducted at the Jet Propulsion Laboratory have shown how magnetic shielding, while increasing discharge chamber lifetimes by orders of magnitude, can also create conditions near the pole piece faces that cause significant erosion. These erosion rates are high enough that most insulating coatings can no longer be used because they do not provide a high enough sputter resistance to ion bombardment. The erosion process leads to the use of conducting coatings with low sputter yields, such as graphite.
[0019] Most existing Hall thrusters using insulating coatings are not magnetically shielded by virtue of their magnetic field topology, and are referred to as unshielded Hall thrusters. These thrusters have lifetimes of just a few thousand hours, limited by the erosion of their discharge chamber walls, which eventually exposes the pole pieces and leads to their sputtering and subsequent failure. Methods to protect the pole pieces of unshielded Hall thrusters are also highly desirable, as this could greatly extend the lifetime of many existing Hall thrusters currently flown in space in commercial, military, and civil applications.
[0020] Hall thrusters typically operate at 300-400 V in space. Achieving a so-called high-voltage Hall thruster that operates at greater than 400 V is significantly complicated by increased electron transport, which reduces efficiency, as well as the increase in ion energy, which increases sputtering and reduces lifetime. It would be highly desirable to achieve thruster configurations that enable high-voltage operation and long lifetime. There are no known solutions for achieving high-voltage, long-lifetime operation in a Hall thruster and that are also qualified for space flight.
[0021] As described in the present disclosure, the ground test and lifetime issues can be eliminated through an electrical configuration of the Hall thruster that addresses both. Multiple implementations are possible and some examples in particular are described herein.
[0022] In a first implementation, the thruster chassis (body) is electrically biased to the potential of the cathode (i.e, cathode common). This configuration requires that the thruster chassis is electrically isolated from the ground test facility or spacecraft (although a resistor between the spacecraft and thruster chassis may be used to control this coupling in practice, depending on the specific application). The electrical isolation eliminates the undesirable facility effects that are not present on orbit. This is true whether or not the thruster has conducting pole covers and regardless of the cathode location (external to the magnetic circuit or mounted on the thruster centerline). Biasing to the cathode potential also effectively controls the energy of the ions impacting the pole covers to a known value, which is just 10-15 V more than the bulk plasma existing near the pole faces. This limits the amount of erosion that can occur on these surfaces and allows lifetimes of several tens of thousands of hours to be achieved.
[0023] In a second implementation, the thruster chassis is biased relative to the cathode common using a power supply. This arrangement requires the use of a small power supply in the power electronics, but the added complexity has significant advantages. For example, one advantage is the ability to directly control the energy of the ions impacting the pole pieces, which can essentially eliminate erosion of these surfaces. When coupled with magnetic shielding and long-life cathodes, the lifetime of the thruster could exceed 100,000 hours. A bias power supply would also allow for control of the thruster interactions with the ambient plasma, depending on the conditions in which the spacecraft was flying. The capacity to exercise this control would be especially advantageous in charged atmospheres or other extreme environments.
[0024] Both of the above implementations may be implemented in shielded or unshielded Hall thrusters and in low- or high-voltage Hall thrusters. The control of body currents is important to eliminating ground test facility effects so that the thruster operates in space as it does on the ground.
[0025] Biasing the thruster to the cathode common is relatively simple. In order to establish an electrical connection, a wire can be attached from the chassis to the cathode body (i.e., cathode common), for example either at the thruster itself or in the power electronics. The variable bias approach would require an auxiliary power supply in the power electronics that allows for biasing the thruster body relative to cathode common.
[0026] In both approaches, the thruster chassis is electrically isolated from the vacuum facility ground (as in ground testing) or the spacecraft (for space operation). In an actual spacecraft, a resistor is typically connected between the cathode common and the spacecraft common in order to balance the electron current collected by the solar arrays. The use of either of these techniques provides for an additional level of control of the conditions that the thruster and spacecraft experience.
[0027] The approaches described herein have never been applied to the magnetic layer Hall thrusters described above. Magnetic layer Hall thrusters are distinguished by the use of a specific magnetic field topologies interacting with the confining walls of the discharge chamber (whether conducting or insulating), to produce an extended acceleration layer that is especially conducive to thruster stability and long-life. Magnetic layer Hall thrusters are the only class of Hall thrusters that are actually flown in space. These thrusters typically have ceramic discharge chambers with insulating pole covers, but may also have conducting discharge chambers as described in U.S. Pat. No. 9,453,502, “Metallic Wall Hall Thrusters.”, the disclosure of which is incorporated herein by reference in its entirety. The innovation disclosed herein is entirely unique to this class of Hall thrusters and will greatly increase the life of unshielded Hall thrusters factors of 2-5×), realize the potential of magnetically shielded Hall thrusters (10-100× greater lifetimes than unshielded Hall thrusters), and allow for high-voltage operation.
[0028] Hall thrusters are generally tested in vacuum chambers during their development, instead of in space. The finite pumping speed of the vacuum chamber will maintain a pressure that is still orders of magnitude higher than experienced during operation in space. These differences need to be taken into account when evaluating the performance of a Hall thruster design. Therefore, measurements can be taken of the electrical characteristics of a Hall thruster, for different electrical configurations of the thrust stand and thruster body. By these measurements it is possible to identify the location where electric current is collected on the thruster body, and therefore determine which combination of electrical configurations is most representative of on-orbit conditions.
[0029] For example, a Hall thruster may be tested with non-covered pole pieces, or it may be tested with covered pole pieces. The pole pieces are typically made from a soft magnetic material such as iron, that is also electrically conductive. These pole pieces may be covered with boron nitride, alumina, or other electrically insulating material. During testing, the thruster body and thrust stand are electrically isolated from electrical ground and each other. Electrical insulation is typically verified up to 1000 V at atmosphere and periodically checked during vacuum testing. Different discharge power, voltage and current can be tested for each Hall thruster design. For example, the discharge power may be in the kilowatt range, the voltage in the hundreds of volts range, and the current in the tens of amperes range. The thruster body can be set as grounded or floating. The design of the thruster may be with an internal or external cathode. The voltage and current for the different configurations was tested and it was found that the isolated thruster body collected a higher current with an external cathode.
[0030] During testing, it was verified that the thrust stand collects only a few milli-amperes of current and is not participating in the discharge in any significant way. Isolating the thrust stand, electrically or with external insulation, does not appear to be necessary. During testing, the current collection on the thruster body has been shown to be primarily through the downstream facing surfaces of the non-covered pole pieces. This current collection is dominated by electrons and is the result of high density, high temperature plasma being in contact with the conductor. The following considerations can be made: An insulator has the same zero current boundary condition as a floating conductor; The thruster operates in a similar manner with a floating conductor or the pole covers; The floating potential of the conductor is very similar to the insulator sheath. It can therefore be deduced that the pole cover material can be selected on sputtering considerations alone. Therefore, the material with the higher erosion resistance can be chosen. For example, graphite can be used for the pole covers, since insulating covers have higher erosion rates. The present disclosure describes how a “cathode-tied” configuration is advantageous for magnetically shielded Hall thruster in particular, and Hall thrusters with conducting pole pieces in general.
[0031] Excessive ion energy can result in excessive erosion rates at the poles. The ion energy can be limited by electrically tying the thruster body to the cathode potential, which should limit the increase in ion energy to 10-15 V. Floating the thruster body may be more representative of on-orbit operation, however this configuration may be increasing ion erosion of the poles to unacceptably high values. Therefore, in some embodiments, an advantageous configuration has graphite pole covers, with the chassis body electrically tied to the cathode potential. In this configuration, the cathode floats with regard to the electrical ground during ground testing or the spacecraft common potential on-orbit.
[0032] As understood by the person of ordinary skill in the art, a Hall thruster generally comprises magnetic and electric field generators. For example, a Hall thruster may comprise magnetic pole pieces that generate a magnetic field. The magnetic poles may have a circular cross-section. A gas propellant, such as a noble gas, is emitted from a nozzle. Typically, the anode is also part of, or adjacent to, the gas nozzle. A cathode can be placed in different positions depending on the specific thruster configuration. The cathode and the anode establish an electric field, typically between the magnetic poles. The electric field accelerates the gas ions (for example, Xe), generating thrust. The electron current from the cathode is split in a component towards the anode, and a component neutralizing the ions away from the thruster.
[0033] FIGS. 1 and 2 are schematic diagrams of an exemplary Hall effect thruster ( 100 ), employing a central electron emitting cathode ( 102 ). In other embodiments, the cathode may be positioned away from the center of the circular cross-section. FIG. 1 shows a top view of the thruster and FIG. 2 shows a cross section along points A ( 101 ) of FIG. 1 . The thruster ( 100 ) employs an annular cavity ( 104 ) for ionizing and accelerating gas particles which are ejected from the cavity to develop thrust. A magnetic (B) field is developed radially (from the center to the outer rim) across the open end of the annular cavity ( 104 ), for example with electromagnets. Typically, a magnetic circuit is formed using multiple electromagnetic coils ( 106 A- 106 H), ( 108 ) and a ferrous housing ( 110 ) appropriately constructed to produce the magnetic field as shown in FIGS. 1 and 2 . In the example thruster (TOO), eight outer electromagnetic coils ( 106 A- 106 H) and one larger central electromagnetic coil ( 108 ) are employed although those skilled in the art will appreciate that any combination of coil number and sizes may be employed as necessary to develop the proper magnetic field strength and shape.
[0034] Referring to FIG. 2 , the centrally mounted electron emitter cathode ( 102 ) emits electrons ( 112 ) from an opening around a same level as that of the openings in the annular cavity ( 104 ) (the electrons are illustrated as circular symbols with a negative sign). In other words, in some embodiments, the opening of the cathode lies in the same plane of the opening of the annular cavity ( 104 ). Positioning the cathode in this way reduces keeper sputtering of the cathode ( 102 ), which can increase as the cathode ( 102 ) is extended beyond the plane of the opening of the annular cavity ( 104 ). Performance can be optimized by iteratively adjusting the cathode ( 102 ) end extension position beyond the opening of the annular cavity ( 104 ) and testing each configuration. In this example, the cathode ( 102 ) is disposed in the center of the single large central coil ( 108 ) for developing the magnetic field B ( 114 ).
[0035] The electrons ( 112 ) from the emitter cathode ( 102 ) are drawn to the annular cavity ( 104 ) by a voltage ( 116 ) between the cathode ( 102 ) and at least one anode ( 118 ) disposed at the bottom of the annular cavity ( 104 ). Movement of the electrons ( 112 ) drawn to the annular cavity ( 104 ) is influenced by the magnetic field ( 114 ) such that the electrons become trapped and spiral around the annular cavity ( 104 ). Typically, the anode ( 118 ) is also used to deliver a gas ( 120 ) (e.g. xenon) which flows through it to the bottom of the annular cavity ( 104 ) (illustrated as neutral circular symbols above the anode 118 ). The downstream side of the trapped cloud of electrons ( 112 ) in the annular cavity ( 104 ) forms a “virtual” cathode, an electrical extension of the central cathode ( 102 ). An electric (E) field ( 122 ) is defined from the anode ( 118 ) to this “virtual” cathode in a vertical direction out of the annular cavity ( 104 ). Energized electrons ( 112 ) in the annular cavity 104 also impact and ionize the gas ( 120 ). The gas ( 120 ) ions (illustrated as circular symbols with a positive sign) are driven by the electric field ( 122 ) and expelled out of the annular cavity ( 104 ) imparting a reactive force to the thruster ( 100 ) in the opposite direction. Some additional electrons ( 112 ) from the cathode ( 102 ) are attracted by the expelled gas ( 120 ) ions and drawn out with them, where they neutralize the ion beam.
[0036] It should be noted that the foregoing description of the electron emitter cathode ( 102 ) operating in the Hall effect thruster ( 100 ) is only one example use for the cathode ( 102 ) embodiment of the invention which demonstrates the cathode ( 102 ) disposed in the center of the annular cavity ( 104 ). Other applications and uses will be apparent to those skilled in the art based on the detailed description including key elements of the structure and method of operation of the cathode ( 102 ) as described in the following sections. A typical element of the electron emitter cathode is the rare earth insert which is the source of the electron emission.
[0037] In some embodiments, the cathode ( 102 ) is electrically tied to the thruster chassis through electrical connection ( 190 ). In other embodiments, a power supply can be placed at ( 190 ) to electrically bias the cathode with respect to the thruster body. In some embodiments, pole covers ( 124 ) can be added. For example, the pole covers can be insulating or conducting. In some embodiments, the pole covers ( 124 ) are made of graphite.
[0038] FIGS. 1-2 depict a thruster using outer coils that are arranged around the outside of the discharge chamber. In other embodiments, a single outer coil goes around the outside of the discharge chamber. This configuration changes part of the magnetic circuit.
[0039] In a Hall thruster, the propellant is accelerated by the electric field. The electrons are trapped in the magnetic field and used to ionize the propellant and neutralize the ions in the plume. The magnetic poles can be subject to erosion from sputtering, therefore pole covers are advantageous. Generally, conducting or insulating pole covers can be used. Since insulating covers generally have higher erosion rates, Hall thrusters as described herein can advantageously have, in some embodiments, conducting pole covers, for example made of graphite.
[0040] FIG. 3 illustrates different exemplary cathode configurations. For the different configurations, the cathode is placed at different locations with respect to the separatrix, that is the region of the magnetic fields lines which forms a boundary between the region where an electron is trapped by the magnetic field, and the region where the electron is not trapped. In FIG. 3 , the separatrix is plotted with a thicker line ( 207 , 211 , 217 ). When the external cathode is on the external side of the separatrix ( 205 ), it is easier for the electrons to neutralize the ion beam but more difficult for the electrons to enter the channel between the magnetic poles. When the cathode is on the internal side of the separatrix ( 210 ), it is more difficult for the electrons to neutralize the ion beam but easier for the electrons to enter the channel between the magnetic poles. In the internal cathode configuration (on thruster centerline, 215 ), it is easy for the electrons to neutralize the ion beam and easier for the electrons to enter the channel between the magnetic poles. Generally, about ¾ of the electrons neutralize the beam while about ¼ is collected at the anode.
[0041] During testing, a significant current was measured flowing from thruster chassis to the chamber electrical ground. Since no ground level is present in space, insulating pole covers were applied, which eliminated the greater part of this current. In this way, it was possible to develop a testing methodology that allows object performance testing of the thruster in conditions that are more similar to the actual operating conditions in space. Therefore, the best configuration that allows testing of the thruster was found to be either floating or insulated from ground. Specifically, it was determined that electrically floating the thruster body was the best representation of space conditions in flight. It was also determined that, while small changes occur in the current, between the insulated and floating configuration, there were no significant repercussions with regard to the thruster stability when the floating configuration was used.
[0042] During testing, it was determined, however, that the floating configuration caused erosion at the poles, from ion sputtering. This was due to the fact that the floating level was well below the testing facility ground and the cathode floating potential, which would increase the energy of ions impacting the thruster chassis. This increase in ion energy meant the pole covers would need to be significantly thicker if long-lifetime were to be achieved. Therefore, additional testing was conducted to determine a configuration that would be representative of flight conditions while not adversely affecting the pole erosion rate.
[0043] Specifically, it was found that the ion energy could be limited by tying the thruster body to the cathode potential. In this way, the thruster still floats as the cathode common is floating (therefore being representative of flight conditions), while the excess electron current can be collected at the poles and re-emitted at the cathode. The potential drop from the plasma to the pole will still be greater than with the grounded configuration but is reduced compared to the floating configuration by several tens of volts.
[0044] To test the above configuration and demonstrate the viability of connecting chassis to cathode, the testing set up quantified the current to the thruster chassis as a function of bias voltage, as well as the time-dependent behavior of electrical and plasma properties, and the time-averaged ion velocity. The results validate the hypothesis that tying the thruster chassis to the cathode represents an intermediate case between grounded and floating configurations. This configuration provides for flight-like electrical environments while limiting the ion energy to levels that are expected to be mitigated by pole covers.
[0045] The configuration described in the present disclosure is advantageous for the development of Hall thrusters that have large operating envelopes. For example, the Hall Effect Rocket with Magnetic Shielding (HERMeS) has an operating envelope spanning 300-800 V, 8.9-31.3 A, and 6.25-12.5 kW. However, such an operating envelope needed to be tested for stability. As described above in the present disclosure, the electrical configuration has a high chassis potential which implied enhanced pole erosion. Cathode-tying was implemented as a solution. The cathode-tied configuration was then tested and found to be stable. The cathode-tied operation was also demonstrated to be stable with graphite pole covers. In particular, the cathode-tied graphite cover configuration was compared, during an extended wear test (in the hundreds of hours), with a floating alumina cover configuration.
[0046] It can be noted that, with a grounded chassis, a parasitic current flows from the chassis through to the vacuum chamber to neutralize the ion beam. This current would not be present in orbit. With a floating chassis, the chassis must float to a negative level to reject the hot plasma contacting the poles, which increases the energy of ions impacting the poles. A higher ion energy significantly increases pole erosion. With a cathode-tied chassis, the current collected by the poles is recycled by the cathode, and the ion energy is regulated by the cathode potential.
[0047] In some embodiments, a hollow cathode can be used, for example made of BaO or LaB 6 . BaO has large current throttling capabilities, while LaB 6 is more tolerant to propellant impurities and high current operations. FIG. 4 illustrates an exemplary cathode assembly. The cathode has a hollow cylindrical shape, with the hole ( 400 ) extending longitudinally throughout the structure.
[0048] The following considerations have been discussed also in Ref. [ 9 ]. A simplified diagram of a Hall thruster system on a spacecraft is shown in FIG. 5 . It can be noted that the thruster body ( 410 ) is connected to the spacecraft chassis ground ( 450 ). In some embodiments, the chassis body is biased with a power supply ( 420 ) so as to completely nullify the ion impact energy. Also schematically illustrated are the spacecraft ( 435 ) and its solar array ( 440 ), as well as a hollow cathode ( 425 ), the thruster plume plasma ( 405 ), the thruster anode ( 415 ), the isolation resistor ( 430 ) and a background plasma volume ( 445 ) outside the spacecraft. In FIGS. 6-8 , several elements of FIG. 5 are reproduced.
[0049] In the following, three electrical configurations of Hall thrusters are discussed: 1.) an insulating surface on the pole pieces, and the thruster body electrically tied to the spacecraft chassis (i.e., spacecraft electrical common or sic), 2.) exposed conducting pole pieces and the thruster body electrically tied to the spacecraft chassis, and 3.) exposed conducting pole pieces and the thruster body tied to cathode common. In each of the cases the analysis is for a centrally mounted hollow cathode and generalization of the results to externally mounted cathodes is discussed.
[0050] In FIG. 9 , the testing setups for three configurations are illustrated. In ( 905 ) the chassis is grounded; it should be noted that the parasitic current flowing through the vacuum chamber in the laboratory test to neutralize the beam would not be present in orbit. In ( 910 ) the chassis floats negative to reject the hot plasma contacting the poles. The higher ion energy significantly increases pole erosion. In ( 915 ) the current collected by the poles is recycled by the cathode; the ion energy is regulated by the cathode potential.
[0051] FIG. 10 illustrates a thruster with pole covers ( 1005 ) and without covers ( 1010 , the surfaces will be conducting).
[0052] The solar array electron current collection data, and the current voltage characteristics of the thruster body in the Hall thruster plasma are needed to predict cathode common potentials. Laboratory data was obtained for the magnetically shielded 6 kW H6MS Hall thruster, see Refs. [9,10] with a centrally mounted cathode operating at 300 V and 20 A. With the insulating pole piece surfaces, the ion current to the thruster body was relatively small, about 3 mA. This value may be much higher for externally mounted cathodes, particularly if the hollow cathode is mounted outside the thruster body and cathode ions have a direct line of sight to the body.
[0053] The current voltage characteristic of the thruster with conducting pole pieces, obtained by applying a DC bias to the thruster body, is shown in FIG. 11 . The ion saturation current is about 300 mA, two orders of magnitude larger than with insulating surfaces on the pole pieces. It can be noted that, when the thruster body is connected to chamber ground, 2.5 A of electrons flow from the body to the chamber and help current neutralize the beam. This case is much different than during flight, where the main thrust beam ions must be current-neutralized by electrons flowing through the beam plasma. The floating potential ( 1105 ) of the thruster is about −40 V with respect to the chamber ground.
[0054] With conducting pole pieces, the ion currents to the thruster body are orders of magnitude larger than the electron currents collected by the solar arrays. As an example, a calculation for a notional spacecraft with four 9 kW Hall thrusters shows the solar arrays are expected to collect less than 10 mA of electrons, far less than the 300 mA of ion saturation current for a single 6 kW thruster. With a centrally mounted hollow cathode ( 215 ) or an external hollow cathode whose orifice is inside the magnetic field separatrix ( 210 ), the ion current to a Hall thruster body with insulating pole piece covers will be very small. In laboratory test the ion current to the body was only 3 mA. The ion current to the exposed conducting spacecraft surfaces will be also be very small, since most of such surfaces are behind the thruster exit plane where the plasma density is very low.
[0055] FIG. 6 illustrates a cathode common circuit for a Hall thruster with insulating pole piece surfaces. In this case, the spacecraft chassis ground will float negative with respect to the Hall plume plasma, so that only a portion of the solar array is positive and collects ions. An upper bound on the cathode common voltage is the resistive drop from the solar array electron collection across the isolation resistor, as shown in FIG. 6 as ( 605 ). Proper choice of the isolation resistance will limit the cathode common voltage. For the example above, a 1 kΩ resistor will limit cathode common to less than 10 V as shown in Eq. 1.
[0000] V=IR
[0000] I<I max ≈10 mA
[0000] R=1 kΩ
[0000] V<10V (1)
[0056] A higher resistance will drive the spacecraft chassis ground more negative with respect to the plasma, and increase the cathode common voltage. Because ions are accelerated by sheath electric fields, a negative chassis potential leads to increased ion energies and therefore increased sputter erosion.
[0057] FIG. 7 illustrates a Hall thruster with conducting pole pieces where the current loop ( 705 ) through the thruster body ( 720 ) closes in the plume plasma ( 715 ). The ion currents to Hall thruster bodies with conducting pole pieces will be quite large. In laboratory tests with a centrally mounted cathode the saturation ion current to the body was about 300 mA. In this configuration, the currents to the thruster body dominate, and the thruster body acts like a floating probe as shown in FIG. 7 . The thruster or chassis body is driven negative to repel electrons and balance the thruster-body ion current. Since the electron temperatures are high in the dense plasma above the inner pole piece, the floating potential can be about −40 V with respect to local plasma. The corresponding cathode common voltage, in this case the potential difference between the hollow cathode and the thruster body, can be +30 V.
[0058] During spaceflight, solar array current collection will not play a significant role. The thruster body ion current, about 300 mA, is much greater than the maximum solar array electron collection, which is typically less than 10 mA. For Hall thrusters with externally mounted cathodes where the cathode plume has unobstructed line of sight to the thruster-body metal ( 205 ), the thruster body will still tend to anchor the floating potential. However, in this case the voltages will be lower, of the order of 10 V, since the cathode plasma electron temperature is much lower than the temperature of the plasma next to the inner pole piece. If the isolation resistor ( 710 ) illustrated in FIG. 7 is 1 kΩ or larger, the isolation resistor will act as a voltage probe and will not affect the floating potential or the potential value of the cathode common.
[0059] In the first two configurations (1. an insulating surface on the pole pieces, and the thruster body electrically tied to the spacecraft chassis ground; and 2. exposed conducting pole pieces and the thruster body electrically tied to the spacecraft chassis ground), the thruster body surfaces can float tens of volts negative with respect to the inner pole plasma. In the first configuration with insulating pole piece surfaces, the thruster body potential can be controlled by the value of the isolation resistor. However, the insulating pole piece surfaces will reach floating potentials near in value to those of the thruster body of the second configuration. The negative floating potentials will lead to enhanced sputtering of pole pieces surfaces.
[0060] FIG. 8 illustrates current loops for a Hall thruster with conducting pole pieces and the thruster body at cathode common. This configuration allows the minimization of the voltage difference between the plasma and the pole pieces, thereby allowing decreased or no erosion of the pole pieces. In this third configuration, there are two separate circuits. In the first current loop ( 805 ), electrons are emitted from the hollow cathode ( 810 ), flow through the plasma, land on the pole pieces in the thruster body ( 815 ), and are conducted back to the hollow cathode. Laboratory measurements show that about 1.5 A of electrons are collected by the H6MS thruster body and flow through this circuit, less than 10% of the discharge current.
[0061] The second circuit ( 820 ) is very similar to the first configuration, where the pole pieces had insulating covers and the cathode common voltage is generated by the circuit current flowing through the isolation resistor. The difference is that now none of the ions hitting the thruster contribute to the circuit, compared to the 3 mA of ions in the first configuration. In the configurations without the isolation resistor, the 3 mA of ions cancelled out the same amount of electron current. In the third configuration, since the electron current flowing through the isolation resistor is increased, the spacecraft chassis ground is expected to float more negative with respect to the Hall plume plasma. Additionally, only a portion of the solar array floats positive. An approximate equation for the cathode common voltage is Eq. 2. As noted above, a 1 kΩ isolation resistor will limit the cathode common to 10 V.
[0000]
V
CC
≈
I
max
R
(
V
array
-
V
CC
-
V
HC
V
array
)
2
(
2
)
[0062] In Eq. (2), V CC is the cathode common voltage, I max is the maximum current that the solar array would collect from the plasma if the low side of the array were at plasma potential, R is the resistor isolating power supply from the low side of the solar array, V array is the solar array string voltage, V HC is the voltage drop internal to the hollow cathode.
[0063] In some embodiments, as illustrated in FIG. 2 , the Hall thruster may comprise a thruster body comprising a housing, chassis or body comprising an annular discharge chamber ( 104 ) having an inner wall, the entire inner wall being made of an electrically conductive material and having a rear surface with an aperture ( 191 ) in the inner wall defined therein, said inner wall of said annular discharge chamber having a downstream end ( 191 ), a radially inner surface ( 192 ), and a radially outer surface ( 193 ), wherein said radially inner surface and said radially outer surface respectively radially inwardly and radially outwardly bound said annular discharge chamber.
[0064] The thruster may also comprise an anode/gas distributor ( 118 ) having an anode electrical terminal, said anode/gas distributor situated in said aperture defined in said rear surface of said annular discharge chamber, said anode/gas distributor having at least one inlet configured to receive an ionizable gas ( 120 ) and configured to distribute said ionizable gas for use as a propellant; a cathode neutralizer ( 102 ) configured to provide electrons, said cathode neutralizer having a cathode electrical terminal that can be connected to said anode electrical terminal by way of a power supply ( 116 ) and a switch, said cathode neutralizer and said anode/gas distributor when operating generating an axial electrical field within said annular discharge chamber, and a magnetic circuit having a magnetic yoke, an inner magnetic coil and an outer magnetic coil, said magnetic circuit to be energized by way of a power supply and a switch, said magnetic circuit configured to provide a substantially radial magnetic field across an annular aperture of said annular discharge chamber, said magnetic circuit configured to provide magnetic shielding of said inner wall of said annular discharge chamber from high-energy ions.
[0065] In other embodiments, the Hall thruster may also be unshielded instead of being magnetically shielded. In other embodiments, the annular discharge chamber can be either electrically conducting or insulating. In some embodiments, the chamber may comprise graphite covers ( 124 ) on the magnetic poles. The ferrous housing may also be termed as magnetic pole as it is part of the magnetic circuit when using electromagnets. In some embodiments, the cathode electrical terminal is electrically connected to the thruster body by way of an electrically conducting material, for example a conducting wire or other similar techniques. In some embodiments, the hollow cathode has a cylindrical hollow shape. In some embodiments, the magnetic shielding allows diversion of the high-energy ions away from the inner walls.
[0066] A number of embodiments of the disclosure have been described. Nevertheless; it will be understood that various modifications may be made without departing from the spirit and scope of the present disclosure. Accordingly, other embodiments are within the scope of the following claims.
[0067] The examples set forth above are provided to those of ordinary skill in the art as a complete disclosure and description of how to make and use the embodiments of the disclosure, and are not intended to limit the scope of what the inventor/inventors regard as their disclosure.
[0068] Modifications of the above-described modes for carrying out the methods and systems herein disclosed that are obvious to persons of skill in the art are intended to be within the scope of the following claims. All patents and publications mentioned in the specification are indicative of the levels of skill of those skilled in the art to which the disclosure pertains. All references cited in this disclosure are incorporated by reference to the same extent as if each reference had been incorporated by reference in its entirety individually.
[0069] It is to be understood that the disclosure is not limited to particular methods or systems, which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the content clearly dictates otherwise. The term “plurality” includes two or more referents unless the content clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosure pertains.
[0070] The references in the present application, shown in the reference list below, are incorporated herein by reference in their entirety.
REFERENCES
[0000]
[1] Hofer, R. R., Joins, B. A., Polk, J. E., Mikellides, I. G., and Snyder, J. S., “Wear Test of a Magnetically Shielded Hall Thruster at 3000 Seconds Specific Impulse,” Presented at the 33rd international Electric Propulsion Conference, IEPC-2013-033, Washington, D.C., Oct. 6-10, 2013.
[2] Mikellides, I. G., Katz, I., Hofer, R. R., and Goebel, D. M., “Magnetic Shielding of Walls from the Unmagnetized Ion Beam in a Hall Thruster,” Applied Physics Letters 102, 2, 023509 (2013).
[3] Goebel, D. M., Jorns, B., Hofer, R. R., Mikellides, I. G., and Katz, I., “Pole-Piece Interactions with the Plasma in a Magnetically Shielded Hall Thruster,” HIAA Paper 2014-3899, July 2014.
[4] Hofer, R. R. and Anderson, J. R., “Finite Pressure Effects in Magnetically Shielded Hall Thrusters,” AIAA Paper 2014-3709, July 2014.
[5] Hofer, R. R., Goebel, D. M., Mikellides, L G., and Katz, I., “Magnetic Shielding of a Laboratory Hall Thruster Part II: Experiments,” Journal of Applied Physics 115, 043303 (2014).
[6] Mikellides, I. G., Katz, I., Hofer, R. R., and Goebel, D. M., “Magnetic Shielding of a Laboratory Hall Thruster Part I: Theory and Validation,” Journal of Applied Physics 115, 043303 (2014).
[7] Sekerak, M. J., Hofer, R. R., Polk, J. E., Jorns, B. A., and Mikellides, I. G., “Wear Testing of a Magnetically Shielded Hall Thruster at 2000 S Specific Impulse,” Presented at the 34th International Electric Propulsion Conference, IEPC-2015-155, Kobe, Japan, Jul. 4-10, 2015
[8] Joins, B. A., Dodson, C., Anderson, J, Goebel, D. M., Hofer, R. R., Sekerak, M., Lopez Ortega, A., and Mikellides, I., “Mechanisms for Pole Piece Erosion in a 6-kW Magnetically-Shielded Hall Thruster,” AIAA-2016-4839, July 2016.
[9] Katz, I., Lopez Ortega, A., Goebel, D. M., Sekerak, M. J., Hofer, R. R., Jorns, B. A., and Brophy, J. R., “Effect of Solar Array Plume Interactions on Hall Thruster Cathode Common Potentials,” Presented at the 14th Spacecraft Charging Technology Conference, ESA/ESTEC, Noordwijk, N L, Apr. 4-8, 2016.
[10] Hofer, R., Polk, J., Sekerak, M., Mikellides, I., Kamhawi, H., Verhey, T., Herman, D., and Williams, G., “The 12.5 kW Hall Effect Rocket with Magnetic Shielding (HERMeS) for the Asteroid Redirect Robotic Mission,” AIAA-2016-4825, July 2016.
[11] Hofer, R. R., “Magnetically-Conformed, Variable Area Discharge Chamber for Hall Thruster, and Method,” U.S. Pat. No. 8,407,979 (Apr. 2, 2013).
[12] Manzella, D. H., Jacobson, D. T., Jankovsky, R. S., Hofer, R., and Peterson, P., “Magnetic Circuit for Hall Effect Plasma Accelerator,” U.S. Pat. No. 7,624,566 (Dec. 1, 2009). | A Hall thruster is configured to reduce or eliminate pole erosion by electrically tying the cathode to the thruster chassis body. The electrical connection controls the ion energy hence reducing erosion at the pole. In a different configuration, the cathode is biased by a power supply, allowing further control of the ion energy and the elimination of pole erosion, thus increasing the thruster's operational lifetime. | 1 |
TECHNICAL FIELD
The present invention relates to internal combustion engines; more particularly, to devices for controlling the variable actuation of intake valves in an internal combustion engine; and most particularly, to a variable valve actuation assembly for controllably actuating and deactuating a rocker assembly responsive to a triple-lobed cam in an internal combustion engine between high valve lift and low valve lift modes.
BACKGROUND OF THE INVENTION
Internal combustion engines are well known. In an overhead valve engine, the valves may be actuated directly by camshafts disposed on the head itself, or the camshaft(s) may be disposed within the engine block and may actuate the valves via a valve train which may include valve lifters, pushrods, and rocker arms.
It is known that for a portion of the duty cycle of a typical multiple-cylinder engine, especially at times of low torque demand, valves may be opened to only a low lift position to conserve fuel; and that at times of high torque demand, the valves may be opened wider to a higher lift position to admit more fuel. It is known in the art to accomplish this by providing a special rocker assembly having a switching or latching pin which may be actuated and/or deactuated electromechanically. The rocker assembly includes both fixed peripheral low-lift cam followers that cause low lift of the valve when the pin is disengaged, and a pivotable central high lift cam follower that causes high lift of the valve when the latching pin is engaged into the high lift follower.
Various methods for actuating this type of latching pin are known. For example, see the disclosures of U.S. Pat. Nos. 5,619,958; 5,623,848; and 5,697,333. All of these methods employ individual solenoids, acting through bellcranks or similar structures, as part of an actuation system.
A significant problem for these devices is how to balance the physical size of the solenoid against the force required to actuate the mechanism. The solenoid desirably has rapid response, small size, sufficient stroke and pull-in force, low power requirement, and low sensitivity to voltage and temperature variations; whereas, large size, high pull-in force, and high power are typically required to energize prior art mechanisms.
One approach, disclosed in the above-referenced patents, is to reduce the solenoid force required by using the rotational motion of the rocker assembly inherent in its duty cycle to supply a portion of the actuating force. Typically, the motion of the rocker assembly permits the solenoid to “pull in” to a low air gap wherein high actuating forces can be generated. The solenoid essentially locks itself in the engaged position during a valve lift event (lift portion of the duty cycle), and some other compliant element in the device, such as a bellcrank, resiliently deflects as the rocker returns to the base circle portion of the cam at the conclusion of the lift event. Once the rocker reaches the base circle, the energy stored in the compliant element causes the locking pin to become engaged with the high-lift follower, shifting the rocker assembly to high-lift mode. This configuration requires the holding force of the solenoid in the actuated position to be greater than the force exerted against it by the compliant element; otherwise, the motion of the rocker assembly will overcome the solenoid and increase the magnetic air gap within the solenoid to a point at which the solenoid force becomes too small to actuate the pin, and the rocker then does not shift to high-lift mode.
Another prior art approach, disclosed in U.S. Pat. No. 5,623,897, decouples the force generated by the compliant element from the locking force of the solenoid. One end of the compliant element is “grounded” to the cylinder head, and the solenoid moves the opposite end of the compliant element into a position wherein it may engage the rotational displacement of the rocker assembly. The solenoid simply has to hold the compliant element in that position; it is not required to resist the internal force carried by the compressed compliant element.
The prior art configurations as disclosed have several shortcomings.
First, several of the linkages are fixed with respect to the pivot point of the rocker assembly, which typically is the ball-head of a hydraulic lash adjuster (HLA) supporting the assembly. The vertical length of the HLA may vary in the normal course of operating, and thus the pivot point may also vary in the z (vertical) direction. Further, the vertical and horizontal (x,y) locations of the pivot point must vary inherently from engine to engine as a result of stack-up of manufacturing tolerances. The prior art disclosures do not address practical or self-compensating means for accommodating tolerances in the cylinder head and cam cover.
Second, mechanisms disclosed in the prior art typically employ rotating linkages which may add friction to the force required for actuation and thus increase the force requirements of the solenoid.
Third, none of the disclosed mechanisms, except that shown in U.S. Pat. No. 5,623,897, fully decouples the solenoid force from the compliant element and, therefore, from the pin actuating force. In the disclosure of U.S. Pat. No. 5,623,897, a rotating rocker assembly with a large rocker ratio and large rotational inertia pivots through a relatively large angle in actuating the engine valve. These characteristics add to the force requirements of the solenoid. Further, the solenoid plunger does not act orthogonally to the rocker assembly, resulting in side-loading and friction in the solenoid bearings.
Fourth, in some prior art mechanisms, the point in the rotational cycle of the cam at which the solenoid is energized must be very carefully timed to avoid a phenomenon known in the art as “ejection” wherein the mechanism attempts to engage or disengage the locking pin into or out of the high-lift follower. When the pin is only slightly engaged, it is violently ejected, which can damage the pin or the high-lift follower and which causes a very loud and objectionable noise. Accurate timing of the solenoid energizing can be complex, as the response time of the mechanism may be affected by various operating parameters, such as oil temperature and thus viscosity.
It is a principal object of the present invention to provide an improved variable valve actuation (VVA) assembly wherein a secondary latching mechanism between the solenoid and the primary latching pin in the rocker assembly automatically self-times the engagement of the secondary latching mechanism such that the timing of solenoid energizing and de-energizing is not critical and ejections are prevented.
It is a further object of the invention to provide an improved VVA requiring a low solenoid actuating force and short stroke.
It is a still further object of the invention to provide an improved VVA wherein variation in assembly performance from the stack-up of manufacturing and operating tolerances among the components of the assembly is minimized.
SUMMARY OF THE INVENTION
Briefly described, a variable valve actuation assembly for variably opening of an engine intake valve in either a low-lift or high-lift mode includes a special rocker assembly pivotably disposed in the engine for opening and closing the valve and having a central high-lift cam follower and two peripheral low-lift cam followers, responsive to rotation of a camshaft having low-lift and high-lift lobes engageable with the respective cam followers; a primary latching mechanism including a slidable primary latching pin in the rocker assembly for engaging and disengaging the high-lift follower; a solenoid for causing the primary latching pin to be engaged and disengaged; and a secondary latching mechanism between the solenoid and the primary latching pin to automatically limit engagement and disengagement of the primary latching pin to times in the duty cycle of the camshaft when ejections are not possible.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages of the invention will be more fully understood and appreciated from the following description of certain exemplary embodiments of the invention taken together with the accompanying drawings, in which:
FIG. 1 is an isometric view from above, taken from the camshaft side (camshaft omitted for clarity) showing two variable valve actuation assemblies in accordance with the invention configured for operation of adjacent intake valves of adjacent engine cylinders;
FIG. 2 is an isometric view from above of the VVA assemblies shown in FIG. 1, taken from opposite the camshaft side (camshaft omitted for clarity);
FIG. 3 is an isometric view similar to that shown in FIG. 1, showing the VVA assemblies installed in the head of an engine;
FIG. 4 is a view similar to that shown in FIG. 1, but including a camshaft with high-lift and low-lift cams for one of the VVA assemblies;
FIG. 5 is an isometric view, partially exploded, taken from the VVA side opposite the camshaft side, of secondary latching mechanisms in the VVA assemblies shown in FIGS. 1-4;
FIG. 6 is an isometric view, partially in cross-section, similar to that shown in FIG. 5, showing the relationship of the solenoid mounted on an arbor on the engine and a secondary latching pin in the secondary latching mechanisms shown in FIG. 5;
FIGS. 7 through 10 are cross-sectional elevational views through a VVA taken along plane 7 - 10 in FIG. 4, showing successive stages in one operating cycle of a VVA in accordance with the invention; and
FIG. 11 is another view of FIG. 1 showing cam follower rollers as an alternate embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, an improved dual variable valve actuation (VVA) assembly 10 in accordance with the invention is shown for variable actuation of two separate valves 12 of internal combustion engine 13 . Assembly 10 includes two separate, substantially identical VVA mechanisms 10 ′ sharing a common arbor 14 mountable onto an engine head 94 (as shown in FIG. 3 ). As the two VVA assemblies are substantially mirror images of each other, the following discussion is directed to only one VVA but should be understood as being applicable to both except as noted. Each mechanism 10 ′ includes a rocker assembly 16 and a secondary latching assembly 18 . Rocker assembly 16 is pivotably mounted, preferably by a ball-and-socket joint, on a conventional hydraulic lash adjuster (HLA) 20 and is pivotably connected near a distal end 22 , to the stem of a valve 12 .
Referring to FIGS. 1 and 2 and any of FIGS. 7 through 10, rocker assembly 16 is similar to two-stage rocker assemblies known in the art, as described above. A frame 24 has a spherical socket 26 for pivotably mating with the ball head 28 of HLA 20 . Frame 24 provides a rigid but pivotable bridge between HLA 20 and valve 12 , and is formed having a generally rectangular longitudinal aperture 30 for receiving a high-lift cam follower 32 having a surface for following a high-lift cam lobe as described below. Follower 32 is pivotably pinned at one end by pin 34 in slot 36 formed in frame 24 in communication with aperture 30 . Preferably, a first torsion spring (not shown) is disposed on pin 34 in slot 36 to bias follower 32 upwards into continual contact with its respective cam lobe. Frame 24 further is provided with two rigidly-mounted low-lift cam followers 38 , each having a surface for following a low-lift cam lobe as described below.
At the proximal end 40 of rocker assembly 16 , a primary latching assembly 17 in frame 24 includes a stepped bore 42 slidably receivable of a primary latching pin 44 comprising a latching portion 46 and a trigger portion 48 . Pin 44 is urged away from high-lift follower 32 by a compression spring 50 disposed in bore 42 between frame 24 and trigger portion 48 . When follower 32 is suitably positioned (as shown in FIG. 10 ), portion 46 may be moved axially of bore 42 to engage portion 46 under latching nose 52 of follower 32 , thereby preventing follower 32 from rotating about pin 34 , and transforming rocker assembly 16 into high-lift mode, as described below.
Referring to FIGS. 5 through 10, secondary latching assembly 18 includes a backer frame 54 having a central aperture 56 for receiving a blocker plate 58 therein. Backer frame 54 is provided with bores 60 for receiving pivot screw 62 which is threadedly received in a bore in arbor 14 to pivotably attach frame 54 to arbor 14 . A shim 64 on screw 62 spaces frame 54 a predetermined distance from arbor 14 and supports a second torsion spring 66 engaged by a first tang 68 into arbor 14 and by a second tang 70 onto frame 54 for urging frame 54 pivotably toward rocker assembly 16 . As shown in FIGS. 5 and 6, each siderail 72 of frame 54 is further provided with a stepped bore 74 for receiving a stepped secondary latching pin 76 having a flat boss 78 at one end thereof. A compression spring 80 is disposed in bore 74 around pin 76 for urging pin 76 outwards of bore 74 . Only one bore 74 is used for each frame 54 , but preferably the two bores 74 provided in each frame are mirror images of each other so that a single configuration of frame 54 may be used for either of the assemblies 18 shown in these figures.
Blocker plate 58 is provided with a first bore 82 at an end thereof for receiving screw 62 to pivotably mount plate 58 between bores 60 in frame 54 such that plate 58 can swing through aperture 56 . A third torsion spring 75 is disposed on screw 62 coaxially with plate 58 and is configured conventionally to urge plate 58 rotationally of screw 62 against trigger portion 48 . Plate 58 is further provided with a medial bore 84 for receiving secondary latching pin 76 to rotationally lock plate 58 to frame 54 when so desired.
Frame 54 is further provided with an actuating extension 77 for engaging with the bearing surface 79 of rocker proximal end 40 . Preferably, the bearing surface 81 of extension 77 is included in a plane including the pivot axis 83 of backer frame 54 and bearing surface 79 is a cylindrical arc centered on the center of arcuate pad 85 which interfaces with the stem of valve 12 . As rocker assembly 16 oscillates about HLA head 28 during actuation thereof, surface 79 rotates and slides along surface 81 at a constant radius, and therefore the position of backer frame 54 is unaffected by such action. Further, these geometric relationships make the VVA mechanism virtually insensitive to normal manufacturing, assembly, and operating variations in the size and position of these components.
Arbor 14 is provided with a well 87 for receiving a solenoid 86 having an armature plunger 88 extending toward boss 78 on pin 76 in a direction orthogonal to plane 7 - 10 (FIG. 4 ), which is the actuation plane of assembly 10 ′, and parallel to the axis of rotation of the camshaft. When solenoid 86 is energized, pin 76 is urged toward blocker plate 58 in attempt to enter into bore 84 to lock plate 58 to frame 54 . Such entry is permitted under conditions as described below, wherein bore 74 becomes axially aligned with bore 84 . Where entry is not permitted immediately upon energizing of the solenoid, the energized solenoid acts as a cocked electromechanical spring and will insert pin 76 into bore 84 at the earliest opportunity during the camshaft duty cycle, as described below.
Referring to FIGS. 3 and 4, a camshaft 90 is carried in bearing mounts 92 formed in engine head 94 which positions cam lobes for actuation of valves 12 via rocker assembly 16 . In FIG. 4, the camshaft and cam lobes are shown for only one valve, but it should be understood that identical lobes are provided for each valve having an associated VVA mechanism. Camshaft 90 is provided with a central high-lift lobe 96 , which is followed by central high-lift follower 32 , and a pair of identical peripheral low-lift lobes 98 flanking lobe 96 , which are followed by peripheral low-lift followers 38 .
The conversion of a VVA assembly 10 ′ from low-lift mode (default mode) to high-lift mode is shown sequentially in FIGS. 7 through 10. Beginning with FIG. 7, in default low-lift mode, primary latching pin 44 is disengaged from high-lift follower 32 . Valve 12 is closed. Low-lift cam lobe 98 is engaged on its base circle portion 100 with low-lift follower 38 , and high-lift cam lobe 96 is engaged on its base circle portion 102 with high-lift follower 32 . Solenoid 86 is de-energized and therefore secondary latching pin 76 is disengaged from blocker plate 58 which is pivoted out of alignment by contact with trigger portion 48 at contact point 112 . Thus compression spring 50 which urges primary latching pin 44 out of engagement must be stronger than, and overcome, third torsion spring 75 . To begin the change from low-lift mode to high lift mode, solenoid 86 may be energized at any time during the camshaft duty cycle. Plunger 88 of the solenoid forcibly engages boss 78 (not visible in FIGS. 7-10) but secondary latching pin 76 cannot yet enter bore 84 because of axial misalignment. Secondary latching pin 76 is thus cocked by the energized solenoid to enter bore 84 in the blocker plate to lock the blocker plate to the backer frame 54 as soon as bore 84 becomes coaxially aligned with the pin.
Referring to FIG. 8, a low-lift event is shown in progress. The camshaft has rotated the cam lobes counterclockwise such that eccentric portion 104 of low-lift lobe 98 is engaged with low-lift follower 38 , thereby rotating rocker assembly 16 clockwise about HLA head 28 and opening valve 12 with low lift. Eccentric portion 106 of high-lift lobe 96 is similarly engaged with high-lift follower 32 , but because follower 32 is disengaged from primary latching pin 44 the follower simply pivots on pin 34 without lift effect on valve 12 . Note that bearing surface 108 on trigger 48 is preferably cylindrically arcuate and bearing surface 110 on blocker plate 58 is preferably flat. Comparing the contact point 112 between these two surfaces in FIG. 7 and FIG. 8, it is seen that the surface 108 moves along surface 110 in a combination sliding and rolling motion in response to the clockwise rotation of rocker assembly 16 . The angle of surface 110 with respect to pivot point 83 is such that the relationship of blocker plate 58 to backer frame 54 does not vary with tolerance variations in the cylinder head, an importance advance in the art conferred by an assembly in accordance with the invention. Further, because the change in contact point between the bearing surfaces is eccentric with respect to the pivot point of the rocker assembly, blocker plate 58 is permitted to pivot counterclockwise slightly about pivot axis 83 , bring bore 84 into alignment with pin 76 , which then enters bore 84 at the urging of the previously energized solenoid. Because the pin is small and of low mass, and because bore 84 is aligned with pin 76 by the natural motion of rocker assembly 16 imparted by the engine, solenoid 86 may be very small and relatively weak, thus overcoming the disadvantages of prior art VVA mechanisms as described above. This is an important advantage of a VVA assembly in accordance with the invention.
Referring to FIG. 9, as the low-lift event progresses, the cam lobes have rotated further counterclockwise such that the followers are in contact with the lobes at the point of merger between the eccentric portions 104 , 106 and the base circle portions 100 , 102 of the lobes 98 , 96 . Valve 12 has been closed by the action of a conventional valve spring (not shown), causing rocker assembly 16 to rotate counterclockwise back to its rest position, as shown previously in FIG. 7 . However, blocker plate 58 is not free to also return to its former position because it is now locked to backer frame 54 , as was seen in FIG. 8 . Further, latching portion 46 of primary latching pin 44 is still in slight interference with latching nose 52 . Therefore, the locked unit of backer frame and blocker plate is pivoted clockwise about axis 83 against second torsion spring 66 , cocking the primary and secondary latching mechanisms for engagement of primary latching pin 44 with latching nose 52 at the earliest opportunity.
Referring to FIG. 10, the low-lift event is completed and rocker assembly 16 is locked in high-lift mode by primary locking pin 44 . The cam lobes have rotated slightly farther than as shown in FIG. 9, onto their respective base circle portions, and high-lift follower 32 has pivoted farther clockwise about pivot pin 34 , bringing latching nose 52 into latching alignment with latching portion 46 . Second torsion spring 66 is stronger than compression spring 50 and immediately urges primary latching pin 44 into engagement with latching nose 52 , compressing spring 50 and completing the conversion of the rocker assembly from low-lift mode to high-lift mode. During the next revolution of the camshaft, the high-lift eccentric of lobe 96 will cause rocker assembly 16 to rotate through a greater angle than in the previous duty cycle, thereby opening valve 12 wider (higher lift) than in its previous opening.
Both primary latching pin 44 and secondary latching pin 76 will remain engaged as long as solenoid 86 is energized; the assembly will thus remain in high-lift mode. To shift back to low-lift (default) mode, the solenoid may be de-energized at any point. It will be seen that there is no shear force on secondary pin 76 while either a low-lift or high-lift event is in progress (eccentric lobe portions are engaged). Thus pin 76 is free to engage or disengage with bore 84 at any such time. De-energizing the solenoid during the high-lift event permits compression spring 80 to eject pin 76 from bore 84 ; however, primary latching pin 44 remains engaged with latching nose 52 because of shear force therebetween. When the lobes return to their base circles and such shear force is removed, compressed spring 50 immediately urges primary latching pin out of engagement with nose 52 . Blocker plate 85 is free to pivot away, and the assembly is returned to the default low-lift mode shown in FIG. 7 .
It is an important advantage of a VVA assembly in accordance with the invention that the engagement of the primary latching pin with the high-lift follower necessarily occurs at the beginning of the base circle lobe engagement, at a point of no shear force between the pin and the follower. Thus, ejections of the primary latching pin, as are well known in the prior art, are rendered impossible. Further, because the secondary latching pin engages the blocker arm only when they are axially aligned, which occurs only during the lift portion of a low-lift duty cycle, the solenoid need be only strong enough to displace the secondary pin axially a short distance.
While the invention has been described by reference to various specific embodiments, it should be understood that numerous changes may be made within the spirit and scope of the inventive concepts described. For example, high-lift and low-lift cam followers 32 , 38 are shown as sliders herein but some or all of the followers may instead be provided as rollers rotatably mounted to frame 24 within the scope of the invention. For example, in FIG. 11, roller 38 ′ is shown instead of slider 38 . Accordingly, it is intended that the invention not be limited to the described embodiments, but will have full scope defined by the language of the following claims. | A variable valve actuation assembly for actuation of an engine intake valve between low-lift and high-lift modes. The VVA assembly includes a special rocker assembly having a pivotable central high-lift cam follower and two peripheral low-lift cam followers; a camshaft having low-lift and high-lift lobes engageable with the respective cam followers; a primary latching assembly including a slidable primary latching pin in the rocker assembly for engaging and disengaging the high-lift follower; a solenoid for causing the primary latching pin to be engaged and disengaged; and a secondary latching mechanism between the solenoid and the primary latching pin to automatically limit engagement and disengagement of the primary latching pin to times in the duty cycle of the camshaft (during lift events) when ejections of the primary latching pin are not possible. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to implantable medical devices. More specifically, the present invention relates to battery-powered implantable devices that receive energy for recharging the battery from an external source. Still more particularly, the invention relates to systems for transmitting energy from an external source to an implanted medical device and for transmitting data between an implanted device and external apparatus.
2. Description of the Relevant Art
Implantable medical devices, such as pacemakers and defibrillators, typically are powered by a battery that is incorporated within the device. Non-rechargeable batteries are commonly used to power the implanted devices. Non-rechargeable batteries, however, have a limited life and thus surgery, including its associated risks, discomfort and cost, is necessary to replace an implanted device once its battery is drained. Because of limited life and other undesirable consequences of using non-rechargeable batteries, the use of rechargeable batteries is desirable. Whereas operational life of an implanted device incorporating a non-rechargeable battery was limited to the duration of the original battery charge, an implanted device using a rechargeable battery can function for significantly longer periods given that the batteries can be recharged repeatedly.
One technique for recharging an implanted devices battery involves transcutaneous energy transmission, a technique which allows non-invasive battery charging. Using transcutaneous energy transmission, such as described in U.S. Pat. No. 5,411,537, an alternating current (AC) in an external primary coil of wire creates a magnetic field which, in turn, induces an AC electrical current in a secondary coil of wire that is housed within the implanted medical device. Charging energy is thus transmitted in the same manner as between the primary and secondary coils of a transformer. The alternating current induced in the implanted secondary coil is then rectified and regulated to provide direct current (DC) power for charging the medical device's battery.
Transcutaneous energy transmission, although generally safe and reliable, is not without certain shortcomings. For example, the efficiency of transcutaneously inducing a current in the implanted coil is detrimentally effected if the internal and external coils are not properly aligned or oriented, or if the distance between the external and internal coils is too great. Because there is no direct physical connection between the external charger and the implanted device to provide feedback, ascertaining whether transmission efficiency is maximized or whether the battery has become fully charged is problematic.
Also, as mentioned previously, transcutaneous energy transmission relies upon a magnetic field to induce an AC current in the implanted coil. At the same time, the alternating magnetic flux generated by the AC current may induce eddy currents in the medical device's metal housing and in the metal casings of various components internal to the implantable device. The magnitude of these eddy currents is a function of the frequency and magnitude of the magnetic flux. Eddy currents cause a temperature increase in the metal components in which the current is conducted. If too great, the temperature increase in the implanted device caused by eddy currents can damage the surrounding body tissues. A high charging current, moreover, creates large temperature rises, thereby increasing the risk of harm to surrounding tissues.
Another known recharging technique uses direct electrical connections between an external power source and an implanted receptacle. For example, U.S. Pat. No. 4,941,472 (Moden, et al) describes an implanted electrical access port to provide a receptacle for receiving needle electrodes. The electrical access port in Moden is electrically interconnected to an implanted medical device. L-shaped needle electrodes of Moden are inserted through the patient's skin and body tissue and inserted into opposite ends of the access port. A center conduit in the needle electrode is made of a conducting material and, except for the needle's tip, is surrounded by an insulating material. The Moden needle electrodes mate in the access port with brush-shaped contact assemblies. Because of the shape of the needle electrode in Moden (L-shaped), insertion of the needle electrodes is cumbersome. Further, as best shown in FIGS. 4 and 5 of Moden, the needles must be inserted into the access port completely and with a small angular tolerance. That is, it is easily possible to insert Moden's needle electrodes into the access port at such an angle that the electrode's tip will not mate with the brush-shaped, contact assembly. In this event, the required electrical connection would not be made. Also, Moden contemplates positioning the access port apart from the implanted medical device, thus requiring two surgical sites in order to implant the entire system.
U.S. Pat. No. 5,205,286 (Soukup, et al.) discloses a subcutaneous data port that provides a plurality of conductive ports for receiving needle electrodes. Multiple needle sticks are required with the Soukup device in order to mate the needles with all of the conductive ports, thus potentially increasing discomfort to the patient. Soukup also contemplates implanting the port separately from the implanted therapeutic device such that incisions in at least two locations are required.
Thus, there remains a need in the art for a system that overcomes these and other problems associated with existing systems for providing recharging current to implanted devices. A means for providing direct electrical connection between the external charging device and the implanted device would eliminate alignment concerns, eliminate the potential for tissue damage caused by the eddy currents generated by transcutaneous energy transmission, eliminate the need for inclusion of internal charging circuitry within the implanted device, and would provide a direct connection between the external charger and battery so as to provide feedback information on the status of battery charging. It would be desirable to provide a system for making a direct electrical connection between an external charging device and an implanted device which minimizes the number of surgical sites required. In particular, it would be desirable to construct an implantable medical device (a pacemaker or defibrillator, for example), that itself includes at least one receptacle, for receiving needle electrodes for recharging a battery in the medical device. It would also be desirable to minimize the number of needle electrodes required to make the required electrical connections, yet at the same time allow for multiple conductors to connect to the implantable device. It would be preferable if all the electrical connections could be made by means of a single needle. It would be further advantageous to provide direct electrical connections to an implantable medical device for, not only recharging the batteries in the medical device, but also other electrical functions such as transferring data to and from the medical device. Despite the substantial advantages that would be afforded by such a system, to date no such system has been developed.
SUMMARY OF THE INVENTION
A connector system and method for providing a direct electrical connection to an implanted medical device is disclosed to recharge batteries, reprogram memory, and/or transmit data. The connector apparatus includes a needle-like male connector in conjunction with an implantable female receptacle connector that is attached to the implanted medical device and contains a self-resealing septum entry port. The needle-like male connector electrode pierces through skin and body tissues and inserts through the septum entry port of the female receptacle connector. The female receptacle includes a receptacle chamber that is densely packed with a plurality of randomly intertwining thin, flexible, and conductive metal fibers that allow easy male connector electrode insertion and electrical contact, while also providing a wide tolerance mating target. The self-resealing septum forms a seal around the entry port of the female receptacle through which the needle connector passes. Upon extraction of the needle connector from the receptacle, the septum reseals the hole through which the needle connector was extracted. The receptacle connectors are preferably housed within the implanted medical device but can be implanted at a remote location from the medical device with properly insulated conductors that connect the receptacles and the medical device. Using two needle connectors, one a positive polarity electrode and the other negative polarity, and two proper polarity mating receptacles, a direct electrical completed circuit path to the implanted device can be made which can be used to recharge an internal battery of the implanted medical device.
One or more coaxially disposed conductive elements may be incorporated onto the needle connector, each conductive element is insulated from other conductive elements by a sleeve of insulating film. A needle connector with multiple conductive elements can be used to recharge the medical device's battery, reprogram memory, extract data stored in memory in the medical device and the like. In this embodiment, the female connector is a multi-chambered receptacle including a separate chamber or receptacle for electrical connection to each corresponding conductive element of the needle connector. The multiple receptacles of this embodiment are coaxially aligned in a stacked relationship. Each receptacle is insulated from the others by means of separate self-resealing septums for each receptacle. Upon needle connector insertion, each conductive element in the needle connector makes electrical contact only with the metal fibers in the respective mating receptacle.
A grounding plate may be used in conjunction with one single polarity connector pair to eliminate one of the two needle penetrations required to provide the completed circuit path for battery recharging. The needle connector may provide a positive or negative polarity terminal and the grounding plate, which is placed in contact with or attached to the surface of the patient's skin in proximity to the implanted device, provides the necessary opposite polarity terminal. The metal housing of the implanted medical device, which is required to be internally connected to one of the internal battery terminals (either permanently or through a switched connection), electrically couples via the conductivity of the patient's body tissue to the grounding plate thus completing the required circuit path.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings in which:
FIG. 1 is a schematic block diagram showing the apparatus and system of the present invention for making a direct electrical connection between an external device and an implanted device using needle electrodes and receptacles to recharge batteries within the implanted device;
FIG. 2A is a perspective view showing the implantable receptacle of FIG. 1 for receiving a needle electrode;
FIG. 2B is a cross-sectional view of the receptacle of FIG. 2A;
FIG. 2C is a perspective view showing a first alternative embodiment for the implantable receptacle of FIG. 2A:
FIG. 2D is a perspective view showing a second alternative embodiment for the implantable receptacle of FIG. 2A;
FIG. 3 is an enlarged cross-sectional view of a needle electrode for insertion into the receptacle of FIG. 2A;
FIG. 4 is a schematic block diagram showing an alternative embodiment of the invention in which the receptacles are implanted separately from the implanted medical device;
FIG. 5 is a schematic block diagram showing a second alternative embodiment for charging a battery within an implantable medical device using a needle electrode and a grounding plate;
FIG. 6 is a schematic block diagram showing another alternative embodiment of the present invention having a bipolar needle electrode and receptacle to recharge a battery within an implanted medical device;
FIG. 7 is a perspective view, similar to FIG. 2A, showing an implantable receptacle for receiving the bipolar needle electrode of FIG. 6;
FIG. 8 is an enlarged cross-sectional view of the bipolar needle electrode of FIG. 6;
FIG. 9 is a schematic block diagram of another embodiment of the invention having a multi-polar needle electrode for recharging a battery, reprogramming memory or accessing internal data in an implanted medical device;
FIG. 10 is an enlarged perspective view of the implantable receptacle of FIG. 9 for receiving a multi-polar needle electrode with three conductors; and
FIG. 11 is an enlarged cross-sectional view showing the multi-polar needle electrode of FIG. 9 including three conductors for mating with the receptacle of FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, a system consistent with a preferred embodiment includes an external charger 29 connected to an implanted medical device 26 through a pair of needle connectors 30a and 30b. Needle connector 30a connects to the positive terminal of external charger 29 via conductor 31 and needle connector 30b connects to the negative terminal of external charger 29 via conductor 33. Implanted device 26, which may be a defibrillator or pacemaker for example, includes housing 25, header 27, receptacles 10, internal battery 28 and conductors 20 for interconnecting receptacles 10 and battery 28. Housing 25 preferably is made of titanium or other biocompatible material and includes an interior chamber for housing battery 28 as well as other conventional circuit components (not shown). Header 27 provides an access area for external connection to implanted medical device's internal circuitry and is made of epoxy for example. Receptacles 10 are preferably embedded in header 27.
As will be explained in greater detail below, receptacles 10 are sealed by self-resealing septums 12. The needle electrodes 30a, 30b pierce the patients skin 300 and are inserted through the underlying tissue and through septums 12 and into receptacles 10 of implanted device 26. Receptacles 10 provide electrical connectivity between the needle electrodes 30a, 30b and conductors 20 which connect to the internal battery 28. In the preferred embodiment thus described, receptacles 10 are housed within the implanted medical device 26, as opposed to being implanted remotely from the device. Housing the receptacles 10 within the implanted device 26 advantageously allows the entire system for making direct electrical connection to be implanted at a single surgical site.
Referring now to FIGS. 2A, 2B, and 3, needle electrode 30 and receptacle 10 of the present invention are described in detail. The receptacle 10 includes a self-resealing septum 12 covering a non-conductive receptacle housing 14 which is densely packed with a plurality of randomly intertwining thin, flexible, and conductive metal fibers (analogous to the consistency and texture of a steel wool pad) 16, as best shown in the cross sectional view in FIG. 2B. Receptacle housing 14 is preferably is cylindrical having longitudinal axis L, bottom 15 and sidewall 17 that extends from bottom 15 to upper edge 19. Bottom 15 and sidewall 17 are formed of polyurethane or another biocompatible insulative material. Other shapes and geometries are possible for receptacle 10. For example, there is shown in FIG. 2C a receptacle 10a including a receptacle housing 14a having a generally frustoconical shape and having a circular cross section that tapers from a larger cross sectional area at end 19a to a smaller cross sectional area at the bottom surface 15a. Alternatively, in FIG. 2D a receptacle 10b is shown to include a receptacle housing 14b having a generally rectangular cross section. Receptacle 14b includes a rectangular shaped self-resealing septum 12a at end 19b of receptacle housing 14b. The advantages of these shapes will be addressed in the discussion below.
Referring again to FIGS. 2A and 2B, a conducting member or electrode 18 is attached to and extends through sidewall 17 and contacts the metal fibers 16 or is connected to an inner conductor (not specifically shown) which may be included to ring the inner wall of the cavity to promote conductivity to the fibers. A conducting wire 20 is bonded to conducting member 18, thereby providing an electrical connection between metal fibers 16 and the internal battery 28 of the implanted medical device 26.
Self-resealing septum 12 is made of a nonconducting, biocompatible, elastometric, and self-resealable material such as silicone rubber or polyurethane. The septum 12 provides a closure and seal for receptacle housing 14 to prevent body fluids from entering the receptacle housing 14 or allowing the metal fibers to escape from receptacle housing 14. Septum 12 is attached to the receptacle housing 14 using silicone rubber, polyurethane adhesive or the like. As the needle electrode 30 is inserted through the septum 12, the septum advantageously forms a seal around the electrode substantially preventing body fluids from entering the receptacle housing 14. As the needle is withdrawn from the receptacle 10, the septum 12 automatically reseals the hole from which the needle electrode 30 was extracted.
Referring to FIG. 3, the preferred construction of the needle connectors 30a and 30b is shown with reference to connector 30a, recognizing that connector 30b is substantially the same. Needle connector 30 includes central conducting needle 32 surrounded by an thin insulation layer 34. Central conducting needle 32 is substantially circular in cross section and includes a sharp tip 32a for piercing skin, body tissues, and septum 12. Further, it is preferred that needle electrode 30a be substantially straight. The material from which central conducting needle 32 is made may include "300 series" stainless steel. As shown, only the tip 32a of the needle connector 30a is exposed; the remaining portion of needle connector 30a is covered by a thin layer of insulation 34, preferably polyimide, parylene or other bio-compatible, insulating material that has a thickness of approximately 0.1 to 1 mils.
The conductive metal fibers 16 substantially fill the internal volume of the receptacle housing 14. The fibers are preferably made of MP35N alloy, platinum, or other non-corrosive, bio-compatible conducting material. Although the metal fibers 16 include many different shapes and configurations, the fibers are preferably circular in cross section, and approximately 1 mil in diameter. The fibers 16 are packed within receptacle housing 14 with sufficient density to ensure an adequate electrical contact between the fibers and the exposed conducting tip 32a of the needle electrode 30a. At the same time, however, there is sufficient space between fibers to allow needle electrode 30a to be inserted easily through the volume of metal fibers.
As mentioned above regarding the system shown in FIG. 1, the receptacle 10 is implanted within the body as a component of implantable device 26 and receives the needle electrode 30 that is inserted through the skin and body tissues. The needle electrode 30 pierces the septum 12 and is further inserted into the receptacle housing 14. The needle electrode 30 may be inserted through the interior of receptacle housing 14 until the needle tip 32a contacts the bottom 15 of receptacle housing 14. Once the needle electrode 30 makes contact with bottom 15, resistance from further insertion of the needle provides tactile feedback to the doctor or technician indicating that the needle has been fully inserted into the receptacle 10. Other feedback methods could be employed to verify proper insertion and connection to a partially depleted internal battery, such as by using an external voltmeter connected to the connector.
Referring to FIGS. 2A and 3, needle electrode 30a may be inserted at the center C of septum 12. However, the construction of receptacle 10 advantageously allows needle insertion at any other point on septum 12. For example, needle insertion along line N will permit an adequate electrical connection between needle electrode 30a and conducting member 18. The density of metal fibers 16 within receptacle housing 14 ensures electrical conductivity between various adjacent conductive fibers 16 and thus, between the tip 32a of needle electrode 30a and conducting member 18. Consequently, needle electrode 30a may be inserted along a line parallel to longitudinal axis L or at a myriad of other angles less than 90°. Preferably, however, the needle is inserted at an angle between 0° and 30° as measured relative to longitudinal axis L. Moreover, the needle electrode 30a need not be inserted at only one point on septum 12, nor at any one angle. Further, tip 32a need not contact bottom surface 15 for an electrical connection to be made. Tip 32a need only be inserted far enough into the receptacle cavity such that it is not contacting body tissues and is contacting at least one conducting fiber 16 somewhere within receptacle housing 14. Thus, the design of receptacle 10 which permits the insertion of needle electrode 30a at any point on the surface of septum 12 at virtually any angle provides substantial tolerance with respect to making a direct electrical connection during insertion of needle connector 30a.
Alternative embodiments of the invention are shown in FIGS. 4-11. In describing these embodiments, like reference numerals will be used to refer to components or elements that are identical or substantially the same as those previously described.
Referring now to FIG. 4, receptacles 10 are shown as separate components and are implanted remotely from the implanted medical device 26. Receptacles 10 that have no conductive materials exposed to the patient's body tissues are electrically connected to the implanted medical device 26 by conductors 20 which terminate on terminals 23 in header 27. Terminals 23 are connected to the internal battery 28 via conductors 21. An external charger 29 is connected to the needle electrodes 30a, 30b through conductors 31 and 33. To electrically interconnect external charger 29 to implanted device 26, needle electrodes 30a, 30b are inserted through the skin 300 into receptacles 10. Implanting receptacles 10 remotely from implanted device 26 may be advantageous when, for example, implanted device 26 is deeply implanted or implanted at an angle at which needle insertion would be difficult. It is preferable to avoid sharp edges on the surface of implantable devices exposed to body tissue. Thus, generally round receptacle housing shapes such as those shown in FIGS. 2A and 2C are preferred over the rectangular shape of the housing in FIG. 2D when the receptacles are implanted separate from the implanted device 26.
In the embodiments of the invention described with reference to FIGS. 1 and 4, two needles are required, one serving as the positive electrode and a second as the negative electrode. An alternative embodiment is shown in FIG. 5 in which a single needle electrode 30a is used to provide either the positive or negative electrode and a ground plate is used to connect the return terminal. In this instance, the negative terminal 28a of the battery 28 is connected to the metal housing 25 of implanted medical device 26 through conductor 28b. Thus, the external surface of the medical device 26 is at the same electrical potential as the negative terminal of internal battery 28. The negative terminal 29a of the external charger 29 is connected through conductor 33 to a grounding plate 75 which is placed in contact with the skin 300. The negative electrode current path identified as dashed line 76 is completed through body tissue between grounding plate 75 and the metal housing of the implanted medical device 26. This embodiment has the advantage of requiring only one needle penetration to provide a complete electrical circuit path between external charger 29 and implanted device 26 and also allows the use of a less complicated connection system over the bipolar connector system which is described later.
Referring now to FIG. 6, another alternative embodiment includes a bipolar needle electrode 62 connecting external charger 29 to implanted device 26. Bipolar needle electrode 62 penetrates the skin 300 and mates with dual-chamber receptacle 40 which includes coaxially aligned and stacked receptacles 42, 52. Receptacle 42 connects to the negative terminal of internal battery 28 through conductor 51 and receptacle 52 connects to the positive terminal of the internal battery 28 through conductor 61. Conductor wires 71 and 72 are attached to the conductor electrodes of bipolar connector 62 at the opposite end 65 of the needle connector that pierces and penetrates the skin and implanted receptacles. Conductor 71 connects the bipolar needle connector 62 to the positive terminal 29b of external charger 29, and conductor 72 connects the needle electrode 62 to the negative terminal 29a of external charger 29.
Referring now to FIGS. 7 and 8, the receptacles 42, 52 and bipolar needle 62 are described in greater detail. The bipolar receptacle connector 40 shown in FIG. 7 includes two receptacles 42, 52 of similar construction to receptacle 10 shown in FIGS. 2A and 2B. Receptacles 42, 52 include septums 44, 54, respectively, which are identical to septum 12 described previously. Receptacle 42 includes a non-conductive receptacle housing 46 sealed at its upper end by septum 44 and is filled with conducting metal fibers 16 previously described. A conductor 51 connects to the metal fibers 16 through a conducting member 50. Conducting member 50 is identical to electrode 18 previously described and is attached to the wall of the receptacle housing 46 and protrudes into the internal volume of the receptacle housing 46 making contact with the metal fibers 16. Receptacle 42 has no bottom and is stacked on top of, and attached or bonded to, receptacle 52. Because receptacle 42 may include no bottom surface, the receptacle housing shapes of FIGS. 2A (cylindrical) and 2D (rectangular) are preferred for stacking than the frustoconical shape of FIG. 2C.
Receptacle 52 includes septum 54 covering a receptacle housing 56 with bottom 57 and is filled with conducting fibers 16. A conductor 61 is coupled to the fibers 16 through a conducting electrode 60 which is identical to electrode 50. With this structure, a needle conductor 62 that is inserted through septum 44 may pass through receptacle housing 46 and through septum 54 and into receptacle housing 56 before making contact with the bottom surface 57 of receptacle housing 56. Septum 54 prevents metal fibers 16 in receptacle 42 from contacting the metal fibers 16 in receptacle 52 and thereby insulates the fibers 16 in receptacle housing 46 from those in receptacle housing 56.
Bipolar needle electrode 62 (FIG. 8) contains a central conducting needle 64 coaxially surrounded by an insulating film 66. Tip 63 of conducting needle 64 is exposed (i.e., not covered by insulating film 66). A conducting film 68 made preferably of platinum covers the upper portion of insulating film 66 beginning a distance D from the tip 63. Film 68 has a thickness of approximately 2 to 10 microns in order to provide a very thin conductive layer to allow ease of needle penetration. A second insulating film 70 surrounds conducting film 68, except for an exposed end portion 67. Insulating film 66, 70 may include materials such as polyimide or parylene. The distance D is selected to be at least as great as the longest length that the needle would be able to penetrate into receptacle 52 when needle connector 62 is inserted at any angle. Selecting D in this manner ensures that the exposed portion 67 does not extend into receptacle 54 even when the tip 63 of needle electrode 62 contacts the bottom surface 57 of receptacle housing 56 at any angle. Thus, when the needle electrode 62 is fully inserted into receptacles 42, 52 (i.e., with tip 63 contacting bottom surface 57), the exposed conducting tip 63 and exposed end portion 67 contact metal fibers 16 in receptacles 42, 52, respectively, thereby completing the desired electrical paths to conductors 61, 51. Insulating film 70 extends up the outer surface of the needle connector 62 with sufficient length to electrically isolate the outer conductor portions of needle connector 62 from body tissue that the needle connector passes through in order to prevent short circuiting. As with the needle receptacle system of FIG. 1, bipolar needle electrode 62 need only be inserted into receptacle 40 to the extent that tip 63 of needle 64 contacts the metal fibers 16 in receptacle 52 and tip 63 is fully inserted into receptacle 52 such that short circuiting to metal fibers 16 in receptacle 42 does not result. When this occurs, exposed portion 67 of conducting film 68 will be in contact with metal fibers 16 in upper receptacle 42. Thus, tip 63 need not contact bottom surface 57; rather tip 63 need only contact at least one of the metal fibers 16 and no metal fibers in receptacle 42 to make the required electrical connection. Likewise, exposed end portion 67 need only contact one metal fiber 16 and not be in contact with any body tissues. Substantial tolerance is thus provided by the present invention for ensuring proper connection between dual receptacle 40 and needle electrode 62.
Referring now to FIGS. 6 and 8, conductor 71 connects to conducting needle 64 and conductor 72 connects to conducting film 68. Bipolar needle electrode 62 thus contains two conductors 64 and 68 arranged coaxially with 68 surrounding 64. Conducting needle 64 can be used as the positive electrode and conducting film 68 can be the negative electrode, or vice versa. Bipolar electrode 62 allows two conductors to be inserted through the skin and to make a direct electrical connection to an implanted medical device using a single needle and requiring only one needle insertion.
The embodiments described above have particular utility when used to connect an external charger to a rechargeable battery that is internal to an implanted medical device. This is typically accomplished by means of two electrical connections (i.e., one positive and one negative terminal). Other functions requiring electrical connection may require connection of more than two conductors.
An embodiment of the present invention providing multiple direct connectors is shown in FIG. 9 and generally includes implantable device 26, external unit 43, and multipolar needle electrode 112 for interconnecting implantable device 26 and external unit 43. As shown in FIG. 9, implantable device 26 includes housing 25 and header 27. Multi-chambered receptacle 80 is disposed in header 27. Housing 25 contains battery 28, microprocessor or control circuitry 136, switches 134, telemetry circuitry 132, and memory 130. Memory 130 may include random access memory (RAM), read only memory (ROM), electrically erasable read only memory (EEPROM), and the like. In general, microprocessor 136 controls operations of the implanted medical device including switches 134 and telemetry 132 which may be used to communicate non-invasively with the microprocessor. Switches 134, interconnected with needle electrode 112 by means of conductors 91, 101, 111, is operable to selectively interconnect battery 28, memory 130 or any other internal circuitry (not shown) to an external unit 43 via multipolar needle conductor 112 and conductors 135, 136 and 137.
The system for making direct electrical connections between external device 43 and implanted medical device 26 shown in FIG. 9 may be employed not only to charge the battery internal to the implantable medical device, but also to provide a direct electrical link with the implantable medical device for purposes such as reprogramming memory or accessing data. It would be desirable, for example, to correct a software code error that has been identified after a device has been implanted or to add a newly developed software feature to an implanted device. Downloading new software to the implanted medical devices reprogrammable memory 130 via switches 134 is accomplished using multi-polar needle electrode 112. EEPROM and RAM integrated circuits are provided in many different configurations requiring different numbers of conductors for reprogramming the devices. Although the needle connector 112 shown in FIG. 9 contains three conductors, one of ordinary skill in the art will recognize that more than three conductors may be necessary or desirable to reprogram a reprogrammable memory circuit of a particular implantable medical device and that more than three conductors can be incorporated into a multi-polar needle electrode 112. The connector could also be used to read data stored in the devices reprogrammable or non-reprogrammable memory.
Telemetry circuitry employed by the implanted device could be used to communicate with the processor 136 to control the state of the switches 134 to route the external connections to their proper internal destinations such as for recharging the battery, reprogramming memory, or reading data.
Referring now to FIGS. 10 and 11, multi-chambered receptacle 80 comprises three receptacles 82, 92 and 102 that are interconnected at their ends and coaxially aligned along axis L. Receptacle 82 includes a bottomless receptacle housing 86 sealed at its upper end by a self-resealing septum 84. Metal fibers 16 substantially fill the internal volume of receptacle housing 86, and a conductor 91 connects to the metal fibers 16 through conducting electrode 90. Similarly receptacle 92 includes a bottomless receptacle housing 96 sealed at its upper end by a self-resealing septum 94 and substantially filled with conducting fibers 16. Septum 94 separates and insulates the metal fibers 16 in receptacle 82 from those of receptacle 92. A conductor 101 connects to the metal fibers 16 in receptacle 92 through conducting electrode 100. Finally, receptacle 102 comprises a receptacle housing 106 having bottom 107. Receptacle housing 106 is sealed at its upper end by a self-resealing septum 104 and is substantially filled with conducting metal fibers 16. A conductor 111 connects to the metal fibers 16 in receptacle 102 through conducting electrode 110. Septum 104 separates and insulates the metal fibers 16 in receptacle 92 from those in receptacle 102. Each septum 84, 94, 104 is preferably identical to septum 12 previously described.
Multi-polar needle electrode 112 adapted for insertion into multi-chambered receptacle 80 is shown to comprise three conducting elements 114, 118, and 122 each conductor separated by an insulators 116, 120, and 124, respectively. Conducting element 114 comprises a central conducting needle identical to the needle connectors of FIGS. 3 and 8. Conducting needle 114 includes an exposed tip 113. Conducting elements 118 and 122 comprise conducting film similar to the conducting film 68 of FIG. 8. Insulating films 116, 120, 124 comprise insulating films of the same construction as the insulating film 66 in needle electrode 62 of FIG. 8. Exposed portions or segments 117, 121 of conducting films 118, 122 provide contact with metal fibers 16 in cans 96, 86, respectively. The lengths of each conductor and insulator are such that with the needle electrode 112 fully inserted and contacting the bottom surface 107 of receptacle 102, the exposed tip 113 of electrode 114 makes contact with metal fibers 16 in receptacle 102, the exposed conducting portion 117 of electrode 118 makes contact with metal fibers 16 in receptacle 92, and the exposed conducting portion 121 of electrode 122 makes contact with the metal fibers 16 of receptacle 82. As shown in FIG. 11, distance D1, which is the distance from the tip 113 to the exposed portion 117 of conducting film 118 ensures that the exposed portion 117 does not enter receptacle 102, but does enter receptacle 92 when the needle electrode 112 is fully inserted with its tip 113 contacting bottom surface 107. Distance D2, which is the distance from the tip 113 to the exposed portion 121 ensures that the exposed portion 121 does not enter receptacle 92, but does enter receptacle 82, when the needle electrode 112 is fully inserted into receptacle 80. Conductors 135, 136, 137 (FIG. 9) are bonded to conducting needle 114, conducting film 118, and conducting film 121, respectively, at the external end 139 of needle electrode 112. Receptacles 82 and 92 have no bottom surface. Therefore, a needle that is inserted into septum 84 of receptacle 82 may pass through the metal fibers 16 in receptacle housing 86, through septum 94, through metal fibers 16 in receptacle housing 96, through septum 104, and into the metal fibers 16 of receptacle housing 106. The needle may then bottom out on the bottom surface 107 of receptacle 102. Thus, the insertion of needle electrode 112 into multi-chambered receptacle 80 permits multiple direct electrical connections between an external unit and an implanted medical device for battery charging or other electrical connection functions with a single needle penetration.
While preferred embodiments of this invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit or teaching of this invention. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the system and apparatus are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims which follow, the scope of which shall include all equivalents of the subject matter of the claims. | A connector apparatus system and method for providing a direct electrical connection to an implanted medical device for recharging batteries, reprogramming memory, or accessing data. The apparatus consists of a needle-like male connector in conjunction with an implantable female connector that is attached to the implanted medical device and contains a self-resealing elastomeric septum entry port. The female connector comprises a recepticle chamber that is densely packed with a plurality of randomly intertwining, thin, flexible, and conductive metal fibers. External battery charging equipment can be connected to the implanted medical device's internal battery with the connector apparatus system. The required circuit path for recharging can be completed by the use of two single polarity connector pairs, one single polarity connector pair in conjunction with a grounding plate, or one bipolar connector pair. For the bipolar embodiment of the connector, the male portion has two conductors seperated by a sleeve of insulating film while the female portion has two stacked cavities, each with separate sealing septums. A multi-polar embodiment of the connector can be used to interface with the implanted device for functions requiring multiple connections. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the U.S. national phase application of PCT International Application No. PCT/EP2009/006653, filed Sep. 15, 2009 which claims priority to European Patent Application No. EP 08016171.4 filed Sep. 15, 2008 the contents of such applications being incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to a method and a device to early predict the Kt/V parameter in kidney substitution treatments.
BACKGROUND OF THE INVENTION
[0003] Dialysis adequacy is the topic that has got and gets more attention when one thinks about patient outcome. In order to estimate dialysis adequacy one needs a parameter establishing a relation between dialysis dosage and patient outcome. The most accepted parameter to estimate the quantity of dialysis delivered or dosage is the Kt/V, where K is the effective clearance for urea, t is the treatment time and V is the urea distribution volume which matches the total body water.
[0004] The NCDS (National Cooperative Dialysis Study) and the HEMO study found, after analyzing a large patient group, that morbidity and mortality in end stage renal disease (ESRD) was strongly correlated with the Kt/V value or dialysis dose. Data obtained from these studies resulted in guidelines regarding hemodialysis treatments, which demand a minimum dose of Kt/V=1.2 for non-diabetic patients and 1.4 for diabetics (DOQI guidelines). It is worthy to point out that a morbidity decrease not only improves the patient well-being, but also reduces significantly the medical costs as the patient requires less care.
[0005] The need of a reliable and cost effective method to monitor the Kt/V and by extension control dialysis adequacy and morbidity, would therefore be easily understood to one of ordinary skill in the art from the description herein.
[0006] In the Kt/V calculation, the main problems are K and V estimation along with the multicompartment urea kinetics. V can be estimated by bioimpedance, anthropometric measurements or applying the urea kinetic model (UKM), all these methods have a certain degree of error. K can be estimated so far by measuring the urea blood concentration before and after the treatment or by monitoring inlet and outlet conductivity changes in the dialysate side.
[0007] Blood samples method is the reference one. After taking the blood samples and applying either UKM or Daugirdas formula a single pool Kt/V (spKt/V) is estimated, further, Daugirdas second generation formulas should be used to get an equilibrated Kt/V (eKt/V) which accounts for the urea rebound caused by the fact that urea kinetic's does not follow a single pool model but a multi-compartment one. This method has two main problems: it is not possible to know whether the treatment is adequate or not before it finishes, therefore it is not possible to perform any action to improve the situation; it is not an easy to apply method: sampling time is very important to get an accurate value, and the medical staff must send the samples to the lab, wait for the results and calculate Kt/V values with the help of a computer. These facts result on a monthly basis Kt/V measurements in best case, which means that in worst case scenario a patient might be under-dialyzed for one whole month.
[0008] Conductivity methods are based on the observation that sodium clearance is almost equal to urea clearance and that the relationship between dialysate conductivity and dialysate sodium concentration can be considered linear on the temperature range of interest. Therefore it is possible to get urea clearance by measuring the sodium diffusion transport through the membrane in the dialyzer.
[0009] It is important to introduce the concept of Dialysance, as it slightly differs from Clearance:
[0010] Clearance is defined as the ratio between transport rate and concentration multiplied by flow, and it is applicable when the diffusing substance is on the blood side but not on the dialysate, that is the case for urea.
[0011] Dialysance is defined as the ratio between transport rate and concentration gradient multiplied by flow, and it is applicable when the diffusing substance is in both dialyzer sides. When one applies conductivity methods to measure urea Clearance, one actually measures sodium Dialysance (see Depner T, Garred L. Solute transport mechanisms in dialysis. Hörl W, Koch K, Lindsay R, Ronco C, Winchester J F, editors. Replacement of renal function by dialysis, 5th ed. Kluwer academic publishers, 2004:73-91).
[0012] During conductivity based clearance measurements, a dialysate inlet conductivity different to the blood one is produced, which results in a net transfer of sodium either from blood to dialysate or from dialysate to blood due to the generated gradient. There are currently several methods which are applied in the industry:
[0013] In a first method a one-step conductivity profile is performed; in a second method a two-step conductivity profile is performed; and in a third method an integration of conductivity peaks is used. (see Polaschegg H D, Levin N W. Hemodialysis machines and monitoris. Hörl W, Koch K, Lindsay R, Ronco C, Winchester J F, editors. Replacement of renal function by dialysis, 5th ed. Kluwer academic publishers, 2004:414-418). The main advantages of this approach is that it is relatively easy to implement and cost effective as it only needs an extra conductivity/temperature sensor downstream the dialyzer. It offers Kt/V measurements during the treatment allowing the medical staff to react and perform some actions in case the treatment is not going as it should. However, conductivity based methods have also some limitations: they can induce some sodium load in the patient during the measurement; they are not useful to obtain other interesting parameters like nPCR or TRU. The maximum measurement frequency offered so far by the industry is about 20 minutes, which means that in worst case scenario the patient could be under-dialyzed for 20 minutes. And although there are some publications claiming it, so far, conductivity methods haven't been applied with enough reliability to hemofiltration or hemodiafiltration treatments.
[0014] Another method to estimate hemodialysis adequacy is by direct measurement of the waste products (urea) concentration in the effluent dialysate, this method assumes that the evolution of urea concentration over the time in the dialysate side is proportional to the one in the blood, therefore the slope of the line obtained after applying the natural logarithm to the registered concentration values over the time will be the same on both sides: dialysate side and blood side. And by definition such slope is K/V, which multiplied by the therapy time results in the Kt/V value.
[0015] There are two different methods available to measure online the concentration of waste products in effluent dialysate: Urea sensors and UV spectrophotometry.
[0016] The limitations of the urea sensors are well known. Recent works carried out by Fridolin I. et al (see I. Fridolin, M. Magnusson, L.-G. Lindberg. On-line monitoring of solutes in dialysate using absorption of ultraviolet radiation: Technique description. The International Journal of Artificial Organs. Vol. 25, no. 8, 2002, pp. 748-761) and Uhlin F. (see Uhlin F. Haemodialysis treatment monitored online by ultra violet absorbance. Linköping University Medical Dissertations n° 962. Department of Medicine and Care Division of Nursing Science & Department of Biomedical Engineering. 2006.) have shown that UV spectrophotometry is a reliable and cost affordable method to monitor waste products in effluent dialysate. Additionally, the European Patent EP1083948B1 describes a sensor coupled with the dialysate flow system of a dialysis machine, which is actually an UV spectrophotometer measuring UV absorbance of UV absorbing products in spent dialysate.
[0017] Using any of the online measuring methods it is possible to know the delivered Kt/V at any treatment time, but it is not possible to predict with enough accuracy how much Kt/V will be delivered to the patient at the end of the dialysis session. Such information would be of great value for the physician in order to adjust the treatment parameters and improve the dialysis efficiency.
[0018] The delivered Kt/V by unit of time it is not constant during the treatment because of the multi-compartment nature of the urea kinetic model. During the dialysis treatment we can speak about two clearances, one between the dialysate and the extra cellular compartment, and another between intra and extra cellular compartment, which is smaller than the first one. On the first stage of the dialysis treatment the extra cellular compartment is quickly cleared, further on, the concentration decrease of waste products in blood slows down because the dialyzer clearance is limited by the clearance between compartments, in other words the uptake of waste products by the extra cellular from the intra cellular compartment is smaller than the dialyzer blood clearing capabilities. From the mathematical point of view it can be noticed by the fact that the ratio K/V decreases, thus the Kt/V by unit of time also decreases as the dialysis goes on.
[0019] The shortcomings of the methods measuring the clearance by means of conductivity have been already described, besides it linearizes the Kt/V along the whole dialysis treatment and introduce a prediction error because of both the low measurement frequency and the approximation of V.
[0020] When measuring Kt/V by means of the data delivered by any sensor or measuring device, which is able to continuously measure any waste product on spent dialysate, the high measuring frequency and the wealth of data allow to make an accurate prediction of the final Kt/V value.
SUMMARY OF THE INVENTION
[0021] Aspects of the invention are directed to providing a reliable method and device to determine or predict the final Kt/V value.
[0022] In accordance with one aspect of the present invention, a method is disclosed for determining or predicting the adequacy parameters that will be achieved at the end of a kidney substitution treatment during said kidney substitution treatment, wherein the kidney substitution treatment is provided by a machine, which has an extracorporeal blood system pumping the patient blood at a preset blood flow rate through the blood chamber of a dialyzer, which is divided by a semi-permeable membrane into the blood chamber and a dialyzing fluid chamber and wherein the dialyzing fluid flows at a preset flow rate through the dialyzing fluid system of the machine and collects the waste products from the patient after flowing through the dialyzing fluid chamber of the dialyzer and wherein a device able to measure continuously any kidney substitution treatment related waste product to deliver together with the data provided by the kidney substitution treatment machine a adequacy parameter wherein the device is coupled with the dialyzing fluid system of the kidney substitution treatment machine and wherein the slope of a preferable linear guideline for the adequacy parameter, which end at target adequacy parameter at the end of the kidney substitution treatment, is compared to the slope of the delivered adequacy parameter and if the slope of both are equal with the next delivered adequacy parameters a linearization is performed to determine or predict the adequacy parameter at the end of the kidney substitution treatment.
[0023] In accordance with another aspect of the present invention, a device is disclosed which is a kidney substitution treatment machine, wherein the method described herein is implemented, wherein the user can set a planned adequacy parameter at the end of the kidney substitution treatment and wherein an alarm or warning system is implemented to let the user know that the planned adequacy parameter at the end of the kidney substitution treatment will not be achieved.
[0024] Further goals, advantages, features and possibilities of use of this invention arise out of the subsequent description of the embodiments of the invention. Therefore every described or depicted feature of its own or in arbitrary meaningful combination forms the subject matter of the invention even independent of its summary in the claims or its reference to other claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] It shows:
[0026] FIG. 1 Depicts a portion of a conventional dialysis machine plus a slight modification to host a sensor coupled with the dialysate circuit,
[0027] FIG. 2 Graph with the spKt/V guideline, FIG. 3 Graph with the eKt/V guideline and
[0028] FIG. 4 One of the possible graphic implementations of a warning system, which notifies the user whether or not a preset goal Kt/V will be achieved at the end of the dialysis treatment.
[0029] FIG. 5 Depicts a block diagram of a client-server functionality used to maintain and update prediction models for parameters evaluating the adequacy of a dialysis treatment.
[0030] FIG. 6 Depicts one of the possible embodiments of a self-learning software system able to adjust the Kt/V prediction to the singularities of each patient.
DETAILED DESCRIPTION OF THE INVENTION
[0031] Aspects of the invention are now described with the help of a mathematical derivation.
[0032] FIG. 1 shows a draw of the dialysate circuit of a conventional dialysis machine plus a slight modification to host a sensor coupled with the dialysate circuit. The blood from a patient is taken out into an extracorporeal circuit, it flows through the tube 32 into the blood chamber 30 of a dialyzer and returns to the patient through the tube 31 . The flow rate of the blood circuit is controlled by the blood pump 33 . The dialysis fluid is made of several concentrates and water, therefore the machine disclosed in FIG. 1 comprises a water inlet 12 , two concentrates inlets 16 and 18 and two concentrate pumps 17 and 19 . The water flow together with the concentrates flow defines the final properties of the dialysis fluid. The conduit 20 takes the dialysis fluid to the dialysate chamber 29 of the dialyzer, which is separated from the blood chamber 30 by a semi permeable membrane. The dialysis fluid it is pumped into the dialyzer by the pump 21 . A second pump 34 sucks the dialysis fluid and any ultrafiltrate removed from the blood. A bypass line 35 is arranged between the pumps 21 and 34 . Several valves 26 , 27 and 28 are arranged to control the dialysate flow. The conduit 36 leads the spent dialysate to a UV-sensor 37 measuring its light absorbance, the UV-sensor 37 is connected by an interface with the computer 14 which processes the measured data, the result of the data processing is displayed and/or printed by the device 15 , which is connected with the computer 14 by an interface. The conduit 36 leads the spent dialysate after its measurement by the UV-sensor 37 to the drain system 13 . The dotted lines 22 , 24 and 25 represent an adaptation of the disclosed apparatus for hemodiafiltration treatments. The substitution fluid comes from a substitution fluid source 11 , flows through the line 22 and is pumped in the blood lines of the patient by the pump 23 . In case of post dilution hemodiafiltration the conduit 24 leads the substitution fluid to the venous line of the extracorporeal blood system; in case of pre dilution hemodiafiltration the conduit 25 leads the substitution fluid to the arterial line of the extracorporeal blood system; and in case of pre-post dilution hemodiafiltration both conduits 24 and 25 are used. The computer 14 controls all the elements shown on the figure by means of proper interfaces, said interfaces are not drawn for the sake of simplicity. The computer 14 gathers information about other parameters of the dialysis machine, like for example blood flow, dialysate flow and/or therapy time, these parameters together with the measured data are processed, the result tunes the Kt/V measuring functionality to assess deviations.
[0033] The UV-sensor 37 can be substituted by an Urea-sensor, in this case will the urea concentration in spent dialysate measured instead of the light absorbance. The disclosed dialysis machine is provided with several other means as is conventional. These other means are not disclosed, since they are not relevant for the operation of the present invention.
1.—Kt/V Guideline
[0034] At the beginning of the treatment, both the goal or prescribed Kt/V and the treatment time are used to work out a linear Kt/V guideline, the slope of said guideline will be compared against the slope of the delivered Kt/V at any treatment time.
[0000] Any linear function follows the form:
[0000]
y=a·x+b
Where:
[0035] a is the slope of the line
[0036] b is the offset
[0000] Then it is possible to write:
[0000]
Kt/V=a·t+b
Where:
[0037] a is the slope of the line
[0038] b is the offset
[0039] Assuming that K/V must be equal to 0 at the beginning of the treatment and equal to our goal or prescribed Kt/V at the end of the treatment, the slope “a” and the offset “b” can be calculated as follows:
[0000]
0
=
a
·
0
+
b
gKt
/
V
=
a
·
t
+
b
}
⇒
a
=
gKt
/
V
t
b
=
0
}
Where
,
gKt
/
V
is
the
goal
of
Kt
/
V
t
is
the
treatment
time
in
minutes
[0000] Special Cases: spKt/V and eKt/V
[0040] Assuming that urea is distributed in a single pool volume in the body, that urea generation rate and ultrafiltration are negligible during the session and that the ratio K/V remains constant over the dialysis, the Kt/V parameter can be expressed as follows:
[0000]
Kt
V
=
-
ln
C
t
C
0
W
here
,
C
t
is
the
blood
urea
concentration
at
time
t
.
C
0
is
the
blood
urea
concentration
at
the
beginning
of
the
treatment
.
(
1
)
[0041] However, the human body has more than one compartment. Urea is generated during the treatment and the dialysis ultrafiltration rate is significant. In order to consider these factors the guidelines recommend to express the initial “raw” Kt/V value in terms of single pool Kt/V or spKt/V using the Daugirdas second generation formula:
[0000]
spKt
/
V
=
-
ln
(
C
t
C
0
-
0.008
·
T
)
+
(
4
-
3.5
·
C
t
C
0
)
·
UF
W
(
2
)
[0000] or applying equation 1 on equation 2:
[0000]
spKt
/
V
=
-
ln
(
exp
(
Kt
V
)
-
0.008
·
T
)
+
(
4
-
3.5
·
exp
(
Kt
V
)
)
·
UF
W
(
3
)
Where:
[0042] K/V is the factor resulting from the fitting procedure.
t is therapy time in minutes.
T is therapy time in hours.
UF is ultrafiltration in litters.
W is dry weight in kilograms.
[0043] Even though the spKt/V parameter is accepted as a reliable dialysis quality indicator, it has been shown that urea rebound effects lead to significant overestimations of urea removal. It is possible to account for said effects expressing the Kt/V value in terms of equilibrated Kt/V or eKt/V using the Schneditz-Daugirdas formula:
[0000]
eKt
/
V
=
spKt
/
V
-
0.6
T
·
spKt
/
V
+
0.03
(
4
)
[0000] Where T is the therapy time in hours.
spKt/V Guideline
[0044] The procedure described to build a Kt/V guideline is also applicable to build a spKt/V guideline. The previous conditions are:
At the beginning of the treatment the spKt/V is 0. At the end of the treatment the spKt/V must be the goal spKt/V.
[0047] Thus,
[0000]
0
=
a
·
0
+
b
gKt
/
V
=
a
·
t
+
b
}
⇒
a
=
gKt
/
V
t
b
=
0
}
Where
,
gKt
/
V
is
the
goal
spKt
/
V
t
is
the
treatment
time
in
minutes
[0048] Once the factors a and b are calculated the spKt/V can be worked out for every time t.
[0049] On the FIG. 2 it is possible to see a plot of the spKt/V guideline together with a line representing the delivered Kt/V.
[0000] eKt/V Guideline
[0050] The calculation of the two linear factors “a” and “b” is a bit different due to mathematical constraints on the eKt/V equation (4), meaning that the eKt/V guideline does not cross the coordinate origin but it crosses the X axe when t is about 36 minutes. The following conditions are considered in order to work out the guideline:
According to the eKt/V calculation when t is 36 minutes eKt/V is 0.03. At the end of the treatment the eKt/V must be the goal Kt/V.
Thus,
[0053]
0.03
=
a
·
36
+
b
gKt
/
V
=
a
·
t
+
b
}
⇒
a
=
gKt
/
V
t
-
(
0.03
·
t
-
36
·
gKt
/
V
t
2
-
36
·
t
)
b
=
0.03
·
t
-
36
·
gKt
/
V
t
-
36
}
Where
,
gKt
/
V
is
the
goal
eKt
/
V
t
is
the
treatment
time
in
minutes
[0054] Once the factors a and b are calculated the should Kt/V can be worked out for every time t.
[0055] According to the previous equations the eKt/V value can be negative when the time t is lower than 36, a negative Kt/V value is not possible, therefore the guideline follows the “X” axe until the eKt/V becomes positive, which is at about 36 minutes of treatment time, and then increases constantly according to the line slope, or factor a, previously calculated.
[0056] On the FIG. 3 it is possible to see a plot of the eKt/V guideline together with a line representing the delivered Kt/V.
[0000] 2.—spKt/V and/or eKt/V Prediction by Analyzing the Delivered Kt/V
[0057] As it is described above, a dialysis machine equipped with a device able to measure continuously any dialysis related waste product, can measure and display an achieved Kt/V value at every treatment time. Therefore it is possible to approximate a line with slope “a” and offset “b” with the last delivered Kt/V data at every treatment time and, by the extrapolation of said line, work out the expected or predicted Kt/V at the end of the dialysis treatment.
[0058] As long as the Kt/V delivery is not constant during the whole dialysis procedure, being higher at the beginning of the treatment and lower at the end, the slope of the last Kt/V data will be also higher at the beginning and lower at the end, on the other side the slope of the Kt/V guideline is constant during the whole treatment (see above). At every treatment time the slope of the delivered Kt/V is compared with the slope of the Kt/V guideline. If the first is equal or lower than the second, the extrapolation of the delivered Kt/V line gives a good prediction of the Kt/V value at the end of the treatment.
[0059] Additionally, it is possible to implement a warning and/or alarm system, which tells the user if an eventually preset goal Kt/V will be reached or not: if the slope of the delivered Kt/V becomes lower than the slope of the Kt/V guideline, it means that both Kt/V lines meet at certain time point. If said time point lies before the end of the planned dialysis time, the goal Kt/V will not be reached.
[0060] The mathematical derivation of the above described warning system follows:
[0061] Assuming a delivered Kt/V line with slope “a” and offset “b”, and a Kt/V guideline with slope “c” and offset “d”:
[0000]
Kt/V
delivered
=a·t+b
[0000]
Kt/V
guideline
=c·t+d
[0000] If “a<c”, then both lines meet at certain point and the following holds:
[0000]
Kt
/
V
delivered
=
a
·
t
+
b
Kt
/
V
guideline
=
c
·
t
+
d
}
⇒
a
·
t
+
b
=
c
·
t
+
d
⇔
t
=
b
-
d
c
-
a
[0062] Being t the time point where both lines meet, if said time point lies before the end of the dialysis treatment, then the goal Kt/V will not be reached.
[0063] FIG. 4 depicts one of the possible graphic implementations of the above described warning and/or alarm system, where the different Kt/V values are displayed in written and graphic form:
The Kt/V prescribed by the physician or goal Kt/V is depicted by a thin horizontal solid line. The dotted line depicts the spKt/V guideline. The thick solid line depicts the delivered Kt/V or actual Kt/V during the first 90 minutes of treatment. The actual Kt/V field displays the already delivered Kt/V at the current treatment time. The thick dashed line extrapolates the delivered Kt/V line to the end of the treatment, it gives a visual idea of the expected Kt/V at the end of the treatment if the current dialysis conditions are kept constant. The prognosis field displays the expected Kt/V at the end of the treatment if the current dialysis conditions are kept constant.
[0070] FIG. 4 , shows a situation where the prescribed Kt/V will not be reached and therefore the warning system will be enabled.
[0000] 3,—spKt/V and/or eKt/V Prediction by Using an Statistical Model
[0071] In another possible embodiment a prediction model based on the statistical analysis of patient data delivers a predicted value since the beginning of the treatment, when the slope of the delivered Kt/V line is greater than the one of the Kt/V guideline, and therefore the line extrapolation approach is not applicable.
[0072] The data required to build said prediction model is stored in a central database. The model is recalculated, respectively updated every time that new data comes. The way the central database is populated depends on the presence of an integrated network interface in the dialysis machine. If a network interface is absent, the treatment data must be manually downloaded and stored from the machine to the database. If a network interface is present, when the a treatment is over, an implemented software function sends the data to a network service connected with the database. Said data transfer triggers the model recalculation. Before starting the treatment, the dialysis machine requests the last updated model to the network service, the updated model is sent back to the dialysis machine and will be applied to the next treatment. The network service may be a LAN-service (Local Area Network), a WAN-service (Wide Area Network) or even a webservice.
[0073] It is also possible to store many models in the database. Said models may aim to different populations of dialysis patients and can, therefore, deliver better predictions. In such cases the machine transfers to the network service defined patient data. The network service serves back a model best suiting the patient being treated: for example models based on patient gender, age, ethnic origin, etc.
[0074] FIG. 5 depicts a block diagram where this functionality is disclosed. 1 the dialysis machines request to the network service the updated model. 2 the network service requests to the database the updated model and serves it back to the dialysis machines. 3 the dialysis machine sends to the network service new treatment data. 4 the network service hands the treatment data to the database which stores it; the database interacts with the calculation algorithm to recalculate the model; the new model is stored in the database, and is therefore available for further requests of the dialysis machines.
[0075] The statistical model may include any combination of the following parameters:
[0000] a. Dialysis Machine Related Parameters:
Achieved Kt/V, spKt/V, eKt/V, URR, spURR or eURR value. Alarm and/or warnings. Arterial bolus. Arterial bolus volume and flow. Arterial pressure on the machine's arterial pressure sensor. Bag weight in case of hemodiafiltration with substitution fluid in bags. Balance chamber ultrafiltration removal. Blood flow and/or blood pumps revolutions. Blood hematocrit. Blood oxygen saturation. Blood pressure at dialyzer inlet. Blood temperature. Concentrate pumps revolutions. Dialysate composition. Dialysate conductivity. Dialysate flow status of the machine: bypass or treatment. Dialysate flow and/or dialysate pumps revolutions. Dialysate temperature. Dialyzer's transmembrane pressure. Heparin bolus event and quantity of injected heparin. Heparin rate. Heparin syringe type. Ultrafiltration volume. Ultrafiltration rate. Used dialysis concentrates. UV absorbance on spent dialysate. Sequential dialysis periods: duration, ultrafiltrated volume and timestamp. Signals recorded by an UV spectrophotometer coupled with the dialysate flow system. Substitution fluid bolus in hemodiafiltration (HDF). Substitution fluid volume in HDF. Substitution fluid rate in HDF. Substitution fluid composition. Substitution pump revolutions. Therapy time. Type of HDF: pre-dilution, post-dilution or pre-post-dilution. Venous pressure on the machine's venous pressure sensor.
[0112] Any of the above listed parameters can be used with or without association with its timestamp. In case of an event, as for example an alarm, the treatment time when the event took place may be recorded and used in the prediction model. In case of a quantitative variable, the treatment time when the variable reached certain value may be recorded and used in the prediction model.
[0113] Any combination of the above listed parameters may be used on the prediction model.
[0114] Any mathematical operation using as operands any of the above listed parameters may deliver a new parameter that may be used on the prediction model.
[0000] b. Patient Related Parameters:
Access recirculation. Age. Blood pressure during the treatment. Blood urea concentration pre dialysis. Blood urea concentration post dialysis. Concomitant diseases. Clinical history data. Date of first hemodialysis. Dialysis per week. Dialyzer surface. Dialyzer type: High flux or low flux. Dry weight. Ethnic origin. Glomerular filtration rate. Hematological disorders. Height. Kidney disease. Life expectancy. Modality of kidney substitution treatment. Patient's clinical history. Psychological status of the patient. Residual diuresis. Sex. Stability of the vascular access. Time in chronic dialysis. Type of vascular access. UV absorbance at treatment begin. UV absorbance at treatment end. Weight after dialysis. Weight pre dialysis.
[0145] Any combination of the above listed parameters may be used on the prediction model.
[0146] Any mathematical operation using as operands any of the above listed parameters may deliver a new parameter that may be used on the prediction model.
[0000] The prediction model may be linear or non-linear, in our preferred embodiment we use a linear model of the following form:
[0000] y=β 1 +β 2 ·γ 1 +β 3 ·γ 2 + . . . +β n ·γ n-1 +ε
Where,
[0147] y is the actual value to be estimated.
[0148] βi, β2, . . . , βn are the empirical factors constituting the model.
[0149] γ 1 , γ 2 , . . . , γ n-1 are the variables correlating with the estimated value. In our case any of the above listed variables
[0150] ε is the residual error between the actual value and the value estimated by the β factors and γ variables.
[0151] Our model, disclosed in the following equation, use some of the above listed parameters to predict the UV-light absorbance at the end of the treatment.
[0000]
A
(
T
)
=
β
1
+
β
2
·
f
(
A
t
1
)
+
β
3
·
f
(
UF
)
+
β
4
·
f
(
G
)
+
β
5
·
f
(
T
)
+
β
6
·
f
(
BF
)
+
β
7
·
f
(
t
1
)
+
β
8
·
f
(
A
t
1
,
t
1
)
+
β
9
·
f
(
T
,
G
)
+
β
10
·
f
(
UF
,
T
)
+
β
11
·
f
(
BF
,
G
)
+
β
12
·
f
(
UF
,
BF
)
+
β
13
·
f
(
A
t
1
,
T
)
+
β
14
·
f
(
A
t
1
,
G
)
+
ɛ
Where,
[0152] A(T) is the UV-absorbance value at the end of the treatment.
[0153] Au is the first UV-absorbance measurement.
[0154] UF is the programmed ultrafiltration.
[0155] G is the patient weight before starting the treatment.
[0156] T is the planned treatment time.
[0157] BF is the programmed blood flow.
[0158] ti is the timestamp of the first absorbance measurement.
[0159] ε is the residual error between the actual value A(T) and the estimated final absorbance value.
[0000] Knowing the initial and the final predicted absorbance values allows to calculate a predicted Kt/V value by any of the following means:
Using the initial and final absorbance values by means of the following equation:
[0000]
Kt
V
=
-
ln
(
A
t
A
0
)
(
5
)
Given the initial and final absorbance values, a decaying exponential curve matching the urea kinetics can be generated. Different fitting procedures can be applied to the exponential curve to obtain the Kt/V value; like for example a logarithmic linearization of the curve plus a linear fit; a non-linear fit algorithm like as for example the Levenberg-Marquardt algorithm; etc. Any of the procedures can be either applied to the curve as a whole; or, to increase the accuracy, the curve may be split in subsets, on which the fitting procedures are applied, the final Kt/V will be in this case the addition of each of the subset based Kt/Vs.
[0162] Instead of estimating the final absorbance value, it is also possible to directly predict the final Kt/V value, or the final raw signal coming from the UV-sensor, which can be used to calculate the final absorbance and by extension the final Kt/V value.
[0000] 4.—spKt/V and/or eKt/V Prediction by an Statistical Model in Combination with the Analysis of the Delivered Kt/V.
[0163] It is also possible to combine the statistical model described above with an analysis of the already delivered Kt/V. This approach enhances the accuracy of the prediction by using the actual treatment data to tune the initial statistical estimation.
[0164] The combination algorithm may be based on any of the in section 3 listed variables. In our preferred embodiment we base it on achieved treatment time (equation 6). The combination algorithm can work at any level: raw sensor signal, absorbance or Kt/V. In our preferred embodiment the initial estimation is weighted by a factor calculated from the analysis of the raw sensor signal. The effect of the weighting factor depends on the treatment time and increases as the treatment advances. A detailed description of the process follows:
[0165] A.—Estimation of the final absorbance value by using the statistical model described in section 3 . The estimated final absorbance is expressed in terms of raw sensor signal.
[0166] B.—During the dialysis treatment, a constant monitoring of the raw sensor signal delivers an estimation, exclusively based on actual treatment data, of the expected signal at the end of the treatment.
[0167] C—Both estimations, statistical and treatment based, are combined in a final prediction. The weight that each of the components has in this final prediction depends on the treatment time. At time 0 , the final prediction equals the statistical estimation; while at the end of the treatment the contribution of the statistical component is zero. The following equation describes how both components are combined:
[0000]
Signal
Final
=
(
1
-
(
t
T
)
2
)
·
Signal
Stats
+
(
t
T
)
2
·
Signal
Treatment
(
6
)
[0000] Where t is the current treatment time and T is the total treatment time.
[0168] D.—The final prediction is expressed in terms of absorbance, and the estimated final Kt/V can be obtained, as described in the previous section, by using the initial and end absorbance values (equation 5) or by fitting a decaying exponential curve.
5.—Individualized Improvement of the Kt/V Prediction by Means of Intelligent Systems
[0169] Many dialysis machines in the market offer the possibility of saving patient related parameters in a suitable media: diskette, patient card, etc. The statistical model described above can be stored on the patient card, and may be adjusted by an intelligent algorithm to better suit a given patient. The intelligent algorithm can be based on traditional feedback logic, fuzzy logic or neural networks.
[0170] Our preferred embodiment consists on a pre-existing statistical model like the one described in the previous sections. At the beginning of the therapy, the machine looks for a patient adjusted prediction model in the patient card to estimate the final absorbance value; if said adjusted model is not available the pre-existing or default model will be used. The initial estimation is then compared with the actual value achieved at the end of the dialysis. If no abnormal situations have been recorded during the treatment, like for example dialyzer clotting, access recirculation, etc; and the difference between the estimated and achieved values exceeds a certain threshold; the following actions are triggered:
[0171] A.—An accumulative occurrence parameter assessing the difference between the estimated and the achieved values during the performed therapies is calculated.
[0172] B.—An intelligent algorithm either adjusts the default prediction model or tunes the patient adjusted model.
[0173] C—The new model with updated empirical factors, namely β 1 , β 2 , . . . , β 14 , is stored back in the patient card and will be available by the next therapy.
[0174] The intelligent algorithm is a neural network (NN) with supervised training through backpropagation. The NN inputs are: the variables included in the default statistical model and the accumulative occurrence parameter. The model variables are weighted within the NN with the β factors. During the backpropagation the difference between the estimated and achieved values is minimized by adjusting the β factors. This adjustment is modulated by the occurrence factor. FIG. 6 discloses one of the possible solutions for the described neural network.
6.—Feed-Back Control of the Treatment Parameters Based on the Kt/V Prediction
[0175] As long as a reliable prediction of the Kt/V at the end of the dialysis is available, it is possible to compare at every treatment time the predicted Kt/V with the target Kt/V. A feed-back control can be implemented. Said control would use as reference or desired value the target Kt/V, as control variable the predicted Kt/V and as actuating variable any machine parameter that can have an influence on the final Kt/V. With such a system each treatment would be adjusted to the dialysis dosage that must be delivered to each patient according to the medical prescription.
[0176] The main parameters affecting the Kt/V are the blood flow, the dialysate flow, the substitution fluid flow in case of hemodiafiltration and the therapy time, therefore any variable or combination of variables having an effect on the listed parameters are suitable to become actuating variables. Among them it is important to point out the revolutions of the blood, dialysate and substitution pumps, and the software control of the treatment length based on the machine timer.
[0177] Controlling the treatment parameters to achieve the target Kt/V has the following clear advantages:
Avoids having underdialyzed patients. Optimizes the consumption of dialysate and therefore concentrates. Optimizes the time a patient is connected to the machine. | A method for determining or predicting the adequacy parameters that will be achieved at the end of a kidney substitution treatment during said kidney substitution treatment wherein the kidney substitution treatment is provided by a machine, which has an extracorporeal blood system pumping the patient blood through the blood chamber of a dialyzer, wherein the dialyzing fluid collects the waste products from the patient after flowing through the dialyzing fluid chamber of the dialyzer and wherein a device able to measure a adequacy parameter is coupled with the kidney substitution treatment machine and wherein the slope of a preferable linear guideline for the adequacy parameter is compared to the slope of the delivered adequacy parameter and if the slope of both are equal a linearization is performed to determine or predict the adequacy parameter at the end of the kidney substitution treatment. | 0 |
BACKGROUND--FIELD OF INVENTION
This invention relates to the use of force responsive sensors and circuitry to detect the level of material within a storage bin, hopper, tank or the like and specifically to the control of an electric motor in response to the level of the material.
BACKGROUND--DESCRIPTION OF PRIOR ART
One of the management problems facing livestock and poultry producers today is that of the cost and reliability of manual labor. Delivering feed to livestock or poultry at the proper time and in the proper amount has been a major effort of farm labor. In the past this was done by carrying the feed to the animals in a bucket and dumping it into a feed trough. More recently this has been done by motor driven conveyors or augers. In the poultry industry, the feed is generally transferred from a large storage bin outside the poultry house to smaller transfer bins located within the house. Each of these inside transfer bins are then the source for the feed to the feeding troughs or rings that the poultry has access to. It is important to maintain a minimum level of feed in these transfer bins but just as important to never over flow these bins.
One approach at maintaining the feed within preset levels in the bins is the use of a manually operated switch that controls the motor to refill the bin. The obvious disadvantage of this method is the requirement for a person to do the switching as they observe the level within the bin.
A paddle-type switch that is physically moved by the feed as it rises in the bin has been tried in some poultry houses. A disadvantage of this switch is its high failure rate when subjected to the harsh environment of a poultry house. These mechanical switches are not reliable and tend to hang up either open or closed after a short time in the poultry house environment. Another disadvantage is that the paddle switch allows the electric motor to "short cycle". That is, when the feed level drops only slightly, the switch closes and turns the motor on to start refilling. After only a short time, enough feed has entered the bin to depress the switch and turn the motor off. This constant "short cycling" shortens the life of the electric motor and replacement of these expensive motors requires considerable manpower and thus is a costly operation.
An attempt at solving these problems is disclosed in U.S. Pat. No. 5,051,671, issued to Crider et al, on Sep. 24, 1991. This patent addressed the environmental problem by doing away with the mechanical switch and going to a sealed capacitance type sensor. The attempt to eliminate the short-cycle problem by adding a time delay from bin full to motor turn-on for refill, did not solve the problem but only increased the time the motor would run and the time it would be off and did not correlate these times to the actual rate of the drop in the feed level within the storage bin.
Another disadvantage of this prior-art teaching is the requirement for mechanical power relays to switch the AC power to the electric motor. These relays are expensive and notoriously unreliable and require a relatively large control current to achieve activation. Because these relays can be commanded to make or break at any random time during a cycle of AC power, they can create large electric arcs if commanded to open at or near a maximum of the AC current cycle or if commanded to make at or near the peak of the AC voltage cycle. These arcs cause premature failures of these relays that can hold the motor on when not desired and cause overfilling or hold the motor off when not desired and cause a bin to run dry.
Another disadvantage of this prior art teaching is the requirement for a special and therefore expensive transformer to provide the power necessary for the control circuitry.
Yet another disadvantage is the fact that the relay switch over from one primary of the transformer to the other is not instantaneous and can cause transients and drop outs within the apparatus that can cause failures.
A further disadvantage of this prior art disclosure is the limitation of not being capable of operating two of the units in series to control a single electric motor. It is sometimes desireable to sense the material level in two bins that are filled by the action of a common electric motor which should come on only when both bin sensors are in a refill required condition and turn off when ever either bin is full. This prior art disclosure does not allow for this mode of operation.
OBJECTS AND ADVANTAGES
It is the main object of this invention to provide an apparatus that senses the level of a material within a storage bin or hopper and to control the operation of an electric motor to maintain the material between a preset full level and a preset refill required level. It is an advantage to have preset full and refill levels so as to eliminate the motor short-cycles thus reducing motor wear, lowering power useage, and to allow the system to automatically and continuously adapt to the demand for the material, always maintaining sufficient material within the storage bin or hopper.
It is yet another object of this invention to provide an apparatus that may be operated with two units in series so that control of the electric motor will cause refilling when both bins refill sensors are in a refill required condition and cause the motor to turn off whenever either bin is full.
Another object of this invention is to provide an inexpensive, technically sound, reliable, lower power, and commercially attractive apparatus using state-of-the-art solid-state electronics. A disadvantage of the prior art disclosure is the requirement for a high-power, high current mechanical relay. These expensive relays are subject to arcing across the contacts especially with inductive loads such as motors that can cause failures and limits the usefull life of the unit.
An advantage of my invention is a completely solid-state design with the inherent reliability and long life provided by state-of-the-art solid-state electronics.
Another advantage of this invention is the use of Force-Sensing Resistors as level point sensors. These touch-responsive devices are the result of the recent discovery of polymeric piezoelectric films. The Force-Sensing Resistor is made up of two polymer films, one contains a conductive pattern of electrodes and the other contains a semiconductive polymer deposite. These two films are laminated together with a combination adhesive/spacer material with conductive leads brought to one edge. The entire Force-Sensitive Resistor is less than one inch square and less than 0.050 inches thick. The resistance of the sensor as measured at the conductive pads is greater than one megohn with no pressure on the surface of the device and less than 20 k with a force of only 0.45 psi applied to the surface of the device. The Force-Sensitive Resistor is inherently protected against force overloads, exhibits no corrosion, pitting, or electrical bouce, is immune from contaminant problems such as moisture and dust, has a minimum rated life of 10,000,000 cycles, and is insensitive to vibration and acoustic pickup.
As can be readily seen from the above discussion, these Force-Sensitive Resistors can easily and positively sense the presence or absence of a material such as feed, grains, sand, and even water.
These characters of the Force-Sensitive Resistor as used for point level sensors give the apparatus of this invention another advantage over all prior-art devices. These devices are P/N 304B and are manufactured by Interlink Electronics in Carpinteria, Calif.
Another advantage of this invention is the use of a solid-state triac switch to control the power to the motor and the use of a zero-crossing optical coupler to control the state of conduction of the triac. This zero-crossing optical coupler insures that the triac and thus the AC power to the motor is always switched to on only when the AC input voltage is at a minimum. This cannot be done with a mechanical relay as used in the prior-art disclosures. Since the triac will only turn off when the current through it goes to zero, the disadvantage of a mechanical relay are adverted and we also have the added advantages of lower power necessary to drive the triac than the power relay and at a lower cost.
DRAWING FIGURES
FIG. 1 is a schematic of the triac switch and the power supply circuit illustrating how this part of the invention is configured and how the apparatus interfaces with the AC power source and the motor.
FIG. 2 is a schematic of the logic and control circuit illustrating how this part of the invention is configured and how the apparatus interfaces with the Force-Sensitive Resistor sensors.
FIG. 3 is a block diagram of the invention and how it is connected into a feed bin storage system.
DESCRIPTION
A typical embodiment of the electronics of the present invention that interface with the AC power source and the motor to generate the DC voltage for operating the control and logic circuits is illustrated in FIG. 1.
Referring to the drawing, it may be seen that the power supply circuit 10 consists primarily of a triac switch 11, a current sensing transformer 12, two bridge rectifiers 13 & 14, and a voltage regulator 15. With the motor 100 not running and the triac switch 11 not conducting, the AC Power Source 200 is routed through wire 201 to motor 100, through wire 16 to resistor 17 and capacitor 19 in series, to the bridge rectifier 14, and then through wire 202 back to the AC Power Source 200. Resistor 16 and capacitor 17 are in the circuit to limit the AC Power Source 200 voltage, typically 230 VAC or 115 VAC, into the bridge rectifier 14. Bridge rectifier 14 produces a positive DC voltage at junction 19 which passes through blocking diode 20 to the input of the voltage regulator 15. The output of the voltage regulator 15 is a positive DC voltage for powering the logic and control circuits 50 when the motor 100 is not running.
With the motor 100 running and the triac switch 11 closed or on, the AC Power Source 200 is routed through wire 201 to motor 100, through wire 21 to the primary 22 of current monitor transformer 12, to the triac switch 11, through wire 24 to wire 202 and back to the AC Power Source 200. Transformer 12 is a current monitor or sensing type. Current monitor transformers are single secondary winding devices that surround the conductor under test and use it as a primary to give a voltage output proportional to the current being monitored. The primary 22 of the current monitor transformer 12 consists of very few turns of a 16 AWG or larger wire. The large currents required to run the motor 100 pass through these few primary 22 turns and generate a voltage across the secondary 23 of the transformer 12. The voltage across the secondary 23 is rectified by bridge 13 which gives a positive DC voltage on wire 25 which passes through blocking diode 26 to the input of the voltage regulator 15. The output of the voltage regulator 15 is the same positive DC voltage as was derived above for the motor not running but now is produced when the motor 100 is running.
Since the logic and control circuits 50 require less than 10 ma of current, the components of the power circuits 10 are all small, inexpensive, low voltage, low power electronics.
A typical embodiment of the electronics of the present invention that forms the logic and control circuits and thus the operational control of the motor is illustrated in FIG. 2.
Bin full sensor 52 is a Force-Sensitive Resistor that is placed in the bin at the point chosen as the full point 102. When no force is applied to the sensor 52, that is, the feed is not touching the sensor 52, the resistance is greater than one megohm. Resistor 52 is a 100 k value and is in series with the one megohm resistance of sensor 52 to a common ground 56. Under the conditions with no force on sensor 52, the voltage at one input 55 of a logic NOR 60 is at a positive high or a logic "1" while the other input 57 is held at common ground 56 or a logic "0". The output 58 of logic NOR 60 is therefore a logic `0`.
When the material 104 in the Bin 101 rises to the preselected full position 102, it applies a force on sensor 52 causing the resistance of sensor 52 to drop to less than 20K. Resistor 53 is now in series with a sensor 52 resistance of less than 20K which lowers the voltage at input 55 of logic NOR 60 to a logic "0". With a logic "0" on each input 55 and 57, the output 58 of logic NOR 60 goes to a logic "1" or to the voltage of the positive supply.
The output 58 of logic NOR 60 is applied as an input to the reset input 91 of a Type D Flip-Flip 90. With a logic "1" to the reset 91, the output 92 of the Flip-Flop 90 will be a logic "0". The output 92 of the Flip-Flop 90 is tied directly to the gate 93 of an N-channel enhancement mode MOSFET 94. With a logic "0" or near common ground 56 on the gate 93, MOSFET 94 will be in an off or non-conducting state. With MOSFET 94 non-conducting there is not current through the light-emitting diode 95 of optical coupler 97 and thus the output 96 of optical coupler 97 is off. The output 96 of the optical coupler 97 is the drive power for the gate 98 of triac 11. With no gate 98 drive power, triac 11 is off and therefore Motor 100 is not running.
When the material 104 in the Bin 101 drops away from sensor 52, the resistance of the sensor 52 returns to its high resistance state of over one megohm. This rise in resistance causes a change of state of logic NOR 60 output 58 which returns to a logic "0" or a low voltage and removes the reset 91 from the Flip-Flop 90. However, Flip-Flop 90 will not change its output 92 state until it receives a set command or a logic "1" at input 99. This will not occur until the material 104 drops below the present refill line 103 and removes the force on sensor 51.
Whenever the material 104 is above the refill line 103 in Bin 101, sensor 51 has the force of the material 104 on it and thus is in it's low resistance condition which is less than 20K that is in series with a 100K resistor 54 to the common ground 56. Under these conditions Logic NOR 61 has both inputs at logic "0" or a low voltage and the output 62 will be a logic "1" or a high. Logic NOR 61 output 62 is tied directly to the reset 71 of another Type D Flip-Flop 70. With a logic "1" on the reset 71, the output 73 of the Flip-Flop 70 will be held at a logic "0".
When the material 104 drops below the refill line 103 in Bin 101, the force on sensor 51 is removed and the resistance of sensor 51 rises, the voltage at the input 66 to logic NOR 61 changes from a logic "0" to a logic "1" and causes the output 62 of logic NOR 61 and the reset input 71 of Flip-Flop 709 to change from a logic "1" to a logic "0". Logic NOR 63 is wired as a logic inverter and has its input as the output 62 of logic NOR 61. Therefore when the material 104 in Bin 101 drops below the refill line 103, the output 64 of inverter 63 changes from a logic "0" to a logic "1". This positive going voltage is coupled through capacitor 65 to the set input 72 of Flip-Flop 70. Capacitor 65 together with resistor 67 differentiate the output 64 of inverter 63 so the set input 72 of Flip-Flop 70 is a positive voltage spike or pulse that returns the set input 72 to near zero volts is less than a millisecond. However, once Flip-Flop 70 receives a set input 72 command, the output 73 goes high or to a logic "1" and remains in this state until a reset 71 command is received by Flip-Flop 70.
The positive going output 73 of Flip-Flop 70 is coupled through capacitor 74 to the set input 99 of Flip-Flop 90. Capacitor 74 together with resistor 75 differentiate the output 73 of Flip-Flop 70 so the set input 99 of Flip-Flop 90 is a positive voltage spike or pulse that returns the voltage at set input 99 to zero volts is less than 1 millisecond. However, once the Flip-Flop 90 receives a set input 99 command, the output 92 goes high or to a logic "1" and remains in this state until a reset 91 command is received.
When the output 92 of Flip-Flop 90 goes to a logic "1" or to a high voltage state, the gate 93 of MOSFET 94 goes high and MOSFET 94 will conduct. With MOSFET 94 conducting, current flows through the diode 95 of the optical coupler 97 and turns on the output section 96 of the optical coupler 97 which in turn applies power to the gate 98 of triac 11 and allows AC current to flow through the triac 11 and turns on the motor 100. Since the optical coupler 97 is a zero crossing type, the output 96 will actually turn on at the next zero crossing of the AC voltage applied and not at the instant the command is received.
When motor 100 comes on it will refill Bin 101 with material 104. When triac 11 turns on and motor 100 starts to run, the voltage across the triac 11 drops from the voltage of the AC Power Source 200, typically 240 VAC, to less than 2 VAC which is not sufficient to supply the necessary DC voltage to operate the Voltage Regulator 15. However, at the same time as the voltage across the triac 11 is decreasing, the voltage across the secondary 23 of current monitor transformer 12 is increasing due to the increasing current through triac 11 and motor 100 and therefore provides continuous DC voltage to the Voltage Regulator 15 through diode 26. When the level of the material 104 increases above the refill line 103 and thus covers sensor 51 once again, the resistance of sensor 51 decreases to less than 20K. This in turn causes the output 62 of logic NOR 61 to go from a logic "0" to a logic "1", the output 64 of inverter 63 to go from a logic "1" to a logic "0", the reset input 71 of Flip-Flop 70 to go to a logic "1" and the output 73 of Flip-Flop 70 to go to a logic "0". The output 92 of Flip-Flop 90 and thus the state of MOSFET 94 does not change and the motor 100 continues to run.
When the material 104 in Bin 101 reaches the full line 102 and sensor 52, it will apply force to the sensor 52 and cause its resistance to drop to less than 20K which sets into motion the events as previously described which results in the motor 100 being turned off.
The invention I have described herein operates without the requirement of an outside source of electricity as the logic and control components 50 receive power from a uniquely configured power supply 10 which allows this apparatus to easily replace an existing motor control switch system and provide the advantages of an accurate, reliable, solid-state, and yet inexpensive unit.
From the foregoing it may readily be seen that I have invented a reliable, efficient and yet inexpensive means to control and maintain the level of a material within a bin, hopper, or the like. The apparatus described herein will work equally well with materials such as feeds, grains and sand as well as with liquids.
SUMMARY RAMIFICATIONS AND SCOPE
Although the description above contains many specifications, these should not be construed as limiting the scope of the invention but merely illustrating the presently preferred embodiment of this invention. For example, the logic NOR's used in the preferred embodiment have been implemented as an MC14001 integrated circuit. This could take on other forms such as an LM339 comparator. The Type D Flip-Flop used in the preferred embodiment was implemented as a dual integrated circuit MC14013. This could be implemented in other forms including a combination of discrete bipolar transistors. The MOSFET used as a switch could easily be implemented as a bipolar transistor. It is understood that this invention may be modified in many ways within the scope of the appended claims. In particular, it is to be understood that this invention is not limited to the specific embodiment, wire configuration, electronic circuitry, logic configuration, number of sensors, or to the numerical values employed in describing the invention. Furthermore, many other types of components may be employed in practicing the invention in place of those which have been specifically described.
LEVEL SENSOR AND CONTROL APPARATUS
This list is only for convenience in referring to the drawings. It is not intended to be a part of the patent application.
REFERENCE NUMERALS USED IN THE DRAWINGS
10 Power Supply Circuit
11 Triac
12 Current Monitor Transformer
13 Bridge Rectifier
14 Bridge Rectifier
15 Voltage Regulator
16 Connecting wire
17 Resistor
18 Capacitor
19 Bridge Rectifier Positive Output
20 Diode
21 Connecting wire
22 Primary of transformer
23 Secondary of transformer
24 Connecting wire
25 Connecting wire (Bridge Rectifier Positive Output)
26 Diode
50 Logic and Control Circuit
51 Refill Sensor
52 Full Sensor
53 Resistor
54 Resistor
55 NOR Input (60)
56 Common Ground for Logic and Control Circuitry
57 NOR Input (60)
58 NOR Output (60)
60 Logic NOR
61 Logic NOR
62 NOR Output (61)
63 Logic NOR
64 NOR Output (63)
65 Capacitor
66 Resistor
70 Type D Flip-Flop
71 Reset Input (70)
72 Set Input (70)
73 Flip-Flop Output (70)
74 Capacitor
75 Resistor
90 Type D Flip-Flop
91 Reset Input (90)
92 Flip-Flop Output (90)
93 MOSFET Gate (94)
94 MOSFET
95 Optical Coupler LED (97)
96 Optical Coupler Output (97)
97 Optical Coupler
98 Triac Gate
99 Set Input (90)
100 Motor
101 Bin or Hopper
102 Full Level (101)
103 Refill Level (101)
104 material in Bin (101)
200 AC Power Source
201 Connecting Wire
202 Connecting Wire | Force responsive sensors and circuitry which detect the present and absence of a meterial within a storage bin or hopper and activates a motor to maintain the level of the material within preset limits. The sealed sensors are state-of-the-art force sensing resistive types and the circuitry is all solid-state with no relays or other mechanical devices used. The ON/OFF condition of the motor is controlled by a triac switch whose gate is optically isolated from the control circuitry with the use of a zero-crossing turn on triac optical coupler. The low voltage and low power required to operate the logic and control circuitry is derived from a pair of bridge rectifiers that receive their AC inputs from the voltage across the triac when it is not conducting and from the secondary of a current monitor transformer when the triac is conducting. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a flash memory storage system, and more particularly, to a flash memory storage system capable of facilitating access efficiency.
2. Description of the Related Art
Flash Memory, a non-volatile memory, keeps the previously stored written data upon shutdown. In contrast to other storage media, e.g. hard disk, soft disk, magnetic tape and so on, the flash memory has advantages of small volume, light weight, vibration-proof, low power consumption, and no mechanical movement delay in data access, therefore, the flash memory are for wide use as storage media in consumer electronic devices, embedded systems, or portable computers.
There are two kinds of flash memory: one is an NOR flash memory and the other is an NAND flash memory. An NOR flash memory is characteristically of low driving voltage, fast access speed, high stability, and are widely applied in portable electrical devices and communication devices, such as Personal Computers (PC), mobile phones, personal digital assistances (PDA), and set-top boxes (STB). An NAND flash memory is specifically designed as data storage media, for example, a Secure Digital (SD) memory card, a Compact Flash (CF) card, a memory Stick (MS) card. Upon writing, erasing and reading, charges move across a floating gate relying on charge coupling which determines a threshold voltage of a transistor under the floating gate. In other words, in response to an injection of electrons into the floating gate, the logical status of the floating gate turns from 1 to 0; on the contrary, in response to move electrons away from the floating gate, the logical status of the floating gate turns from 0 to 1.
The NAND flash memory contains a plurality of blocks, each block having a plurality of pages and each page dividing into a data area and a spare area. The data area which may have 512 bytes is used for storing data. The spare area is used for storing error correction code (ECC). However, the flash memory fails to change data update-in-place, that is, prior to writing data into a non-blank page, erasing a block including the non-blank page is required. In general, erasing a block take as much time as 10-20 times greater as writing into a page. If a size of written data is over an assigned block, the filled pages in the assigned block have to be removed to other blocks, and then erasing the assigned block is performed.
Furthermore, flash memory block may fail to access when in excess of one million times of erasures before the block is considered to be worn out. This is because the number of erasure times for a block is close to one million, charge within the floating gate may be insufficient due to current leakage of realized capacitor, thereby resulting in data loss of the flash memory cell, and even failure to access the flash memory. In other words, if erased over a limited times, a block may be unable to be accessed.
There are two kinds of NAND flash memory: one is a multi-level cell (MLC) NAND flash memory and the other is a single-level cell (SLC) flash memory. A cell of the MLC NAND flash memory includes a floating gate for storing various charge levels indicative of binary value 00, 01, 10, and 11. Therefore, each MLC NAND flash memory cell can store four values one time. Conversely, the SLC NAND flash memory cell has thinner oxide film between the floating gate and the source. During writing process, voltage is applied onto the floating gate, thereby the stored charge being driven to flow out through the source. Each SLC NAND flash memory cell may store only one-bit data, as is less than MLC NAND flash memory cell. In addition, a speed of an access to the MLC NAND flash memory is faster than that to the SLC NAND flash memory cell. Nevertheless, a number of access to the SLC NAND flash memory may be one hundred thousand times, while the MLC NAND flash memory can be accessed by ten thousand times. That is, a life of the MLC NAND flash memory is shorter than that of SLC NAND flash memory. Moreover, the MLC NAND flash memory consumes more power than the SLC NAND flash memory by about 15%.
Please refer to FIG. 1 and FIG. 2 . FIG. 1 shows a diagram of a storage memory device using SLC NAND flash memory, and FIG. 2 shows a diagram of a storage memory device using MLC NAND flash memory. At present, the storage devices 70 using the MLC NAND flash memory are almost low access speed. The storage device 70 accesses multiple MLC NAND flash memory areas 74 by means of the controller 72 . Conversely, the storage devices 80 using the SLC NAND flash memory are almost used in high performance memory card. The storage device 80 accesses multiple SLC NAND flash memory areas 84 by means of the controller 82 . Because the demands for the flash memory storage device are different, it is necessary to develop a flash memory device capable of determining to store a file into the MLC NAND flash memory or a SLC NAND flash memory to meet the user desires.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a flash memory storage system capable of facilitating access efficiency, by determining to store a file into the MLC NAND flash memory or a SLC NAND flash memory based on the file's data characteristics.
Briefly summarized, the flash memory storage device provides a Multi-level cell(MLC) flash memory for storing data, a single-level cell (SLC) flash memory for storing data, and a control unit for determining to store a file into the MLC NAND flash memory or a SLC NAND flash memory based on the file's data characteristics.
In one aspect of the present invention, if the size of the file exceeds a predetermined value, the control unit controls the file to store in the MLC NAND flash memory, otherwise, the control unit controls the file to store in the SLC NAND flash memory.
In another aspect of the present invention, if the file is a video file or an audio file, the control unit controls the file to store in the MLC NAND flash memory. If the file is a configuration file, the control unit controls the file to store in the SLC NAND flash memory.
The present invention will be described with reference to the accompanying drawings, which show exemplary embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a diagram of a storage memory device using SLC NAND flash memory.
FIG. 2 shows a diagram of a storage memory device using MLC NAND flash memory.
FIG. 3 shows a block diagram of the storage system according to a preferred embodiment of the present invention.
FIG. 4 depicts a cell structure of the MLC NAND flash memory.
FIG. 5 illustrates a cell structure of the SLC NAND flash memory.
DETAILED DESCRIPTION OF THE INVENTION
Please refer to FIG. 3 which shows a block diagram of the storage system 10 according to a preferred embodiment of the present invention. The storage system 10 comprises a host 20 and a flash memory storage device 50 . The host 20 may be a desktop computer, a notebook computer, an industrial computer or a recordable DVD player. The host 20 comprises a processing unit 22 for communicating between an operating system and bus drivers. The flash memory storage device 50 comprises a control unit 52 , a MLC NAND flash memory 54 , and a SLC NAND flash memory 56 .
Please refer to FIG. 4 depicting a cell structure of the MLC NAND flash memory, and FIG. 5 illustrating a cell structure of the SLC NAND flash memory. The cell of the MLC NAND flash memory 54 comprises a floating gate 542 , a source 544 , a drain 546 , a gate 548 , and an oxide film 545 . Upon charge flows from the source 544 to the cell of MLC NAND flash memory 54 , the floating gate 542 may store four states indicative of four digital values 00, 01, 10, and 11. The cell of the SLC NAND flash memory 56 comprises a floating gate 562 , a source 564 , a drain 566 , a gate 568 , and an oxide film 555 . The oxide film 565 sandwiched between the floating gate 562 and the source 564 is thinner, so that, during writing process, voltage is applied onto the floating gate 562 , thereby the stored charge being driven to flow out through the source 564 . In doing so, each SLC NAND flash memory cell may store only one-bit data.
When the flash memory storage device 50 is coupled to the host 20 , the user can input command to access the flash memory storage device 50 by means of a graphic user interface 24 . On receiving the user's command, the processing unit 22 sends a request to access data stored in the flash memory storage device 50 . The control unit 52 will verify the location and data characteristics of the access file in response to the request. In the first embodiment, one of the file's data characteristics indicates a size of the file. If the size of the file exceeds a predetermined value, the control unit 52 sets the channel 62 to link to the MLC NAND flash memory 54 , and then stores the file in the MLC NAND flash memory 54 . Otherwise, the control unit 52 sets the channel 64 to link to the SLC NAND flash memory 56 , and then stores the file in the SLC NAND flash memory 56 . In a second embodiment, if the size of the file exceeds a predetermined value, the control unit 52 sets the channel 64 to link to the SLC NAND flash memory 56 , and then stores the file in the SLC NAND flash memory 56 . Otherwise, the control unit 52 sets the channel 62 to link to the MLC NAND flash memory 54 , and then stores the file in the MLC NAND flash memory 54 .
In the third embodiment, another one of the file's data characteristics indicates a format of the file. If the file is a video file or an audio file using such a format as JEPG, MPEG, AVI, RM etc., the control unit 52 sets the channel 62 to link to the MLC NAND flash memory 54 , and then stores the file in the MLC NAND flash memory 54 . If the file is a configuration file which may be a key file, the control unit 52 sets the channel 64 to link to the SLC NAND flash memory 56 , and then stores the file in the SLC NAND flash memory 56 . In a fourth embodiment, if the file is a video file or an audio file using a format such as JEPG, MPEG, AVI, RM etc., the control unit 52 sets the channel 64 to link to the SLC NAND flash memory 56 , and then stores the file in the SLC NAND flash memory 56 . If the file is a configuration file which may be a key file, the control unit 52 sets the channel 62 to link to the MLC NAND flash memory 54 , and then stores the file in the MLC NAND flash memory 54 .
In contrast to prior art, the flash memory storage device of the present invention provides both the MLC NAND flash memory and the SLC NAND flash memory. The control unit can determine to store a file into the MLC NAND flash memory or the SLC NAND flash memory based on the file's data characteristics. In this way, the present invention flash memory storage device can boost efficiency in accessing flash memory.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | A flash memory storage device for boosting efficiency in accessing flash memory is disclosed. The flash memory storage device provides a Multi-level cell (MLC) flash memory for storing data, a single-level cell (SLC) flash memory for storing data, and a control unit for determining whether to store a file into the MLC NAND flash memory or a SLC NAND flash memory based on the file's data characteristics. | 6 |
RELATED APPLICATIONS
[0001] This patent application makes reference to, claims priority to and claims benefit from U.S. Provisional Patent Application Ser. No. 60/617,457, entitled “System and Method for Performing Inverse Telecine Deinterlacing of Video by Bypassing Data Present in Vertical Blanking Intervals” filed on Oct. 8, 2004, the complete subject matter of which is hereby incorporated herein by reference, in its entirety.
[0002] This application makes reference to:
U.S. Provisional Patent Application Ser. No. 60/540,717, filed on Jan. 30, 2004; U.S. application Ser. No. 10/945,769 filed Sep. 21, 2004; U.S. application Ser. No. 10/875,422 filed Jun. 24, 2004; U.S. application Ser. No. 10/945,619 filed Sep. 21, 2004; U.S. application Ser. No. 10/945,587 filed Sep. 21, 2004; U.S. application Ser. No. 10/871,758 filed Jun. 17, 2004; U.S. application Ser. No. 10/945,817 filed Sep. 21, 2004; U.S. application Ser. No. 10/945,729 filed Sep. 21, 2004; U.S. application Ser. No. 10/945,828 filed Sep. 21, 2004; U.S. application Ser. No. 10/946,152 filed Sep. 21, 2004; U.S. application Ser. No. 10/871,649 filed Jun. 17, 2004; U.S. application Ser. No. 10/946,153 filed Sep. 21, 2004; U.S. application Ser. No. 10/945,645 filed Sep. 21, 2004; U.S. Provisional Patent Application Ser. No. 60/616,071 filed Oct. 5, 2004; U.S. Provisional Patent Application Ser. No. ______ (Attorney Docket No. 16144US01) filed Oct. 5, 2004; U.S. Provisional Patent Application Ser. No 60/616,071, filed Oct. 5, 2004; U.S. patent application Ser. No. ______ (Attorney Docket No. 16223US02) filed ______; U.S. patent application Ser. No. ______ (Attorney Docket No. 16224US02) filed ______; and U.S. patent application Ser. No. ______ (Attorney Docket No. 16226US02) filed ______.
[0022] The above stated applications are hereby incorporated herein by reference in their entirety.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0023] [Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[0024] [Not Applicable]
BACKGROUND OF THE INVENTION
[0025] In video system applications, a picture is displayed on a television or a computer screen by scanning an electrical signal horizontally across the screen one line at a time using a scanning circuit. The amplitude of the signal at any one point on the line represents the brightness level at that point on the screen. When a horizontal line scan is completed, the scanning circuit is notified to retrace to the left edge of the screen and start scanning the next line provided by the electrical signal. Starting at the top of the screen, all the lines to be displayed are scanned by the scanning circuit in this manner. A frame contains all the elements of a picture. The frame contains the information of the lines that make up the image or picture and the associated synchronization signals that allow the scanning circuit to trace the lines from left to right and from top to bottom.
[0026] There may be two different types of picture or image scanning in a video system. For some television signals, the scanning may be interlaced video format, while for some computer signals the scanning may be progressive or non-interlaced video format. Interlaced video occurs when each frame is divided into two separate sub-pictures or fields. These fields may have originated at the same time or at subsequent time instances. The interlaced picture may be produced by first scanning the horizontal lines for the first field and then retracing to the top of the screen and then scanning the horizontal lines for the second field. The progressive, or non-interlaced, video format may be produced by scanning all of the horizontal lines of a frame in one pass from top to bottom.
[0027] In video compression, communication, decompression, and display, there has been for many years problems associated with supporting both interlaced content and interlaced displays along with progressive content and progressive displays. Many advanced video systems support either one format or the other format. As a result, deinterlacers, devices or systems that convert interlaced video format into progressive video format, have become an important component in many video systems.
[0028] However, deinterlacing takes fields from interlaced video and coverts them into frames of progressive video, at double the display rate. Certain problems may arise concerning the motion of objects from image to image during deinterlacing. Objects that are in motion are encoded differently in interlaced fields and progressive frames. Video images or pictures, encoded in interlaced video format, containing little motion from one image to another may be de-interlaced into progressive video format with virtually no problems or visual artifacts. However, visual artifacts become more pronounced with video images containing a lot of motion and change from one image to another, when converted from interlaced to progressive video format. As a result, some video systems were designed with motion adaptive deinterlacers.
[0029] Areas in a video image that are static are best represented with one approximation. Areas in a video image that are in motion are best represented with a different approximation. A motion adaptive deinterlacer attempts to detect motion so as to choose the correct approximation in a spatially localized area. An incorrect decision of motion in a video image results in annoying visual artifacts in the progressive output thereby providing an unpleasant viewing experience. Several designs have attempted to find a solution for this problem, but storage and processing constraints limit the amount of spatial and temporal video information that may be used for motion detection.
[0030] Frame rate defines how many pictures or frames of video information are displayed per second and the general units are frames per second (fps). In general, movies are shot at a frame rate of 24 fps. However, the standard promulgated in the United States by the National Television System Committee (NTSC) requires that information be displayed at a frame rate of 29.97 fps. Accordingly, the frame rate of movies shot at 24 fps must be changed in order to for them to be correctly displayed on NTSC compliant televisions. This process of changing the frame rate of movies from 24 fps to 29.97 fps is called telecine. Inverse telecine (IVTC) is the process utilized to transform movies from NTSC's frame rate of 29.97 fps back to a frame rate of 24 fps.
[0031] In displaying video on a screen, horizontal lines are displayed from top to bottom. A signal traces the display of the horizontal like from top to bottom of the screen. In old displaying devices, the tracing signal would take time to return to the top of the screen, to begin scanning again. The time it takes the tracing signal to get from the bottom of the screen to the top is called vertical blanking. These days, during the vertical blanking intervals, information may be inserted about the video such as, for example, whether text is added to the video (closed captioning and teletext), modes of display (widescreen mode, etc.), and other similar display-related information.
[0032] So in systems that use deinterlacers, the system detects pixels coming through the deinterlacer, and generates statistics on them to perform 3:2 pulldown or 2:2 pulldown. Problem may arise during blanking intervals, because when they go through the system, and they have nothing to do with the video itself, the information that is not relevant to the video information and pixels, may cause problems for the system that is looking for a 3:2 or 2:2 pattern.
[0033] If used, the data present within a vertical blanking interval of video can significantly affect the accuracy of one or more statistical measures used by a video processing system, such as an inverse telecine deinterlacing system that performs reverse 3:2 or 2:2 pull-down of video. The statistical measures may be utilized by a video system to handle discrepancies. Some statistical measures that are negatively affected when data resident in vertical blanking intervals is utilized, are frame-based statistical measures. A frame-based statistical measure may utilize all pixels in the frame, including those pixels resident within vertical blanking intervals.
[0034] Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.
BRIEF SUMMARY OF THE INVENTION
[0035] Aspects of the present invention may be seen in a system and method that process video data. The method may comprise determining a first portion of the video data containing information needed to determine video-related data, and generating the video-related data utilizing only the first portion of the video data. Determining the first portion may comprise determining a starting line of video data of the first portion, and determining an ending line of video data of the first portion. The video-related data may comprise statistics related to the video data.
[0036] In an embodiment of the present invention, the starting line of video data may comprise the first line of complete video data. Similarly, the ending line of video data may comprise the last line of complete video data.
[0037] The video data may comprise the first portion of the video data and a second portion of the video data. In an embodiment of the present invention, the second portion of the video data may comprise a vertical blanking interval.
[0038] The system comprises at least one processor capable of performing the method as described hereinabove that processes video data.
[0039] These and other features and advantages of the present invention may be appreciated from a review of the following detailed description of the present invention, along with the accompanying figures in which like reference numerals refer to like parts throughout.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0040] FIG. 1 illustrates a block diagram of an exemplary architecture for positioning of a motion adaptive deinterlacer, in accordance with an embodiment of the present invention.
[0041] FIG. 2 illustrates a block diagram of an exemplary vertical blanking interval (VBI) bypass system, in accordance with an embodiment of the present invention.
[0042] FIG. 3 illustrates a block diagram of one or more statistical computation blocks that utilize the VBI bypass system, in accordance with an embodiment of the present invention.
[0043] FIG. 4 illustrates a flow diagram of an exemplary method for bypassing or ignoring data that is present within vertical blanking intervals (VBIs), in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0044] Aspects of the present invention relate to processing video signals. More specifically, certain embodiments of the invention relate to a method and system for processing video by bypassing or ignoring data that is present within vertical blanking intervals (VBIs).
[0045] FIG. 1 illustrates a block diagram of an exemplary architecture for positioning of a motion adaptive deinterlacer, in accordance with an embodiment of the present invention. Referring to FIG. 1 , the deinterlacer system 100 may comprise a motion adaptive deinterlacer (MAD-3:2) 102 , a processor 104 , and a memory 106 . The MAD-3:2 102 may comprise suitable logic, code, and/or circuitry that may be adapted to deinterlace video fields. The processor 104 may comprise suitable logic, code, and/or circuitry that may be adapted to control the operation of the MAD-3:2 102 and to transfer control information and/or data to and from the memory 106 . The memory 106 may comprise suitable logic, code, and/or circuitry that may be adapted to store control information, data, information regarding current video fields, and/or information regarding prior video fields.
[0046] The MAD-3:2 102 may be capable of reverse 3:2 pull-down and 3:2 pull-down cadence detection which may be utilized in a video network (VN). The MAD-3:2 102 may be adapted to acquire interlaced video fields from one of a plurality of video sources in the video network and convert the acquired interlaced video fields into progressive frames, at double the display rate, in a visually pleasing manner.
[0047] The MAD-3:2 102 may be adapted to accept interlaced video input and to output deinterlaced or progressive video to a video bus utilized by the video network. The MAD-3:2 102 may accept up to, for example, 720x480i and produce, for example, 720x480p in the case of NTSC. For PAL, the motion adaptive deinterlacer (MAD) may accept, for example, 720x576i and produce, for example, 720x576p. Horizontal resolution may be allowed to change on a field-by-field basis up to, for example, a width of 720 . The MAD-3:2 102 may be adapted to smoothly blend various approximations for the missing pixels to prevent visible contours produced by changing decisions. A plurality of fields of video may be utilized to determine motion. For example, in an embodiment of the present invention, five fields of video may be utilized to determine motion. The MAD-3:2 102 may produce stable non-jittery video with reduced risk of visual artifacts due to motion being misinterpreted while also providing improved still frame performance. The MAD-3:2 102 may also provide additional fields per field type of quantized motion information which may be selectable in order to reduce the risk of misinterpretation. For example, up to three (3) additional fields or more, per field type, of quantized motion information may optionally be selected in order to reduce risk of misinterpreted motion even further. This may provide a total historical motion window of up to, for example, 10 fields in a cost effective manner. Integrated cross-chrominance removal functionality may be provided, which may aid in mitigating or eliminating NTSC comb artifacts. A directional compass filtering may also be provided that reduces or eliminates jaggies in moving diagonal edges. The MAD-3:2 102 may provide reverse 3:2 pull-down for improved quality from film based sources. The MAD-3:2 102 may also be adapted to support a variety of sources.
[0048] In operation, the MAD-3:2 102 may receive interlaced fields and may convert those interlaced fields into progressive frames, at double the display rate. A portion of the information regarding fields that occurred prior to the current field being deinterlaced may be stored locally in the MAD-3:2. A portion of the information regarding fields that occurred after the current field being deinterlaced may also be stored locally in the MAD-3:2. A remaining portion of the information regarding fields that occurred prior to and after the current field may be stored in the memory 106 .
[0049] The processor 104 may control the operation of the MAD-3:2 102 , for example, it may select from a plurality of deinterlacing algorithms that may be provided by the MAD-3:2 102 . The processor 104 may modify the MAD-3:2 102 according to the source of video fields. Moreover, the processor 104 may transfer to the MAD-3:2 102 , information stored in the memory 106 . The processor 104 may also transfer to the memory 106 any field-related information not locally stored in the MAD-3:2 102 . The MAD-3:2 102 may then use information from the current field, information from previously occurring fields, and information from fields that occurred after the current field, to determine a motion-adapted value of the output pixel under consideration.
[0050] In an embodiment of the present invention, bypassing the data within a vertical blanking interval may prevent a subsystem such as, for example, a system that may be used to perform statistical computations, from utilizing the VBI data.
[0051] The statistical measures herein described may be utilized to handle discrepancies in a video signal. For example, the statistical measures may be used to detect that the cadence or format of a received video may have suddenly changed. The change in cadence may be attributed to a “bad-edit” of the video, for example. The inverse telecine deinterlacing system may comprise a 3:2 and/or 2:2 phase lock detector (PLD). The inverse telecine deinterlacing system may accept interlaced video as an input and may output deinterlaced/progressive video. U.S. patent application Ser. No. 10/945,729 filed Sep. 21, 2004, describes a MAD-3:2 that may comprise an inverse telecine deinterlacing system, which may also perform reverse 3:2 pull-down. Such a system may be significantly affected when data present within a vertical blanking interval is not bypassed or ignored while determining statistical measures for a particular video image. As such, U.S. patent application Ser. No. 10/945,729 filed Sep. 21, 2004, is hereby incorporated herein by reference in its entirety.
[0052] FIG. 2 illustrates a block diagram of an exemplary vertical blanking interval (VBI) bypass system 200 , in accordance with an embodiment of the present invention. The VBI bypass system 200 may be used to bypass or ignore vertical blanking intervals within a video signal during processing by a video processing system. The video processing system may comprise an inverse telecine deinterlacing system that performs reverse 3:2 or 2:2 pull-down, for example. In an embodiment of the present invention, the VBI bypass system may accept data external to a VBI to be processed by a statistical computation block of the video processing system. The statistical computation block does not consider the VBI data. The statistical computation block may comprise hardware, software, or a combination thereof.
[0053] The VBI bypass system may comprise a counter 203 , a first register 207 , a second register 211 , a first comparator 215 , a second comparator 219 , and an AND gate 223 . A data bus 227 may be used as an interface to receive one or more values or signals used by the VBI bypass system. The video processing system may also comprise the data bus 227 . The counter 203 may be used to count the number of lines per frame or per field of the video. The counter 203 may utilize a clock signal referred to as a line clock 205 . The line clock 205 may be used to count each horizontal line or horizontal scan line of the video received by the video processing system. The counter 203 may also utilize a counter reset control signal 209 , which may reset the counter to 0 at the end of each frame or field. The data bus 227 may supply the line clock 205 and the counter reset control signal 209 .
[0054] The first register 207 may store a value that determines the stats start line of each of the one or more frames/fields of the video signal to be processed. The stats start line may comprise the first line of each of the one or more frames that is utilized by the statistical computation block. The first line may correspond to the first line of the active video or viewable image. The value stored into the first register 207 may be obtained by way of the data bus 227 . Similarly, the second register 211 may store a value that determines the stats end line of each of the one or more frames/fields of the video signal to be processed. The stats end line may comprise the last line of each of the one or more frames/fields that is utilized by the statistical computation block. The last line may correspond to the last line of the active video or viewable image. The value stored into the second register 211 may be obtained by way of the data bus 227 .
[0055] In an embodiment of the present invention, the stats start and end lines may be set to restrict a region of the viewable image. For example, statistics may be measured in a region that may be part of a picture in picture type scenario; another example may be removing the bottom portion of the screen where subtitles may be overlaid, which may have an adverse effect on statistics generation if not removed.
[0056] In another embodiment of the present invention, the stats start and end lines may correspond to a left and right columns, respectively, to further restrict (and provide greater control of) the window that is utilized for measuring statistics of the image.
[0057] The first comparator 215 may receive two inputs comprising the value stored in the first register 207 and the output of the counter 203 . The second comparator 219 may receive two inputs comprising the value stored in the second register 211 and the output of the counter 203 . The first comparator 215 may be configured to output a logical high signal when the line count provided by the counter 203 reaches the value stored in the first register 207 . As described hereinabove, the value stored in the first register 207 may determine the first line of each of the one or more fields/frames utilized by the statistical computation block. The second comparator 219 may be configured to output a logical high signal when the line count provided by the counter 203 is less than or equal to the value stored in the second register 211 . As described hereinabove, the value stored in the second register 211 may determine the last line of each of the one or more fields/frames utilized by the statistical computation block. When the line count is greater than or equal to the stats start line but less than or equal to the stats end line, the AND gate 223 may output a logical high signal. The AND gate 223 output may be termed a VBI bypass control signal 213 . The VBI bypass control signal 213 may be used to enable or control one or more statistical computations utilized within the statistical computation block, for example.
[0058] In an embodiment of the present invention, the VBI bypass control signal 213 may be used to enable any statistical computation system, subsystem, circuitry, hardware and/or software, etc., that performs a statistical measurement. The VBI bypass system 200 may be implemented using hardware, software, or a combination thereof. Therefore, the various aspects of the present invention are not limited to the representative embodiment described in FIG. 1 .
[0059] In an embodiment of the present invention, some lines of the frame/field may be partially video data and partially VBI. Such lines may be skipped when determining the statistical information associated with the frame/field. The first line in a frame/field that is completely video data may be used as the stat start line and the last line in a frame/field that is completely video data may be used as the stat end line.
[0060] FIG. 3 illustrates a block diagram of one or more statistical computation blocks 300 that utilize the VBI bypass system, in accordance with an embodiment of the present invention. U.S. Provisional Application Ser. No. ______ (Attorney Docket No. 16144US01) filed Oct. 5, 2004, discloses details concerning the statistical computation blocks shown. As such, U.S. Provisional Application Ser. No. ______ (Attorney Docket No. 16144US01) filed Oct. 5, 2004, hereby incorporated herein by reference in its entirety.
[0061] The per-pixel unexpected field motion block (or HL Pattern Block) 303 , bad weave detector subsystem block 307 , and statistics collection block 311 may utilize a VBI bypass control signal 301 such as, for example, the VBI bypass control signal 213 of FIG. 2 . The per-pixel unexpected field motion block (or HL Pattern Block) 303 may generate Frame_unexpected motion values associated with a frame or field, which approximates the total motion associated with pixels missing from the frame. The bad weave detector subsystem block 307 may generate Frame_IT_diff det values, which provides a measure of the frame inverse telecine difference. The statistics collection block 311 may generate histogram bins for calculation of sigma values associated with the frames and used in approximating the repeat fields of a 3:2 pull-down video signal distribution.
[0062] The VBI bypass control signal 301 may be used to enable one or more statistical computations provided by each of the three statistical computational blocks 303 , 307 , and 311 when the video comprises active video or viewable image video. For example, if the VBI bypass control signal 301 is at a logical high level, the three statistical computation blocks 303 , 307 , and 311 may be enabled to facilitate one or more statistical computations provided by these blocks. On the other hand, when the VBI bypass control signal 301 is at a logical low level, it may be used to disable the statistical computations provided by each of these statistical computation blocks 303 , 307 , and 311 when the video comprises any data located within the vertical blanking interval.
[0063] FIG. 4 illustrates a flow diagram of an exemplary method 400 for bypassing or ignoring data that is present within vertical blanking intervals (VBIs), in accordance with an embodiment of the present invention. The method may begin at a start block 401 , where video information may be received. At a next block 403 the stat start line of a frame/field may be determined, and the state end line of the frame/field may be determined at a next block 405 . At a next block 407 each horizontal line or horizontal scan line of the video received may be counted. The number of horizontal lines may then be compared to the stat start line, and if it is greater or the same a logical high signal may be output at a block 409 . Similarly, the number of horizontal lines may be compared to the stat end line, and if it is less or the same a logical high signal may be output at a block 411 . The outputs of blocks 409 and 411 may then be logically ANDed at a next block 413 . At a next block 415 if the result of the AND operation is a logic high, the VBI bypass control signal may be enabled, which may indicate that stats associated with the frame/field may be computed. As a result, whenever the process is within a VBI, the stat computations may be disabled to avoid erroneous computations. The method may then terminate at an end block 417 .
[0064] The method 400 may be performed by hardware, software, or a combination thereof. In an embodiment of the present invention, a deinterlacer system such as, for example, the deinterlacer system 100 of FIG. 1 may perform the method 400 of FIG. 4 .
[0065] Accordingly, the present invention may be realized in hardware, software, or a combination of hardware and software. The present invention may be realized in a centralized fashion in at least one computer system, or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system or other apparatus adapted for carrying out the methods described herein is suited. A typical combination of hardware and software may be a general-purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein.
[0066] The present invention may also be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which when loaded in a computer system is able to carry out these methods. Computer program in the present context means any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following: a) conversion to another language, code or notation; b) reproduction in a different material form.
[0067] While the present invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the present invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present invention without departing from its scope. Therefore, it is intended that the present invention not be limited to the particular embodiment disclosed, but that the present invention will include all embodiments falling within the scope of the appended claims. | A system and method that determine a portion of video data with relevant information about that video to be used in statistical calculations associated with the video. The method may comprise determining the starting line and ending line of the portion of video data with the relevant information. The remaining portion of the video data may comprise information that may contain no statistical information. The remaining portion may be a vertical blanking interval. | 7 |
BACKGROUND OF THE INVENTION
The subject of the invention is a heat generator able to burn high-sulfur fuels and which, in the form of a compact assembly, enables the production of useful heat to be separated from the desulfurization of the flue gases.
Strict regulations in protected zones govern emissions of sulfur oxides in the gaseous effluents from heat generators and forbid the use of high-sulfur fuels which, however, have definite economic advantages: this is the case for certain coals related to lignites, and for oil residues from refining processes.
Aside from downstream processes for treating fumes which generally apply to very-high-power facilities, in certain fossil-fuel-burning thermal units desulfurization is accomplished in the course of combustion by directly injecting a calcium-based absorbent (limestone, lime, dolomite, etc.) into the hearth.
This in situ desulfurizing process is considered principally for solid fuels, and its efficiency (between 30 and 60%) is a great contributor to the temperature distribution in the combustion chamber, while requiring substantial lime consumption (Ca/S ratio=Calcium/Sulfur ratio on the order of 3 to 4 moles/mole).
A different method consists of using so-called "dry ash" fluidized-bed boilers which operate at about 800°-900° C. and in which fuel and absorbent are placed in intimate contact.
In particular, within a "fast" or "circulating" fluidized bed having systematic recirculation of the solid particles, a very high rate of desulfurization can be obtained (85-90%) with relatively modest Ca/S ratios (1.5 to 2 moles/mole).
However, the self-desulfurizing circulating-bed heat generator poses a number of technological problems.
In particular, its reliability is closely linked to the strength of heat-exchanging tube bundles and to abrasion and corrosion phenomena.
The device proposed has the essential advantage of being reliable since it can be implemented by using tested techniques. Moreover, the generator according to the present invention is compact and takes up very little space.
The basic idea is based on the combination of three principal elements arranged such that the exchange surfaces are protected from the rapid flow of solid particles which are often the cause of rapid deterioration of these surfaces.
Thus, the generator proposed consists essentially of a hearth or combustion chamber, preferably with cold walls, a recovery boiler capturing the sensible heat of the flue gases, and an intermediate circulating bed with an insignificant internal exchange surface, whose function is to desulfurize the gases passing between the hearth upstream and the exchanger downstream.
"Cold wall" is understood herein to mean that the wall has means for extracting heat.
In general, the present invention relates to a great generator with a combustion chamber, a circulating bed, and a recovery boiler. According to the present invention, the circulating bed and combustion chamber have a common wall.
This common wall may have at least one orifice for feeding into the circulating bed a stream of primary fluid and/or at least one orifice for feeding into the circulating bed a stream of secondary fluid.
This common wall may be a cold wall. Likewise, other walls of the combustion chamber may be cold walls.
The various cold walls may have provision for circulation of a fluid.
According to the present invention, the circulating bed and the recovery boiler may have a common wall.
Likewise, the combustion chamber and the recovery boiler may have a common wall.
The walls of the circulating bed may have a coating made of a heat-insulating material.
The desulfurizing circulating bed whose entrained solid material is essentially, the absorbent, uses the hot gases coming from the hearth as a working fluid.
Since the temperature of the gases may vary with the generator load, the bed may be maintained at the optimum desulfurizing temperature (800°-900° C.) by injecting a makeup fuel into the reactor, whereby combustion takes place with the excess oxygen from the upstream hearth, possibly with additional fresh fuel.
The compactness of the generator according to the invention is achieved by original spatial distribution of the three main elements disposed vertically. This compactness facilitates its prefabrication. The present invention will be better understood and its advantages will emerge more clearly from the description hereinbelow of particular non-limitative examples illustrated by the attached figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the general layout of the heat generator according to the invention,
FIG. 2 is a simplified perspective view of such a heat generator, and
FIGS. 3 and 4 show two particular versions of the arrangement of the various elements of the heat generator.
DETAILED DESCRIPTION
The principle of the compact self-desulfurizing unit according to the invention is illustrated by FIG. 1, which shows a particular example adapted to combustion of a solid or liquid fuel injected in the powder form into the upstream hearth or combustion chamber.
Combustion chamber or hearth 1 is preferably cold-walled, whereby exchange surfaces 2 are for example of the "diaphragm wall" type, i.e. the fluid circulating means are associated and/or integrated with the walls of the combustion chamber. These cold walls are sized such that the temperature of the combustion gases at the end of the hearth may be in the range of 600°-850° C. for all operating modes.
Burner 3 may advantageously be a "low NO x emitting" burner to limit nitrogen oxide emissions and contribute to making the generator completely non-polluting.
Under these conditions, the excess air or excess fuel can be regulated such that the quantity of residual oxygen is at least equal to that necessary to effect the second combustion in circulating bed 16, which has a reactor 6 and a separator 10 which may be of the cyclone type.
Reactor 6 of circulating bed 16 is joined to hearth 1 by a common wall 17, communication between these two elements being accomplished directly by one or more passages provided in this wall. The stream 41 of primary gas supplying the circulating bed and coming from combustion chamber 1 enters through lower passage 4, while the stream of secondary gas enters through upper passage 5.
The internal walls 7 are made of a layer of refractory insulating material which may be thin abrasion-resistant and the heat losses are essentially recovered by the heat-conducting fluid which bathes the jacket of hearth 1.
In the example of FIG. 1, auxiliary fuel and/or the material absorbing sulfur oxides is/are injected through at least one orifice 9 in the lower part of reactor 6, which is the dense phase of the circulating bed. However, it will not be a departure from the scope of the invention to inject these products at another point in the circulating loop of the circulating bed, particularly by injecting one or both products into return leg 20.
The oxidizing gases or fumes 41 and 51 coming from the lower 4 and upper 5 passages defined above and serving as a working fluid and comburant for the circulating bed are injected on either side of the dense phase 18 of this bed.
The gases or fumes in primary stream 41 penetrate into dense phase 18 via a perforated grid 8 or any other device ensuring good distribution of the gases throughout the fluidized solids.
The gases or fumes in secondary stream 51 are injected into the transition zone or diluted zone of reactor 19, also known as the release zone. They may also be distributed through several orifices in a straight cross section or stepped cross sections relative to the circulating axis in reactor 6. The same applies to the introduction of the primary stream.
Controlled distribution by appropriate means such as fume flaps between primary stream 41 and secondary stream 51 allows the progress of combustion in reactor 6 to be controlled and the flow of solids swept outside dense zone 18 to be sent to recycling.
This recycling is effected by means of separator 10 which can conveniently be a cyclone as stated above. The recirculation rate is governed by a valve device 12 which may be of mechanical or hydraulic design, for example a fluidized siphon or "L valve."
The assembly of reactor 6, cyclone 10, and link leg 20, which constitutes desulfurizing circulating bed 16, is heat-protected by refractory insulating coatings 7 and 11.
The desulfurized gases 21 leave the upper part of separator 10 to feed recovery boiler 13 and give up heat energy to exchange surfaces 14 which may be made of tube bundles.
The fumes are finally evacuated via pipe 15 and sent to the filtration system not shown in the diagram, which may be of a type known to the individual skilled in the art.
The solid waste which has not been recycled or which has escaped separator 10 of circulating bed 16 may be drawn off at the bottom of the combustion chamber through orifice 22 which may be blocked by a valve 23, at the bottom of dense phase 18 of the circulating bed at the level of grid 8, through orifice 24 which may have a valve 25, and/or the bottom of the recovery boiler through orifice 26 which may be blocked by valve 27.
In the embodiment shown in FIG. 1 which relates to production of non-superheated steam, the heat-conducting fluid 28 such as a water-steam emulsion coming from the combustion chamber is sent to a pressurized container or tank 29 through a line 30. This tank, located at the top of the generator in the example of FIG. 1, also receives in this example water-steam emulsion 28a coming from recovery boiler 13 through line 30. The fluid stored in container 29 is transferred in the form of steam via a line 31 to a consumer system such as a turbine 32, a heating system, etc. The heat-conducting fluid, after giving up part of its energy and after condensation in a condenser not shown, is distributed by a valve means 33 between the heat-conducting fluid feed to tube bundles 14 of recovery boiler 13 and the heat-conducting fluid feed of the circuit bathing combustion chamber 1, whereby said circuit may have pipes forming an integral part of the walls of this combustion chamber or may be formed by a sheet of water.
The heat-conducting fluid is carried between the outlet of turbine 32 and valve 33 and the feed to tube bundles 14 and pipe 34 by pipes 35, 36, and 37 shown at least partially in dot-dashed lines. Of course, these pipes can be heat-insulated.
FIG. 2 shows an example of the practical implementation of a unit wherein optimum compactness has been achieved by setting hearth 1, reactor 6 of circulating bed 16, and recovery boiler 13 edge-to-edge.
The straight sections of these component parts are rectangular (see FIG. 3), which allows them to have close thermal contact with each other and minimizes fatal losses from the walls to the surrounding environment.
In FIG. 2, wall 17 is interrupted before reaching the lower part 38 of hearth 1 and the reactor of circulating bed 6, thus allowing simple creation of lower passage 4.
This figure does not show the cyclone, the heat-conducting fluid circulating pipes, or the burner.
Reference 39 designates the orifice allowing burner 3 to be set in place (FIG. 1).
Orifice 40 designates the outlet orifice from reactor 6 of the circulating flow 42 proceeding toward separator 10.
Reference 43 designates the inlet orifice for gases 21 coming from separator 10 and proceeding toward recovery boiler 13 (FIG. 1).
In the embodiment shown in FIG. 2, circulating bed 6 is not extended heightwise in the same way as hearth 1, but is interrupted in the front by wall 44. The latter is surmounted by a parallelepipedic casing 45 in direct communication with recovery boiler 13 which is also parallelepipedic in shape.
Orifice 46 corresponds to the link of leg 20 (FIG. 1) connecting separator 10 (FIG. 1) to the reactor of circulating bed 6 (FIG. 1).
FIG. 3 represents a cross section at the level of the reactor of the circulating bed of the generator shown in FIG. 2.
In this FIG. 3 we see that reactor 6 of circulating bed 16 is thermally isolated on its four faces by the material designated by reference 47. The combustion chamber has a plane wall 48 common to both reactor 6 of the circulating bed at 49 and to the recovery boiler at 50.
Recovery boiler 13 and reactor 6 of the circulating bed have a common wall 52 which is substantially perpendicular to plane wall 48.
FIG. 4 represents an alternate version of the device according to the invention wherein it is the recovery boiler 13 which has a plane wall 53 common to both hearth 1 and reactor 6 of the circulating bed.
Reference 54 designates the wall common to hearth 1 and reactor 6, whereby this wall can be substantially perpendicular to plane wall 53 of the boiler.
In FIG. 1, valve 33 can be controlled bearing in mind the power demand from turbine 32, the quantity of fuel consumed by burner 3, and/or the temperature of reactor 6 of the circulating bed.
Introduction of an auxiliary fuel into the circulating bed at 9 for example, although not essential, permits more flexible control of the temperature of the circulating bed. | Heat generator comprising a combustion chamber, a circulating bed and a recovery boiler. The circulating bed and the combustion chamber have a common wall. The present invention may be used to achieve the combustion of high sulphur content fuels. | 5 |
BACKGROUND OF THE INVENTION
Treatment of grassy surfaces, e.g., golf course putting greens, with liquid materials such as liquid fertilizers, pesticides, and the like, is presently effected by various methods. In one method, a hand-held spray nozzle connected to a remote tank by a supply hose is carried onto the surface and moved about by the operator to effect coverage. This method, while requiring a minimum of equipment, is laborious and results in non-uniform coverage since it is difficult for the operator to determine which areas have been treated resulting in some areas not being treated at all, with other areas receiving more than one application. Consequently, a non-uniform growth or other result is obtained which is not only unpleasing in appearance but, in the case of putting greens and the like, causes a non-uniform playing surface.
In another method, a wheeled, multi-nozzle sprayer connected to a remote tank by a supply hose is pushed over the surface by the operator. While this method permits a somewhat more accurate application of liquid to the surface, it is highly laborious, often requiring a second operator to pull the hose. Furthermore, non-uniform coverage still results since the degree of application is related to the walking speed of the operator.
A third approach has been to employ a vehicular sprayer having a supply tank communicating with multiple spray nozzles to direct liquid onto the surface. While utilization of a sprayer of this nature is fast and permits generally uniform coverage, it is difficult to operate within the confines of a putting green, tends to compact the surface due to the weight of the liquid causing ruts and inhibiting the growth of grass, and requires frequent refilling because of the inherent limits on supply tank capacity.
SUMMARY OF THE INVENTION
The present invention relates to a sprayer apparatus adapted for use in combination with a mower permitting uniform application of liquids to grassy surfaces while minimizing surface compaction, improving accuracy and uniformity of coverage, eliminating laborious hand manipulation of hose, and saving a substantial amount of labor due to the combined mowing and spraying operations.
The apparatus is comprised of a frame adapted for attachment to a conventional triplex greens mower; a liquid intake means for receiving liquid through a supply hose from a remote source, e.g., a wheeled supply tank; and a liquid discharge means associated with the intake means for discharging a liquid spray onto the surface being treated.
Preferably, the sprayer frame is formed of two sections, a first section being affixed to the mowing apparatus and a second section being releasibly mounted on the first section. In this manner, a substantial part of the sprayer apparatus may be readily detached from the mowing machine when not in use.
In order to eliminate the possibility of entanglement of the intake hose with the mowing machine or contact with the spray, the hose is preferably held away from the sprayer apparatus by way of a horizontally positioned boom which is pivotally mounted to swing approximately over the rearmost 180° of the mowing machine.
The liquid discharge means of the present apparatus is preferably comprised of a rearwardly projecting spray nozzle fixedly mounted on the mowing machine, it being understood that a plurality of nozzles positioned to form a common spray pattern may also be employed. The spray nozzle is designed and positioned on the mowing machine to spray an area immediately behind the mowing machine which is substantially equal in width to the swath cut by the mowing machine. Thus, when the operator mows the grassy surface, being guided by the edge of the unmowed area, a uniform spray will also be applied which is coextensive with the width of the mowed area.
Thus, it is the primary object of the present invention to provide an improved sprayer apparatus for use in combination with a mower, or the like.
It is a particular object to provide an improved spray for putting greens and the like, permitting application of liquids with improved accuracy and uniformity of coverage, minimization of surface compaction, and reduced labor requirements.
Other objects of the present invention, if not specifically set forth herein, will be apparent to the skilled artisan upon reading the detailed description of the preferred embodiment taken in conjunction with the drawings in which:
FIG. 1 is a schematic view of the preferred embodiment showing the sprayer attached to a typical triplex greens mower;
FIG. 2 is a partial view of the sprayer frame showing means for attachment of the sprayer to the mower chassis;
FIG. 3 is a plan view of a putting green illustrating the pattern of movement of the sprayer-mower over the green during operation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the illustrated embodiment, the sprayer apparatus is shown mounted upon a typical triplex greens mower. It is to be understood, however, that the sprayer apparatus may also be used in combination with other mowers or other suitable vehicles, and that the mower does not per se form part of the present invention.
As shown in the drawing, the mowing machine is comprised of a chassis 10 supported at the rear by steerable wheel 12 and at the front by drive wheel 14 and an opposed wheel, not shown. Steering of wheel 12 is effected with steering wheel 16 carried on steering arm 18, which is supported by chassis 10. A seat 20 is provided for the operator. Power is provided by engine 22, fed from gasoline tank 24. Cutting is effected by way of three mowing units positioned to cut a common swath having a given width, specifically, unit 26, unit 28, and a third unit, not shown.
The sprayer apparatus of the present invention includes a lower frame section, generally 30, mounted on chassis 10. As illustrated in detail in FIG. 2, frame 30 is comprised of a pair of sub-assemblies adapted to be mounted upon chassis 10 of the mowing machine. The first of these sub-assemblies is comprised of a horizontal chassis mounting bar 32 having a chassis mounting bracket 34 integral with its inner end, and an upright mounting bar 36 integral with its outer end. A sprayer mounting bar comprised of a rearwardly extending section 38 and an inwardly directed section 40 integral with the outward end of section 30 extends from bar 36. An assembly flange 42 is positioned at the end of section 40.
The second sub-assembly of frame section 30 is correspondingly comprised of an upright mounting bar 44, an inwardly extending horizontal chassis mounting bar 46 having a mounting bracket 34 to secure frame section 30 to chassis 10. A second sprayer mounting section comprised of a rearwardly extending horizontal bar 50 and an inwardly extending bar 52 having an assembly flange 54 at its inner end engageable with assembly flange 42 extends rearwardly from mounting bar 44 to complete, upon assembly, means for mounting a sprayer unit to be described hereinafter.
An upper frame section, generally 56, is supported by lower frame section 30. Section 56 is comprised of a pair of downwardly extending, parallel mounting sleeves 58 and 60 spaced for engagement over bars 36 and 44 of section 30. The upper ends of sleeves 58 and 60 are integral with opposed ends of horizontal support bar 62. A vertical support column 64 extends upwardly from the center of support bar 62, and is integral therewith at its lower end. Extending outwardly from column 64 in a plane with bar 62 are a pair of opposed support bars 66 and 68, supporting at their outer ends a pair of upright limit arms 70 and 72, respectively, which serve to limit the movement of travel of a boom, to be described hereinafter, to approximately the rearmost 180° of the mowing machine. Arms 70 and 72 are secured to bars 66 and 68 with hinged brackets 74 and 76 respectively, permitting lowering of arms 70 and 72 to permit movement to the boom in a forward direction, for example, during transportation or storage of the apparatus.
Liquid is supplied to the sprayer apparatus from a remote supply source such as a wheeled tank, T, located off of the surface being treated and pulled by a tractor or other vehicle, V, and is directed to the apparatus through reelable supply hose 78. Hose 78 communicates through a combination quick-coupling and shut-off valve 81 to a second hose 82 which, in turn, communicates with a horizontal boom 84 extending rearwardly from between arms 70 and 72. Kinking of hose 78 is prevented by spring 86 about hose 78. The end of boom 84 opposite hose 78 is secured between arms 70 and 72 in mounting bracket 86. The weight of boom 84 is balanced by counterweight 88 positioned at the end of support arm 90, which is secured to bracket 86 with mounting member 92 carrying compression springs 94 and 96.
Mounting bracket 86 is attached by fitting 98 to upright vertical spindle 100 which extends downwardly into bearing housing 102 and is rotatably mounted therein. Housing 102 is fixedly attached to the upper end of vertical column 64 of frame section 56 with mounting adapter 104.
Liquid is permitted to travel from boom 84 to the discharge portion of the sprayer apparatus, to be described hereinafter, by way of hose 106 attached to boom 84 by fitting 108. Hose 106 communicates through a release valve 110 to shut-off valve 112 operable between open and closed positions by way of cable 114 by operating lever 116. Alternative operating means may be employed. For example, valve 112 may be conveniently controlled by a foot pedal.
Discharge of liquid downstream from shut-off valve 112 is effected through flexible hose 118 extending from valve 112 to vertical pipe 120 held in a vertical position by mounting bracket 122 on horizontal bar 52. Pipe 120 is vertically adjustable by way of adjustment sleeve 124 integrally formed with mounting bracket 122. The lower end of pipe 120 communicates through regulator gauge 126 to horizontally positioned, rearwardly extending spray nozzle 128 which is adapted to discharge a spray of liquid to the rear of the mowing machine. The configuration of nozzle 128 and its position are designed to form a pattern of spray which, upon impingement on the surface being treated, has a width substantially equal to the width of the swath being cut by the mowing machine.
As illustrated in FIG. 3, the combined mowing and spraying of the putting green is effected by driving the mowing machine from one side of a putting green, P, along a plurality of alternate paths of movement arranged parallel relative to each other, with each alternate path of movement being located adjacent to a preceding path of movement, whereby the plurality of paths of movement are collectively operable to completely and uniformly treat the putting green surface. It is known to treat surfaces in a pattern of this nature as illustrated, for example, by U.S. Pat. No. 3,753,409 to Frazier, and putting greens are commonly mowed in this manner.
In operation, the operator drives the mowing machine across the putting green or other grassy surface in a manner shown in FIG. 3, cutting a swath. Liquid under pressure from tank T is directed through hoses 78 and 82 and the interior of boom 84. From boom 84, the liquid moves downwardly through flexible hose 106 to shut-off valve 112. When valve 112 is in an open position, the liquid moves through valve 112 into flexible hose 118, and downwardly through pipe 120 to be discharged through spray nozzle 128. Since spray nozzle 128 is of a configuration and position such that the pattern of spray upon contact with the surface has a width substantially equal to the width of the swath being cut, a uniform application of liquid is achieved as the operator mows the grassy surface.
It will be obvious to one skilled in the art that many modifications and variations may be made in the preferred embodiment described above without departing from the spirit and scope of the present invention. | An improved spraying apparatus for use in combination with a mowing apparatus is described which facilitates uniform application of a liquid spray to grassy surfaces while minimizing surface compaction, said apparatus being comprised of means for receiving liquid from a remote supply source and means for discharging a liquid spray onto the surface being treated, the spray pattern contacting said surface having a width substantially equal to the width of the swath cut by the mowing apparatus. | 8 |
The Government has rights in this invention pursuant to Contract No. DE-AC04-75P00789 between the U.S. Department of Energy and American Telephone and Telegraph Company.
FIELD OF THE INVENTION
This invention relates generally to use of high temperature superconductors in the development of non-hysteretic and hysteretic Josephson junctions through the deposition of a Tl-Ca-Ba-Cu-O (Tl) film on a LaAlO 3 substrate to form the non-hysteretic junction and then through the implementation on this structure of a thin dielectric layer over the Tl film of the non-hysteretic junction followed by a normal metal cap layer to form the hysteretic junction. To formulate the non-hysteretic junction, a step is artificially etched into the substrate prior to application of the Tl film to induce a grain boundary junction in the Tl film covering the step in the substrate. The subsequent growth of the film over the step produces a Josephson junction having good uniformity and quality where the uniformity is judged by the dependence of the critical current, I c , on the applied magnetic field, and the quality is measured in terms of the critical current density, J c , and the product of the critical current, I c , and the normal state resistance, R n ,, i.e. ,I c R n . In addition, this invention permits the Josephson junction to operate at a high critical temperature, T c .
Further processing of the non-hysteretic junction through the use of a multilayer technique produces an artificial capacitance capable of producing a TlCaBaCuO step-edge junction exhibiting large amounts of hysteresis at a temperature of 77K. Comparison of the parameters discussed above before and after the addition of the cap found that I c dropped by factors of 1.3-3 and R n increased by factors of 1.1 to 3 as a result of cap addition, suggesting some possible alteration of the grain boundaries properties on the implementation of the cap.
BACKGROUND OF THE INVENTION
An extremely important concern for applications of the recently discovered high temperature superconductors (HTS) has been the development of repeatable, reasonably high quality hysteretic and non-hysteretic Josephson junctions.
Non-hysteretic Josephson junctions have been demonstrated in HTS materials by a variety of microelectronic-compatible techniques. Most of the process development to date for these non-hysteretic Josephson junctions has involved engineering YBaCuO, as grown, grain boundary junctions into circuits located on the substrate in the layout; however, one alternate technique offers HTS junctions with at least a quasi-integratable process. The process involves artificially etching a step-edge into a substrate before YBCO film growth, as set forth in Daly, K. P. et al., Appl. Phys. Lett., Vol. 58, p. 543 (1991). If the step-edge angle is sufficiently steep and the step height to film thickness ratio is reasonable, grain boundary junctions form with good uniformity and yield. Epi-layer induced YBCO junctions are described in Char, K. et al., Appl. Phys. Lett., Vol. 59, p. 733 (1991). While not offering the full spectrum of applications of traditional tunnel junction technology, these devices have many potential uses including SQUIDs, Single Flux Quantum (SFQ) logic, shock-wave lines, and long-junction amplifiers.
Early Tl junction attempts relied on finding naturally occurring grain boundaries which is not reasonable for microelectronic applications. Indeed, other TlCaBaCuO junctions have relied on native grain boundaries, see e.g., Miklich, A. H. et al., Appl. Phys. Lett., Vol. 59, p. 742 (1991). These junctions lack the microelectronic-like nature of the inventive technique described herein; they are not as uniform, have a lower yield, and have lower figures of merit.
The grain boundary chemistry is very different in the various HTS materials such as YBaCuO (YBCO), BiSrCaCuO and related compounds (Bi), and TlCaBaCuO (Tl). The grain boundaries in the YBCO system tend to be loosely coupled and normal-conducting in nature. In poorly deposited films, this is the most common cause of poor electrical performance. In the Bi and Tl systems, the grain boundaries tend to be more insulating in nature possibly because the structure causes greater oxygen excesses in the boundaries. The Bi and Tl grain boundaries also tend to be more strongly linked in bulk material and superconducting property degradation in high magnetic is more the result of the material itself, rather than the grain boundaries, as with YBCO.
Because of the insulating nature of the boundaries of Tl materials, they are attractive for high performance junctions where a good insulating barrier is desired. If the grain boundaries can be weakened without destroying their material properties, successful high performance devices are possible. The growth of HTS material on the substrate step may be sufficient to weaken the boundaries and should not alter the fundamental boundary structure significantly.
The following documents are incorporated by reference: Morphology Control and High Critical Currants in Superconducting Thin Films in the Tl-Ca-Ba-Cu-O System, Ginley, D. S., Kwak, J. F., Venturini, E. L., Morosin, B. and Baughman, R. J., Physica C 160, 42 (1989), Fabrication of TlCaBaCuO Step-Edge Josephson Junctions with Hysteretic Behavior, Martens, J. S., Hietala, V. M., Zipperian, T. E., Vawter, G. A., Ginley, D. S., Tigges, C. P., Plut, T. A. and Hohenwarter, G. K. G., Appl. Phys. Lett., Vol 60, No. 8, pp 1013-1015, Feb. 24, 1992, and TlCaBaCuO Step-Edge Josephson Junctions, Martens, J. S., Zipperian, T. E., Vawter, G. A., Ginley, D. S., Hietala, V. M., and Tigges, C. P., Appl. Phys. Lett., Vol 60, No. 9, pp. 1141-1143, Mar. 2, 1992.
For non-hysteretic Josephson junctions, we have invented a step-edge process to produce repeatable, high quality Josephson junctions using the HTS materials of the TlCaBaCuO system. The Tl system is desirable because of its higher T c (up to 125K) compared to the more common YBa 2 Cu 3 O 7 system with its lower T c (92K), and its large value of the product I c R n incurred while operating at a temperature of 77K which is indicative of high junction quality. Testing of over 250 junctions produced using the subject process has resulted in a yield of over 70% at temperatures to 100K.
One way to create hysteretic Josephson junctions from available non-hysteretic high temperature superconducting junctions is to artificially add capacitance. Hysteretic HTS junctions open up the possibility for many circuits which operate above a temperature of 77K. Hysteretic junctions are needed for voltage-state latching logic, SIS mixers, and studies of the superconductor gap structure of HTS materials. In addition, the coupling of very fast Josephson junction signals to the nonsuperconducting world becomes simpler with hysteretic junctions.
It is thus an object of the invention to provide a HTS Josephson junction that operates at higher temperatures, is compatible with microelectronic techniques, has a high degree of quality, a high yield and good uniformity.
Another object of the invention is to provide a HTS Josephson junction with hysteretic properties through the addition of an artificial capacitor to the non-hysteretic Josephson junction.
SUMMARY OF THE INVENTION
The foregoing and other problems are overcome and the objects of the invention are realized by a process for formulating a non-hysteretic Josephson junction using HTS materials which results in a junction having the ability to operate at high temperatures while maintaining high uniformity and quality. The Josephson junction is formed by etching a step in a LaAlO 3 substrate and then depositing a thin film of TlCaBaCuO on the substrate, covering the step, and forming a grain boundary at the step and a subsequent Josephson junction. Once the non-hysteretic junction is formed, the next step is to add capacitance to the system. In the current embodiment, this is accomplished by adding a thin dielectric layer, LaAlO 3 , however, any dielectric which is chemically compatible with the superconductor and of low loss and relatively high dielectric constant will work. The implementation of the dielectric layer is followed by a cap layer of a normal metal where the cap layer is formed by first depositing a thin layer of titanium (Ti) followed by a layer of gold (Au). The dielectric layer and the normal metal cap are patterned to the desired geometry.
BRIEF DESCRIPTION OF THE DRAWING
The above set forth and other features of the invention are made more apparent in the ensuing Detailed Description of the Invention when read in conjunction with the attached Drawing), wherein:
FIG. 1 ia an illustration of the structure of the Tl non-hysteretic Josephson junction.
FIG. 2 is a graphic illustration of the voltage versus the current for the Tl non-hysteretic Josephson junction having a width of 10 micrometers and a film thickness of 200 nanometers at an operating temperature of 77K.
FIG. 3 is a graphic illustration of the voltage versus the current for the Tl non-hysteretic Josephson junction having a width of 10 micrometers and a film thickness of 200 nanometers at an operating temperature of 77K where the graph depicts the data with and without an applied 93.6 GHz electromagnetic field.
FIG. 4 depicts the critical current dependence, at a temperature of 77K, of a step-edge non-hysteretic Josephson junction having a width of 10 micrometers with a critical current density of about 4000 A/cm 2 and under the influence of an applied magnetic field instituted via an external control line.
FIG. 5 illustrates the structure of the hysteretic Josephson junction.
FIG. 6 is a graphical illustration of the current-voltage characteristics for a 5 micrometer wide hysteretic device where one curve represents the device under the influence of an applied magnetic field and the other curve represents the lack of an applied magnetic field.
FIG. 7 is a graphical illustration of the dependence of the critical current of a hysteretic Josephson junction on an applied magnetic field induced by a solenoid placed just above the junction where the field strength is represented by the solenoidal current.
FIG. 8 is graphical illustration of the transient response of one of the hysteretic junctions to an increase in the current above I c where the junction current was bias ramped while the junction voltage was monitored on a sampling scope. The fixture limited switching time (upper trace) was about 50 picoseconds while for a calibrated signal path (lower trace) the rise time is less than 20 picoseconds.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, the fundamental non-hysteretic invention is a process for forming a step-edge Josephson junction using HTS, TlCaBaCuO, materials. The step 1 is formed by argon ion milling of a crystal of LaAlO 3 to form a step-edge substrate 2. In etching the crystal, a 500 eV Ar + beam was employed in conjunction with a 0.25 mTorr chamber pressure and with a 70 degree C. sample temperature. Both Ti, Ni and ordinary photoresist masks (not shown) have been used with equivalent results. Step heights of 350 nm were achieved after 20 minutes of etching; however, the step 1 is typically 300 nm in height.
The TlCaBaCuO HTS film 3 was deposited on the crystalline substrate 2 by sequential e-beam evaporation or by sputtering followed by sintering in air, typically for 16 minutes at 850 C., while under a partial pressure of Tl-O, and then annealed in oxygen for about 10 minutes at a temperature of 750 C. This technique generally resulted in a nominal film thickness of between 300 to 400 nm. The film 3 exhibited complete c-axis orientation normal to the crystalline substrate but only partial a-axis orientation in the plane. The grain size of the film was typically over 100 micrometers and the film was generally smooth on a scale <50 nm with the phase being predominantly Tl 2 Ca 2 Ba 2 Cu 3 O 10 . Of the various test films deposited on their respective substrates, the critical temperature, T c was found to be in the range of 103-105K and the film, not the junction, experienced critical current densities of 3×10 5 to 5×10 5 A/cm 2 . Non-hysteretic junctions typically had critical current densities of 1-10 kA/cm 2 , and for 5 micrometer wide non-hysteretic junctions, the normal state resistance is on the order of 100 ohms. The disruption in film growth caused by the step 1 resulted in the single or multi-phase grain boundary formation in the film 3 at the desired location. Thus, by patterning the substrate 2 with a given circuit in mind, the circuit can be entirely lithographically defined without relying on the random formation of natural grain boundaries where needed.
To formulate the test devices for the subject Josephson junction the following additional steps were employed. Silver contacts (not shown) were e-beam evaporated and annealed at 400 degree C. An interlevel dielectric 4, about 1 micrometer thick, of hard-baked negative photoresist was used to protect the junctions and insulate the HTS level from the top normal metal layer. The top normal metal layer 5, 40 nm of Ti followed by 250 nm of Au, was patterned into control lines to test magnetic field dependence of the critical current and to aid in RF field coupling for Shapiro step observation experiments.
Of the wafers made to date, the critical current densities, J c , ranged from 500 A/cm 2 to 25kA/cm 2 with close correlation observed between local film thickness and J c . Among a group of 50 functional junctions on one wafer, the average J c was 5 kA/cm 2 with a maximum deviation of 0.74 kA/cm 2 . Junction widths ranged from 5-50 micrometers with the smallest ones having the lowest yield. The yield on the larger junctions was higher, about 80% on 50 micrometer junctions. These are technically long junctions, and an asymmetric I c vs. applied magnetic field behavior has been observed.
A functional junction is defined as having I c >1 microampere at a temperature of 77K and having the characteristics of a resistively shunted junction model (RSJ). FIG. 2 depicts a typical graphical point plot of the current, I, versus the voltage, V, for a specified film width and thickness 6; a best fit RSJ curve 7 is drawn showing good correlation. FIG. 3 also depicts a current versus voltage plot; however, in this case, the parameters are measured under the added conditions of incident radiation 8 and absent incident radiation 9. Again the RSJ-like shape is present and the Shapiro steps 10 are well defined. The cleanliness of the curve suggests that the junction is not acting as an incoherent array.
FIG. 4 illustrates the magnetic field dependence of the junction as it relates to small junction dependence. The quality of the fit suggests that the junction is uniform and the device is strongly dominated by a single junction.
The I c R n of all of the tested junctions was high, in excess of any previous results for YBCO, with the average for 50 junctions exceeding 1 mV at a temperature of 77K. The measured values for I c and R n did not differ significantly between the junctions tested.
The technological process for developing Tl step-edge non-hysteretic Josephson junctions is capable of producing high quality junctions with relatively high yield and good uniformity within a junction and across the wafer. The multilevel process allows for reasonable circuit complexity such as control lines, wiring etc., without adversely affecting the junction quality.
In order to get strong hysteresis in a Josephson junction, it is necessary to add a few tenths of a picofarad of capacitance to the non-hysteretic junction where the required capacitance is dependent on the normal state resistance and on the critical current of the non-hysteretic junction. The invention produces a hysteretic Josephson junction by adding the capacitance to the HTS step-edge junction described above.
FIG. 5 shows the addition of the capacitive elements to the non-hysteretic junction. The structure 13 must be kept as small as possible to avoid adding inductance or resistance which could lead to a large number of resonances. The estimated capacitive addition based on the structure 13 of FIG. 5 is approximately 0.1 to 0.3 picofarads depending on the local roughness of the Tl layer. To provide the additional capacitance, the LaAlO 3 layer 11 was RF sputtered, at 100 watts for an unheated substrate, on to the Tl film 3 to a thickness of about 35 nm. The normal metal cap 12 comprises a base layer of approximately 40 nm of Ti followed by a layer of approximately 250 nm of Au. These layers were deposited by electron beam evaporation and lift off. For the data expressed in FIGS. 6-8, the area of the metal cap 12, after standard lithographic definition and scribing, was about 25 square micrometers.
The current-voltage (IV) curves of the hysteretic Josephson junction 13 are depicted in FIG. 6. FIG. 6 represents a four-point measurement with the current sweep provided by a semiconductor parameter analyzer (not shown) and the voltage measured by a sensitive amplifier (not shown). As with the non-hysteretic Josephson junction, the hysteretic junction displayed Fraunhofer-like magnetic field dependence for the critical current, FIG. 7. The magnetic field, B, of FIG. 7 was applied in the direction indicated in FIG. 5, 14. The magnetic field dependence displayed little variation, except for scaling, as long as the field remained in the plane of the section of FIG. 5 and passed through the Josephson junction area 16. The estimated current density, J c , of the junction for FIG. 6 is about lkA/cm 2 ; however, there is some excess current that was not present in the non-hysteretic junctions. Excess current is defined as that remaining when the normal branch of the IV curve, FIG. 6, is extrapolated back to zero voltage.
In some of the test hysteretic Josephson junctions, the excess current grew to 0.25I c . The noise evident in the test parameters was higher than that observed for the non-hysteretic junction; this variation suggests that the additional processing steps employed to form the hysteretic junction may have introduced some inhomogeneities.
The parameter beta, β, is used to quantify the amount of observed hysteresis. The parameter beta is defined using the minimum value of the ratio I/I c , where I is measured on the hysteretic return path, backwards into the RSJ model. For hysteretic Josephson junctions, β will correspond to the standard McCumber β as is expressed by 4πeI c CR n 2 /h where e is the charge of the electron, h is Plank's constant, C is the effective capacitance and R n is the normal state resistance. The values of β experienced a wide variation which may be due to roughness of the Tl surface which changed the effective added capacitance. The observed values of β varied from 5 to greater than 1000 where the greater the value of β the more hysteretic the junction.
I c and R n measurements were conducted at two points in the process of formulating a hysteretic Josephson junction: at the non-hysteretic Josephson junction stage and at the hysteretic Josephson junction stage when the additive capacitance was added to the nonhysteretic junction. The results showed a drop in the measured value of I c by a factor of 1.3 to 3 and a drop in the R n by a factor of from 1.1 to 3. These changes suggested that the addition of the capacitive cap produced an interference with the grain boundaries. One possible reason for the disruption of the grain boundary is the bombardment of the non-hysteretic junction by energetic oxygen ions during the RF sputter deposition of the LaAlO 3 .
The switching speed of the hysteretic Josephson junction was also examined. FIG. 8 is a graphical plot of the hysteretic junction voltage response to a slow increase in bias current. A rise time to the first plateau of approximately 50 picoseconds was observed. To get a better estimate of the switching speed, calibrated time domain transmission (TDT) measurements were made using an adjacent control line (not shown). The junction was biased just below I c and the TDT step signal was applied to the control line. The TDT step signal suppresses I c to switch the junction into the voltage state depicted in the lower trace 16, FIG. 8. The junction switch time, under these conditions was measured at less than 20 picoseconds.
Thus, while the invention has been particularly shown and described with respect to exemplary embodiments thereof, it will be understood by those skilled in the art that changes in form and details may be made therein without departing from the scope and spirit of the invention. | A process for formulating non-hysteretic and hysteretic Josephson junctions using HTS materials which results in junctions having the ability to operate at high temperatures while maintaining high uniformity and quality. The non-hysteretic Josephson junction is formed by step-etching a LaAlO 3 crystal substrate and then depositing a thin film of TlCaBaCuO on the substrate, covering the step, and forming a grain boundary at the step and a subsequent Josephson junction. Once the non-hysteretic junction is formed the next step to form the hysteretic Josephson junction is to add capacitance to the system. In the current embodiment, this is accomplished by adding a thin dielectric layer, LaA1O 3 , followed by a cap layer of a normal metal where the cap layer is formed by first depositing a thin layer of titanium (Ti) followed by a layer of gold (Au). The dielectric layer and the normal metal cap are patterned to the desired geometry. | 8 |
FIELD OF THE INVENTION
The present invention relates to the telecommunications art, and has particular reference to a novel circuit for storing telephone numbers using non-volatile memory for dialing when needed. More particularly, the present invention involves the use of a one-touch dialing device that enables a user to dial a plurality of telephone numbers that come pre-programmed in a read only memory on an integrated circuit.
BACKGROUND
Many telephones available on the market today incorporate circuitry capable of dialing pre-selected telephone numbers. The conventional means for accomplishing this task consists of the touching of a single button that triggers the circuitry to access a desired telephone number that is stored in electronic memory. However, the electronic memory circuitry normally requires an outside power source to maintain the storage of the telephone numbers. This type of memory storage is called volatile memory.
It is well known that many individuals have an extremely difficult time programming pre-set telephone numbers in many modem telephone units. The degree of difficulty required to program these devices indicates a need for programming simplicity. A device that simplifies the programming and storage of pre-determined telephone numbers, the dialing process for these numbers, and the elimination of an outside power source, is an improvement over the conventional means for accomplishing standard telephone number dialing using pre-programmed dialing buttons.
The external power source for volatile circuits usually consists of a low-power battery or AC plug-in adapter into the telephone itself. However, a major drawback of volatile memory is the requirement that the electronic power source remain constant. If the external power source is interrupted by insufficient battery power, or a power outage due to an electrical storm, the entire electronic memory used for storing telephone numbers vanishes. Should a typical power loss occur, the entire electronic memory must be reprogrammed with telephone numbers.
Prior inventions have included circuitry to accomplish a non-volatile memory device capable of storing pre-determined telephone numbers. For example, U.S. Pat. No. 5,495,525 issued to Walker et al. ("Walker") teaches a device in which a pre-determined telephone number dialing circuit must be pre-wired. The Walker dialing circuit requires that a digital counter integrated circuit be pre-wired to an integrated dialing circuit so that the telephone number corresponds to a given wiring pattern. When the counter cycles through its full count in binary, the Walker dialing circuit dials a pre-determined telephone number, depending on how the wires have been arranged between the dialer circuit and the counter circuitry. A tremendous limitation on this method is that it precludes the user from changing the telephone number, unless the entire circuit is rewired to correspond to a new telephone number. Rewiring the circuitry requires not only knowledge of electronics and integrated circuits, it also requires that the circuitry not be hard wired on a printed circuit board.
Other patented devices discuss similar approaches to dialing pre-programmed telephone numbers. However, none of these patented inventions include a non-volatile memory circuit that allows the user the flexibility to change or update the pre-determined telephone number by simply changing or reprogramming a read only memory device. The flexibility to allow a user to change a single, or even multiple, telephone numbers is a substantial improvement over the prior art.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a device with electronic circuitry capable of automatically dialing a pre-determined telephone number by depressing a single key or button.
It is a further object of the present invention for the electronic circuitry to consist of a non-volatile memory circuit capable of storing a pre-determined telephone number.
It is a further object of the present invention for the non-volatile memory circuit to consist of a programmable micro controller integrated circuit containing a read only memory. The micro controller is easily removable and interchangeable from an integrated circuit bay on a printed circuit board.
It is a further object of the present invention for the micro controller to be pre-programmed with telephone numbers and other pertinent information required for dialing purposes.
It is a further object of the present invention for the electronic circuitry to work under pulse or tone dialing conditions.
It is a further object of the present invention for the electronic circuitry to utilize power from standard telephone power sources, rather than from an external power source such as a battery or AC power supply.
It is a further object of the present invention for the electronic circuitry to stabilize power for a short period of time from the standard telephone power source after a user activates the dialing button apparatus for before commencing the telephone number dialing sequence.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features that are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its structure and its operation together with the additional object and advantages thereof, will best be understood from the following description of the preferred embodiment of the present invention when read in conjunction with the accompanying drawings wherein:
FIG. 1 illustrates a schematic of the electrical circuit according to the present invention connected in the standard mode prepared for dialing a pre-determined telephone number;
FIG. 2 is a perspective view of the single touch, automatic dialing unit according to the present invention;
FIG. 3 is a top view of the device displaying the touch button that initiates the dialing sequence when depressed;
FIG. 4 is a front view of the housing for the device where RJ 45 telephone wires may be plugged in from both the telephone and a line coming from a standard telephone network respectively.
DESCRIPTION OF PREFERRED EMBODIMENTS
Described below is the preferred embodiment of the present invention. Many of the features of the different embodiments are fabricated in a similar manner. Where variances in the construction of the various embodiments exist, these variations will be discussed together in the same section.
Referring to FIG. 1, a non volatile telephone dialing circuit 31 is preferably hard wired to a printed circuit board. The non volatile telephone dialing circuit 31, is electrically coupled to the telephone network by a telephone network having six contacts respectively, such as a RJ45 female jack 1. Another connection 2 may be provided in order to electrically couple a telephone handset to the same telephone network connection. Female jack 1 receives a telephone wire equipped with a male RJ45 jack from a standard telephone network, while female jack 2 receives a telephone wire equipped with a male RJ45 jack from a standard telephone. Contacts one, two, four, five, and six from female jacks 1 and 2 are electrically coupled together. Contact three of female jack 1 is coupled to diodes 6 and 9 at a junction through resistor 333, while contact four of female jack 2 is electrically coupled to the junction of diodes 7 and 8. Contact three of female jack 1 is also coupled to contact four of female jack 2 through resistor 333 and 200 Volt MOV 13. The MOV 13 provides protection in the event of an electrical surge on the telephone line. Contact three of female jacks 1 and 2 are electrically coupled via a current limiting resistor 3. Resistor 3 is also coupled to a bridge rectifier 5 by a resister 333.
Power for the non volatile telephone dialing circuit 31 is derived from the telephone network line voltage. In the preferred embodiment, this is accomplished with a bridge rectifier 5 coupled to circuitry configured to allow power regulation and power control. The bridge rectifier 5 comprises of diodes 6, 7, 8, and 9 such that the cathodes of diodes 6 and 7 are electrically coupled together, the anodes of diodes 8 and 9 are electrically coupled together, and anode of diode 6 is electrically coupled to the cathode of diode 8, while the anode of diode 7 is electrically coupled to the cathode of diode 9. The junction of diodes 6 and 7 is electrically coupled to electrical ground. The diodes 6-9 can be Motorola 1N4004 diodes or the like.
Power is received at the collector of a pnp transistor 14 through the bridge rectifier 5 and the combination of a parallel resistor 15 and a zener diode 16. The junction of diodes 8 and 9 is electrically coupled to transistor 14 at the emitter. The base and emitter of transistor 14 are electrically coupled via parallel resistor 15. The base of transistor 14 is electrically coupled to the anode of zener diode 16, while the cathode of zener diode 16 is electrically coupled to ground. The collector of transistor 14 is electrically coupled to the collector of an npn transistor 17. The base and collector of transistor 17 are electrically coupled via parallel resistor 18. The base of transistor 17 is electrically coupled to the anode of zener diode 19, while the cathode of zener diode 19 is electrically coupled to ground.
An external button 70, as shown in FIG. 2, may be mechanically coupled to an electrical switch 21 establishes a mechanical, user-controlled input that initiates the operation of the non volatile telephone dialing circuit 31. Prior to depression of the external button 70, the telephone dialing circuit 31 is in a standby mode, transistor 14 has no base current and therefore no collector current to bias transistor 17, resistor 18, and zener diode 19 which establishes the supply voltage for other circuitry in the telephone dialing circuit 31.
Depression of the external button 70 closes the electrical switch 21 and establishes a bias for transistor 14. When current is supplied through transistor 14, Zener diode 19 and parallel resistor 18 establish the proper conditions for forward biasing transistor 17. The selection of the zener diode 19 and current limiting resistor 18 should be selected so as to properly bias the micro controller within the range required by the micro controller manufacturer. This selection should also take into account the voltage drop of the base-emitter junction of transistor 17. In the preferred embodiment the selection of these components establish a voltage of approximately 4.3 volts at the emitter of transistor 17. A resistor 100 is electrically coupled between the emitter of transistor 17 and the cathode of a diode representing a primary terminal of an optical relay 4 of which the anode and the second primary terminal is grounded. As the voltage at the emitter of transistor 17 rises, current through a resistor electrically coupled between the emitter of transistor 17 and the primary terminal of the optical relay 4 results in an off-hook condition for the circuit 31.
This voltage at the emitter of transistor 17 provides the supply voltage for the integrated micro controller 11 and the integrated dialer circuit 12. The micro controller 11, contains non-volatile memory in the form of read only memory (ROM). The ROM is typically pre-programmed to contain the telephone numbers that will be dialed when a user depresses the button that closes the electrical switch 21. The micro controller 11, contains sixteen pins for both input and output, as well as power and ground. The dialer chip 12 contains all the circuitry for performing dialing functions for the device 31. The preferred embodiment of micro controller 11 is a the Microchip PIC16C5X, while the preferred embodiment of the dialer circuit 12 is the National Semiconductor TP5088.
The manufacturer specifications of the micro controller and the dialer circuit provide the recommended circuitry necessary for basic operational conditions. Accordingly, the present invention has adopted those recommendations and are described hereafter.
Pin five of the micro controller 11 is electrically coupled to ground, while pin four of the micro controller 11 is electrically coupled to ground via capacitor 37, and to the emitter of transistor 17 via the parallel combination of diode 38 and resistor 39. Capacitor 37 and resistor 39 create a turn on transient. The purpose of the turn on transient is to prevent micro controller 11 operation until the bias voltage as stabilized. Diode 38 is added to clamp the voltage at pin four of the micro controller 11 to the bias voltage at the emitter of transistor 17 to prevent damage to the micro controller 11 by high voltages stored on capacitor 37. In the preferred embodiment, the zener diode 19 and the parallel resister 18 are selected so that the bias voltage after transistor 17 is approximately 4.3 Volts D.C.
Pins sixteen and fifteen of the micro controller 11 are electrically coupled to a first oscillator circuit 32. The oscillator circuit 32, when combined with the internal circuitry of the micro controller create a system clock for the micro controller 11. The oscillator circuit 32 comprises a crystal 33, having a cathode and an anode, a resistor 34, and a pair of capacitors 35 and 36 respectively. The preferred crystal has a resonant frequency of 500 kHz and is electrically coupled to ground at its anode by capacitor 36, and by capacitor 35 at its cathode at the other end. Pin fifteen of the micro controller 11 is electrically coupled to resistor 34 in series with the cathode of crystal 33, while pin sixteen of the micro controller 11 is electrically coupled to the anode of crystal 33.
Pin ten of the micro controller 11 is electrically coupled to ground via resistor 45. Additionally, pin ten is also electrically coupled to pin two of the dialer circuit 12. Pin two of the dialer circuit 12 can then be controlled by the output of pin ten of the micro controller 11 but have a default condition of being grounded or at logic low. This prevents the dialer circuit 12 from producing output until the micro controller 11 has stabilized and is ready to dial.
Once the turn on transient has expired, the bias voltage at the emitter of transistor 17 is presumed stable and the micro controller 11 initiates the program code that takes control of the telephone dialing circuit 31.
As initiated by the program code, the micro controller asserts a positive voltage on pin thirteen. This forward biases npn transistor 20 and draws sufficient current to keep transistor 14 forward biased. This allows the circuit 31 to operate without having to keep the button of the electrical switch 21 depressed. Pin thirteen of the micro controller 11 is tied to the base of transistor 20 via series resistor 44. The collector of transistor 20 is electrically coupled to the base of transistor 14 via series resistor 22, while the base of transistor 20 is electrically coupled to ground via series resistor 23. The emitter of transistor 20 is also tied to ground. The terminals of the electrical switch 21, and a jumper switch 24 provided for test purposes, are electrically coupled in parallel across the collector and emitter of transistor 20.
Operation according to the program code continues as the status of switch 42 and switch 43 are determined. If switch 42 is in the open position, the circuit 31 is set for pulse dialing. If switch 42 is in the closed position, the circuit 31 is set for tone dialing. Switch 43 allows the user to select from two possible pre-programmed telephone numbers stored in the ROM of the micro controller 11 depending on whether it is in the open or closed position. Pin two and seventeen of the micro controller 11 are electrically coupled to ground via jumper switches 42 and 43, respectively. Pin two and seventeen of the micro controller 11 are also electrically coupled to the bias voltage at the emitter of transistor 17 via series resistors 40 and 41, respectively. When jumper 42 is in the closed position, pin two of the micro controller 11 grounded. When jumper 43 is in the closed position, pin seventeen of the micro controller 11 is grounded.
A second oscillator circuit 49, with a crystal 50 having a cathode and an anode, and capacitors 51 and 52, are electrically coupled to pins six and seven respectively of the dialer circuit 12. As required by the design and specification of the dialer circuit 12, the resonant frequency of the crystal is 3.50 MHz. The cathode of crystal 50 is electrically coupled to ground via capacitor 51 and is electrically coupled to pin six of the dialer circuit 12. The anode of crystal 50 is electrically coupled to ground via capacitor 52 and is electrically coupled to pin seven of the dialer circuit 12. Pin five of the dialer circuit 12 is tied directly to ground.
At the appropriate time as determined by the executable program in the ROM of micro controller 11, and depending on the status of the switches 42 and 43, the micro controller 11 begins transmitting information via pins six through nine of the micro controller 11 which are electrically coupled to pins nine through twelve of the dialer circuit 12 respectively.
Output from the dialer circuit 12 is buffered by the composition of transistor 25 and surrounding circuitry. Pin fourteen of dialer circuit 12, is electrically coupled to the base of transistor 25 by a series combination of capacitor 46 and resistor 47 in parallel with resistor 48 which is then electrically coupled directly to ground. The collector of transistor 25 is electrically coupled to the collector of transistor 14. The tones generated by the dialer circuit 12 are thereafter imposed on the telephone line through the emitter current of transistor 14, the diodes of the bridge rectifier 5, and the resistors 333 and 3.
As the program in the ROM of micro controller 11 executes, and the information is transmitted between the two circuits 11 and 12, the circuit 31 executes a standard dialing sequence (get dial tone, dial numbers, ring telephone until answer is received from other telephone). When the dialing sequence is complete, the telephone dialing circuit 31 shuts down. First the micro controller asserts a low voltage on pin thirteen thereby cutting off transistor 20. Transistor 20 is electrically coupled to pin thirteen of the micro controller 11 by a resistor 55. As a result, transistor 14 has no base current and thereby stops supplying current to transistor 17. As the voltage at the emitter of transistor 17 begins to collapse, the micro controller asserts a high voltage on pin twelve resulting in a forward bias of npn transistor 27. Transistor 27 is electrically coupled to pin twelve of the micro controller 11 by a resistor 44. This effectively discharges capacitor 30 and disables the micro controller 11 and resets the optical relay 4 so that the telephone dialing circuit goes back to a on-hook condition. A path to electrical ground for any remaining charge at the emitter of transistor 17 is provided by resistor 56. Thus the circuit 31 is returned to its original state, and all power is shut off to the circuit 31.
Referring to FIG. 2, the figure displays a housing 54, with the button 70 which controls the electrical switch 21 of FIG. 1, located in the approximate middle of the housing 54. When the button 70 is depressed, it activates the circuit 31 of FIG. 1 to dial the pre-determined telephone number stored in ROM. Referring to FIG. 3, the figure displays the pair of female RJ45 jacks 1 and 2 respectively, where a standard telephone line equipped with male jacks may be inserted to connect circuit 31 of FIG. 1 to the telephone network. Referring to FIG. 4, the figure displays the frontal view of the RJ45 jacks 1 and 2.
It is understood that those skilled in the art may conceive modifications and/or variations to the specific embodiments shown and described herein. Any such modifications or variations which fall within the purview of this description are intended to be included therein as well. It is understood that the description herein in intended to be illustrative only and is not intended to be limiting. Rather, the scope of the invention described herein is limited only by the claims appended hereto. | An automatic telephone number dialing circuit powered from a standard telephone network wire for storing telephone numbers using non-volatile memory including a one-touch dialing device that enables a user to automatically dial a plurality of telephone numbers that are pre-programmed in non-volatile read only memory of an integrated circuit. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to an induction heating roller device, a heating roller for the induction heating roller, a fixing apparatus and an image forming apparatus.
A heating roller, which includes a thermal source composed of a halogen lamp, has heretofore been employed to thermally fix toner image onto record medium. Such a technology encounters an issue such as a prolonged warm-up time or an insufficient thermal capacity. To address this issue, considerable research and development work has been undertaken in the past to commercially apply an induction heating technology.
Japanese Patent Publication NO. 2000-215974 discloses an excitation coil located in close proximity to an object body to be heated for causing induction current to flow through the object body, with the excitation coil including a coil wire material wound in a plane and deformed in a shape to cope with a curved wall of the object body while a magnetic core is located in a position opposed to the object body with respect to both ends of the excitation coil in a longitudinal direction thereof such that the magnetic core cope with a curved surface of the excitation coil. (Related Art 1) Japanese Patent Publication NO. 2000-215971 discloses an induction heating device which includes a heating rotor body having an electromagnetic induction heating property, and a magnetic flux generating unit located inside the heating rotor body for generating magnetic flux of a high frequency to cause the heating rotor body to be heated up due to an electromagnetic induction heating for thereby heating the object body, with the magnetic flux generating unit including a core, made of magnetic material, and an electromagnetic transducer coil wound around the magnetic core, which is comprised of a core portion around which the electromagnetic transducer coil is wound, and a magnetic flux induction core portion opposed between distal ends portions in a magnetic flux gap for concentrating a magnetic flux at a portion of the heating rotor body more intensively than that concentrated at the core portion. (Related Art 2)
Any one of the Related Arts 1 and 2 employs a heating technology that uses an eddy-current loss which provides the same effect commercially realized in an IH cooker. A high frequency electric current to be utilized in such a heating technology is selected to have a frequency ranging from 20 to 100 kHz.
On the contrary, Japanese Patent Publication NO. 59-33787 discloses a high frequency induction heating roller which is comprised of a cylindrical roller body composed of electrically conductive material, a cylindrical bobbin located inside the cylindrical roller body in a concentric relationship, and an induction coil wound around an outer circumferential periphery of the bobbin in a spiral relationship to induce induction current in the roller body to compel it to be heated up. (Related Art 3)
With such a structure of the Related Art 3, the cylindrical roller body serves as a secondary coil of a closed circuit and the induction coil serves as a primary coil, with the primary and secondary coils being coupled in a transformer relationship to cause secondary voltage to be induced in the secondary coil of the cylindrical roller body. The presence of flow of secondary electric current through the closed circuit of the secondary coil responsive to the secondary voltage compels the cylindrical roller body to be heated up, i.e. in a so-called secondary side resistance heating technology. With this technology, the presence of stronger magnetic coupling than that achieved in the heating technology using the eddy-current loss increases a stationary efficiency while enabling the whole of the heating roller to be heated up, resulting in an advantage wherein a fixing device becomes more simple in structure than those of the Related Arts 1 and 2.
However, the Related Art 3 encounters an issue wherein a warm-up time can not be so shortened as expected. Upon considerable research and study conducted by the inventor, such an issue is deemed to originate from the resistance value of the secondary coil formed in the heating roller, which is not supervised.
In the Related Art 3, further, with the use of such a low frequency ranging from 20 to 100 kHz that is obtained in an IGBT inverter that is used in cooking equipments such as an induction heating type cooker or range, it is difficult for a high electric power transmitting efficiency to be obtained.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an induction heating roller device and a heating roller for the induction heating roller device, and a fixing apparatus and an image forming apparatus, using such component parts, which are able to obtain a high electric power transmitting efficiency.
It is another object of the present invention to provide an induction heating roller device and a heating roller for the induction heating roller device wherein the heating roller has a temperature distribution as uniform as possible, a fixing apparatus and an image forming apparatus using such component parts.
According to a first aspect of the present invention, there is provided an induction heating roller device which comprises an induction coil unit having a primary coil, and a hollow heating roller having a secondary coil coupled to the primary coil of said induction coil unit through a coreless transformer coupling and having a secondary resistance value substantially equal to a secondary reactance, said heating roller being rotatably supported. Further, the secondary coil may be formed of a closed circuit.
The present invention will be described hereinafter in conjunction with terminologies based on the following definitions and technical meanings.
Induction Coil Device
The induction coil device is energized, i.e. excited with an alternating electric power supply and, more preferably, with a high frequency output of a high frequency electric power supply. Alternatively, the induction coil unit is comprised of the primary coil which is coupled with the secondary coil of the heating roller through a core-less transformer coupling. The primary coil may be held stationary with respect to the rotating heating roller or may be rotated either together with the heating roller or separately from the same. Also, when it is desired to rotate the primary coil, a rotational current collecting mechanism may be located between the alternating current power supply and the induction coil unit. The “core-less transformer coupling” means not only a complete core-less transformer coupling but also a transformer coupling which seems to remain in a substantially core-less relationship.
Further, the induction coil unit may be comprised of a coil bobbin for supporting the primary coil. The coil bobbin may be formed a winding recess for achieving well-ordered winding of the coil.
Furthermore, the induction coil unit allows the primary coil to be formed in a single coil component or in a plurality of coil components. In case of the primary coil composed of the single coil component, the primary coil may be located at a substantially central area of the heating roller. In case of the primary coil composed of the plurality of coil components, the plural coil components may be equidistantly distributed over the surface of the heating coil along an axis thereof. And, respective primary coil components may be connected to the alternating current electric power supply in parallel to one another.
Heating Roller
The heating roller includes the secondary coil which is coupled with the primary coil through the core-less transformer coupling. And, the closed circuit has the secondary resistance value which is substantially equal to the secondary reactance of the secondary coil. Further, the secondary coil may be formed in a closed circuit. In this connection, an expression that the secondary resistance value and the secondary reactance are “substantially equal” to one another is meant by the fact that, when the secondary resistance value is expressed as R a and the secondary reactance is expressed as X a and when α=R a /X a , a formula 1 is satisfied. The reason why such a formula is defined will be described below in detail. Further, the secondary resistance value can be obtained by measurement. The secondary reactance can be obtained by calculation of the formula 1.
0.1<α<10 [Formula 1]
Further, the heating roller includes the secondary coil which may be formed in a single coil component or in a plurality of coil components. When forming the plurality of coil components as the secondary coil, it is preferable for the plurality of coil components to be dispersedly located on the heating roller along its axial length. In order to support the secondary coil, it may be possible to employ the roller base body made of electrically insulating material. And, the secondary coil may be located on the inner or outer circumferential peripheries of the roller base body or may be internally located in the roller base body.
Furthermore, the heating roller may be rotated with a mechanism composed of suitably selected one of various related art structures. Also, when thermally fixing toner image onto record medium, the pressure roller is located in direct opposition to the heating roller, with record medium, which is formed with toner image, being transferred through between the two rollers such that the toner image is heated and melted to the record medium.
OPERATION OF THE PRESENT INVENTION
With the structure of the present invention discussed above, a highly improved electric power transmission efficiency is obtained between the induction coil unit and the heating roller. Such a reason is described below in detail.
First, an equivalent circuit of the induction heating roller device is considered in conjunction with FIG. 1 .
FIG. 1 shows a circuit diagram illustrating an equivalent circuit of the induction heating roller device according to the present invention.
In FIG. 1 , a reference symbol Z ca designates an input impedance as viewed from the primary coil wp, a reference symbol X a designates reactance of the secondary coil ws, a reference symbol Ra designates a secondary resistance value and a reference symbol k designates a coupling coefficient of the primary coil wp and the secondary coil ws
The input impedance Z ca as viewed from the primary coil wp is expressed by the following formula 2:
Zca = k 2 · Xc · Ra · Xa Ra 2 + Xa 2 + j · Xc · ( 1 - k 2 · Xa 2 Ra 2 + Xa 2 ) [ Formula 2 ]
The ratio between the real part and the imaginary part of the formula 2, i.e. Q ca =ImZ ca /ReZc a is expressed by a formula 3.
Qca = ( Ra Xa ) 2 + 1 - k 2 ( Ra Xa ) · k 2 [ Formula 3 ]
Here, to execute variable arrangement, when substituting R a /X a =α for the formula 3, a formula 4 is obtained as:
Qca = α 2 + 1 - k 2 α · k 2 [ Formula 4 ]
When conducting a search for variation in Q ca based on the primary coil while varying α for each coupling coefficient using the formula 4, Q ca varies as shown in FIG. 2 .
FIG. 2 shows a graph illustrating the relationship between α and Q ca for each coupling coefficient for illustrating the operating principle of the induction heating roller according to the present invention.
In FIG. 2 , the abscissa axis designates α and the axis of ordinates designates Q ca .
As shown in FIG. 2 , the larger the coupling coefficient k, the smaller will be the value of Q ca based on the primary coil. Further, there exists one a which makes Q ca , based on the primary coil, to have the minimum value for each coupling coefficient. As a consequence, when the inductance remains in a fixed value due to the heating roller with a structure which is determined, it is understood that optimization of α is synonymous with optimization of the secondary resistance value.
Now, the electric power transmission efficiency is calculated using Q ca based on the primary coil. Also, in order to simplify calculation and to make only the electric power transmission efficiency to be at stake, the amount of heat transfer due to radiation and convection is omitted and it is assumed that energy, which can not be directly transferred to the secondary coil of the heating roller through the magnetic coupling, disappears completely.
Let consider about Q ca based on the primary coil separately for a first case when the heating roller is located at the secondary side, i.e. Q L during a loading state and for a second case when measurement is enabled for the independent primary coil, i.e. Q U during an unloading state. The primary coil has power factors determined before and after the induction coil unit is inserted through the heating roller, i.e. power factors determined before and after the loading and unloading states, with the power factors varying responsive to the load as expressed by formulae 5 and 6.
cos{tan −1 (Q U )} [Formula 5]
cos{tan −1 (Q L )} [Formula 6]
When supplying electric power P c to the primary coil, apparent power P r of the primary coil is expressed as follows.
P r =P c cos{tan −1 ( Q L )} [Formula 7]
Here, as the coupling coefficient k is small, the power factor vary in a small range before and after the loading state such that the loss P loss caused by the apparent power P r of the primary coil is expressed by approximation determined by the following formula.
P loss ≈P r ·cos{tan −1 (Q U )}= P c ·cos{tan −1 ( Q U )}/cos{tan −1 (Q L )} [Formula 8]
Calculating the power transmission efficiency η c using the formula 8 compels it to be expressed by formula 9.
η c ≈1 −P loss /P c =1−cos{tan −1 (Q U )}/cos{tan −1 ( Q L )} [Formula 9]
The formula 9 represents that when the power factor cos {tan −1 (Q L )} of the primary coil during the unloading state or when the load is not connected to the primary coil remains at a fixed level, as the power factor cos {tan −1 (Q L )} of the primary coil during the loading state or when the load is connected to the primary coil decreases, the electric power transmission efficiency η c of the primary coil decreases. The presence of the power factor remaining at a low level during mounting of the load means that Q L is large.
Now, the range of magnitude Q L during mounting of the load is described below in detail with reference to FIG. 3 .
In FIG. 3 , a reference symbol IC designates an induction coil unit, a reference symbol TL designates a transformer coupling type load and a reference symbol EL designates an eddy-current loss type load.
The induction coil unit IC is comprised of a bobbin CB and the primary coil wp. The bobbin CB is composed of a cylindrical member having an outer diameter of 17.7 mm and a length of 120 mm. The primary coil wp is composed of an electrically insulated soft copper wire, having a diameter of 1.5 mm, tightly wound on the bobbin CB in twenty turns and has a coil diameter of 20.7 mm, a coil length of 30 mm and a wire length of 140 mm. Further, distal ends of the primary coil wp extend rearward from a distal end of the bobbin CB by a distance of 3 mm. Also, “the wire length” refers to a distance between a distal end of a wire pair WP and the distal end of the bobbin CB.
The transformer coupling type load TL forms a heating roller which has been employed in practical use for a halogen lamp type heater and includes a cylindrical body, made of iron, which has an outer diameter of 30 mm and an inner diameter of 25 mm, with an outer circumferential periphery of the cylindrical body being covered with a plastic resin layer of a thickness of 4 mm. Thus, the iron cylindrical body forms the secondary coil.
The eddy-current loss type load EL is prepared as a comparison example and is composed of stainless steel plate having a length of 300 mm, a width of 400 mm and a thickness of 2 mm.
With the conditions given above, the inductance of the primary coil wp of the induction coil unit IC during the non-mounting state of the load is measured, with a measured result being plotted in FIG. 4 .
FIG. 4 is a graph illustrating the variations in the inductance and the coupling coefficient of the primary coil, during the non-mounting state of the load in a preliminary test conducted for confirming the operating principal of the induction heating roller unit, plotted in terms of a measured frequency.
In FIG. 4 , the axis of abscissa designates the measured frequency (MHz), and the left and right of the axis of ordinates designates the inductance (μH) and the coupling coefficient, respectively. A curve A indicates the inductance, and a curve B indicates the coupling coefficient.
As is apparent from FIG. 4 , the inductance remains at a substantially fixed level of about 4.3 μH in the measured frequency range. Accordingly, it appears that such a primary coil is less affected with a distribution capacity to be suitably employed for the induction coupling. Further, when obtaining the coupling coefficient from the inductance before and after the mounting of the primary coil wp with respect to the transformer type load TL by calculation, it is confirmed as shown in the graph that the coupling coefficient remains at a substantially fixed level of about 0.5 in the measured frequency range. Accordingly, under a condition where the secondary impedance is fixed, it appears that a terminal impedance based on a primary conversion can be designed to be substantially dependent on the operating frequency. In addition, when obtaining Q during the non-mounting state of the load, it varies as shown in FIG. 5 .
FIG. 5 is a graph illustrating the variation of Q U in terms of the measured frequency of the primary coil during the non-mounting state of the load in the preliminary test conducted for confirming the operating principal of the induction heating roller unit, plotted in terms of a measured frequency.
In FIG. 5 , the axis of abscissa indicates the measured frequency (MHz), and the axis of ordinates indicates Q U .
As will be appreciated from the graph in FIG. 5 , Q U of the primary coil wp has a maximum level at the frequency of about 3 MHz. Accordingly, the primary coil wp has the minimum loss at the frequency of 3 MHz.
By the way, Q U of the primary coil has a value of 62 at the frequency of 3 MHz as seen from the graph. On the other hand, in FIG. 2 , when the coupling coefficient is 0.5, the minimum Q ca , i.e. Q L is 7 with α≈1. As a consequence, calculating the electric power transmission efficiency η c with the minimum Q L of the primary coil employed in the presently conducted test using the formula 9 results in a value of 88.6%. On the contrary, since the maximum Q L with the coupling coefficient of 0.5 has a value of about 53, calculating the electric power transmission efficiency η c with the condition given above in a similar manner results in a value of 14.7%.
From the foregoing results, it appears that optimization of the secondary resistance value enables the electric power transmission efficiency to be increased. In this connection, the optimization is meant that R a is nearly equal to X a . And, although a phrase in that “R a is nearly equal to X a ” is meant that R a remains in a range of 0.1 to 10 times X a as will be understood from the formula 1 discussed above, such an allowable range refers to a range which enables a high level of the electric power transmission efficiency to be obtained when taking the resistance temperature coefficient of the secondary coil and the product variations thereof as well as the temperature rise of the heating roller into consideration. More preferably, the number of times is in a range between 0.25 and 4. Even further preferably, the number of times is in a range between 0.5 and 2.
Next, a description will be given to the eddy-current loss type load EL which serves as the comparison. Q U and Q L of the primary coil wp have been measured by separating the primary coil wp of the induction coil unit IC apart from the eddy-current loss type load EL or compelling the primary coil to approach an area spaced by a distance of 3 mm from the load EL. As a result, the coupling coefficient was 0.303 and was clearly less than that of the transformer type load. Also, Q U and Q L of the primary coil had the relations Q U =7.4 and Q L =5.4. Then, calculating the electric power transmission efficiency using the formula 9 has resulted in a value of 26.0%. Also, the measurement has been conducted with the frequency of approximately 40 kHz in practical use. Since the actual load is the heating roller and no large variation exists in the inductance of the magnetic flux path, there is no big difference in the inductance between the loads formed either in a flat shape or in a roller shape. Also, when measuring the electric power transmission efficiency even with the measured frequency of 1 MHz, the electric power transmission efficiency was no more than 55%.
Further, the temperature rise time of the secondary coil in a core-less transformer coupling has been measured by an experimental test shown in FIG. 6 .
FIG. 6 is a schematic view illustrating a measuring system for the temperature rise of the secondary coil in the induction heating unit according to the present invention.
In FIG. 6 , a reference symbol HFG designates a high frequency electric power supply, a reference symbol MC designates a matching circuit, a reference symbol wp designates a primary coil and a reference symbol ws designates a secondary coil.
The high frequency electric power supply HFG produces a high frequency of 13.56 MHz.
The primary coil wp is composed of an aluminum wire in two turns and has a primary inductance of 170 nH.
The secondary coil ws is composed of a coil in one turn formed in a ring shape with a width of 10 mm, a thickness of 0.3 mm and a diameter of 20 mm. In this connection, the secondary resistance value is not optimized.
With the condition given above, the time interval wherein the surface temperature of the secondary coil ws reaches 150° C. was measured with the measured result being plotted in FIG. 7 .
FIG. 7 is a graph illustrating the measured result of the temperature rise of the secondary coil of the induction coil unit according to the present invention.
In FIG. 7 , the axis of abscissa designates input electric power (W) and the axis of ordinates indicates a required time interval (second) for heating.
As now apparent from the graph of FIG. 7 , the heating time is shortened in substantially proportion to the input electric power and the temperature of the secondary coil is raised in a fairly short time period. As previously noted above, the optimization of the secondary resistance value improves the electric power transmission efficiency, with a resultant further decrease in the time period required for heating.
In summary, according to the present invention, the presence of the secondary coil, of the heating roller, which is coupled with the primary coil of the induction coil unit through the core-less transformer coupling with the secondary coil of the heating roller having the secondary resistance value that is nearly equal to the secondary reactance allows the electric power transmission efficiency from the induction coil unit to the heating roller to be highly improved, thereby enabling the heating roller to be effectively heated up in a shortened time period.
According to a second aspect of the present invention, in addition to the feature of the induction heating roller device of the first aspect of the present invention, the induction heating roller device further features the provision of a wire pair extending from the primary coil, and a capacitor connected to the wire pair in close proximity to the primary coil
An electric circuit having a load composed of the induction coil has a low power factor. Further, the electric power supply is required to have an increased capacity with an increase in the electric power to be supplied. With the electric power supply having a low capacity, although the electric power supply can be received in an internal space of the heating roller, it is a general practice for the electric power supply to be located outside the heating roller due to a specific relationship between the electric power to be supplied and the heating roller with its suitable axial length and its inner diameter designed in a practical use. Thus, it is required for the wire pair to be prepared for providing electrical connection between the induction coil unit and the electric power supply. And, due to a lowered power factor, electric current flowing through the wire pair relatively increases, causing heat to be generated in the wire pair and an electric power transmission efficiency o be lowered with a subsequent insulating deterioration. Further, the larger the electric current flowing through the wire pair, the larger will be noise radiating from the wire pair, with a resultant issue such as an increase in danger of adversely affecting peripheral units.
According to the present invention, the presence of the capacitor connected to the wire pair in close proximity to the primary coil as discussed above allows the power factor of the electric current flowing through the wire pair to be improved, thereby decreasing the amount of electric current flowing through the wire pair. Thus, the above issue is effectively addressed.
In case of the primary coil composed of the plurality of coil components separately connected to the wire pair in parallel to one another, a plurality of capacitors may be connected to the wire pair in parallel to the primary coil components, respectively, or a single piece of capacitor may be connected to the wire pair at a position of the electric power supply of the primary coil in the most proximity thereto, i.e. in the vicinity of the end of the heating roller. With such an arrangement, the capacitors are located in a relatively low temperature environment.
According to a third aspect of the present invention, in addition to the feature of the induction heating roller device of the second aspect of the present invention, the induction heating roller device further features that the primary coil includes a plurality of primary coil components separately distributed along the axis of the heating roller and connected between a pair of wires and that a plurality of capacitors are connected between the pair of wires in close proximity to the plurality of primary coil components in parallel to one another.
According to the present invention, in case of the induction coil unit composed of the plurality of primary components, since the plurality of capacitors are connected to the pair of wires in close proximity to the primary coil components, respectively, it is possible for the power factor of electric current flowing through the wire pair in close proximity to the primary coil components to be improved for thereby decreasing the amount of electric current.
According to an fourth aspect of the present invention, in addition to the feature of the induction heating roller device of the first aspect of the present invention, the induction heating roller device features the provision of a plastic resin layer covered over the outermost circumferential periphery of the heating roller.
The plastic resin layer serves to allow the surface temperature of the heating roller to be distributed to a level as uniform as possible. Further, the plastic resin layer serves to smooth the surface of the heating roller. As a consequence, the plastic resin layer is designed to have a thickness to achieve the functions previously discussed above. In this respect, if the plastic resin layer has an excessive thickness, the temperature rise in the surface of the layer of the heating roller is delayed, resulting in crack due to a difference in a thermal expansion coefficient. To address such an issue, the plastic resin layer must be selected to have a suitable value, preferably within a range between 0.5 to 5 mm.
Furthermore, the plastic resin layer may comprise a multi-layered structure. For example, the multi-layered structure may be comprised of the plural laminated layers of different plastic resins.
Moreover, the plastic resin layer may be comprised of heat resistance material that resists the temperature rise of the heating roller, such as fluorocarbon polymers, silicone resin or epoxy resin.
With such a structure of the present invention described above, the surface temperature of the heating roller is maintained at a level as uniform as possible, providing an ease of uniformly heating an object body to be heated. Furthermore, since the surface of the heating roller is smoothed, the heating roller is brought into contact with the object body in a uniform manner, rendering it easy to uniformly heat the object body.
According to a fifth aspect of the present invention, there is provide an induction heating roller device which comprises an induction coil unit having a primary coil, a hollow heating roller having a secondary coil coupled to the primary coil of said induction coil unit through a coreless transformer coupling and having a secondary resistance value substantially equal to a secondary reactance, said heating roller being rotatably supported, and a power supply including a high frequency inverter composed of switching elements including unipole elements for producing a high frequency output of a frequency of more than 1.1 MHz to energize the primary coil of said induction coil unit. The unipole elements include MOSFETs, respectively.
The electric power supply produces the output of high frequency of more than 1 MHz by which the primary coil of the induction coil unit is energized. The high frequency is generated with the high frequency inverter. The high frequency inverter has a circuit configuration which is not limited and may comprise a half-bridge type inverter and, more preferably, a series-resonance type inverter.
In summary, further, the electric power supply may have the high frequency inverter and, in addition thereto, an active filter such as a switching regulator connected to a direct current input of the high frequency inverter. In this case, a PWM control is performed in a switching regulator to control the input voltage of the high frequency direct current inverter for thereby controlling the output voltage of the high frequency. This results in an ease of variable temperature control of the heating roller or of maintaining the same at a fixed value. In order to fixedly maintain the temperature of the heating roller, further, it is arranged such that a temperature sensor may be incorporated in the heating roller or the induction coil unit for monitoring the temperature of the heating roller with a view to controlling the switching regulator or the high frequency inverter in a feedback loop. However, the direct current input of the high frequency inverter may be connected to a matching circuit for outputting pulsating direct current voltage.
Further, the high frequency inverter is comprised of the switching elements composed of unipole elements, respectively. The use of MOSFETs for the unipole elements enables the switching operation at a drain efficiency of more than 90% in the frequency range of the present invention.
The secondary coil of the heating roller may have a structure wherein the secondary coil is coupled with the primary coil of the induction coil unit through the core-less transformer coupling or through a cored transformer coupling. Also, in case of the core-less transformer coupling, the secondary coil may have the secondary resistance value which is nearly equal to the secondary reactance of the secondary coil.
Now, the operation of the induction heating roller device is described below in detail.
Energizing the primary coil at the high frequency with the high frequency inverter using the MOSFETs for producing the high frequency of more than 1.1 MHz at a high conversion efficiency enables Q of the core-less coil to be increased. As a result, the primary coil may have a reduced amount of loss, thereby improving the electric power transmission efficiency with respect to the heating roller to be highly improved. However, if the output frequency is less than 1.1 MHz, then, it becomes difficult to obtain an adequately large Q and, thus, the presence of output frequency less than 1 MHz is not suited. In other word, a preferable frequency range of the high frequency is selected to be 1.5 to 6 MHz. Further, a more preferable frequency range of the high frequency is selected to be 2 to 4 MHz. Such a frequency range is also effective in the example shown in FIG. 5 for minimizing the switching loss of the MOSFETs while obtaining a high conversion efficiency.
According to a sixth aspect of the present invention, there is provided an induction heating roller device which comprises an induction coil unit having a primary coil with a midpoint thereof being connected to the ground, a hollow heating roller having a secondary coil coupled to the primary coil of said induction coil unit through a coreless transformer coupling and composed of a closed circuit, said secondary coil having a secondary resistance value substantially equal to a secondary reactance, said heating roller being rotatably supported, an electric power supply for energizing the primary coil of said induction heating coil unit, and a smoothing circuit interposed between said induction coil unit and said power supply unit.
The primary coil of the induction coil unit is inserted through the heating roller and, hence, a self-loss is internally confined in the heating roller. As a result, since the surface temperature of the primary coil increases, the primary coil is liable to be overheated. When the primary coil reaches the high temperature, a heat cycle following the conducting or non-conducting states of the induction coil unit is applied to the primary coil. Since, in this instance, the primary coil generally has an increased electric current capacity, the primary coil is comprised of a large size raw wire which is mechanically formed into a desired configuration. If, in such a case, the primary coil is exposed to the heat cycle, a distortion that would occur during a coil forming period is released, causing deformation of the primary coil to obtain a given electric characteristic.
According to the present invention, since the smoothing circuit is interposed between the induction coil unit and the electric power supply, a midpoint of the primary coil of the induction coil unit can be connected to the ground. Connecting the midpoint of the primary coil to the ground enables the heat of the primary coil to be escaped through the midpoint earth connection path. As such, the temperature rise of the primary coil is limited, resulting in a capability of providing a well-balanced temperature distribution in the primary coil.
The secondary coil of the heating roller may have a structure wherein it is coupled with the primary coil of the induction coil unit through the core-less transformer coupling or through the cored transformer coupling. Also, in case of the core-less transformer coupling, the secondary coil may be so arranged as to have the secondary resistance value nearly equal to the secondary reactance of the secondary coil.
According to a seventh aspect of the present invention, in addition to the feature of the heating roller device of the sixth aspect of the present invention, the heating roller device includes a heat transfer path formed by a midpoint earth connection path of the primary coil at only one side of the heating roller.
According to the present invention, although the heat transfer path using the midpoint earth connection path of the primary coil is limitedly provided at one side of the heating roller to compel the primary coil to have a lower thermal conductivity than that obtained in the primary coil provided at its both ends with the heat transfer paths, it is possible for the temperature of the primary coil to be lowered while eliminating leakage current. Also, the presence of the heat transfer paths formed at both ends of the heating roller compels it to have two mounting locations, inviting a new issue of increased leakage current.
The secondary coil of the heating roller may have a structure wherein it is coupled with the primary coil of the induction coil unit through the core-less transformer coupling or through the cored transformer coupling. Also, in case of the core-less transformer coupling, the secondary coil may be so arranged as to have the secondary resistance value nearly equal to the secondary reactance of the secondary coil.
According to a eighth aspect of the present invention, there is provided a induction heating roller device which comprises an induction coil unit including a core made of a body and a flange integral with at least one end of the body, which are made of magnetic material, and a primary coil wound around an outer circumferential periphery of said body, and a hollow heating roller including a secondary coil formed in a closed circuit and having a plurality of component layers, which are laminated into a concentric relationship, whose at least one layer is made of an electrically conductive, magnetic material, to allow the inductive coil unit to be internally inserted for permitting the electrically conductive, magnetic material to be coupled to the primary coil of the induction coil unit through a transformer coupling, the secondary coil having a secondary resistance value substantially equal to a secondary reactance.
The core may include a single piece of core component or a plurality of core components formed along an axial direction of the heating coil. Even in case of the primary coil comprised of the single piece of coil component, the single primary coil may be comprised of divided windings formed on a plurality of core components or may be comprised of a plurality of primary coil components which are wound around the plurality of core components, respectively, on a one to one basis. Dividing the core along the axis of the heating roller into the plural core components enables the core to be manufactured at a low cost while enabling the magnetic fluxes of the cores of the inner primary coil from being leaked outside from respective magnetic flux paths.
Further, the core may include a body portion that has either a rod shape or a cylindrical shape. The flange portion of the core may be held in contact with the inner surface of the heating roller or a small gap may be formed between the flange portion and the inner surface of the heating roller to be held in non-contact relationship. With a structure wherein the inner surface of the heating roller is formed with an electrically conductive magnetic material and the flange portion of the core of the induction coil unit is held in contact with the inner surface of the heating roller to allow the heating roller to rotate, the magnetic reluctance is further reduced, thereby further increasing the coil efficiency. On the contrary, with the flange portion of the core held in non-contact with the inner surface of the heating roller, the rotation of the heating roller is not disturbed for minimizing the load of a drive motor which drives the heating roller while eliminating the wear of the heating roller, with a resultant decrease in manufacturing cost of a whole structure of the induction heating roller device while improving a reliability.
Furthermore, bearing mechanisms and drive mechanisms for the heating roller may be located along the axis of the heating roller at the sides thereof in areas outside the ends of the flange portions of the core. As a consequence, the bearing mechanisms etc. is located outside the magnetic flux path such that the magnetic flux path can not be adversely affected from the bearing mechanisms etc. to form an optimum magnetic path.
The heating roller may be comprised of a plurality of laminated sheets of thin electrically conductive magnetic material, or may be composed of a single piece of magnetic material. In addition to the electrically conductive material, the plastic resin layer may be formed over an outermost surface of the heating roller. Also, the electrically conductive magnetic material may be wound around a roller shaped base body made of electrically non-conductive material.
Moreover, the core of the induction coil unit is designed to have a length shorter than that of the axial length of the heating roller to allow the bearing mechanisms of the heating roller to be located to the ends of the heating roller. With such an arrangement, the heating roller is able to have the maximum effective length.
According to the present invention, the primary coil is wound around the outer periphery of the body portion made of magnetic material and the outer periphery of the body portion of the core having the flange portion, with the flange portion of the core being relatively located in close proximity to the secondary coil of the heating coil. Also, the presence of the secondary coil made of magnetic material allows the magnetic flux path to have a reduced magnetic reluctance. For this reason, a strong magnetic field may be internally formed in the magnetic flux path, enabling the primary coil of the induction coil unit to have an increased inductance.
Consequently, it is possible for a desired magnetic field to be formed with a relatively small amount of exciting current for thereby improving a coil efficiency.
According to a ninth aspect of the present invention, there is provided a heating roller for an induction heating roller device, said heating roller comprising a hollow roller base body made of electrically non-conductive material, and a plurality of secondary coil components composed of respective closed circuits circumferentially wound around said roller base body and distributed along an axis of said roller base body.
The roller base body is made of electrically non-conductive material such as ceramic, glass and other heat resisting plastic resin and has an internal hollow space. The hollow space is designed to have an adequate size to allow the induction coil unit to be internally received. Moreover, since the roller base body serves to take charge of a desired mechanical strength of the heating roller, the roller base body may be preferably designed to have a suitable thickness taking the strength of material forming the same into consideration.
The secondary coil may be formed either in one of the internal surface and the outer surface of the base body or in both the same. Further, the secondary coil may be formed of a single piece of secondary coil component or a plurality of secondary coil components. In addition, in case of the secondary coil composed of the plurality of secondary coil components, the plural secondary coil components may be located in a position to intersect the axis of the heating roller or in a plane to be slanted to the axis of the heating roller, i.e. in a condition to allow the axis of the heating roller and the axis of the secondary coil to intersect with respect to one another. With a structure in a latter case, the distance between the secondary coil components is shortened, with a resultant capability in uniformly heating the heating roller. Moreover, the presence of the secondary coil located in an overlapped relationship with the primary coil enables the coupling coefficient reduction to be limited to a relatively small value.
Further, the heating roller of the induction heating roller device according to the present invention may also be applied to the induction heating roller device discussed with reference to the first aspect and the eight aspect of the present invention.
Thus, in general, the base body made of electrically non-conductive material has a smaller thermal capacity than that made of metal such as iron, resulting in a reduced time period required for heating. Moreover, in case of fixed heat source, since the time period required for heating is determined by the product of the heat resistance and the heat capacity, the smaller the heat capacity, the shorter will be the time period required for heating. For example, in the related art practice, the heating roller includes the base body which is made of iron in the related art practice. In this connection, supposing that iron has a heat capacity of 100, soda glass and aluminum ceramic have the heat capacities of 58 and 87, respectively, either of which remains at a relatively small heat capacity level. Thus, the presence of the base body made of electrically non-conducting material enables the time period required for heating the heating roller to be shortened.
It will thus be appreciated that, according to the present invention, the induction heating roller device enabling the shortened warm-up heating time period can be obtained.
A heating roller of a tenth aspect of the present invention for the induction heating roller device of the ninth aspect of the present invention features that the secondary coil is located over an outer circumferential periphery of the roller base body.
The presence of the secondary coil formed over an outer periphery of the base body provides an ease of forming the secondary coil on the base body. That is, a desired secondary coil pattern can be formed with a plurality of secondary coil components which are electrically insulated from one another. Alternatively, the desired secondary coil can be made of a metallic foil which is stick to the base body.
Further, the heating roller for the induction heating roller device according to the present invention may be applied to the induction heating roller device of either one of the induction heating roller of the first to eight aspects of the present invention.
A heating roller of an eleventh aspect of the present invention for the induction heating roller device of the ninth or tenth aspects of the present invention features that each of a plurality of secondary coil components includes a coil component of a single turn.
Further, the heating roller for the induction heating roller device of the present invention may be applied to the induction heating roller device of either one of the first to eighth aspects of the present invention.
The presence of the secondary coil component made of single turn allows a periphery of the heating roller to be merely covered with a conductor with a suitable resistance which is formed in a ring shape, thereby making it possible to form a closed circuit of the secondary coil having a given secondary resistance value. In case of the secondary coil composed of the single piece of coil component having the single turn, the secondary coil is allowed to have a width covering a whole effective length of the heating roller along an axis thereof. Further, when forming the plurality of secondary coil components on the heating roller, it may be possible to select the number of secondary coil components, a width of each secondary coil component and a mounting pitch of the secondary coil component in respective suitable values such that the temperature of the heating roller is distributed along an axis thereof in a level as uniform as possible and the secondary coil has a desired secondary coil resistance value.
A heating roller of a twelfth aspect of the present invention for the induction heating roller device of the ninth aspect of the present invention features that a thermal conducting element extends across the plurality of secondary coil components and coupled thereto in thermally conductive relationship.
With such a structure according to the present invention, heat is transferred in dependence on the temperature gradient among the plurality of secondary coil components via the thermal conducting element extending across the plurality of secondary coil components. As a consequence, it is possible for uneven temperature distribution among the plurality of secondary coil components to be effectively eliminated.
The secondary coil may be comprised of single turn or more than single turn. In a latter case, if the thermal conducting element has a structure wherein it is thermally coupled to a plurality of points of the secondary coil of single turn, the thermal conducting element may be composed of electrically non-conductive material.
The thermal conducting element may be connected to a single point or a plurality of points of the periphery of the heating roller. Further, the width of the thermal conducting element may be formed in a smaller value than that of the secondary coil. With such a structure, it is possible for inductive current flowing through respective secondary coil components to be easily limited, thereby enabling leakage of electric current between the adjacent secondary coil components from being eliminated for providing an ease of design of the electric power transmission circuit between the primary and secondary coils.
Thus, the present invention enables uneven temperature distribution among the secondary coil components to be effectively eliminated, thereby eliminating uneven temperature distribution in the surface of the heating roller.
A heating roller of a thirteenth aspect of the present invention for the induction heating roller device of the twelfth aspect of the present invention features that the thermal conducting element includes an electrically conductive element.
The presence of the thermal conducting element made of electrically conductive element enables a decrease in an electric potential difference between adjacent points, of the plurality of secondary coil components, to which the electrically conductive element is connected. Consequently, since the reference electric potentials among the respective secondary coil components can be equalized, it becomes easy for a distribution capacity between the respective secondary coil components and the ground to be determined.
Further, the thermal conducting element can be formed with the same material as that of the secondary coil. As a result, the thermal conducting element can be fabricated in an easy manner.
Thus, the present invention makes it easy for the secondary electric current to flow through the respective secondary coils in an equal level, thereby enabling heat to uniformly develop in the respective secondary coil components.
Furthermore, the presence of the distribution capacity that is easy to be managed makes it possible for leakage current to be eliminated.
According to a fourteenth aspect of the present invention, there is provided a heating roller for an induction heating roller device, said heating roller comprising a hollow roller base body made of electrically insulating material, and a plurality of secondary coil components composed of respective closed circuits circumferentially wound over a whole surface of said roller base body along an axis of said roller base body.
The roller base body may be formed of a cylindrical body made of glass.
The secondary coil may be formed by an electrically conductive film formed over an entire surface of an inner wall of the base body. In summary however, the secondary coil may be formed on not only the inner wall of the base body but also the outer wall of the base body.
Thus, the present invention makes it possible to obtain the heating roller which is simple in construction.
A heating roller of a fifteenth aspect of the present invention for the induction heating roller device of the ninth aspect of the present invention features that the secondary coil components are formed by electrically conductive films, respectively.
The electrically conductive films may be formed in deposition of electrically conductive material, chemical adhesion, stick of an electrically conductive foil and a thick film structure of electrically conductive material.
In such a manner, the present invention enables the secondary coil to be thinned.
A fixing apparatus of a sixteenth aspect of the present invention features the provision of a fixing frame body including a pressure roller, and an induction heating roller device of the first aspect of the present invention wherein a heating roller is held in pressured contact with the pressure roller to allow record medium, which is adhered with toner image, to be transferred through the both rollers for thereby causing the toner image to be fixed to said record medium.
A fixing apparatus of a seventeenth aspect of the present invention features the provision of the ninth aspect of the present invention wherein a heating roller is held in pressured contact with the pressure roller to allow record medium, which is adhered with toner image, to be transferred through the both rollers for thereby causing the toner image to be fixed to said record medium.
In a description of the present invention, the “fixing frame body” refers to a remaining structural portion which is left after removing the heating roller of the inductive heating device or the inductive heating roller device from the fixing apparatus.
The pressure roller and the heating roller may be held in directly pressured contact with one another or may be held in indirectly pressured contact with one another via a transfer sheet. Also, the transfer sheet may have an endless or roll shape.
Thus, the present invention enables the record medium, which is formed with the toner image, to be transferred between the heating roller and the pressure roller to allow the toner image to be fixed onto the record medium.
An image forming apparatus of an eighteenth aspect of the present invention features the provision of an image forming frame body including an image forming unit for forming toner image on record medium, and a fixing unit mounted in the image forming frame body of the sixteenth aspect of the present invention for causing toner image to be fixed to record medium.
An image forming apparatus of a nineteenth aspect of the present invention features the provision of an image forming frame body including an image forming unit for forming toner image on record medium, and a fixing unit, of the seventeenth aspect of the present invention, mounted in the frame body for causing toner image to be fixed to record medium.
In a description of the present invention, the “image forming frame body” refers to a remaining portion of the image forming apparatus from which the fixing apparatus is removed. Also, the image forming unit is comprised of a structure for forming image onto the record medium responsive to image information in an indirect image forming system or a direct image forming system. Moreover, the “indirect image forming system” refers to a system wherein image is formed by a transfer technology.
The image forming apparatus involves an electrophotograph copying machine, a printer and a facsimile.
The record medium involves a transfer material sheet, a print sheet, an electro-facsimile sheet and an electrostatic record sheet, etc.
Thus, the present invention allows the induction heating roller device of the first aspect of the present invention or the induction heating roller device of the ninth aspect of the present invention to include the heating roller to provide the image forming apparatus which is able to shorten the warm-up time interval.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view illustrating an equivalent circuit for an induction heating roller device according to the present invention;
FIG. 2 is a graph showing the relationship between α and Q ca for each coupling coefficient for illustrating an operating principle of the induction heating roller device according to the present invention;
FIG. 3 is a schematic view illustrating a measuring system of a preliminary test for confirming the operating principle of the induction heating roller device according to the present invention;
FIG. 4 is a graph illustrating variations of inductance and the coupling coefficient in terms of a measured frequency of the primary coil during non-mounting of a load in the preliminary test for confirming the operating principle of the induction heating roller device according to the present invention;
FIG. 5 is a graph illustrating a variation of Q U of the primary coil during non-mounting of a load in the preliminary test for confirming the operating principle of the induction heating roller device according to the present invention;
FIG. 6 is a schematic view showing a measuring system for the temperature rise of a secondary coil of the induction heating device according to the present invention;
FIG. 7 is a graph showing a measured result of the temperature rise of the secondary coil of the induction heating device according to the present invention;
FIG. 8 is an exploded front view of the induction heating roller device, with partly in cross section, of a first preferred embodiment according to the present invention;
FIG. 9 is an enlarged cross sectional view of the induction heating roller device of the first preferred embodiment according to the present invention;
FIG. 10 is an enlarged, longitudinal cross sectional view illustrating an essential part of a heating roller shown in FIG. 9 ;
FIG. 11 is a circuit diagram illustrating an induction coil unit of a second preferred embodiment according to the present invention;
FIG. 12 is a circuit diagram illustrating an induction coil unit of a third preferred embodiment according to the present invention;
FIG. 13 is a circuit diagram illustrating an induction coil unit of a fourth preferred embodiment according to the present invention;
FIG. 14 is a conceptional graph illustrating a temperature distribution, together with a temperature distribution of a comparison example, which varies along an axis of the primary coil of the fourth preferred embodiment;
FIG. 15 is a circuit diagram illustrating an induction coil unit of a fifth preferred embodiment according to the present invention;
FIG. 16 is a front view, with partly cutaway, of a heating roller of an induction coil unit of a sixth preferred embodiment according to the present invention;
FIG. 17 is a front view of a heating roller of an induction coil unit of a seventh preferred embodiment according to the present invention;
FIG. 18 is a conceptional graph illustrating a temperature distribution, together with a temperature distribution of a comparison example, of the heating roller of thee induction coil unit of the seventh preferred embodiment according to the present invention;
FIG. 19 is an enlarged front view illustrating an essential view of an induction coil unit of an eighth preferred embodiment according to the present invention;
FIG. 20 is a longitudinal cross sectional view illustrating an induction coil unit of a ninth preferred embodiment according to the present invention;
FIG. 21 is a longitudinal cross sectional view illustrating an induction coil unit of a tenth preferred embodiment according to the present invention;
FIG. 22 is a longitudinal cross sectional view illustrating an induction coil unit of an eleventh preferred embodiment according to the present invention;
FIG. 23 is a longitudinal cross sectional view illustrating a fixing apparatus of a first preferred embodiment according to the present invention; and
FIG. 24 is a schematic cross sectional view illustrating a copying machine which serves as an image forming apparatus of a first preferred embodiment according to the present invention,
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
To describe the present invention more in detail, an induction heating roller device of a preferred embodiment according to the present invention will be described below in detail in conjunction with FIGS. 8 to 10 , wherein FIG. 8 is an exploded view, partly in cut away, of the induction heating roller device of a first preferred embodiment according to the present invention. FIG. 9 is an enlarged transverse cross sectional view of an induction heating roller. FIG. 10 is an enlarged longitudinal cross sectional view of an essential part of the heating roller shown in FIG. 9 .
In FIGS. 8 to 10 , like component parts bear the same reference numerals as those used in FIG. 3 and a detailed description of the same is herein omitted for the sake of simplicity. In the presently filed preferred embodiment, the induction coil unit device IC includes a primary coil composed of a plurality of primary coil components wp, and the heating roller TR includes a secondary coil composed of a plurality of secondary coil components ws, with the secondary coil components ws being formed on an outer circumferential wall of a base body BB.
In the induction heating coil device IC, the plural primary coil components wp are separately formed in a plurality of groups over an outer circumferential wall of a bobbin CB and connected to a wire pair WP in a parallel relationship with respect to one another.
The heating roller TR is comprised of a non-conductive roller base body BB, the plurality of secondary coil components ws, a glass sealing layer GS and a plastic resin layer PL. The non-conductive roller base body BB is comprised of a cylindrical body, which has an outer diameter of 30 mm and is made of aluminum ceramic material. Each of the plurality of secondary coil components ws is made of a thick film copper conductor with a width of 1 mm and is formed over the roller base body BB in a ring shape to form a single turn in a closed circuit. When the primary coil components wp are applied with a high frequency of 3 MHz, the secondary coil components ws have an inductance of 60 nH with a secondary resistance value R of 1.2 Ω. From this value, it is settled that the value of α=R a /X a equals about 1. The thick film copper conductors are formed by carrying out screen printing of paste-like conductive material, primarily made of copper, over the surface of the base body BB, drying the copper conductors and baking the dried conductors to obtain final products. The glass sealing layer GS is formed over the base body BB above the secondary coil components ws for sealing between the secondary coils ws and the base body BB. The plastic resin layer PL is made of fluorine plastic resin covered on the glass sealing member GS. It is to be noted here that the heating roller has bearing mechanisms, for rotation, of a related art structure, and a detailed description of the same is herein omitted.
FIG. 11 is a circuit diagram illustrating an induction coil unit of a second preferred embodiment according to the present invention.
In FIG. 11 , the circuitry includes a low frequency alternating current power supply AC, a high frequency alternating current power supply HFG, the induction coil unit IC and the heating roller TR.
The low frequency alternating current power supply is composed of a commercially available alternating current power supply of 100 volts.
The high frequency alternating current power supply HFG is comprised of a noise filter NF, a full-wave rectification circuit FRC, a smoothing capacitor C 1 and a half-bridge type high frequency inverter HF 1 . The noise filter NF serves to absorb high frequency noises that occur during switching operation of the high frequency inverter HF 1 for thereby avoiding the high frequency noises from flowing into the low frequency alternating current power supply SC. The full-wave rectification circuit FRC serves to rectify the low frequency alternating current into pulsating direct current to be output. The smoothing capacitor C 1 converts the pulsating direct current into smoothed direct current. The half-bridge type high frequency inverter HF 1 includes a pair of switching elements Q 1 , Q 2 , a pair of capacitors C 2 , C 3 and a series connected resonating circuit composed of an inductor L 1 and a capacitor C 4 . The pair of switching elements Q 1 , Q 2 are comprised of MOSFETs which are connected in series between both terminal ends of the smoothing capacitor C 1 . The smoothing capacitors C 2 , C 3 are connected to the switching elements Q 1 , Q 2 in parallel to one another. The inductor L 1 and the capacitor C 4 are connected to the terminal ends of the switching element Q 2 and load in series to form a series connected resonating circuit.
The induction coil device IC includes the primary coil components wp and the capacitor C 5 which are connected in parallel.
The heating roller TR includes the secondary coil components ws. Also, reference numeral R a designates an equivalent secondary resistance.
With such a high frequency inverter circuit HF 1 , an output frequency of 3 MHz appears at both terminals of the switching element Q 2 , causing the series connected resonating circuit composed of the inductor L 1 and the capacitor C 4 to apply the sine wave high frequency voltage of 3 MHz to the induction coil device IC. The presence of the induction coil device IC composed of the primary coil components wp and the capacitor C 5 connected thereto in parallel allows a power factor to be improved.
FIG. 12 is a circuit diagram of an induction coil unit of a third preferred embodiment according to the present invention.
In the third preferred embodiment, the induction coil unit is comprised of a plurality of primary coil components wp 1 , wp 2 , wp 3 , and a plurality of capacitors C 51 , C 52 , C 53 which are connected between the wire pair WP in the vicinities of the respective primary coils.
FIG. 13 is a circuit diagram of an induction coil unit of a fourth preferred embodiment according to the present invention.
In the fourth preferred embodiment, the induction coil device is comprised of a smoothing circuit MC which is connected between the high frequency power supply HFG and the induction coil device IC. The smoothing circuit MC is comprised of inductors L 2 , L 3 which are connected to the wire pair WP in series, and an inductor L 4 which is connected between a load side of the inductor L 2 and a terminal, at the high frequency power supply HFG, of the inductor L 3 to be magnetically coupled to the inductors L 2 , L 3 .
In the induction coil device IC, a middle point of the primary coil wp is connected to the ground.
FIG. 14 is a conceptional graph illustrating the relationship between the temperature distribution characteristic, varying along an axis of the primary coil forming part of the induction coil device of the fourth preferred embodiment, and the temperature distribution characteristic of comparison example.
In FIG. 14 , the abscissa axis indicates the position of the primary coil in an axial direction thereof, and the axis of ordinates indicates the temperature. The curve C is plotted for illustrating the temperature variation occurring in the present invention, and the curve D illustrates the temperature variation of the comparison example. Also, it is to be noted that the comparison example has the same specification as the circuit of the fourth preferred embodiment except for the mid point being connected to the ground.
As will be appreciated from the graph of FIG. 14 , the present invention compels the heat created in the mid point of the primary coil to be conducted outward to the ground through an earth connection path, with a resultant reduction in temperature that is relatively distributed in an equalized fashion.
FIG. 15 is a circuit diagram of an induction coil device of a fifth preferred embodiment according to the present invention.
The fifth preferred embodiment differs from the fourth preferred embodiment shown in FIG. 13 in that both the mid point of the primary coil wp and the one terminal, at the side of the high frequency power supply HFG, of the inductor L 3 connected to the wire pair WP are connected to the ground.
Induction coil devices of other preferred embodiments according to the present invention will now be described below with reference to FIGS. 16 to 22 , with like parts bearing the same reference numerals as those used in FIGS. 8 to 10 .
FIG. 16 is a front view of a heating roller TR of the induction coil device of the sixth preferred embodiment.
In the sixth preferred embodiment, the heating roller TR includes a secondary coil ws which is formed on the outer wall of the base body BB while compelling the axis of the secondary coil ws to intersect the axis of the heating roller TR. Also, the glass sealing layer and the plastic resin layer are herein omitted for the sake of simplicity.
FIG. 17 is a front view of a heating roller TR of the induction coil device of a seventh preferred embodiment according to the present invention.
In the seventh preferred embodiment, the heating roller TR includes a plurality of heat conductive elements TC extending over the plural secondary coils ws. Each of the thermal conductor elements TC is made of electrically non-conductive material and is formed over plural areas in the circumferential periphery of each secondary coil component ws. Also, the glass sealing layer and the plastic resin layer are herein omitted for the sake of simplicity.
FIG. 18 is a graph illustrating the relationship between the temperature distribution characteristic, varying along an axis of the heating roller forming part of the induction coil device of the seventh preferred embodiment, and the temperature distribution characteristic of comparison example.
In FIG. 18 , the abscissa axis indicates the position of the heating roller in an axial direction thereof, and the axis of ordinates indicates the temperature. The curve E shows the temperature variation occurring in the present invention, and the curve F illustrates the temperature variation of the comparison example. Also, it is to be noted that the comparison example has the same specification as the circuit of the seventh preferred embodiment except for the plural heat conductive elements.
As will be appreciated from the graph of FIG. 18 , the present invention allows the temperature distribution along the axis of the heating roller TR to be relatively equalized.
FIG. 19 is a partly cut out, front view of a heating roller TR of an induction coil unit of an eighth preferred embodiment according to the present invention.
In the eighth preferred embodiment, the heating roller TR includes a heat conductive element TC extending over the plural secondary coils ws. The thermal conductor element TC is made of electrically conductive material and is formed over plural areas in the circumferential periphery of each secondary coil component ws. Also, the glass sealing layer and the plastic resin layer are herein omitted for the sake of simplicity.
FIG. 20 is a longitudinal cross sectional view of an induction coil unit of a ninth preferred embodiment according to the present invention.
In the ninth preferred embodiment, the induction coil unit is comprised of a heating roller which includes a roller base body BB made of cylindrical glass, a secondary coil ws formed by electrically conductive film coated over an entire surface area along an effective length in an axial direction of an inner wall of the roller base body BB, and a plastic resin layer PL formed over an outer wall of the base body BB. Also, it is to be noted that the electrically conductive film is made of transparent ITO film.
FIG. 21 is a longitudinal cross sectional view of an induction coil unit of a tenth preferred embodiment according to the present invention.
In the tenth preferred embodiment, the induction coil unit IC is comprised of a core CO and a plurality of primary coil components wp formed thereon, with the secondary coil ws being composed of electrically conductive and magnetic material.
The core CO is made of ferrite and includes a cylindrical body CO 1 and flanges CO 2 integrally formed at both ends thereof. Each of the primary coil components wp is wound around the outer circumferential periphery of the cylindrical body CO 1 via a bobbin CB. The flanges CO 2 have outer circumferential peripheries located close proximity to an inner circumferential periphery of the secondary coil ws of the heating roller TR.
The heating roller TR includes the secondary coil which is comprised of a cylindrical body made of iron and which has an outer circumferential periphery coated with a plastic resin layer PL.
FIG. 22 is a longitudinal cross sectional view of an induction coil unit of an eleventh preferred embodiment according to the present invention.
In the eleventh preferred embodiment, the induction coil unit IC is formed into a plurality of divided component elements.
In particular, the core CO is comprised of a plurality of unit cores CO u each of which includes a cylindrical body CO 11 and a flange CO 12 integrally formed at one end of the cylindrical body CO 11 , with the plural unit cores CO u being connected together. In order to interconnect adjacent unit cores CO u , each unit core may have a suitable connecting segment. For example, a central area of an end wall of the flange CO 21 of the unit core CO u is formed with a threaded bore sb, and a central area of the other end of the unit core CO u is formed with an interconnecting element composed of an axially extending threaded portion. Screwing the threaded portion of one unit core CO u to the threaded bore sb of adjacent unit core CO u allows a desired number of unit cores CO u to be interconnected to one another. Also, the threaded portion formed at the left side of the unit core COu is screwed into the threaded bore formed at the central area of the flange CO 3 .
FIG. 23 is a longitudinal cross sectional view of a fixing apparatus of a first preferred embodiment according to the present invention.
As shown in FIG. 23 , the fixing apparatus of the present invention includes an induction heating roller 21 , a pressure roller 22 , record medium 23 , toner 24 and a frame body 25 , with other like parts bearing the same reference numerals as those used in FIG. 9 .
Any one of the induction heating rollers 21 shown in FIGS. 8 to 21 may be employed in the structure shown in FIG. 23 .
The pressure roller 22 is mounted in a pressured contact relationship with respect to the heating roller TR of the induction heating roller 21 , with record medium 23 being transferred between the both rollers in a pressured contact relationship.
Toner 24 is fixed to the surface of record medium 23 for thereby forming a desired image pattern.
The frame body 25 supports the various component parts, discussed above, (except for record medium 23 ) in a given positional relationship.
As such, the fixing apparatus allows record medium 23 , which is adhered with toner 24 to form the desired image pattern, to be interposed between and transferred between the heating roller TR of the induction heating roller 21 and the pressure roller 22 , and toner 24 to be applied with heat from the heating roller TR to be melt to carry out thermal fixing of toner 24 .
FIG. 24 is a schematic cross sectional view of a copying machine of a preferred embodiment serving as an image forming apparatus.
The image forming apparatus is shown including a reader unit 31 , an image forming unit 32 , a fixing unit 33 and a case 34 .
The reader unit 31 optically reads out image pattern of original sheet to produce an image signal indicative thereof.
The image forming unit 32 responds to the image signal for producing electrostatic charge of a latent image on a photosensitive drum 32 a , with toner being adhered to the electrostatic charge of the latent image to form reversed image pattern which in turn is transferred onto record medium, such as a paper sheet, to form a desired image pattern.
The fixing unit 33 has a structure shown in FIG. 23 for thermally melting toner, which is transferred to record medium, to cause toner to be thermally fixed thereto.
The case 34 conceals the various component parts discussed above involving the component parts 31 to 33 and includes a transfer unit, electric power supply and a control unit.
The entire content of a Japanese Patent Application No. P2001-016335 with a filing date of Jan. 24, 2001 is herein incorporated by reference.
Although the invention has been described above by reference to the preferred embodiments, the invention is not limited to the embodiment described above and other variations or modifications will occur to those skilled in the art, in light of the teachings. The scope of the invention is defined with reference to the following claims. | An induction heating roller, a fixing apparatus and an image forming apparatus are disclosed as including a heating roller (TR) comprised of a hollow roller base body (BB), composed of electrically insulating material, and a plurality of secondary coil components (ws), composed of closed circuits, respectively, which are formed over the roller base body. The heating roller (TR) internally receives an induction coil unit (IC) including a primary coil (wp) which is coupled with the secondary coils in a core-less transformer coupling relationship. The secondary coil components (ws) of the heating roller (TR) have a secondary resistance value (R a ) which is nearly equal to a secondary reactance (X a ), i.e. in case of R a /X a =α, a formula is expressed as 0.1<α<10. Further, the primary coil (wp) of the induction coil unit (IC) is comprised of a plurality of coil components which are connected between a wire pair (WP) in parallel to one another. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to thermal transfer printers, dyesheets therefor and methods of operation thereof.
SUMMARY OF THE INVENTION
[0002] According to one aspect of the invention there is provided a thermal transfer printer including detector means for detecting a light absorption characteristic of a thermal transfer dyesheet inserted in the printer, comparison means for comparing the detected light absorption characteristic with an acceptable light absorption characteristic and rejection means for preventing use or further use of the dyesheet in the printer if the detected light absorption characteristic fails to conform to the acceptable light absorption characteristic.
[0003] The detector means may be operative to detect the light absorption characteristic of one colour only of a multi-colour dyesheet, but to improve discrimination the detector means is preferably operative to detect the respective light absorption characteristics of more than one colour, the rejection means then preventing use or further use of the dyesheet if the detected light absorption characteristic of any one colour fails to conform to the acceptable light absorption characteristic for that colour. For each colour detected, the detector means preferably comprises a light source of a frequency appropriate to the colour to be detected and a detector which produces an electrical output signal representative of the attenuation of the light as a result of passage of the light through the colour of the dyesheet. The light source and detector may be on opposite sides of the plane of dyesheet movement through the printer or may be on the same side, the light then being transmitted a first time through the dyesheet, being reflected and then being transmitted a second time through the dyesheet. It is also possible to obtain further discrimination by measuring the light absorption characteristic of a black or overlay panel of the dyesheet.
[0004] Preferably, the detected light absorption characteristic is a magnitude of light absorption and the acceptable light absorption characteristic is a range of light absorption values, the rejection means then preventing use or further use of the dyesheet in the printer if the detected light absorption magnitude falls outside the acceptable range. It is convenient to quantify the absorption magnitude by taking the ratio of the detector output with the dye panel in place to the detector output on a clear portion of the dyesheet.
[0005] It is also possible for the light absorption characteristic to be the magnitude of optical density, where optical density has its conventional definition of log 10 (I 0 /I), in which I 0 is the intensity of the incident light and I is the intensity of the transmitted light.
[0006] The rejection means may operate in any one of a number of Ways. For example, the rejection means could prevent use or further use of the dyesheet by disabling an essential function of the printer such as dyesheet transport or operation of the print head, or the rejection means could eject the dyesheet from the printer, this being most practicable if the dyesheet is carried in a cassette or cartridge. In each case, the printer could produce an audible signal and/or a visual indication to the user that the dyesheet is not acceptable.
[0007] According to another aspect of the invention there is provided a method of determining the acceptability of a thermal transfer dyesheet in a thermal transfer printer, the method comprising determining a light absorption characteristic of the dyesheet, comparing the detected light absorption characteristic with an acceptable light absorption characteristic and preventing use or further use of the dyesheet in the printer if the detected light absorption characteristic fails to conform to the acceptable light absorption characteristic.
[0008] The light absorption characteristic may be determined by determining the intensity of light (of a chosen frequency) transmitted by a colour print panel of the dyesheet.
[0009] The dyesheet is normally fed from material wound up on a spool and is taken up after use on a second spool. In order to interrogate the successive panels of a dyesheet, it should desirably be wound past the detectors. Three possibilities are:
[0010] (i) After the dyesheet has been loaded into the printer, part of the installation procedure (eg closing the lid of the printer) triggers the detection process, which is carried out by winding forwards through a complete sequence, thus wasting one repeat unit of the dyesheet. This may not be of great consequence if there are several hundred repeats on the dyesheet spool. It does, however, mean that only a single check is made at the beginning, and subsequent panels could be out of specification.
[0011] (ii) After the dyesheet has been loaded, and at certain other times, the dyesheet is wound forwards to confirm its identity, and then wound back again, so that none is wasted. This would be a relatively slow process because of the need to wind the dyesheet in both directions.
[0012] (iii) Printing is carried out as normal, while simultaneously monitoring the light absorption of the dyesheet. If the dyesheet is inappropriate, the print cycle is aborted. This is potentially the simplest method to use, and in the event that the wrong dyesheet is used would limit wasted material to one unit of dyesheet and receiver.
[0013] Instead of interrogating colour print panels of the dyesheet, the intensity of light transmitted through a sample colour area on the dyesheet, corresponding to a colour print panel, may be determined in order to derive the light absorption characteristic. Preferably, these sample areas are interrogated by the printer before commencing printing, avoiding any additional winding or rewinding.
[0014] According to a yet further aspect of the invention there is provided a thermal transfer dyesheet for use in a thermal transfer printer, the dyesheet comprising colour print panels arranged in series along the length of the dyesheet, the colour print panels being arranged in repeating groups with each group comprising print panels of three different colours, between each group there being three sample colour areas spaced across the width of the dyesheet and corresponding in colour to the three colours of the print panels. The three different colours may be yellow, magenta and cyan, and there may also be a registration mark between each group of colour print panels.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention will now be further described, by way of example, with reference to the accompanying drawings, in which:
[0016] [0016]FIG. 1 shows part of a thermal transfer printer forming one embodiment of the invention,
[0017] [0017]FIG. 2 shows a part of the length of a dyesheet for use in the printer of FIG. 1,
[0018] [0018]FIG. 3 is a logic diagram showing operation of the printer of FIG. 1,
[0019] [0019]FIG. 4 shows part of a thermal transfer printer forming another embodiment of the invention,
[0020] [0020]FIG. 5 shows a part of the length of a dyesheet for use in the printer of FIG. 4, and
[0021] [0021]FIG. 6 shows an alternative logic diagram.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0022] Referring to FIG. 1, the printer has two spaced rollers 2 , 3 for guiding a dyesheet 1 in its passage from a supply reel 1 a to a take-up reel 1 b . The dyesheet 1 passes between a roller 5 and a thermal print head, not shown. In use, a receiver sheet 4 (e.g. paper or card) is positioned between the roller 5 and the dyesheet 1 to receive an image printed on the sheet 4 by activation of the print head which is in use pressed against the dyesheet 1 .
[0023] The printer also comprises detector means comprising three light sources in the form of light emitting diodes 7 , 8 , 9 emitting red, green and blue light, and respective detectors 10 , 11 , 12 mounted in a block 6 . The light emitting diodes 7 , 8 , 9 are positioned above the plane of transport of the dyesheet 1 through the printer, and the detectors 10 , 11 , 12 are positioned below the plane of transport of the dyesheet 1 . The three light emitting diodes 7 , 8 , 9 produce light having respective wavelengths of 620 an, 525 nm and 430 nm. The light emitting diodes 7 , 8 , 9 are spaced in a direction across the width of the dyesheet 1 , and each source 7 , 8 , 9 is positioned directly above a corresponding detector 10 , 11 , 12 .
[0024] A representative length of dyesheet 1 is shown in FIG. 2. The dyesheet 1 has colour print panels of yellow (Y) magenta (M) and cyan (C) arranged in series along the length of the dyesheet 1 . This group of three colour print panels repeats along the length of the dyesheet, and between each group there is a transverse registration mark 13 and three sample areas Y′, M′ and C′ spaced across the width of the dyesheet and corresponding to the yellow Y, magenta M and cyan C colour print panels. Thus, there are three sample colour areas which respectively correspond in colour and print density to the yellow magenta and cyan print panels of the dyesheet.
[0025] When the dyesheet 1 is located in the printer and transported to the appropriate position, red light from the source 7 passes through the sample area C′ and is detected by the detector 10 , so that the electrical output of the latter is representative of the extent of attenuation, and therefore light absorption, of the sample area C′ and thus of the print panel C. Similarly, green light from the source passes 8 through the sample area M′ and is detected by the detector 11 so that the electrical output from the latter is representative of the extent of attenuation, and therefore light absorption, of the sample area M′ and thus of the panel M. The same considerations apply to the source 9 , the detector 12 , the sample area Y′ and the print panel Y. Thus, the electrical signals from the three detectors 10 , 11 and 12 are representative of the light absorption values of the three colour print panels C, M and Y respectively.
[0026] [0026]FIG. 3 illustrates how the signals from the detectors 10 , 11 and 12 are processed in the printer. The magnitude of the signal from the detector 12 is used to compute the light absorption ratio of the yellow print panel Y, as indicated at 14 in FIG. 3. The light absorption ratio is the magnitude of light intensity transmitted through a colour print panel divided by light intensity transmitted through a clear area of the dyesheet. This light absorption ratio is fed to comparator means which are pre-programmed with an acceptable range of light absorption ratio, in this case 0.08 to 0.12 and preferably 0.09 to 0.11. In the comparator means, the detected light absorption ratio of the yellow print panel Y is compared (as indicated at 15 ) with the acceptable range. If the detected light absorption ratio of the Yellow print panel Y falls outside the acceptable range, the dyesheet is rejected, as indicated at 16 . If the light absorption ratio of the yellow print panel Y is acceptable, the method proceeds by measuring (at 17 ) the light absorption ratio of the magenta panel M, by reference to the signal from the detector 11 . In the comparison step 18 , the light absorption ratio of the magenta panel M is compared with the acceptable range of 0.04 to 0.08, and preferably 0.05 to 0.07. The dyesheet is rejected, as indicated at 19 if the detected light absorption ratio falls outside the acceptable range. If the light absorption ratio of the magenta panel M is within the acceptable range, the method proceeds (step 20 ) by measuring the light absorption ratio of the cyan panel C, by reference to the signal from the detector 10 . In the comparison step 22 the light absorption ratio of the cyan panel C is compared with the acceptable range of 0.015 to 0.04, preferably 0.022 to 0.034. If the dyesheet fails to conform, it is rejected, step 23 . This rejection may involve ejection from the printer of the cassette holding the supply reel 1 a and the take-up reel 1 b . If the light absorption ratio of the cyan panel C is within the acceptable range, the dyesheet is accepted (step 24 ), having then satisfied the criteria for absorption ratios of all three print panels. Printing by use of the accepted dyesheet can then proceed.
[0027] Those skilled in the art will recognise that the absorption ratios at the absorption maximum translate to higher values at wavelengths slightly removed from the maximum, and will depend on the broadness of the emission band of the light source. It may be desirable to use such other wavelengths, either because of the availability of a suitable light source, or in order to reduce the attenuation caused by the dyesheet. The important factor is to match the printer recognition pattern to the optical properties of dyesheets that are within the acceptable specification. It will also be recognised that, although light emitting diodes provide convenient narrow-band sources, they often produce a further output band in the infrared region of the spectrum. For this reason it is highly desirable to use a detector which is insensitive to the infrared, as otherwise the discrimination is lost. It will also be recognised that it may be convenient to use a single detector with multiple light sources directed towards it. The sources can be switched on in turn in order to provide a sequential interrogation of the different colours.
[0028] Alternatively, it is possible to employ a broadband light source with multiple wavelength-selective detectors.
[0029] In FIGS. 4 and 5, parts corresponding to those of FIGS. 1 and 2 bear the same reference numerals. The printer of FIG. 4 differs from the printer of FIG. 1 in that the printer of FIG. 4 is designed to detect light attenuation through the colour print panels of a dyesheet, not through sample colour areas. The printer of FIG. 4 has a composite light source 25 positioned above the plane of movement of the dyesheet 1 through the printer, and a single detector 26 positioned below the plane of movement of the dyesheet 1 , the detector 26 being aligned with the composite light source 25 so that the detector 26 detects light from the source 25 after attenuation as a consequence of passing through the dyesheet 1 .
[0030] The composite light source 25 has three individual light sources, respectively producing light having wavelengths of 620 nm, 525 nm and 430 nm corresponding to the colours produced by the three diodes 7 , 8 and 9 of FIG. 1. The detector 26 is sensitive to light at each of these three wavelengths. Alternatively, three individual detectors (like detectors 10 , 11 and 12 ) can be grouped in a single composite detector positioned below the plane of movement of the dyesheet 1 through the printer.
[0031] The printer of FIG. 4 assesses the acceptability of a conventional dyesheet, a portion of which is illustrated in FIG. 5. This dyesheet differs from the dyesheet shown in FIG. 2 in that it is devoid of the sample areas Y′, M′ and C′.
[0032] When the dyesheet 1 of FIG. 5 is inserted in the printer of FIG. 4, the dyesheet is initially advanced to a first index position at which the first yellow colour print panel Y is interposed between the composite source 25 and the detector 26 , so that the electrical signal from the detector 26 is representative of the light absorption value of the yellow colour print panel Y. The dyesheet 1 is then sequentially advanced to second and third index positions at which the first magenta colour print panel M and the first cyan colour print panels C are in turn interposed between the composite light source 25 and the detector 26 , so that the detector produces two further electrical signals respectively representative of the light absorption values of the colour print panels M and C.
[0033] The three signals from the detector 26 are subjected to processing in a logic sequence corresponding to the flow diagram of FIG. 3. The dyesheet 1 of FIG. 5 is thus accepted for printing if the light absorption values of all three colour print panels Y, M and C are acceptable. If not, the rejection means of the printer are operative to eject the dyesheet.
[0034] It will be appreciated that the printer of FIG. 1 could be used to assess the acceptability of a dyesheet 1 of the form shown in FIG. 5, but in this case the signals from the detectors would be produced in succession as the colour print panels Y., M and C are moved successively to their index positions.
EXAMPLE
[0035] Light was directed separately from each of three light emitting diodes (LED) towards a silicon photodiode with a built-in infrared cut-off filter (type VTB8440B, manufactured by EG&G). A voltage of 10.5 V was applied to the photodiode, which was connected in series with a 10 M Q resistor. The voltage across the resistor was recorded as a measure of the transmitted light intensity. The light absorption ratio was calculated by taking the ratio of the measured voltage with a panel of the corresponding colour in place to the measured voltage with a clear section of dyesheet in place.
[0036] Three different dyesheets were tested in this way:
Nomi- nal Dyesbeet 1 Dyesheet 2 Dyesheet 3 Wave- Light Light Light length/ Panel Absorption Absorption Absorption LED nm Colour Ratio Ratio Ratio Kingbright 620 Cyan 0.028 0.0085 0.001 L934SED RS 525 Magen- 0.061 0.035 0.002 249-8752 ta Kingbright 430 Yellow 0.098 0.161 0.051 L934MBD
[0037] All components were obtained from RS Components Ltd.
[0038] The acceptable ranges of light absorption ratios are 0.022 to 0.034 for cyan, 0.05 to 0.07 for magenta and 0.09 to 0.11 for yellow. Dyesheet 1 passed on all 3 panels, while dyesheets 2 and 3 failed. This example is applicable to the printer of FIG. 1 or to the printer of FIG. 4.
[0039] [0039]FIG. 6 represents a simpler method in which the light absorption of a single print panel is tested, the result being to accept or reject the dyesheet dependent on whether the detected light absorption is within or outside the acceptable range of light absorption pre-programmed into the printer.
[0040] The rejection of the dyesheet or ribbon prevents its use or fer use in the printer, so the user is obliged to replace the rejected dyesheet or ribbon by a fresh dyesheet or ribbon which is then subjected to detection of its light absorption, as described. | A thermal transfer printer includes three light emitting diodes ( 7, 8, 9 ) emitting red, green and blue light respectively, and respective detectors ( 10, 11, 12 ) mounted on the opposite side of a dyesheet ( 1 ) passing through the printer. The detectors ( 10, 11, 12 ) detect the light absorption ratios of three colour print panels (Y, M and C) of the dyesheet, and these detected ratios are compared C with acceptable ranges of light absorption ratios. If the detected light absorption ratio for any colour falls outside the corresponding range, use or further use of the dyesheet in the printer is prevented, for example by disabling an essential function of the printer or ejecting the dyesheet from the printer. | 1 |
TECHNICAL FIELD OF THE INVENTION
The present invention pertains in general to clock circuits and, more particularly, to a clock circuit with a fractional divide functionality to provide an output clock that is divided by a non-integer value.
CROSS REFERENCE TO RELATED APPLICATIONS
N/A
BACKGROUND OF THE INVENTION
In order to achieve a relatively high frequency operation for an integrated circuit, there will be provided on that integrated circuit clock circuitry. This clock circuitry will operate at some base reference frequency that is typically defined by a crystal time base. However, to obtain higher operating speeds, higher clock frequencies are required than are provided with the base timing circuitry. To facilitate this, clock multipliers are utilized. For example, there are situations where certain circuitry on the integrated circuit is not capable of operating at the integer multiplication factor. This is due to the fact that there is some component on a functional block on the circuit that, due to processing limitations, etc., do not allow the overall integrated circuit to function at the highest clock operating speed, although the clock portion of the integrated circuit can operate at that frequency. However, there may be a maximum operating speed or frequency at which the functional circuitry will operate that is not an integer multiplication factor of the base timing of the clock. Rather than redesign the multiplier circuit, the full multiplication of the clock is performed and then a fractional divide is made to that maximized clock frequency. For example, if a base timing clock circuit operated on a crystal and provided a 25 MHz base clock, which was then multiplied to 100 MHz by a 4× multiplier, it may be that the functional circuitry or processing circuitry associated with the rest of the integrated circuit can only operate at ⅔ of the 100 MHz operating frequency or 66.67 MHz. Therefore, a fractional divide circuit of ⅔ would be required.
SUMMARY OF THE INVENTION
The present invention disclosed and claimed herein, in one aspect thereof, comprises a fractional divide circuit for generating a periodic fractional clock. A base clock is provided for generating a pre-divide clock at a base clock frequency with a period counter provided for counting cycles of the base clock. A select register stores constants that define parameters for a fractional divide ratio, there being at least four. A positive edge flip flop is provided wherein two of the constants are associated therewith. A negative edge flip flop is provided wherein the other of the two constants are associated therewith. A matching device is operable for setting on the positive edge of the base clock the first flip flop when the first of the two associated constants matches the output of the period counter and clearing the first flip flop when the other of the two associated constants matches the output of the period counter, and setting on the negative edge of the base clock the second flip flop when the first of the two associated constants matches the output of the period counter and clearing the second flip flop when the other of the two associated constants matches the output of the period counter. The outputs of the second and first flip flops are ANDed to provide the fractional clock output.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying Drawings in which:
FIG. 1 illustrates an overall diagram view of an MCU with a separate low power real time clock (RTC);
FIG. 2 illustrates an overall block diagram of the MCU chip showing the various functional blocks thereof;
FIG. 3 illustrates a block diagram of the oscillators utilized for the processing operation of the MCU;
FIG. 4 illustrates a block diagram of the RTC;
FIG. 5 illustrates a logic diagram for the overall fractional clock circuit;
FIG. 6 illustrates a logic diagram for the period counter;
FIG. 7 illustrates a table depicting the state machine operation for determining load values for the period counter and the relationship to the positive edge and negative edge table;
FIG. 8 illustrates a flow chart for the operation of determining the load value from the value in the select register;
FIG. 9 illustrates a table for the counter values;
FIG. 10 illustrates a flow chart for the operation of the period counter;
FIG. 11 illustrates a table depicting the sequence of the counter as a function of the value in the select register; and
FIG. 12 illustrates a timing diagram for the operation of the clock logic diagram of FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1 , there is illustrated a block diagram of a processor-based system that drives the mixed signal technologies that include as a part thereof, a digital section including a central processing unit (CPU) 102 and a digital I/O section 104 that is operable to interface with various serial inputs and outputs. The system also includes the analog section which provides for an analog-to-digital converter (ADC) 106 that is operable to receive one or more analog inputs and also provides a digital-to-analog converter 110 for allowing digital information from the CPU 102 to be converted to analog output information. The operation of the CPU 102 is controlled by various clocks 112 in a primary oscillator section. These are the operational clocks that control the overall operation of the MCU. In one mode, they will be interfaced with a crystal 114 for precision operation thereof However, as will be described herein below, a precision internal non-crystal based clock can be utilized and, further, there can be a high frequency crystal and a low frequency crystal for two different operational modes. Normally, the output of the block 112 provides the operating clock with the CPU 102 .
There is also provided a separate stand alone real time clock (RTC) block 116 . This clock 116 operates on a separate RTC crystal 118 that provides the time base therefor. The RTC 116 interfaces with the chip supply voltage V DD , which also drives CPU 102 and the clock block 112 . The RTC block 116 interfaces with a battery terminal 120 and an external back-up battery 122 . The RTC 116 has disposed thereon a plurality of registers 124 , which are operable to store the timing information associated with the RTC 116 . The RTC 116 operates independently with the primary purpose being to maintain current time and date information therein separate and independent of the operation of the digital and analog sections and the power required thereby or provided thereto. This information can be initialized by the CPU 102 through a digital interface 130 with the registers 124 . During operation, the RTC 116 will update its internal time and date information, which information is stored in the registers 124 . The RTC 116 is operable to generate an interrupt on an interrupt line 132 (to the CPU 102 ). Therefore, the RTC 116 can interface with the CPU 102 in order to generate an interrupt thereto. As will be described herein below, this interrupt facilitates waking the CPU 102 up when it is placed into an inactive or deep sleep mode. However, the CPU 102 at any time can query the register 124 for information stored therein. The RTC 116 , as will also be described herein below, is a very low power circuit that draws very little current, the current on the order of 600 nA.
Referring now to FIG. 2 , there is illustrated a block diagram of the MCU 102 . As noted herein above, this is a conventional operation of, for example, a part number C8051F330/1 manufactured by Silicon Laboratories Inc. The MCU 102 includes in the center thereof a processing core 202 which is typically comprised of a conventional microprocessor of the type “8051.” The processing core 402 receives a clock signal on a line 204 from a multiplexer 206 . The multiplexer 206 is operable to select among multiple clocks. There is provided an 80 kHz internal oscillator 208 , a 24.5 MHz trimmable internal precision oscillator 212 or an external crystal controlled oscillator 210 . The precision internal oscillator 212 is described in U.S. patent application Ser. No. 10/244,344, entitled “PRECISION OSCILLATOR FOR AN ASYNCHRONOUS TRANSMISSION SYSTEM,” filed Sep. 16, 2002, which is incorporated herein by reference. The processing core 202 is also operable to receive an external reset on terminal 213 or is operable to receive the reset signal from a power-on-reset block 214 , all of which provide a reset to processing core 202 . This will comprise one of the trigger operations. The processing core 202 has associated therewith a plurality of memory resources, those being either flash memory 216 , SRAM memory 218 or random access memory 220 . The processing core 202 interfaces with various digital circuitry through an on-board digital bus 222 which allows the processing core 202 to interface with various operating pins 226 that can interface external to the chip to receive digital values, output digital values, receive analog values or output analog values. Various digital I/O circuitry are provided, these being latch circuitry 230 , serial port interface circuitry, such as a UART 232 , an SPI circuit 234 or an SMBus interface circuit 236 . Three timers 238 are provided in addition to another latch circuit 240 . All of this circuitry 230 - 240 is interfacable to the output pins 226 through a crossbar device 242 , which is operable to configurably interface these devices with select ones of the outputs. The digital input/outputs can also be interfaced to a digital-to-analog converter 244 for allowing a digital output to be converted to an analog output, or to the digital output of an analog-to-digital converter 246 that receives analog input signals from an analog multiplexer 248 interfaced to a plurality of the input pins on the integrated circuit. The analog multiplexer 248 allows for multiple outputs to be sensed through the pins 226 such that the ADC can be interfaced to various sensors. Again, the MCU 102 is a conventional circuit.
Referring now to FIG. 3 , there is illustrated a schematic diagram of the primary oscillator section comprised of the oscillators 210 and 212 and the multiplexer 206 . The oscillator 210 is a crystal controlled oscillator that is interfaced through two external terminals 302 and 304 to an external crystal 306 and operates up to frequencies in excess of 25 MHz. A register 308 is provided, labeled OSCXCN, which is operable to drive control signals for the oscillator 210 and to record output values thereof. The output of the oscillator 210 is provided on a line 310 to one input of the multiplexer 206 (equivalent to multiplexer 142 in FIG. 1 ). The programmable precision trimmable oscillator 212 is controlled by a register 318 and a register 320 to control the operation thereof, i.e., to both set the frequency thereof and to enable this oscillator. The output of the oscillator 212 is processed through a divide circuit 330 , the divide ratio thereof set by bits in the register 320 to provide on an output 322 a precision high frequency clock to another input of the multiplexer 206 . The output of the multiplexer 206 is provided to the MCU 102 on the clock line 404 as a system clock signal SYSCLK. The clock select operation is facilitated with a register 324 labeled CLKSEL, which controls the multiplexer 206 .
The programmable high frequency oscillator 212 is the default clock for system operation after a system reset. The values in the register 318 , labeled OSCICL, provide bits that are typically programmed at the factory, these bits stored in the flash memory. The center frequency of the high frequency clock is 24.5 MHz. The divide circuit 330 can provide a divide ratio of one, two, four or eight. The oscillator 212 , in the C8051F330 device by way of example only, is a ±2 percent accuracy oscillator which has a center frequency that, although programmed at the factory, is allowed to be adjusted by changing the bits in the register 318 . There are provided seven bits in the register 318 that are calibratable bits. The register 320 provides an enable bit for the oscillator 212 and a bit that determines if the oscillator 212 is running at the programmed frequency. Two bits in the register 320 are utilized to set the divide ratio of the divider 330 .
There is also provided a clock multiplier circuit 350 , which is comprised of a multiplexer 352 for selecting the output of the clock circuits 210 , the internal clock 212 or the clock 210 divided by a factor of 2 and providing the selected clock to a 4× multiplier 378 . This multiplied clock is then input to a fractional divide block 380 , the output thereof selected by the multiplexer 206 . This block 350 is controlled by a select register 360 . The select register operates in accordance with the following table:
TABLE 1
CLKMUL: Clock Multiplier Control Register
R/W
R/W
R
R/W
R/W
R/W
R/W
R/W
MULEN
MULINIT
MULRDY
MULDIV
MULSEL
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
Bit 7 : MULEN: Clock Multiplier Enable
0: Clock Multiplier disabled. 1: Clock Multiplier enabled.
Bit 6 : MULINIT: Clock Multiplier Initialize
This bit should be a ‘0’ when the Clock Multiplier is enabled. Once enabled, writing a ‘1’ to this bit will initialize the Clock Multiplier. The MULRDY bit reads ‘1’ when the Clock Multiplier is stabilized.
Bit 5 : MULRDY: Clock Multiplier Ready
This read-only bit indicates the status of the Clock Multiplier. 0: Clock Multiplier not ready. 1: Clock Multiplier ready (locked).
Bits 4 - 2 : MULDIV: Clock Multiplier Output Scaling Factor
These bits scale the Clock Multiplier output. 000: Clock Multiplier Output scaled by a factor of 1. 001: Clock Multiplier Output scaled by a factor of 1. 010: Clock Multiplier Output scaled by a factor of 1. 011: Clock Multiplier Output scaled by a factor of ⅔. 100: Clock Multiplier Output scaled by a factor of 2/4 (or ½). 101: Clock Multiplier Output scaled by a factor of ⅖. 110: Clock Multiplier Output scaled by a factor of 2/6 (or ⅓). 111: Clock Multiplier Output scaled by a factor of 2/7.
Bits 1 - 0 : MULSEL: Clock Multiplier Input Select
These bits select the clock supplied to the Clock Multiplier.
Clock Multiplier Output MULSEL Selected Input Clock for MULDIV = 000b 0 Internal Oscillator/2 Internal Oscillator × 2 1 External Oscillator External Oscillator × 4 10 External Oscillator/2 External Oscillator × 2 11 Internal Oscillator Internal Oscillator × 4
It can be seen that bits 4 - 2 set the divide ratio for the fractional divide circuit. For values “000,” “001” and “010,” there will be no fractional divide. For the remaining values, there will be a non integer divide.
Referring now to FIG. 4 , there is illustrated a detailed block diagram of the low power RTC 116 . There is provided a dedicated RTC oscillator 402 that is operable at 32 kHz oscillator frequency, which can be utilized with or without a crystal. There are provided two external pads 404 and 406 for interfacing with the crystal in a crystal-based mode or they can be connected together in a non-crystal based mode. Then the RTC 116 receives the back-up battery input on the node 120 and supply voltage V DD on a V DD pin 408 . A 48-bit timer 410 is provided which is clocked by the RTC oscillator 402 . An RTC state machine 412 controls the operation of the RTC 116 and is operable to interface with the 48-bit timer 410 to write data therein or read data therefrom and in general control the configuration thereof. As will be described herein below, the 48-bit timer includes a counter, latches and an alarm function. The RTC state machine 412 is operable to generate the interrupt on the line 132 , when necessary, and is interfaced with an RTC internal bus 414 . The internal bus 414 is operable to interface with a back-up RAM 416 , which is typically configured with static RAM (SRAM) with a storage capacity of 64 bytes. Storage is provided by internal registers 418 which provide an internal storage for the data captured from the 48-bit timer 410 and various addressing data that is transferred between the RTC state machine 412 and the CPU 102 . There is provided an interface register 420 that allows the CPU 102 an interface path to the internal registers 418 . There is provided power control with a switch over logic block 424 , which is operable to monitor the voltage level of V DD and, if it falls below a predetermined level, it will switch over to a back-up battery on the input terminal 120 (noting that the voltage V DD can be provided by a primary battery). There is provided a regulator circuit 428 that regulates the bach-up battery or the supply voltage to the appropriate level, if necessary.
When utilized with a crystal, operating at a frequency of 32.768 kHz watch crystal and a back-up power supply of at least 1V, the RTC 116 allows a maximum of 437 years of time keeping capability with 47-bit operation or 272 years with 48-bit resolution. This is independent of the operation of the overall MCU. Although not shown, the RTC state machine 412 also includes a missing clock detector that can interrupt the processor and the oscillators 118 from the suspend mode, or even generate a device reset when the alarm reaches a predetermined value.
The interface registers 420 include three registers, RTC0KEY, RTC0ADR, and RTC0DAT. These interface registers occupy a portion of the special function register (SFR) memory map of the CPU 102 and provide access to the internal registers 418 of the RTC 116 . The operation of these internal registers is listed in the following Table 2. The RTC internal registers 418 can only be accessed indirectly through the interface registers 420 .
TABLE 2
RTC0 Internal Registers
RTC
RTC
Address
Register
Register Name
Description
0x00-
CAPTUREn
RTC Capture Registers
Six Registers used for
0x05
setting the 48-bit RTC
timer or reading is
current value.
0x06
RTC0CN
RTC Control
Controls the operation of
Register
the RTC State Machine.
0x07
RTC0XCN
RTC Oscillator
Controls the operation of
Control Register
the RTC Oscillator.
0x08-
ALARMn
RTC Alarm Registers
Six registers used to set
0x0D
the 48-bit RTC
alarm value.
0x0E
RAMADDR
RTC Backup RAM
Used as an index to the
Indirect Address
64 byte RTC backup
Register
RAM.
0x0F
RAMDATA
RTC Backup RAM
Used to read or write the
Indirect Data Register
byte pointed to
by RAMADDR.
The RTC interface register RTC0KEY is a lock and key register that is operable to protect the interface 420 . This register must be written with the correct key codes, in sequence, by the CPU 102 before Writes and Reads to the internal address register RTC0ADR and the internal data register RTC0DAT of the internal registers 418 . This provides an address for the internal back-up RAM and data for being stored thereat for a Write and provides an address for a Read with a subsequent Write to the RTC0DAT register by the RTC 116 followed by a subsequent Read of that RTC0DAT register by the CPU 102 . The key codes are 0xa5, 0xf1. There are no timing restrictions, but the key codes must be written in order. If the key codes are written out of order, the wrong codes are written, or an invalid Read or Write is attempted, further Writes and Reads to RTC0ADR and RTC0DAT will be disabled until the next system reset. Reading of the RTC0KEY register at any time will provide to the interface status of the RTC 116 , but does not interfere with the sequence that is being written. The RTC0KEY register is an 8-bit register that provides four status conditions. The first is a block status, indicating that the two key codes must be sequentially written thereto. After the first key code is written, the status will change to the next status indicating that it is still locked, but that the first key code has been written and is waiting for the second key. The next status is wherein the interface is unlocked, since the first and second key codes have been written in sequence. The fourth status indicates that the interface is disabled until the next system reset. The RTC0KEY register is located at the SFR address 0xAE and, when writing thereto, the first key code 0xA 5 is written followed by the second key code 0xF1, which unlocks the RTC interface. When the state indicates that it is unlocked, then any Write to the RTC0KEY register will lock the RTC0 interface.
The RTC internal registers 418 can be read and written using the RTC0ADR and RTC0DAT interface registers. The RTC0ADR register selects the particular RTC internal register that will be targeted by subsequent Reads/Writes to RTC0DAT. Prior to each Read or Write, the RTC interface Busy bit, bit 7 therein, should be checked to make sure the RTC interface is not busy performing another Read or Write operation. An example of an RTC Write to an internal register would involve a Wait operation when the Busy bit indicates it is busy. Thereafter, the RTC0ADR bit would be written with the value of, for example, 0x06, which would correspond to an internal RTC address of 0x06. This will be followed by a Write of a value of, for example, 0x00 to RTC0DAT which will Write the value 0x00 to the RTC0CN internal register (associated with the internal 0x06 address), which RTC0CN register is the RTC control register. There are generally in this embodiment, sixteen 8-bit internal registers. There are six internal registers for the captured data from the timer 410 , one register for the RTC0CN control information, six alarm registers, and a back-up RAM address register and a back-up RAM data register. By first writing the control information to RTC0CN, this can be followed by writing or reading data from any of the other internal registers. To write to the register, the RTC0CN internal register has the Busy bit written thereto in order to initiate an indirect Read by the CPU 102 . Once the Read is performed by the CPU 102 , then the contents of RTC0DAT are loaded with the contents of RTC0CN. The system can be set such that there will be a sequence of indirect Reads by setting the appropriate bit in the control register. These will be provided with a series of consecutive Reads such that, for example, the contents of either the capture registers or the alarm registers can be completely read out. The RTC0ADR register will automatically increment after each Read or Write to a capture or alarm register. The RTC0CN register is an 8-bit register and has an enable bit, a missing clock detector enable bit, a clock fail flag bit, a timer run control bit indicating that the timer either holds its current value or increments every RTC clock period, an alarm enable bit that is operable to enable the alarm function, a set bit that causes the value in the timer registers, the capture registers, to be transferred to the RTC timer for initialization purposes and the capture bit that causes the contents of the 48-bit RTC timer to be transferred to the capture registers. There is also provided an oscillator control register, RTC0XCN, which is an 8-bit register providing for gain control of the crystal oscillator, a mode select bit for selecting whether the RTC will be used with or without a crystal, a bias control bit that will enable current doubling, a clock valid bit that indicates when the crystal oscillator is nearly stable and a V BAT indicator bit. When this is set, it indicates that the RTC is powered from the battery.
The RTC timer 410 is, as described herein above, a 48-bit counter that is incremented every RTC clock, when enabled for that mode. The timer has an alarm function associated therewith that can be set to generate an interrupt, reset the entire chip, or release the internal oscillator in block 112 from a suspend mode at a specific time. The internal value of the 48-bit timer can be preset by storing a set time and date value in the capture internal registers and then transferring this information to the timer 410 . The alarm function compares the 48-bit value in the timer on a real time basis to the value in the internal alarm registers. An alarm event will be triggered if the two values match. If the RTC interrupt is enabled, the CPU 102 will vector to the interrupt service routine when an alarm event occurs. If the RTC operation is enabled as a reset source, the MCU will be reset when an alarm event occurs. Also, the internal oscillator 112 will be awakened from suspend mode, if in that mode, on an RTC alarm event.
Referring now to FIG. 5 , there is illustrated a logic block diagram of the fractional divide circuit 380 , which is clocked by the pre-divide clock circuit. If the multiplier 378 was a 4× counter with a 25 MHz clock, then the pre-divide clock would have a frequency of 100 MHz. This is input on a node 502 . The select register 360 is operable to provide a 3-bit output value from “000” through “111.” As noted herein above, the first three values, “000,” “001” and “010” will select the pre-divide clock and the others will select fractional divide clocks. The select register output is utilized for the values of “011” and above to drive a period counter 504 . This will provide a count output on a line 506 . The period counter 504 is a state counter, wherein the load value of a counter is dependent upon the last state, on the output thereof. This will be described in more detail herein below. There are provided four constants, two for setting a positive edge flip-flop 508 and two for setting a negative edge flip-flop 510 . The two constants that are associated with the positive edge flip-flop 508 are the PE_LOW and PE_HIGH.
Each of the flip-flops 508 and 510 are clocked by the high frequency pre-divide clock on line 502 , it being noted that the flip-flop 510 is clocked with the inverted pre-divide clock. In order to determine what the data state is on the input to the flip-flop 508 , a state machine determines what the level of the clock is, i.e., “high” or “low,” the state of the clock relative to the two constants PE_LOW and PE_HIGH. For this portion of the state machine, the flip-flop 508 has a data input thereof connected to the output of an ordered multiplexer 514 . The multiplexer 514 has three inputs. The state machine operates such that the decision made with respect to the first input, if it is true, results in selection of that fixed input, a “1,” for output therefrom. If false, then the decision associated with the second input is assessed and, if true, then that fixed input, a “0,” is output as the input to the flip-flop 508 . If neither of the decisions for the first and second input is true, then the third input is connected to the Q-output of the flip-flop 508 . The first decision is a decision wherein the value of PE_HIGH associated with the particular 3-bit output of the select register 360 is compared to the count value of the period counter. Each of the potential 3-bit values above “010” stored in the select register 360 has associated therewith fixed values for PE_LOW, PE_HIGH, NE_LOW and NE_HIGH. If the corresponding value of PE_HIGH is determined to be equal to the output of the counter with an equality block 516 , then a “1” is input to the first input of multiplexer 514 , i.e., the highest priority one thereof. If the equality is not true, then the select input multiplexer 514 will evaluate the decision associated with the next input. The decision associated with the next input, the next priority input, will have a decision made as to whether the output of the counter 504 on line 506 is equal to the fixed value of PE_LOW associated with the of the select register 360 , decided in an equality block 518 . If so, a “0” is selected by the multiplexer 514 for output to the data input of the flip-flop 508 . If this is a false decision, then the output of the multiplexer 514 is connected to the output of the flip-flop 508 . Therefore, the multiplexer 514 will either force a “1” to the data input of the flip-flop 508 , a “0” or the last state, depending upon the comparison of the output value of the counter 504 with either PE_HIGH or PE_LOW. The Q-output of the flip-flop 508 is input to one input of an AND gate 520 .
The decisions made with respect to flip-flop 51 are similar to that associated with flip-flop block 508 . In this block, there is provided a multiplexer 524 that provides data to the data-input of the flip-flop 510 . The first input is associated with a decision wherein the constant NE_HIGH is compared with the output of a counter 504 and, if it is determined to be equal by an equality block 526 , then a “1” is output from the multiplexer 524 . If this is determined to be false, then the decision associated with the next input is determined. This is a decision wherein the fixed value of NE_LOW associated with the output of the select register 360 is compared to the output of the counter 504 with an equality block 528 and, if true, then a “0” on the second input of multiplexer 524 is connected to the output thereof. If neither decision associated with the equality block 526 or 528 were true, then the third input of the multiplexer 524 is connected to the Q-output of the flip-flop 510 such that the last state is forced as an input thereto. The Q-output of the flip-flop 510 is input to the other input of the AND gate 520 . The output of the AND gate 520 is input to one input of the multiplexer 532 , which is operable to select either the output of the AND gate 520 , this being the fractional divide clock, or select the pre-divide clock on the node 502 . The output of multiplexer 532 provides the clock output. The multiplexer 532 is operable to select the node 502 whenever the output of the select register 360 is either “000,” “001” or “010.” These three inputs are input to a 3-input OR gate 536 , the output thereof providing the select input to multiplexer 532 .
Referring now to FIG. 6 , there is illustrated a block diagram of the period counter 504 . The period counter 504 is a 3-bit counter that is comprised of a 3-bit state counter which has associated therewith three flip-flops 602 , 604 and 606 associated with the data output values, D 0 , D 1 and D 2 , respectively. These are provided on the Q-outputs thereof. The data inputs thereto are connected to the data input bits B 0 , B 1 and B 2 , respectively. The clock inputs of the flip-flops 602 - 606 are connected to the pre-divide clock on the line 502 .
The flip-flops 602 - 604 have the input state thereof determined by a state machine 610 , which is operable to perform a lookup and determine the data input value for the bits B 0 , B 1 and B 2 . This is either a predetermined state obtained from a lookup table or the last state thereof either decremented or incremented. The state machine 610 , as will be described herein below, has access to the contents of the select register 360 and also to a PE/NE table 614 .
Referring now to FIG. 7 , there is illustrated a table depicting the relationship between the value in the select register 360 , the initial counter load value and the PE/NE table 614 . The state machine 610 operates a counter by determining what the value in the select register 360 is and then determining what the initial load value is in order to determine the counter sequence. As noted herein above, for values in the select register 360 between 0-2, the period counter will not be required, since the output of the pre-divide clock is selected. However, once the value is equal to a value from 3-7, then the fractional divide will operate. There are provided two columns, one for the select register 360 output and one for the counter load value for the bits B 0 , B 1 and B 2 . In general, the counter load value is determined by examining the value of S 0 in the select register 360 and then, if it is a “1,” outputting the value of the select register as the values of B 0 , B 1 and B 2 , i.e., a direct correspondence therewith, or, if the value is a “0,” then shifting to the right by substituting B 0 with the S 1 value, B 1 with the S 2 value and B 2 with “0.”
The illustration of determining the counter load value is set forth in the flow chart of FIG. 8 . This is initiated at a block 802 and then flows to a decision block 804 to determine if the value of the select register is greater than or equal to “3.” If so, the program flows along the “Y” path to a decision block 806 to determine if the value of B 0 is equal to 1. If so, the program flows along the “Y” path to a function block 808 to set the load value equal to that in the select register 360 and then proceeds to an End block 810 . If the value of B 0 was determined not to be equal to “1” in the decision block 806 , the program flows along the “N” path to a function block 812 to make the substitution of B 0 to S 1 , B 1 to S 2 and B 2 to “0.” The program then flows to the End block 810 .
Referring now to FIG. 9 , the operation of the counter will be described. In general, the state machine 610 operates the counter as a decrementing counter. The initial load value, as determined by the flow chart of FIG. 8 will be loaded in to the counter. There will also be an overflow value, “OV,” that is associated with each value of the counter. The value of OV for count values of “2” through “7” will be set to “0.” For the value of “0” or “1” of the counter output, the overflow value is set to “1.” Once the counter is initialized at the load value, the counter will decrement until it is determined that the current state has an overflow value of “1” which will then result in the next value being the counter load value. In this embodiment, for a select register output of “011” associated with the value “3,” there will be a counter load value of “011.” This will result in the value of “011” being the initial value of the counter and then it will decrement to “010” with an overflow value of “0,” which will then result in the counter being further decremented to the value of “001.” The overflow value for “01” is “1,” such that the next state will be the counter load value of “011.” Thus, the counter will sequence from 3, 2, 1 over to 3, 2, 1, and so on. This, of course, is dependent upon the counter load value as set forth herein above with respect to the table in FIG. 7 .
Referring now to FIG. 10 , there is illustrated a flow chart depicting the operation of the period counter 504 . This is initiated at a block 1002 and then proceeds to a block 1004 to initialize the counter with a load to value. The initial value will be the load value form the table of FIG. 7 that his determined by the flow chart of FIG. 8 . This will be loaded as a load value in function block 1006 . The program then flows to a function block 1008 to clock this through to the output and then proceeds to a decision block 1010 to determine if the overflow value of the current state is “1.” If so, this indicates the end of the count and the program flows along the “Y” path back to the input of the function block 1006 to again load the load value determined by the flow chart of FIG. 8 . If the overflow value is not equal to “1,” then the program proceeds along the “N” path to a function block 1012 in order to decrement the output value by “1” and then provide this as the load value, i.e., this is a decremented counter. The program then flows back to the input of function block 1008 to again clock through the value to continue the count.
Referring now to FIG. 11 , there is illustrated a table depicting the counter sequence for a given value of the select register. As noted herein above, until the value equals “011” associated with the value of “3,” there will be no sequencing of the counter. For the value of “011,” the sequence will then be “321321. . .” for the remaining values of “4” through “7” there are illustrated the sequence of values that are output, each of these output values represented by a 3-bit count output. This is the output of the flip-flops 602 , 604 and 606 .
Referring now to FIG. 12 , there is illustrated a timing diagram depicting the operation of the embodiment of FIG. 5 . The pre-divide clock which is labeled CLKOUT PREDIV is set forth and the example herein will be that for the select register value of “011” which will have a sequence of “321321321321. . .” To evaluate this, it can be seen from the table of FIG. 7 that PE_HIGH is a “1” and PE_LOW is a “2,” NE_HIGH is a “2” and NE_LOW is a “3.” These are fixed values, i.e., the “constants,” for that select register value. For simplicity sake, there are provided four states for the results of the equality blocks 516 , 518 , 526 and 528 , associated with the constants PE_HIGH, PE_LOW, NE_HIGH and NE_LOW respectively. These are labeled fph, fpl, fnh and fnl, respectively. For the equality block 516 , the output will be true, i.e., “high,” for the situation where the count value is equal to the value of PE_HIGH of“1.” This will occur when the count value is equal to “1” and will be clocked by an edge 1202 of the high speed clock to provide a true result 1204 represented by a high state. The states for fph, fpl, fnh and fnl are a “0” for a false and a “1” for a true. Similarly, whenever the count value is “2,” fpl will be a true 1206 , indicated as occurring at edge 1208 of the high speed clock. The state of fnh will be a true 1210 at substantially the same time as fpl and fnl being a true 1212 whenever the count value is equal to “3.” This is periodic and, each time the count value is, for example, a “1,” then fph will be true, i.e., corresponding to the output of the equality block 516 .
On the output of the multiplexers 514 and 524 , there are provided a data input to the flip-flops 508 and 510 , respectively. These are referred to as the data states PE_DIV_D for the data on the positive edge and NE_DIV_D for the data to the input of the flip-flop 510 for the negative edge. For the positive edge, the multiplexer 514 first examines the first input to determine if the equality is true. If not, it will go to the next one. For the first count “3” and for the second count “2,” the decision is false and the second input will be evaluated. For the value of “3,” the equality associated with equality of block 518 is false and, therefore, the value will be that of the previous state. However, for a count value of “2,” the multiplexer 514 will select the “0” forced input for input to the input of the flip-flop 508 , such that a “low” will occur at a state 1214 . At the next clock, the counter output is a “1,” which results in the output of the equality block 516 being true and forcing a “1” to the input of flip-flop 508 , at a logic state 1216 . On the next clock cycle, the counter value is a “3,” resulting in the output of equality blocks 516 and 518 being false, such that the previous state is input to the data input flip-flop 508 . This state 1216 is clocked through to the output thereof, represented as a state 1218 . At the clock cycle 1220 , the equality blocks 516 and 518 are false and the output of the flip-flop 508 , being at a high state, will be loaded back into the multiplexer 514 to provide a state 1222 . At the next clock cycle, the counter value is “2” and the equality block 518 will have a true output, forcing a “0” to the input of the flip-flop 508 to provide a state 1224 .
The negative edge operation is also substantially the same. At the clock edge 1208 , the counter is decremented to the value of “2” that will result in the equality block 526 outputting a true determination and this will result in a “1” being forced to the input of the flip-flop 510 , as noted by a state 1228 . When a “1” is provided form the output of the period counter at the next clock cycle at edge 1202 , the output of both equality counters 526 and 528 will be false and the last state, the state 1228 , will be output at a state 1230 . At the next count value of “3” for the clock cycle 1220 , the output of the equality counter 528 is true and that will result in a “0” being forced to the input of the flip-flop 510 at a state 1232 .
The flip-flops 508 and 510 are clocked such that flip-flop 508 is clocked on the positive edge and flip-flop 510 is clocked on the negative edge. Therefore, the state of PE_DIV_D is clocked on the positive edge thereof and the state 1214 will be clocked through on the next rising edge 1202 to change the state to a state 1234 on the output of flip-flop 508 . The state 1228 on NE_DIV_D will be transferred to the output of flip-flop 510 on a negative edge 1236 to be transferred to the state 1228 to the output thereof at a state 1238 . Thereafter, the AND gate 520 will perform the AND function thereof to provide a clock output as set forth in the next diagram, this being a ⅔ clock in accordance with the operation thereof. It can be seen that over three clock periods from a negative edge 1236 to a negative edge 1240 of the master clock, there will be two clock cycles of the output clock. All of the tables and everything are designed to provide such.
Although the preferred embodiment has been described in detail, it should be understood that various changes, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims. | A fractional divide circuit for generating a periodic fractional clock is disclosed. A base clock is provided for generating a pre-divide clock at a base clock frequency with a period counter provided for counting cycles of the base clock. A select register stores constants that define parameters for a fractional divide ratio, there being at least four. A positive edge flip flop is provided wherein two of the constants are associated therewith. A negative edge flip flop is provided wherein the other of the two constants are associated therewith. A matching device is operable for setting on the positive edge of the base clock the first flip flop when the first of the two associated constants matches the output of the period counter and clearing the first flip flop when the other of the two associated constants matches the output of the period counter, and setting on the negative edge of the base clock the second flip flop when the first of the two associated constants matches the output of the period counter and clearing the second flip flop when the other of the two associated constants matches the output of the period counter. The outputs of the second and first flip flops are ANDed to provide the fractional clock output. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to tire mounting and dismounting devices and, more particularly, is directed towards apparatus for mounting and dismounting off-highway tires onto and off of their respective rims.
2. Description of the Prior Art
Tires and rims are maufactured in many different sizes for utilization with many different types of vehicles. The larger the size of the tire, the more difficult it becomes for a single individual to safely mount and dismount the tire to or from its associated rim.
For extremely large industrial tires, those which, for example, are mounted on 51 inch and larger rims, heavy expensive equipment and a multitude of personnel are required in order to safely complete a mounting or dismounting operation.
For those off-highway tires in the 15 to 25 inch diameter range, such as are commonly utilized for tractors, heavy trucks, construction vehicles, and mining vehicles, mounting and dismounting at on-site or remote areas must often be accomplished without the benefit of fancy equipment.
An exemplary technique for manually mounting such tires is described in the Goodyear Off-Highway Rims catalog No. TR71-6056R, at page 65. In the technique therein described, the tire is initially placed about the rim base while lying on its side. The side flange is then placed over the rim base and is manually pushed straight down as far as possible. The instructions then require the installer to actually stand on the side flange to force it below both grooves in the rim base. With the side flange and the installer thus positioned, the snap lock ring must then be manually inserted into the outer lock ring groove in the rim base. After the snap lock ring is in place in the case of tubeless tires (no easy task), a rubber sealing ring must then be placed in the lower sealing ring groove, an operation which also requires the flange to be held down below the groove exposure by having the installer stand on the tire's sidewall and/or flange. After ensuring, insofar as possible, that the lock ring fits snugly against the rim base around the entire circumference of the rim, the tire is then inflated by the installer. Upon inflation, the side flange will rise over the sealing ring and out against the lock ring.
The Goodyear catalog cautions that the lock ring must be properly seated before the tire is inflated. Otherwise, upon inflation, the lock ring may snap loose off the rim, and may cause serious injury, even death, to the installer. From this point of view, the manual procedure leaves much to be desired in terms of the degree of safety afforded to the installer. Many serious accidents have occurred as a result of inadvertent improper seating of the lock ring prior to inflation.
Further, when one attempts to follow such instructions to manually mount tires in the 24 to 25 inch diameter catagory, which are common on many large pieces of earth moving machinery, one generally faces many strenuous hours of back breaking labor in attempting to manually hold down the side flange and side wall of the tire while installing the split lock ring and sealing ring. It often requires two and perhaps three individuals to facilitate installation.
There are, unfortunately, no tools presently available which permit one person to more safely and easily mount such large off-highway tires.
Although it is common, in fact it is necessary, when mounting extremely large (51 inch diameter and larger) tires to employ large pieces of hydraulic equipment (as described on pages 70 and 71 of said Goodyear catalog), use of such equipment and personnel is highly impractical in remote locations where one frequently finds the necessity for mounting and/or dismounting the intermediate, but nevertheless large, sized tires (15 to 25 inches in diameter). It is simply too impractical and costly to ship such tires and rims back to a central garage or tire handling facility where the large equipment might be available.
It may therefore be appreciated that a great need exists for a versatile and safe tool which permits a single individual to on-site mount and dismount large diameter off-highway tires onto and off of their associated rims.
Prior art United States patents which illustrate exemplary tire handling devices in this general art area of which I am aware include: U.S. Pat. Nos. 1,530,265; 2,960,153; 3,574,318; 3,743,000; 3,857,431; and 3,942,575. However, none of the devices described in the cited patents come close to suggesting the invention concept to be detailed hereinbelow.
OBJECTS AND SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to provide an apparatus which permits a single individual to mount and dismount large, off-highway tires onto and off of their associated rims which overcomes all of the disadvantages noted above with respect to prior art techniques.
Another object of the present invention is to provide apparatus for mounting and dismounting large off-highway tires which may be safely utilized by a single individual, and which is simple in construction and is therefore durable and amenable to inexpensive manufacture and production.
A further object of the present invention is to provide apparatus for mounting and dismounting large, off-highway tires which is extremely versatile in enabling a wide range of tire and rim sizes to be accommodated.
A still further object of the present invention is to provide a novel and unique apparatus for permitting one person to mount large off-highway tires onto their associated rims in a manner which minimizes the risks of injury while still permitting simple, quick, and easy installation.
An additional object of the present invention is to provide apparatus which may be adapted for mounting or dismounting a large tire to or from its associated rim, which obviates the prior art necessity of requiring several individuals to unite in a back breaking manual effort in an attempt to properly seat the rim parts prior to inflation.
A still additional object of the present invention is to provide a large tire mounting device which is portable and therefore may be easily transported to and utilized in remote areas.
Another object of this invention is to provide an apparatus which is chiefly intended to facilitate the mounting of large tires to their rims, but which also may be utilized in a demounting procedure, and is especially useful in such demounting procedures where rust scale has accumulated on the rim parts to impede ordinary breaking down of the tire by conventional implements.
Another object of this invention is to provide a tool which may be constructed from conventional, readily available components, which is durable, has no moving parts, and which therefore will last indefinitely.
The foregoing and other ojbects are attained in accordance with one aspect of the present invention through provision of apparatus which may be adapted for mounting or dismounting a large tire to or from its associated rim, which comprises means for exerting pressure at two locations on the sidewall of the tire, and means for coupling the pressure exerting means to the tire rim. The two locations are preferably substantially diametrically opposed on the tire sidewall, the pressure exerting means preferably comprising two manually actuable hydraulic jacks. The coupling means more particularly comprises first means which extends between two opposed positions on the inner portion of the tire rims, second means extending across the two locations on the tire sidewall, and vertically oriented means for rigidly coupling the first and second means together.
In accordance with more specific aspects of the present invention, the first named means comprises a first rigid bar positioned transversely with respect to the vertically oriented means. The last-named means preferably includes means positioned near the lower end thereof for adjustably accommodating the height of the first rigid bar coupled thereto. The height adjusting means comprises a pair of substantially parallel downwardly depending flanges which have a plurality of spaced apertures formed therethrough for cooperating with a central aperture formed through the first rigid bar. A pin is provided for insertion through the central aperture and the selected apertures to rigidly connect the first bar with the vertically oriented means. A safety pin is also preferably provided which is inserted through a second set of apertures in the downwardly depending flanges, the second set of apertures being preferably located just below and adjacent to the apertures through which the first or primary pin has been inserted.
In accordance with other aspects of the present invention, means may be coupled to the ends of the first rigid bar for securing same to the inner periphery of the tire rim, the securing means comprising a pair of rigid hollow members which include means for fixedly securing same to the ends of the first rigid bar. In one embodiment, for use with a particular style of rim, each of the rigid hollow members has a wedge means which abuts the inner periphery of the rim, while in an alternative embodiment, each of the rigid hollow members includes means for clamping same to an inwardly extending flange on the rim.
In accordance with other aspects of the present invention, the second-named means comprises a second rigid bar which is also positioned transversely with respect to the vertically oriented means but across the top portion thereof. A height adjusting means is also provided at the top portion of the vertically oriented means, and preferably comprises a pair of substantially parallel upwardly extending flanges also having a plurality of spaced apertures formed therethrough. The second rigid bar includes a central aperture formed therethrough which is aligned with selected apertures in the upwardly extending flanges for coupling therewith via a primary coupling pin. A safety pin is also provided at the upper portion of the vertically oriented means for insertion through a second set of apertures which are preferably positioned just above and adjacent to those apertures through which the first or primary pin extends.
In accordance with other aspects of the present invention, the second rigid bar also includes means positioned at both ends thereof for operatively coupling same to the hydraulically actuable jacks which preferably include vertically extendible pistons. In a preferred embodiment, the operative coupling means comprises ring means positioned on the underside of the second bar for receivably retaining the upper ends of the pistons. Preferably, a plurality of rings are positioned at spaced corresponding locations on the ends of the second rigid bar whereby tires of a different diameter may be accommodated by the tool.
In accordance with still other aspects of the present invention, a pair of base plates may also be provided which are positioned respectively between the base of the two jacks and the two locations on the tire sidewall where the downward pressure is to be exerted. Each of the base plates preferably include an arcuate edge in juxtaposition to the rim flange for permitting selective engagement thereby during operation.
BRIEF DESCRIPTION OF THE DRAWINGS
Various objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description thereof when considered in connection with the accompanying drawings, in which:
FIG. 1 is a top view which illustrates a preferred embodiment of the present invention properly positioned with respect to a tire and rim which is to be mounted thereby;
FIG. 2 is a side view, partly in section, illustrating the various components of the preferred embodiment illustrated in FIG. 1;
FIG. 3 is an enlarged sectional view of a portion of the apparatus illustrated in FIG. 2 shown in one operative mode;
FIG. 4 is a view similar to that illustrated in FIG. 3 but showing an alternative mode of operation thereof;
FIG. 5 illustrates a preferred embodiment of the upper transverse jack-holding bar of the present invention;
FIGS. 6 and 7 respectively illustrate preferred embodiments of the right and left jack support members, respectively, of the present invention;
FIG. 8 is a perspective view of the main or center post assembly along wit associated components in accordance with the present invention;
FIG. 9 is a perspective view illustrating a preferred embodiment of the lower transverse bar of the present invention;
FIG. 10 is a perspective view illustrating yet another embodiment of a lower transverse bar in accordance with the teachings of the present invention;
FIG. 11 is a perspective view of a preferred embodiment of a rim-engaging member in accordance with the present invention;
FIG. 12 is a perspective view which illustrates an alternative rim-engaging member;
FIG. 13 is a perspective view illustrating an alternative component set up of the present invention, which is similar to the set up illustrated in FIGS. 1 through 4 but applied to a differently sized tire and rim;
FIG. 14 is a cross-sectional view of certain of the components illustrated in FIG. 13 and taken along line 14--14 thereof; and
FIG. 15 is a side view, partly in section, which illustrates yet another alternative component set up in accordance with the teachings of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, wherein like reference numerals represent identical or corresponding parts throughout the several views, and more particularly to FIGS. 5 through 12 thereof, there are illustrated in perspective views the main components which comprise a preferred embodiment of the present invention utilized for mounting and dismounting large, off-highway tires onto and off of their respective rims.
Referring first to FIG. 8, there is illustrated a perspective view of the main or center vertically oriented post which is indicated generally by reference numeral 10. The preferred construction of post 10 includes a solid central support portion 12 from which upwardly extends a pair of parallel flanges 14 which are intended to accommodate an upper transverse bar, as will become more clear hereinafter. The flanges 14 have formed therein a plurality of height adjusting apertures 16 at regular spaced locations. Preferably, ten such apertures are provided along the upper support flanges 14 as illustrated.
A primary or upper bar positioning pin 18 is connected to the main body portion 12 of center post 10 via a flexible chain 20. Chain 20 is connected between a ring or like member 24 on the end of pin 18 and a point of attachment 22 on body 12, which may comprise a weld joint. An upper safety pin 26 is also provided which preferably includes a ring handle 28 for easy manipulation thereof. Pins 18 and 26 are inserted through certain of the apertures 16 formed in flanges 14 in a manner which will be described in more detail hereinafter.
Extending downwardly from the solid central support portion 12 of center post 10 are a similar pair of parallel support flanges 30 having a plurality, preferably ten, of height-adjusting apertures 32 formed therethrough. A pimary lower bar positioning pin 34 is connected to body 12 via a chain 36 which extends between a weld point 38 and a ring 40 formed on the end of pin 34. A lower safety pin 42 may also be provided, pin 42 having a ring handle 44, or the like.
Referring now to FIG. 5, reference numeral 50 indicates generally a preferred embodiment of an upper transverse jack holding member. Jack holding member 50 comprises more particularly a rigid bar 52 having a central through aperture 54 which may be aligned upon installation with a pair of coaxial apertures 16 extending through flanges 14 of post 10 (FIG. 8). Bar 52 has formed on the lower surface thereof a plurality of pairs of jack support members in the form of rings 56, 58 and 62. Ring pairs 56, 58 and 62 are provided so as to accommodate tires of varying diameters in a manner to become more clear hereinafter.
Referring now to FIG. 9, another component of the preferred embodiment of the present invention is illustrated and comprises a lower transverse bar indicated generally by the reference numeral 60. Bar 60 comprises a rigid bar or rod 64 having a central through aperture 66 for mounting same to flanges 30. A small stabilizer pipe 68 is preferably welded to the upper surface of bar 60, pipe 68 having an aperture extending therethrough to assist in the assembly procedure of the present invention, to be described in more detail below. On the ends of bar 64 are provided inner and outer pairs of mounting apertures 72 and 74, respectively, which accommodate either the rim-engaging members 80 of FIG. 11 or the rim-engaging members 90 of FIG. 12, as the size and/or design of the particular rim may dictate. In a preferred construction, inner mounting apertures 72 are designed to be accommodated within a 24 inch diameter rim, while mounting aperture pairs 74 are utilized when the tool is assembled on a 25 inch diameter rim. The ends 76 of bar 60 are notched as indicated.
FIG. 10 indicates by reference numeral 70 an alternative construction of a lower transverse bar which may be utilized on smaller sized rims than the transverse bar 60 of FIG. 9. More particularly, the alternate construction 70 comprises a rigid rod 78 which is shorter in length than rod 64 of FIG. 9. Rod 78 includes a centrally formed through aperture 82 for mounting same to the apertures 32 formed in flanges 30 of post 10. At the respective sides of aperture 82 are formed another pair of apertures 84 to accommodate the rim engaging members 80 of FIG. 11. The lower transverse bar 70 is generally utilized in conjunction with rim diameters of 15 inches or so, as is illustrated in greater detail in FIGS. 13 and 14 to be explained hereinbelow.
Referring now to FIG. 11, reference numeral 80 indicates generally a first embodiment of a rim-engaging member. Member 80 is formed of a rectangular hollow body 86 forming a longitudinal slot 88 therethrough to permit mounting onto the ends of rods 60 or 70. Positioned in the side walls of rim-engaging member 80 are two pairs of mounting holes 92 and 94 for permitting adjustable mounting of member 80 on the inner and outer apertures 72 or 74 of bar 60, or the apertures 84 of bar 70. A mounting pin 96 is preferably permanently attached to member 80 via a flexible chain 98. The upper surface of body 86 includes on the right edge thereof a wedge 102 having an arcuate rim-engaging surface 104 formed thereon. It should be understood that while FIG. 11 illustrates only one rim-engaging member 80, a complementary, second member 80' (as illustrated in FIG. 2) is also provided with the apparatus of the present invention, complementary member 80' being a mirror image of rim-engaging member 80 illustrated in FIG. 11.
FIG. 12 illustrates another and alternative embodiment of a rim-engaging member 90 which is utilized in connection with tire rims having inwardly extending flanges, as is illustrated in FIG. 15, for example. Rim-engaging member 90 comprises a rectangular hollow body 106 which forms a longitudinal bar-mounting slot 108 therethrough. A vertical support post 112 extends from the upper surface of body 106, a horizontal supporting flange 114 extending from vertical post 112. Flange 114 has formed in the free end thereof a threaded clamping member 116 which has a rim-engaging cup 118 formed at the lower end thereof and a transversely positioned handle 122 for easy turning thereof positioned through its upper end. Finally, body 106 of member 90 includes a set screw 124 formed in a side wall thereof for securing same to one of the apertures 72 or 74 of bar 60. As with the above-described member 80, member 90 is provided in pairs, the complementary pair 90' being illustrated in FIG. 15.
FIGS. 6 and 7 illustrate a pair of right and left jack support members indicated generally by reference numerals 100 and 110, respectively. Jack support members 100 and 110 ae symmetrical with respect to one another in construction, and each include a substantially planar jack-supporting plate 126 upon which the bases of the hydraulic jack members are placed. Each plate 126 terminates in an arcuate edge 128 that approximates the curvature of the rim or rim flange adjacent to which the support members 100 and 110 are placed in use. Arcuate edges 128 are also formed by an increased thickness reinforced rim-engaging peripheral portion 132 which functions as a leveling means for the jacks, in a manner to become more clear hereinafter. Each plate 126 also includes a pair of apertures 125 formed at its corners.
Referring now to FIGS. 1 through 4, the utilization of the apparatus of the present invention will now be explained in conjunction with a conventional large diameter tire 120 which may, for example, be of a 24 inch diameter. Tire 120, shown in cross-section in FIGS. 2 through 4, includes an upper bead 134 and a lower bead 136. The rim assembly onto which the tire 120 is to be mounted comprises an annular rim base 138 having a lower bead seat 140 which terminates in a lower outwardly exending flange 142. Lower bead 136 of tire 120 fits in lower bead seat 140 as illustrated clearly in FIGS. 3 and 4.
The upper portion of rim base 138 terminates in a mounting bevel 148 which has a groove 152 formed about the outer periphery thereof for receiving a split lock ring 150, generally formed of spring steel, and illustrated in FIGS. 2 through 4 in its installed position. Connecting the rim base 138 and mounting bevel 148 is an inwardly extending tapered portion 160 (FIG. 3) which serves to seat the rim-engaging member 80 of FIG. 11 in the operational set up illustrated in FIG. 2, for example.
Provided about the mounting bevel 148 of the upper portion of rim base 138 is an upper tapered bead seat band 144 which terminates in an upper side flange 146. Finally, a sealing ring 154 is illustrated in its installed position between the upper bead seat band 144 and the rim 138.
The apparatus of the present invention is adapted for use in combination with a pair of hydraulic jacks 170 and 180 having respective handles 172 and 182 for manual actuation thereof. Jacks 170 and 180 each include a vertically actuable piston 174 and 184, respectively, extending upwardly from the top portions thereof. Pistons 174 and 184 mate with properly positioned jack support members 62 mounted on the underside of upper transverse jack holding member 50.
In operation, when it is desired to utilize the apparatus of the present invention to assist in the mounting of tire 120 onto its rim 138, first the particular diameter of the tire 120 and associated rim is determined and the appropriate lower transverse bar 60 or 70 is chosen. Assuming, for example, that tire 120 is a 24 inch diameter tire having the rim assembly construction indicated in FIGS. 2, 3 and 4, the longer lower transverse bar 60 of FIG. 9 will be selected. Further, since the rim assembly 138 of FIG. 2 has no center flange, the rim-engaging member 80 of FIG. 11 is selected for use, instead of the member 90 of FIG. 12.
After the deflated tire 120 has been placed about its rim base 138, and bead seat band 144 has been positioned between the upper bead 134 of tire 120 and rim base 138, jack support plates 100 and 110 are placed at substantially diametrically opposed positions on the peripheral sidewall of tire 120 as indicated clearly in FIG. 1, and jacks 170 and 180 are placed such that their bases 176 and 186 rest squarely upon jack support plates 100 and 110, respectively. Plates 100 amd 110 may be positioned either adjacent to or on top of bead seat band 144, as indicated respectively in FIGS. 3 and 4, as size and other considerations may dictate.
The rim-engaging members 80 and 80' are then fastened to the respective ends of bar 60 by inserting their pins 96 into their respective inner apertures 92 and 72 as illustrated. With bar 60 positioned within rim base 138, post 10 is placed in its vertical position such that flanges 30 encompass bar 60. The primary lower pin 34 is then positioned through the desired apertures 32 and 66 in flanges 30 and bar 60, respectively, to secure same together. The safety pin 42 is then inserted in the set of apertures immediately below those through which pin 34 has been inserted.
The upper horizontal transverse jack holding member 50 is then inserted between the upper flanges 14 of vertical post 10. Primary pin 18 is then inserted through aligned apertures 16 and 54 at the height at about which members 62 of bar 50 intercept the pistons 174 and 184 of jacks 170 and 180, respectively. Safety pin 26 is then inserted in the set of apertures immediately above that through which pin 18 has been inserted. This serves as an additional precaution to prevent upward movement of the assembly should pin 18 become dislodged.
With the set up illustrated in FIG. 2, the arcuate surface 104 of member 80 engages the inwardly tapered portion 160 of rim base 138 so as to form a solid wedge against upward movement of lower transverse bar 60. Rim-engaging member 80' is similarly wedged against portion 160 of rim 138 on the opposite end of bar 60 as illustrated.
When all of the components have been thus assembled, and it is desired to install the split lock ring 150 in its groove 152 formed in mounting bevel 148, it is necessary to exert an appreciable downward force on the respective plates 100 and 110 in order to compress the upper sidewall of the tire 120 in the fashion illustrated in FIG. 4. When pressure is applied to the plates 126, small portions of the adjacent tire sidewall will protrude into apertures 125 to act as slip-resistant means for the plates 100 and 110. Application of such a force at two diametrically opposed locations on the sidewall 135 of the tire 120 will act, I have found, to unformly lower the sidewall 135 of tire 120, as well as, if desired, flange 146 of bead seat band 144, in such a fashion so as to effortlessly by held below the groove 152 formed in mounting bevel 148 which permits relatively easy installation of split lock ring 150 if groove 152.
In order to compress sidewall 135 and/or bead seat band 144, the handles 172 and 182 of jacks 170 and 180 are substantially simultaneously actuated from the position shown in FIG. 2 so as to extend their pistons 174 and 184 upwardly. This, in turn, creates a downward force at the bases 176 and 178 of the jacks so as to compress the upper sidewall 135 in substantially the fashion illustrated in FIGS. 3 or 4. In FIG. 3, plate 100 is positioned such that all of the pressure exerted by base 176 is applied to the side wall 135 to force same downwardly, while in FIG. 4, the plate 126 is positioned in the reverse fashion to that illustrated in FIG. 3 so as to intercept the flange 146 of bead seat band 144 to force the latter downwardly along with the sidewall 135 of tire 120. This further facilitates the insertion of split lock ring 150 into groove 152.
The assembly of the present invention clearly provides safety features heretofore unavailable. With the set up illustrated in FIG. 2, even if the split lock ring 150 were to become unseated from its groove 152, as may occur, for example, during subsequent inflation of tire 120, transverse bar 50 would remain in place so as to act as a barrier against any upward travel of ring 150, whereby serious injury may be prevented. The apparatus of the present invention is preferably therefore left in place while the tire is being inflated, jacks 170 and 180 being released to permit the air pressure to inflate the tire. Furthermore, by having the jacks 170 and 180 diametrically opposed, and by having them apply substantially equal pressure onto the upper sidewall 135, the bead seat band 144 will be lowered substantially uniformly about the periphery of the rim so as to ensure uniform seating when the tire is inflated and to prevent binding. It is clear that a single individual may operate the device of the present invention to easily and safely install large, off-highway tires onto their associated rims without fear of injury and without requiring hours of manual back breaking labor previously found necessary.
Attention is now direction to FIG. 13, which illustrates a differently sized tire 200 which, for example, may comprise a 15 inch diameter tire. In this embodiment, the smaller lower transverse bar 70 is placed in vertical post 10 as illustrated. This particular rim assembly includes a rim flange 190 that extends inwardly from the rim base 192. As clearly illustrated in FIG. 14, the lower bar 70 need merely be placed underneath the inwardly extending flange 190 so as to provide the required upward resistance to the downward froces generated by jacks 170 and 180, without the need for either of the rim-engaging devices 80 or 90.
With reference to FIG. 15, reference numeral 250 indicates one of the larger 25 inch tires with which the present invention may be utilized. For this embodiment, due to the provision of an inwardly extending rim flange 196 from rim base 194, the clamp members 90 of FIG. 12 are utilized on the ends of lower transverse bar 60 illustrated in FIG. 9. After clamp members 90 and 90' have been mounted to bar 60, the assembly is then, in turn, mounted to the flange 196 and the clamping members 116 and 116' are tightened so as to support bar 60 thereacross. Vertical post 10 may then be placed in position as desired at the center of bar 60, and pin 42 may be placed through stabilizer pipe 68 or bar 60 until the primary pin 34 has been inserted through the proper apertures. The upper transverse bar 50 is then installed on vertical post 10 in the same manner as above described, and the remaining components may then be installed in the same general fashion as described above in connection with the embodiments illustrated in FIGS. 2 and 13.
It may be appreciated that the device of the present invention provides ease of handling and safety features heretofore unavailable. A single individual may safely and easily assemble and operate the apparatus to facilitate both the mounting and dismounting of a plurality of differently sized tires and rims. The invention is easy to operate, inexpensive, and obviates the need for complex machinery or power tools. It is very versatile and clearly finds application in the demounting process, especially in those cases where rust has accumulated between the bead seat band and the rim flange so as to require uniform large pressures for breaking down the tire. However, it should be understood that the primary use of the present invention is presently envisioned as a mounting assist tool.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | Apparatus which permits one individual to mount and dismount large, off-highway tires onto and off of their respective rims. The present invention is particularly designed to facilitate the mounting of such tires in a more safe, efficient, and far less laborious manner than heretofore possible. This is accomplished by the provision of apparatus which exerts great pressure on the sidewall of the tire being mounted so as to uniformly depress same to enable easy insertion of the lock ring about the tire rim. A preferred embodiment includes a pair of hydraulically operated jacks for exerting the pressure, and a rigid bar linkage interconnecting the moveable pistons of the jacks with the rigid rim structure to provide relative movement between the tire and the rim. The rigid bar linkages preferably includes means which allow the apparatus to be adapted to a plurality of differently sized tires and rims. | 1 |
FIELD OF THE INVENTION
This invention relates to write-read optical storage memory systems, and more particularly, to write once read many (WORM) memory systems having long retention life using an amorphous material such as diamond-like carbon, as the storage medium.
BACKGROUND OF THE INVENTION
The usual optical techniques for recording information on storage media is done by ablation of thin films with a focused laser beam. The thin film storage media using laser ablation may have very complicated structures, have low signal-to-noise ratios, require large amounts of laser energy, and suffer from degradation with time. Other optical techniques involve pit formation or bubbles in the thin film and in general require a surface deformation on the thin film to modify the optical properties of the active medium. One feature in common with all optical storage systems is the fact that optical storage systems utilize diffraction limited optics which is approximated by the wavelength of the laser light used to modify the material and to read the stored information from the storage media. As the wavelength of the laser light decreases, the optical spot size gets smaller, thus leading to higher bit density optical storage systems.
In U.S. Pat. No. 5,024,927 which issued on Jun. 18, 1991 to K. Yamada et al., an information recording medium capable of recording and erasing information with the application of electro-magnetic waves is described comprising a recording layer formed on a substrate, the recording layer including a carbon-based material, a polymer prepared by subjecting a pigment to plasma polymerization and an optically reversible material whose optical characteristics can be reversibly changed. The optically reversible material may be finally-divided particles of a metal dispersed in the carbon-based material. The carbon-based material serves as the matrix for the optically reversible material in the recording layer. Specific examples of the optically-reversible materials include chalcogens such as Te and Se, alloys of chalcogens, materials whose crystalline phase is optically changeable, such as Zn-Ag and Cu-Al-Ni, Phthalocyanine-type pigments whose crystalline phase is optically changeable, and organic chalcogen compounds prepared by plasma CVD, such as diphenyl tellurium, diphenyl selenium, dimethyl tellrurium, dimethyl selenium, tellurium diisopropoxy diacetylacetonate and selenium diisopropoxy diacetylacetonate.
In U.S. Pat. No. 4,812,385 which issued on Mar. 14, 1989 to K. C. Pan, a write once read many (WORM) optical memory system is described. A recording laser provides a laser beam through a series of lenses to be focussed as a spot on a rotating disk. The disk has a layer of amorphous thin film material thereon comprising an alloy having a composition within a polygon in a ternary composition diagram of antimony, zinc and tin. Writing is accomplished by heating a location above the transition temperature wherein the amorphous material is converted to a crystalline material. A separate laser is shown for reading data from the rotating disk by detecting the reflectance of the alloy in either the crystalline or amorphous state. The amorphous state is very stable.
It is well known that certain polymers may undergo an irreversible index of refraction change in response to irradiation of ultraviolet light. In U.S. Pat. No. 3,689,264 which issued on Sep. 5, 1972 to E. A. Chandross et al., readily observable irreversible index of refraction changes in poly (methyl methacrylate) sensitized by the addition of ingredients to enable photo-induced cross-linking was described when irradiated with ultraviolet light from a laser.
In U.S. Pat. No. 4,994,347 which issued on Feb. 19, 1991 to W. K. Smothers, a substantially solid, storage stable photopolymerizable composition is described that forms a refractive-index image upon exposure to actinic radiation. The composition consists essentially of: a solvent soluble, thermal plastic polymeric binder; N-vinyl carbazole; and a hexaarylbiimidazole photoinitiator system having a hydrogen donor component.
In U.S. Pat. No. 4,981,777 which issued on Jan. 1, 1991 to M. Kuroiwa et al., a thin optical recording film is described comprising at least one low melting point metal, carbon and hydrogen on a substrate, and heat treating the so formed film on the substrate at a temperature of from 70° to 300° C. for a period of at least 5 seconds. The heat treatment is carried out at a temperature well below the melting point of the low melting point metal contained in the film. It has been found that the recording sensitivity of the recording film can be enhanced by the heat treatment according to the invention. By the term "enhanced recording sensitivity", it is meant reduction in energy of an energy beam such as a laser light required for recording information in unit area of the recording film. The low melting point metal element in the recording film may be tellurium, bismuth, zinc, cadmium, lead and tin used alone or in combination. The carbon content of the recording film is preferably from 5 to 40 atomic percent based on the whole film.
In U.S. Pat. No. 4,647,512 which issued on Mar. 3, 1987 to N. Venkataramanan et al., a plasma assisted chemical vapor transport process is described. The material, diamond-like carbon may be produced by plasma assisted chemical vapor transport (PACVT) process in which hydrogen is employed as the reactive process feedgas and in which the deposition process is conducted in a controllably energetic ion bombardment of the surface on which the film of diamond-like carbon is grown. Further, FIG. 4 of '512 displays the optical transmission of diamond-like carbon films obtained on KBr substrates whose intrinsic transparency is also shown in FIG. 4. The films with a thickness of about 1/2 micrometer exhibit high transparency at UV wavelength. The films exhibit a transparency of more than 50% for wavelengths above about 200 nm and more than 90% above about 400 nm. The films also exhibit a high index of refraction, about 2 at 850 nm.
The use of diamond-like carbon film as a protective coating on magnetic media has been described in U.S. Pat. No. 4,647,494 which issued on Mar. 3, 1987 to B. S. Meyerson et al. and assigned to the assignee herein. The diamond-like carbon layer provided a superior wear-resistant coating over the metallic magnetic recording layers. An intermediate layer of silicon having a minimum thickness of a few atomic layers was formed between the diamond-like carbon protective layer and the metallic magnetic recording layer to provide strong adhesion. The diamond-like carbon layer was plasma deposited.
In U.S. Pat. No. 4,833,031 which issued on May 23, 1989 to H. Kurokawa et al., a protective film was described made of a diamond-like carbon film and an organic compound film over a ferromagnetic metal recording film. The protective film provided excellent durability and small spacing loss and as a result high density magnetic recording was obtainable. The organic film on the amorphous carbon film included an organic compound having at least one fatty alkyl group having at least 8 carbon atoms at the end of a molecular structure thereof.
In a publication by A. Grill et al. entitled, "Bonding, interfacial effects and adhesion in DLC", SPIE, Vol. 969, Diamond Optics (1988), the structure and optical properties of diamond-like carbon (DLC) films are described. Diamond-like carbon films may contain sp 2 , sp 3 and even sp 1 coordinated carbon atoms in a disordered network. The ratio between the carbon atoms in the different coordinations of carbon atoms is to a great extent determined by the hydrogen content of the films. Typically, diamond-like carbon layers are seen to be weakly absorbing in the visible spectrum, tending toward transparent in the infrared spectrum. Their transparency makes diamond-like carbon films good candidates as a protective optical coating.
In a publication by V. Y. Armeyev et al. entitled, "Direct laser writing of conductive pathways into diamond-like carbon films", SPIE, Vol. 1352, Laser Surface Microprocessing, pp. 200, (1989), microprocessing of diamond-like carbon films with a continuous wave argon laser at 488 nm wavelength was described. Conductive lines were formed in the amorphous carbon films several micrometers wide having a resistivity of about 4×10 -2 Ωcm. The conductive lines were formed by graphitization as evidenced by Raman spectroscopy. The graphitization temperature threshold lies in the range from 400° to 500° C. The etching threshold where carbon is oxidized is found in the temperature range near 600° C. The use of diamond-like carbon as the active material for once-write optical recording is suggested, if the change in reflectance due to local graphitization is high enough. By using a finely focused He-Ne laser beam at 0.633 nm, the contrast in reflectivity was about 2 for scanning a graphitized spot against the as-deposited film. The graphitized strip was written at a power of 740 milliwatts.
In a publication by S. Prawer et al. entitled, "Pulsed laser treatment of diamond-like carbon films", Appl. Phys. Lett. 48, 1585 (1986), conducting pathways having a resistance of 0.10 Ωcm were formed in insulating (10 6 Ωcm) diamond-like carbon film using pulsed laser irradiation at 0.53 micrometer. Below a laser intensity threshold of 0.2 J/cm 2 of a pulsed, 70 ns, neodymium: yttrium aluminum garnet operating at 0.53 micrometers, there was no observable interaction between the laser and the film. Above 0.2 J/cm 2 , the diamond-like carbon film was partially graphitized and the effected region displayed a terrace-like structure with sharp edges. Two processes were described resulting from the interaction of the laser with the diamond-like carbon film. The diamond-like carbon film was transformed into a form of graphite for laser intensities exceeding a threshold of about 0.2 J/cm 2 and ablation of the graphite occurs.
In a publication by M. Rothschild et al. entitled, "Excimer-laser etching of diamond and hard carbon films by direct writing and optical projection", J. Vac. Sci. Technol. B, 4, 310 (1986), diamond-like carbon thin films were explored as positive-acting resist for semiconductor patterning. An ArF laser at 193 nm wavelength, was particularly suitable for interaction with diamond-like carbon, since the proton energy at this wavelength 6.4 eV is higher than the bandgap of diamond 5.4 eV. The crystal was highly absorptive. Crystalline diamond and diamond-like carbon thin films were etched with the Excimer laser. Deep structures, about 15 micrometers, were obtained in the direct write configuration and linewidths less than the laser wavelengths were generated in optical projection. The laser-induced etching takes place via surface graphitization, by a combined thermal/photochemical conversion, followed by sublimation and/or reaction.
In a publication by R. J. Gambino et al. entitled, "Spin resonance spectroscopy of amorphous carbon films", Solid State Comm., Vol. 34, pp. 15-18 (1980), printed in Great Britain, amorphous carbon was prepared by the plasma decomposition of propane providing a film which was hard, transparent, insulator much like diamond in its physical properties. The composition of amorphous carbon is described as being a random network of sp 3 and sp 2 bonded carbon with the relative fraction of each depending on the method of preparation and the process parameters.
SUMMARY OF THE INVENTION
In accordance with the present invention, a method and apparatus for storing data is described comprising the steps of: selecting an amorphous solid having atoms therein covalently bonded together, for example, diamond-like carbon, silicon carbide, boron carbide, boron nitride, amorphous silicon and amorphous germanium having a first index of refraction, and heating the amorphous solid in predetermined areas to change the index of refraction in the heated areas to a second index of refraction, the selected amorphous solid having a plurality of covalent bonds which may be modified by heating to a predetermined temperature without melting or crystallizing the amorphous solid.
It is an object of the invention to use a focussed optical or laser beam to provide a heat source to heat an amorphous solid in a localized area.
It is a further object of the invention to provide an amorphous to an amorphous transformation of a selected solid, for example, diamond-like carbon.
It is a further object of the invention to utilize diamond-like carbon as the amorphous solid and to provide a transformation of some covalent bonds from sp 2 to sp 3 whereby the density of the amorphous solid increases thereby changing the index of refraction of the material.
It is a further object of the invention to perform an amorphous to amorphous transformation of the covalently bonded material without melting the material or forming crystals therein so as to form a crystalline material.
It is a further object to provide a second stable state of amorphous material from a first state having a mixture of sp 2 and sp 3 bonds by converting sp 2 bonds to sp 3 bonds in the covalently bonded material.
It is a further object of the invention to select carbon as the amorphous material having substantially sp 3 diamond type bonding.
It is a further object of the invention to provide localized heating of a covalently bonded amorphous solid to convert sp 2 bonds to sp 3 bonds as a function of the thermal energy deposited in the localized area.
It is a further object of the invention to provide an amorphous to amorphous transformation in covalently bonded material wherein the density of the material changes resulting in a change of the index of refraction, which in turn produces a change in reflectance.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, objects, and advantages of the present invention will become apparent upon a consideration of the following detailed description of the invention when read in conjunction with the drawing, in which:
FIG. 1 shows a graph of the index of refraction versus the anneal temperature of several diamond-like carbon films;
FIG. 2 shows diamond-like carbon film patterned with an Excimer laser at 248 nm;
FIG. 3 shows one embodiment of the invention; and
FIG. 4 is a cross-section view along the line 4--4 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing, FIG. 1 shows a graph of the index of refraction versus the anneal temperature of several diamond-like carbon films. In FIG. 1, the ordinate represents the index of refraction and the abscissa represents the temperature in degrees Celsius. The diamond-like carbon films used for generating the data in FIG. 1 were formed by plasma assisted chemical vapor deposition (PACVD). Curve 12 represents data from a diamond-like carbon film deposited at a substrate temperature of 100° C. with a substrate bias voltage of -80 volts. As can be seen in FIG. 1, as the anneal temperature of a selected area of the film increases, the index of refraction likewise increases. Curve 14 shows data obtained from a diamond-like carbon film deposited on a substrate at 250° C. with a substrate bias voltage of -80 volts. Curve 16 represents data obtained from a diamond-like carbon film deposited at a substrate temperature of 250° C. with a substrate bias voltage of -150 volts. A substantial change in the index of refraction is shown in FIG. 1 when the anneal temperature is raised to a temperature in the range from 450° C. to 600° C. A film deposited at a substrate temperature of 100° C. has an index of fraction of 1.9 and an index of refraction of 2.9 after experiencing an anneal temperature of 600° C. The large change in the index of refraction can be induced by local heating of the diamond-like carbon film using a focussed laser beam. A metal film or layer 64 shown in FIG. 4 may be deposited on the substrate or disc 48 prior to depositing layer 68 which may be a diamond-like carbon film to provide a thin metallic mirror by way of layer 64 below layer 68. The thickness of the diamond-like carbon film or layer 68, which may be in the range from 4 nm to 1,000 nm, may be selected for minimum reflection which should be a thickness of one quarter wavelength or a multiple of (2n+1) quarter wavelengths where n is an integer, for example about 30 nm. Information may be written into the diamond-like carbon film by local annealing of the diamond-like carbon film or layer 68 via a laser spot, or by projection of a plurality of spots, or by a suitable energy source which imparts thermal energy to the diamond-like carbon film or layer 68 which induces a change in the index of refraction of the diamond-like carbon film or layer 68 in the selected area, a change in reflectance and a change in layer 68 thickness.
After information is written into the diamond-like carbon film, the information may be read out many times which is described in more detail in reference to FIG. 3. A light beam 84 scans the diamond-like carbon film or storage media 50 as it moves below light beam 84 on disc 48 shown in FIG. 3 and detects the index of refraction or the reflectance such as by a laser beam 84 which is reflected from the metal mirror or layer 64, shown in FIG. 4, below the diamond-like carbon film or storage media 50 and from the diamond-like carbon film or storage media itself. The reflected beam, which is intensity modulated as it scans the diamond-like carbon film or storage media 50, may be detected or sensed by a photo diode and allows data to be read back from the storage media due to the different intensity levels of reflected light, due to the variation in the index of refraction of the unexposed and the exposed areas of storage media 50. The photo diode may be a quadrant detector to provide tracking information to a servo control loop for pointing light beam 84. Light beam 84 should be monochromatic light for focussing but does not need to be coherent. A non-laser light source that is monochromatic would be suitable.
FIG. 2 shows a diamond-like carbon film patterned with an Excimer laser at 248 nm. In FIG. 2, a thin film 20 of diamond-like carbon was deposited on a substrate 21 by plasma assisted chemical vapor deposition technique (rf or dc powered) with a thickness on the order of 60 nm. The feedgas supplied to the reactor was acetylene or cyclohexane or any other hydrocarbon gas or vapor. The pressure during PACVD was in the range from 30 to 300 m torr. Thin film 20 was low in hydrogen content. Thin film 20 typically contains 10 to 50 atomic percent hydrogen. A metal mask (not shown) having openings therein was placed over the thin film 20. Thin film 20 was exposed through openings in the metal mask to radiation at 248 nm from an Excimer laser with a sequence of 8 pulses, each pulse having an energy density of 133 mJ/cm 2 . Each laser pulse may have a pulse width in the range from 10 to 50 nanoseconds and a repetition rate of 1 hertz. It is believed that the diamond-like carbon film 20 is cooled down during the 1 second after each laser pulse. The laser pulse may have an energy density in the range from 100 to 200 mJ/cm 2 . By utilizing a wavelength from the laser of 248 nm, the minimum focussed spot size may be in a range from 0.3 to 0.5 micrometers. Therefore, the density of the data stored on respective areas of film 20 is controlled by the diffraction limited optics, i.e., the minimum spot size that may be focused. In FIG. 2, squares 22 through 29 show film 20 after being annealed by 8 pulses from an Excimer laser. Each square is approximately 600 micrometers on a side. Stripes 31 through 35 shown in FIG. 2 are parallel to one another, 50 micrometers wide and spaced apart from one another by 50 micrometers and about 700 micrometers long. The light contrast in unexposed film 37 which are light compared to squares 22-29 and strips 31 through 35 which are dark is the result of the change of the index of refraction of the respective film squares 22-29 and stripes 31-35 following 8 laser pulses having an energy density of 133 mJ/cm 2 per pulse. After exposure of film 20 by the laser through a melt mask positioned on film 20, the metal mask was removed.
The change in the index of refraction of the diamond-like carbon film 20 is believed to be due to converting sp 2 bonds to sp 3 bonds in the exposed material on film 20 which, in turn, increases the density of the material. Examples of covalently bonded solid material include amorphous semiconductors, for example, diamond-like carbon, silicon carbide, boron carbide, boron nitride, amorphous silicon, and amorphous germanium. The existence and quantity of covalent bonds sp 2 and or sp 3 may be measured by laser Raman spectroscopy and also by Electron Energy Loss spectroscopy. It is noted that in amorphous diamond-like carbon, the sp 2 bonds are relatively weak bonds and that the diamond-like carbon structure is a 3-dimensional structure with the sp 2 bonds and the sp 3 bonds being oriented at different angles with respect to the arrangement of the atoms.
FIG. 3 shows an optical storage memory system 40 comprising a memory control unit 42, a write laser 44, a read laser 46, a disc 48 having storage media 50, and a motor 52 for moving the storage media 50. Memory control unit 42 may receive data over lead 54 for writing into storage media 50. Memory control 42 functions in response to the write data lead 54 to provide control signals and write data on lead 56 to an input of write laser 44. Write laser 44 functions to provide a laser beam 58 which is directed through lens 59 to the upper surface 690 of disc 48 to write data into storage media 50. As shown in FIG. 3, lens 59 provides a focussed laser beam 61 focussed on surface 60 of disc 48. Alternatively, lens 59 may include means to project a pattern or a plurality of spots on upper surface 60 of disc 48 to write in data. In FIG. 3, focussed laser beam 61 may include means for scanning or positioning focussed laser beam 61 with respect to upper surface 60 or motor 52 may position a selected area of surface 60 underneath focussed laser beam 61.
Memory control unit 42 may control write signals such as pulse duration, pulse repetition, pulse power or energy to write laser 44.
FIG. 4 shows a cross-section view of disc 48 along the line 4--4 of FIG. 3. Disc 48 provides a mechanical substrate for supporting storage media 50. Disc 48 may be, for example, glass, aluminum, plastic, ceramic, silicon, or other suitable material. A metal layer 64 may be deposited on the upper surface of disc 48. Metal layer 64 functions to provide a mirror to reflect optical energy arriving at its upper surface 65. Metal layer 64 may be, for example, aluminum, gold, chromium, etc. A layer 66 is deposited on upper surface 65 which may be very thin, for example, a few angstroms to several thousand angstroms thick and functions to provide an adhesion layer between metal layer 64 and a layer 68 of amorphous material to be deposited above layer 66. Layer 68 is deposited over layer 66 and may be, for example, a covalently bonded solid material selected from the group consisting of diamond-like carbon, silicon carbide, boron carbide, boron nitride, amorphous silicon, amorphous germanium or the hydrogenated forms of such materials. Hydrogenated forms of such material may have up to 50 atomic percent hydrogen. The hydrogen is covalently bonded to the carbon. The material for layer 66 is selected to provide good adhesion to layer 68 and may be, for example, silicon. The thickness of layer 68 and 66 may be adjusted to provide a quarter wavelength thickness or a multiple quarter wavelength thickness for the intended light source used to receive the minimum reflected light for writing and reading or sensing the index of refraction or the reflectance of layer 68. Using a reflection minimum as the initial state or condition of the storage media reduces the laser power or light power needed to heat selected areas of the storage media to write information in the storage media.
As shown in FIG. 3, disc 48 is supported and rotated by spindle 72. Spindle 72 is supported by bearing 74 and rotated by motor 52. A control signal from memory control unit 42 over lead 76 functions to control through control signals motor 52. Control signals on lead 76 may direct motor 52 to start, spin up to a certain RPM, to slow down and to stop. Motor 52 may rotate at, for example, 3600 RPM or 1 revolution per second. Disc 48 may rotate clockwise as shown by arrow 78 about axis 80 which passes through the center of spindle 72.
Read laser 46 provides a laser beam 82 which is directed through lens 83 to surface 60 of disc 48. Lens 82 may provide a focussed laser beam 84 which is focussed on surface 60. Memory control unit 42 provides control signals over lead 86 to read laser 46. Memory control unit 42 may direct read laser 46 at appropriate times to read data from layer 68 on disc 48 and may provide signals for positioning a focussed laser 84 on disc 48 by a positioning means (not shown). Read laser 46 functions to generate laser beam 82 which may be low power, for example, in the range from 1 to 10 milliwatts if a continuous laser beam and 1 to 10 mJ per pulse if a pulsed laser beam and to contain means for detecting changes in the reflectance or index of refraction of layer 68 of storage media 50 by way of the reflected beam from layer 68 through lens 83 to read laser 46 or through another suitable lens to another photo detector, for example, a photo diode (not shown). The intensity of the reflected beam may vary which provides an indication of the reflectance or the index of refraction. Read laser 46 functions to provide a signal over lead 88 indicative of the data stored in layer 68 by the reflectance or the index of refraction of layer 68 obtained from the reflected laser beam 84. Lead 88 is coupled to an input of memory control unit 42 which in turn may process the data, if necessary, and provides an output signal on lead 92 indicative of the data stored on storage media 50 obtained from reflected laser beam 84.
The invention is applicable to all covalently bonded amorphous materials where an amorphous to amorphous transformation may be obtained with a material having a high enough crystallization or melting temperature so that the transformation is obtained without being overridden by crystallization of the material.
While the present invention has been shown and described with respect to specific embodiments, it is not thus limited. Numerous modifications, changes, and improvements will occur which fall within the spirit and scope of the invention. | A method and apparatus for storing data is provided incorporating an amorphous solid having covalent bonds and a first index of refraction and an energy source for thermally heating selected areas of the amorphous solid to change the index of refraction without melting or substantially crystallizing the amorphous solid. The invention overcomes the problem of corrosion, moisture, or microbial attack resulting in deterioration of the storage medium over time, i.e., 100 years. | 8 |
This application is a continuation application of and claims priority under 35 U.S.C. § 120 to application Ser. No. 09/870,366, filed May 30, 2001 now U.S. Pat. No. 7,020,093. Application Ser. No. 09/870,366 is incorporated herein by reference.
FIELD OF INVENTION
This invention relates to delivery of streaming media.
BACKGROUND
Streaming media refers to content, typically audio, video, or both, that is intended to be displayed to an end-user as it is transmitted from a content provider. Because the content is being viewed in real-time, it is important that a continuous and uninterrupted stream be provided to the user. The extent to which a user perceives an uninterrupted stream that displays uncorrupted media is referred to as the “Quality of Service”, or QOS, of the system.
A content delivery service typically evaluates its QOS by collecting network statistics and inferring, on the basis of those network statistics, the user's perception of a media stream. These network statistics include such quantities as packet loss and latency that are independent on the nature of the content. The resulting evaluation of QOS is thus content-independent.
BRIEF DESCRIPTION OF THE FIGURES
FIGS. 1 and 2 show content delivery systems.
DETAILED DESCRIPTION
As shown in FIG. 1 , a content delivery system 10 for the delivery of a media stream 12 from a content server 14 to a client 16 includes two distinct processes. Because a media stream requires far more bandwidth than can reasonably be accommodated on today's networks, it is first passed through an encoder 18 executing on the content server 14 . The encoder 18 transforms the media stream 12 into a compressed form suitable for real-time transmission across a global computer network 22 . The resulting encoded media stream 20 then traverses the global computer network 22 until it reaches the client 16 . Finally, a decoder 24 executing on the client 16 transforms the encoded media stream 20 into a decoded media stream 26 suitable for display.
In the content delivery system 10 of FIG. 1 , there are at least two mechanisms that can impair the media stream. First, the encoder 18 and decoder 24 can introduce errors. For example, many encoding processes discard high-frequency components of an image in an effort to compress the media stream 12 . As a result, the decoded media stream 26 may not be a replica of the original media stream 12 . Second, the vagaries of network transmission, many of which are merely inconvenient when text or static images are delivered, can seriously impair the real-time delivery of streaming media.
These two impairment mechanisms, hereafter referred to as encoding error and transmission error, combine to affect the end-user's subjective experience in viewing streaming media. However, the end-user's subjective experience also depends on one other factor thus far not considered: the content of the media stream 12 itself.
The extent to which a particular error affects an end-user's enjoyment of a decoded media stream 26 depends on certain features of the media stream 12 . For example, a media stream 12 rich in detail will suffer considerably from loss of sharpness that results from discarding too many high frequency components. In contrast, the same loss of sharpness in a media stream 12 rich in impressionist landscapes will scarcely be noticeable.
Referring to FIG. 2 , a system 28 incorporating the invention includes a content-delivery server 30 in data communication with a client 32 across a global computer network 34 . The system 28 also includes an aggregating server 36 in data communication with both the client 32 and the content-delivery server 30 . The link between the aggregating server 36 and the client 32 is across the global computer network 34 , whereas the link between the aggregating server 36 and the content-delivery server 30 is typically over a local area network.
An encoder 38 executing on the content-delivery server 30 applies an encoding or compression algorithm to the original media stream 39 , thereby generating an encoded media stream 40 . For simplicity, FIG. 2 is drawn with the output of the encoder 38 leading directly to the global computer network 34 , as if encoding occurred in real-time. Although it is possible, and sometimes desirable, to encode streaming media in real-time (for example in the case of video-conferencing applications), in most cases encoding is carried out in advance. In such cases, the encoded media 40 is stored on a mass-storage system (not shown) associated with the content-delivery server 30 .
A variety of encoding processes are available. In many cases, these encoding processes are lossy. For example, certain encoding processes will discard high-frequency components of an image under the assumption that, when the image is later decoded, the absence of those high-frequency components will not be apparent to the user. Whether this is indeed the case will depend in part on the features of the image.
In addition to being transmitted to the client 32 over the global computer network 34 , the encoded media 40 at the output of the encoder 38 is also provided to the input of a first decoder 42 , shown in FIG. 2 as being associated with the aggregating server 36 . The first decoder 42 recovers the original media stream to the extent that the possibly lossy encoding performed by the encoder 38 makes it possible to do so.
The output of the decoding process is then provided to a first feature extractor 44 , also executing on the aggregating server 36 . The first feature extractor 44 implements known feature extraction algorithms for extracting temporal or spatial features of the encoded media 40 . Known feature extraction methods include the Sarnoff JND (“Just Noticeable Difference”) method and the methods disclosed in ANSI T1.801.03-1996 (“American National Standard for Telecommunications—Digital Transport of One Way Video Signals—Parameters for Objective Performance Specification”) specification.
A typical feature-extractor might evaluate a discrete cosine transform (“DCT”) of an image or a portion of an image. The distribution of high and low frequencies in the DCT would provide an indication of how much detail is in any particular image. Changes in the distribution of high and low frequencies in DCTs of different images would provide an indication of how rapidly images are changing with time, and hence how much “action” is actually in the moving image.
The original media 39 is also passed through a second feature extractor 46 identical to the first feature extractor 44 . The outputs of the first and second feature extractors 44 , 46 are then compared by a first analyzer 48 . This comparison results in the calculation of an encoding metric indicative of the extent to which the subjective perception of a user would be degraded by the encoding and decoding algorithms by themselves.
An analyzer compares DCTs of two images, both of which are typically matrix quantities, and maps the difference to a scalar. The output of the analyzer is typically a dimensionless quantity between 0 and 1 that represents a normalized measure of how different the frequency distribution of two images are.
The content-delivery server 30 transmits the encoded media 40 to the user by placing it on the global computer network 34 . Once on the global computer network 34 , the encoded media 40 is subjected to the various difficulties that are commonly encountered when transmitting data of any type on such a network 34 . These include jitter, packet loss, and packet latency. In one embodiment, statistics on these and other measures of transmission error are collected by a network performance monitor 52 and made available to the aggregating server 36 .
The media stream received by the client 32 is then provided to a second decoder 54 identical to the first decoder 42 . A decoded stream 56 from the output of the second decoder 54 is made available for display to the end-user. In addition, the decoded stream 56 is passed through a third feature extractor 58 identical to the first and second feature extractors 44 , 46 . The output of the third feature extractor 58 is provided to a second analyzer 60 .
The inputs to both the first and third feature extractor 44 , 58 have been processed by the same encoder 38 and by identical decoders 42 , 54 . However, unlike the input to the third feature extractor 58 , the input to the first feature extractor 44 was never transported across the network 34 . Hence, any difference between the outputs of the first and third feature extractors 44 , 58 can be attributed to transmission errors alone. This difference is determined by second analyzer 60 , which compares the outputs of the first and third feature extractors 44 , 58 . On the basis of this difference, the second analyzer 60 calculates a transmission metric indicative of the extent to which the subjective perception of a user would be degraded by the transmission error alone.
The system 28 thus provides an estimate of a user's perception of the quality of a media stream on the basis of features in the rendered stream. This estimate is separable into a first portion that depends only on encoding error and a second portion that depends only on transmission error.
Having determined a transmission metric, it is useful to identify the relative effects of different types of transmission errors on the transmission metric. To do so, the network statistics obtained by the network performance monitor 52 and the transmission metric determined by the second analyzer 60 are provided to a correlator 62 . The correlator 62 can then correlate the network statistics with values of the transmission metric. The result of this correlation identifies those types of network errors that most significantly affect the end-user's experience.
In one embodiment, the correlator 62 averages network statistics over a fixed time-interval and compares averages thus generated with corresponding averages of transmission metrics for that time-interval. This enables the correlator 62 to establish, for that time interval, contributions of specific network impairments, such as jitter, packet loss, and packet latency, toward the end-user's experience.
Although the various processes are shown in FIG. 1 as executing on specific servers, this is not a requirement. For example, the system 28 can also be configured so that the first decoder 42 executes on the content-delivery server 30 rather than on the aggregating server 36 as shown in FIG. 1 . In one embodiment, the output of the first feature extractor is sent to the client and the second analyzer executes at the client rather than at the aggregating server 36 . The server selected to execute a particular process depends, to a great extent, on load balancing.
Other embodiments are within the scope of the following claims. | A method for evaluating an end-user's subjective assessment of streaming media quality includes obtaining reference data characterizing the media stream, and obtaining altered data characterizing the media stream after the media stream has traversed a channel that includes a network. An objective measure of the QOS of the media stream is then determined by comparing the reference data and the altered data. | 7 |
TECHNICAL FIELD
The present invention relates generally to dynamic memory devices and particularly to devices capable of self refreshing.
BACKGROUND
Dynamic memory requires periodic refreshing to maintain the data stored in the memory. Though problems solved by the present invention apply to many types of dynamic memory, consider for this introduction a dynamic memory having an array of cells, each cell storing data as a charge on a cell capacitance.
Refreshing is accomplished by selecting a cell to refresh and recharging the cell capacitor. For memory with self refreshing capability, the act of selecting a cell to refresh is accomplished by refreshing circuits packaged with the memory. Refreshing circuits generally employ an address counter and clock oscillator for selecting a cell to refresh. Refreshing is performed in a so-called refresh cycle during which the address counter is incremented, a cell is selected, and a period of time is allowed for recharging the cell capacitor.
When the memory is performing self refreshing, refresh cycles are back to back, excluding other uses for the memory such as system read/write functions. Thus, when the system in which the memory exists requires use of the memory and the memory is currently performing self refreshing, the current refresh cycle must be terminated quickly so that the memory can respond to a read/write cycle as directed by the system.
When a system read/write cycle is begun soon after self refreshing has been interrupted, the cell selected during the last refresh cycle may not be properly refreshed. In an extreme case, the data stored in the cell is corrupted. Manufacturers of dynamic memory publish timing guidelines for systems designers including a time t RPS required between an interruption of self refreshing and the beginning of the earliest subsequent system read/write cycle. Systems designs, therefore, accommodate the time t RPS to avoid the possibility of improper refreshing and data corruption.
In the conventional dynamic memory capable of self refreshing, back to back refresh cycles are initiated in the absence of cycle by cycle signaling from the system to the memory. In addition, there is no signaling from the memory to the system indicating the beginning of a self refresh cycle. Consequently, there is no way to determine whether a given time is within t RPS for a particular memory device or a production lot of memory devices.
Thus, there remains a need for self refresh circuitry and methods that permit measurement of the shortest delay between interruption of self refreshing and the beginning of a system read/write cycle. In the absence of measurement, manufacturer's published timing guidelines include unnecessarily long delay allowances based on worst case conditions and margins for fabrication process variation. Without measurement, system designs must accommodate these conservative estimates of the delay resulting in poor system performance, slow system response, low system throughput, and generally limited system capability.
SUMMARY
Accordingly, a memory in one embodiment of the present invention includes a dynamic cell for data storage, means for storing and recalling data, means for self refreshing additionally responsive to a control signal, and means for generating the control signal in response to detecting a test signal.
According to a first aspect of such a memory, a sequence of signals to and from the memory verifies self refreshing, i.e. that the last refresh cycle prior to interruption was completed properly.
According to another aspect, the last refresh cycle is begun at a known time, i.e. the time the test signal is received by the memory, permitting worst case testing. For example, a delay between interruption of self refreshing and the beginning of a system read/write cycle can be verified in the worst case when interruption (signalled to the memory) immediately follows initiation of the last refresh cycle (signalled to the memory).
According to yet another aspect, the test signal comprises a voltage different from the voltage of signals the memory receives during non-test operations and there are no additional interface lines needed to practice the invention. Therefore, systems designed for conventional memory are compatible with memory of the present invention.
The present invention may be practiced according to a method which includes in one embodiment the steps of storing data in the cell; enabling self refreshing; directing self refreshing by inputting to the memory a test signal so that refreshing of the cell begins after receipt of the test signal; disabling self refreshing at a first time; reading data from the cell at a second time; and determining that the period from the first time to the second time is sufficient for refreshing by comparing the data read to the data stored.
According to a first aspect of such a method, exhaustive testing of the memory can be accomplished in reasonable time by arranging the second time to occur at a worst case interval from the first time.
In another embodiment of the present invention, a memory includes a dynamic storage cell, means for read and write access, means for refreshing, and means for detecting a test signal. The refreshing means refreshes the cell after an absence of read and write control signals for a first time. In response to a third control signal, the refreshing means refreshes the cell and provides a refresh cycle signal. The detecting means enables outputting of the buffered third control signal in response to the test signal.
According to a first aspect of such a memory, t RPS can be measured as the time between the buffered third control signal output from the memory and a subsequent read control signal.
The present invention may be practiced with such a memory according to a method which includes in one embodiment the steps of storing data in the cell; enabling self refreshing; enabling the output of a refresh cycle signal occurring at a first time; disabling self refreshing at a second time; reading data from the cell; and determining that the period from the first time to the second time is sufficient for refreshing by comparing the data read to the data stored.
According to a first aspect of such a method, measurement of t RPS involves less circuitry in the memory and in the test setup.
According to another aspect of such a method, the measurement system can verify memory operation at a given t RPS without knowledge of the duration of a refresh cycle.
These and other embodiments, aspects, advantages, and features of the present invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art by reference to the following description of the invention and referenced drawings or by practice of the invention. The aspects, advantages, and features of the invention are realized and attained by means of the instrumentalities, procedures, and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional block diagram of a dynamic memory of an embodiment of the present invention.
FIG. 2 is a functional block diagram of a portion of refresh controller 24 shown in FIG. 1.
FIGS. 3 and 4 are timing diagrams of signals shown in FIG. 2.
FIG. 5 is a schematic diagram of portions of refresh controller 24 shown in FIG. 2.
FIG. 6 is a functional block diagram of another embodiment of a portion of refresh controller 24 shown in FIG. 1.
FIG. 7 is a timing diagram of signals shown in FIG. 6.
FIG. 8 is a schematic diagram of mode logic 410 shown in FIG. 6.
In each functional block diagram, a broad arrow symbolically represents a group of signals that together signify a binary code. For example, a group of address lines is represented by a broad arrow because a binary address is signified by the signals taken together at an instant in time. A group of signals having no binary coded relationship is shown as a single line with an arrow. A single line between functional blocks represents one or more control signals.
Signals that appear on several Figures and have the same mnemonic are directly or indirectly coupled together. A signal named with a mnemonic and a second signal named with the same mnemonic followed by an asterisk are related by logic inversion.
In each timing diagram the vertical axis represents binary logic levels and the horizontal axis represents time. Neither axis is drawn to scale. The vertical axis is intended to show the transition from active (asserted) to passive (non-asserted) states of each logic signal. The voltage levels corresponding to the logic states of the various signals are not necessarily identical among the various signals.
DESCRIPTION
FIG. 1 is a functional block diagram of a dynamic memory of one embodiment of the present invention. Memory device 10 is controlled by binary control signals input on lines 41 through 44 from the device pads to read/write control 12. Control signals on lines 41-44 are conventionally known by names corresponding to the primary function of each signal. The primary signal on line 41 is row address strobe (RAS*; on line 42 is column address strobe (CAS*); on line 43 is write enable (WE*), and on line 44 is output enable (OE*). When RAS* falls, the state of address bus 60 is latched in row address buffer 30 in response to control signals on line 68. When CAS* falls, the state of address bus 60 is latched in column address logic 18 in response to control signals on line 62.
Several read and write modes of operation (also called cycles) are conducted by read/write control 12 in response to address change signals on line 64 and combinations of control signals on lines 41-44. For example, read/write control 12 responds to changes in the column address as indicated by address change signals on line 64 for improved access time as in page mode. Read/write control 12 generates control signals on lines 48-58 for two different write cycles. The first, early write, follows a RAS*, WE*, CAS* control signal sequence. The second, late write, follows a RAS*, CAS*, WE* control signal sequence.
When RAS* falls while CAS* is low, read/write control 12 provides signals on line 66 to refresh controller 24 to enable self refreshing. In one embodiment, the group of signals shown as line 66 includes RAS*, CAS*, and WE* from lines 41, 42, and 43. Refresh controller 24 includes a clock circuit and means for selecting a cell to refresh. During self refresh mode, refresh controller 24 generates signals on refresh row address bus 82 (for example, as generated by the output of a refresh row address counter or register clocked by an oscillator) to select a row of cells to refresh. Row address buffer 30 provides signals on row address bus 84 to row decoder 26. Signals on binary row address bus 84, in response to control signals on line 68, represent either the address latched when RAS* falls or the refresh row address, depending on the mode of operation. During a refresh cycle, data signals on lines 80 from the selected row are amplified by sense amplifiers 22 causing cells in the row to be refreshed.
In addition to cell refreshing, sense amplifiers 22 respond to control signals on line 56 and column decoder signals on line 72 to perform the memory read cycle. Signals RAS*, CAS*, WE* (high), and address signals A0 through A9 cooperate to provide a control signal for a read cycle. In read operations cell content signals on lines 80 are amplified and presented to data out buffers 16 as global I/O signals on line 74. When cell contents are to be overwritten in a write operation, sense amplifiers 22 establish proper cell contents in response to write data signals on line 76 from data-in buffers 14.
Data-in buffers 14 are instrumental for write operations. Signals RAS*, CAS*, WE* (low), OE*, and address signals A0 through A9 cooperate to provide a control signal for a write cycle. In write operations cell contents are changed to correspond to the outputs on line 76 of data-in buffers 14. Data in buffers 14 are driven by data bus 50 which comprises several individual data lines shown as DQ n .
Memory device 10 has eight DQ lines, each of which is bidirectional. Alternate memory devices may have less or more DQ lines and may have separate lines for the data-in (D) function and the data-out (Q) function. In memory device 10, each bidirectional line is driven by a three state circuit to represent a logic low, a logic high, or an off state. In the off state, the three state circuit connects a high impedance to the DQ line so that drive circuits external to memory device 10 can drive a signal onto the DQ line for data-in buffer 14.
Improved timing test capability is provided in memory 10 in one embodiment by the cooperation of signals on lines 41-43, a signal on line 61, and novel functions of refresh controller 24. Line 61 represents one of the signal lines for signals A0 through A9. A signal on line 61 and a signal on line 43 cooperate to provide a test signal.
In another embodiment improved timing test capability is provided by the cooperation of signals on lines 41, 42, a signal on line 61, and novel functions of data-out buffers 16. The test signal in the later embodiment includes a signal on line 61 without reference to signals on line 43. Realization of improved timing test capabilities will become more apparent upon review of lower level block diagrams to be discussed.
In an equivalent dynamic memory, not shown, storage cells are arranged in a ring rather than in a row-column array as shown in FIG. 1. In such an arrangement, control and address signals different from those shown in FIG. 1 comprise the control signals for a read and a write operation. Storage ring architectures include magnetic bubble and charge coupled devices as is well known in the art.
In another equivalent memory, not shown, memory 10 additionally includes serial access means coupled to sense amplifiers 22 for providing serial access between the memory array and a serial input/output buffer circuit. In such a memory, control signals 56 include a transfer signal for enabling data transfer between array 28 and the serial access means.
FIG. 2 is a functional block diagram of a portion of refresh controller 24 shown in FIG. 1. The output of the circuit shown is signal IRAS on line 148 which is used as an internal row address strobe. In response to IRAS, a row is selected for refreshing, and a refresh row address counter, not shown, is incremented. IRAS in the embodiment shown is used to indicate the beginning of each row-by-row refresh cycle after refreshing has been initiated.
RAS logic 112 monitors signals RAS* and CAS* to detect when to initiate and terminate self refreshing and consequently generates control signals. Signal TRAS on line 134 is generated as a pulse of predetermined length and used to establish a proper pulse width for signal IRAS on line 148. The formation of the TRAS signal is triggered by signal IRAS input to RAS logic 112. Signal SRAS* on line 136 is generated by buffering signal RAS* so that termination of self refreshing follows soon after the rising edge of signal RAS*. The beginning of a CAS* before RAS* self refresh cycle is indicated by signal CBR* on line 137 for controlling refresh clock generation.
Oscillator control 114, responds to signals SRAS* and CBR* to enable oscillator 116 to oscillate during self refreshing. Oscillator 116, when enabled, generates, in one embodiment a clock having a period of about two microseconds as signal CK2US on line 140. A second clock having a period twice as long as the period of signal CK2US on line 142 results from division of signal CK2US. These clock signals are used for measuring time using a counter.
Modulo N counter 122 responds to the clock signal on line 144, selected by multiplexer 120, and to a load signal LD on line 150. Counter 122 loads an initial count in response to signal LD and counts clock signals on line 144 until a terminal count is reached, whereupon signal CKR is generated on line 154. The internal RAS signal, IRAS, is developed from signal CKR via mode logic 128 or from signal TEST2 in cooperation with signal TEST1 via multiplexer 124.
Mode logic 128 holds counter 122 at the initial count when oscillator 116 is not enabled. When oscillator 116 is enabled, mode logic 128 generates signal LD on line 150 after the terminal count is reached, as indicated by signal CKR. In the embodiment shown, signal CKR is used to form a pulse signal CKS* on line 151. The CKS* pulse is then gated through multiplexer 124 as self refresh pulse signal SRP on line 146.
Mode logic 128 controls counter 122 as a timer for measuring the self refresh setup time and the self refresh cycle time. When signal CBR* indicates self refreshing may begin, mode logic 128 holds self refresh mode signal SREF on line 152 low so that slower clock signal CK4US is coupled to counter 122. Self refresh cycles do not begin before a self refresh setup time has elapsed during which neither a read signal nor a write signal occurs, i.e. while signal CBR* remains asserted and signals RAS* and CAS* are absent. The self refresh setup time has elapsed when the terminal count occurs and signal CKR issues as a consequence of the rate prescribed by signal CK4US and the magnitude of the initial and terminal counts.
Mode logic 128 raises signal SREF after the first terminal count is reached. When signal SREF on line 152 is high (asserted), faster clock signal CK2US is used to measure the time between back to back refresh cycles. In the embodiment shown, the self refresh setup time is twice the self refresh cycle time and the initial count is fixed as a metal mask option during integrated circuit fabrication. Those skilled in the art understand that a selection of initial counts could be used as the functional equivalent of clock division and selection. Also, accommodation of an other than two to one relationship between the self refresh setup time and the self refresh cycle time (for example, to support burst refreshing) involves mere design choice in clock rate, initial count, terminal count, and mode logic.
After self refresh mode is entered, as indicated when signal SREF is asserted, subsequent CKR signals are coupled as CKS* signals through multiplexer 124. Signal SREF, when asserted, also enables gate 126 so that multiplexer output signal SRP on line 146 is combined in a logic `or` with signal TRAS through gate 126.
Self refresh mode is interrupted by a test signal to direct the initiation of a final refresh cycle prior to terminating self refreshing. In the embodiment shown, the test signal includes a high voltage signal on a line used otherwise for an address signal and includes a pulse on a line used otherwise for a write enable signal. Super voltage detector 110 operates as a means for providing a multiplexer control signal (SV). Detector 110 and selection logic in multiplexer 124 cooperate as a means for detecting the test signal. Detector 110 includes a comparator for comparing a signal TEST1 on line 61 to a fixed threshold voltage. The threshold voltage is selected by design so as to be easily distinguishable from non-test related signals. Although a distinguishable voltage magnitude is used in the embodiment shown, virtually any other signalling characteristic could be used, with appropriate means for detecting the test signal. In the embodiment shown, memory device 10 is powered by a supply voltage and the magnitude of the supply voltage is used as the threshold. When the threshold is exceeded, detector 110 provides signal SV on line 132.
After signal SV has been asserted, a time sufficient for the presently occurring refresh cycle to be completed must pass. Then, to initiate the final refresh cycle, a pulse signal TEST2 on line 43 is gated through multiplexer 124 to generate the IRAS signal. The IRAS signal, so generated, triggers signal TRAS through RAS logic 112 which in turn forms the IRAS pulse of the proper duration by operation of gate 126. The operation of a circuit embodiment of the functions shown in FIG. 2, especially operation to measure time t RPS , will be better understood with reference to a timing diagram.
FIGS. 3 and 4 are timing diagrams of signals shown on FIG. 2. FIGS. 3 and 4 present five consecutive cycles. An early write cycle is presented from time T10 to time T22 wherein data is stored in a cell of the dynamic memory. A conditional cycle satisfying a self refresh setup time specification from time T22 to time T41 is followed by self refreshing from time T41 to time T78. During self refreshing, a self refresh cycle is illustrated from time T41 to time T52 and a directed final refresh cycle is shown from time T60 to time T78. Finally, a read cycle for reading data from a cell of the dynamic memory is presented from time T78 to time T90.
To verify that a period shown between time T70 and time T80 meets a t RPS specification for memory 10, data is stored in the array via a plurality of write cycles. After all cells in the array have been written to a known state, self refreshing is enabled. Signal CAS* falls before signal RAS* at time T22. When both signals are low, signal OEN* enables oscillator 116 and disables continuous loading of counter 122 so that counting can begin. Counter 122 measures the self refresh setup time from time T28 to time T36, then is reloaded at time T41 to measure the time between back to back refresh cycles.
The first self refresh cycle extends from time T41 to time T52. At the end of the cycle, the first occurrence of self refresh pulse signal SRP in self refresh mode (SREF high) raises IRAS. IRAS pulse width is extended by the duration of signal TRAS and falls at time T58 after TRAS falls at time T56. The period from time T46 to time T58 has been greatly expanded to show the causative relations between signals. In one embodiment the period from time T42 to time T46 is about 125 microseconds and the period from time T46 to time T58 is about 2 microseconds.
Self refreshing is interrupted at time T60 when signal SV is raised as shown on FIG. 4. When signal SV is raised, signal SRP is no longer generated as a consequence of reaching the terminal count. Because counter 122 may not be at the initial count when signal SV was raised, a period greater than or equal to one refresh cycle duration must pass from time T60 before directing the final refresh cycle via signal TEST2 at time T66.
At time T66, a low true pulse signal TEST2 on line 43 is gated through multiplexer 124 to form signal SRP and gated through gate 126 to form signal I RAS. The pulse width of signal IRAS is extended until after signal TRAS falls at time T72.
At time T70, signal RAS* is raised to terminate self refreshing. RAS logic 112, in response to RAS* high takes CBR* high so that, in the absence of signals CBR* and IRAS, oscillator control 114 raises signal OEN*, terminating oscillation at time T76. In response to OEN* high, mode logic 128 forces counter 122 to the initial count by raising signal LD at time T78. Finally, mode logic 128 takes signal SREF low to disable gate 126 and to provide signal CK4US to counter 122 in preparation for the next conditional cycle.
At time T80, signal RAS* falls to test whether a period from time T70 to the time RAS* falls satisfies a minimum t RPS timing specification, i.e. whether the time T70 to the time RAS* fell was sufficient for proper refreshing of the cell or cells addressed in the final refresh cycle. If data (at the address used in the final refresh cycle) as read via a read cycle illustrated from time T80 to time T90 does not match the data previously stored at that address, the time from time T70 to the time signal RAS* fell did not meet the minimum t RPS specification. When the address used in the final refresh cycle is not known, all addresses are read and compared to data previously stored, for example, during the write cycle beginning at time T10. Having discussed how to test a minimum t RPS specification, we now turn to a circuit realization of the block diagram.
FIG. 5 is a schematic diagram of portions of the refresh controller shown in FIG. 2. Mode logic 128 is shown with portions of other circuitry to which it connects. Because the implementation is asynchronous, delay elements such as 213 and 222 have been included to eliminate race conditions between signals. The extent of delays shown and additional delays not shown depend on the propagation delay characteristics of the devices selected by the designer to carry out the invention. Timing analysis and circuit modification are conventional steps in asynchronous logic design and are well understood in the art.
In oscillator control 114, signal OEN* is developed from the logic combination of signals SRAS* and CBR*. Signal IRAS serves to lengthen the time during which signal OEN* is asserted.
In multiplexer 124, when signal SV is low, a low true pulse signal CKS* at inverting input `A` is coupled to output `Y`. Similarly, when signal SV is high, signal TEST2 at inverting input `B` is coupled to output `Y`. A delay element 213 is interposed in the output circuit to avoid the generation of unwanted signals at the output of gates 228 and 214.
Gate 126 is implemented with or-gate 214 and and-gate 216. In an equivalent embodiment, not shown, signal SREF controls the output circuitry of gate 214 so that signal IRAS is generated without interposing the propagation delay of gate 216.
Mode logic 128 includes an edge triggered pulse generator circuit and a flip-flop circuit. Delay element 222 and gates 224 and 226 cooperate to form a pulse from the rising edge of signal CKR. Gates 230 and 232 form a flip-flop for generation of signal SREF. When signal OEN* is high, gate 232 generates a low SREF signal. When signal OEN* is low, the flip-flop maintains its prior state (SREF low) until the output of gate 228 goes high, which occurs for example at time T38 on FIG. 4. Operation of the flip-flop prevents a pulse from appearing on line 148 during the conditional cycle.
FIG. 6 is a functional block diagram of another embodiment of a portion of refresh controller 24 shown in FIG. 1. Similarly identified signals, lines, and functional blocks shown in FIG. 2 and in FIG. 6 perform identical functions. Differences between the two figures include deletion of multiplexer 124 from FIG. 6, replacement of mode logic 128 with mode logic 410, and addition of gates 125 and 127.
The test signal for the embodiment shown in FIG. 6 is signal TEST1 on line 61. When the magnitude of signal TEST1 exceeds a threshold voltage, super voltage detector 110 produces signal SV on line 132 in a manner as already discussed with FIG. 2. Signal SV and signal SREF on line 152 are combined by gate 125 to enable gate 127 during self refreshing. When enabled, a buffered IRAS signal (BIRAS) is provided on line 156 in response to signal IRAS on line 148. Line 156 is one of several individual data lines which comprise data bus 50, shown in FIG. 1. As shown in FIG. 6, the signal appearing on line 156 is a buffered IRAS signal when signal SV is asserted during self refreshing, and is a DQ signal, for example DQ0, otherwise.
FIG. 7 is a timing diagram of signals shown on FIG. 6. FIGS. 3 and 7 taken together present five cycles. The early write cycle, conditional cycle, and first self refresh cycle have already been discussed. The later portion of the final refresh cycle, illustrated from time T110 to T130 on FIG. 7, differs from the directed final refresh cycle shown on FIG. 4. Differences will be discussed below. The read cycle for reading data from a cell of the dynamic memory is presented from time T130 to time T142 and is identical to the read cycle shown on FIG. 4.
To verify that a time period shown between time T120 and time T132 meets a t RPS specification for memory 10, data is stored in the array via a plurality of write cycles. After all cells in the array have been written to a known state, self refreshing is enabled and a first refresh cycle occurs as shown on FIG. 3. For the embodiment shown in FIG. 6, signal SV is asserted at any time prior to the final cycle, for example at time T110. Each subsequently occurring IRAS signal will be coupled to line 156 as signal BIRAS. The terminal count of counter 122 is reached at time T114 raising signal CKR. Between times T114 and T126, signals CKR, SRP, IRAS, TRAS, and LD are formed in the manner described with reference to FIG. 3 between times T46 and T58.
Self refreshing is interrupted at time T120 when signal RAS* goes high, illustrating a worst case t RPS scenario. As shown, signal RAS* goes high just as a refresh cycle has begun as indicated by signal BIRAS. After signal TRAS falls at time T124, signal IRAS falls at time T126 and signal BIRAS falls at time T128. RAS logic 410, in response to RAS* high takes CBR* high so that, in the absence of signals CBR* and IRAS, oscillator control 114 raises signal OEN*, terminating oscillation at time T128. In response to OEN* high, mode logic 410 forces counter 122 to the initial count by raising signal LD at time T130. Mode logic 410 takes signal SREF low to disable gate 126 and to provide signal CK4US to counter 122 in preparation for the next conditional cycle. Finally, signal SV is removed prior to the next refresh cycle, for example, at time T134.
At time T132, signal RAS* falls to test whether a time T120 to the time RAS* falls satisfies a minimum t RPS timing specification, i.e. whether the time T120 to the time RAS* fell was sufficient for proper refreshing of the cell or cells addressed in the final refresh cycle. If data (at the address used in the final refresh cycle) as read via a read cycle illustrated from time T130 to time T142 does not match the data previously stored at that address, the time from time T120 to the time signal RAS* fell did not meet the minimum t RPS specification. When the address used in the final refresh cycle is not known, all addresses are read and compared to data previously stored, for example, during the write cycle beginning at time T10. Having discussed how to test a minimum t RPS specification using the embodiment shown in FIG. 6, we now turn to a circuit realization of the block diagram.
FIG. 8 is a schematic diagram of mode logic 410 shown in FIG. 6. Similarly identified signals, lines, and functional blocks shown in FIG. 5 and in FIG. 8 perform identical functions. In FIG. 8, signals OEN*, CKR, SREF, and LD operate in the manner as already discussed with FIG. 2 and with timing diagrams in FIG. 3 and FIG. 7. The output of gate 226 shown in FIG. 8 provides signal SRP on line 146. In other respects, signal SRP operates in the manner already discussed with FIG. 2 and with timing diagrams in FIGS. 3 and 7.
When making a measurement of the time t RPS using an embodiment consistent with signal timing shown in FIG. 4, the signal RAS* should be taken high with or as soon after the signal TEST2 is taken low. Although signal transitions shown on FIG. 4 are spatially separated to clearly show causative relations, the figure is not to scale and near simultaneous transitions are within the scope of the invention disclosed. If other than simultaneous transitions of RAS* and TEST2 are used in the measurement, the skilled artisan knows to make an allowance for the extent of time between the falling edge of signal TEST2 and the rising edge of signal RAS* for an accurate measurement.
When making a measurement of t RPS using an embodiment consistent with signal timing shown in FIG. 7, the signal RAS* should make a transition soon after the rising edge of signal BIRAS. Although the signals are shown as occurring at time T120, the skilled artisan knows to make an allowance for the actual extent of time between the rising edge of signal BIRAS and signal RAS* for an accurate measurement.
The inventor considers embodiments consistent with FIG. 2 to be preferred because measurement of t RPS can be made with somewhat greater accuracy as discussed above. In embodiments consistent with FIG. 6, signal BIRAS is coupled to a DQ line through data-out buffers 16 which may add a delay that is difficult to predict due to variation in the fabrication process.
In an alternate and equivalent embodiment not shown, counter 122 is eliminated. As is well known in the art, the generation of signal CKR can be accomplished by an oscillator without frequency division.
The foregoing description discusses preferred embodiments of the present invention, which may be changed or modified without departing from the scope of the present invention.
For example, those skilled in the art understand that the logical elements described above may be formed using a wide variety of logical gates employing any polarity of input or output signals and that the logical values described above may be implemented using different voltage polarities. As an example, an AND element may be formed using an AND gate or a NAND gate when all input signals exhibit a positive logic convention or it may be formed using an OR gate or a NOR gate when all input signals exhibit a negative logic convention.
These and other changes and modifications are intended to be included within the scope of the present invention.
While for the sake of clarity and ease of description, several specific embodiments of the invention have been described; the scope of the invention is intended to be measured by the claims as set forth below. The description is not intended to be exhaustive or to limit the invention to the form disclosed. Other embodiments of the invention will be apparent in light of the disclosure to one of ordinary skill in the art to which the invention applies.
The words and phrases used in the claims are intended to be broadly construed. A "system" refers generally to electrical apparatus and includes but is not limited to a packaged integrated circuit, an unpackaged integrated circuit, a combination of packaged or unpackaged integrated circuits or both, a microprocessor, a microcontroller, a memory, a register, a charge-coupled device, combinations thereof, and equivalents.
A "signal" refers to mechanical and/or electromagnetic energy conveying information. When elements are coupled, a signal can be conveyed in any manner feasible in light of the nature of the coupling. For example, if several electrical conductors couple two elements, then the relevant signal comprises the energy on one, some, or all conductors at a given time or time period. When a physical property of a signal has a quantitative measure and the property is used by design to control or communicate information, then the signal is said to be characterized by having a "value." For a binary (digital) signal, the two characteristic values are called logic "levels." | A dynamic memory having self refreshing capability performed without external strobing, is interruptable and can be strobed to initiate a refresh cycle for testing interrupt response timing. In operation of such a dynamic memory, interruption of a self refresh cycle precedes initiation of a read or write cycle by a time t RPS , sufficient for row precharge. Although t RPS can be estimated based on worst case analysis, lower t RPS characteristics can be guaranteed, resulting in higher yields, by measuring t RPS during memory fabrication using circuits and methods disclosed. In an alternate embodiment, output of a signal indicative of the beginning of a refresh cycle is enabled by a test signal. | 6 |
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] This invention relates generally to detection apparatus, and more specifically to detection apparatus of the kind including a sample inlet, an arrangement for ionizing molecules entering the apparatus via the inlet, and a drift region in which an electric field is established to draw ions away from the ionizing arrangement to an asymmetric field region in which the ions are subject to an asymmetric field for detection.
[0002] Field asymmetric ion mobility spectrometers (FAIMS) or differential mobility spectrometers (DMS) have a filter region where an electrical field is produced transverse to direction of ion flow. By appropriately setting the electrical field certain ion species can be selected to flow through the filter for detection. Most FAIMS or DMS devices have an inlet that allows gas to flow from atmosphere and transfer ions from the region of the ion source. The gas is derived from the same source as is being sampled so it does not result in any dilution of the analyte sample. This can enable very low analyte levels to be detected. A problem with this arrangement is that there can be high levels of humidity in the sample. Water molecules, being polar, cluster with the ion species and, in doing so, vary the collision cross-section of the ion species moving through the ion filter and hence alter their mobilities. This causes movement of the observed position of the spectral peaks representing arrival of the ion species in the ion detection region of the instrument.
[0003] It is an object of the present invention to provide an alternative detection apparatus and method.
SUMMARY OF THE INVENTION
[0004] According to one aspect of the present invention there is provided detection apparatus of the above-specified kind, characterized in that a source of dry gas is arranged to supply dry gas to the drift region at a location between its ends such that, for a first part of the path along the drift region, ions travel against the flow of the dry gas and, for a second part of the path, the ions travel with the flow of the dry gas. The drift region preferably includes a plurality of plates spaced from one another along the direction of travel of the ions. The plurality of plates may be arranged parallel with one another and each have an aperture therein through which the ions travel along the drift region. The asymmetric field region may include two plates extending parallel to the direction of travel and a detector located beyond the plates to detect ions passing through the two plates. The sample inlet may include a membrane permeable to the analyte, a pinhole, or a capillary inlet. The apparatus may also be arranged to supply dry gas to a location adjacent the inlet.
[0005] According to another aspect of the invention there is provided a method of detecting an analyte substance including the steps of introducing molecules of the substance via an inlet, ionizing molecules of the sample, drifting the ions formed by means of an electrical field in a direction away from the inlet and against the flow of a dry gas, subsequently drifting the ions in the same direction with the flow of the dry gas, subsequently admitting the ions to a region of a transverse electrical field so as to separate different ion species from one another, and detecting some of the ion species.
[0006] The method preferably includes the step of supplying dry gas adjacent an inside of the inlet.
DESCRIPTION OF THE DRAWING
[0007] Detection apparatus and its method of operation, in accordance with the present invention, will now be described, by way of example, with reference to the accompanying drawing, which shows the detection apparatus schematically.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0008] The detection apparatus includes an elongate housing 1 with an inlet 2 at its left-hand end covered by a membrane 3 . The membrane 3 allows molecules of the analyte of interest to enter the housing 1 , but prevents some larger molecules, particles, and the like entering. Alternatively, the inlet 2 could have any other conventional means for restricting entry, such as a pinhole inlet, a capillary inlet, or the like. The interior of the housing 1 is at substantially atmospheric pressure, although there are various gas flow paths within the housing and outside it, as will be explained later. Ions of the analyte flow along the housing 1 generally from left to right as shown in the drawing. Located immediately adjacent the inlet 2 is an ionization source 4 , which may be of any conventional kind such as a radioactive source, a corona discharge device, a photoionization source, or the like.
[0009] A drift region 6 to the right of the ionization source 4 as shown in the drawing is formed by a series of five guide electrode plates 7 extending transverse of the housing 1 axis and equally spaced parallel to one another. The electrode plates 7 are circular in shape with a central aperture 8 aligned axially with respect to the housing 1 . The electrode plates 7 are connected with a voltage source 9 that is arranged to apply successively higher voltages to each plate in the series. Different numbers and arrangements of electrodes could be used.
[0010] The apertures 8 through the series of electrode plates 7 are aligned with a gap 10 between two closely-spaced FAIMS plates 11 and 12 . The FAIMS plates 10 and 11 are flat and are connected to a conventional FAIMS power source 13 . The FAIMS power source 13 applies an asymmetric alternating voltage superimposed on a DC compensation voltage across the two FAIMS plates 11 and 12 , in the usual way. At the far end of the housing 1 remote from the inlet 2 , and beyond the right-hand end of the FAIMS plates 11 and 12 , are two small, flat detector plates 14 and 15 . The detector plates 14 and 15 extend parallel with the axis of the housing 1 and are aligned parallel with the FAIMS plates 11 and 12 respectively. The detector plates 14 and 15 are connected to an amplifier and processor 16 responsive to the charge on the detector plates 14 and 15 to provide an output to a display or other utilization means 17 indicative of the identity of the analyte sampled.
[0011] The housing 1 is connected at various locations in a pneumatic gas-flow system 20 . The gas flow system 20 includes a pump 21 having an outlet 22 connected to a molecular sieve 23 , which produces clean dry air, and which may include a dopant or reagent in the manner described in U.S. Pat. No. 6,825,460. U.S. Pat. No. 6,825,460, to Breach et al. One outlet of the molecular sieve 23 connects via an adjustable restrictor 24 to a membrane gas inlet 25 close to the inlet end of the housing 1 , between the inlet 2 and the ionization source 4 , in the region of the membrane 3 . This membrane gas flows from the inner surface of the membrane 3 to the right, to help carry analyte molecules from the membrane 3 to the ionization source 4 .
[0012] The molecular sieve 23 has a second outlet, which connects with a second housing inlet 26 located downstream (in terms of the ion flow direction), to the right of the membrane gas inlet 25 . The second inlet 26 is for flushing gas and is located between opposite ends of the drift region 6 series of electrode plates 7 and, more particularly, extends as a conduit 27 opening between the right-hand or downstream end electrode plate 7 and the adjacent electrode plate 7 . Flushing gas flows out of the end of the conduit 27 in both directions, that is, downstream, towards the detector plates 14 and 15 , and upstream, towards the inlet 2 .
[0013] The gas-flow system 20 also includes two outlets 29 and 30 on the housing 1 . One outlet 29 is located towards the inlet end of the housing 1 and, more particularly, is located upstream of the ion flow relative to the outlet of the conduit 27 , that is, longitudinally between the two inlets 25 and 26 . This outlet 29 connects via an adjustable restrictor 31 with an inlet of the pump 21 . The other outlet 30 is located centrally at the right-hand end of the housing 1 , downstream of detector plates 14 and 15 . This outlet 30 may also connects via an adjustable restrictor with an inlet of the pump 21 .
[0014] In operation, analyte molecules in sample air pass through the membrane 3 at the inlet 2 and are carried in the flow of membrane gas from the inlet 25 to the ionization source 4 where the molecules are ionized. The ion species produced continue flowing to the right under the combined effect of the flow of membrane gas and the opposite, attractive electrostatic charge on the left-hand electrode plates 7 in the drift region 6 . When the ion species enter the drift region 6 , the flow of gas from the outlet 26 against the ion flow exceeds that of the membrane gas flow so the ion species travel against the net gas flow, only under the influence of the electric field established in the drift region 6 . This counter flow of dry gas is effective to remove water molecules from the analyte, which are carried via the outlet 29 to the pump 21 and the molecular sieve 23 , where they are removed.
[0015] When the ion species come level with the flushing gas inlet 26 , they experience a change of gas flow direction, which is now downstream, from left to right as shown in the drawing, and is effective to drive the ion species out and away from the drift region 6 . This effect may be increased by arranging for the charge on the right-hand electrode plate 7 in the drift region 6 to be of the same sense as the charge on the ions so that a repulsive force is experienced by the ions species. The charge on the two FAIMS plates 11 and 12 is also such as to attract the ion species into the gap 10 . The flushing gas from the inlet 26 flows to the right, downstream through the gap 10 and around the outside of the FAIMS plates 11 and 12 to the gas outlet 30 where it flows to a second inlet of the pump 21 for recirculation.
[0016] The ions species move along the gap 10 under the combined effect of the electrostatic field and the gas flow.
[0017] The applied FAIMS field acts to separate out the different ion species from one another and the DC compensation voltage applied to the FAIMS plates 11 and 12 is selected such that some at least of the ion species that are not of interest are attracted to one or other of the FAIMS plates 11 and 12 where they are neutralized. The remaining ion species flow along the entire length of the gap 10 without contacting the FAIMS plates 11 and 12 and are collected by one or other of the detector plates 14 or 15 . Other FAIMS or DMS arrangements could be used.
[0018] The gas flow arrangement of the present invention enables a substantial reduction in the effect of humidity to be achieved in a FAIMS spectrometer.
[0019] Although the foregoing description of the detector apparatus present invention has been shown and described with reference to particular embodiments and applications thereof, it has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the particular embodiments and applications disclosed. It will be apparent to those having ordinary skill in the art that a number of changes, modifications, variations, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. The particular embodiments and applications were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such changes, modifications, variations, and alterations should therefore be seen as being within the scope of the present invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. | An ion mobility spectrometer has an inlet opening into an ionization region including a conventional ionization source. A series of several charged, circular electrode plates with aligned apertures extending therethrough provides a drift region on the opposite side of the ionization region from the inlet. A gas inlet connected to a source of clean, dry flushing gas opens between the ends of the drift region, with the gas flowing against the ion flow to one side to remove water molecules from the analyte. Gas flowing in the opposite direction is effective to help drive the dry analyte ions to an analysis region provided by two parallel asymmetric field plates. | 6 |
FIELD OF THE INVENTION
This invention relates to valves for controlling the filling of liquid tanks, and more particularly to an improved fill valve responsive to the position of a float.
DESCRIPTION OF THE PRIOR ART
Many different types of fill valves for controlling the level of liquid in a tank are known. In general such fill valves include position for sensing liquid level in a tank. A float is often employed. A valve operated in response to the float position permits flow from a liquid supply to the interior of the tank when the level drops below a predetermined level maintained by the valve. Fill valves of this type are used in toilet water tanks to maintain the water at a selected level and to refill the tank following a flush cycle during which the tank is emptied.
Snyder U.S. Pat. No. 1,037,679 discloses a flushing apparatus with a valve 3 controlled by a main float 23 and an auxiliary float 13. The auxiliary float 13 is a receptacle mounted for limited vertical movement and has an opening normally closed by a flap or check valve 17. When the tank is emptied, the auxiliary receptacle moves down, the flap valve 17 opens to permit water to drain from the auxiliary float 13 and the main float 23 moves down to open the valve 3. As the tank fills, the auxiliary float 13 is lifted, water flows over the upper edges of the auxiliary float 13 and the main float 23 is lifted to close the valve 3.
Brandelli U.S. Pat. No. 4,094,327 discloses a telescoping liquid inlet conduit assembly that is adjustable to vary the liquid level in a tank. One conduit 32 has peripheral grooves 29. The other conduit 34 has one or more protrusions 27 that cooperate with grooves 29. Conduit 34 has axial slots permitting the conduit wall to flex. A snap fit end cap secures the conduits in a selected position.
Johnson U.S. Pat. No. 4,646,779 discloses an adjustable fill valve with a riser assembly with side by side inlet and outlet portions. A rotatable nut 44 accessible through opening 218 engages rack gear teeth 110 on inlet and outlet sections of a valve body 100. When the nut is rotated, the body is raised or lowered.
Johnson U.S. Pat. No. 3,895,645 and Shames et al. U.S. Pat. No. 4,562,859 disclose fill valves with valve disks with peripheral upwardly facing lip seals surrounding control chambers above the valve disks.
SUMMARY OF THE INVENTION
A primary object of this invention is to provide a fill valve that maintains a precise, repeatable and predictable water level in a tank such as a toilet tank. Other objects are to provide a fill valve permitting easy and precise water level adjustment without removing or disassembling the valve; to provide a fill valve with a valve disk sealing arrangement that maximizes disk flexibility while sealing against both positive and negative pressures in a control region above the disk; to provide a fill valve having a simplified and easily assembled control lever mounting arrangement; to provide a fill valve with a vacuum breaker for preventing back siphonage for a tank into a water supply; to provide a fill valve that is highly sensitive to water level changes in a standby condition yet operates abruptly from full open to full closed at the conclusion of a refill operation; and to provide a fill valve that overcomes problems encountered with known fill valves.
In brief, in accordance with the present invention there is provided a fill valve assembly for maintaining a liquid level in a tank including a liquid inlet conduit and a valve having an inlet communicating with the inlet conduit and an outlet communicating with the tank. A float chamber within the tank includes a bottom wall. A dam is spaced above the bottom wall permitting liquid communication between the tank and the float chamber when liquid level in the tank rises to the elevation of the dam. A float is mounted for floating movement between upper and lower positions within the float chamber. A lever connected between the float and the valve opens the valve in response to downward movement of the float and closes the valve in response to upward movement of the float. Means is provided for draining the float chamber when the liquid level in the tank is below the bottom wall. Means is also provided for providing a flow path in parallel flow relationship with the dam for permitting liquid communication between the tank and the float chamber when the float is in the upper position.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention and the above and other objects and advantages may best be understood from the following detailed description of the embodiment of the invention shown in the accompanying drawings, wherein:
FIG. 1 is a side elevational view of a fill valve constructed in accordance with the present invention;
FIG. 2 is a front elevational view of the fill valve, taken from the right side of the valve as viewed in FIG. 1, with a portion of the float chamber broken away;
FIG. 3 is an enlarged sectional view taken along the line 3--3 of FIG. 1;
FIG. 4 is an enlarged fragmentary elevational view taken from the line 4--4 of FIG. 1 with a portion broken away;
FIG. 5 is an enlarged fragmentary sectional view taken along the line 5--5 of FIG. 2;
FIG. 6 is a fragmentary sectional view taken along the line 6--6 of FIG. 5;
FIG. 7 is a sectional view taken along the line 7--7 of FIG. 5;
FIG. 8 is a sectional view taken along the line 8--8 of FIG. 5;
FIG. 9 is a fragmentary sectional view taken along the line 9--9 of FIG. 5;
FIG. 10 is a fragmentary sectional view taken along the line 10--10 of FIG. 5;
FIG. 11 is a fragmentary sectional view taken along the line 11--11 of FIG. 6;
FIG. 12 is an enlarged fragmentary sectional view taken along the line 12--12 of FIG. 8;
FIG. 13 is a view similar to a part of FIG. 5 showing portions of a float controlled valve and a check valve in alternate positions;
FIG. 14 is an enlarged view similar to a part of FIG. 5 showing the fill valve in an open position and showing the path of liquid flow through the fill valve;
FIG. 15 is a fragmentary sectional view taken along the line 15--15 of FIG. 14;
FIG. 16 is a fragmentary isometric view of the inner end of the control lever of the fill valve;
FIG. 17 is an exploded isometric view of components of the fill valve with portions broken away;
FIG. 18 is a greatly enlarged fragmentary sectional view of parts of the valve cup, valve disk and cap of the fill valve;
FIG. 19 is a partly schematic, simplified side elevational view of the fill valve of FIG. 1 installed in a tank and in a standby condition;
FIG. 20 is a view like FIG. 19 showing the fill valve near the beginning of a tank flush cycle;
FIG. 21 is a view like FIG. 20 showing the fill valve at a subsequent time following the flush cycle when the tank is being refilled; and
FIG. 22 is a view like FIG. 21 showing the fill valve near the end of the tank refill operation.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, there is illustrated a fill valve assembly generally designated by the reference character 24 and embodying the features of the present invention. The assembly 24 serves to control the level of liquid in a tank. A fragment of a bottom wall 26 of a tank with which the assembly 24 can be used is seen in FIGS. 19-22. For example, the tank may be the flush tank of a toilet. In this case, the assembly 24 maintains the level of water in the tank at a preselected level, and refills the tank to the preselected level after the tank is emptied for a flushing operation.
In general, the assembly 24 includes an adjustable riser assembly 28, a valve head portion 30 and a float assembly 32. A liquid inlet port 34 located at the bottom of the riser assembly 28 is adapted to be connected to a source of pressurized liquid such as a household water supply. Liquid outlet ports 36 disposed within the tank near the bottom of the riser portion 28 admit liquid to the interior of the tank when liquid flows through the head portion 30. When a decreasing liquid level is detected by a float 42, a control lever 38 pivots to bring about the movement of a main valve disk 40 from a closed position to an open position.
Riser assembly 28 includes a vertically extending support 100 and a supply tube 200 and body 300 movable relative to the support 100 for vertical adjustment of the head portion 30 and thereby of the level of liquid maintained in the tank. A cap 400 overlies the supply tube 200 and body 300 and cooperates with the valve disk 40 to define a valve control chamber 43 within the head portion 30. A cover 500 and a float chamber 600 enclose these components and also enclose the float 42 and the lever 38 of the float assembly 32. The elements of each structural component designated by a three digit reference character share the first digit in the subsequent detailed description.
Support 100 includes an inlet segment 102 terminating at inlet port 34 and having threads 104 for mating with a threaded retention nut 44 (FIGS. 17-21). To mount the assembly 24 in position upstanding from the tank bottom wall 26, a sealing gasket 46 is placed against an attached flange member 106 and the segment 102 is inserted through a hole in wall 26. Nut 44 is tightened in place to hold the support 100 with the inlet segment 102 projecting beyond the wall of the tank. A conventional fitting secured to threads 104 connects a water supply conduit (not shown) to the end of segment 102 to admit water under pressure to the inlet port 34.
Water entering the inlet port 34 flows through a strainer element 48 in order to remove particles and debris. Above the region of the filter element 48, the support 100 includes an inlet conduit portion 108 surrounded by a concentric outlet conduit portion 110. Portion 108 supplies water from the inlet segment 102 to the supply tube 200. Portion 110 directs water supplied from the head portion 30 to slots 112 located around the support 100 above the flange member 106 and terminating at outlet ports 36.
Screws 50 extending through the cover 500 and threaded into the body 300 hold the cap 400 and supply tube 200 in the assembled position best seen in FIG. 5. The supply tube 200 has a downwardly extending inlet conduit 202. The body 300 has a downwardly extending outlet conduit 302 surrounding and concentric with the inlet conduit 202. In order to permit vertical adjustment of the head portion 30 to select a desired tank water level, the conduits 202 and 302 are telescoped with and slidable relative to conduits 108 and 110 respectively. Thus, inlet conduit portion 108 and inlet conduit 202 cooperate to provide an inlet flow path of variable length. Similarly, the outlet conduit portion 110 and the outlet conduit 302 cooperate to provide an outlet flow path of simultaneously variable length. A sleeve 114 holds an O-ring seal 52 to provide sliding leak tight engagement between conduit portion 108 and inlet conduit 202. A labyrinth seal structure 120 minimizes flow down around the outside of the outlet conduit portion 110.
A desired water level in the tank can be precisely selected by moving the head portion 30 up or down within the tank. The selected adjustment is retained by a bayonet locking system that prevents unintentional movement of head portion 30 relative to the support 100 and tank bottom wall 26. As seen in FIGS. 3 and 4, four regularly spaced, upwardly facing lock flanges 304 are formed on the interior of the outlet conduit 302 near its end. Rows of downwardly facing lock teeth 116 are located at four locations around the outer surface of the support 100. Because the supply and outlet conduits are concentric, the head portion 30 can be rotated relative to the support 100. When the head portion is turned counterclockwise relative to the support 100, the flanges 304 are disengaged from the teeth 116 and the head portion may be freely raised and lowered. When the head portion is turned in the opposite direction, each flange 304 enters a space between adjacent teeth 116 and further vertical movement is prevented.
When a supply of pressurized water is connected to the inlet port 34, there is a pressure drop across the head portion 30. A typical household supply pressure in the range of forty-five to sixty pounds per square inch results in a force in the neighborhood of four pounds continuously urging the head portion in an upward direction. This force is used in the assembly 24 to provide a latching effect in the bayonet lock system. As seen in FIG. 4, the teeth 116 have axially extending detent projections 118 and the flanges 304 have cooperating detent recesses 306. In the locked position the supply pressure continuously forces the projections 118 into the recesses 306. This force must be overcome by the user to release the projections 118 from the recesses 306 before the head assembly can be rotated to move the flanges 302 from engagement with the teeth 116.
An enlarged upper section 204 of the supply tube 200 is captured between the cap 400 and the body 300. The upper end of the inlet conduit 202 terminates in an annular raised valve seat 206 engaged by the main valve disk 40 in its closed position seen in FIG. 6. A valve cup 54 includes an annular channel 54A in which the radially outer part of the main valve disk 40 is retained. Cup 54 also provides an annular valving surface 54B surrounding the valve seat 206. As seen in FIGS. 9 and 117, the surface 54B has radially extending flow ports 54C defined by slots extending from the inner periphery of the cup 54. Preferably the seat 206 projects slightly above the surface 54B to provide final shutoff of flow in the valve closed position. The cup 54 may be made of stamped sheet metal or molded plastic, and the flow ports may be of any desired size and shape.
The cap 400 (FIG. 5) includes a restrictor pin 402 projecting through a hole in a central hub 40A of the valve disk 40. As seen in FIG. 6, grooves in the pin 402 permit restricted flow from the inlet conduit 202 to the control chamber 43 above the valve disk 40. In the standby condition, pressurized water trapped in the region 43 biases the valve disk 40 down into its closed position against the valving surface 54B and seat 206. A pilot valve passage or orifice 404 extends from the control chamber 43 to the exterior of the cap 400. When the level in the tank drops below the selected level, lever 38 moves a resilient pilot valve seat 56 from the closed position (FIG. 5) to the open position (FIG. 14). Pressure within the control chamber drops and inlet pressure moves the valve disk to its open position. Water then flows from the inlet conduit, radially out across the valve seat 206 and downward through the flow ports 54C in the valving surface 54B.
Water flowing through the valve assembly 24 drops in pressure from supply pressure to atmospheric pressure within the tank. The path of flow of water through the assembly 24, indicated by arrows in FIG. 14, is designed to distribute this drop in pressure in order to achieve quiet operation and avoid cavitation. The first substantial drop in pressure occurs when water flows through the flow ports 54C into an annular inner chamber 208 in the inlet tube portion 204. The next pressure reduction occurs when water flows through ports 210 from the chamber 208 to an outer annular chamber 212. Preferably most of the pressure reduction occurs in these two stages. Because each of these pressure drops results from flow through relatively small ports into relatively large areas, the frequency of sound resulting from water flow is relatively high and the coupling of sonic energy back into the water supply system is reduced.
A peripheral lip 54D of the valve cup 54 cooperates with an upstanding annular flange 214 of the supply tube 200 to form an annular port through which water flows from the chamber 212 to a vacuum breaker chamber 406 defined within the cap 400. A vacuum breaker valve disk 58 is loosely contained in the chamber 406. Vent ports 408 extend from the chamber 406 to the region within the cover 500. Kinetic energy of water flowing up past the lip 54D moves the disk 58 up to close the vent ports 408. When water flow ceases, the disk drops from the vent ports in order to vent the flow path to atmosphere and prevent back siphonage of water from the tank through the fill valve assembly 24 to the water supply system.
A refill port 410 extends from the vacuum breaker chamber 408. A flexible tube (not shown) may extend from the port 410 to the toilet tank overflow pipe to reseal the trap in the fixture in accordance with known practice. Preferably about twenty percent of the total flow through the valve is diverted through the port 410 for refill of the trap.
Water flows from the vacuum breaker chamber 406 through an annular passage defined within an outer peripheral wall 216 of the supply tube 200. This annular passage leads to an annular cavity 308 defined in the upper portion of the body 300. From this cavity, water flows radially inward through an array of vanes 218 (FIG. 11) which impart a swirling motion to the flow of water as it enters the outlet conduit 302. The spinning motion in the outlet conduit stabilizes the flow and promotes complete purging of air from the flow path when the valve opens. Early purging of air has the advantage that the noise of bubbles is masked by the normal sounds of the flush cycle.
Valve disk 40 includes a flexible annular valving region 40B extending radially away from the central hub 40A. At the outer periphery of the disk 40 there is provided an axially extending rim portion 40C terminating at an enlarged bead portion 40D. The rim and bead 40C and 40D are received in the annular channel 54A of the valve cup 54. When the cap 400 is attached with screws 50, acting on the cover 500, a downwardly extending annular flange 412 is also received in the channel 54A. The bead 40D is captured between the cup 54 and the flange 412 and functions as a partial O-ring seal.
When the pilot orifice 404 is closed by the pilot seat 56, the control chamber above the valve disk 40 is pressurized at the water supply pressure and the surrounding vacuum breaker chamber 406 is at lower atmospheric pressure. Bead 40D seals this pressure within the control chamber. When the pilot orifice is opened and the valve disk 40 opens, the pressure in the control chamber drops to atmospheric pressure. There is a higher pressure in the vacuum breaker chamber 406 employed to supply the refill port 410. For example, the pressure reversal may in the area of ten pounds per square inch. The bead 40D, because it functions as an O-ring seal, is able to seal both positive and negative or this reverse pressure.
Because the enlarged bead 40D is provided on axial rim 40C rather than at the outer periphery of the valving region 40B, the sealing arrangement does not interfere with flexing of the region 40B. The valving region 40B can flex throughout its full radial extent. As a result, the valve disk 40 can be urged to its fully open position by a relatively small inlet pressure of only a few pounds per square inch.
Lever 38 is pivotally mounted between the cap 400 and the cover 500 without the need for a pivot shaft or pin. As seen in FIGS. 15 and 16, the lever is generally U-shaped in cross section. At an outer end the bight of the U is removed to leave the sides as spring arms 38A for attachment to the float 42. At an inner end, the lever includes a hole 38B for mounting of the pilot seat 56. At the location of the pivot axis, a pair of aligned slots 38C are formed at the intersection of the bight and the side walls of the U shape.
The cap 400 includes an upwardly extending fulcrum flange 414. A downwardly extending fulcrum flange 502 of the cover 500 is aligned with the flange 414. As seen in FIGS. 14 and 15, the bight of the U is retained between the flanges 414 and 502. There is sufficient clearance to permit the lever 38 to pivot between its alternate positions seen in FIGS. 5 and 14 around the pivot axis established by fulcrum flanges 414 and 502. A pair of shoulders 416 flanking the flange 414 are received in the slots 38C. Engagement between the shoulders 416 and the slots 38C retains the lever 38 in position by preventing longitudinal movement of the lever and by preventing shifting or pivoting in the plane of the bight of the U shape.
An outer rim 504 of the cover 500 mates with an upper rim 310 of body 300. A lower rim 312 of body 300 mates with an outer rim 602 of the float chamber 600. The bottom of the float chamber includes a sleeve 604 captured against support projections 314 near the top of the outlet conduit 302 of the body 300. A vent grid 506 permits free communication of atmospheric pressure to the interior region surrounded by the chamber 600, the body 300 and the cover 500. These elements form a protected location for the float assembly 32 and also suppress noise resulting from the flow of water through the assembly 24.
There are three paths for liquid communication between the interior of the float chamber 600 and the surrounding tank. One is by way of the sleeve 604. The upper edge of the sleeve 604 has a reduced height segment 605 extending between providing a pair of ribs having upper edges 606 located below the upper edge of the rest of the sleeve 604. Edges 606 thus act as weirs or dams. When water in the tank reaches the level of weirs 606, it spills over into the float chamber.
Another path for liquid communication is a port 608 in the bottom wall of the float chamber. A floating check ball 60 is held beneath port 608 by fingers 610 surrounded by a protective wall 612. When the water level in the tank is above the bottom wall of the float chamber 600, the ball floats and blocks the port 608. When water is present in the float chamber 600 and when the water level in the surrounding tank drops below the bottom of the float chamber, the floating ball check 60 drops from the port 608 and water can flow from the float chamber.
The third path for liquid to flow between the float chamber and the surrounding tank is provided by a float controlled port 614 in the bottom wall of the float chamber 600. Port 614 is defined by a tubular wall 616 extending above and below the chamber wall.
Float 42 includes a hollow, open bottom body 42A and an integral support arm 42B for suspending the float from the outer end of lever 38 within the float chamber 600. The upper end of the arm 42B includes projections received in openings in the spring arms 38A. Air trapped within the body 42A causes the float 42 to be buoyant upon the surface of water when water is present within the float chamber 600. Within the body 42A is a tubular stopper 42C that is aligned with the tubular wall 616 defining the port 614. Unequal conical tapers are formed on the interfacing ends of stopper 42C and wall 616 to guide the stopper into contact with the wall 616 as the water level in the tank falls (FIG. 13). The stopper 42C cooperates With the tubular wall 616 to function as a valve closing the port 614 when the float 42 is in its lowermost position within the float chamber 600.
Operation of the fill valve assembly may be understood with reference to the partly schematic illustrations in FIGS. 19-22 of sequential positions of components of the assembly during a toilet tank flush and refill cycle. In the standby mode of FIG. 19, the water level is maintained in the tank at the elevation identified by the reference character T. The float 42 is in its uppermost position and stopper 42C is spaced above the tubular wall 616 with the result that the float controlled port 614 is open. As a result the water level within the float chamber 600 is at the level designated by the reference character F and this elevation is the same as elevation T. The check ball 60 is submerged and its buoyancy holds it against the port 608.
Because the float chamber 600 and tank interior freely communicate in the standby condition by way of the port 614, the float 42 reacts quickly to any change of the tank water level. This sensitivity permits the valve assembly to make up for any small leakage from the tank that can occur because of normal flush valve seepage or the like. When the water level is at the selected position determined by adjusting the height of the head portion 30 and thus the elevation of the weirs 606, the float 42 and lever 38 hold the pilot seat 56 closed upon the pilot orifice 404. Small amounts of leakage can be replaced by pilot flow of water past the restrictor pin 402 and through the pilot orifice 404 when the float drops slightly, without cycling the main valve disk 40 open and closed. In addition, this sensitivity provides fast response of the valve assembly to the decreasing water level at the beginning of a flush cycle.
In FIG. 20 the beginning of a flush cycle is shown. When a flush cycle occurs, the tank is emptied rapidly into the fixture, and the water level within the tank drops abruptly. As seen in FIG. 20, the water level T in the tank and the water level F in the float chamber 600 have dropped to a level approaching the top of the tubular wall 616. The descending float 42 pulls the control lever 38 down and pivots the pilot seat 56 away from the pilot orifice 404. Pressure drops within the control chamber 43 above the valve disk 40 and the valve moves to the open position. Water begins flowing through the valve assembly 24 for refilling the tank. The flow into the tank through the assembly 24 is slower than the flow from the tank required to flush the fixture and the water level continues to drop until the flush cycle ends.
Until the float controlled port 614 is closed by the descending float stopper 42C, the water level decreases simultaneously inside and outside of the float chamber. Then for a brief interval the tank water level drops while the float chamber water level does not change. However, as soon as the tank water level drops below the bottom wall of the float chamber 600, the floating check ball 60 drops away from the port 608. This permits the remaining water to flow out of the float chamber into the tank, leaving the float chamber empty.
The water level in the tank continues to fall until the flush cycle is complete and the flush valve closes. Then the flow through the valve assembly 24 to the outlet ports 36 begins refilling the tank. At the same time, flow diverted through the refill port 410 reseals the trap in the fixture. FIG. 21 illustrates the tank water level T below the float chamber as the tank is being refilled. The rising water level is below the float chamber. The ball check port 608 is open and the float controlled port 614 is closed.
As the water level in the tank rises to the elevation of the bottom wall of the float chamber, the check ball floats against the port 608 and closes the port. Port 614 continues to be closed by the float stopper 42C. The weight of the float 42 overcomes the buoyant effect of water in the port 614. As a result, water rises around the float chamber while the float chamber remains empty. This condition is illustrated in FIG. 22. Although the tank water elevation T is well above the bottom of the float chamber, the ports 608 and 614 are closed and water cannot enter the float chamber. Because the float 42 stays in its lowermost position, the main valve disk 40 remains in its fully open position as the water level approaches the selected elevation.
When the rising water level reaches the level of weirs 606 plus the added height of a meniscus that initially prevents flow over the weirs 606, water rushes over the weirs 606 and rapidly fills the float chamber to the selected level. The surface area of water in the tank surrounding the float chamber 600 is larger than the area of the float chamber. Thus the water in the tank acts as a reservoir of immediately available water to fill the float chamber quickly. This causes the float 42 to rise abruptly from the lowermost position of FIG. 22 to the uppermost position of FIG. 19. The main valve disk 40 accordingly moves quickly from the fully open to the fully closed position and problems associated with slow closure and flow throttling are avoided.
The level of water in the tank is precisely adjusted by telescoping movement of the conduits 202 and 302 relative to the support 100. The level is selected without removing or disassembling the assembly 24 by pushing the head portion down against inlet water pressure to release the latch structures 118 and 306, turning the head portion relative to the support 100 to free the teeth 116 from the flanges 304 and raising or lowering the head portion 30 as desired. The water level is established by the elevation of weirs 606. A visual reference may be provided on the exterior of the float chamber 600 to aid the user in setting the water level. Once set, the telescoping parts are latched with the aid of inlet water pressure, and the level is repeated precisely during subsequent refills.
While the invention has been described with reference to details of the embodiments of the invention illustrated in the drawings, these details are not intended to limit the scope of the invention as set forth in the appended claims. | A fill valve assembly for a toilet tank or the like includes a riser and a head portion that can be vertically adjusted without removal or disassembly of the valve in order to select a precise tank liquid level. Telescoping conduits in the riser are secured in adjusted position by a bayonet latch system including detents assisted by the force applied by pressurized liquid at the inlet to the assembly. A main valve disk is held against a valve seat by pressure in a control chamber in a standby position and is moved to an open position by venting of the control chamber. The valve includes an axial peripheral flange having an enlarged bead portion captured in an annular channel to provide an O-ring type seal against positive and negative pressure while maximizing flexibility of the disk. A lever for controlling a pilot seat for venting the chamber is pivoted between fulcrum flanges and is held by shoulders abutting one of the flanges. The lever is pivoted by a float in a float chamber. A weir and a float controlled valve prevent entry of water into the float chamber in a refill cycle until tank liquid level reaches the selected level to be maintained. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application relates to the following commonly assigned applications entitled: “High-Speed Interconnection Adapter Having Automated Lane De-Skew,” Ser. No. 091596,980, filed Jun. 20, 2000, now U.S. Pat. No. 6,690,757, issued Feb. 10, 2004; and “High-Speed Interconnection Link Having Automated Lane Reordering,” Ser. No. 09/597,190, filed Jun. 20, 2000.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to high bandwidth interconnections for use in networking environments such as local area networks (LAN), wide area networks (WAN) and storage area networks (SAN). More specifically, it relates to a method of correcting inverted binary signals arising from crossing of differential pair signal carriers.
2. Description of Related Art
Internet and electronic commerce has grown to the point where demands placed on existing computer systems are severely testing the limits of system capacities. Microprocessor and peripheral device performances have improved to keep pace with emerging business and educational needs. For example, internal clock frequencies of microprocessors have increased dramatically, from less than 100 MHz to more than 1 GHz over a span of less than ten years. Where this performance increase in inadequate, high performance systems have been designed with multiple processors and clustered architecture. It is now commonplace for data and software applications to be distributed across clustered servers and separate networks. The demands created by these growing networks and increasing speeds are straining the capabilities of existing Input/Output (I/O) architecture.
Peripheral Component Interconnect (PCI), released in 1992, is perhaps the most widely used I/O technology today. PCI is a shared bus-based I/O architecture and is commonly applied as a means of coupling a host computer bus (front side bus) to various peripheral devices in the system. Publications that describe the PCI bus include the PCI Specification, Rev. 2.2, and Power Management Specification 1.1, all published by the PCI Special Interest Group. The principles taught in these documents are well known to those of ordinary skill in the art and are hereby incorporated herein by reference.
At the time of its inception, the total raw bandwidth of 133 MBps (32 bit, 33 MHz) provided by PCI was more than sufficient to sustain the existing hardware. Today, in addition to microprocessor and peripheral advancements, other I/O architectures such as Gigabit Ethernet, Fibre Channel, and Ultra3 SCSI are outperforming the PCI bus. Front side buses, which connect computer microprocessors to memory, are approaching 1-2 GBps bandwidths. It is apparent that the conventional PCI bus architecture is not keeping pace with the improvements of the surrounding hardware. The PCI bus is quickly becoming the bottleneck in computer networks.
In an effort to meet the increasing needs for I/O interconnect performance, a special workgroup led by Compaq Computer Corporation developed PCI-X as an enhancement over PCI. The PCI-X protocol enables 64-bit, 133 MHz performance for a total raw bandwidth that exceeds 1 GBps. While this is indeed an improvement over the existing PCI standard, it is expected that the PCI-X bus architecture will only satisfy I/O performance demands for another two or three years.
In addition to the sheer bandwidth limitations of the PCI bus, the shared parallel bus architecture used in PCI creates other limitations which affect its performance. Since the PCI bus is shared, there is a constant battle for resources between processors, memory, and peripheral devices. Devices must gain control of the PCI bus before any data transfer to and from that device can occur. Furthermore, to maintain signal integrity on a shared bus, bus lengths and clock rates must be kept down. Both of these requirements are counter to the fact that microprocessor speeds are going up and more and more peripheral components are being added to today's computer systems and networks.
Today, system vendors are decreasing distances between processors, memory controllers and memory to allow for increasing dock speeds on front end buses. The resulting microprocessor-memory complex is becoming more independent from other portions of the system. At the same time, there is a trend to move the huge amounts of data used in today's business place to storage locations external to network computers and servers. This segregation between processors and data storage has necessitated a transition to external I/O solutions.
One solution to this I/O problem has been proposed by the Infiniband(SM) Trade Association. The Infiniband(SM) Trade Association is an independent industry body that is developing a channel-based, switched-network-topology interconnect standard. This standard will de-couple the I/O subsystem from the microprocessor-memory complex by using I/O engines referred to as channels. These channels implement switched, point to point serial connections rather than the shared, load and store architecture used in parallel bus PCI connections.
The Infiniband interconnect standard offers several advantages. First, it uses a differential pair of serial signal carriers, which drastically reduces conductor count. Second, it has a switched topology that permits many more nodes which can be placed farther apart than a parallel bus. Since more nodes can be added, the interconnect network becomes more scalable than the parallel bus network. Furthermore, as new devices are added, the links connecting devices will fully support additional bandwidth. This Infiniband architecture will let network managers buy network systems in pieces, linking components together using long serial cables. As demands grow, the system can grow with those needs.
The trend towards using serial interconnections as a feasible solution to external I/O solutions is further evidenced by the emergence of the IEEE 1394 bus and Universal Serial Bus (USB) standards. USB ports, which allow users to add peripherals ranging from keyboards to biometrics units, have become a common feature in desktop and portable computer systems. USB is currently capable of up to 12 MBps bandwidths, while the IEEE 1394 bus is capable of up to 400 MBps speeds. A new version of the IEEE 1394 bus (IEEE 1394b) can support bandwidth in excess of 1 GBps.
Maintaining signal integrity is extremely important to minimize bit error rates (BER). At these kinds of bandwidths and transmission speeds, a host of complications which affect signal integrity may arise in the physical layer of a network protocol. The physical layer of a network protocol involves the actual media used to transmit the digital signals. For Infiniband, the physical media may be a twisted pair copper cable, a fiber optic cable, or a copper backplane. Interconnections using copper often carry the transmitted signals on one or more pairs of conductors or traces on a printed circuit board. Each optical fiber or differential conductor pair is hereafter called a “lane”.
Where multiple lanes are used to transmit serial binary signals, examples of potential problems include the reordering of the lanes and skew. Skew results from different lane lengths or impedances. Skew must be corrected so data that is transmitted at the same time across several lanes will arrive at the receiver at the same time. Lane reordering must be corrected so a digital signal may be reconstructed and decoded correctly at the receiver end.
Even in the simplest case involving a single differential wire pair, a potential problem exists in the routing of the differential wire pair. It is possible for wires to be crossed either inadvertently, as in a cable miswire, or intentionally, as may be necessary to minimize skew. In transmitting digital signals via a differential wire pair, one wire serves as a reference signal while the other wire transmits the binary signal. If the wire terminations are incorrect, the binary signal will be inverted.
Conventional correction and prevention of these types of problems has been implemented with the meticulous planning and design of signal paths. Differential wire pairs are typically incorporated into cables as twisted wire pairs of equal lengths. However, matched delay or matched length cabling is more expensive because of the manufacturing precision required. In backplane designs, trace lengths may vary because of board congestion, wire terminations and connector geometries. Shorter traces are often lengthened using intentional meandering when possible to correct for delay caused by other components. It is often impractical to correct crossed differential pairs because one trace passes through two vias to “cross under” the other trace. The vias introduce a substantial time delay, thereby causing data skew. Alternatively, the differential pairs are left uncorrected and the data inversion is accounted for using pin straps or boundary scan techniques. Both of these fixes require intervention by the system designer. These techniques have also been used to correct lane reversal.
The physical layer in Infiniband carries signals encoded by a digital transmission code called “8B/10B”. 8B/10B is an encoding/decoding scheme which converts an 8-bit word (i.e., a byte) at the link layer of the transport protocol to a 10-bit word that is transmitted in the physical layer of the same protocol.
The 8B/10B code is a “zero-DC” code, which provides some advantages for fiber optic and copper wire links. Transmitter level, receiver gain, and equalization are simplified and their precision is improved if the signals have a constant average power and no DC component. Simply stated, in converting an 8-bit word to a 10-bit word, the encoder selects the 10-bit representation based on the sign of the running disparity of the digital signal. Running disparity refers to a running tally of the difference between the number of 1 and 0 bits in a binary sequence. If the running disparity is negative (implying that more 0 bits have been transmitted than 1 bits), the subsequent 8B/10B word will contain more 1 bits than 0 bits to compensate for the negative running disparity. In the 8B/10B code, every 8-bit word has two 10-bit equivalent words. The 10-bit equivalent words will have five or more 1 bits for a negative running disparity and five or more 0 bits for a positive running disparity. For a more detailed description of the 8B10B code, refer to Widmer and Franaszek, “A DC-Balanced, Partitioned-Block, 8B/10B Transmission Code”, IBM J. Res. Develop., Vol. 27, No. 5, September 1983, which is hereby incorporated by reference.
The above design considerations clearly make physical layer (i.e., cables, backplanes) manufacturing a difficult venture in high clock frequency systems. Design costs and manufacturing costs are drastically increased due to the need to alleviate these types of problems. It is desirable, therefore, to provide a method of automatically correcting these types of errors with information embedded in the signals. It is further desirable to develop a method of automatically detecting and correcting inverted signals resulting from crossed differential signal pairs. This method of correction may advantageously allow for less stringent design requirements and could decrease design and manufacturing costs for high bandwidth data links.
BRIEF SUMMARY OF THE INVENTION
The problems noted above are solved in large part by an adapter configured to automatically detect and compensate for differential signal inversion. In one embodiment, the adapter is part of a computer network having differential conductor pairs conveying differential signals between network devices. The network devices include adapters coupled to transmit and receive signals via the differential conductor pairs. The adapter preferably includes a lane receiver, a decoder, and a synchronization circuit. The lane receiver is configured to receive a single differential signal and to convert the differential signal into a sequence of code symbols. The decoder decodes the code symbols to produce a sequence of received symbols. The synchronization circuit examines the sequence of received symbols to determine if it is incorrect due to inversion of the differential signal, and if so, it causes the lane receiver to correct for the differential signal inversion. It is expected that the received symbol sequence will include a training symbol sequence which will have a start symbol whose decoded value is unaffected by differential signal inversion, and a training symbol whose decoded value is indicative of the presence or absence of inversion. The synchronization circuit, upon identifying the training sequence, will thus be able to determine whether inversion exists and be able to automatically correct for it.
BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which:
FIG. 1 shows an illustrative diagram of a simple computer network which supports serial I/O connections;
FIG. 2 shows a functional block diagram of a simple computer network which supports serial I/O connections;
FIG. 3 shows a functional block diagram of an alternative computer network which supports serial I/O connections;
FIG. 4 shows a ladder diagram of the training sequence used to train ports that are coupled to opposite ends of a serial physical link;
FIG. 5 shows a table of the preferred training packets used to train ports that are coupled to opposite ends of a serial physical link;
FIG. 6 shows a table of the preferred lane identifiers used to label the individual channels in a serial physical link;
FIG. 7 shows a functional block diagram of a serial physical link; and
FIG. 8 shows a functional block diagram of an adapter configured to transmit and receive differential signals.
NOTATION AND NOMENCLATURE
Certain terms are used throughout the following description and claims to refer to particular system components. As one skilled in the art will appreciate, computer companies may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ”. Also, the term “couple” or “couples” is intended to mean either an indirect or direct electrical connection. Thus, if a first device couples to a second device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an example of a computer network representing a preferred embodiment, in which a central computer 100 is coupled to an external storage tower 110 and a network router 120 via a multiservice switch 130 . Storage tower 110 may be internally connected by a Fibre Channel, SCSI, or any suitable storage network. Network router may be connected to a LAN (local area network) or ISDN (Integrated Services Digital Network) network or it may provide a connection to the internet via a suitable ATM (asynchronous transfer mode) network. It should be appreciated that any number of computers, servers, switches, hubs, routers, or any suitable network device can be coupled to the network shown in FIG. 1 .
In the preferred embodiment shown in FIG. 1 , the devices are connected via a point to point serial link 140 . The serial link may comprise an even number of lanes or channels through which data is transmitted. Of the even number of lanes, half will transmit serial data in one direction while the other half transmits data in the opposite direction. In the preferred embodiment, the physical links will implement 1, 4, or 12 lanes in each direction. Thus, each link will have a total of 2, 8, or 24 total lanes.
In the latter two implementations (i.e., the 4 and 12 lane links), a single stream of bytes arriving at the input to the physical link are distributed evenly, or “striped”, among the multiple lanes. In the case of the 12-lane link, the first byte is sent to the first lane, the second byte is sent to the second lane and so on until the 12 th byte is sent to the 12 th lane. At that point, the byte distribution cycles back to the first lane and the process continues. Thus, over time, each lane will carry an equal {fraction (1/12)} th share of the bandwidth that the entire link carries. The same process and technique are used in the 4 lane link. Alternative embodiments with different numbers of lanes would preferably implement this striping process.
Once the bytes are distributed among the individual lanes, the 8-bit words are encoded into 10-bit words and transmitted through the physical link. At the output of the physical link, the 10-bit words are decoded back to 8-bit bytes and are re-ordered to form the original stream of 8-bit words.
FIG. 2 represents a functional block diagram of the computer network shown in FIG. 1 . The computer 100 generally includes a central processor unit (CPU) 202 , a main memory array 204 , and a bridge logic device 206 coupling the CPU 202 to the main memory 204 . The bridge logic device is sometimes referred to as a “North bridge” for no other reason than it often is depicted at the upper end of a computer system drawing. The North bridge 206 couples the CPU 202 and memory 204 to various peripheral devices in the system through a primary expansion bus (Host Bus) such as a Peripheral Component Interconnect (PCI) bus or some other suitable architecture.
The North bridge logic 206 also may provide an interface to an Accelerated Graphics Port (AGP) bus that supports a graphics controller 208 for driving the video display 210 . If the computer system 100 does not include an AGP bus, the graphics controller 208 may reside on the host bus.
Various peripheral devices that implement the host bus protocol may reside on the host bus. For example, a modem 216 , and network interface card (IC) 218 are shown coupled to the host bus in FIG. 2 . The modem 216 generally allows the computer to communicate with other computers or facsimile machines over a telephone line, an Integrated Services Digital Network (ISDN), or a cable television connection, and the NIC 218 permits communication between computers over a local area network (LAN) (e.g., an Ethernet network card or a Cardbus card). These components may be integrated into the motherboard or they may be plugged into expansion slots that are connected to the host bus.
FIG. 2 also depicts a host channel adapter (HCA) 220 connected to the host bus and target channel adapters (TCA) 230 , 240 connected to the external network devices 110 , 120 . These channel adapters generally provide address and translation capability for the switched topology architecture in the preferred embodiment. The channel adapters 220 , 230 , 240 preferably have dedicated IPv6 (Internet Protocol Version 6) addresses that can be recognized by the network switch 130 . As data is transmitted to the network, the source file is divided into packets of an efficient size for routing. Each of these packets is separately numbered and includes the address of the destination. When the packets have all arrived, they are reassembled into the original file. The network switch 130 in this preferred embodiment can detect the destination address, and route the data to the proper location.
FIG. 2 also shows the physical links 140 between the network devices as simple two lane links. In the embodiment shown in FIG. 2 , data would flow through one lane in one direction while data would flow through the parallel lane the other direction. As discussed above, alternative embodiments comprising any even number of lanes are also permissible, with 2, 8, and 24 lanes per link being the preferred number.
FIG. 3 shows an alternative embodiment of the computer network in which the computer 100 is replaced by a server 300 with a simple memory-processor architecture. Such a server may be part of a cluster of servers, a group of several servers that share work and may be able to back each other up if one server fails. In this particular embodiment, the server 300 is coupled to the switched-fabric network in much the same way the computer 100 of FIG. 1 is connected. The physical link 140 is connected to the server via a host channel adapter (HCA) 220 . However, in this embodiment, the HCA 220 is connected directly to a North Bridge 206 . Alternatively, the HCA 220 may be connected directly to a memory controller. In either event, a shared peripheral bus, such as a PCI bus, is not necessary in this embodiment. A peripheral bus may still be used in the server 300 , but is preferably not used to couple the north bridge 206 to the HCA 220 .
As discussed above, the serial data sent through the physical links is sent in the form of packets. The preferred embodiment uses the idea of packetized data and uses specialized packets called Training Set 1 and Training Set 2 to train the network devices prior to transmitting “real” data through the switched network. The actual content and structure of the training sets are discussed in further detail below.
FIG. 4 shows a link training ladder diagram describing the sequence of events during the training of ports located on either side of the physical link. In the preferred embodiment, a port refers to a transmitting and receiving device configured with a channel adapter to communicate via a serial link. In FIG. 4 , Port A 400 refers to one such device while Port B 410 refers to the device at the other end of the serial link.
The training data, TS 1 420 and TS 2 430 are packets of known data that are transmitted between Port A 400 and Port B 410 . The purpose behind the training sets are twofold. First, the initiation and duration of the training sequence is established by the transmission and reception of the training sets. Secondly, given that the training sets contain pre-determined data, the transmit and receive ports can use this knowledge to correct for any errors (e.g., data inversion, lane skew) that may result during transmission through the physical link. Since the errors are a constant, permanent result of routing in the physical media, the training sequence may be used to automatically correct the errors for all subsequent data transferred through that physical link.
FIG. 4 represents a time line for both Port A 400 and Port B 410 with time elapsing toward the bottom of the figure. Before training begins, Port A 400 may exist in an enabled state 440 while Port B is in a disabled or link down state 450 . By transmitting an initial sequence of TS 1 training sets 420 , Port A 400 can effectively wake up Port B 410 from a disabled state to an enabled state 440 . Once Port B is enabled 440 , two things occur. First, Port B 410 will begin transmitting TS 1 training sets back to Port A 400 . Secondly, Port B 410 will check the content of the incoming TS 1 training sets 420 to see if the data was received as it was sent. If there is any discrepancy, Port B 410 will correct the incoming signals so that the original content of TS 1 420 is restored. At this point, Port B 410 will be trained 460 and will respond by sending the second training set, TS 2 430 , back to Port A 400 .
Meanwhile, Port A 400 has been receiving TS 1 data 420 from Port B 410 and performs the same signal integrity checks and correction that Port B has completed. Once both ports are trained with TS 1 data 420 , the ports will proceed by sending TS 2 training data 430 . This second training set serves as a redundancy check to verify that the Ports were trained properly with TS 1 data 420 . In addition, the TS 2 data 430 signifies that both ports are trained and are ready to transmit and receive data packets 470 . Once a port is transmitting and receiving the TS 2 training sequence, it may begin sending data. With physical link errors corrected by the training sequences, the data packets 480 can then transmitted and received by the ports as intended.
In the event the training sequence fails, a timeout may occur and the affected port may be powered down or otherwise deactivated. Thus, when a transmission fault occurs, locating the problems in the physical link is facilitated by determining which port has been deactivated. By comparison, failure isolation in a bus architecture can he difficult because if one attached device fails, the entire system may fail. Discovering which device caused the failure is typically a hit-or-miss proposition.
FIG. 5 shows the actual format and content of the training sets TS 1 and TS 2 . In the preferred embodiment, each training set is 16 words long. It should be appreciated however, that training sets of different lengths are certainly possible. The width of the training set corresponds to the number of physical lanes in a training set. In the preferred embodiment, the training sets are 1, 4, or 12 words wide corresponding to the 1, 4, and 12 lanes in the preferred embodiment of the physical link. Certainly, other combinations of lane quantities are possible, but the width of the training set corresponds to the number of lanes in the physical link. The embodiment shown in FIG. 5 corresponds to a 4 lane link.
Each word in the training set is a 10-bit word that complies with the 8B/10B code discussed above. The first row (COM) in each column is a comma delimiter with a preferred code name K 28 . 5 . The second row in each column is a lane identifier that is unique to each lane in the physical link. A table of preferred lane identifiers is shown in FIG. 6 . In a single lane link, only lane identifier 0 is used. In a 4 lane link, lane identifiers 0, 1, 2, and 3 are used. In a 12 lane link, all twelve lane identifiers shown in FIG. 6 are used. After the lane identifier, the remaining 14 rows of the 16 row training sets are repeated 10-bit words. For training set l, the repeated word name is D 10 . 2 . For training set 2 , the repeated word name is D 5 . 2 .
The comma delimiter and lane identifiers are chosen to be insensitive to data inversion. That is, inverting a comma delimiter or a lane identifier symbol changes only the running disparity and not the symbol itself. Consider the 10-bit word for the comma delimiter K 28 . 5 . For a negative running disparity, the word is 001111 1010. For a positive running disparity, the word is 110000 0101. These two words are complements of each other. Inverting all the bits in the first word will yield the second word and vice-versa. Hence, regardless of whether or not a bit inversion has occurred in the physical link, when the receiver port decodes this word, the comma delimiter will result. The same is also true for each of the lane identifiers in FIG. 6 . For each lane identifier, the 10-bit words for negative running disparity are the complement of the 10-bit word for positive running disparity. Thus, a receiver will always know when a comma delimiter has arrived and which lane identifier corresponds to a given bit stream. The preferred code names selected for the comma delimiter and the lane identifiers were selected because of their inversion properties. Other code words exhibiting the same properties will also work in alternative embodiments.
To correct for a crossed differential pair (i.e., bit reversal in a lane), a receiver will decode the 10-bit words arriving in a particular bit stream and determine when the training data starts (as marked by the comma delimiter) and determine the lane number (as marked by the lane identifier). For training set 1 , the preferred 10-bit code name is D 10 . 2 and the bit sequence for positive running disparity is 010101 0101. The D 10 . 2 code word is chosen for the training set because it uses the exact same code word for negative running disparity as it does for positive running disparity. Thus, the receiver expects to receive the 010101 0101 sequence repeated 14 times for each training set 1 packet regardless of the current state of the running disparity. However, if the complementary code word is received (101010 1010), a completely different word is decoded. The inverted word corresponds to the D 21 . 5 code word. If the receiver decodes this inverse word, the decoder will be configured to invert all the subsequent bits received in that particular lane.
The same conditions hold true for training set number 2 . For training set 2 , the preferred 10-bit code name is D 5 . 2 and the bit sequence for both positive and negative running disparity is 101001 0101. The inverted code word (010110 1010) corresponds to code name D 26 . 5 . Again, the receiving port will attempt to recover the correct polarity by inverting a bit stream if the D 26 . 5 code words are received. The preferred code names selected for training set 1 and training set 2 were selected because of their inversion properties. Other code words exhibiting the same properties will also work in alternative embodiments.
FIG. 7 shows a block diagram of a preferred embodiment of a serial physical link. Included in the link are Port A 400 and Port B 410 as discussed above. The link shown in FIG. 7 is a 2-lane link with one lane configured to transmit in one direction and the other lane configured to transmit in the opposite direction. Included in the link are retimers 700 , 710 located at opposite ends of the link. Retimers 700 , 710 provide a means of compensating for minor clock tolerances that result in different clock rates between Port A 400 and Port B 410 . To compensate for these clock differences, a data packet called a SKIP ordered set 720 is transmitted at regular intervals amidst the training, data, or idle data packets. In the preferred embodiment, the SKIP ordered sets 720 are inserted every 4608 symbol clocks and include a COM delimiter followed by three SKIP words. As with the training sets, the SKIP ordered sets 720 are as wide as the number of lanes in the link. In FIG. 7 , the link contains only one lane, so the SKIP ordered sets 720 , contain only one column of 10-bit words.
If a delay is needed to compensate for advanced clock timing, the retimers 700 , 710 may insert an additional SKIP word to delay the arrival of subsequent data at the receiving end of the link. This scenario is depicted by the SKIP ordered set 740 shown at the receiver of Port B 410 . SKIP ordered set 740 includes two additional SKIP words that have been added by retimer 700 and retimer 710 . Consequently, a SKIP ordered set that started with three SKIP words now has a total of five SKIP words. Conversely, if an advance is needed to compensate for delayed clock timing, the retimers 700 , 710 may remove an existing SKIP word to advance the arrival of subsequent data at the receiving end of the link. SKIP ordered set 730 shows an example of this scenario SKIP ordered set 730 contains only one SKIP word as a result of the removal of one SKIP word each by retimer 700 and retimer 710 . By compensating for clock tolerances, the link and the Ports on either end of the link can operate in a common clock domain.
In the preferred embodiment, the SKIP word name is K 28 . 0 and the associated 10-bit word is 001111 0100 for negative running disparity and 110000 1011 for positive running disparity. As is the case with the CAM and lane identifier words, the SKIP word is insensitive to bit inversion. Other code words exhibiting the same property will also work in alternative embodiments.
FIG. 8 shows a block diagram of an adapter 800 configured to convert signals transmitted to and received from a physical link 820 . The adapter may be coupled to or otherwise form a part of a port and/or a channel adapter. The adapter 800 is coupled to differential wires or traces 810 in the physical link. Differential signals received from the physical link 820 are detected by a lane receiver 830 (referred to as “LR”) that converts the differential signals to a bit stream that is sent to a 10B/8B decoder 850 . The decoder converts the 10 bit words received from the individual lanes into 8 bit words that are directed to the FIFO buffers 870 . In an alternative embodiment, the FIFO buffers 870 may precede the 10B/8B decoders. After the 10B/8B decoders and FIFO buffers, the 8-bit words are synchronously clocked into a multiplexer or other suitable logic device 880 to reconstruct a single byte stream from the individual byte streams. The byte stream is then sent to a local interface 805 for transmission to the local device 815 .
The adapter 800 may also convert signals for transmission to a physical link 820 . A byte stream from a local device 815 is detected and transmitted to a demultiplexer 890 that stripes bytes from the single byte stream across a number of individual byte streams. FIG. 8 depicts four lanes in the physical link, but this quantity may be different and may depend on whether the link is coupled to a single channel adapter. The individual byte streams are then coded by the 8B/10B encoders 860 and the resulting bit streams are delivered to lane adapters 840 (referred to as “LA”) which convert the bit streams to differential signals for transmission across wire pairs or traces 810 in the physical link 820 .
The above discussion is meant to be illustrative of the principles and various embodiments of the present invention. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. For example, a physical link with the above properties and characteristics may be constructed with eight or sixteen lanes per link and still operate within the scope of this description. It is intended that the following claims be interpreted to embrace all such variations and modifications. | An adapter configured to automatically detect and compensate for differential signal inversion is herein disclosed. In one embodiment, the adapter is part of a computer network having differential conductor pairs conveying differential signals between network devices. The network devices include adapters coupled to transmit and receive signals via the differential conductor pairs. The adapter preferably includes a lane receiver, a decoder, and a synchronization circuit. The lane receiver is configured to receive a single differential signal and to convert the differential signal into a sequence of code symbols. The decoder decodes the code symbols to produce a sequence of received symbols. The synchronization circuit examines the sequence of received symbols to determine if it is incorrect due to inversion of the differential signal, and if so, it causes the lane receiver to correct for the differential signal inversion. It is expected that the received symbol sequence will include a training symbol sequence which will have a start symbol whose decoded value is unaffected by differential signal inversion, and a training symbol whose decoded value is indicative of the presence or absence of invasion. The synchronization circuit, upon identifying the training sequence, will thus be able to determine whether inversion exists and be able to automatically correct for it. | 7 |
FIELD OF THE INVENTION
[0001] This present invention relates to an aromatic heterocyclic substituted acardite derivate and application thereof In addition, the present invention relates to application of aromatic heterocyclic substituted acardite derivate and pharmaceutically acceptable salts thereof in the treatment of tumor or leukemia.
BACKGROUND OF THE INVENTION
[0002] With better understanding of the tumor molecular mechanisms, the research on the targeted therapy of the tumor moleculars has achieved important advance. Protein kinase inhibitor is one of newly developed targeted therapy drugs, which affects the survival, proliferation and disease progression of tumor cells through blocking the intra-cellular molecular transduction pathway. Raf kinases play a crucial role in the signal transduction pathway of Raf/MEK/ERK. Although the function of the Raf kinase in normal tissues is not yet understood, but the existing basic and clinical research results have shown that the upregulation of Raf gene and overexpression of its protein are present in various solid tumors, including renal cell carcinoma, hepatocellular carcinoma, melanoma and non-small cell lung cancer. Currently, more and more single target point and multi-target point therapy drugs for Raf kinases are successfully developed and applied clinically, for example, sorafenib and erlotinib have achieved good clinical results, and the anti-tumor therapy has came into the “molecular targeted therapy” era. CN200810129360.6 disclosed that a kind of aromatic heterocyclic substituted acardite derivates with no substituent or only carbamyl in the A ring have prospect of inhibiting specific tumors, and the preliminary pharmacological experiments found that the effects of some compouns are better than sorafenib.
SUMMARY OF THE INVENTION
[0003] The objective of the present invention is to provide an aromatic heterocyclic substituted acardite derivate having more medicinal value through structural modification based on the existing technology. After the present invention adds specific substituents in the A ring, especially adding substituents in the quinazoline, pyrrole or pyrimidine rings, the inhibitory activity and selectivity of the compounds to specific tumors are greatly increased, and the absorptivity and utilization rate of the compounds are increased and the toxic side effects are reduced. The objective of the present invention is further to provide application of the compound or pharmaceutically acceptable salts thereof in the treatment of tumor or leukemia. The heterocyclic substituted acardite derivate of the present invention can be represented by the following formulas [1] and [2]:
[0000]
wherein,
[0005] A is monosubstituted or polysubstituted quinoline, isoquinoline, quinazoline, pyrrole or pyrimidine, preferably monosubstituted or polysubstituted quinazoline, pyrrole or pyrimidine, further preferably monosubstituted or polysubstituted quinazoline; the substituent is halogen, alkyl, haloalkyl, alkoxy, haloalkoxy, alkylamino, haloalkylamino, amino or nitryl, preferably halogen, C 1-5 alkyl, C 1-5 haloalkyl, C 1-5 alkoxy, C 1-5 haloalkoxy, C 1-5 alkylamino, C 1-5 haloalkylamino, amino or nitryl, more preferably halogen, C 1-5 alkyl, C 1-5 haloalkyl, C 1-5 alkoxy, C 1-5 haloalkoxy, amino or nitryl; still more preferably halogen, amino, C 1-5 alkyl or C 1-3 alkoxy, particularly preferably Cl, Br, F, amino, methoxy, methyl, ethyl, propyl, isopropyl, butyl or t-butyl in the present invention.
[0006] R 1 is alkyl, more preferably C 1-5 alkyl, most preferably methyl, ethyl, propyl and isopropyl.
[0007] R 2 is one or more selected from hydrogen, halogen, alkyl, alkoxy, haloalkyl or haloalkoxy; preferably one or more selected from hydrogen, halogen, C 1-5 alkyl, C 1-5 alkoxy, C 1-5 haloalkyl or C 1-5 haloalkoxy, most preferably one or more selected from H, Cl, Br, F, methoxy, ethoxy, propoxy, methyl, ethyl, propyl, isopropyl, butyl, t-butyl or trifluoromethyl.
[0008] R 3 is one or more selected from hydrogen, halogen, alkyl, alkoxy, C 1-5 haloalkyl or C 1-5 haloalkoxy, preferably one or more selected from hydrogen, halogen, C 1-5 alkyl, C 1-5 alkoxy, C 1-5 haloalkyl or C 1-5 haloalkoxy, most preferably one or more selected from H, Cl, Br, F, methoxy, ethoxy, propoxy, methyl, ethyl, propyl, isopropyl, butyl, t-butyl or trifluoromethyl.
[0009] The pharmaceutically acceptable salts of the compound in the present invention are selected from:
a) basic salts of inorganic acids and organic acids, the described acid is selected from hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, mesylate, trifluoromethanesulfonic acid, benzene sulfonic acid, paratoluenesulfonic acid, 1-naphthalene sulfonic acid, 2-naphthalene sulfonic acid, acetic acid, trifluoroacetic acid, malic acid, tartaric acid, citric acid, lactic acid, oxalic acid, succinic acid, fumaric acid, maleic acid, benzoic acid, salicylic acid, phenylacetic acid or almonds acid; b) acid salts of organic and inorganic base, the described cation is selected from alkali metal cation, alkaline earth metal cation, ammonium cation, aliphatic-substituted ammonium cation or aromatic-substituted ammonium cation.
Preparation of the Compound of Formula 1
[0012] Method 1: the target compound is obtained from substituted heterocyclic 2-carboxylate as starting materials through acyl chlorination, aminoalkylation, two-step condensation and salt forming reaction and the route is as follows:
[0000]
[0013] Method 2: the target compound is obtained from substituted heterocyclic 2-carboxylate as starting materials through acyl chlorination, aminoalkylation, condensation and salt forming reaction and the route is as follows:
[0000]
Preparation of the Compound of Formula 2
[0014] The target compound is obtained from halogen substituted heterocyclic as starting materials through two-step condensation and salt forming reaction and the route is as follows:
[0000]
[0015] The substituents A, R 1 , R 2 and R 3 in the above menthioned reaction routes have the above described meanings.
[0016] The beneficial effects of the present invention are as follows:
[0017] The derivatives of the present invention have raf kinase inhibitory activity. The action mechanism of this compound is that this compound affects the survival, proliferation and disease progression of tumor cells through inhibiting raf kinase and blocking the ras protein signal transduction connection, thereby inhibiting the growth of achiblastomas, such as malignant tumors (for example, bladder cancer, lung cancer, pancreatic cancer), myelopathy (for example, myelogenous leukemia) or adenoma (for example, villous adenoma of colon).
[0018] The experiment results have shown that the compound with special substituents added in A ring in the present invention has stronger antitumor activity compared with the previously disclosed compound with no substituent or only carbamyl in A ring, which is obviously stronger than Sorafenib in the effects of tumor cell metastasis and tumor angiogenesis. The test on normal human umbilical vein endothelial cells found that this part of the compounds have lower toxicity to normal human cells, such as endothelial cell, which are safe and reliable, but which can inhibit the tumor angiogenesis to achieve anti-tumor activity. In vivo nude mice transplanted model experiment proved that the compound of the present invention has inhibitory effects to human liver and kidney cancer and the effects are stronger than Sorafenib, which has more obvious effects on lung cancer and the effects are significantly better than the positive control drug Sorafenib. The results show that the compound of the present invention or pharmaceutically acceptable salts thereof can be used in the drugs for the treatment of cancer or leukemia, particularly drugs used for treating lung cancer.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The melting point was measured by the electric melting point instrument and the thermometer was not corrected; the elemental analyzer was Foss-Heraeus type; and the mass spectrograph was electrospray ionization mass spectrometry.
[0020] A: preparing the aromatic heterocyclic substituted acardite derivate having the general formula 1 accroding to method 1
[0000]
Embodiment 1
Preparation of 4-Chloro-6-Methoxyquinolinyl-2-Carbonyl Chloride
[0021] 50g of 4-hydroxy-6-methoxy-2-quinolinecarboxylic acid and 100 m1 of thionyl chloride were added into a three-necked flask, heated and refluxed for 17 hours until the reaction finished. The filtrate was added with toluene and concentrated under vacuum to obtain yellow solid, namely 4-chloro-6-methoxyquinolinyl-2-carbonyl chloride, with dry weight of 50g.
Embodiment 2
Preparation of 4-Chloro-7-Fluoroquinazolinyl-2-Carbonyl Chloride
[0022] Prepared from 4-hydroxy-7-fluoro-2-quinazolinecarboxylic acid with reference to the method of embodiment 1.
Embodiment 3
Preparation of 4-Methoxy-5-Chloropyrimidine-2-Carbonyl Chloride
[0023] Prepared from 4-methoxy-5-hydroxy-2-pyrimidinecarboxylic acid with reference to the method of embodiment 1.
Embodiment 4
Preparation of 4-Chloro-7-Amino-Isoquinolyl-2-Carbonyl Chloride
[0024] Prepared from 4-hydroxy-7-amino-2-quinazolinecarboxylic acid with reference to the method of embodiment 1.
Embodiment 5
Preparation of 5-Methyl-4-Chloropyrrolyl-2-Carbonyl Chloride
[0025] Prepared from 5-methyl-4-hydroxy-2-pyrrolecarboxylic acid with reference to the method of embodiment 1.
Embodiment 6
Preparation of 4-Chloro-6-Methoxyl-N-methyl-2-Quinolinyl Formamide
[0026] 10 g of 4-chloro-6-methoxyquinolinyl-2-carbonyl chloride (obtained from embodiment 1) was reacted with 200 ml of 2M methylamine ethanol solution under 0° C. for 36 hours until the reaction finished. The solvent was evaporated under vacuum and the residues were added with water followed by stirring evenly. Ethyl acetate was added for extracting and the ethyl acetate layer was dried with anhydrous sodium sulfate. The ethyl acetate layer was removed under vacuum to obtain 9 g of 4-chloro-6-methoxy-N-methyl-2-quinoline carboxamide.
Embodiment 7
Preparation of 4-Chloro-7-Fluoro-N-Methyl-2-Quinazoline Methanamide
[0027] Prepared from 4-chloro-7-fluoroquinazolinyl-2-carbonyl chloride with reference to the method of embodiment 6.
Embodiment 8
Preparation of 4-Methoxyl-5-Chloro-N-Methyl-2-Pyrimidinecarboxamide
[0028] Prepared from 4-methoxyl-5-chloropyrimidinyl-2-carbonyl chloride with reference to the method of Embodiment 6.
Embodiment 9
Preparation of 4-Chloro-7-Amino-N-Methyl-2-Isoquinolinecarboxamide
[0029] Prepared from 4-chloro-7-aminoisoquinolyl-2-carbonyl chloride with reference to the method of embodiment 6.
Embodiment 10
Preparation of 5-Methyl-4-Chloro-N-Methyl-2-Pyrrole Carboxamide
[0030] Prepared from 5-methyl-4-chloropyrryl-2-carbonyl chloride with reference to the method of embodiment 6.
Embodiment 11
Preparation of
[0031] 4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquinolinyl) oxy))aniline 10 g of 4-chloro-6-methoxyl-N-methyl-2-quinoline carboxamide (obtained from embodiment 6) was dissolved in DMF, added with 20 g of potassium tert-butylate and 10 g of 4-aminophenol and kept at 70° C. under the protection of nitrogen for 8 hours. After the reaction finished, the reaction solution was poured into 250 ml of ethyl acetate and 250 ml of saturated saline solution and stirred evenly for separation. The water solution was extracted with ethyl acetate again. The ethyl acetate layer was washed with saturated saline solution and dried with anhydrous sodium sulfate. The solvent was evaporated and removed under vacuum to obtain 6 g of 4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquinolinyl)oxy))aniline.
Embodiment 12
Preparation of 4-(2-(N-Methylaminoformoxyl)-4-(7Fluoroquinazolinyl) Oxy)Aniline
[0032] Prepared from 4-chloro-7-fluoro-N-methyl-2-quinazoline methanamide with reference to the method of embodiment 11.
Embodiment 13
Preparation of
[0033] 4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyrimidinyl) oxy)aniline Prepared from 4-methoxyl-5-chloro-N-methyl-2-pyrimidinecarboxamide with reference to the method of embodiment 11.
Embodiment 14
Preparation of 4-(2-(N-Methylaminoformoxyl)-4-(7-Amino-Isoquinolyl) Oxy)Aniline
[0034] Prepared from 4-chloro-7-amino-N-methyl-2-isoquinolinecarboxamide with reference to the method of embodiment 11.
Embodiment 15
Preparation of 4-(2-(N-Methylaminoformoxyl)-4-(5-Methyl-Pyrryl)Oxy) Aniline
[0035] Prepared from 5-methyl-4-chloro-N-methyl-2-pyrrole carboxamide with reference to the method of embodiment 11.
Embodiment 16
Synthesis of 4-Chloro-3-(Trifluoromethyl)Phenyl Isocyanate
[0036] 20 g of 4-chloro-3-(trifluoromethyl)aniline was mixed with 100 ml benzene, added with 20g of diphosgene and refluxed for 12 hours. The reaction solution was added with toluene, and the solvent was evaporated and removed under vacuum to obtain the product 4-chloro-3-(trifluoromethyl)phenyl isocyanate.
Embodiment 17
Synthesis of 4-Bromo-3-(Trifluoromethyl)Phenyl Isocyanate
[0037] Prepared from 4-bromo-3-(trifluoromethyl)aniline with reference to the method of embodiment 16.
Embodiment 18
Synthesis of 4-Fluoro-3-(Trifluoromethyl)Phenyl Isocyanate
[0038] Prepared from 4-fluoro-3-(trifluoromethyl)aniline with reference to the method of embodiment 16.
Embodiment 19
Synthesis of Compound 1
[0039] 7 g of 4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquinolinyl)oxy))aniline (obtained from embodiment 11), 5 g of 4-chloro-3-(trifluoromethyl)phenyl isocyanate (obtained from embodiment 16) and 50 ml of methylene dichloride were stirred at room temperature for 24 hours, and the crystals were separated out followed by air pump filtration and collection to obtain
[0040] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea.
Embodiment 20
Synthesis of Compound 2
[0041] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea was prepared from
[0042] 4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquinolinyl) oxy))anilineaniline and
[0043] 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 21
Synthesis of Compound 3
[0044] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquin olinyl)oxy))phenyl)urea was prepared from
[0045] 4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquinolinyl)oxy))aniline and
[0046] 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 22
Synthesis of Compound 4
[0047] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazol inyl)oxy) phenyl)urea was prepared from
[0048] 4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazolinyl)oxy)aniline (obtained from embodiment 12) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 23
Synthesis of Compound 5
[0049] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazoli nyl)oxy) phenyl)urea was prepared from
[0050] 4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazolinyl)oxy)aniline and
[0051] 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 24
Synthesis of Compound 6
[0052] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazol inyl)oxy) phenyl)urea was prepared from
[0053] 4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazolinyl)oxy)aniline and
[0054] 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 25
Synthesis of Compound 7
[0055] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyri midinyl)oxy) phenyl)urea was prepared from
[0056] 4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyrimidinyl)oxy)aniline (obtained from embodiment 13) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 26
Synthesis of Compound 8
[0057] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyrim idinyl)oxy) phenyl)urea was prepared from
[0058] 4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyrimidinyl)oxy)aniline and
[0059] 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 27
Synthesis of Compound 9
[0060] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyri midinyl)oxy) phenyl)urea was prepared from
[0061] 4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyrimidinyl)oxy)aniline and
[0062] 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 28
Synthesis of Compound 10
[0063] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7-amino-isoquin olyl)oxy)phenyl)urea was prepared from
[0064] 4-(2-(N-methylaminoformoxyl)-4-(7-amino-isoquinolyl)oxy)aniline (obtained from embodiment 14) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 29
Synthesis of Compound 11
[0065] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7-amino-isoquin olyl)oxy)phenyl)urea was prepared from
[0066] 4-(2-(N-methylaminoformoxyl)-4-isoquinolyl)oxy)aniline and
[0067] 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 30
Synthesis of Compound 12
[0068] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7-amino-isoqui nolyl)oxy)phenyl)urea was prepared from
[0069] 4-(2-(N-methylaminoformoxyl)-4-isoquinolyl)oxy)aniline and
[0070] 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 31
Synthesis of Compound 13
[0071] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(5-methyl-pyrryl) oxy)phenyl)urea was prepared from
[0072] 4-(2-(N-methylaminoformoxyl)-4-(5-methyl-pyrryl)oxy)aniline (obtained from embodiment 15) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 32
Synthesis of Compound 14
[0073] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(5-methyl-pyrryl) oxy)phenyl)urea was prepared from
[0074] 4-(2-(N-methylaminoformoxyl)-4-(5-methyl-pyrryl)oxy)aniline and
[0075] 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 33
Synthesis of Compound 15
[0076] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(5-methyl-pyrryl) oxy)phenyl)urea was prepared from
[0077] 4-(2-(N-methylaminoformoxyl)-4-(5-methyl-pyrryl)oxy)aniline and
[0078] 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 19.
Embodiment 34
Synthesis of
[0079] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea mesylate
[0080] 10 g of
[0081] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea free base was dissolved in 300 ml of ether and added with methanesulfonic acid/ethanol solution in drops at room temperature until pH=2, and white crystal was precipitated followed by air pump filtration and collection to obtain
[0082] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea mesylate.
Embodiment 35
Synthesis of Pharmaceutically Acceptable Salts of
[0083] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquin olinyl)oxy))phenyl)urea
[0084] With reference to the method of embodiment 34, fluoromethanesulfonic acid/ethanol solution, benzene sulfonic acid/ethanol solution, p-toluenesulfonic acid/ethanol solution,
[0085] 1-naphthalenesulfonic acid/ethanol solution, 2-naphthalenesulfonic acid/ethanol solution, acetic acid/ethanol solution, trifluoroacetic acid/ethanol solution, malic acid/ethanol solution, tartaric acid/ethanol solution, citric acid/ethanol solution, lactic acid/ethanol solution, oxalic acid/ethanol solution, succinic acid/ethanol solution, fumaric acid/ethanol solution, maleic acid/ethanol solution, benzoic acid/ethanol solution, salicylic acid/ethanol solution, phenylacetic acid/ethanol solution or mandelic acid/ethanol solution were added in drops to synthesize trifluoromethylsulfonate, benzene sulfonate, tosilate, 1-naphthalenesulfenesulfonate, 2-naphthalenesulfenesulfonate, acetate, trifluoroactate, malate, tartrate, citrate, lactate, oxalate, succinate, fumarate, maleate, benzoate, salicylate, phenylacetate or mandelate of N-(4-chloro-3 -(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea.
[0086] The pharmaceutically acceptable salts of compounds 2-15 can be also synthesized according to the above mentioned method.
[0087] B: preparing the aromatic heterocyclic substituted acardite derivate having the general formula 1 accroding to method 2
[0000]
Embodiment 36
Synthesis of
[0088] N-(4-chloro-3 -(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea
[0089] 20 g of 4-chloro-3-(trifluoromethyl)phenyl isocyanate (obtained from embodiment 16), 15 g of 4-aminophenol and 500 ml of dichloromethane were stirred at room temperature for 2 h, and the crystal was precipitated, followed by air pump filtration and collection, washing with dichloromethane and vacuum drying to obtain
[0090] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea.
Embodiment 37
Synthesis of
[0091] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea
[0092] Prepared from 4-bromo-3-(trifluoromethyl)phenyl isocyanate (obtained from embodiment 17) with reference to embodiment 36.
Embodiment 38
Synthesis of
[0093] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea
[0094] Prepared from 4-fluoro-3-(trifluoromethyl)phenyl isocyanate (obtained from embodiment 18) with reference to embodiment 36.
Embodiment 39
Synthesis of
[0095] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea (compound 1)
[0096] 10 g of N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea (obtained from embodiment 36), 8.2 g of 4-chloro-6-methoxyl-N-methyl-2-quinoline carboxamide (obtained from embodiment 6) and 50 ml dichloromethane were stirred at room temperature for 24 h, and the crystal was precipitated, followed by air pump filtration and collection to obtain 12 g of N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea.
Embodiment 40
Synthesis of Compound 2
[0097] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquino linyl)oxy))phenyl)urea was prepared from
[0098] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0099] 4-chloro-6-methoxyl-N-methyl-2-quinoline carboxamide according to the method of Embodiment 39.
Embodiment 41
Synthesis of Compound 3
[0100] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(6-methoxyquin olinyl)oxy))phenyl)urea was prepared from
[0101] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0102] 4-chloro-6-methoxyl-N-methyl-2-quinoline carboxamide according to the method of Embodiment 39.
Embodiment 42
Synthesis of Compound 4
[0103] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazol inyl)oxy) phenyl)urea was prepared from
[0104] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0105] 4-chloro-7-fluoro-N-methyl-2-quinazoline methanamide (obtained from embodiment 7) according to the method of Embodiment 39.
Embodiment 43
Synthesis of Compound 5
[0106] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazoli nyl)oxy)phenyl)urea was prepared from
[0107] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0108] 4-chloro-7-fluoro-N-methyl-2-quinazoline methanamide according to the method of Embodiment 39.
Embodiment 44
Synthesis of Compound 6
[0109] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7fluoroquinazol inyl)oxy)phenyl)urea was prepared from
[0110] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0111] 4-chloro-7-fluoro-N-methyl-2-quinazoline methanamide according to the method of Embodiment 39.
Embodiment 45
Synthesis of Compound 7
[0112] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyri midinyl)oxy) phenyl)urea was prepared from
[0113] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0114] 4-methoxyl-5-chloro-N-methyl-2-pyrimidinecarboxamide (obtained from embodiment 8) according to the method of Embodiment 39.
Embodiment 46
Synthesis of Compound 8
[0115] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyrim idinyl)oxy)phenyl)urea was prepared from
[0116] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and 4-methoxyl-5-chloro-N-methyl-2-pyrimidinecarboxamide according to the method of Embodiment 39.
Embodiment 47
Synthesis of Compound 9
[0117] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-5-(4-methoxypyri midinyl)oxy)phenyl)urea was prepared from
[0118] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0119] 4-chloro-N-methyl-2-pyrimidinecarboxamide according to the method of Embodiment 39.
Embodiment 48
Synthesis of Compound 10
[0120] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7-amino-isoquin olyl)oxy)phenyl)urea was prepared from
[0121] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0122] 4-chloro-7-amino-N-methyl-2-isoquinolinecarboxamide (obtained from embodiment 9) according to the method of Embodiment 39.
Embodiment 49
Synthesis of Compound 11
[0123] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7-amino-isoquin olyl)oxy)phenyl)urea was prepared from
[0124] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0125] 4-chloro-7-amino-N-methyl-2-isoquinolinecarboxamide according to the method of Embodiment 39.
Embodiment 50
Synthesis of Compound 12
[0126] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(7-amino-isoqui nolyl)oxy)phenyl)urea was prepared from
[0127] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0128] 4-chloro-7-amino-N-methyl-2-isoquinolinecarboxamide according to the method of Embodiment 39.
Embodiment 51
Synthesis of Compound 13
[0129] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(2-methyl-pyrryl) oxy)phenyl)urea was prepared from
[0130] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0131] 2-methyl-4-chloro-N-methyl-2-pyrrole carboxamide (prepared from embodiment 10) according to the method of Embodiment 39.
Embodiment 52
Synthesis of Compound 14
[0132] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(2-methyl-pyrryl) oxy)phenyl)urea was prepared from
[0133] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0134] 2-methyl-4-chloro-N-methyl-2-pyrrole carboxamide according to the method of Embodiment 39.
Embodiment 53
Synthesis of Compound 15
[0135] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylaminoformoxyl)-4-(2-methyl-pyrryl) oxy)phenyl)urea was prepared from
[0136] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-hydroxylphenyl)urea and
[0137] 2-methyl-4-chloro-N-methyl-2-pyrrole carboxamide according to the method of Embodiment 39.
[0138] C: preparing the aromatic heterocyclic substituted acardite derivate having the general formula 2 accroding to method 3
[0000]
Embodiment 54
Preparation of 4-(4-(6-Methoxyquinolinyl)Oxy))Aniline
[0139] 8 g of 4-chloro-6-methoxyquinoline was dissolved in DMF, added with 20 g of potassium tert-butylate and 10 g of 4-aminophenol and reacted under the protection of nitrogen at 70° C. for 8 hours. After the end of the reaction, the reaction liquid was poured into 250 ml of ethyl acetate and 250 ml of saturated salt water and mixed evenly followed by liquid separation. The water solution was extracted with ethyl acetate.
[0140] The ethyl acetate layer was added with saturated salt water for washing and dried by anhydrous sodium sulfate. The solvent was evaporated under vacuum to obtain 6 g of 4-(4-(6-methoxyquinolinyl)oxy))aniline.
Embodiment 55
Preparation of 4-(4-(7Fluoroquinazolinyl)Oxy)Aniline
[0141] Prepared from 4-chloroquinazoline with reference to the method of embodiment 54.
Embodiment 56
Preparation of 4-(5-(4-Methoxypyrimidinyl)Oxy)Aniline
[0142] Prepared from 5-chloro-4-methoxypyrimidine with reference to the method of embodiment 54.
Embodiment 57
Preparation of 4-(4-(7-Amino-Isoquinolyl)Oxy)Aniline
[0143] Prepared from 4-chloro-7-aminoisoquinoline with reference to the method of embodiment 54.
Embodiment 58
Preparation of 4-(4-(2-Methyl-Pyrryl)Oxy)Aniline
[0144] Prepared from 4-chloro-2-methylpyrrol with reference to the method of embodiment 54.
Embodiment: 59
Preparation of 4-(4-(6-Methoxyl-7-Fluoro-Quinolinyl)Oxy)Aniline
[0145] Prepared from 4-chloro-6-methoxyl-7-fluoro-quinoline with reference to the method of embodiment 54.
Embodiment: 60
Preparation of 4-(4-(6-Methyl-7-Fluoro-Quinolinyl)Oxy))Aniline
[0146] Prepared from 4-chloro-6-methyl-7-fluoro-quinazoline with reference to the method of embodiment 54.
Embodiment 61
Synthesis of 4-Chloro-3-(Trifluoromethyl)Phenyl Isocyanate
[0147] 100 ml of diphosgene is mixed with 20 g of 4-chloro-3-(trifluoromethyl)aniline and refluxed for 12 hours. The reaction liquid was added into toluene, and the solvent was evaporated under vacuum to obtain the product 4-chloro-3-(trifluoromethyl)phenyl isocyanate.
Embodiment 62
Synthesis of 4-Bromo-3-(Trifluoromethyl)Phenyl Isocyanate
[0148] Prepared from 4-bromo-3-(trifluoromethyl)aniline with reference to the method of embodiment 61.
Embodiment 63
Synthesis of 4-Fluoro-3-(Trifluoromethyl)Phenyl Isocyanate
[0149] Prepared from 4-fluoro-3-(trifluoromethyl)aniline with reference to the method of embodiment 61.
Embodiment 64
Synthesis of 4-Chloro-3-Ethylphenyl Isocyanate
[0150] Prepared from 4-chloro-3-ethylaniline with reference to the method of embodiment 61.
Embodiment 65
Synthesis of 4-Ethyl-3-Trifluoromethyl
[0151] Prepared from 4-ethyl3-trifluoromethylaniline with reference to the method of embodiment 61.
Embodiment 66
Synthesis of
[0152] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-quinolinyl)oxyphenyl)urea (compound 16) 7 g of 4-(4-(6-methoxyquinolinyl)oxy))aniline4-(4-quinolinyl)oxyaniline (prepared from embodiment 54), 5 g of 4-chloro-3-(trifluoromethyl)phenyl isocyanate (prepared from embodiment 61) and 50 ml of methylene dichloride were mixed and reacted at room temperature for 24 hours, and the crystal was precipitated, followed by air pump filtration and collection to obtain
[0153] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea.
Embodiment 67
Synthesis of Compound 17
[0154] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea was prepared from 4-(4-(6-methoxyquinolinyl)oxy))aniline and 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the method of Embodiment 66.
Embodiment 68
Synthesis of Compound 18
[0155] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea was prepared from 4-(4-(6-methoxyquinolinyl)oxy))aniline and 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 69
Synthesis of Compound 19
[0156] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(7fluoroquinazolinyl)oxy)phenyl)urea was prepared from 4-(4-(7fluoroquinazolinyl)oxy)aniline (prepared from embodiment 55) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 70
Synthesis of Compound 20
[0157] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(7fluoroquinazolinyl)oxy)phenyl)urea was prepared from 4-(4-(7fluoroquinazolinyl)oxy)aniline and 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 71
Synthesis of Compound 21
[0158] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(4-(7fluoroquinazolinyl)oxy)phenyl)urea was prepared from 4-(4-(7fluoroquinazolinyl)oxy)aniline and 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 72
Synthesis of Compound 22
[0159] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(5-(4-methoxypyrimidinyl)oxy)phenyl)urea was prepared from 4-(5-(4-methoxypyrimidinyl)oxy)aniline (prepared from embodiment 56) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 73
Synthesis of Compound 23
[0160] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(5-(4-methoxypyrimidinyl)oxy)phenyl)urea was prepared from 4-(5-(4-methoxypyrimidinyl)oxy)aniline and 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 74
Synthesis of Compound 24
[0161] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(5-(4-methoxypyrimidinyl)oxy)phenyl)urea was prepared from 4-(5-(4-methoxypyrimidinyl)oxy)aniline and 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 75
Synthesis of Compound 25
[0162] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(7-amino-isoquinolyl)oxy)phenyl)urea was prepared from 4-(4-(7-amino-isoquinolyl)oxy)aniline (prepared from embodiment 57) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 76
Synthesis of Compound 26
[0163] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(7-amino-isoquinolyl)oxy)phenyl)urea was prepared from 4-(4-(7-amino-isoquinolyl)oxy)aniline and 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 77
Synthesis of Compound 27
[0164] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(4-(7-amino-isoquinolyl)oxy)phenyl)urea was prepared from 4-(4-(7-amino-isoquinolyl)oxy)aniline and 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 78
Synthesis of Compound 28
[0165] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(2-methyl-pyrryl)oxy)phenyl)urea was prepared from 4-(4-(2-methyl-pyrryl)oxy)aniline (prepared from embodiment 58) and 4-chloro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 79
Synthesis of Compound 29
[0166] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(2-methyl-pyrryl)oxy)phenyl)urea was prepared from 4-(4-(5-methyl-pyrryl)oxy)aniline and 4-fluoro-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 80
Synthesis of Compound 30
[0167] N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-(4-(4-(2-methyl-pyrryl)oxy)phenyl)urea was prepared from 4-(4-(5-methyl-pyrryl)oxy)aniline and 4-bromo-3-(trifluoromethyl)phenyl isocyanate according to the methd of Embodiment 66.
Embodiment 81
Synthesis of Compound 31
[0168] N-(4-chloro-3-ethylphenyl)-N′-(4-(4-(6-methoxyl-7-fluoro-quinolinyl)oxy)phenyl)urea was prepared from 4-(4-(6-methoxyl-7-fluoro-quinolinyl)oxy)aniline (prepared from embodiment 59) and 4-chloro-3-ethylphenyl isocyanate (prepared from embodiment 64) according to the methd of Embodiment 66.
Embodiment 82
Synthesis of Compound 32
[0169] N-(4-ethyl-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-methoxyl-7-fluoro-quinolinyl)oxy)phenyl)urea was prepared from 4-(4-(6-methoxyl-7-fluoro-quinolinyl)oxy)aniline (prepared from embodiment 59) and 4-ethyl-3-trifluoromethyl isocyanate (prepared from embodiment 65) according to the methd of Embodiment 66.
Embodiment 83
Synthesis of Compound 33
[0170] N-(4-chloro-3-ethylphenyl)-N′-(4-(4-(6-methyl-7-fluoro-quinolinyl)oxy))phenyl)urea was prepared from 4-(4-(6-methyl-7-fluoro-quinolinyl)oxy))aniline (prepared from embodiment 60) and 4-chloro-3-ethylphenyl isocyanate (prepared from embodiment 64) according to the methd of Embodiment 66.
Embodiment 84
Synthesis of Compound 34
[0171] N-(4-ethyl-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-methyl-7-fluoro-quinolinyl)oxy))phenyl)urea was prepared from 4-(4-(6-methyl-7-fluoro-quinolinyl)oxy))aniline (prepared from embodiment 60) and 4-ethyl-3-trifluoromethyl isocyanate (prepared from embodiment 65) according to the methd of Embodiment 66.
Embodiment 85
Preparation of 4-Chloro-7-Nitrylquinoline-2-Carbonyl Chloride
[0172] Prepared from 4-hydroxyl-7-nitryl-2-quinoline carboxylic acid with reference to the method of embodiment 1.
Embodiment 86
Preparation of 4-Chloro-7-Trifluoromethylquinazoline-2-Carbonyl Chloride
[0173] Prepared from 4-hydroxyl-7-trifluoromethyl-2-quinazoline carboxylic acid with reference to the method of embodiment 1.
Embodiment 87
Preparation of 4-Chloro-7-Nitryl-N-Ethyl-2-Quinoline Carboxamide
[0174] Prepared from 4-chloro-7-nitrylquinoline-2-carbonyl chloride (prepared from embodiment 58) and 2M ethylamine ethanol solution with reference to the method of embodiment 6.
Embodiment 88
Preparation of 4-Chloro-7-Trifluoromethyl-N-Propyl-2-Quinazoline Methanamide
[0175] Prepared from 4-chloro-7-trifluoromethylquinazoline-2-carbonyl chloride (prepared from embodiment 86) and 2M propylamine ethanol solution with reference to the method of embodiment 6.
Embodiment 89
Preparation of
[0176] 2-methyl-4-(2-(N-ethylcarbamyl)-4-(7-nitrylquinolinyl)oxy))aniline
[0177] Prepared from 4-chloro-7-nitryl-N-ethyl-2-quinoline carboxamide (prepared from embodiment 87) and 3-methyl-4-aminophenol with reference to the method of embodiment 11.
Embodiment 90
Preparation of 2-Methoxyl-4-(2-(N-Ethylcarbamyl)-4-(7-Nitrylquinolinyl)Oxy))Aniline
[0178] Prepared from 4-chloro-7-nitryl-N-ethyl-2-quinoline carboxamide (prepared from embodiment 87) and 3-methoxyl-4-aminophenol with reference to the method of embodiment 11.
Embodiment 91
Preparation of 2-Fluoro-4-(2-(N-Propylcarbamyl)-4-(7-Trifluoromethylquinolinyl)Oxy)) Aniline
[0179] Prepared from 4-chloro-7-trifluoromethyl-N-propyl-2-quinazoline methanamide (prepared from embodiment 88) and 3-fluoro-4-aminophenol with reference to the method of embodiment 11.
Embodiment 92
Preparation of 2-Trifluoromethyl-4-(2-(N-Propylcarbamyl)-4-(7-Trifluoromethylquinolinyl)Oxy))Aniline
[0180] Prepared from 4-chloro-7-trifluoromethyl-N-propyl-2-quinazoline methanamide (prepared from embodiment 88) and 4-amino-3-trifluoromethyl phenol with reference to the method of embodiment 11.
Embodiment 93
Synthesis of 4-Chloro-3-Methoxyphenyl Isocyanate
[0181] Prepared from 4-chloro-3-methoxyaniline with reference to the method of embodiment 61.
Embodiment 94
Preparation of Compound 35
[0182] N-(4-chloro-3-methoxyphenyl)-N′-(2-methyl-4-(2-(N-ethylcarbamyl)-4-(7-nitryl-quinolinyl)ox y)phenyl)urea was sythesized from 2-methyl-4-(2-(N-ethylcarbamyl)-4-(7-nitrylquinolinyl)oxy))aniline (prepared from embodiment 89) and 4-chloro-3-methoxyphenyl isocyanate (prepared from embodiment 93) according to the method of Embodiment 19.
Embodiment 95
Preparation of Compound 36
[0183] N-(4-chloro-3-methoxyphenyl)-N′-(2-methoxyl-4-(2-(N-ethylcarbamyl)-4-(7-nitryl-quinolinyl) oxy)phenyl)urea was sythesized from 2-methoxyl-4-(2-(N-ethylcarbamyl)-4-(7-nitrylquinolinyl)oxy))aniline (prepared from embodiment 90) and 4-chloro-3-methoxyphenyl isocyanate (prepared from embodiment 93) according to the method of Embodiment 19.
Embodiment 96
Preparation of Compound 37
[0184] N-(4-chloro-3-methoxyphenyl)-N′-(2-fluoro-4-(2-(N-propylcarbamyl)-4-(7-trifluoromethylqui nolinyl)oxy))phenyl)urea was sythesized from 2-fluoro-4-(2-(N-propylcarbamyl)-4-(7-trifluoromethylquinolinyl)oxy))aniline (prepared from embodiment 91) and 4-chloro-3-methoxyphenyl isocyanate (prepared from embodiment 93) according to the method of Embodiment 19.
Embodiment 97
Preparation of Compound 38
[0185] N-(4-chloro-3-methoxyphenyl)-N′-(2-trifluoromethyl-4-(2-(N-propylcarbamyl)-4-(7-trifluorom ethylquinolinyl)oxy))phenyl)urea was sythesized from
[0186] 2-trifluoromethyl-4-(2-(N-propylcarbamyl)-4-(7-trifluoromethylquinolinyl)oxy))aniline (prepared from embodiment 92) and 4-chloro-3-methoxyphenyl isocyanate (prepared from embodiment 93) according to the method of Embodiment 19.
Embodiment 98
Synthesis of N-(4-Chloro-3-(Trifluoromethyl)Phenyl)-N′-(4-(4-(6-Methoxyquinolinyl)Oxy))Phenyl)Urea Mesylate
[0187] 10 g of N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea free base was dissolved in 300 ml of ether and added with methanesulfonic acid/ethanol solution in drops at room temperature until pH=2, and white crystal was precipitated followed by air pump filtration and collection to obtain N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea mesylate.
Embodiment 99
[0188] Synthesis of Pharmaceutically Acceptable Salts of N-(4-Chloro-3-(Trifluoromethyl)Phenyl)-N′-(4-(4-(6-Methoxyquinolinyl)Oxy))Phenyl)Urea
[0189] With reference to the method of embodiment 85, fluoromethanesulfonic acid/ethanol solution, benzene sulfonic acid/ethanol solution, p-toluenesulfonic acid/ethanol solution, 1-naphthalenesulfonic acid/ethanol solution, 2-naphthalenesulfonic acid/ethanol solution, acetic acid/ethanol solution, trifluoroacetic acid/ethanol solution, malic acid/ethanol solution, tartaric acid/ethanol solution, citric acid/ethanol solution, lactic acid/ethanol solution, oxalic acid/ethanol solution, succinic acid/ethanol solution, fumaric acid/ethanol solution, maleic acid/ethanol solution, benzoic acid/ethanol solution, salicylic acid/ethanol solution, phenylacetic acid/ethanol solution or mandelic acid/ethanol solution were added in drops to synthesize trifluoromethylsulfonate, benzene sulfonate, tosilate, 1-naphthalenesulfenesulfonate, 2-naphthalenesulfenesulfonate, acetate, trifluoroactate, malate, tartrate, citrate, lactate, oxalate, succinate, fumarate, maleate, benzoate, salicylate, phenylacetate or mandelate of N-(4-chloro-3 -(trifluoromethyl)phenyl)-N′-(4-(4-quinolinyl)oxyphenyl)urea.
[0190] The pharmaceutically acceptable salts of compounds 17-38 can be also synthesized according to the above mentioned method.
[0191] The compounds in table 1 to 14 were prepared according to methods of the above mentioned embodiments, and the characteristics are shown in the following tables.
[0000]
TABLE 1
substituted quinoline derivatives
Compound
Elementary
Mass spectrum
No.
R 3
analysis
Name
M + 1
1
4-chloro-3-
C: 57.3
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
545.5
trifluoromethyl
H: 3.8
(4-(2-(N-methylaminoformoxyl)-4-(6-
N: 10.3
methoxyquinolinyl)oxy))phenyl)urea
2
4-fluoro-3-
C: 59.2
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
529
trifluoromethyl
H: 3.9
(4-(2-(N-methylaminoformoxyl)-4-(6-
N: 10.5
methoxyquinolinyl)oxy))phenyl)urea
3
4-bromo-3-
C: 53.0
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
590
trifluoromethyl
H: 3.31
(4-(2-(N-methylaminoformoxyl)-4-(6-
N: 9.38
methoxyquinolinyl)oxy))phenyl)urea
[0000]
TABLE 2
substituted quinazoline derivatives
Compound
Elementary
Mass spectrum
No.
R 3
analysis
Name
M + 1
4
4-chloro-3-
C: 54.1
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
534.5
trifluoromethyl
H: 3.11
(4-(2-(N-methylaminoformoxyl)-4-
N: 13.0
(7 fluoroquinazolinyl)oxy)phenyl)urea
5
4-fluoro-3-
C: 55.5
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
518
trifluoromethyl
H: 3.30
(4-(2-(N-methylaminoformoxyl)-4-
N: 13.4
(7 fluoroquinazolinyl)oxy)phenyl)urea
6
4-bromo-3-
C: 49.7
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
579
trifluoromethyl
H: 2.91
(4-(2-(N-methylaminoformoxyl)-4-
N: 12.2
(7 fluoroquinazolinyl)oxy)phenyl)urea
[0000]
TABLE 3
substituted pyrimidine derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
7
4-chloro-3-
C: 50.9
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
496.5
trifluoromethyl
H: 3.48
(4-(2-(N-methylaminoformoxyl)-5-(4-
N: 14.0
methoxypyrimidinyl)oxy)phenyl)urea
8
4-fluoro-3-
C: 52.5
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
480
trifluoromethyl
H: 3.67
(4-(2-(N-methylaminoformoxyl)-5-(4-
N: 14.5
methoxypyrimidinyl)oxy)phenyl)urea
9
4-bromo-3-
C: 46.8
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
541
trifluoromethyl
H: 3.00
(4-(2-(N-methylaminoformoxyl)-5-(4-
N: 13.1
methoxypyrimidinyl)oxy)phenyl)urea
[0000]
TABLE 4
substituted isoquinoline derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
10
4-chloro-3-
C: 56.5
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
530.5
trifluoromethyl
H: 3.70
(4-(2-(N-methylaminoformoxyl)-
N: 13.2
4-(7-amino-isoquinolyl)oxy)phenyl)urea
11
4-fluoro-3-
C: 58.5
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
514
trifluoromethyl
H: 3.81
(4-(2-(N-methylaminoformoxyl)-
N: 13.8
4-(7-amino-isoquinolyl)oxy)phenyl)urea
12
4-bromo-3-
C: 52.4
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
574
trifluoromethyl
H: 3.44
(4-(2-(N-methylaminoformoxyl)-
N: 12.4
4-(7-amino-isoquinolyl)oxy)phenyl)urea
[0000]
TABLE 5
substituted pyrrole derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
13
4-chloro-3-
C: 54.1
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
467.5
trifluoromethyl
H: 4.01
(4-(2-(N-methylaminoformoxyl)-4-(5-
N: 12.2
methyl-pyrryl)oxy)phenyl)urea
14
4-fluoro-3-
C: 55.8
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
451
trifluoromethyl
H: 4.02
(4-(2-(N-methylaminoformoxyl)-4-(5-
N: 12.6
methyl-pyrryl)oxy)phenyl)urea
15
4-bromo-3-
C: 49.5
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
511
trifluoromethyl
H: 3.70
(4-(2-(N-methylaminoformoxyl)-4-(5-
N: 11.0
methyl-pyrryl)oxy)phenyl)urea
[0000]
TABLE 6
substituted quinoline derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
16
4-chloro-3-
C: 59.2
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
488.5
trifluoromethyl
H: 3.70
(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea
N: 8.77
17
4-fluoro-3-
C: 61.3
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
472
trifluoromethyl
H: 3.81
(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea
N: 8.80
18
4-bromo-3-
C: 54.0
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
532
trifluoromethyl
H: 3.40
(4-(4-(6-methoxyquinolinyl)oxy))phenyl)urea
N: 7.79
[0000]
TABLE 7
substituted quinazoline derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
19
4-chloro-3-
C: 55.5
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
477.5
trifluoromethyl
H: 2.91
(4-(4-(7 fluoroquinazolinyl)oxy)phenyl)urea
N: 11.6
20
4-fluoro-3-
C: 57.7
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
461
trifluoromethyl
H: 2.75
(4-(4-(7 fluoroquinazolinyl)oxy)phenyl)urea
N: 12.2
21
4-bromo-3-
C: 50.5
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
522
trifluoromethyl
H: 2.71
(4-(4-(7 fluoroquinazolinyl)oxy)phenyl)urea
N: 10.8
[0000]
TABLE 8
substituted pyrimidine derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
22
4-chloro-3-
C: 52.1
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
439.5
trifluoromethyl
H: 3.30
(4-(5-(4-methoxypyrimidinyl)oxy)phenyl)
N: 12.8
23
4-fluoro-3-
C: 54.2
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
423
trifluoromethyl
H: 3.38
(4-(5-(4-methoxypyrimidinyl)oxy)phenyl)
N: 13.3
24
4-bromo-3-
C: 47.2
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
484
trifluoromethyl
H: 2.99
(4-(5-(4-methoxypyrimidinyl)oxy)phenyl)
N: 11.4
[0000]
TABLE 9
substituted isoquinoline derivatives
Compound
Elementary
Mass
No.
R 3
analysis %
Name
spectrum m/e
25
4-chloro-3-
C: 58.4
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
473.5
trifluoromethyl
H: 3.38
(4-(4-(7-amino-isoquinolyl)oxy)phenyl)urea
N: 11.81
26
4-fluoro-3-
C: 60.7
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
457
trifluoromethyl
H: 3.70
(4-(4-(7-amino-isoquinolyl)oxy)phenyl)urea
N: 13.5
27
4-bromo-3-
C: 53.5
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
518
trifluoromethyl
H: 3.40
(4-(4-(7-amino-isoquinolyl)oxy)phenyl)urea
N: 10.7
[0000]
TABLE 10
substituted pyrrole derivatives
Compound
Elementary
Mass
No.
R 3
analysis %
Name
spectrum m/e
28
4-chloro-3-
C: 55.7
N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-
410.5
trifluoromethyl
H: 3.75
(4-(4-(2-methyl-pyrryl)oxy)phenyl)urea
N: 10.4
29
4-fluoro-3-
C: 58.2
N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-
395
trifluoromethyl
H: 4.01
(4-(4-(2-methyl-pyrryl)oxy)phenyl)urea
N %: 10.5
30
4-bromo-3-
C: 50.3
N-(4-bromo-3-(trifluoromethyl)phenyl)-N′-
455
trifluoromethyl
H: 3.49
(4-(4-(2-methyl-pyrryl)oxy)phenyl)urea
N: 9.41
[0000]
TABLE 11
polysubstituted quinoline derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
31
4-chloro-3-
C: 64.6
N-(4-chloro-3-ethylphenyl)-N′-(4-(4-(6-
466.5
ethyl
H: 4.71
methoxyl-7-fluoro-quinolinyl)oxy)phenyl)urea
N: 9.20
32
4-ethyl-3-
C: 62.7
N-(4-ethyl-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-
501.5
trifluoromethyl
H: 4.36
methoxyl-7-fluoro-quinolinyl)oxy)phenyl)urea
N: 8.22
[0000]
TABLE 12
polysubstituted quinazoline derivatives
Compound
Elementary
Mass
No.
R 3
analysis
Name
spectrum m/e
33
4-chloro-3-
C: 64.1
N-(4-chloro-3-ethylphenyl)-N′-(4-(4-(6-
451.5
ethyl
H: 4.70
methyl-7-fluoro-quinolinyl)oxy)phenyl)urea
N: 12.3
34
4-ethyl-3-
C: 61.8
N-(4-ethyl-3-(trifluoromethyl)phenyl)-N′-(4-(4-(6-
485
trifluoromethyl
H: 4.01
methyl-7-fluoro-quinolinyl)oxy)phenyl)urea
N: 11.38
[0000]
TABLE 13
substituted quinoline derivatives
Compound
Elementary
Mass
No.
R 2
analysis
Name
spectrum m/e
35
2-methyl
C: 59.1
N-(4-chloro-3-methoxyphenyl)-N′-
550.5
H: 4.32
(2-methyl-4-(2-(N-ethylcarbamyl)-4-
N: 12.5
(7-nitryl-quinolinyl)oxy)phenyl)urea
36
2-methoxy
C: 57.2
N-(4-chloro-3-methoxyphenyl)-N′-
566.5
H: 4.36
(2-methoxyl-4-(2-(N-ethylcarbamyl)-4-
N: 12.2
(7-nitryl-quinolinyl)oxy)phenyl)urea
[0000]
TABLE 14
substituted quinazoline derivatives
Compound
Elementary
Mass
No.
R 2
analysis
Name
spectrum m/e
37
2-fluoro
C: 56.1
N-(4-chloro-3-methoxyphenyl)-N′-
579.5
H: 4.17
(2-fluoro-4-(2-(N-propylcarbamyl)-4-
N: 9.72
(7-trifluoromethylquinolinyl)oxy))phenyl)urea
38
2-trifluoro-
C: 53.4
N-(4-chloro-3-methoxyphenyl)-N′-
629.5
methyl
H: 3.91
(2-trifluoromethyl-4-(2-(N-propylcarbamyl)-4-
N: 8.58
(7-trifluoromethylquinolinyl)oxy))phenyl)urea
Determination of Antitumor Activity
[0192] 1. Inhibitory activity of the compound of the present invention on raf kinase
[Test Method]
[0193] Raf-1 inhibitor screening by chemoluminescence method
[0194] [Instruments]
[0195] Westernblot electrophoresis apparatus Rotaryshaker
[Test Materials]
[0196] Raf-1(truncated), Magnesium/ATP Cocktail, MEK1 unactive
[Tested Samples]
[0197] Compounds 1-38
[Positive Control]
[0198] Sorafenib
[0000]
Inhibiton
rate
%
=
Gray
value
of
the
negative
control
group
-
gray
value
of
the
drug
-
treated
group
Gray
value
of
the
negative
control
group
×
100
%
[Results]
[0199]
[0000]
TABLE 13
Inhibition of compounds 1-16 and positive control medicine on raf kinase
Compound
Final concentration
Inhibition
Compound
Final concentration
Inhibition
No.
1.0*10 −5 mol/ml
rate %
Activity
No.
1.0*10 −5 mol/ml
rate %
Activity
1
1
75.0
+
9
1
99.2
+
2
1
61.1
+
10
1
3.5
3
1
56.3
+
11
1
11.2
4
1
82.2
+
12
1
12.1
5
1
98.9
+
13
1
55.0
+
6
1
80.1
+
14
1
41.3
7
1
99.1
+
15
1
35.5
8
1
44..5
16
1
62.1
+
Positive
1
85.7
+
control
medicine
[0000]
TABLE 14
Inhibition of compounds 17-38 and positive control medicine on raf kinase
Compound
Final concentration
Inhibition
Compound
Final concentration
Inhibition
No.
1.0*10 −5 mol/ml
rate %
Activity
No.
1.0*10 −5 mol/ml
rate %
Activity
17
1
58.2
+
28
1
33.5
18
1
34.4
29
1
85.3
+
19
1
93.5
+
30
1
16.8
20
1
87.7
+
31
1
89.4
+
21
1
98.9
+
32
1
90.5
+
22
1
88.1
+
33
1
92.3
+
23
1
89.9
+
34
1
96.2
+
24
1
91.3
+
35
1
45.3
25
1
11.5
36
1
81.2
+
26
1
15.3
37
1
81.5
+
27
1
8.8
38
1
88.1
+
Positive
1
85.7
+
control
medicine
[0200] The test results of inhibitory activity of the compound on raf kinase showed that the inhibitory activity of the compound in the present invention is better than or equivalent to positive control medicine sorafenib. The test results indicate that these compounds can affect the survival, proliferation and disease progression of tumor cells through inhibiting the raf kinase and blocking the ras protein signal transduction cascade of tumor cells. The compound of the present invention has potential of being applied to treat tumor and leukemia.
[0201] 2. Experimental therapeutic action of the compound in the present invention on S180 sarcoma mice
[Test Materials]
[0202] Test animals: ICR mice, 18-25 g
[0203] Tumor types: mice S180 sarcoma, provided by Shanghai Institute of Materia Medica, Chinese Academy of Sciences.
Positive control medicine: Sorafenib Tested samples: compounds 1-38
[Test Method]
[0206] 18-25 g female ICR mice and well grown 7-11 day old mice sarcoma S180 tumor seeds were selected, and the seeds were inoculated into the subcutaneous at the right axillary. After inoculated 24 hours, these mice were randomly divided into cages and orally administrated 60 mg/kg for 9 days. On 10 day, the animals were killed and weighed, and the tumor weights were weighed to calculate average tumor weight in each group, followed by calculating the tumor inhibition rate according to the following formula and T test.
[0000]
Tumor
growth
inhibition
rate
=
Average
tumor
weight
in
the
control
group
-
average
tumor
weight
in
the
treatment
group
average
tumor
weight
in
the
treatment
group
×
100
%
[0207] [Determination Results]
[0000]
TABLE 15
Tumor growth inhibition rate of compounds 1-3 and sorafenib on mice S180 sarcoma
Administration
Animal number
Weight (g)
Tumor weight
Inhibition
Groups
Dosage
methods
Start
Final
Start
Final
x ± SD(g)
rate (%)
P value
Normal
0.4
ml/mouse
ig
20
20
18.9 ± 1.5
22.0 ± 3.4
1.61 ± 0.36
saline
Sora
60
mg/kg
ig
10
10
18.8 ± 1.2
21.7 ± 2.4
0.71 ± 0.30
55.9
<0.05
Compound 1
60
mg/kg
ig
10
10
18.7 ± 1.9
22.3 ± 1.3
0.99 ± 0.20
38.5
<0.05
Compound 2
60
mg/kg
ig
10
10
18.9 ± 1.7
20.9 ± 2.3
0.87 ± 0.24
46.0
<0.05
Compound 3
60
mg/kg
ig
10
10
18.0 ± 1.1
20.2 ± 2.5
0.75 ± 0.36
53.4
<0.05
[0000]
TABLE 16
Tumor growth inhibition rate of compounds 1-12 and sorafenib on mice S180 sarcoma (%)
1
2
3
4
5
6
7
8
9
10
11
12
Sorafenib
Mice
38.5
24.1
53.4
50.1
49.3
51.2
21.5
58.2
55.9
55.2
54.2
45.7
55.9%
S180
sarcoma
[0000]
TABLE 17
Tumor growth inhibition rate of compounds 13-26 and sorafenib on mice S180 sarcoma (%)
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Mice
21.2
18.2
56.7
33.6
44.2
35.7
50.8
54.6
59.7
52.1
51.5
54.6
55.8
7.6
S180
sarcoma
[0000]
TABLE 18
Tumor growth inhibition rate of compounds 27-38
and sorafenib on mice S180 sarcoma (%)
27
28
29
30
31
32
33
34
35
36
37
38
Mice
55.1
11.5
14.2
55.2
50.3
49.8
55.3
52.6
55.8
55.1
24.1
59.2
S180
sarcoma
[0208] 3. Experimental therapeutic action of the compound in the present invention on Human colon cancer HT-29 transplantable tumor in nude mice.
[0209] [Test Materials]
Test animals: Female BALB/cA nude mice, 35-40 day old, with weight of 18-22 g. Tumor seeds: Human colon cancer HT-29 transplantable tumor in nude mice, established by inoculating human colon cancer HT-29 cell strains subcutaneously in nude mice Positive control medicine: Sorafenib Tested samples: Compounds 1-38
[Test Method]
[0214] Take eugenic tumor tissues and cut into about 1.5 mm 3 , and then incoculate subcutaneously at the right armpit of nude mice under the sterile conditions. The diameter of the transplantable tumor in nude mice was determined with a vernier caliper, and the animals were divided into groups after the tumors were grown to 100-300 mm 3 . Using the method of measuring the tumor diameter, dynamically observe the antitumor effects of tested materials. The diameter of the tumor was determined three times every week and the mouse weight was weighed at the same time. The mice were intragastrically administrated with Sorafenib and tested drugs, 60 mg/kg, for continuous 9 times. The solvent was intragastrically administrated as the control for continuous 9 times. Equal amount of control was administrated in the negative control group. Tumor volume (TV) is calculated as: TV=1/2×a×b 2 , wherein a and b respectively represent length and width.
[0215] Relative tumor volume (RTV) is calculated as: RTV=TV t /TV 0 , wherein TV 0 is the tumor volume when administrated according to different cages and TV t is the tumor volume measured each time.
[0216] Relative tumor reproduction rate T/C (%) is calculated as follows:
[0000]
T
/
C
(
%
)
=
T
RTV
C
RTV
×
100
[0217] T RTV : RTV in the treatment group; C RTV : RTV in the negative control group.
[0218] The test results used relative tumor reproduction rate T/C (%) as evaluating indicator of anti-tumor activity.
[0219] Evaluation of in vivo anti-tumor activity
[0000]
T/C %
Evaluation
≧60
(−) No activity
60-50
(+/−) Marginal activity
50-40
(+) Moderate-strength activity
40-10
(++) High-strength activity
≦10
(+++)Extremenly high-strength activity
[0220] [Determination results]
[0000]
TABLE 19
Experimental treatment of compounds 1-3 and Sorafenib on human
colon cancer HT-29 transplantable tumor in nude mice
Animal
Dosage
number
Weight (g)
TV
T/C
Groups
mg/kg
Start
Final
d0
d13
d0
d13
RTV
(%)
Control
6
6
18.8 ± 1.1
19.6 ± 0.9
133 ± 60
626 ± 226
5.07 ± 1.39
Solvent control
6
6
19.7 ± 0.6
20.8 ± 0.8
133 ± 32
547 ± 172
4.15 ± 0.93
81.85
Sorafenib
60
6
6
19.9 ± 1.1
20.4 ± 1.4
133 ± 33
308 ± 86
2.36 ± 0.57
46.48**
Compound 1
60
6
6
19.5 ± 1.0
20.5 ± 1.1
128 ± 34
359 ± 108
2.81 ± 1.05
55.42**
Compound 2
60
6
6
19.9 ± 0.8
21.0 ± 0.8
133 ± 23
265 ± 100
2.00 ± 0.41
39.45**
Compound 3
60
6
6
19.1 ± 1.0
19.7 ± 1.4
133 ± 18
322 ± 129
2.40 ± 0.67
47.34**
[0000]
TABLE 20
Relative tumor reproduction rate of compounds 1-10 and Sorafenib on
Human colon cancer HT-29 transplantable tumor in nude mice T/C (%)
1
2
3
4
5
6
7
8
9
10
Sorafenib
Human colon cancer
55.42
39.45
47.34
33.15
38.24
39.58
40.1
37.6
35.2
78.9
46.48
HT-29 transplantable
tumor in nude mice
[0000]
TABLE 21
Relative tumor reproduction rate of compounds 11-20 and Sorafenib on
human colon cancer HT-29 transplantable tumor in nude mice T/C (%)
11
12
13
14
15
16
17
18
19
20
Human colon
81.2
80.5
81.2
40.1
85.2
55.2
54.7
40.2
39.4
40.1
cancer HT-29
transplantable
tumor in nude
mice
[0000]
TABLE 22
Relative tumor reproduction rate of compounds 21-30 and Sorafenib on
human colon cancer HT-29 transplantable tumor in nude mice T/C (%)
21
22
23
24
25
26
27
28
29
30
Human colon
38.7
41.2
39.7
37.8
79.5
41.1
80.3
39.1
78.3
79.5
cancer HT-29
transplatable
tumor in nude
mice
[0000]
TABLE 23
Relative tumor reproduction rate of compounds
31-38 and Sorafenib on human colon cancer HT-29
transplantable tumor in nude mice T/C (%)
31
32
33
34
35
36
37
38
Human colon
50.3
46.2
39.9
45.9
51.2
41.5
39.5
41.2
cancer HT-29
transplantable
tumor in
nude mice
[0221] The results of the above in vivo and vitro tumor inhibition tests showed that the inhibiting effects of such derivatives on S180 sarcoma in mice and human colon cancer HT-29 transplantable tumor in nude mice were better than or equivalent to positive control medicine sorafenib.The test results showed that the compound of the present invention or the pharmaceutically acceptable salt thereof can be used for treating tumor or leukemia. The pharmacodynamic experiments of the compounds in the present invention, positive control medicine sorafenib and compounds A′, B′ and C′ with no substituent or only amino formyl in A ring on human lung cancer cell strain A549, human high-metastic lung cancer cell strain 95D, lung cancer cell A549, human umbilical vein endothelial cell HUVEC cell growth and lumen formation, human lung cancer A549 cell transplantation tumor model in nude mice, human liver cancer cell bel-7402 transplantation tumor model in nude mice, and renal carcinoma cell line GCR-1 transplantation tumor model in nude mice were carried out to verify the effect of the compounds of the present invention.
[0222] Sorafenib was abbreviated as Sorafenib hereafter, and the compounds A′, B′ and C′ were respectively prepared according the method of CN200810129360.6, which were compounds with no substituent in A ring, wherein A′ is
[0223] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-quinolinyl)oxy)phenyl)urea, B′is
[0224] N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(4-pyrimidinyl)oxy)phenyl)urea, and C′
[0225] N-(4-fluoro-3-(trifluoromethyl)phenyl)-N′-(4-(4-pyrryl)oxy)phenyl)urea.
[0226] 4. Using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT) to detect the inhibition effects on the growth of human lung cancer cell strain A549
[0227] [Test materials] MTT working solution, F12 medium containing 10% FBS, continuous injectors
[0228] [Tested compound] Compounds 1-38
[0229] [Positive control medicine] Sorafenib, compounds A′, B′, C′ with no substituent or only amino formyl in A ring
[0230] The inhibition rate is calculated as follows:
[0000]
Cell
reproduction
rate
%
=
1
-
(
Relative
OD
value
of
conrol
well
-
Relative
OD
value
of
drug
well
)
Relative
OD
value
of
conrol
well
×
100
%
[0231] Relative OD value of conrol well=OD value of control well−OD value of blank well
[0232] Relative OD value of drug well=OD value of drug well−OD value of blank well
[Screening Results]
[0233]
[0000]
TABLE 24
Inhibition effects of compounds 1-18 on
the growth of human lung cancer cell A549
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
1
1
50.20%
+
2
1
61.11%
++
3
1
69.67%
++
4
1
91.12%
+++
5
1
93.50%
+++
6
1
92.50%
+++
7
1
45.30%
+
8
1
60.67%
++
9
1
61.54%
++
10
1
74.50%
++
11
1
69.20%
++
12
1
42.31%
+
13
1
64.23%
++
14
1
67.25%
++
15
1
72.17%
++
16
1
89.71%
+++
17
1
88.52%
+++
18
1
90.71%
+++
[0000]
TABLE 25
Inhibition effects of compounds 19-38 on
the growth of human lung cancer cell A549
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/ml
rate
Activity
19
1
91.23%
+++
20
1
88.32%
+++
21
1
89.21%
+++
22
1
82.49%
+++
23
1
55.41%
+
24
1
86.32%
+++
25
1
63.26%
+
26
1
55.50%
+
27
1
64.71%
+
28
1
88.52%
+++
29
1
86.42%
+++
30
1
85.47%
+++
31
1
46.78%
+
32
1
45.76%
+
33
1
57.53%
+
34
1
59.52%
+
35
1
55.74%
+
36
1
72.45%
++
37
1
71.65%
++
38
1
74.56%
++
Posive Sorafenib
1
54.60%
+
Compound A′
1
58.51%
+
Compound B′
1
61.62%
+
Compound C′
1
62.25%
+
[0234] 5 Inhibition effects of compounds on human high-metastic lung cancer cell 95D migration
[0235] [Test materials] Boyden Chamber Transwell chamber (with pore size of 8 μm), human high-metastic lung cancer cell 95D cell strain, 1640 medium containing 10% FBS, 1640 medium containing no serum
[0236] [Tested compound] Compounds 1-38
[0237] [Positive control medicine] Sorafenib, compounds A′, B′, C′ with no substituent or only amino formyl in A ring
[0238] The inhibition rate is calculated as follows:
[0000]
Cell
migration
inhibition
rate
%
=
(
migrated
cell
number
in
the
chamber
containing
no
drug
-
migrated
cell
number
in
the
chamber
containing
drug
)
migrated
cell
number
in
the
chamber
containing
no
drug
×
100
%
[Screening Results]
[0239]
[0000]
TABLE 26
Inhibition effects of compounds 1-18 on human high-
metastic lung cancer 95D cell strain migration
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
1
1
80.21%
++
2
1
85.17%
+++
3
1
96.64%
+++
4
1
96.38%
+++
5
1
97.51%
+++
6
1
93.71%
+++
7
1
89.34%
+++
8
1
89.56%
+++
9
1
91.42%
+++
10
1
61.43%
+
11
1
78.66%
++
12
1
66.79%
++
13
1
65.45%
++
14
1
57.57%
+
15
1
63.68%
+
16
1
89.31%
+++
17
1
90.52%
+++
18
1
93.73%
+++
[0000]
TABLE 27
Inhibition effects of compounds 19-38 on human high-
metastic lung cancer 95D cell strain migration
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
19
1
90.21%
+++
20
1
89.12%
+++
21
1
88.76%
+++
22
1
88.77%
+++
23
1
85.53%
+++
24
1
85.48%
+++
25
1
59.76%
+
26
1
60.52%
+
27
1
59.77%
+
28
1
70.53%
+
29
1
61.44%
+
30
1
69.62%
++
31
1
76.18%
++
32
1
66.92%
++
33
1
77.52%
++
34
1
63.65%
+
35
1
68.47%
++
36
1
84.59%
+++
37
1
79.25%
+
38
1
80.53%
+
Positive Sorafenib
1
62.32%
+
Compound A′
1
63.51%
+
Compound B′
1
61.60%
+
Compound C′
1
63.20%
++
[0240] 6. Effects of tested compounds on the adhesive ability of lung cancer cell A549
[0241] [Test materials] gelatin, CCK8, poly-lysine (PLL), A549 cell stains, 1640 medium containing 10% FBS
[0242] [Tested compound] Compounds 1-38 to be tested
[0243] [Positive control medicine] Sorafenib, compounds A′, B′, C′ with no substituent or only amino formyl in A ring
[Screening Results]
[0244] The inhibition rate is calculated as follows:
[0000]
Inhibition
rate
of
cell
adhesion
%
=
Cell
group
without
treatment
(
glutin
adhesion
OD
/
PLL
adhesion
OD
value
)
-
dosing
cell
group
(
glutin
adhesion
OD
/
PLL
adhesion
OD
value
)
Cell
group
without
treatment
(
glutin
adhesion
OD
/
PLL
adhesion
OD
value
)
×
100
%
[0245] Dosing dosing cells without cell group (gelatin adhesive OD/PLL adhesion OD)−Dosing cell group (gelatin adhesive OD/PLL adhesion OD value)
[0246] Dosing dosing cells without cell group (gelatin adhesive OD/PLL adhesion OD value)
[0000]
TABLE 28
Inhibition effects of compounds 1-18 on the adhesion
ability of human lung cancer cell A549
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
1
1
60.22%
+
2
1
75.15%
++
3
1
79.66%
++
4
1
89.71%
+++
5
1
87.58%
+++
6
1
93.59%
+++
7
1
68.34%
++
8
1
61.56%
+
9
1
85.32%
+++
10
1
64.57%
+
11
1
59.63%
+
12
1
62.30%
+
13
1
63.39%
+
14
1
67.51%
++
15
1
68.63%
++
16
1
90.77%
+++
17
1
97.50%
+++
18
1
93.72%
+++
[0000]
TABLE 29
Inhibition effects of compounds 19-38 on the adhesion
ability of human lung cancer cell A549
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
19
1
90.28%
+++
20
1
95.31%
+++
21
1
90.22%
+++
22
1
72.44%
++
23
1
77.56%
++
24
1
73.30%
++
25
1
63.51%
+
26
1
68.57%
++
27
1
94.77%
+++
28
1
90.53%
+++
29
1
91.40%
+++
30
1
92.44%
+++
31
1
66.77%
++
32
1
64.73%
+
33
1
77.59%
++
34
1
76.54%
++
35
1
75.72%
++
36
1
74.50%
++
37
1
71.74%
++
38
1
75.53%
++
Positive medicine
1
72.66%
++
Sorafenib
Compound A′
1
71.55%
++
Compound B′
1
69.26%
++
Compound C′
1
68.62%
++
[0247] 7. Effects of tested compounds on the growth of human umbilical vein endothelial cell HUVEC cell by CCK8 method
[0248] [Test materials] CCK8, human umbilical vein endothelial cell HUVEC cell, 1640 medium containing 10% FBS
[0249] [Tested compound] Compounds 1-38 to be tested
[0250] [Positive control medicine] Sorafenib, compounds A′, B′, C′ with no substituent or only amino formyl in A ring
[Screening Results]
[0251]
Cell
reproduction
rate
%
=
1
-
(
Relative
OD
value
of
conrol
well
-
Relative
OD
value
of
drug
well
)
Relative
OD
value
of
conrol
well
×
100
%
[0252] Relative OD value of conrol well=OD value of control well−OD value of blank well
[0253] Relative OD value of drug well=OD value of drug well−OD value of blank well
[0000]
TABLE 30
Inhibition effects of compounds 1-18 on the growth
of human umbilical vein endothelial cell HUVEC cell
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
1
1
9.20%
2
1
13.11%
3
1
27.67%
4
1
5.12%
5
1
8.50%
6
1
7.50%
7
1
8.30%
8
1
13.67%
9
1
11.54%
10
1
14.50%
11
1
29.20%
12
1
12.31%
13
1
24.23%
14
1
17.25%
15
1
38.17%
16
1
10.71%
17
1
13.52%
18
1
5.71%
[0000]
TABLE 31
Inhibition effects of compounds 19-38 on the growth
of human umbilical vein endothelial cell HUVEC cell
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
19
1
5.23%
20
1
7.32%
21
1
11.21%
22
1
12.49%
23
1
17.41%
24
1
13.32%
25
1
23.26%
26
1
32.50%
27
1
24.73%
28
1
20.55%
29
1
21.40%
30
1
25.46%
31
1
26.70%
32
1
24.77%
33
1
17.50%
34
1
19.52%
35
1
5.74%
36
1
12.45%
37
1
19.65%
38
1
14.56%
Positive medicine
1
22.61%
Sorafenib
Compound A′
1
23.11%
Compound B′
1
31.64%
Compound C′
1
22.27%
[0254] 8. Inhibition effects of compounds on the lumen formation ability of human umbilical vein endothelial cell HUVEC
[0255] [Experimental principles] The human umbilical vein endothelial cells have ability of spontaneously forming blood lumen on Matrigel, which can be used to simulate the process of angiogenesis in vivo. We used Matrigel method to investigate the effects of the compound on the lumen formation ability of human umbilical vein endothelial cell HUVEC.
[0256] [Test materials] HUVEC (taking generation 3 to 5 cells for experiments after obtained from primary separation and cultured at 37 under the conditions of 5% CO 2 ), Matrigel, cell culture medium M199.
[0257] [Tested compound] Compounds 1-38
[0258] [Positive control medicine] Sorafenib, compounds A′, B′, C′ with no substituent or only amino formyl in A ring
[Screening Results]
[0259] The inhibition rate is calculated as follows:
[0000]
Lumen
formation
inhibition
rate
%
=
(
length
sum
of
lumen
without
dosing
-
length
sum
of
lumen
after
dosing
)
length
sum
of
lumen
without
dosing
×
100
%
[0000]
TABLE 32
Inhibition effects of compounds 1-18 on the lumen formation
ability of human umbilical vein endothelial cell HUVEC
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
1
1
72.22%
++
2
1
75.14%
++
3
1
76.61%
++
4
1
86.77%
+++
5
1
87.50%
+++
6
1
90.55%
+++
7
1
60.34%
+
8
1
78.59%
++
9
1
91.45%
+++
10
1
50.34%
+
11
1
79.63%
++
12
1
52.37%
+
13
1
53.36%
+
14
1
67.53%
++
15
1
68.64%
++
16
1
80.79%
++
17
1
67.50%
++
18
1
63.71%
+
[0000]
TABLE 33
Inhibition effects of compounds 19-38 on the lumen formation
ability of human umbilical vein endothelial cell HUVEC
Compound
Final concentration
Inhibition
No.
1.0*10 (−5) mol/L
rate
Activity
19
1
89.22%
+++
20
1
88.54%
+++
21
1
89.47%
+++
22
1
86.72%
+++
23
1
97.56%
+++
24
1
93.78%
+++
25
1
79.79%
++
26
1
70.53%
++
27
1
89.75%
+++
28
1
89.52%
+++
29
1
86.43%
+++
30
1
90.66%
+++
31
1
66.77%
++
32
1
54.74%
+
33
1
67.51%
++
34
1
66.52%
++
35
1
65.70%
++
36
1
64.50%
+
37
1
71.72%
++
38
1
65.55%
++
Positive medicine
1
55.60%
++
Sorafenib
Compound A′
1
60.51%
++
Compound B′
1
61.62%
++
Compound C′
1
60.50%
++
[0260] 9. Tumor inhibition rate of tested compounds on human lung cancer A549 cell transplantation model in nude mice
[0261] [Test animals] female BALB/cA nude mice, 35-40 days old, with weight of 18-22g. There were 12 mice in the negative conrol group and 6 mice in the treatment group.
[0262] [Test method] Take eugenic tumor tissues and cut into about 1.5 mm 3 , and then incoculate subcutaneously at the right armpit of nude mice under the sterile conditions. The diameter of the transplantable tumor in nude mice was determined with a vernier caliper, and the animals were divided into groups after the tumors were grown to 100-300 mm 3 .Using the method of measuring the tumor diameter, dynamically observe the antitumor effects of tested materials.
[0263] The diameter of the tumor was determined three times every week and the mouse weight was weighed at the same time. The dosage of the compound was 60 mg/kg, 6 times every week for 3 weeks. Sorafenib was oral administrated with dosage of 60 mg/kg, 6 times every week for 3 weeks. Equal amount of normal saline was administrated in the negative control group. Observe for one week after administration.
[Detection Indicators and Calculation Methods]
[0264] (1) Tumor volume (TV) is calculated as:
TV=1/2×a×b 2 wherein a and b respectively represents length and width.
[0267] (2) Relative tumor volume (RTV) is calculated as:
RTV=TV t /TV 0°
[0269] wherein TV 0 is the tumor volume when administrated according to different cages and TV t is the tumor volume measured each time.
[0270] (3) Relative tumor reproduction rate T/C (%) is calculated as follows:
[0000]
T
/
C
(
%
)
=
T
RTV
C
RTV
×
100
[0271] T RTV : RTV in the treatment group; C RTV : RTV in the negative control group. The test results used relative tumor reproduction rate T/C (%) as evaluating indicator of anti-tumor activity.
[0272] [Screening results] There was no mortality for the animals in the group of compounds and Sorafenib in the experiments with less toxicity.
[0000]
TABLE 34
Relative tumor reproduction rate of compounds and Sorafenib on human
lung cancer A549 transplantation tumor in nude mice T/C (%)
Relative tumor reproduction rate of compounds 1-10 and Sorafenib on human lung
cancer A549 transplantation tumor in nude mice T/C (%)
1
2
3
4
5
6
7
8
9
10
human lung
38.7
35.3
37.2
12.3
11.6
15.9
39.3
30.5
38.7
30.1
cancer A549
transplantation
tumor
Relative tumor reproduction rate of compounds 11-20 and Sorafenib on human lung
cancer A549 transplantation tumor in nude mice T/C (%)
11
12
13
14
15
16
17
18
19
20
human lung
43.7
36.3
38.4
32.2
38.7
9.9
7.3
12.5
7.7
12.1
cancer A549
transplantation
tumor
Relative tumor reproduction rate of compounds 21-30 and Sorafenib on human lung
cancer A549 transplantation tumor in nude mice T/C (%)
21
22
23
24
25
26
27
28
29
30
human lung
13.7
15.3
17.1
15.6
39.4
33.1
36.3
13.6
14.7
13.1
cancer A549
transplantation
tumor
Relative tumor reproduction rate of compounds 31-38 and Sorafenib on human lung
cancer A549 transplantation tumor in nude mice T/C (%)
31
32
33
34
35
36
37
38
Sorafenib
human lung
38.7
35.3
37.5
22.3
23.6
37.9
38.3
36.5
41.8
cancer A549
transplantation
tumor
Compound A′
Compound B′
Compound C′
human lung
43.2
40.4
36.6
cancer A549
transplantation
tumor
[0273] 10. Tumor inhibition rate of tested compounds on human liver cancer cell bel-7402 transplantation tumor model in nude mice
[0274] [Test animals] female BALB/cA nude mice, 35-40 days old, with weight of 18-22g. There were 12 mice in the negative conrol group and 6 mice in the treatment group.
[0275] [Test method] Take eugenic tumor tissues and cut into about 1.5 mm 3 , and then incoculate subcutaneously at the right armpit of nude mice under the sterile conditions. The diameter of the transplantable tumor in nude mice was determined with a vernier caliper, and the animals were divided into groups after the tumors were grown to 100-300 mm 3 .Using the method of measuring the tumor diameter, dynamically observe the antitumor effects of tested materials.
[0276] The diameter of the tumor was determined three times every week and the mouse weight was weighed at the same time. The dosage of the compound was 60 mg/kg, 6 times every week for 3 weeks. Sorafenib was oral administrated with dosage of 60 mg/kg, 6 times every week for 3 weeks. Equal amount of normal saline was administrated in the negative control group. Observe for one week after administration.
[Detection Indicators and Calculation Methods]
[0277] (1) Tumor volume (TV) is calculated as:
TV=1/2×a×b 2 wherein a and b respectively represents length and width.
[0280] (2) Relative tumor volume (RTV) is calculated as:
RTV=TV t /TV 0°
[0282] wherein TV 0 is the tumor volume when administrated according to different cages (d 0 ) and TV t is the tumor volume measured each time.
[0283] (3) Relative tumor reproduction rate T/C (%) is calculated as follows:
[0000]
T
/
C
(
%
)
=
T
RTV
C
RTV
×
100
[0284] T RTV : RTV in the treatment group; C RTV : RTV in the negative control group. The test results used relative tumor reproduction rate T/C (%) as evaluating indicator of anti-tumor activity.
[0285] [Screening results] There was no mortality for the animals in the group of compounds and Sorafenib in the experiments with less toxicity.
[0000]
TABLE 35
Relative tumor reproduction rate of compounds and Sorafenib on human liver
cancer cell bel-7402 transplantation tumor model in nude mice T/C (%)
Relative tumor reproduction rate of compounds 1-10 and Sorafenib on human liver
cancer cell bel-7402 transplantation tumor model in nude mice T/C (%)
1
2
3
4
5
6
7
8
9
10
human liver
33.7
35.4
30.1
15.3
15.7
19.5
34.2
30.6
36.8
28.1
cancer cell
bel-7402
transplantation
tumor
11
12
13
14
15
16
17
18
19
20
human liver
23.7
31.6
29.8
36.1
33.6
14.9
12.5
12.7
16.3
17.2
cancer cell
bel-7402
transplantation
tumor
21
22
23
24
25
26
27
28
29
30
human liver
16.4
15.3
17.7
16.8
29.1
36.1
29.2
17.5
16.2
16.1
cancer cell
bel-7402
transplantation
tumor
31
32
33
34
35
36
37
38
Sorafenib
human liver
33.4
31.4
32.7
31.5
34.5
37.9
36.3
31.5
35.9
cancer cell
bel-7402
transplantation
tumor
Compound A′
Compound B′
Compound C′
human liver
37.2
30.4
32.6
cancer cell
bel-7402
transplantation
tumor
[0286] 11. Tumor inhibition rate of medicines on renal carcinoma cell line GCR-1 transplanted tumor model in nude mice
[0287] [Test animals] female BALB/cA nude mice, 35-40 days old, with weight of 18-22g. There were 12 mice in the negative conrol group and 6 mice in the treatment group.
[0288] [Test method] Take eugenic tumor tissues and cut into about 1.5 mm 3 , and then incoculate subcutaneously at the right armpit of nude mice under the sterile conditions. The diameter of the transplantable tumor in nude mice was determined with a vernier caliper, and the animals were divided into groups after the tumors were grown to 100-300 mm 3 .Using the method of measuring the tumor diameter, dynamically observe the antitumor effects of tested materials. The diameter of the tumor was determined three times every week and the mouse weight was weighed at the same time. The dosage of the medicine was 60 mg/kg, 6 times every week for 3 weeks. Sorafenib was oral administrated with dosage of 60 mg/kg, 6 times every week for 3 weeks. Equal amount of normal saline was administrated in the negative control group. Observe for one week after administration.
[Detection Indicators and Calculation Methods]
[0289] (1) Tumor volume (TV) is calculated as:
TV=1/2×a×b 2 wherein a and b respectively represents length and width.
[0292] (2) Relative tumor volume (RTV) is calculated as:
RTV=TV t /TV 0° wherein TV 0 is the tumor volume when administrated according to different cages (d 0 ) and TV t is the tumor volume measured each time.
[0295] (3) Relative tumor reproduction rate T/C (%) is calculated as follows:
[0000]
T
/
C
(
%
)
=
T
RTV
C
RTV
×
100
T RTV : RTV in the treatment group; C RTV : RTV in the negative control group. The test results used relative tumor reproduction rate T/C (%) as evaluating indicator of anti-tumor activity.
[0297] [Screening results] There was no mortality for the animals in the group of compounds and Sorafenib in the experiments with less toxicity.
[0000]
TABLE 36
Relative tumor reproduction rate of compounds and Sorafenib on human renal
carcinoma GCR-1 cell transplanted tumor model in nude mice T/C (%)
Relative tumor reproduction rate of compounds 11-20 and Sorafenib on human renal
carcinoma GCR-1 cell transplanted tumor model in nude mice T/C (%)
1
2
3
4
5
6
7
8
9
10
human renal
30.5
23.2
31.3
9.6
11.2
12.5
21.2
29.1
28.3
27.1
carcinoma
GCR-1 cell
transplanted
tumor
11
12
13
14
15
16
17
18
19
20
human renal
32.1
20.5
28.3
31.1
22.5
9.9
11.1
12.3
13.2
13.1
carcinoma
GCR-1 cell
transplanted
tumor
Relative tumor reproduction rate of compounds 21-30 and Sorafenib on human renal
carcinoma GCR-1 cell transplanted tumor model in nude mice T/C (%)
21
22
23
24
25
26
27
28
29
30
human renal
7.8
8.1
9.1
10.8
31.2
24.2
26.2
11.4
12.8
10.2
carcinoma
GCR-1 cell
transplanted
tumor
31
32
33
34
35
36
37
38
Sorafenib
human renal
31.4
32.5
33.4
36.1
32.3
25.9
32.3
20.5
33.9
carcinoma
GCR-1 cell
transplanted
tumor
Compound A′
Compound B′
Compound C′
human renal
34.2
30.4
35.6
34.2
30.4
carcinoma
GCR-1 cell
transplanted
tumor
[0298] According to the experimental results, the compound added with specific substituents in A ring have stronger anti-tumor activity than the compouns with no substituent or only amino formyl in A ring, especially the 4#-6# 16#-18# 19#-24# 28#-30# compounds have stonger anti-tumor activity which are stonger than the positive conrol Sorafenib, which have particularly evident effects on the tumor cell metastasis and tumor angiogenesis that are significantly stronger than Sorafenib. The test on normal human umbilical vein endothelial cells CCK8 found that these compounds have less toxicity to normal human cells like endothelial cells, which are relatively safe and reliable, but these compounds can achieve the antitumor activity through inhibiting the tumor angiogenesis. The in vivo transplantation experiments in nude mice showed that 4#-6# 16#-18# 19#-24# 28#-30# compounds have inhibition effects on human liver cancer and renal caner and their effects are better than Sorafenib, but these compounds have very significant effects on lung cancer and the effects obviously exceed the positive control medicine Sorafenib, which is an unexpected result.
[0299] The above results indicate that the compounds added with specific substituents in A-ring have more advantages than previously found compounds with no substituent or only amino formyl in A ring, and these new compounds have broader prospects in the treatment of cancer. | This present invention discloses a heterocyclic substituted acardite derivate and application thereof, namely compounds in the general formula (1) or the general formula (2) or pharmaceutically acceptable salts thereof, wherein A is monosubstituted or polysubstituted quinoline, isoquinoline, quinazoline, pyrrole or pyrimidine, and the substituent is halogen, C 1-5 alkyl, C 1-5 haloalkyl, C 1-5 alkoxy, C 1-5 haloalkoxy, C 1-5 alkylamino, C 1-5 haloalkylamino, amino or nitryl; R 1 is C 1-5 alkyl; R 2 is one or more selected from hydrogen, halogen, alkyl, alkoxy, haloalkyl or haloalkoxy; and R 3 is one or more selected from hydrogen, halogen, alkyl, alkoxy, haloalkyl or haloalkoxy. The compound of the present invention and the pharmaceutically acceptable salt thereof can be used for treating tumor or leukemia. | 2 |
The United States Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Contract No. DE-AC09-89R18035 awarded by the United States Department of Energy.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to the field of welding, and more particularly to welding brittle materials such as cast iron or stainless steel.
2. Description of Related Art
While many methods exist for joining metals together, welding is generally the most preferable because of the following reasons: 1) welding can be used with nearly all metals; 2) welding yields high-strength joints; and 3) welding avoids the galvanic-corrosion problems that can result from soldering or brazing. Metals that are not very reactive, such as steels, can be welded using a simple torch flame, often oxyacetylene, in air. More reactive metals require an electric arc in an inert atmosphere, such as argon, to prevent excessive oxidation.
In the welding process, adjacent regions of two or more discrete pieces of metal are locally heated to the point of fusion and then allowed to run together. Filler metal of similar composition is often added to the molten pool to bridge and unite the separate pieces when the melt cools.
Because welding involves the use of localized high temperatures, and because virtually all materials expand when heated, stress and/or distortion may appear in welded pieces as they cool. In relatively malleable metals, such as steel and wrought iron, this is not a problem since the metal is able to deform slightly and relieve the stress. Moreover, it is relatively simple to position the pieces before the main welding operation through small "tack welds" to minimize the overall distortion after welding.
Unfortunately, welding brittle metals poses a special problem. Examples of brittle metals include cast iron and stainless steel. In the nuclear industry, stainless steel can become highly embrittled through prolonged exposure to high levels of radiation. When such brittle metals cool after welding, the stress cannot be adequately relieved by deformation and cracking occurs instead. Attempts to repair the resulting cracks by further welding serve only to worsen the problem since the resulting stresses create new cracks or cause existing cracks to grow.
Traditionally, cast iron welders used a technique known as "peening" to minimize cracking from a weld. Using this technique, the welder simply taps the metal repeatedly with a hammer up and down the weld seam as it cools. Peening has been proven to be very effective in reducing cracking; however, the exact mechanism by which it works is far from clear.
Not wishing to be limited by this theory, one explanation for the success of peening is that the sharp acoustic waves launched into the metal provide the grain structure of the metal just enough extra energy to slip past each other and relieve stress. Both acoustic and thermal energy are in the form of phonons. However, the phonons resulting from acoustic energy are coherent, in phase, and travel in parallel. Conversely, the phonons resulting from thermal energy are incoherent and travel in random directions with random wavelengths. It is theorized that, due to their coherence, the phonons from peening become focused to relieve stress in the metal and therefore prevent cracking.
While traditional peening has been successful, its effectiveness is due in large part to the skill and intuition of the welder. Thus, for the technique to receive widespread acceptance, it must be refined to produce results that are both reliable and reproducible. Moreover, hazardous applications, such as those involving radioactivity, would require peening to be done remotely to minimize the welders' exposure to radiation.
Modern applications for peening have generally employed a vibrating member to impart the ultrasonic waves into the welded element. For example, U.S. Pat. Nos. 4,466,565 to Miyazima and 5,494,207 to Asanasavest both teach the use of vibrating members to assist in bonding wires on an integrated circuit board or chip. Similarly, U.S. Pat. Nos. 5,364,005 to Whelan et al. and 5,540,807 to Akiike et al. teach the use of a general purpose welding tool that incorporates a vibrating member to generate the ultrasonic waveforms. While these inventions are all useful for their intended purposes, they are not readily adaptable for use in hazardous environments and are generally geared toward micro-weld applications. Thus, there is room for improvement in the art.
SUMMARY OF THE INVENTION
One object of the present invention is to provide an apparatus that can apply an acoustic signal to a heated material to reduce stress and ultimately cracking as the material cools.
Another object of the present invention is to teach a method for applying the acoustic signal to the heated material.
A further object is that the apparatus be usable in hazardous environments, such as those involving radioactivity or toxic agents.
Yet another object is that the acoustic signal be of variable frequency to ensure that the optimum frequency signal for a given material is applied at least part of the time.
According to the present invention, the foregoing and other objects and advantages are attained by an apparatus including a variable frequency electric signal generator that is coupled to a transducer. The transducer produces a variable frequency acoustic signal in response to the variable frequency electric signal, which is then applied to the heated material.
In accordance with one aspect of the invention, the variable frequency electric signal is a square wave. The variable frequency square wave is generated as follows: A waveform generator produces a frequency control signal whose output is fed into a voltage controlled oscillator. The voltage variations in the frequency control signal produce an output signal from the oscillator of variable frequency. The oscillator output signal is then filtered through a clipping network to produce a variable frequency square wave. The square wave may then be amplified as desired for driving the transducer.
In accordance with another aspect of the invention, the transducer includes a piezoelectric crystal interposed between a countermass and a flexible bag holding a liquid. Excited by the variable frequency electric signal, the crystal will deform thereby generating acoustic waves that are transmitted to the heated material through the flexible bag.
The present invention provides a general purpose method and apparatus that can be used to apply a variable frequency acoustic signal to a heated material. The invention makes use of electronic components and can be applied without human proximity to the subject material.
Additional objects and advantages will become apparent from a consideration of the following description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an apparatus according to the invention.
FIG. 2 is a detailed block diagram of one embodiment of the invention that illustrates the components involved in generating a variable frequency square wave and the associated signals generated at various stages in the process.
FIG. 3 depicts the relationship between the triangle wave and the variable frequency square wave shown in FIG. 2.
FIG. 4 illustrates one embodiment of a transducer according to the present invention.
DETAILED DESCRIPTION
With reference to the figures, an apparatus that achieves all the various objects of the present invention will now be described.
FIG. 1 provides a high level overview of the two main components of the present invention: variable frequency signal generator 15 and transducer 30. During a manual peening process of cast iron, sound waves of varying frequencies are transmitted into the metal based on the position and/or thrust of the hammer. Since no scientific analysis is known to have been carried out to determine what frequencies are most effective for a given metal, temperature, thickness, etc., it is critical that transducer 30 produce acoustic signals of various frequencies. This ensures that the most effective frequencies will not be inadvertently omitted. To accomplish this, signal generator 15 can produce either a simple signal having a continuously varying frequency, or a complex tone containing many frequencies. Transducer 30 is designed to respond to the signal delivered from signal generator 15 by producing acoustic signals of like frequency, which are then transmitted into material 40. It is envisioned that modern data collection methods will allow a Fourier analysis to be performed on the waveforms transmitted through various materials to determine optimum frequencies for prevention of cracking. As these frequencies are discovered, signal generator 15 can be tuned to produce them depending on the particular application.
Signal generator 15 is coupled to transducer 30 via cable 20. Cable 20 must be of sufficient quality to minimize signal degradation, particularly in applications involving hazardous conditions. For example, when radioactivity is involved, it is preferred to limit exposure to just cable 20 and transducer 30 for the protection of the welder and the electronic components. Thus, cable 20 may in some circumstances be quite lengthy. Transducer 30 will commonly be manipulated by a mechanical arm or carriage for safety purposes.
FIG. 2 depicts a preferred embodiment of the present invention where a variable frequency square wave is produced for driving transducer 30. In this embodiment, signal generator 50 is used to produce triangle wave 55 for input to voltage controlled oscillator 60. A triangle wave is chosen because, as will be discussed in reference to FIG. 3 below, it will ultimately produce a square wave whose frequency varies linearly. Nevertheless, any alternating current waveform will suffice. Voltage controlled oscillator 60 produces oscillator output signal 65 that varies in frequency in direct relationship to triangle wave 55 applied to its input. Because oscillator output signal 65 may contain sharp voltage peaks depending on the type of oscillator used, oscillator output signal 65 is preferably filtered through peak clipping network 70 to form standard square wave 75.
The relationship between triangle wave 55 and square wave 75 is shown best in FIG. 3. When triangle wave 55 is at low voltage point 56, square wave 75 is running at its slowest frequency corresponding to reference numeral 76. Similarly, when triangle wave 55 is at high voltage point 57, square wave 75 is running at its highest frequency corresponding to reference numeral 77. Because triangle wave 55 changes voltages linearly, the variations in frequency produced by voltage controlled oscillator 60 are also linear. It should be readily apparent that a non-linear waveform chosen for input to voltage controlled oscillator 60 will produce non-linear frequency variations in square wave 75. In the preferred embodiment, the frequency of square wave 75 should vary between 5 kHz and 20 kHz.
Once square wave 75 emerges from clipping network 70, it is usually fed through amplifier 80 to produced amplified square wave 85 that is suitable for transmission over cable 20 to transducer 30. Preferably, the voltage levels of square wave 85 are chosen so that the output power required is in the range of 100 watts.
Turning next to transducer 30, FIG. 4 provides a cut-away view of the internal components of a preferred transducer according to the present invention. Transducer 30 is comprised of low-density housing 90 having open end 90 o and closed end 90 c . Countermass 100 is lodged in closed end 90 c and flexible bag 120 is held in open end 90 o . Piezoelectric crystal 110 is held between countermass 100 and flexible bag 120. Crystal 110 is electrically connected to cable 20 through housing 90. In the preferred embodiment, crystal 110 is made from lead-zirconium titanate. Application of an electrical signal to crystal 110 through cable 20 will cause rapid deformations in crystal 110 in relationship to the frequencies contained in the applied signal. These deformations are acoustically coupled to material 40 through flexible bag 120.
Flexible bag 120 is filled with dense liquid 130 that will neither freeze nor boil over the expected range of temperatures of use. Mercury can be used for dense liquid 130; however, because of Mercury's toxicity, a compound consisting of gallium (70% by weight), indium (24% by weight), and tin (6% by weight) is preferred. The cover of flexible bag 120 should be made from a heat resistant material that will retain the type of liquids discussed above. Fiberglass cloth impregnated with silicone rubber has proven effective for this purpose.
For maximum effect, the acoustic signals generated by deformations in crystal 110 are passed substantially through flexible bag 120 and into material 40. Acoustic losses will be minimized if the acoustic impedance of transducer 30 is matched to material 40. A discussion of acoustic impedance and its significance is contained in U.S. Pat. No. 5,251,490 to Kronberg and is incorporated herein by reference. Nevertheless, it has been found that flexible bag 120 and liquid 130 form a continuous acoustic path between crystal 110 and material 40 so that acoustic losses are minimal.
The above description is given in reference to an apparatus that can apply a multi-frequency acoustic signal to a heated material to reduce stress and ultimately cracking as the material cools. However, it is understood that many variations are apparent to one of ordinary skill in the art from a reading of the above specification and such variations are within the spirit and scope of the invention as defined by the following appended claims: | An apparatus and method for reducing cracking in a heated material as the material cools. The apparatus includes a variable frequency electric signal generator that is coupled to a transducer. The transducer produces a variable frequency acoustic signal in response to the variable frequency electric signal, which is applied to the heated material to reduce cracking as the material cools. | 1 |
This is a continuation of application Ser. No. 937,416, filed Dec. 3, 1986, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to a cantilever mount of a substrate lamina of a surface wave device wherein the device may be generally triangular shaped and is attached to a base along one edge thereof and wherein its point which extends from said edge of attachment is mounted above the base so that it can freely move.
2. Description of the Prior Art
Surface wave components are known which may be filters, resonators and/or delay lines. The significant features of such components comprise a transducer and/or reflector structures which are arranged on the surface of the substrate plate so as to essentially define the prescribed properties of the component. The structures may be strip-shaped finger electrodes and/or reflector strips attached to the surface as well as auxiliary structures such as pads, or shielding electrodes. Electrically, non-conducting etched structures of the substrate surface are also standard for reflector structures instead of metallic strips.
Such a substrate lamina of, preferably, quartz, lithiumniobat, lithiumtantalat and the like is normally held on a support and is accommodated in a housing, where an adhesive means is provided for mounting and is arranged between the back surface of the substrate lamina on the opposite side of the wave components and the support. Generally, the adhesive extends over the entire surface of the back surface of the substrate lamina so as to provide a tight attachment of the substrate lamina to the support.
An adhesive means which is relatively plastic is the preferred means of attaching such lamina to a support so that the stresses occurring due to temperature changes for example, in the support are isolated from the substrate lamina. Gaseous discharge from such a viscous adhesive combined with the corresponding precipitate on the substrate surface of the substrate lamina carrying the structures have been assumed as the reasons that disturbances occur which have occurred in the past, but these cannot be eliminated using glues having less solvent or less softener and which are harder have also been employed.
Disturbances occur to a noticeable degree particularly in narrow band filters and resonator components and/or delay lines where the disturbances are based on mechanical movement which originate from housing parts, for example.
U.S. Pat. Nos. 3,753,164 and 4,450,420 disclose surface wave filters having trapezoidal or triangular-shaped substrate lamina. The shapes selected serve the purpose for reducing reflections and of saving substrate material. The employment of a substrate body having a triangular shape is known from the publication 1983 Ultrasonics Symposium, page 268, FIG. 4. This article discloses a dynamometer having a surface wave structure mounted on the surface of the substrate body. This structure supplies the output measured variable. The surface wave structure is at least substantially placed therein as shown in FIG. 4 close to the edge of the three-sided substrate body where the substrate body is held. The point lying opposite the mounting is largely free of a structure.
European Patent Application Publication No. 0 156 502 discloses a surface wave arrangement having a rhombic shape. The rhombus is held in its middle region which is where the main part or the defining part of the surface wave structure is located. "Defining part" is defined as those parts of the transducers and/or reflector structure which significantly define the prescribed properties of the surface wave device. The central position of such a structure thus determines a certain limiting region from which the defining properties of the structure greatly diminish relative to the center of the structure toward the end which is held.
SUMMARY OF THE INVENTION
The present invention provides a cantilever mounting means of the substrate lamina of a surface wave component which may be a narrow band frequency precise filter or a resonator or a delay line wherein the substrate lamina is mounted on a base with an adhesive between the substrate lamina and the base and whereby the transducer and/or reflector structures mounted on the substrate surface which significantly define the properties of the component are arranged such that the substrate lamina is tapered with respect to its surface so that the substrate lamina has a broad first end and a narrow opposite end and adhesive means is located only in the region of the first end of the substrate lamina and only extends maximally up to about the middle position of the defining structure lying closest to the first end on the substrate surface and wherein the second end of the lamina is free floating so that mechanical distortions of the material of the substrate lamina which could act on the substrate lamina in the regions of the structures mounted on the surface are minimized.
The acute or obtuse conical substrate lamina used in the invention are held at its broad first end which does not extend further than at most up to the central position of the first defining structure and is held for example, with an adhesive. According to the invention, the significant parts of the overall surface wave structure of the component extend over the region of the opposite end of the wedge-shaped substrate lamina even though the substrate lamina is inherently extremely sensitive to flexations in the region of this end of the "wedge". With surface wave component having this selected shape and with placement of the transducer structures in the region of the end opposite to the support mounting, the flexations of the substrate lamina which are anticipated on the basis of a merely single sided mounting surprisingly have little disturbing effect on the properties of the component of the invention. The invention allows surface wave components mounted on substrate lamina to be produced which have minimum disturbances and much less than those of the prior art devices.
A preferred shape of the substrate lamina of the invention for a surface wave component is that of a wedge having a surface which is shaped as an equalateral triangle having acute angles of 60°. One side of the triangle is a first end and extending from this first end which is attached to the base, the substrate lamina extends cantileverly up to its opposite second end which is one of the apexes of the triangle. The surface wave structure is mounted along the longitudinal extent and extends as far as possible into this apex which is the region which is as far as possible from the mounting point.
Other objects, features and advantages of the invention will be readily apparent from the following description of certain preferred embodiments thereof taken in conjunction with the accompanying drawings although variations and modifications may be affected without departing from the spirit and scope of the novel concepts of the disclosure and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a preferred embodiment of the invention;
FIG. 2 illustrates in plan view a modified form of the invention; and
FIG. 3 is a schematic view showing how a plurality of components according to the invention of embodiment of FIG. 1 can be manufactured.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a substrate lamina 42 in plan view mounted on a base 41. The thickness of the substrate lamina 42 is uniform throughout its area. The substrate lamina 42 may be composed of, for example, lithiumniobate or lithiumtantalate. The plan surface shape of the substrate lamina 42 is for example, an equilateral triangle as shown.
Two interdigital structures such as 51 and 52 are formed on the substrate lamina 42 and can be employed as input and output transducers of the components. Associated reflector structures 53 and 54 are also formed on the substrate lamina 42. The structures 51, 52, 53 and 54 are arranged in line as shown.
As can be seen from FIG. 1 the structures 51, 52, 53 and 54 extend far into the right-hand apex and far into the end 46 of the substrate lamina 42. In particular, the reflector structure 54 is formed of strips or, respectively, fingers which become shorter toward the last finger 154 to accommodate the reduction in the width of the substrate lamina 42. A corresponding shortening of the fingers of the reflector structure 53 is also preferably provided so that the last finger 153 of the reflector structure 53 is also relatively short.
The substrate lamina 42 is mounted on a base or foundation 41 of which only the contours are shown in the form of broken edges. The base or foundation 41 is mounted in a housing (not shown) together with the substrate lamina 42.
As previously discussed, the substrate lamina 42 41 is attached to the base 41 at only one first end 45. The first end 45 is the neighboring region of the triangular edge 145 of the substrate lamina 42. Joining means such as an adhesive are used for mounting the substrate lamina 42 to the foundation 41 at its first end 45. The adhesive 43 is mounted between the underside of the substrate lamina 42 and the upper side of the base 41 is indicated in the drawing. The thickness of this layer of adhesive 43 mounted between the substrate lamina 42 and the base 41 is selected to have a dimension such that the entire substrate 42 floats free or projects freely above the foundation 41 with a substantial portion outside of the region 143 of the adhesive 43. The position of the boundary 145 of the adhesive 43 is important since its position relative to the reflector structure 53 is significant. The boundary 145 on the underside substrate lamina 42 can extend into the region or, respectively, up to the defined middle position of the reflector structure 53.
The structures 51, 52, 53 and 54 and particularly the reflector structures 53 and 54 are structures which significantly define the properties of the components. For example, they define the resonant frequency, the band width and other characteristics of a filter. However, generally the conditions of those parts of the reflector structure 53 and the reflector structure 54 lying further toward the outside as seen from the center of the structures 51-54 are less important and their effect diminishes at the outer edge as far as changing the defining properties. Thus, for example, that part of the reflector structure 53 comprising the last finger 153 lying to the left of the boundary 145 in FIG. 1 determines the properties of the entire filter only to a very small degree. In a corresponding manner, the reflector structure 54 may also be designed with fingers having lengths which decrease toward the second end 46 of the substrate lamina 42.
In the invention, the structure substantially defining the properties of the component are placed on the substrate lamina with an asymmetrical arrangement on the surface of the substrate.
As an example, an adhesive which is referred to as hard glue is employed as the adhesive 43. Pre-cross-linked epoxy resins and polyimides are particularly suitable as the adhesive 43. It is beneficial to use an adhesive which does not flow very much. However, other means of attachment such, as for example, glass solder, bonding, alloying and other attachment means can also be employed to join the substrate lamina 42 to the base 41. For this purpose, layers, preferably layers of metal, are applied to the substrate lamina 42 and/or to the base 41 before joining and are placed in the region 143 provided for the adhesive 43 for the mounting of the first end 45 of the substrate lamina 42. The attachment can be effected with this layer or these layers. Expediently, the connection is also a hard connection in the present invention. With the dimensions of the invention such as shown in FIG. 1, it is not only achieved that the flections of the foundation 41 coming from the housing such as particularly temperature change flections cannot effect the prescribed properties of the component, but it is also achieved that jaring concussions to the component do not exert any disturbing influences due to the single side mounting even though the structures 51 through 54 are mounted on the substrate lamina 42 in a region which can flex.
Dampening compounds 57 and 58 of a standard type are also mounted between the lamina 42 and the base 41.
A finger structure located in the region 143 of the attaching means 43 is schematically indicated by 55. The structure 55, however, is a non-defining structure for the properties of the component. Such structure 55 can, for example, be a further output transducer for a control signal and has no effect on the property defining structures 51 through 54.
It is possible that the substrate lamina 42 may lightly lie against the surface of the base 41. Preferably, however, a small distance and an air gap is provided between the substrate lamina 42 and the foundation 41. In particular, the damping compound 58 should not cause an attachment to the foundation 41 which opposes the objects of the invention.
FIG. 1 illustrates dimension a and a' between the edge 142 and the last finger 153 of the structure 53 and these dimensions are noticeably greater than the dimension b between the last finger 154 of the structure 54 and the apex 46 of the substrate lamina 42. This enables a firm mounting of the substrate lamina 42 by means of, for example, the adhesive 43 on the foundation 41.
As stated above, the edge 145 can maximally extend up to the middle position of the structure 53 as indicated by the dashed line in FIG. 1. The dotted line 245 indicates a position of the edge of the adhesive 43 which is also according to the invention. Which exact position of the edge between 145 and 245 is selected does not effect the invention. A shortening of the length a to a' reduces the width of the region 143 of the mounting means. In this manner, the increasing of the length a up to the boundary 145 offers advantages without significantly reducing the properties of isolating the lamina 42 from disturbing influences.
The substrate lamina 42 according to the invention may have the following dimensions such as, for example, the length between the edge 142 and the end 46 may be 6 mm and the length a may be 0.5 through 1 mm. The air gap between the bottom surface of the lamina 42 and the foundation 41 may be in the range from a micron to a few tenths of a millimeter.
FIG. 2 illustrates another example of the invention wherein the substrate lamina 42' is formed in the shape of a truncated wedge which has its apex end 46 cut off at its second end. The other arrangements are substantially as shown in FIG. 1.
FIG. 3 illustrates a portion of a substrate plate 420 comprising a plurality of substrate lamina 42 on which the structures 51 through 54 are merely suggested. The dashed lines extending diagonally and vertically and illustrate the cuts that are made so as to form the individual substrate lamina 42 illustrated in FIG. 1.
Although the invention has been described with respect to preferred embodiments, it is not to be so limited as changes and modifications can be made which are within the full intended scope of the invention as defined by the appended claims. | A cantilever mount for a substrate lamina of a surface wave device wherein the substrate lamina 42 of the component is attached only at its one end 45 and is a wedge-shaped structure. The tapered end 46 of the substrate lamina 42 which is remote from the atachment location is mounted above the surface 41 of the base plate 41 which causes minimization of disturbing influences. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is the United States national phase under 35 U.S.C. §371 of PCT international application no. PCT/EP2012/000956, filed on Mar. 2, 2012.
BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments relate to methods for automatically licensing features during the upgrade of a first communication system to a second communication system, a computer program and a licensing system to perform such method.
2. Background of the Related Art
Modern communication systems such as telephone systems for small, medium and large enterprises are configurable and scalable in many ways, for example using CTI (Computer Telephony Integration) and CSTA (Computer Supported Telecommunications Applications). Mostly, the determined features are activated by means of a file containing licensing data.
A change in the scope of features to be licensed is often associated to the upgrade of such a system. The reasons for this can be legal reasons (for example, required royalty payments to licensors), economic reasons (for example, if customers are to pay for a feature in a new version) or technical reasons (for example in old versions, as many TDM as available ports could connected while for a new system, a license is required for each TDM device). TDM stands for Time Domain Multiplex and refers to a telecommunication device which uses a time multiplex procedure as for example in “conventional” devices such as wireless phones, but not as in IP phones.
According to internal company procedures, the upgrade of telecommunication systems may typically be carried out manually according to the following procedure:
1. A special user (who in many cases is a product manager or PM) acquires a quantity of licenses also known as PM-licenses for new systems using standard procurement procedures. Different scenarios for “New Systems” are possible: It can be the hardware of a legacy system on which new software or new software features are updated or upgraded. It can be as well the use of new hardware which can operate new software with newly licensed features.
2. As a further step of the ordering procedure the license fees are paid.
3. After the ordering process is completed, the licenses become available on the PM's account.
4. Whenever a customer wants to upgrade an old system, he sends to the PM a proof of the presence of the features on the old system. This proof can be provided in the form of screenshots, a delivery slip for the TDM devices or the like.
5. The PM sends the new licenses manually to the customer's account.
6. This customer will then activate the new licenses.
The procedure described above has a number of disadvantages:
1. The PM must in each case estimate in advance how many are needed.
2. The royalty payment is made before the actual use or activation of the licenses, which is sooner than required.
3. Generally, the licenses are not immediately available, since the ordering process takes some time.
4. The required evidence is not safe and there is room for abuse.
5. It can be impossible or very difficult to ensure that new licenses are not enabled on systems that have not been upgraded. In other words, it is difficult to prevent that such licenses are used to upgrade an existing communication system on which no “old” license or software was installed and to configure and activate it as functional system.
Another fundamental problem is that the upgrade is a manual process requiring a significant effort and thus generating significant training and implementation costs as well as costs to correct errors and avoid errors.
BRIEF SUMMARY OF THE INVENTION
We provide a method for automatically licensing features during the upgrade of a first communication system to a second communication, a corresponding computer program, and a corresponding licensing system.
According to an embodiment of the invention a computer aided and computer-based method for automatically licensing features during the upgrade of a first communication system to a second communication system (where the first communication system does not necessarily have to be different from the second one in terms of hardware or software) includes the following steps: first, the features that need to be licensed are extracted from a database. This database can be built, for example, from existing features in the first communication system. Then, the features which have to be licensed are transmitted to a license server and a license file is created, which is then transmitted to the second communication system and is installed there also.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows schematically the components of a license system according to an exemplary embodiment of the invention and FIG. 2 illustrates a flow chart of an exemplary embodiment of a method for automatically licensing service features during the upgrade of a first communication system to a second communication system.
DETAILED DESCRIPTION OF THE INVENTION
The method according to the invention replaces the usual manual workflow with an automated procedure. The method can be executed in a simple and cost-effective manner, and it eliminates the need for licenses that are used later to be purchased and paid for in advance. By extracting the features to be upgraded from existing databases and by transferring them to the license server, a simple and automated procedure is ensured.
According to an advantageous embodiment of the method, the step of extracting the features to be licensed from the database comprises a step of reading the features of the first communication system and depositing the data in a customer data memory. Thus, these data and features can be transferred as a compact unit, which can for example be done in binary format by means of an appropriate software tool.
It is advantageous to convert the content of the customer's data memory and to expand it with further information, such as, for example, as given by means of the MAC address. Furthermore, it is advantageous if the step of transmitting the features that need to be licensed to the license serve comprises a step of transmitting the converted content of the customer data memory to the second communication system, and in addition a step of generating and transmitting an inventory file to the license server. All the customer data (at least the essential customer data) are included as an “Inventory” for example in this inventory file. The security of the transmission and the protection against fraud can be substantially increased if the inventory file is cryptographically signed.
A particularly simple and safe process implementation is possible because a License Authorization Code is entered on the license server. This license authorization code specifies and determines the licensed features, and also which features need to be upgraded. The License Authorization Code can be used for an order to upgrade a version or to acquire additional licenses.
It may be advantageous if the license server could check first whether or not the first communication system is upgraded. So it can be prevented that an old system without any license would be upgraded through an upgrade license.
Furthermore, it may be advantageous that the license server runs a verification step to prevent another upgrade of a second communication system. This means that for example, when replacing old hardware with new hardware, systems cannot be upgraded via the license server. To this end, a lock table is created, and by doing so, the MAC address of the old hardware, that has to be retired and replaced with new hardware, is captured which prevents the upgrade of the old hardware with an upgrade license. This greatly reduces possible fraud.
Embodiments may also provide a computer program or computer program product according to claim 9 for carrying out any of the methods described above. The advantages and characteristics associated to the methods previously described are similarly applicable to the computer program, an therefore no separate description is provided.
Embodiments may also provide a licensing system. Such a licensing system includes a first communication system, a second communication system (which must not necessarily be different from the first communication system in terms of hardware and/or software), as well as a license server. The advantages and characteristics of the licensing system according to the invention are similar to those previously described with regard to the methods and are therefore not described again.
As already mentioned, no upfront licenses are required by the method and the computer program and licensing system according to the invention, which is why the royalty payment to the licensor does not take place until the date on which the licenses are needed. It is also possible that an upgrade may optionally be carried out without ordering licenses, provided this is allowed by the system. This would be the case, for example, that when switching to new hardware, the new or additional licenses will be provided free of charge.
It should also be noted that all transactions are documented and can be easily understood. The inventory file includes all previous features (excluding the upgrade newly added features.)
According to the invention it is thus possible to prevent in a simple way that new licenses are activated on systems that were not upgraded since proof of the presence on the old systems must first be provided.
Further advantages, features and characteristics of this invention will become apparent from the following description of an advantageous embodiment of both the method and the licensing system that can be appreciated from FIGS. 1 and 2 .
The license system 10 comprises a first communication system 11 and a second communication system 12 that are shown. The first communication system 11 is an old system and the second communication system 12 is a new one which includes hardware changes. As already stated, the two communication systems 11 , 12 can be the same and only differ in software and/or licenses.
A telecommunication system called OSO MX V3 by Siemens Enterprise Communications is used as an example for the first communication system 11 , while the next generation communication system called Next-GenSME is used as an example for the second communication system 12 . An application 14 for the administration of customer data (“ManagerE”), reads the customer data on the first communication system 11 and stores it in so-called customer data memory KDS. This KDS customer data memory is then transferred as a binary file to the ManagerE. Here are stored the number of the features that have not been licensed on the first communication system 11 , but that are defined by means of other features (e.g. a proper hardware system). In this example it is the number of physically installed TDM devices or TDM users. This feature previously available for free should be considered as part of the version upgrade since it needs to be licensed on the new version of the product (NextGenSME, for example).
The number of features that must be upgraded (e.g. TDM users) is determined from the customer data memory by using a KDS-conversion. Here, the customer data include additional information (in particular the MAC address of the system they belong to.)
The converted content KDS' of the customer data memory KDS is transferred to the second communication device 12 . A so-called inventory NV file is generated in the second communication system 12 and cryptographically signed.
The Inventory file NV is transferred to the license server (also called Central License Server) CLS using the WBM/CSCM interface for online licensing via the Internet. WBM stands for Web-Based Management, which is used for the administration of a communication system 11 or 12 on a web server with an interface to a browser. CSCm stands for Customer Site Components modular, which is an interface between the WBM and the license server and is used to establish a connection to the license server for the online licensing procedure. A license file LF is downloaded from the license server CLS and the content of the loaded license is displayed in the WBM. In addition, a license authorization code LAC is entered via the WBM. A license order for a version upgrade and optionally for additional licenses is issued. To ensure that the inventory file was not tampered with, the license server CLS can verify the signature and also ensure by means of the MAC address in the transferred Inventory File and of a revocation list created in a database DB that the original system has not been upgraded yet. The presence (payment) of the available licenses required for the planned upgrade can be checked by means of the transmitted License Authorization Codes LAC. The license server CLS generates the license file LF for the second communication system 12 taking into account the data in the inventory file, as well as the purchased licenses that are referenced via the License Authorization Code LAC. To avoid a further activation of the Inventory INV files on another system or in another communication system, the license server CLS records the MAC address from the Inventory file in the revocation list. In case of an attempt to upgrade a communication system whose corresponding MAC address is listed in the revocation list, an error message appears, and the licensing process is canceled. This greatly enhances the security and protects against fraudulent licensing.
The generated license file LF (also called license data) will be sent via the Internet interface to the second communication system 12 where it is installed. Subsequently, the second communication system 12 can be used with all the upgraded features.
It should be noted that the described features of the invention with reference to the illustrated embodiment of the invention, such as sequence and exact execution of the individual method steps and the software and hardware components used, may be present in other embodiments and, except when otherwise indicated or prohibited for technical reasons. | The invention relates to a method for automatically licensing service features during the upgrade of a first communication system ( 11 ) into a second communication system ( 12 ), said method having the following steps: (a) extracting the service features to be licensed from a database, (b) transmitting the service features to be licensed to a License Server (CLS), (c) generating a license file (LF) in the License server (CLS), (d) transmitting the license file (LF) to the second communication system ( 12 ), and (e) installing the license file (LF) in the second communication system ( 12 ). This invention also relates to a corresponding computer program and corresponding licensing system. | 7 |
TECHNICAL FIELD
[0001] The present invention relates to wound dressings, particularly an adhesively applied bandage adapted for use on the lip and/or (alar sidewall of the) nose.
BACKGROUND ART
[0002] The popularity of the adhesive bandage, originally patented in 1929, is not surprising as it provides many known advantages such as protection, controlled wound environment, and concealment. As described at length in U.S. Pat. No. 7,943,811, there has since been patented many types of “improved adhesive bandages” which among many advantages, promote healing by incorporating, for example, an antibiotic agent. Various forms (like those adapted for use on fingertips) and categories (like those created to optimize moisture retention/absorption), have also been invented, in some cases by adding additional layers to the composed bandage.
[0003] Still, an adhesive bandage generally comprises a first layer (base sheet) for covering the wound site and an area around the wound site and onto which an adhesive is incorporated to secure it and at least one optimally non-adhering second layer (dressing) for placement immediately over the wound and coming into contact with the wound. The dressing is smaller, by varying percentages, than the base sheet.
[0004] The application of an adhesive bandage onto the nose (mainly, the alar sidewalls) and/or lips (and that area immediately surrounding the lips) has presented a challenge to those desiring the advantages (both therapeutic and aesthetic) of covering wounds there located.
[0005] U.S. Pat. No. 4,534,342 describes a nose bandage that envelopes the entire nose. While this bandage may address coverage of a wound located on the exterior of the alar sidewall, it does not address those located on the inside and/or towards the edge of it. Further, it offers very little inconspicuousness and is most likely practical only in clinical settings.
[0006] U.S. Pat. No. 1,111,679 describes a bendable clip (of unspecified composition) that holds non-adhesive dressings in place, with this assembly being further secured by adhesive tape. The use of this combination of items, by today's standards, would prove cumbersome and inconvenient.
[0007] In the case of a conventional two-ended adhesive bandage, the inability to apply (and/or the undesired result of applying) one of the two adhesive ends onto the mucosal tissue of the inside of the lips and/or nose prevents its effective use.
[0008] In the case of non-adhesive wound dressings (such as gauze or absorbent pads) used in conjunction with separate adhesive tapes, a similar problem exists and the alternative is to wrap the entire head of the person with securing devices, which is impractical for all but clinical settings and generally an unwelcomed solution.
[0009] The American Sexual Health Association (ASHA) reports that more than 50% of American adults are infected with the herpes virus that causes cold sores or fever blisters. Currently, the options for “covering” and “protecting” these sores and blisters are limited to products called cold sore “patches” or “bandages” which are generally small, circular coverings with the entire surface of the layer next to the skin being cohesive. That is, the “patch” sticks to the sore risking re-injury upon removal.
SUMMARY OF INVENTION
[0010] In a first aspect, the present invention solves the problem of attachment of a bandage to the lip and/or area surrounding the lip and/or (alar sidewall of the) nose by incorporating a malleable component or material into an adhesive bandage so as to enable the user to affix the bandage by wrapping the bandage around the lip and/or alar sidewall of the nose (with one end being just inside of the lip or nose and the other end being adhesively attached to the skin) and applying gentle force to said malleable component to form it to the shape of the lip or nose.
[0011] In a second aspect, the present invention solves the problem of attachment of a bandage to the lip and/or area surrounding the lip and/or (alar sidewall of the) nose by incorporating a mucosal adhesive to that end of the adhesive bandage intended for inside of the mouth or nose so as to enable the user to adhesively attach said end to the inside of the mouth or nose and then attach the other end to the skin.
[0012] In a third aspect, the present invention solves the problem of attachment of a bandage to the lip and/or area surrounding the lips and/or (alar sidewall of the) nose by creation or incorporation of some combination of the aforementioned malleable component or material and mucosal adhesive.
[0013] In a forth aspect, the present invention solves the problem of attachment of a wound dressing to the lip and/or mouth area and/or nose of any non-human animal by using the spirit of the invention in an iteration suitable to the skin and mucosal tissue of the non-human animal.
[0014] In another aspect, the present invention relates to a cosmetic method for concealing wounds by using a combination of at least one of the above described lip and/or nose bandage iterations along with commercially available cosmetics (makeup) and stains of various lip tones. Such iteration comprises a base sheet fabricated of a material optimized for the acceptance of such cosmetics so as to camouflage the bandage itself.
[0015] In another aspect, the present invention relates to an inconspicuous bandage for concealing wounds by creating at least one of the above described lip and/or nose bandage iterations comprising a transparent base sheet and a dressing in one or more skin-toned colors.
[0016] In another aspect, the present invention relates to a kit containing several of the lip and/or nose bandages together with various medicaments appropriate for treating each stage of wound development/healing, for example, the blister stage, ulcer stage and scabbing stage of a herpetic cold sore, wherein said medicaments are either contained separately and applied to the bandage or wound by the user or alternatively, associated with the dressing during manufacturing so as to be transferred either immediately or over time from the dressing to the wound upon contact with the wound.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1 is a perspective view of a human nose with a wound located on the exterior of the alar sidewall.
[0018] FIG. 2 is a perspective view of a human nose with a lip and/or nose bandage in accordance with the present invention secured to the alar sidewall.
[0019] FIG. 3 is a perspective view of a human mouth with two (2) lip and/or nose bandages in accordance with one embodiment of the present invention secured to the upper and lower lips.
[0020] FIG. 4 is a perspective view of a human mouth with two (2) lip and/or nose bandages in accordance with another embodiment of the present invention secured to the upper and lower lips.
[0021] FIG. 5 is a schematic perspective view showing the components of the lip and/or nose bandage according to a first embodiment of the present invention.
[0022] FIG. 6 is a schematic perspective view showing the components of the lip and/or nose bandage according to a second embodiment of the present invention.
[0023] FIG. 7 is a schematic perspective view showing the components of the lip and/or nose bandage according to a third embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0024] As used herein, the term “wound” is intended to include all wounds (surgical or traumatic), scratches, sores, cold sores, blisters, fever blisters, ulcers, pimples, lesions, and burns.
[0025] As used herein, the term “bandage” is used interchangeably with “wound dressing” and refers to a covering to be placed over a wound.
[0026] Examples of embodiments of the invention are set forth below and reference is here made to each example. Examples are provided by way of explanation and not limitation of the invention. The spirit of the present invention is a bandage that will wrap and/or form and/or mold around the edge of the alar sidewall of the nose and/or around the upper or lower lip and remain affixed through a combination of the means herein referenced. It will be apparent to those of ordinary skill in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. It is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and equivalents.
[0027] A lip and/or nose bandage 13 in accordance with the present invention is illustrated generally in FIGS. 2 and 3 and 4 . In FIG. 2 a lip and/or nose bandage 13 is shown secured to a nose 6 and in FIGS. 3 and 4 , to the upper and lower lips 11 of a wearer.
[0028] FIG. 1 shows a wound located on the exterior of the alar sidewall 9 of the nose. (It is also common for a wound to be similarly located on the interior of the alar sidewall of the nose.) FIG. 2 illustrates that in both circumstances, a lip and/or nose bandage can be used to cover both wound(s). This example shows a first end 8 {referred to hereafter as the external end ( 8 )} conventionally adhesively attached to the skin. FIG. 2 further demonstrates an example of a lip and/or nose bandage 13 as it would appear on a user once applied, that is, wrapped 12 around the edge of the alar sidewall of the nose. FIGS. 3 and 4 show examples of a lip and/or nose bandage 13 as they would appear on a user once applied, that is, wrapped around the upper and/or lower lip(s) 11 .
[0029] The lip and/or nose bandage can be made in many sizes to accommodate various sized wounds as is commonly practiced with production of adhesive bandages. In a preferred embodiment, as illustrated in FIG. 5 , a lip and/or nose bandage measured at the named x-axis 21 can range in width between 7 and 30 mm and as illustrated in FIG. 7 , in length (measured at the named y-axis 22 ) between 30 and 50 mm.
[0030] [ 0030 ]In FIGS. 2 and 3 and 4 , the external end 8 of the bandage is adhered to the skin. The second end 10 {referred to hereafter as the internal end ( 10 )} is affixed by at least one of three means; one means incorporates a malleable component (see FIG. 5 ), the second means incorporates a mucosal adhesive (see FIG. 6 ), and the third means is a combination of the malleable component and the mucosal adhesive (see FIG. 7 ). Reference now will be made in detail to these means.
[0031] As seen in FIGS. 5 and 6 and 7 , all embodiments of the lip and/or nose bandage comprise a dressing 14 layer (that layer coming in contact with the wound) having a skin facing side 15 and a top side 16 and a base sheet 18 layer having a top surface 19 (that side seen by the user once applied) and a bottom surface 20 . The dressing 14 can be made of many materials known to the art, for example, those which control moisture at the wound site or those which contain releasable medicaments and in all cases is desirably non-adherent, such as the HURT-FREE® dressing used in the Comfort Sheer BAND-AID® adhesive bandage. The base sheet 18 can be made of many materials known to the art, for example, those featuring higher levels of breathability and/or elastic properties. Given the multidirectional movement of that area surrounding the lips of a person engaged in speaking or eating, for example, the base sheet 18 is preferably elastic and highly flexible, such as the COMFORT-FLEX® base sheet used in the Comfort Sheer BAND-AID® adhesive bandage.
[0032] FIG. 5 shows a first embodiment of the present invention wherein a malleable component 23 is sandwiched between the dressing 14 and base sheet 18 . The malleable component 23 can be made of any material capable of being easily wrapped and molded or formed into a desired shape, for example, by a thumb and forefinger, around a lip or alar sidewall and holding that shape. Additionally, the component is desirably produced from a material both economical and safe to use. The malleable component 23 can be incorporated as at least one strip 24 , wire, or sheet 25 cut to a width and length appropriate to the width and length of the bandage. For example, three (3) lip and/or nose bandage prototypes (18 mm) in width were produced with favorable results using 1)an uncoated 0.5 mm metal wire, 2)a plastic-coated 1 mm metal wire, and 3)a 10 mm wide aluminum polylaminate. In a preferred embodiment, pure tin sheet (such as is known in the wine-making industry as the ideal material for bottle capsules) can be cut to occupy a surface area of at least 50% of the width and 60-70% of the length of the dressing. A bonding process such as that one used to sandwich plastic strips between the backing layer and the adhesive layer of Breathe Right® nasal strips may be used to bond the top side 16 of the dressing 14 to the bottom surface 20 of the base sheet 18 with the malleable component 23 sandwiched there between. A skin-friendly (biocompatible) adhesive, such as the high-tack adhesive Wacker Silpuran 2117, can be applied to all or some part of that area of the bottom surface 20 of the base sheet 18 demonstrated by the shaded section 26 on the external end 8 of the base sheet 18 . That area 28 of the dressing 14 distinguished from the rest of the dressing by a dotted line may be cut away (as part of the manufacturing process) so as to match the area of application of skin adhesive on the bottom surface 20 of the base sheet 18 .
[0033] FIG. 6 shows a second embodiment of the present invention wherein the means of attaching the internal end 10 of a lip and/or nose bandage is reliant upon a mucosal adhesive applied to all or some part of that area 27 of the bottom surface 20 of the base sheet 18 demonstrated by the shaded section on the internal end 10 of the base sheet 18 . That area 29 of the dressing 14 distinguished from the rest of the dressing 14 by a dotted line may be cut away (as part of the manufacturing process) so as to match the area of application of mucosal adhesive on the bottom surface 20 of the base sheet 18 . In a preferred embodiment, a biocompatible adhesive for use in an oral environment, such as is described in U.S. Pat. No. 9,012,530 can be used. A biocompatible adhesive, such as the high-tack adhesive Wacker Silpuran 2117, can be applied to all or some part of that area 26 of the bottom surface 20 of the base sheet 18 demonstrated by the shaded section on the external end 8 of the base sheet 18 . That area 28 of the dressing 14 distinguished from the rest of the dressing by a dotted line may be cut away (as part of the manufacturing process) so as to match the area of application of skin adhesive on the bottom surface 20 of the base sheet 18 .
[0034] FIG. 7 shows a third embodiment of the present invention wherein the features illustrated in the first and second embodiments of the present invention are combined, that is, as means to affix the internal end 10 of the lip and/or nose bandage.
CITATION LIST
Patent Literature
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U.S. Pat. No. 1,111,679
U.S. Pat. No. 1,967,923
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U.S. Pat. No. 9,012,530 B2
Non Patent Literature
[0000]
US 2006/0206047 A1
US 2014/0350526 A1
US 2015/0018743 A1
US 2015/0088085 A1
http://www.ashasexualhealt.org/stdsstis/herpes/fast-facts-and-faqs
http://www.ascouncil.org/blogpost/1268738/218868/Wacker-Launches-High-Tack-Silicone-Adhesive-for-Medical-Applications
http://www.g3enterprises.com/closures/capsules.asp
http://www.corksupply.com/products/products-detail.aspx?pid=42&catid=31&returnurl=/products/capsules.aspx | The invention is directed to a bandage, particularly a lip and/or nose bandage for use on wounds (surgical or traumatic), scratches, sores, cold sores, blisters, fever blisters, ulcers, pimples, lesions, and burns. The lip and/or nose bandage comprises a base sheet layer (on one end associated with at least one skin adhesive); a dressing layer; and either or both of: (the same base sheet layer) on the other end associated with at least one mucosal adhesive; and/or a malleable layer positioned between the base sheet and dressing layers. | 0 |
FIELD OF THE INVENTION
The present invention relates to an amplifying device having a plurality units of amplifying means as well as to a transmission output control apparatus, and more particularly to a transmission output control apparatus used for a mobile information communication terminal or the like.
BACKGROUND OF THE INVENTION
FIG. 5 is a block diagram showing a transmission output control apparatus having a conventional type of amplifying device.
In FIG. 5, the reference numeral 1 indicates an input terminal to which a transmitter signal to the transmission output control apparatus is inputted, and the reference numeral 2 indicates an amplifier circuit in an exciting stage for amplifying the signal inputted into this input terminal 1. The reference numeral 3 is an amplifier circuit in a final stage for receiving a signal outputted from the amplifier circuit 2 in the exciting stage and amplifying power of the signal, said amplifier circuit comprising a FET (field effect transistor). The reference numeral 4 is an output terminal for taking out transmission output with the power amplified in an amplifier circuit 3 in the final stage.
The reference numeral 5 indicates a power supply terminal for supplying a drain voltage to the FET in the amplifier circuit 3 in the final stage, and the reference numeral 6 indicates a drain voltage switching means for switching a drain voltage supplied from the power supply terminal 5 to the FET in the amplifier circuit 3 in the final stage.
The reference numeral 7 is a coupler for taking out output from the amplifier circuit 3 in the final stage branching a portion thereof, and the reference numeral 8 indicates a detector circuit for detecting a signal taken out in the coupler 7 and outputting a signal corresponding to an output power from the amplifier circuit 3 in the final stage. The reference numeral 9 is a control means for generating a signal for specifying output power from the amplifier circuit 3 in the final stage, and this control means also controls the drain voltage switching means 6.
The reference numeral 10 is a power control circuit for generating a control signal for controlling output from the amplifier circuit 2 in the exciting stage according to a signal outputted from the detector circuit 8 as well as to the output power select signal generated in the control means 9. The reference numeral 11 is a power control transistor for controlling output from the amplifier circuit 2 in the exciting stage according to a control signal from the power control circuit 10.
Next description is made of the operation of the circuit.
At first, a control signal for controlling the drain voltage switching means 6 is outputted from the control means 9. When this control signal is at a low level, a switching transistor in the drain voltage switching means 6 is energized. In this case, the drain voltage from the power supply terminal 5 is supplied to a drain terminal of the FET in the amplifier circuit 3 in the final stage. With this, operation of the amplifier circuit 3 in the final stage is started, and power of an input signal from the input terminal 1 amplified in the amplifier circuit 2 in the exciting stage is amplified with the signal outputted from the outputted terminal 4 through the coupler 7.
On the other hand, a portion of the output from the amplifier circuit 3 in the final stage is branched by the coupler 7 and is inputted into the detector circuit 8. The detector circuit 8 detects a portion of the output from the amplifier circuit 3 in the final stage branched by the coupler 7 and generates a signal corresponding to output power from the amplifier circuit 3 in the final stage. The power control circuit 10 compares an output power select signal generated by the control means 9 to the signal corresponding to output power from the amplifier circuit 3 in the final stage which is generated in the detector circuit 8, generates a control signal so that the output power from the amplifier circuit 3 in the final stage is equalized to the power selected according to the output power select signal generated in the control means 9, and sends the signal to the power control transistor 11.
The power control transistor 11 controls a voltage loaded to the amplifier circuit 2 in the exciting stage according to a control signal generated in the power control circuit 10 and provides controls so that the output power from the amplifier circuit in the final stage is equalized to and maintained at the same level as the power selected according to the output power select signal generated in the control means 9.
Configuration of an amplifier apparatus based on the conventional technology is as described above, so that a voltage is always loaded to a drain terminal of the FET in the amplifier circuit 3 in the final stage. Generally, in a case where a drain voltage is loaded to an amplifying means such as an FET or an NPN transistor, isolation between the gate and drain becomes poorer, and sometimes power inputted to the gate terminal may be leaked to the drain terminal. For this reason, in a case where low output power is required such as when it is required that output power from an amplifying device is smaller than input power thereto, even if a voltage loaded to the amplifier 2 in the exciting stage is controlled, the power inputted into the gate terminal is leaked to the drain terminal and is added to the output power therefrom because of the characteristics of the amplifying means as described above. For this reason, even if lower output power is required, sometimes it may be impossible to suppress the output power to a certain level or below.
SUMMARY OF THE INVENTION
It is an object of the present invention to obtain an amplifying device and a transmission output power control unit which can control output power in a wide range.
The amplifying device according to the first feature of the present invention comprises the first amplifying means for amplifying an inputted signal and outputting the amplified signal, the second amplifying means for amplifying an inputted signal and outputting the amplified signal, the power supply unit for supplying power to the first amplifying means and to the second amplifying means, the switching means for controlling power supply from the power supply unit to the first amplifying means as well as to the second amplifying means according to a control signal, and the control means for outputting a control signal for controlling the switching means, to the switching means, so that power is supplied to the first amplifying means with power supply to the second amplifying means suppressed in low amplification and also power is supplied to both the first and second amplifying means in high amplification, and for this reason, especially when lower output power is required, the output power can be suppressed to a certain level or below and can also be controlled in a wide range.
In the amplifying device according to the second feature of the present invention, the control means further generates a power select signal for specifying power of an output signal from the amplifying device, the switching means further controls power supply to the first amplifying means according to a power control signal, and the amplifying device further comprises the detecting means for detecting a signal corresponding to power of an output signal from the amplifying device and a power control means for generating a power control signal for controlling power of an output signal from the amplifying device according to a signal detected by the detecting means as well as to the power select signal and outputting the power select signal to the switching means, so that the output power can further be stabilized in addition to the effect achieved in the first feature of the present invention.
In the amplifying device according to the third feature of the present invention, the control means outputs, when output from the amplifying device is to be suppressed, a power control signal for suppressing the output to the power control means, so that it is not required to further discretely provide therein a switching means for suppressing power from the power supply unit to the first amplifying means, which makes it possible to reduce a circuit scale.
In the amplifying device according to the fourth feature of the present invention, the switching means comprises the first switching means for controlling power supply to the first amplifying means according to the power control signal outputted from the power control means and the second switching means for controlling power supply from the power supply unit to the second amplifying means, so that the output power can further be stabilized like in the effect obtained in the second feature of the present invention.
In the amplifying device according to the fifth feature of the present invention, the switching means comprises the second switching means for controlling power supply from the power supply unit to the second amplifying means and the third switching means for controlling power supply from the power supply unit to the first amplifying means as well as to the second amplifying means, so that, like the effect obtained in the first feature, especially when lower output power is required, the output power can be suppressed to a certain level or below and can also be controlled in a wide range.
In the amplifying device according to the sixth feature of the present invention, the control means outputs a control signal for controlling power to the second amplifying means to an arbitrary value, so that output power can be controlled with higher precision.
In the amplifying device according to the seventh feature of the present invention, the second amplifying means comprises a field effect transistor, so that it is possible to prevent such phenomenon as that power inputted especially to the gate terminal is leaked to the drain terminal.
In the amplifying device according to the eighth feature of the present invention, an input signal to the amplifying device is inputted into the first amplifying means, and a signal outputted from the first amplifying means is inputted into the second amplifying means, so that it is possible to prevent increase of output power in the amplifying means in the final stage.
The transmission output control apparatus according to the ninth feature of the present invention comprises the amplifying device, and an input signal to the amplifying device is a transmission signal, so that, especially when lower output power is required, the output power can be suppressed to a certain level or below and can also be controlled in a wide range.
Other objects and features of this invention will become understood from the following description with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing configuration of a transmission output control apparatus according to Embodiment 1 of the present invention;
FIG. 2 is a view showing transmission output power from a mobile information communication terminal according to Embodiment 2 of the present invention;
FIG. 3 is an example of information obtained by actually measuring output power from the transmission output control apparatus according to Embodiment 2 of the present invention;
FIG. 4 is a block diagram showing a transmission output control apparatus according to Embodiment 3 of the present invention; and
FIG. 5 is a block diagram showing a transmission output control apparatus based on the conventional technology.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Description is made hereinafter for Embodiment 1 of the present invention with reference to the related drawings. In Embodiment 1, description is made especially for a case where the amplifying device according to the present invention is applied to a transmission output control apparatus.
In FIG. 1, designated at the reference numeral 1 is an input terminal, at 2 an amplifier circuit in an exciting stage, at 3 an amplifier circuit in a final stage comprising a FET, at 4 an output terminal, at 5 a power supply terminal, at 6 a drain voltage switching means, at 7 a coupler, at 8 a detector circuit, at 10 a power control circuit, and at 11 a power control transistor, and the same reference numerals are assigned to the same sections corresponding to those in the conventional type of amplifying device.
The reference numeral 12 indicates a second drain voltage switching means for switching a drain voltage loaded to the amplifier 3 in the final stage from the power supply terminal 5 through the drain voltage switching means 6. The reference numeral 13 indicates a control means corresponding to the conventional type of control means 9 and the control means 13 also generates a control signal for the second drain voltage switching means 12 in addition to the output power select signal as the first control signal and a control signal of the drain voltage switching means as the second control.
Herein, in Embodiment 1, the amplifier circuit 2 in the exciting stage corresponds to a first amplifying means according to the present invention, the amplifier circuit 3 in the final stage to a second amplifying means according to the present invention, and the drain voltage switching means 6 as well as the second drain switching means 12 to a switching means according to the present invention. Also, the coupler 7 and detector circuit 8 correspond to a detecting means according to the present invention.
Next description is made of the operation of the circuit.
A transmitter signal inputted from the input terminal is basically outputted to the amplifier 3 in the final stage after the signal is inputted to the amplifier 2 in the exciting stage and is amplified. The amplifier 3 in the final stage amplifies the signal received from the amplifier 2 in the exciting stage and outputs the amplified signal to the output terminal 4.
Next description is made for a case where the transmission output power of a transmitter signal outputted from the output terminal 4 is to be suppressed to a low level.
In this case, a control signal outputted from the control means 13 for controlling the drain voltage switching means 6 is set to a low level, while a control signal for controlling the second drain voltage switching means 12 is set to a high level. With these control signals, the drain voltage switching means 6 is energized, while the second drain voltage switching means 12 is electrically disconnected. With this feature, a voltage is not supplied to a drain terminal of the FET in the amplifier 3 in the final stage, but a voltage is supplied from the power supply terminal 5 only to the amplifier 2 in the exciting stage through the power control transistor 11.
The transmitter signal inputted from the input terminal 1 is inputted to the amplifier 3 in the final stage amplified by the amplifier 2 in the exciting stage. Herein, a voltage is not loaded to the drain terminal of the FET in the amplifier 3 in the final stage, so that the drain terminal is opened and the inputted transmitter signal is attenuated due to junction resistance of the FET between the gate and the drain, and the attenuated signal is outputted.
An output signal outputted from the amplifier 3 in the final stage is outputted from the output terminal 4 through the coupler 7. A portion of the output from the amplifier 3 in the final stage is branched by the coupler 7 and inputted into the detector circuit 8. The detector circuit 8 detects a portion of the output from the amplifier 3 in the final stage branched by the coupler 7, and generates a signal corresponding to output power from the amplifier 3 in the final stage. The power control circuit 10 compares an output power select signal generated by the control means 13 to a signal corresponding to output power from the amplifier 3 in the final stage generated in the detector circuit 8, generates a control signal so that the output power from the amplifier 3 in the final stage is equalized to the same level as the power selected according to the output power select signal generated in the control means 13, and sends the signal to the power control transistor 11. The power control transistor 11 controls a voltage loaded to the amplifier 2 in the exciting stage according to the control signal generated by the power control circuit 10 so that the output power from the amplifier 3 in the final stage is equalized to and maintained at the same level as the power selected according to the output power select signal generated in the control means 13.
Next description is made for a case where transmission output power is set to a higher level.
In this case, both a control signal for controlling the drain voltage switching means 6 and a control signal for controlling the second drain voltage switching means 12 each outputted from the control means 13 are set to a low level. In this operation, both the drain voltage switching means 6 and second drain voltage switching means 12 are energized, and a transmitter signal inputted from the input terminal 1 is amplified by the amplifier 2 in the exciting stage and further is amplified by the amplifier 3 in the final stage to be outputted from the output terminal through the coupler 7.
It should be noted that the apparatus according to Embodiment 1 has the configuration in which power to the amplifier 2 in the exciting stage is controlled by the power control circuit 10 and that to the amplifier 3 in the final stage is controlled by the control means 13, but conversely the apparatus according to Embodiment 1 may have the configuration in which power to the amplifier 3 in the final stage is controlled by the power control circuit 10 and that to the amplifier 2 in the exciting stage is controlled by the control means 13.
As described above, the amplifying device according to Embodiment 1 of the present invention comprises a first amplifying means for amplifying an inputted signal and outputting the amplified signal, a second amplifying means for amplifying an inputted signal and outputting the amplified signal, a power supply unit for supplying power to the first amplifying means and to the second amplifying means, a switching means for controlling the power supplied from the power supply unit to the first amplifying means as well as to the second amplifying means according to a control signal, and a control means for outputting a control signal for controlling the switching means, to the switching means, so that power is supplied to the first amplifying means with the power supply to the second amplifying means suppressed in low amplification and also power is supplied to both the first and second amplifying means in high amplification, and for this reason, especially when low output power is required, the output power can be suppressed to a certain level or below and can be controlled in a wide range.
Furthermore, the control means further generates a power select signal for specifying power of an output signal from the amplifying device, the switching means further controls power supply to the first amplifying means according to a power control signal, and the amplifying device further comprises a detecting means for detecting a signal corresponding to power of an output signal from the amplifying device and a power control means for generating a power control signal for controlling power of an output signal from the amplifying device according to a signal detected by the detecting means as well as to the power select signal and outputting the power control signal to the switching means, so that the output power can further be stabilized.
In Embodiment 2, description is made for a case where the amplifying device and the transmission output control apparatus according to the present invention are applied to a mobile information communication terminal specified in North American mobile information communication system--Cellular Digital Packet Data Release 1.1 (described as CDPD hereinafter).
FIG. 2 is a view showing transmission output power of the mobile information communication terminal specified in the CDPD. In the CDPD as shown in the figure, types of the mobile information communication terminal are classified into Classes 1 to 4 according to a level of the transmission output power.
FIG. 3 is a view showing an example of information obtained by actually measuring output power from the amplifier 3 in the final stage to a power voltage (a voltage of the collector in the power control transistor 11) of the amplifier 2 in the exciting stage in the transmission output control apparatus to which one of Embodiments of the present invention is applied.
Description is made for a case where the transmission output control apparatus with the characteristics as shown in FIG. 3 is applied to the specification of Class 4 shown in FIG. 2. For instance, when a signal is to be transmitted with output power at LEVEL 0, a signal for controlling the second drain voltage switching means 12 outputted from the control means 13 is set to a low level, and a voltage is loaded to the drain terminal of the FET in the amplifier 3 in the final stage, whereby the amplifier 3 in the final stage is operated. And at the same time, if an output power select signal generated by the control means 13 is selected so that a collector voltage of the power control transistor 11 is 1.5 V, output power of -2 dBW can be obtained.
Then, when a signal is to be transmitted in output power of LEVEL 8, a signal for controlling the second drain voltage switching means 12 outputted from the control means 13 is set to a high level so that a voltage is not supplied to the drain terminal of the FET in the amplifier 3 in the final stage. If an output power select signal generated by the control means 13 is selected so that a collector voltage of the power control transistor 11 is 1.3 V, output power of -26 dBW can be obtained. Similarly, if a voltage is supplied to the drain terminal of the FET in the amplifier 3 in the final stage in a range from LEVELS 1 to 7 and a voltage is not supplied to the drain terminal of the FET in the amplifier 3 in the final stage in a range from LEVELS 9 to 10, output power at all the levels can be obtained by appropriately selecting output power select signal generated by the control means 13.
As described above, a transmission output control apparatus with which output power can be controlled in a wide range can be obtained by providing the second drain voltage switching means 12 and controlling it by the control means 13.
FIG. 4 shows a transmission output control apparatus having an amplifying device according to Embodiment 3 of the present invention. In Embodiment 3, especially the drain voltage switching means 6 and the second drain voltage switching means 12 each according to Embodiment 1 are integrated into one unit.
In the figure, the reference numeral 14 indicates a drain voltage switching means in which the drain voltage switching means 6 and the second drain voltage switching means 12 each according to Embodiment 1 are integrated, and the reference numeral 15 indicates a control means corresponding to the control means 13 according to Embodiment 1 and the control means generates a control signal for the drain voltage switching means 14 in addition to an output power select signal which is the first control signal.
Description is made hereinafter for the related drawings.
When transmission output power is set to a high level, if a signal outputted from the control means 15 for controlling the drain voltage switching means 14 is to be set to a low level, the drain voltage switching means 14 is energized, and a transmitter signal inputted from the input terminal 1 is amplified by the amplifier 2 in the exciting stage and is amplified by the amplifier 3 in the final stage to be outputted from the output terminal through the coupler 7. When transmission output power thereof is set to a low level, if a signal outputted from the control means 15 for controlling the drain voltage switching means 14 is set to a higher level, the drain voltage switching means 14 is not energized, so that a transmitter signal inputted from the input terminal 1 is amplified by the amplifier 2 in the exciting stage, and is attenuated by the amplifier 3 in the final stage to be outputted from the output terminal through the coupler 7.
When transmission output is to be turned OFF, a transmission output select signal outputted from the control means 15 is sent so that a signal of a base terminal in the power control transistor 11 outputted from the power control circuit 10 is set to a high level, and if a signal for controlling the drain voltage switching means 14 is set to a high level, a voltage is not loaded to the amplifier 2 in the exciting stage as well as to the amplifier 3 in the final stage, so that the transmission output can be turned OFF.
In the amplifying device according to Embodiment 3, especially, the control means outputs, when output from the amplifying device is to be suppressed, a power control signal for suppressing the output to the power control means, so that it is not required to further discretely provide therein a switching means for suppressing power from the power supply unit to the first amplifying means, which makes it possible to reduce a circuit scale.
Although each of Embodiments 1 to 3 has the configuration in which the drain voltage switching means 14 is turned ON or OFF according to a signal from the control means 15, by setting the signal from the control means 15 to an appropriate value, a voltage loaded to the drain terminal of the FET in the amplifier 3 in the final stage can be controlled to an appropriate value, and any arbitrary amplification factor of the amplifier 3 in the final stage can be selected. By selecting any arbitrary amplification factor of the amplifier 3 in the final stage, output power can be controlled with higher precision.
In each of Embodiments as described above, an FET is used as an amplifying means, but an amplifying means according to the present invention is not restricted to the FET, and any amplifier such as an NPN transistor or the like is allowable so long as it has such characteristics that isolation between the gate and drain becomes poorer when a drain voltage is loaded thereto.
This application is based on Japanese patent application No. HEI 9-16846 filed in the Japanese Patent Office on Jan. 30, 1997, the entire contents of which are hereby incorporated by reference.
Although the invention has been described with respect to a specific embodiment for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art which fairly fall within the basic teaching herein set forth. | A second drain voltage switch is provided to turn ON/OFF a drain voltage in an amplifier in the final stage, the drain voltage in the amplifier in the final stage is turned ON when large output power is required, and the drain voltage in the amplifier in the final stage is turned OFF when small output power is required, thus a transmission output control apparatus capable of controlling output power in a wide range being obtained. | 7 |
BACKGROUND OF THE INVENTION 1. Field of the Invention
This invention relates to an electric circuit containing an integral phase-locked loop, and, more particularly, to an improvement thereof whereby the phase-locked loop may be selectively disabled to permit operation of the circuit in a mode in which the loop is not required.
2. Description of the Prior Art
Recently, the advantageous features of the phase-locked loop (hereinafter abbreviated to PLL) have been widely utilized, for instance, in the fields of FM detecting circuits, FM stereophonic multiplex circuits, and AM detecting circuits, and integrated circuits for these applications are readily available on the market. The PLL inherently comprises a phase difference detector, a d.c. amplifier, and a voltage-controlled oscillator which is continuously operated even in an operational mode of the circuit where the PLL is not utilized. The drawback of such an arrangement is that the output oscillation signal from the voltage-controlled oscillator, including higher harmonics, interferes, with other devices, such as audio circuits. In view of this drawback, it would be advantageous to put the PLL in an inoperative state in the cases where the PLL is utilized in a circuit wherein two series of amplifiers are employed, as in the cases of simply reproducing recorded discs or recorded tapes. Of course, it is possible to put the PLL into an inoperative state by merely turning the power source to an OFF state. However, ON-OFF operations of the power source cause transient phenomena in the circuit which in turn give rise to the creation of noise in the sound from the loudspeakers.
SUMMARY OF THE INVENTION
The present invention is directed to the elimination of the above described drawback of the conventional construction, and a primary object is to provide an improved arrangement wherein the oscillation in the voltage-controlled oscillator constituting a principal constituent of the PLL circuit is terminated in an operational mode not utilizing the PLL circuit, and any hazardous influence of the higher harmonics thereof is thereby eliminated.
The present invention will now be described in detail with reference to the accompanying drawing which illustrates a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram showing an embodiment of the present invention, and FIGS. 2 and 3 are circuit diagrams showing examples of voltage-controlled oscillator included in the PLL circuit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, there is illustrateed a block diagram of a so-called two-channel stereo receiver which includes an FM stereo multiplex circuit and an AM detecting circuit. Each of the circuits includes a PLL. In the drawwing, numeral 1 designates an FM detector delivering a composite signal within which a pilot signal of 19 KHz is thereafter sent through a PLL comprising a phase difference detector 2, a d.c. amplifier 3, a voltage-controlled oscillator 4, and a frequency divider 5 such as a flip-flop or the like, thereby locking the PLL at 19 KHz of the pilot signal. The voltage-controlled oscillator 4 is oscillated while it is locked to 38 KHz, i.e., twice the frequency of the 19 KHz pilot signal, and the output thereof is applied to a switching circuit 6 thereby to operate the switching circuit to demodulate the output signal from the FM detector 1 into two channels of FM stereophonic output signals. The two channels of FM stereophonic output signals are then led to terminals S 1-2 and S 1-3 in two switch portions SW 2 and SW 3 within three-stage ganged switches SW 1 through SW 3 , through which the two channels of the output signals are applied to amplifiers 7 and 8 so that output stereophonic signals are obtained from the output terminals 9 and 10 of the amplifiers 7 and 8. During this mode of operation, a d.c. positive voltage from a signal source 11 is interrupted by the switch SW 1 from being connected via switch terminal S 1-1 to the voltage-controlled oscillator 4, and the oscillator 4 is thereby operated in normal manner.
On the other hand, a modulated input signal, which is obtained through AM modulation of a carrier wave by a voice signal, is applied to a second PLL comprising a phase difference detector 12, a d.c. amplifier 13, and a voltage-controlled oscillator 14, thereby locking this PLL to the frequency of the carrier wave. Simultaneous therewith, the above-mentioned input signal and the output signal from the voltage-contolled oscillator 14 are both applied to a multiplier 15 thereby obtaining an AM demodulated signal. In the operational mode shown in FIG. 1, the entire circuit is operated in an FM multidemodulation mode, during which the second PLL is maintained in an inoperative state by applying the positive voltage from signal source 11 to the voltage-controlled oscillator 14 through the switch SW 1 and terminal S 2-1 .
When the ganged switches SW 1 through SW 3 are transferred to "AUX" position, only an input signal applied to the "AUX" terminals is applied via the switch terminals S 3-2 and S 3-3 to the amplifiers 7 and 8, and both of the voltage-controlled oscillators 4 and 14 are made inoperative through the application of the d.c. positive voltage to the oscillators 4 and 14 via switch terminals S 1-1 and S 2-1 respectively.
In FIG. 2, there is indicated an example wherein the voltage-controlled oscillator (VCO) constituting a component of the PLL circuit is made in the form of a Schmitt trigger circuit. The part surrounded by a broken line in the drawing is formed into various integrated circuits of which NE565 and NE566 are typical.
A control voltage from the d.c. amplifier 3 is applied to a constant current source 21, thereby limiting the amount of current flowing into the control circuit comprising diodes D 1 and D 2 and transistors Q 1 and Q 2 . The Schmitt trigger circuit 22 is connected to the collector of the transistor Q 2 , and a capacitor C 1 for determining the oscillation frequency is connected in parallel with the Schmitt trigger circuit 22. Furthermore, an NPN transistor Q 3 is connected in parallel with the capacitor C 1 and with the input terminal of the Schmitt trigger circuit 22. Thus, when a control signal in the form of a d.c. voltage higher than +0.7 V is applied to the base of the transistor Q 3 , the transistor conducts, and the voltage applied across the capacitor C 1 is thus lowered. The resulting lowering or grounding of the input voltage of the Schmitt trigger circuit 22 terminates the operation thereof.
Describing the operation of the VCO shown in FIG. 2 in relation to the circuit shown in FIG. 1, this VCO may be incorporated in the FM multiplex circuit as VCO 4. In this case, the base of the transistor Q 3 is connected with the terminal S 1-1 in the switch SW 1 . The exemplary VCO of FIG. 2 may also be incorporateed in the AM detector circuit in FIG. 1 as VCO 14, and in this case, the base of the transistor Q 3 is connected with the terminal S 2-1 of the switch SW 1 .
In FIG. 3, there is illustrated another form of a voltage-controlled oscillator utilizing a multivibrator. The part surrounded by the broken line in FIG. 3 is formed into various integrated circuits of which NE561 and NE562 are typical. Since these integrated circuits per se are not part of the present invention, detailed description of their operation will be omitted.
In brief, a control voltage from d.c. amplifier 3 in FIG. 1 is applied to a terminal 31 of the circuit surrounded by the broken line, whereby the transistors Q 5 and Q 6 are caused to repeat ON-OFF operation alternately at a frequency depending on the magnitude of input control votlage. In the example shown in FIG. 3, another PNP transistor Q 7 is provided between the collector and emitter of the transistor Q 6 , and the oscillation of the multivibrator is terminated by applying a control signal to the base of the transistor Q 7 , rendering transistor Q 7 conductive and short-circuiting transistor Q 6 . It will be clearly understood that in this example, the multivibrator is operated when +B voltage is applied to the base of the transistor Q 7 , and the operation of the multivibrator is terminated when a voltage lower than 0.7 V is applied to the base of the same transistor.
Accordingly, the relation between the operation of the oscillator and the applied control voltage is just reverse of that of the Schmitt trigger type oscillator shown in FIG. 2. For this reason, the contact arrangement in the switch SW 1 in FIG. 1 cannot be used for the example shown in FIG. 3, and hence a minor change must be made for this part of the circuit.
Among voltage controlled oscillators, there are MC131OP and μA758 besides the above described types, and in these types, oscillation can be terminated by simply grounding the input terminal. Thus, when an operational mode requiring no PLL circuit is selected, the object of the invention can be achieved by so composing the circuit that the input terminal thereof is grounded through a ganged switch or a switching element, such as a transistor.
Since the invention is organized as described above, the transient phenomenon caused by ON-OFF control of the power source for PLL circuit can be eliminated. Furthermore, when the electric apparatus is operated in a mode not requiring the PLL, the voltage-controlled oscillator thereof can be sureby brought into inoperative state, and the interference of higher harmonics to other apparatuses can be thereby prevented. In addition, the operation of the voltage-controlled oscillator can be terminated without varying the oscillator portion thereof, whereby any possibility of deteriorating the stability in operation of the voltage-controlled oscillator due to circumferential conditions and other factors can be substantially eliminated.
Although the preferred embodiment of the invention has been described with respect to a so-called two-channel stereo receiver circuit, the invention is not restricted to such a specific circuit, but rather is applicable to various other circuits and apparatuses containing a PLL and utilizing the PLL upon requirement; therefore, various modifications and alterations can be effectuated without departing from the scope and spirit of the present invention as defined in the appended claims. | A circuit containing an integral phase-locked loop and operative in a first mode, in which the loop is required, and in a second mode in which the loop is not required; and means for selectively rendering the loop inoperative by selectively disabling the voltage-controlled oscillator thereof. | 7 |
FIELD OF THE INVENTION
The present invention relates to new derivatives of 1-ethyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid and 1-ethyl-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid, both substituted in position 7 by the 1-pyrrolyl group, and also to their preparation and application as drugs.
SUMMARY OF THE INVENTION
The new derivatives which are the subject of the present invention correspond to the general formula I: ##STR2## in which: X represents a carbon atom or a nitrogen atom, and
R represents a hydrogen atom or a fluorine atom.
The present invention also relates to the physiologically acceptable alkali metal salts or alkaline earth metal salts of the compounds of general formula I.
The derivatives of general formua I and their salts have useful antimicrobial pharmacological properties, notably antibacterial and fungistatic properties.
The new compounds have powerful antibacterial activity in respect of both gram positive and gram negative bacteria.
DETAILED DESCRIPTION
The new derivatives of general formula I can be prepared according to the invention by means of the following reaction scheme: ##STR3## where X and R have the meanings given above.
In stage A, the appropriate diamine is condensed directly with diethyl ethoxymethylenemalonate to give the ethyl monoaminomethylenemalonate by elimination of alcohol. During stage B, the compound is cyclized by heating either in the absence of solvent, or employing an appropriate solvent which acts as a thermal exchanger such as, for example, benzene, toluene, xylene, tetralin, nitrobenzene, dichlorobenzene, diphenyl ether or biphenyl, or, furthermore, a mixture of these solvents.
The reaction temperature is between 150° C. and 250° C., preferably between 180°-230° C. By using certain catalysts, it is possible to effect the cyclization at much lower temperatures. Among the appropriate catalysts, polyphosphoric ester, polyphosphoric acid, phosphoric anhydride, etc., may be mentioned by way of example. With these catalysts, temperatures generally between 60°-170° C. are employed, or better still, between 75° C. and 150° C.
During stage C, the N-alkylated compounds are then prepared. The alkylation can be performed using one of the conventional alkylating agents, which include, among others, the alkyl halides, the dialkyl sulfates, the alkyl sulfonates, etc.
In general, the reaction is performed in the presence of an alkali and in a solvent which is inert with respect to the reaction. The solvents, can, in particular, consist of water, methanol, ethanol, acetone, dioxane, benzene, dimethylformamide, dimethylsulfoxide, as well as mixtures of these solvents.
The preferred alkalis which can be used are the alkali metal hydroxides, such as sodium hydroxide and potassium hydroxide, or else alkali metal carbonates, such as sodium carbonate or potassium carbonate.
It should be noted that during stage C, the alkylation process is accompanied by a hydrolysis of the carboxylic ester since the medium is distinctly alkaline, so that the corresponding carboxylic acids are obtained.
In the final stage D, the pyrrole nucleus is grafted according to the method of Clauson-Kaas, Acta Chem. Scand. 6, 667 and 867 (1952), by reaction of the amine with dimethoxytetrahydrofuran by refluxing for a half hour in acetic acid medium.
In the particular case of the preparation of 1-ethyl-1,4-dihydro-4-oxo-6-fluoro-7-(1-pyrrolyl)-1,8-naphthyridine-3-carboxylic acid, it should be noted that the synthesis intermediate necessary for performing the grafting of the pyrrole nucleus in stage D is new, and, by virtue of this, also forms a part of the present invention.
In this particular case, this reaction stage D is schematized as follows: ##STR4##
This synthesis intermediate can be prepared for example from 1-ethyl-1,4-dihydro-4-oxo-6-fluoro-7-chloro-1,8-naphthyridine-3-carboxylic acid (for example, described in European Patent Application No. 0,027,752) according to the following reaction scheme: ##STR5##
In the following examples, the preparation of new derivatives according to the invention will be indicated, as well as corresponding starting materials and intermediate products. Some typical forms of using the compounds will also be described, for the different fields of application.
The examples below, which are given simply by way of illustration, must not, however, be taken to limit in any way the scope of the invention.
EXAMPLE 1
Preparation of diethyl 3-aminoanilino-methylenemalonate (stage A)
10.8 Grams of m-phenylenediamine are dissolved in 80 ml of ethyl alcohol, 21.6 grams of diethyl ethoxymethylenemalonate are added and the mixture is heated under reflux for 40 minutes. After filtration hot, 50 ml of water are added and the mixture is left for 24 to 36 hours at room temperature with stirring. The precipitate formed is filtered off, washed with an ethanol/water (1:1) mixture and dried at 60° C. The product is recrystallized in a benzene/hexane (2:1) mixture and 10.5 grams of a solid are obtained, of melting point 71°-74° C.
Preparation of ethyl 7-acetamido-4-hydroxy-3-quinolinecarboxylate (stage B)
10.5 Grams of diethyl 3-aminoanilino-methylenemalonate are dissolved in 80 ml of diphenyl oxide, 8 ml of acetic anhydride are added and the mixture is gradually heated to 250° C. and maintained under reflux for 10 minutes. The mixture is allowed to cool, 20 ml of ethanol are added and the solid is filtered off and washed with ethanol. The product is recrystallized in dimethylformamide and 4.6 grams of a solid are obtained, of melting point 295° to 300° C.
Preparation of 7-amino-1-ethyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid (stage C)
4.6 Grams of ethyl 7-acetamido-4-hydroxy-3-quinolinecarboxylate are dissolved in 15 ml of 10% NaOH, 60 ml of H 2 O and 100 ml of ethanol, and 5 ml of ethyl bromide are added. The mixture is left under reflux for 4 hours, then the excess of ethyl bromide and ethanol is evaporated off, and 10 ml of 10% NaOH are then added. The mixture is heated under reflux for 2 hours, allowed to cool, acidified with HCl, filtered and treated with ethanol at 70° C. The product is filtered off and recrystallized in a dimethylformamide/water (1:1) mixture. 1.0 Gram of a solid is obtained, of melting point 304°-307° C.
Preparation of 7-(1-pyrrolyl)-1-ethyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid (stage D)
0.3 Gram of 7-amino-1-ethyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid is suspended in 10 ml of acetic acid, 0.17 gram of dimethoxytetrahydrofuran is added and the mixture is heated until the solid has dissolved. The mixture is filtered, and water is added to the filtrate until it becomes turbid. The filtrate is allowed to cool, and the precipitate obtained is filtered off and washed with ethanol. 0.12 gram of a solid is obtained, of melting point 235°-238° C.
Spectroscopic data:
1 H NMR,δ,[DMSO (d 6 )]: 1.46 (t,3H); 4.57 (q, 2H); 6.23 (m, 2H); 7.43 (m, 2H); 7.59 [d(J=8 Hz), 1H]; 7.68 (s, 1H); 8.18 [d(J=8 Hz), 1H]; 8.76 (s, 1H); 14.80 (s, 1H).
IR (KBr): 1620, 1720 cm -1 .
EXAMPLE 2
Preparation of 4-fluoro-m-phenylenediamine
To a solution of 9 grams of SnCl 2 .2H 2 O in 12 ml of concentrated HCl, are added in a single batch, with stirring, 1.6 grams of 4-fluoro-3-nitroaniline, which dissolves as a brisk reaction occurs, the temperature reaching 95° to 100° C. The reaction mixture is allowed to cool to room temperature, and poured into 70 ml of 50% NaOH solution in ice, so that the temperature remains below 20° C. The resultant strongly alkaline solution is extracted 3 times with 50 ml of ethyl ether. The ethyl ether extracts are combined, washed with 30 ml of distilled water and dried with anhydrous sodium sulfate. The ethyl ether solution is evaporated to dryness and 1.2 gram of a dark colored oil is obtained.
Preparation of diethyl 4-fluoro-3-aminoanilinomethylenemalonate (stage A)
A solution of 2.16 grams of diethyl ethoxymethylenemalonate and 1.26 gram of 4-fluoro-m-phenylenediamine in 40 ml of ethanol is heated under reflux for 30 minutes, and 15 ml of water are added while the mixture is hot. The mixture is allowed to cool and the precipitate formed filtered off and washed with an ethanol/H 2 O (1:1) mixture. The product is dried at 60° C. and recrystallized in a benzene/hexane (2:1) mixture, giving 1.6 gram of crystals, of melting point 100°-102° C.
Preparation of ethyl 7-acetamido-4-hydroxy-6-fluoro-3-quinolinecarboxylate (stage B)
1.6 Gram of diethyl 4-fluoro-3-aminoanilinomethylenemalonate is dissolved in a mixture of 8 ml of diphenyl oxide and 1 ml of acetic anhydride, and the mixture is heated gradually to 250° C., at which temperature a precipitate appears. The mixture is left under reflux for 10 minutes and allowed to cool. 5 ml of ethanol are added and the solid is filtered off and washed with ethanol. The product is recrystallized in dimethylformamide and 1 gram of a solid is obtained, of melting point 320° C.
Preparation of 6-fluoro-7-amino-1-ethyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid (stage C)
1.5 ml of ethyl bromide is added to a solution of 1 gram of ethyl 7-acetamido-4-hydroxy-6-fluoro-3-quinolinecarboxylate in 25 ml of water, 60 ml of ethanol and 2.5 ml of 10% sodium hydroxide solution, and the mixture is maintained under reflux for 4 hours. The mixture is then concentrated to half its volume, 5 ml of 10% sodium hydroxide solution are added and refluxing is maintained for 1 hour. The mixture is allowed to cool and is acidified with hydrochloric acid, and the precipitate formed is filtered off. The precipitate is washed with water, dried, and recrystallized in a dimethylformamide/water (10:1) mixture.
0.65 Gram of a solid is obtained, which melts at 298°-300° C. with decomposition.
Preparation of 6-fluoro-7-(1-pyrrolyl)-1-ethyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid (stage D)
2.5 Grams of 6-fluoro-7-amino-1-ethyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid are suspended in 15 ml of acetic acid, and 1.32 gram of dimethoxytetrahydrofuran is added; the mixture is heated gradually until the solid dissolves, and is then allowed to cool. The precipitate formed is filtered off and washed with ethanol. The product is recrystallized in acetonitrile, and 1.4 gram of needles is obtained, of melting point 251°-252° C.
Spectroscopic data:
1 H NMR,δ, [DMSO (d 6 )]: 1.48 (t,3H); 4.62 (q,2H); 6.38 (t,2H); 7.34 (q,2H); 7.99 [d(J=6.1 Hz),1H]; 8.10 [d(J=11.4 Hz),1H]; 8.92 (s, 1H); 14.65 (s,1H).
IR (KBr): 1620, 1720 cm -1 .
EXAMPLE 3
Preparation of 1-ethyl-1,4-dihydro-4-oxo-7-(1-pyrrolyl)-1,8-naphthyridine-3-carboxylic acid (stage D)
4.6 Grams of 1-ethyl-1,4-dihydro-4-oxo-7-amino-1,8-naphthyridine-3-carboxylic acid (U.S. Pat. No. 3,149,104) and 2.7 grams of 2,5-dimethoxytetrahydrofuran are placed under reflux for 30 minutes in 70 ml of glacial acetic acid. The mixture is allowed to cool then left for 8 hours at 5° C., and a precipitate is obtained which, when filtered off and recrystallized in acetonitrile, gives 4.3 grams of needles, of melting point 230°-232° C.
Spectroscopic data:
1 H NMR, δ, [DMSO (d 6 )]: 1.47 (t,3H); 4.57 (q,2H); 6.30 (m,2H ); 7.70 (m,2H); 7.80 [d(J=8.4 Hz), 1H]; 8.53 [d(J=8.4 Hz), 1H]; 8.95 (s,1H); 14.62 (s, 1H).
IR (KBr): 1625, 1720 cm -1 .
EXAMPLE 4
Preparation of 1-ethyl-1,4-dihydro-4-oxo-6-fluoro-7-(1-pyrrolyl)-1,8-naphthyridine-3-carboxylic acid (stage D)
1.4 gram of 1-ethyl-1,4-dihydro-4-oxo-6-fluoro-7-amino-1,8-naphthyridine-3-carboxylic acid, having a melting point of 299°-303° C. (decomposes) and giving the following spectroscopic data:
1 H NMR,δ, [CF 3 COOH]: 1.70 (t,3H); 4.83 (q,2H); 8.10 [d(J=9.4 Hz),1H]; 9.11 (s,1H).
IR (KBr): 1650, 1720, 3320, 3425 cm -1 ,
is suspended in 20 ml of a mixture of acetic acid and dimethylformamide (1:1) 0.8 Gram of 2,5-dimethoxytetrahydrofuran is added, and the mixture is heated under reflux for 10 minutes. After being left to cool, the mixture is left standing for 8 hours at 5° C., and a precipitate is obtained which, when filtered off and recrystallized in acetone, gives 0.95 gram of needle-shaped crystals, of melting point 257°-259° C.
Spectroscopic data:
1 H NMR,δ, [CF 3 COOH]: 1.67 (t,3H); 4.88 (q,2H); 6.36 (m,2H); 7.68 (m,2H); 8.40 [d(J=11 Hz),1H]; 9.23 (s,1H).
IR (KBr): 1625, 1725 cm -1 .
The starting compound can be prepared as follows:
1 Gram of 1-ethyl-1,4-dihydro-4-oxo-6-fluoro-7-chloro-1,8-naphthyridine-3-carboxylic acid (for example, described in European Patent Application No. 0,027,752) is mixed with 25 ml of concentrated ammonia solution containing 20% of ethanol. The mixture is maintained in a sealed tube for 4 hours at 120°-125° C. The mixture is cooled, and acetic acid added until the pH is slightly acid, when the precipitate formed is filtered off and washed with water. The product is dried, 0.8 gram of 1-ethyl-1,4-dihydro-4-oxo-6-fluoro-7-amino-1,8-naphthyridine-3-carboxylic acid being obtained, of melting point 299°-303° C.
Antimicrobial pharmacological activity
(G. L. Daquet and Y. A. Chabbect, Techniques en bacteriologie (Bacteriological techniques), vol. 3, Flammarion Medecine Sciences, Paris, 1972 and W. B. Hugo and A. D. Rusell, Pharmaceutical Microbiology, Blackwell Scientific Publications, London, (1977)).
Culture medium and solvent:
Antibiotic medium no. 1 (seed agar) (Oxoid CM 327)
Tryptone-soya broth (Oxoid CM 129)
Ringer's physiological solution 1/4 (oxoid BR 52) Dextrose agar (BBL-11165) 0.1 N NaOH
Microorganisms:
"Bacillus subtilis" ATCC 6633
"Citrobacter freundii" ATCC 11606
"Enterobacter aerogenes" ATCC 15038
"Enterobacter cloacae" CHSP 20
"Escherichia coli" ATCC 10536
"Escherichia coli" R-1513
"Klebsiella pneumoniae" ATCC 10031
"Micrococcus flavus" ATCC 10240
"Proteus mirabilis" ATCC 4675
"Proteus morganii" CHSP 16
"Pseudomonas aeruginosa" ATCC 25115
"Pseudomonas aeruginosa" ADSA 47
"Salmonella typhimurium" AMES 98
"Salmonella typhimurium" AMES 100
"Sarcina Lutea" ATCC 9341
"Serratia marcescens" ATCC 13880
"Shigella flexnerii"
"Staphylococcus aureus" ATCC 5488/23
"Staphylococcus aureus" ATCC 25178
"Streptococcus faecalis" ATCC 10541
Preparation of the inoculations
Each of the microorganisms is seeded by streaking in tubes of Antibiotic medium No. 1 (seed agar), which are then incubated at 37° C. for 20 hours. Using a culture loop, the cultures are then seeded in tryptone-soya broth and incubated at 37° C. for 20 hours. The culture obtained is diluted to 1/4 with Ringer's physiological solution, so as to obtain a standardized suspension of 10 7 -10 9 cfu/ml for each organism.
Preparation of the medium containing the derivatives of general formula I
Starting from a solution of 1,000 μg/ml in 0.1 N NaOH, each product is diluted in Dextrose agar (previously melted and maintained at 50° C.), with successive dilutions so as to obtain the following concentrations: 64--32--16--8--4--2--1--0.5--0.25--0.125 μg of derivative/ml medium.
For each product, the solution of each concentration is subsequently distributed into Petri dishes 10 cm in diameter, with 10 ml of medium per dish and the same number of dishes as microorganisms to be tested.
As soon as the medium has cooled, the dishes are seeded with the inoculations using 0.4 ml of inoculation per dish. They are spread with a Driglasky loop and the supernatant is removed. The seeded dishes are incubated at 37° C. for 20 hours.
Results
The results obtained are shown in Table I. The products of Examples 1, 2 and 4 have an "in vitro" activity greater than that of pipemidic acid, with respect to both enterobacteriaceae (Pseudomonas aeruginosa) and gram-positive cocci. The derivative of Example 3 has an activity of the same order as that of pipemidic acid with respect to gram-negative microorganisms and a greater activity with respect to gram-positive cocci.
TABLE I__________________________________________________________________________MIC "in vitro" compared to pipemidic acidConcentrations are given in μg/ml. Compound of Compound of Compound of Compound of PIPEMIDICMICROORGANIAMS Example 1 Example 2 Example 3 Example 4 ACID__________________________________________________________________________Bacillus subtilis ATCC 6633 <0.125 <0.125 0.25 0.03 8Citrobacter freundii ATCC 11606 16 8 32 4.00 4Enterobacter aerogenes ATCC 15038 >64 8 >64 4.00 32Enterobacter cloacae CHSP 20 16 1 8 2.00 8Escherichia coli ATCC 10536 4 1 8 0.12 2Escherichia coli R-1513 16 4 16 4.00 16Klebsiella pneumoniae ATCC 10031 1 0.5 4 1.00 2Micrococus flavus ATCC 10240 16 8 4 1.00 >64Proteus mirabilis ATCC 4675 16 4 >64 8.00 16Proteus morganii CHSP 16 8 2 8 4.00 8Pseudomonas aeruginosa ATCC 25115 >64 16 >64 32.00 32Pseudomonas aeroginosa ADSA 47 >64 64 >64 >64.00 32Salmonella typhimurius AMES 98 0.5 <0.125 0.5 0.12 4Salmonella typhimurius AMES 100 4 0.5 8 0.50 8Sarcina lutea ATCC 9341 16 16 8 4.00 >64Serratia marcescens ATCC 13880 8 2 16 2.00 16Shigella flexnerii 8 2 16 2.00 4Staphylococcus aureus ATCC 5488/23 1 0.25 8 0.50 64Staphylococcus aureus ATCC 25178 1 0.25 4 0.50 64Streptococcus faecalis ATCC 10541 16 1 32 8.00 >64__________________________________________________________________________
Acute toxicity in mice
To determine this toxicity, C.F.L.P. strain albino mice of both sexes, weighing between 19 and 25 grams, have been used as experimental animals. After an 18 hour fast period with water "ad libitum" the derivatives which are the subjects of the present invention are administered intraperitoneally in 5% suspension in gum arabic. The volume of suspension administered has in all cases been 0.4 ml/20 grams (20 ml/kg), changing the concentration of the suspension according to the dose administered.
One hour after the administration of the derivatives, the animals are supplied with Panlab standard rat-mouse feed. The period of observation of mortality has been 7 days. None of the products has shown any differences between the sexes in respect of mortality.
The results obtained are shown in Table II.
TABLE II______________________________________ Administration LD.sub.50Derivatives route mg/kg______________________________________Example 1 i.p. >800Example 2 i.p. >1,600Example 3 i.p. 900Example 4 i.p. >1,000Nalidixic acid i.p. 600Pipemidic acid i.p. >1,600______________________________________
In view of their good pharmacological properties, the derivatives of general formula I are thus capable of being utilized in human and/or veterinary medicine, for the treatment of acute, chronic and recurrent systemic or localized infections, caused by Gram-positive and Gram-negative microorganisms which are sensitive to the products which are the subject of the present invention, in the gastrointestinal or genito-urinary tract, the respiratory apparatus, the skin and the soft tissues, as well as neurological and odonto-stomatological infections.
In human therapy, the dose suggested for the derivatives of the present invention is approximately between 400 and 1,200 mg/day for an adult, administered, for example, in the form of tablets or capsules. This dosage can, however, vary according to the severity of the ailment.
By way of example, two particular medicinal forms of the derivatives which are the subject of the present invention are shown below.
______________________________________Example of formula as a tablet6-fluoro-7-(1-pyrrolyl)-1-ethyl-1,4- 0.400 gdihydro-4-oxo-3-quinolinecarboxylic acidCarboxymethyl starch 0.018 gPolyvinylpyrrolidone K29-32 0.030 gMicrocrystalline cellulose 0.146 gColloidal silica 0.003 gMagnesium stearate 0.003 g 0.600 gExample of formula as a tablet6-fluoro-7-(1-pyrrolyl)-1-ethyl-1,4- 0.400 gdihydro-4-oxo-3-quinolinecarboxylic acidMicrocrystalline cellulose 0.0356 gColloidal silica 0.0022 gMagnesium stearate 0.0022 g 0.440 g______________________________________ | The present invention relates to new derivatives of 7-(1-pyrrolyl)-1-ethyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid and 7-(1-pyrrolyl)-1-ethyl-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid of general formula I: ##STR1## in which: X represents a carbon atom or a nitrogen atom, and
R represents a hydrogen atom or a fluorine atom, as well as their physiologicaly acceptable alkali metal salts or alkaline earth metal salts. The derivatives of the present invention are advantageously used as antimicrobial agents, espcially as anti-bacterial and anti-fungal agents. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/848,527, filed Sep. 29, 2006, entitled “Marketing/Fundraising/Reward System,” the entire disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
Charities and brand holders are always looking for new ways to achieve awareness and to generate revenue. An example of this was the Lifestrong(™) bracelets for cancer research. These yellow bracelets generated tremendous awareness and high donation revenue.
Soon other charities began making their own bracelets, e.g., for breast cancer education and research. These charities sought the same awareness and revenue rewards as achieved by the Lifestrong(™) bracelets. A great variety of bracelets for various charities of various colors and designs were then available to members, who were often overwhelmed and confused by the numerous available choices.
With multiple bracelets coming out for different charities, it didn't take long for scammers to figure out that they too could benefit by making bracelets. First, the scammers started making bracelets with different names and colors which implied that a legitimate charity was involved although no valid charity was actually involved. The scammers then moved on to directly counterfeiting the charities bracelets themselves. This caused not only reduced revenue for the charities, but also dilution of the charities' brands and thus dilution of the perceived value of the bracelets themselves.
It is thus desirable for a marketing/fundraising/reward system and method to provide for a product having aesthetic appeal, attractive personalization, anti-counterfeiting measures, and ease of identifying the charity.
It is also desirable that a marketing/fundraising/reward system and method provide for ease of determining what cause the member is supporting, the level of a member's support to a charity and a means of displaying that level to others.
It is also desirable that a marketing/fundraising/reward system and method provides for easy accounting of and addition to a member's support to a charity, and for easily accounting for and verifying rewards to the member either immediately, online or by mail.
It is also desirable that a marketing/fundraising/reward system and method deters theft.
SUMMARY OF THE INVENTION
One aspect of the present invention provides a marketing/fundraising/reward method and system, including a product provided to a member, the product having an incorporated authenticity tag, the authenticity tag including a personalized part, a unique number part, an encoded part, and a system identification section. A unique number is assigned to be displayed in the unique number part. The encoded part is encoded with the unique number. The member is allowed to provide content for the personalized part. System identity information is provided in the system identity section. A donation is provided a charity of the member's choosing, and information regarding the product, the donation, the personalized part, the unique number and the encoded part is recorded.
Another aspect of the invention includes the described system and method in which the personalized part includes at least one of a name, a pseudonym, a symbol or an image.
Another aspect of the invention includes the described system and method in which the encoded part is one of a barcode, an RFID, or another electronic device.
Another aspect of the invention includes the described system and method in which the recording is performed over a computer network.
Another aspect of the invention includes the described system and method in which the computer network is the Internet and the recording is done using a website.
Another aspect of the invention includes the described system and method further including authenticating the product using the recorded product, donation, personalized part, unique number and encoded part information.
Another aspect of the invention includes the described system and method further including providing an additional donation to the member's chosen charity by another person using the personalized part information and the system identification information.
Another aspect of the invention includes the described system and method further including generating a web page listing recorded product, donation, personalized part and unique number information, and displaying the web page. The web page may also be printed.
Another aspect of the invention includes the described system and method, and further allowing the member to add to the amount of their purchased product, and updating the recorded information accordingly.
Another aspect of the invention further includes providing rewards to the member by another party based on the authenticity tag information.
In an aspect of the invention the recorded information may be searched for the provision of the product to the member and when the provision cannot be found, indicating so on a display.
A further aspect of the present invention provides that the product provided to the member is a funeral car flag, and the personalized information includes the decedent's name.
Another aspect of the invention provides that the charity may be a for profit enterprise.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of a certificate of authenticity tag, in accordance with an embodiment of the present invention;
FIG. 2 is a schematic diagram of an exemplary marketing/fundraising/reward system in accordance with an embodiment of the present invention; and
FIG. 3 is a flowchart of an exemplary embodiment of the method of the present invention.
DETAILED DESCRIPTION
“Member” as used herein means any customer or entity which purchases one or more product embodying the present inventive system or method, without limitation.
The present invention advantageously provides a marketing/fundraising/reward system and method for a product having aesthetic appeal, attractive personalization, anti-counterfeiting measures, and ease of identifying the charity.
The present invention also advantageously provides for ease of determining what cause a member is supporting, the level of a member's support to a charity and a means of displaying that level to others.
The present invention also advantageously provides easy accounting of and addition to a member's support to a charity, and for easy accounting and verification of rewards to the member either immediately, online or by mail.
Reference is made herein and in the accompanying Figures to the Boomerang(™) system and to its associated and registered Internet domain and website, BOOMERANG.ORG. The Boomerang(™) system and its website form an exemplary embodiment of the present invention, and references thereto are for illustrative purposes only.
FIG. 1 is an illustration of a certificate of authenticity tag (hereinafter, “A-Tag”) in accordance with an embodiment of the present invention. The A-Tag 100 is typically printed on cloth and affixed onto a product. Other means of generating an A-Tag are also envisioned. In an embodiment, the product includes a cause design, charity name, brand name or logo.
In an exemplary embodiment, an A-Tag 100 includes a personalized portion 102 . As depicted in FIG. 1 , the personalized portion 102 typically includes the name of the charity/donatee 104 for which the member 106 purchased the product to which the A-Tag is affixed (hereinafter, “charity”), as well as the name of the member 106 . Alternatively, the member 106 may choose to use a pseudonym, symbol or other image instead of their name. Use of the term “charity” is intended in a very broad sense, and is not meant to imply that a “charity” must be non-profit. In some embodiments of the invention, it is anticipated that the role of charity will be taken on by a for-profit company or organization, wherein the fundraising aspect of the invention is overcome by the marketing aspect of the invention, and the organization may be interested in promoting a specific brand of merchandise.
The exemplary A-Tag 100 also includes one or more encoded sections, such as the two bar codes 120 , 140 depicted in FIG. 1 . In alternative embodiments, alternative encoded sections may be used, such as a 2-dimensional barcode, or an electronic device, such as an RFID (Radio Frequency Identification), a memory spot, or the like. The encoded section provides a unique identification number, which, as the name implies, may be encoded.
An exemplary A-Tag 100 also includes a system identification section 130 . The system identification section 130 provides information to any viewer regarding the A-Tag system being used, and preferably includes a reference to a website or domain name at which a viewer may obtain additional information and execute other functions, as further described herein.
FIG. 2 depicts an exemplary embodiment of a marketing/fundraising/reward system in accordance with the present invention. The Boomerang(™) system 200 includes one or more charities/donatees 202 , one or more members 204 , one or more products 206 to be associated with the charities/donatees 202 and purchased or obtained by the members 204 . It also includes A-Tags 208 , product 210 and other information, and provides functions as further described hereinbelow. The Boomerang(™) system also provides for other persons or entities 212 to access the website 210 to perform various functions, as described herein.
FIG. 3 is a flowchart depicting a typical series of operations within a system in accordance with an embodiment of the present invention. In the Boomerang(™) system 300 , a customer member joins and submits their information 302 , which is used to create and store customer account information 304 .
Next, the system updates the customer's information on its remote servers 306 . This update also takes place whenever the customer orders Boomerang(™) products or updates their account information 308 .
A time convenient for the customer or as appropriate for the system, the remote servers generate A-Tags for the customer as products are ordered 310 . The Boomerang(™) product is then assembled together with it's associated A-Tag and delivered to the customer 312 .
The customer may then interact with Boomerang(™) directly or through its partners at a partner or other location 314 , and information is gathered through scanning or other methods 316 . The collected information is then verified, and updated customer information is sent or access granted to remote locations 318 .
At the partner site, the updated information on partner records may generate discounts, rewards or donations 320 , which information is then transmitted to the Boomerang(™) system 322 . In an embodiment, the A-Tags 100 and their barcodes 120 , 140 or RFIDs lets the partner and the Boomerang(™) system 322 know what cause the member was wearing and thus what cause the partner should donate to.
Various advantages of systems in accordance with the present invention are illustrated in the following scenarios.
Scenario One—Anti-Counterfeiting:
Of particular importance are the methods used to limit counterfeiting. An embodiment of the present invention modifies the various products to be sold by adding several methods that will limit counterfeiting. For example, an exemplary product in accordance with the invention includes on its surface a place for a name, a pseudonym or picture, a unique identifying number and a corresponding barcode, RFID or similar device (hereinafter collectively referred to as an “encoded part”) encoding the number to be placed. Additionally, when a member orders a product, the member's name or other self-reference may be placed on a web page listing next to the unique number assigned. A member may also register their purchase on such a website, on which member purchases may be tracked.
In one embodiment of the invention, members receive A-Tags. These A-Tags may contain RFID's, memory spots or other similar devices with separate codes and numbers on them. Various levels of security may then be assigned and selected involving any of the product, the label, and the A-Tag in order for a member to have additional contributions made to their cause and to be eligible for special rewards, discounts, prizes and acknowledgements or for other uses.
Various embodiments of the present invention prevent counterfeiting, which robs a brand holder or charity of revenue and diminishes the brand. For example, the present invention increases the time, cost and effort required to attempt to counterfeit products incorporating the invention by reproducing the customized names, numbers and encoded parts used. If a counterfeiter did succeed in generating a counterfeit, the inventive system and method provides for relatively easy locating and shutting down of the counterfeiter by refusing to provide rights by the charity or by an intellectual property action.
Additionally, embodiments of the invention diminish any interest a purchaser would have in purchasing a counterfeit item. If a purchaser was to purchase a fake item, such as a shirt, the purchaser runs the risk of being found out by a friend, neighbor or co-worker, who may look up the purchaser's displayed unique number on a website and see that the purchaser's item is in fact a counterfeit and that the purchaser did not contribute to a charity at all. The fraudulent purchase may also be discovered if the purchaser wore the shirt to get into a sponsored event, or tried to get a discount, reward or have additional contributions made to the charity. The embarrassment that would befall the purchaser and perhaps even their family for stealing from the charity would certainly not be worth any potential savings they would have received by buying the counterfeit product. The counterfeit product might easily be detected and charges brought against the purchaser and the counterfeiter. In this way, by limiting counterfeiting, all the money that is supposed to go to the charity will go to them, and the meaning and value of their products will remain high and intact.
Scenario Two—Anti-Theft:
Another advantage of the invention is to deter theft. In an embodiment, when a product using the inventive system and method is stolen, and the thief or later buyer attempts to use the stolen item, it would quickly become apparent to their friends and family that the item was stolen because the personalized information would not match that of the thief or later buyer. Since a preferred embodiment of the invention includes personalized information on the face of the product, such as a name or picture, the stolen nature of the product becomes quickly apparent. Additionally, because the items all have a unique visible number, it would be potentially worthwhile and easy for a theft to be reported and for police and others to spot the stolen item. A list of stolen items may also be posted on the website. Also, without the corresponding A-Tags or encoded part, such as an RFID, winning anything using the stolen item would not be possible, and in fact would increase the risk of the thief being caught. Any reported theft could be noted on the website listing, showing the whole world that the item is stolen, and in fact the item number could be rendered invalid, thereby depriving the thief of any additional benefits. This also protects the value for the charity.
Scenario Three—Ongoing Donations:
Another benefit of the invention would be the potential for ongoing donations to the charity. Most charity products sold provide a one-time donation to the charity generated at the time of purchase. Embodiments of the inventive product are designed so that corporations and individuals have a mechanism in place for ongoing donations to be made. For example, products launched to provide relief from the devastation caused by Hurricane Katrina may generate an immediate donation upon purchase. There would also be numerous ways to provide ongoing donations. For instance, a department store may have a day where for every customer coming to the store with one of the inventive products and being scanned therein, the store would make an additional contribution to the customer's cause. The store gets great publicity, is linked to one or more good causes and pulls customers into the store. The customer gets the satisfaction of knowing additional contributions are being made on their behalf just by their showing up, having or wearing the product or making a purchase. The charity, of course, benefits through additional donations.
Scenario Four—Rewards for the Purchaser:
Another benefit of the invention would be the potential to win prizes for owning/wearing a product incorporating the invention. They might win prizes such as gift cards, sample products from corporate sponsors, free concert or movie tickets, points redeemable for later merchandise purchases, or free music downloads. In the example above, the department store might even grant customers with the product discounts on purchases.
Scenario Five—Cause Awareness/Level Playing Field:
Another benefit of the invention is to promote awareness of various causes. This may be accomplished by use of a website and by various links to other sites or sources of information. Of even more importance, Boomerang(™) becomes a new way to revitalize interest in and show what causes are important to a member. As people see a Boomerang product and logo, they will naturally look to see what design is attached to it. Conversations may start about the causes and this is especially true for designs that are not as easily recognizable. Additionally, the Boomerang(™) structure works equally well for very well known causes as for less well know causes. Boomerang(™) in fact becomes a vehicle for learning about various causes. Boomerang(™) also works very well whether the cause is small or large, and is thus a very democratic system.
Another benefit of the invention is the collecting and displaying of encoded parts, such as A-Tags or RFIDs. These tags themselves show the taste and charity of the member. These tags might be released in a decorative and collectable form such as in jewels or metallic jewelry and can be proudly displayed on bracelets, necklaces, key chains, etc., and are available in a variety of styles, materials and pricing. Some customers collect as many tags as possible to show their degree of support. Others collect tags that represent each of the different products produced for each of the different causes.
In an embodiment of the invention, the A-Tags can be used to verify membership and provide access to members having or wearing the A-Tags. As described, these A-Tags would have an RFID, memory spot or similar device and are unique to that member, with the member's information stored by the company operating the system. These A-Tags can then be used for verification purposes or to activate remote access devices to access that member's account and information. Access would be more secure in conjunction with a secondary authorization such as entering a PIN number or fingerprint authorization. The member could access their account for a variety of uses.
One such use would be creating forward interactive screens. On the system's website, the member could create the type of user interface screen he would like to access remotely. This setup could include the screen color and graphics, any sound clips, audio clips, video clips, welcoming messages, the screen's remote capabilities, etc. This all would be accessed at the system's outside terminals, the member's computer or others, an ATM, other payment systems, etc.
Another embodiment of the invention rewards and recognizes customers/members based on their level of support. This information will be available on the website and can be displayed right on the labels of the customers/members purchased products or accessed through the barcodes or A-Tags. Various benefits may inure to customers/members based on their level of support. This increase in levels need not be dependant on the customer/member support for any single cause, which allows customers/members to increase in level more easily.
In embodiments of the present invention, the use of barcodes, RFIDs, memory spots or other similar device allows the system to work with partners in unique ways to encourage additional contributions to the causes and rewards to the member. They also provide an easy way to track members, who they support, contribute to that cause, and provide benefits to the member instantly or through mail or email.
Another embodiment of the present invention is the production of common products such as car flags, lawn flags and car magnets. An inexpensive way to manufacture personalized, individualized, customized or limited edition flags, etc., is by printing on customizable paper, laminating it and attaching it to a flagpole or to magnets. Various items may be added before the lamination process, such as ribbons, fabric, buttons, stars, hair, blood, etc., to create three dimensional flags.
Outside its uses for charities, embodiments of the present invention include possible use for licensed celebrity products. For example, if a fan was buying tickets for a Green Day concert at Giants stadium (Green Day is a popular band), they would be given the option of buying a Green Day flag or T-shirt, which may be designed by Green Day. The product would have among other items the date, venue and name, unique identifying number, unique name/picture and barcode/RFID. Fans could proudly show that they are indeed fans, that they're going to that concert or that after the fact that they've gone to that concert. In the days leading up to the concert, as a concert promotion, radio stations might give away prizes to fans whose vehicles are spotted with these flags, who are wearing T-shirts or who are picked by number. On the day of the concert, these fans would all be driving proudly on their way to the concert with their customized flags, etc. and in the parking lot looking for other vehicles that also have the flags. Certain benefits could be awarded, such as discounts on parking, free drinks, etc. For any given concert a local radio station's name or other advertiser could be added to the products.
Scenario Six—Funeral Car Flags:
Yet another embodiment of the invention includes making inexpensive car flags for funerals. It is typically very difficult for funeral processions to stay together. Cars that are not part of the procession often cannot tell it's a procession and thus cut into it. Also, people in the procession do not have an easy way to tell which cars are in its procession. In the past, cars in a funeral procession turned on their headlights to at least let other cars know that they were part of the procession. Today, many cars in the procession forget to put their headlights on and, far worse, most new cars are equipped with daytime running lights that are on all the time. This renders the car headlight option somewhat obsolete.
A substitute for using headlights has been placing bumper sticker sized banners on the front dash or rear window area. If these can be seen it can potentially help the participants in a procession stay together, but it is difficult to see these banners. Additionally, they are almost of no use in helping other vehicles identify that it is a funeral procession.
The best available option has been flags that are attached to the vehicles in the procession. They are usually made of cloth and are relatively expensive, and usually attached to the vehicles by magnets. Because they are not cheap, they are usually put on by the funeral director at the funeral home and collected by the funeral director at the cemetery. There is some indication that these flags are not in widespread use, and that funeral homes typically do not charge for them and therefore do not profit from using them.
Flags manufactured in accordance with the present invention are relatively inexpensive and are customizable to that particular funeral. Typically, the same information that goes on the cemetery stone may be displayed on the flags: the name of the deceased, birth and death dates, and something about them. In addition, there may also be a picture of the deceased as well, and optionally the name of the funeral home. Thus, the funeral home would initiate the flag order with basic information. The order may simply be complete at this point or the deceased family will have the ability via a user name and a password to get into a website, where they would be able to choose from a variety of templates as to what goes on the flag, change the text, and even download a picture of the deceased.
Because the flags are personalized, they will not only identify the procession to outside vehicles, but will also allow cars within the procession to quickly identify their procession even if there is another procession, as is increasingly likely near the cemetery itself. The personalized flags also create an impressive regal look for the deceased family. Everyone in the procession and possibly others will receive a flag. The flags are also designed to be easily removed from the flagpoles, leaving behind a remembrance of the deceased and the service. Thus, the personalized flags perform multiple functions.
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 is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | Provided is a marketing/fundraising/reward method and system including providing a member with product with an incorporated authenticity tag including a personalized part, a unique number part, an encoded part, and a system identification section, assigning a unique number to be displayed in the unique number part, encoding the encoded part with the unique number, allowing the member to provide the personalized part, providing system identity information in the system identity section, providing a donation to a charity of the member's choosing, and recording information regarding the product, the donation, the personalized part, the unique number and the encoded part. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to physically non-distributed microprocessor based systems and, more particularly, the communication channel between functional components within a class of computer systems commonly known as personal computers.
A personal computer (PC) is comprised of several major functional components which may be basically defined as a microprocessor, a read/write memory (RAM), a mass storage device (e.g., hard drive or CD ROM), and an input/output (I/O) device (e.g., display, serial port, parallel ports, etc.). These functional components within the PC are interconnected by, and communicate via, a parallel data/address bus which is usually as wide as the processor data I/O path. The bus is typically of fixed physical length comprising a number of parallel copper traces on the PC's motherboard. In addition, there are provided a number of fixed tap points to the bus, e.g., edge connectors, din connectors, etc., to allow the customization of the PC's configuration by adding peripheral functions, memory, etc., or removing unused functionality.
While a bus provides a simple-minded mechanism for customization and communication within a PC, it has several limitations and unique problems associated with it. First, a bus is by nature, single transaction (e.g., only one functional unit can communicate with another at any given time and during this time, no other functional units can communicate with anything) and sequential (messages follow one after the other with considerable handshaking between functional units). A second problem of a bus is that all functional units connected to the bus must meet the electrical specifications and requirements of the bus even if these specifications and requirements are quite dated, technologically. Thirdly, because the bus is a generic interconnect in nature, it can not be truly optimized for communication between any specific subset of functional units without adversely affecting communication performance between another subset of functional units.
Fourth, the speed of the bus is substantially slower than might otherwise be obtainable. This is due to two primary issues: First, busses are composed of relatively long lengths of parallel traces in close proximity to one another and this results in high parasitic capacitive coupling between traces of the bus (i.e., electrical noise). This noise increases as the frequency, or speed, of the bus increases. Thus, noise margin requirements restrict the speed (and length) of the bus. The second issue relates to the unknown and highly variable electrical loading of the bus. The speed of the bus is inversely proportional to the capacitive load on the bus. This capacitive load is determined by the number of electrical connectors on the bus and the number of electrical connections to the bus. Since these numbers are variable, designers typically engineer the bus for worst case constraints. That is, the bus is typically slowed down to a rate that would sustain a worst case loading situation even though this may occur in one PC in a thousand.
Other major drawbacks of a bus are the need for electrical handshake signals and its fixed electrical data width (i.e., 8 bits, 16 bits, 32 bits, etc.) Handshake signals typically include READ, WRITE, MEM, I/O, WAIT/READY, etc. These signals are physical and are used to inform and control functional units (i.e., inform of the type of request, and control/synchronize between communicators.) Fixed data width limitations become problematic as chip data path widths exceed the width of the bus. As will be seen herein, defining handshaking and data size at the physical layer is less flexible than would be desired.
With the ever increasing demand for data manipulation in such applications as multimedia or graphics programs, the bottleneck of the bus becomes more acute. There have been many attempts to address and remedy this problem (e.g., VESA, Video local bus, PCI, etc.) but no solution offers greatly improved performance and complete scalability.
The present invention provides a system with the configuration flexibility of a bus-based PC while reducing the electrical problems. Commensurably, interfunctional-unit communication speed and flexibility are greatly enhanced. The present invention applies a point-to-point packetized interconnection structure to facilitate communication between functional units (e.g., processor, memory, disk, I/O, etc.) within a PC.
Because it is point-to-point, the interconnections scheme of the present invention is of relatively fixed electrical load and can, therefore, be optimized for speed. Furthermore, the packet protocol that will be more fully disclosed herein provides a means of eliminating the typical physical layer control signals of a bus and replacing them with link-layer control which is much more flexible.
In order to allow for interconnecting more than two functional units, the present invention may be expanded by any of several interconnect topologies, e.g., switches, rings, etc. Where speed and a high degree of parallel traffic is desired, a switch topology provides the best means, e.g., crossbar switch. If speed is important but parallel traffic patterns are not very common, a shuffle-type switch may make the most sense. In applications that are very cost sensitive, the present invention may also be expanded by means of a ring topology.
As will be made clear in the specific disclosure portion of this document, the packetized point-to-point interconnection scheme of the present invention improves speed and performance at reduced cost and with better noise characteristics (both internal electrical noise and radiated EMI) as compared to the bus interconnect currently employed within a PC.
Therefore, it is an object of the present invention to provide a new and improved PC, specifically, improving internal communication between microprocessor, memory, mass storage, I/O, etc. or any subset of these functional units. It is further an object of the invention to improve communication speed within a PC. It is further an object of the invention to reduce interconnection electrical noise within a PC. It is further and object of the invention to provide a more flexible interconnect means within a PC.
Accordingly, it is a general object of the present invention to provide a new and improved PC, specifically improving internal communication between microprocessor, memory, mass storage, I/O, etc. or any subset of these functional units.
It is a more specific object of the present invention to provide improved communication speed within a PC.
It is a still more specific object of the present invention to reduce interconnection electrical noise within a PC, and to provide a more flexible interconnect means.
SUMMARY OF THE INVENTION
The invention is directed to a physically non-distributed microprocessor-based computer system, comprising a microprocessor, a random access memory device, a mass storage device, an input-output port device, wherein the devices are each being operable in conjunction with the microprocessor and include an interface for receiving and transmitting data in packet form, and which further comprise a packet-based data channel extending between the microprocessor and the interfaces of the devices for providing simultaneous bi-directional communication between the microprocessor and the devices.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which:
FIG. 1 is a block diagram of current PC systems which use a bus based interconnect.
FIG. 2 is a conceptual block diagram of two packet nodes and a physical link.
FIG. 3 is a general block diagram of a packet.
FIG. 4 is a detailed diagram of the packet header showing each of the fields.
FIG. 5 is a general block diagram of an Idle packet.
FIG. 6 is a general block diagram of an Request packet.
FIG. 7 is a general block diagram of a Request Echo packet.
FIG. 8 is a general block diagram of a Response packet.
FIG. 9 is a functional block diagram of a link interface showing all the necessary elements.
FIGS. 10a and 10b show the possible structures of a request queue shown in FIG. 9.
FIGS. 11a and 11b show the possible structures of a response queue shown in FIG. 9.
FIG. 12 shows the structure of a linc cache shown in FIG. 9.
FIGS. 13a and 13b show possible implementations of the linc using discrete link interface chips.
FIG. 14 shows a processor with an embedded link interface connected to system memory through another link interface.
FIG. 15 shows detailed structure of the Idle packet for processor memory I/O.
FIG. 16 shows detailed structure of the request packet for processor memory I/O.
FIG. 17 shows a detailed structure of a Request Echo packet for processor memory I/O.
FIG. 18 shows detailed structure of a Response packet for processor memory I/O.
FIG. 19 shows sample request packets for a load and store instruction.
FIG. 20 is a detailed schematic of the processor node interface chip transmit half.
FIG. 21 is a detailed schematic of the processor node interface chip receive half.
FIG. 22 is a detailed schematic of the memory node interface chip receive half.
FIG. 23 is a detailed schematic of the memory node interface chip transmit half.
FIG. 24 shows a possible ring interconnect topology for packet nodes.
FIG. 25 shows a possible switched interconnect topology for packet nodes.
FIG. 26 shows possible structures of response packets for a given request in response to conditional branch or jump in program code.
FIG. 27 is a flow graph of the processor node receive protocol.
FIG. 28 is a flow graph of the processor node transmit protocol.
FIG. 29 is a flow graph of memory node receive protocol.
FIG. 30 is a flow graph of memory node transmit protocol.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the Figures, and particularly to FIG. 1, a node is defined as any device or group of devices which perform a specific system function within a microprocessor system. Such nodes typically have a physical address or addresses with which they are associated. Examples of such nodes include a processor, a memory, an input/output device, a hard disk, etc. The object of this invention is to interconnect all, or some subset of all, nodes with a high speed message passing packetized interconnection channel.
FIG. 1 depicts the simplest implementation of the prior art. Processor node 40 is connected to bridge node 41. Bridge node 41 is further connected to memory node 42. Bridge node 41 also provides an interface to system bus 43 in order to allow processor node 40 to communicate with peripheral nodes 44, 45, 46 and 47 over the bus.
The high speed message passing packetized interconnect channel and protocol is intended to allow asynchronous communication between any two nodes, so equipped, in any system configuration using packets of data or instructions. FIG. 2 shows a logical conceptualization of a node. The functional unit 48 may be any of the elements of FIG. 1. Interface 49, which is the embodiment of the present invention, provides a seamless interface between functional unit 48 and the physical layer 50. Physical layer 50 connects to any other packet node 51, thereby, in conjunction with interface 49, allowing communication between any group of functional units of FIG. 1.
Thus, the present invention makes each node in a computer microprocessor/microcontroller based system interface with each other using a uniform packed based message passing interface. The invention creates packet nodes which speak the same language electrically and logically. This simplifies communication and minimizes traditional handshaking and overhead. Therefore, significant data-rate speedup may be gained because rather than being pigeonholed into a hardware restricted, single transaction, high overhead interconnect (i.e., a bus), the present invention allows messages of varying length (rather than single transaction) with flexible handshaking, and minimal overhead. Or, more precisely, the present invention allows for more intelligent and flexible information exchange between nodes while requiring only that overhead and handshaking required for a specific transaction. The present invention does not impose, as does a bus, a set of costly rules and formalism that must be adhered to even if it makes no sense for a specific transaction.
Again, with reference to FIG. 1, current systems communicate at the hardware level, i.e., the processor node 40 issues commands on the processor bus which must then be converted from the virtual address that the processor understands to a physical address by bridge 41. This, information is then further converted by bridge 41 prior to being placed on the bus 43. At this point, all other nodes, 42, 44, 45, 46 or 47 on the bus look to see if they are being addressed by processor node 40. The one node that is in fact being addressed, acknowledges the processor query and then takes action based on that query. Upon receiving the acknowledgment from the queried node, processor node 40 now may take appropriate data action (i.e., output data, input data, etc.) and the transaction is assumed to be completed. Next, the process can repeat in exactly the same manner, even if the query is to the exact same node as previously addressed. This is the handshaking and overhead bottleneck of a conventional bus. Furthermore, whenever the bus is being utilized by a pair of nodes, all other nodes are prevented from communicating with any other node. The present invention stems from the realization that the byte by byte handshaking and transmission that is typical of a bus-based system is greatly inefficient and constraining and may be vastly improved upon.
In accordance with the invention packet based message passing techniques are applied to the nodes within a microprocessor based system. With reference to FIG. 2, the following is a simple illustration of the invention's operation: Execution unit 48a (e.g., processor node) requests information from execution unit 48(b) (e.g., memory node) via link interface 49(a). Link interface 49(a) assembles a packet requesting said information (i.e., its address in memory, amount of data requested, etc.) and then rapidly transmits said packet to link interface 49(b) via physical interface 50 (which may be single-ended line drivers, low voltage differential drivers, or any other method common in the art). Link interface 49(b) then decodes the packet and takes the necessary steps to process the request with respect to execution unit 48(b). Link interface 49(b) then collects, from execution unit 48(b), all data necessary to fill the request, packetizes the data into a response, and then, when the request is filled, ships the data back to link interface 49(a) via physical link 50. At this point, link interface 49(a), depacketizes the data and provides it to execution unit 48(a) in a manner befitting the execution unit's request. Thus, the physical link is only tied up for the time when useful information is actually being sent. Furthermore, requests for several pieces of data result in less physical interface bandwidth utilization since the several pieces of data are streamed in the same message.
A packet node in the present invention communicates with another packet node using "packets." Each packet contains all the necessary information that is required for the intended receiver without the added overhead of setting up the receiver or formatting the data to a node-specific set up.
The structure of a packet 55 such as shown in FIG. 3 may have, for example, the following general characteristics:
1) Packet components 52 and 53 are of 16 bits (2 bytes) in width and referred to as a packet word.
2) Header 52 has means for indicating that the next packet word is an extension of the header 52. This means is the extended header bit 54.
3) A packet body 53 which can be anywhere from 0 bytes to 256 bytes in length.
4) The maximum size of a packet 55 is 258 bytes.
5) The width of the packet remains the same regardless of the width of the channel (i.e., for wider channels, more than one packet word may be sent in parallel.)
The above definitions may easily be changed without affecting the nature of the invention.
FIG. 4 details the fields within the header packet. The type-of-packet field 59 defines one of four fundamental packet types that are exchanged between any two nodes. These are 1) IDLE, 2) REQUEST, 3) REQUEST ECHO, and 4) RESPONSE. The type-of-instruction field 58 indicates the action that needs to be taken by the receiving node of this packet. Examples of such actions include load, store, input, output, read, write, and other system level interfunctional unit operations.
The size-of-device field 57 is to allow for the interface between devices of different physical data widths with minimum physical layer transmission time. By knowing the size of a requesting node device, the interface circuitry of the receiving node can pack the data into a packet in the most efficient manner for decoding by the requesting device and only send portions of the overall required response that are filled, where `filled` is defined as sufficient to meet the width of the requesting node device as defined in the size-of-device field.
The flow control field 56 contains the size-of-response, node ID, extended header bit, and BUSY/OKAY status bit. The size-of-response indicates the amount of data being requested. The node ID indicates the logical functional unit for which this packet is intended. The extended header bit allows for headers greater than 2 bytes in size, where necessary. The BUSY/OKAY status bit indicates whether the receiver of request packet can accept and service the packet.
Having defined the fields of the header packet, we now define the four fundamental packet types. The IDLE packet 55a, FIG. 5, contains only the header and no data and is continually sent out by the idle node. A node receiving the IDLE packet may then use the idle link for transmitting data that the receiving node believes the idle node may need based on the idle node's prior request history.
It is informative to illustrate the use of IDLE packets with an example. Assume that the processor node has been requesting sequential data blocks from the memory node. At some point in time, the processor node stops requesting data from the memory node because the processor node has to do something else (e.g., service an interrupt). At this point, the processor node sends idle packets to the memory node. Upon reception of the idle packet, the memory node reviews the history of processor node requests and may continue to send data based on a projection of the history of the processor node requests. These unrequested data are then stored in the processor node link interface cache provided the processor node has not specifically requested some data from any other node. In this way, idle links can be used most effectively to transmit data that may be needed before it is requested.
A second type of packet is the REQUEST packet 55b, FIG. 6, which has been informally referred to throughout this disclosure. This packet is transmitted between any two nodes to indicate or request an action from the receiving node for the requesting node. The request packet contains a header (see FIG. 3, element 52) that has the ID of the requested node in the flow control field and the type of instruction for the receiver to execute, e.g., load, store, etc. The request packet also contains a body (see FIG. 3, element 53) to the extent that there is data sent by the requesting node to the receiving node for the receiver to perform the requested instruction.
The REQUEST ECHO packet 55c, FIG. 7, is sent by the receiving node to acknowledge reception of a REQUEST packet 55b. This packet is primarily for indicating whether the request from the requester can be catered or not. Within the header of the request echo packet, in the flow control field, the REQUEST ECHO packet indicate whether the receiver is busy (busy echo) or able to service the request (okay echo).
The last packet type is the RESPONSE packet 55d, FIG. 8. This packet is used to respond to a REQUEST packet. The header of the RESPONSE packet contains the node ID of the intended receiver (i.e., the original requesting node) and other information regarding flow control, etc. The body of the response packet contains the data requested to the extent it is required and the body of the RESPONSE packet is no longer than it needs to be to hold said data.
A typical transaction between any two nodes (node a and node b) shown in FIG. 2 is summarized below:
1. Node A generates a request packet for Node B.
2. Node B, based on whether Node B's request queue can cater to the request, sends one of two messages back.:
a. If it can cater to request from Node A then sends Node B a REQUEST ECHO OKAY packet.
b. If it can not cater to a request from Node A then Node B sends a REQUEST ECHO BUSY packet.
3. If Node A receives a REQUEST ECHO OKAY packet then Node A takes no action on the original request. If Node A receives a REQUEST ECHO BUSY packet then Node A resends the original request.
4. If REQUEST ECHO OKAY was sent by Node B, then Node B sends a RESPONSE packet to cater to the original request. This completes the transaction between Node A and Node B.
If no action is required from either Node A by Node B or from Node B by Node A, then IDLE packets are exchanged between them. Node A sending an IDLE packet to Node B or vice a versa are both independent operations. The IDLE packet may also be used to exchange configuration/status/control information of each node.
To extend the capability of the present invention to an arbitrary number of nodes requires an expanded interconnect. FIG. 24 and FIG. 25 depict two possible interconnection schemes.
FIG. 24 shows a topology commonly referred to as a ring interconnect 67. In this type of interconnect, each link interface's physical link output is connected to a neighboring nodes link interface physical input until the ring is closed. For this type of implementation, the link interface must implement a pass-through mechanism. That is, each link interface must compare its node ID to the node ID of the packet header. If the compare is not successful, the link interface must forward the packet just received on its physical link input to its physical link output. In this way, packets circulate in the ring until they arrive at their ultimate destination. This receive-check-forward mechanism is functionally similar to that described in the IEEE 1596 (SCI) specification (Elastic Buffer).
To improve performance over a ring, FIG. 25 shows another common interconnect topology commonly referred to as a switch 68. The switch 68 of FIG. 25 may be a crossbar switch, a shuffle switch, a broadcast crossbar switch, or similar device. Implementations of crossbar switches are well known to the art and it is sufficient to describe a cross bar as N, M to 1 multiplexers, where N is the number of output ports and M is the number of input ports. When a crossbar switch is used, each link interface must check the node ID of the received packet to guarantee that the packet is intended for the receiving node. This straightforward modification to the link interface physical link input circuitry is to include an ID decoder in the receive logic before queuing the request.
FIG. 9 depicts a functional diagram of the link interface 49. The Host Interface 60 provides the means to connect the link interface to the bus of the functional unit 48 (i.e., processor, memory, I/O, disk, etc.) This part of the link interface contains all the necessary hardware to handshake with the functional unit node and is specific to the said functional unit. It also provides for all necessary signals to complete bus cycles needed for the functional unit.
The Store Accumulator 61 is responsible for packing data into a packet body for the STORE instruction. This is especially useful when the processor node is doing a burst write. In this case, the several data and addresses that are sequentially output by the processor are accumulated by the Store Accumulator 61 of the link interface and packed into one store message packet. Thus, a single message transaction results in several data being stored by the receiving node.
The Control block 62 provides for control of the internal components of FIG. 9 as well as coordinating the functioning of the physical link. Control block 62 is essentially a state machine that keeps track of the link state and provides the necessary housekeeping functions of the link. Control block 62 also contains the history register which is used by the requester in conjunction with the Linc Cache 63 `hit` information to determine the desired size-of-response for a given request. This same register is used by the receiver to determine how much data and from where said data may be returned when the receiver detects an IDLE packet. The detailed operations that Control block 62 performs are disclosed in association with the operation of each the blocks of FIG. 9 and the link interface.
Request Queue 64 provides buffering and storage for all accesses coming from a functional unit 48. These accesses can either be stored in raw form (node address and data format), or in packetized form, depending upon the access arrival rate. That is, based on the rate that accesses come into the link interface from the functional unit 48, the access may be stored raw and then packetized as the access is converted to a request packet and placed on the physical link or the access may be packetized prior to being placed in the queue. With reference to FIG. 10, if the access is being stored as a packet in the Request Queue 64, the queue is configured, as in FIG. 10a, to be two bytes wide plus one bit for frame. The frame bit 67 is used to indicate the presence of header on the current cycle. If the access is being stored raw, then the request queue is reconfigured to be as wide as the functional unit's address width 68 plus data width 69 plus the instruction field width 70 as in FIG. 10b.
The Echo Waiting Queue 65 of FIG. 9, is operable to function as storage for outstanding Request packets. These Request packets are copied into the Echo Waiting Queue 65 until an ECHO OKAY packet is received from the node catering to the request. Storing outstanding requests provides the means for the Control Block to handle out-of-order RESPONSE packets and to verify link integrity by making sure that all requests are being responded to.
The Response Queue 66 has a structure similar to the Request Queue 64. It may be configured as in FIG. 11 and its operation is the reverse of the Request Queue. The Response Queue can store either packetized information as received from the physical link for later depacketization and passage to the functional unit (function unit data-need is slow), FIG. 11a, or information received from the physical link may be immediately depacketized and stored raw for delivery to the functional unit (functional unit data-need is fast), as in FIG. 11b.
Linc Cache 63 is basically a directed mapped cache for caching response data for the functional unit. The size of the Linc Cache 63 is an integer multiple of the maximum data packet size 53, i.e., m×256. To keep track of the latest data, the Linc Cache 63 is partitioned into two identical blocks; one block containing the latest information 71 and the other block containing the information received before and up to the latest update 72.
With reference to FIG. 12, each block of the Linc Cache 63 is of fixed size (width 73 and depth 74). However, the Linc Cache line 75 size is variable. Furthermore, the Linc Cache line size is always at least as long as the functional unit's cache line 76 size. There are N words in a Linc Cache line, where N is dynamically variable. If an access from the functional unit misses in the Linc Cache, the link interface will request the data from the proper node. The amount of data requested by the link interface, N, depends on the history of the `hit` rate within the Linc Cache. If the hit rate is high, the control circuitry increase the Linc Cache line size thus maximizing data transmission per physical link transaction. If the hit rate is low in the Linc Cache, the Linc Cache line size is reduced in order to reduce the size of messages on the physical link.
The motivation for this unique and counterintuitive approach to cache management is the realization that if the hit rate to the Linc Cache is low, the accesses are almost certainly not sequential and are unpredictable. Thus, increasing the Link Cache line size will probably not improve the hit rate. Therefore, the invention reduces the line size (which will probably not hurt the hit rate but will make the link available for all nodes more often since message sizes from this node will now be smaller).
FIGS. 13 and 14 depict two possible embodiments of the link interface 49. FIG. 13 shows an implementation wherein the link interface is separate from any of the node's circuitry. FIG. 13a shows an implementation where the physical link is on a motherboard or external physical channel with link chips for each node. The link chips in FIG. 13a only contain the link interface 49. FIG. 13b shows an implementation where the physical link is embedded inside a single chip or a linc chip 39. The linc chip 39 contains both a link interface 49 and the physical link or channel 50. FIG. 14 shows an implementation wherein the link interface associated with the processor node is include within the processor silicon itself. FIG. 13b will be discussed first.
FIGS. 20 through 23 show a detailed implementation of a link interface. With no loss of generality, the interconnect is assumed to be a two point, point to point interconnection between a processor node and a memory node. It will be shown in the description to follow how the memory node interface may be extended to include any peripheral device
FIGS. 20 and 21 depict the transmit and receive, respectively, link interface circuitry for the processor node. With respect to FIG. 20, the transmit operation starts when the processor node (host) begins a bus cycle. The transmit circuitry latches the necessary data and address information into latch 201. As the data and address are being latched, the bus cycle of the processor node is decoded to be either a read or write (load or store). In either case, control circuitry 204 enables the appropriate header from header pool 207. This header pool encodes all possible header types since the type of processor is known to the specific implementation of the link interface and allows for faster assembly of a packet. The header is put in the request queue 202 and then the address/data/control of the bus cycle is mapped to the packet as it is put in the request queue 202. The request queue 202 operates in a first in, first out (FIFO) manner. If the cycle is deciphered to be a store then the request is stored in the store accumulator 205. After the store accumulator 205 is full the control attaches a header to the information in the store accumulator 208 and sends it out on the physical linc 50. Once any request has been sent out, it is queued in the echo waiting queue 203 to await the receipt of an ECHO OKAY. During the queuing of a request, when a load or read request is received from the processor node, there is a search done in the linc cache 206 and the store accumulator 205 to determine whether the request can be catered to without going out on the linc (i.e., check to see if a linc cache hit occurs).
Referring to FIG. 21, in the receive operation, once a packet is received over the physical link, the intelligent latch 208 and demultiplexer 209 combination allows depacketization of the incoming information and the storing of the data/address in the linc cache 206. Because of the variable linc cache line size, the returning requested data will be more than the original processor required amount (to fill the larger linc cache line). Finally, the control 204 issues the appropriate bus and control signals to satisfy the processor node request.
The receive operation for the memory node with respect to FIG. 22 is described below. The data comes in on physical link 50 and latch 208 takes the data and appropriately fills the request queue 210. The request queue 210 contains the raw request which then goes to the memory controller 211 for the appropriate action. The design and implementation of the memory controller is specific to memory devices being used and the system memory architecture. Once a load request has been received, the controller 209 checks the linc cache 212 to see if the data is ready to be packetized and sent across the physical link 50. This saves cycles since it is not necessary to assert the appropriate control signals to start the memory access cycle if there is a hit in the linc cache 212. If the request received is a store request, then it is directly sent to the memory controller 211 for appropriate action.
The transmit operation with respect to FIG. 23 is briefly described below. Once a request is received, header pool 213 is indexed to provide the appropriate header for the response packet. The request that was received over physical link 50 and stored in the request queue 210 is dequeued and the response is then taken out of the linc cache 212 or the memory and packetized by attaching the appropriate headers and put into the response queue 214. The response queue has a FIFO operation similar to any of the other queues used in the current implementation and so the response will be sent when it is at the head of the queue.
It is important to realize that FIGS. 22 and 23 describe an Functional Unit specific implementation embodying a memory node. With the addition of a store accumulator and the appropriate controller that replaces the memory controller 211 in FIG. 22, this circuitry can be adapted to Functional Units of any type on any node.
The protocols used for communication between the processor node and the memory node are described in the flow graphs in FIGS. 27, 28, 29 and 30. These protocols are:
1) Processor node Protocols
a) Receive Protocol (FIG. 27)
b) Transmit Protocol (FIG. 28) and
2) Memory node Protocols
a) Receive Protocol (FIG. 29)
b) Transmit Protocol (FIG. 30)
The flow graphs in conjunction with the description described herein describe the functioning of the link between the processor node and the memory node.
FIG. 14 depicts a provision of the link interface on the same silicon as the processor. This results in several important simplifications and improvements. Moving inside the processor silicon allows the link interface access to the Translation Lookaside Buffer (TLB) and the Branch Target Buffer (BTB) which allows the implementation of sophisticated prefetching and caching schemes.
Microprocessors typically do speculative execution based on the load/store instructions in a program. For standard arithmetic logic unit (ALU) operations, it is relatively easy to identify the register operands needed to be accessed during the instruction decode phase itself. However, for memory access operations, significant improvement is possible. In particular, the determination of the memory location that needs to be accessed requires an address calculation. The load/store instructions are issued to a pre-execute engine where address calculation is performed. After address calculation, the virtual address is translated into a physical address, if necessary. This address is then issued to the memory interface of the processor to form the appropriate request.
By moving the link interface inside the processor, access is gained to TLB which stores a lookup table or cache translation descriptors of recently accessed pages. This information is very valuable in doing intelligent memory prefetches because now the link interface can look at the TLB and decide the location and access size of prefetches.
When the link interface is within the processor, the interface also gains access to the BTB. This allows two important benefits. First, in any given program or code, there typically is a branch or jump every five instructions, on the average. The branch prediction mechanism of the processor allows the processor to do speculative execution by predicting where it needs to go four or five instructions ahead of the current program counter (PC). When the branch predictor is wrong, there is a huge performance penalty in the processor because of stalls and pipelines running empty. By having access to the BTB, the link interface knows all possible outcomes of the branch and can prefetch data/instructions for all of the possible outcomes and have this information available at the processor. In this way, performance penalties due to branch prediction errors are significantly reduced. This implements a virtual zero wait-state operation to memory on a branch miss.
Second, in the rare event that there are no jumps in the program, FIG. 26 shows a method of obtaining performance improvement. Rather than fetch a large block of data from a single address, each packet would be configured to fetch several smaller blocks of data from several different addresses. In this context, "data" means both program data and processor instructions.
For all of the above detailed embodiments of the invention, FIGS. 15, 16, 17, 18 and 19 show the specific implementations of the packet structures along with which fields of the header are active for each packet type.
While a particular embodiment of the invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made therein without departing from the invention in its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. | A physically non-distributed microprocessor-based computer includes a microprocessor, and a random access memory device, a mass storage device, and an input-output port device, all operable from the microprocessor and including an interface for receiving and transmitting data in packet form. A novel packet-based data channel extends between the microprocessor and the interfaces of the devices to provide communication between the microprocessor and the devices. By varying the size of the packets in accordance with actual data transmission requirements improved computer performance is achieved. | 7 |
FIELD OF THE INVENTION
The present invention relates to laser beam monitoring devices, and in particular to a refractive element that provides a plurality of detector beams of varying power and energy levels.
BACKGROUND OF THE INVENTION
It is widely known to monitor the output beam from a laser system to measure various output beam parameters, such as power level, pulse amplitude, pulse width, spatial mode, etc. during laser system operation. Typically, a beam splitter is used to pick off a small portion of the output beam and direct it to one or more detectors.
Different types of detectors are used to measure the different laser beam parameters. Therefore, a single laser system may contain several different types of detectors. Each detector type accurately operates with a particular range of optical input powers. If the power of the reflected beam impinging upon a detector is below that detector's operational range, the measurement will be inaccurate. If the incoming power is above the detector's operational range, the detector can become saturated, such that the measurement will be inaccurate. In more severe cases, the detector could be damaged.
It is known to place neutral density filters in front of detectors to attenuate the intensity of a beam impinging upon the detector. It is also known to move and/or expand the operational range of detectors by designing special detector electronic circuits that automatically adjust the gain of the detector circuit to compensate for different power levels.
Modern laser systems produce output beams having widely varying power levels, pulse widths, and wavelengths. These systems require different detector types to measure the different laser beam parameters, such as average power, pulse energy, pulse width, pulse shape, spatial mode, etc. The various types of detectors used with these lasers must operate over the flail range of operational output powers, pulse widths, and wavelengths.
Using neutral density filters in front of detectors in modem laser systems have several drawbacks. First, for systems with a plurality of detectors, adding these additional optical elements for each detector adds to the complexity and cost of such a system. Second, even though these filters are labeled "neutral density", they are not fully wavelength independent. Therefore, if the output beam is tuned to a different wavelength, the attenuation of the neutral density filter can change. Finally, a neutral density filter cannot maintain proper input power to the detector if the laser power is changed dramatically.
Complex and costly electrical systems have been incorporated into detector devices to change the gain of the detector system to compensate for changes in power level. The changed gain enhances the effective operational range of the detector, allowing it to measure a wider range of power levels. However, these electrical systems are costly for those laser systems containing many detectors. Further, these electrical circuits can only broaden the detector's operational range only so far. Electronic circuits cannot compensate for extremely large changes in input power, pulse width, or wavelength. Nor can they prevent damage to the detector from very high input beam powers.
There is a need for a simplified means for monitoring the different parameters of the output laser beam that is substantially wavelength insensitive. Further, there is a need for a means for monitoring the different parameters of the output laser beam despite very large changes in output power, pulse energy, pulse width, and wavelength.
SUMMARY OF THE INVENTION
The present invention solves the aforementioned problems by providing a device that creates a substantially fixed attenuation over a broad range of wavelengths. The device also provides a plurality of detector beams of different attenuation, whereby different detectors having different operational input power ranges can operate simultaneously to monitor the output beam of a laser system.
The detector system of the present invention includes a refractive element having a pair of opposing spaced-apart faces. The refractive element is transmissive to the laser beam and located such that when the laser beam enters the refractive element through one of the faces, the laser beam is split into at least a primary output beam and a secondary beam at the other of the faces. The primary output beam exits the refractive element through the other of the faces. The secondary beam undergoes multiple internal reflections off of the faces wherein a portion of the secondary beam is transmitted out of the refractive element at each of the reflections to form a plurality of increasingly attenuated output beams having different power intensities from each other. A plurality of detectors are aligned with one or more of the output beams exiting the refractive element for measuring beam characteristics of the output beams which correspond to beam characteristics of the laser beam.
Other objects and features of the present invention will become apparent by a review of the specification, claims and appended figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of the detector system of the present invention.
FIG. 2 is a top plan view of the detector system illustrating a pick-off beam with a non-normal angle of incidence into the refractive element.
FIG. 3 is a top plan view of the refractive element with multiple wedge angles.
FIG. 4 is a top plan view of the refractive element having parallel front and rear faces.
FIG. 5 is a top plan view of the refractive element having a non-planar rear face.
FIG. 6 is a top plan view of the detector system with back-up detectors.
FIG. 7 is a plan view of a composite laser system incorporating the detector system of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is a detector system that produces multiple detector beams of varying intensity. The intensity of the various detector beams is minimally effected by changes in wavelength. The detector apparatus is ideal for monitoring the various laser beam parameters from laser systems that produce output laser beams of widely changing power level, pulse width, and/or wavelength, with minimal space requirements and complexity.
The detector system of the preferred embodiment is illustrated in FIG. 1, and includes a beam splitter 2, a focusing mirror 4, and a refractive element 6.
The beam splitter 2 picks off a small portion of an output beam 8 from a laser system 1 to be monitored. The reflected pick-off beam 10 is directed to a focusing mirror 4.
The focusing mirror 4 focuses the pick-off beam 10 while re-directing it toward the refractive element 6. The focusing mirror 4 is not essential to the present invention if the pick-off beam 10 has a low divergence such that the diameter of any beams produced therefrom incident on optical detectors (to be described later) is smaller than the effective detecting surfaces of those detectors. If focusing is not required, then mirror 4 can be a flat mirror. If the spatial requirements of the detection system do not necessitate folding the pick-off beam 10 to the refractive element 6, then mirror 4 can be eliminated altogether.
The refractive element 6 is a solid optical element in the shape of a wedge. The wedge shaped refractive element 6 can be made of any optically transparent material, such as fused silica. The refractive element 6 has two opposing faces, front face 14 and rear face 16, as well as parallel top and bottom surfaces, 18 and 20 respectively. Rear face 16 forms the wedge angle Θ with a line parallel to front face 14.
The refractive element 6 is positioned such that the pick-off beam 10 enters the refractive element through front face 14 at an angle normal to face 14. A small amount of beam 10 is reflected at surface 14 as beam 10 enters the refractive element 6. The pick-off beam 10 travels through the refractive element 6 and is split at rear face 16 into a primary beam 22 and a secondary beam 24. The primary beam 22 is transmitted out of the refractive element 6. The secondary beam 24 is reflected off of rear face 16 back towards front face 14. The secondary beam 24 continues to undergo multiple internal reflections off of front and rear faces 14 and 16, until it eventually strikes bottom surface 20 of the refractive element 6. If the secondary beam 24 has sufficient energy when it reaches the bottom surface 20, an absorbing plate 26 can be attached to the bottom surface 20 to absorb the energy of the secondary beam 24 to prevent any unwanted thermal effects to the refractive element 6 or bottom surface 20.
At each of the internal reflections of the secondary beam 24, most of the secondary beam 24 is transmitted to form detector beams 28 1 , 28 2 , 28 3 , and 28 4 . Since the secondary beam 24 is attenuated by each of these partial transmissions, each successive detector beam 28 is lower in power than the previous detector beam 28. This results in the generation of a plurality of detector beams 28 1 . . . 28 4 , and a primary beam 22, all having different power intensities. Detectors 30 0 . . . 30 4 are positioned to receive the primary beam 22 and the detector beams 28 1 . . . 28 4 as they exit the refractive element 6.
The production of the plurality of detector beams 28 is accomplished without coated optics or neutral density filters. Therefore, the ratio of detector beam power levels are relatively insensitive to large changes in wavelength. Further, there is only a single optical element used to generate the plurality of detector beams 28, thus minimizing the complexity and cost of the detector system, as well as the space used to create and sample the plurality of detector beams 28.
The path, direction and attenuation of every reflected and transmitted beam are dictated by the wedge angle Θ, the thickness and refractive index of the refractive element, and the angle of incidence α of the pick-off beam 10. These values can be chosen to provide the desired ratio of detector beam intensities and geometric configuration. For example, if the wedge angle Θ is very small, the separation between the detector beams 28 will be small. If the wedge angle Θ is very large, the angles incidence of the secondary beam 24 against faces 14 and 16 will be correspondingly large. If an angle of incidence of the secondary beam 24 becomes too large, undesirable effects might occur. For example, an angle of incidence greater than 15° results in significant different reflectivities for the S and P polarizations. Further, once an angle of incidence reaches the critical angle, total internal reflection will result, and no detector beam will exit the refractive element 6 from such a reflection.
The detector system of the present invention is ideal for several specific types of laser systems. The first example is a laser system that generates a wide range of output powers. Detectors 30 0 . . . 30 4 can all be power detectors having varying operational ranges. As laser power increases, the first detector 30 0 monitoring the primary beam 22 becomes saturated. At that point, the second detector 30 1 is operating within its operational range. As the second detector 30 1 becomes saturated, the third detector 30 2 is operating within its operational range, and so on. Therefore, no matter what the output beam power, one of the detectors 30 0 . . . 30 4 would always be receiving a detector beam 28 having a power level within its operational range.
Another ideal laser system for using the detector system of the present invention is one that requires several different parameters to be measured. In such a system, each detector 30 1 . . . 30 4 is of a different type to measure the different laser beam parameters. For example, detector 30 0 could be a photocell for measuring average power with a relatively high optical input operational range, and detector 30 1 could be a photo-diode for measuring the output beam pulse width with a relatively moderate optical input operational range, and detector 30 2 could be a quad detector for measuring spatial modes with a very low input power operational range, and so on. In such a system, all these parameters can be simultaneously measured by different detectors having widely different optical input operational ranges, without being overly sensitive to wavelength changes.
An additional laser system ideal for using the detector system of the present invention is a laser system that produces several output laser beams with different wavelengths and output powers. An example of such a laser system is a composite laser system, which contains a plurality of cavities each of which having a different gain medium. Each cavity is designed to produce a unique output beam, with its own output power, pulse width, and wavelength. Such a laser system is capable of producing continuous or pulsed output, long pulses or short pulses, high or low power, and all at a wide variety of different power levels and wavelengths. A single detector could be used to measure output power at multiple wavelengths because the attenuation created by the refractive element 6 is substantially independent of wavelength. The detector system of such a composite laser system could also be used to measure the different beam parameters from each of these cavities. The plurality of detector beams 28 produced by the refractive element 6 would have a wide enough range of relative optical powers that detectors of different types having different operational ranges could be used together to accurately monitor the output beam at any operation state.
In an alternate embodiment of the configuration of the preferred embodiment of FIG. 1, the refractive element 6 can be tilted such that the angle of incidence α of the pick-off beam 10 at face 14 can be a non-normal angle, as illustrated in FIG. 2. Beam 29 is present in the previous embodiment, but is coincident with the pick-off beam 10. The incoming light is partially reflected upon entry into the refractive element 6 at the front face 14, to create another detector beam 29. The relative intensities of the detector beams 28, as well as their geometric configuration, can be optimized for a particular application, by modifying the wedge angle Θ, width and refractive index of element 6, as well as the angle of incidence α of the incoming pick-off beam 10.
In yet another embodiment of the present invention, a second wedge angle Φ can be provided by front face 14, as illustrated in FIG. 3. Different combinations of the angle of incidence α, wedge angle Θ, and second wedge angle Φ can be used to create the desired detector beam power levels and geometric configuration for a particular application.
The refractive element 6 could also have parallel faces 14 and 16, as shown in FIG. 4. If the angle of incidence α of the pick-off beam 10 is not normal to front face 14, multiple internal reflections occur to create the plurality of detector beams 28. This embodiment, however, produces less detector beam separation. In order to increase the separation of the detector beams, the thickness of the refractive element 6 and/or the angle of incidence α would have to be increased.
A further embodiment of the present invention is illustrated in FIG. 5. Front and/or rear faces 14 and 16 have non-planar shaped regions to manipulate the primary beam 22, secondary beam 24, and/or the detector beams 28. For example, protrusion 32 totally internally reflects the secondary beam 24, thus allowing for a larger separation between detectors 30 1 and 30 4 . Shaped portion 34 is a rounded surface that acts as a lens to focus the detector beam 28 exiting therethrough. Therefore, by providing non-planar portions of front and rear faces 14 and 16, the beams can be further manipulated.
Another embodiment of the present invention is illustrated in FIG. 6. In this embodiment, a second set of duplicate detectors 44 0 . . . 44 4 is used as a safety back-up to monitor the output laser beam 8. A second pick-off beam 36 is generated by the reflection of the laser's output beam 8 at the rear surface of beam splitter 2. The second pick-off beam 36 produces a second primary beam 38, a second secondary beam 40, and a second set of detector beams 42 for a second set of detectors 44. The second set of detectors 44 is used as a backup, such that if a detector in the first set of detectors 30 0 . . . 30 4 fails, such as a power level detector, the corresponding backup detector 44 measuring power will detect the true output power.
To further optimize the detector beam intensities, optical coatings can be selectively applied to front and rear faces 14 and 16 to provide the desired ratio of power levels among the various detector beams.
A composite laser system using the refractive element of the present invention which is being developed for commercial release is illustrated in FIG. 7. This composite laser system includes three laser cavities 50, 52, and 54, an external doubling crystal 56, and a combining means 58 for combining the separate beams from the cavities 50/52/54 into a single laser system output beam 60. Cavity 50 is a Q-switched Nd:Yag laser cavity that produces 1064 nm light at 10 Hz with pulse energies of 400 mJ and pulse widths of 5 ns. Cavity 52 is an intra-cavity doubled Nd:Yag laser cavity using a KTP doubling crystal that produces 532 nm light at 6 Hz with pulse energies of about 0.2-1.75 J and pulse widths of 2-10 ms. A laser formed in this manner is described in greater detail in co-pending application Ser. No. 08/369,465, filed Jan. 6, 1995, now U.S. Pat. No. 5,558,667, assigned to the same assignee as herein. Cavity 54 is a Q-switched Alexandrite laser cavity that produces 755 nm light at 10 Hz with pulse energies of 500 mJ and pulse widths of 60 ns. A selection device 55 is mounted to intercept the output of the cavity 50 and alternately direct the output beam directly to the combining means, or to the external doubling crystal. When the output beam from cavity 50 is directed to the external doubling crystal 56, the crystal produces 532 nm light at 10 Hz with pulse energies of 200 mJ and pulse widths of 4 ns. The crystal output, combined with the residual fundamental output from cavity 50, can be separated before entering combining means 58, or by combining means 58. Therefore, this composite laser system is capable of four different possible unique output beams. These unique beams are combined by the combining means 58 to form a single output beam 60. The combining means 58 can be rotating mirrors or a prism, that capture a given unique beam and reflect that beam out as the output beam 60.
The output beam 60 passes through beam splitter 62 which reflects part of the output beam (about 2%) at each surface, to create two pick-off beams 64 and 66 in the same manner as shown in FIG. 6. The beam splitter 62 is slightly wedged, to better separate pick-off beams 64 and 66. Focusing mirror 68, having a focal length of 125 mm focuses the pick-off beams 64/66 and directs them to refractive element 70. Refractive element 70 is a fused silica wedge having a 4° wedge angle. Pick-off beams 64/66 strike the refractive element surface at an angle of incidence of 5°, producing reflection beams 71, secondary beams 80, primary beams 73, and detector beams 76 and 78. Silicon photo-diode detectors 72/74 (from Centronic Inc., part no. OSD15-0) are aligned with the detector beams 76 and 78 respectively, which exit the refractive element 70 after the first and second internal reflections of secondary beams 80. The detectors 74 measure the output power of the composite laser system when the intra-cavity doubled cavity 52 is in operation, and detectors 72 measure the output power of the composite laser system when the Nd:Yag cavity 50 (either fundamental or doubled output) or the Alexandrite cavity 54 is in operation. Diffusers can be placed in front of the detectors, to eliminate the effects of movement in the detector beams and to further attenuate the detector beams.
The relative intensities of the different beams depend upon the different angles of incidence, the refractive index (for each wavelength), and the state of the polarization. Since the wavelength of the beams varies only between 532 to 1064 nm, and the angles of incidence are relatively low (below 20° thus negating significant polarization effects), it can be roughly estimated that at each reflection, about 4% of each beam is reflected and 96% of each beam is transmitted. Therefore, if I is the intensity of pick-off beams 64/66 as they enter the refractive element 70, then the remaining beams have the following approximate intensities:
______________________________________Beams Intensity as a Percentage of I______________________________________71 4%73 92%78 3.7%76 0.15%______________________________________
The above embodiment provides two different attenuated detector beams 78/76 having 3.7% and 0.15% of the intensity of pick off beams 64/66, to allow detectors 72/74 to effectively monitor the output beam at multiple wavelengths (1064 nm, 532 nm, and 755 nm) whereby the attenuation of the different wavelengths is substantially the same.
It is to be understood that the present invention is not limited to the embodiments described above and illustrated herein, but encompasses any and all variations falling within the scope of the appended claims. For example, the number of detector beams and detectors can vary from the numbers illustrated in the figures. Further, the laser beam 8 can be passed directly through the refractive element 6, without the aid of a beam splitter or focusing mirror. | A detector system for providing a plurality of output beams for monitoring the output beam of a laser system. The detector system includes a refractive element having a pair of opposing spaced-apart faces. The laser beam enters the refractive element where it undergoes multiple internal reflections off of the faces. A portion of the beam is transmitted out of the refractive element at each of the reflections to form a plurality of increasingly attenuated output beams having different power intensities from each other. A plurality of detectors are positioned for measuring the different beam characteristics of the plurality of attenuated output beams, which correspond to the beam characteristics of the laser output beam. | 7 |
[0001] This application claims priority from previously regularly filed US Provisional Application filed on Oct. 17, 2000 under Application No.: 60/240,847, by Harold Meredith having the title METAL CONSTRUCTION PANEL.
FIELD OF THE INVENTION
[0002] The invention relates to pre-engineered metal building systems and more specifically to an improved metal construction panel for use in forming the exterior wall of buildings.
BACKGROUND OF THE INVENTION
[0003] Currently in North America and Canada, the traditional method for building residential and some commercial buildings is wood framing, on top of a concrete foundation, after which the framing is either clad with brick or siding. With the disappearance of many of the best forests in North America, the lack of good lumber has driven up wood prices and therefore constructing homes using conventional wood framing technics is slowly becoming prohibitably too expensive.
[0004] A number of metal building systems are on the market including replacement of existing 2×4 and 2×6 wood studding and members with metal counter parts which are installed in a similar manner as the wood they are replacing. The disadvantage of this system is that the traditional framing and cladding process must occur, thereby there is little savings in regard to labour costs.
[0005] A number of other inventions have tried to address this problem by providing for a metal panel which provides both structural strength as well as exterior cladding for a building. Such building panels and methods of construction are described in U.S. Pat. No. 1,883,141 by Walters issued Oct. 18, 1932 titled Building Construction.
[0006] U.S. Pat. No. 2,023,814 titled: Metal Building Construction, issued on Dec. 10, 1935 to Samuel Lindsay and finally U.S. Pat. No. 3,568,388 titled Building Panel, filed by Charles T. Flachfbarth and Robert L. Parsons issued on Mar. 9, 1971. These patents describe building construction methods using a metal panel which serves both as a structural panel as well as an exterior architectural finished surface. By using these panels in one step, both framing and cladding of the house is completed. The advantage of the systems that they describe are the potentially reduced labour costs by eliminating one step in the building construction phase and in addition to that the improved strength of the house as well as the fire resistance and other safety features not found in wood constructed homes.
[0007] The disadvantage with these building systems is that they fail to address the problems of sealing off the joints in between the panels, thereby preventing water from seeping into the house due to capillary action. Secondly, the lack of flexibility in regard to choosing the exterior look. The user of such panels cannot choose alternate exterior cladding looks other than the one provided by the panels themselves.
SUMMARY OF THE INVENTION
[0008] The present invention an elongated metal construction panel for use in forming a portion of the vertical walls of a building structure by being fastened to an identical adjacent panel, the metal construction panel comprises:
[0009] (a) a front portion co-extensive with the length of the panel;
[0010] (b) end plates co-extensive with the length of the panel disposed substantially normal to said front portion and extending from distal ends of said front portion, said end plates defining the depth of said panel;
[0011] (c) flanges co-extensive with the length of the panel and extending inwardly from distal ends of said end plate, wherein said flanges are spaced from and parallel to said front portion; and
[0012] (d) wherein said end plates include end troughs co-extensive with the length of the panel such that when metal construction panels are placed adjacent each other by bringing into contact said end plates, said end troughs form a bonding channel adapted and sized for pouring bonding agents therein thereby securely fastening adjacent panels together and also waterproofing the joint between said end plates.
[0013] Preferably wherein said end troughs including a fluted section having a U shaped profile being co-extensive with the length of the panel.
[0014] Preferably wherein the width of said front portion is at least 3 times the depth of said end plate.
[0015] Preferably the width of said front portion is preferably 4 times the depth of said end plate.
[0016] Preferably wherein the depth of said end plate being at least 3½ inches.
[0017] Preferably wherein the front portion includes female dovetail grooves co-extensive with the length of the panel and adapted to co-operate with an attachment clip for fastening articles to said attachment clip.
[0018] Preferably wherein said dovetail grooves define fluted surfaces disposed at an angle theta less than 90°.
[0019] Preferably wherein said angle theta is preferably 87°.
[0020] Preferably wherein said attachment clip defines male dovetail tabs cooperating with said female dovetail grooves to hold said clip within said dovetail grooves, whereby said tabs are joined together in spaced apart relationship by a joining member.
[0021] Preferably wherein said tabs are resiliently biased such that said tabs are compressed for placing said tabs within said female dovetail grooves and upon release said resiliently biased tabs hold said attachment clip within said female dovetail grooves.
[0022] Preferably wherein said attachment clip further comprises wings extending from said tabs and oriented substantially parallel and adjacent to said front portion for securely fastening said clip to said panel.
[0023] Preferably wherein said attachment clip further comprises an attachment lip rigidly connected to said joining member for fastening articles thereto.
[0024] Preferably wherein said attachment lip is adapted for fastening vinyl siding thereto.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention will now be described by way of example only, with references to the followings drawings in which:
[0026] [0026]FIG. 1 is a schematic top perspective view of the metal construction panel.
[0027] [0027]FIG. 2 is a partial cut away schematic showing the installation and joining of two metal construction panels together with drywall.
[0028] [0028]FIG. 3 is a top cross sectional view of two metal construction panels joined together showing a clip attached to one panel.
[0029] [0029]FIG. 4 is a schematic perspective assembly view of metal construction panels upon a foundation illustrating how the metal construction panels would be joined together.
[0030] [0030]FIG. 5 is a front perspective view of an attachment clip for use with the metal construction panel.
[0031] [0031]FIG. 6 is a view of the metal plank which would be bent and folded to produce the attachment clip and also showing how the attachment clip cooperates with the metal construction panel.
[0032] [0032]FIG. 7 is a top plan view of the attachment clip.
[0033] [0033]FIG. 8 is a cross-sectional schematic view of two metal construction panels joined together showing how a strengthening member can be used at such a junction.
[0034] [0034]FIG. 9 is a schematic cross-section view of metal construction panels joined together at a corner showing the use and the insertion of a strengthening member at the corner section as well as an attachment flange for fastening wall boards onto the interior corner portion.
[0035] [0035]FIG. 10 is a schematic cross-section view of an alternate corner arrangement showing two metal construction panels intersecting at a corner post.
[0036] [0036]FIG. 11 is a schematic prospective view showing a tool installing an attachment clip into a dove tail groove of a metal construction panel.
[0037] [0037]FIG. 12 is a top cross sectional view of two metal construction panels of the presently preferred type showing the modified flange arrangement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0038] Referring first of all to FIG. 1 which schematically shows a metal construction panel showing generally as 20 having a front 22 , end plates 24 , flanges 26 , end troughs 28 , and dovetail grooves 30 . Front 22 of panel 20 has length 102 , width 104 and end plates 24 have depth 106 . The panel is oriented vertically along longitudinal axis 90 . Front 22 has front first end 92 and front second end 94 . End plates 24 include end plate distal end 96 .
[0039] Referring now to FIG. 2 which schematically illustrates the joining of two end plates 24 of metal construction panels 20 . Metal construction panels 20 are joined together when end plates 24 come in contact with each other, such that end troughs 28 form a bonding channel 32 which is a rectangular tubular section running longitudinally along the length of metal construction panel 20 . The tubular section can take on any number of shapes other than shown here. Metal construction panels 20 can be mechanically fastened together using fastener attachments 32 which could for example be a nut and bolt arrangement mechanically connecting end plates 24 together. Preferably, however in order to seal off the joint formed by joining end plates 24 together, a bonding material is poured into bonding channel 32 thereby sealing off the groove or joint formed between end plates 24 therefore preventing water from entering from front 22 of metal construction panels 20 via capillary action and into the interior of the home.
[0040] From FIG. 2, one can see that front 22 forms the exterior architectural portion of the home, whereas flanges 26 serve as fastening attachments for screwing or nailing wallboard 40 onto flanges 26 . Wallboard 40 can be the conventional drywall sheets which are used in conventional home construction now and/or can be another type of interior surfacing which is suitable. Panel 20 preferably is fabricated from sheet steel or aluminum and is preferably fabricated using the roll forming process.
[0041] Referring now to FIG. 3 showing in cross section two metal construction panels 20 joined together, and in particular dovetail grooves 30 are shown having an angle theta 42 of approximately 87 degrees. Further attachment clip 38 is shown in situ in dovetail groove 30 indicating how attachment clip 38 is mounted to a metal construction panel 20 . In this view, also one can see how bonding channel 32 is formed by adjacent end troughs 28 when end plates 24 are brought together.
[0042] Referring now to FIG. 4, a number of metal construction panels 20 are shown in schematic fashion mounted together onto a foundation 52 . Typically on top of a concrete foundation 52 , a foundation channel 50 would be mounted into place and there upon metal construction panels 20 would be fastened such that they extend vertically upward from foundation 52 , along longitudinal axis 90 . Those skilled in the art will see that metal construction panel 20 serves not only as a structural wall member but also as an exterior architectural panel for the building construction. Metal construction panels 20 are joined at end plates 24 either adhesively by pouring adhesive into bonding channel 32 and/or including mechanical fastening attachments 34 shown in FIG. 2. It is apparent that front 22 of metal construction panels 20 is disposed outwardly creating the exterior cladding of the building. In addition, dovetail grooves 30 extend vertically along metal construction panels 20 for accommodating attachment clips 38 as will be explained here below. Typically once metal construction panels 20 have been erected onto foundation channel 50 , a top plate 54 is mounted and fastened to the top portion of metal construction panels 20 which can be used for subsequent erection of the roof truss sections or other roof construction.
[0043] Attachment Clip
[0044] Referring now to FIGS. 5, 6 and 7 which schematically shows the details of attachment clip 38 shown in situ in FIG. 3, attachment clip 38 includes joining member 61 , right tab 60 , left tab 62 , right wing 68 , left wing 70 , apertures 66 , and attachment lip 64 . In practice, attachment clip 38 would be made from a sheet of steel and the metal blank prior to bending is shown as clip blank 74 in FIG. 6. The dashed lines in FIG. 6 represent the bend lines in order to fabricate attachment clip 38 into the finished product as shown in FIG. 5. In other words clip bank 74 is bent along the dashed lines to produce attachment clip 38 . Attachment clip 38 is so designed such that right tab 60 and left tab 62 can be resiliently flexed to fit and cooperate with dovetail grooves 30 of metal construction panels 20 .
[0045] In use dovetail grooves 30 and metal construction panels 20 have an angle theta 42 of approximately 87 degrees, whereas right tab 60 makes an angle alpha 72 of approximately 85 degrees. Attachment clip 38 is installed into dovetail groove 30 by deflecting or compressing right tab 60 and left tab 62 such that they fit into dovetail grooves 30 of metal construction panel 20 . Attachment clip 38 as shown in FIG. 3 is held in dovetail groove 30 by the biasing force imparted by right tab 60 and left tab 62 onto the inner surfaces of the dovetail grooves 30 of metal construction panel 20 . In addition, apertures 66 can be used to install fastening screws for rigidly attaching and screwing attachment clip 38 to the metal construction panel 20 .
[0046] Attachment lip 64 extends outwardly from front 22 of metal construction panel 20 and is used for attaching various cladding materials should the user of metal construction panel 20 wish to have an alternative exterior look than the one provided by front 22 of metal construction panel. In this manner by placing numerous attachment clips 38 onto dovetail grooves 30 , one can clad the entire exterior surface or the front 22 of metal construction panel 20 and provide for any particular look or architectural appearance the end user desires. For example, brick face, siding, vinyl siding, wood siding, panelling, stucco or any other currently known architectural type finishes can be applied to the front 22 of metal construction panels 20 .
[0047] Those skilled in the art will appreciate the advantages of the current system namely, one could potentially avoid having to have separate framing and architectural finishing surfaces applied to the exterior of the home, but yet retain the flexibility of adding a particularly architectural surface to the exterior of the home, depending on the end use requirement. Furthermore, using metal construction panels 20 , a totally waterproof construction is used due to filling bonding channels 32 with a bonding agent, thereby preventing capillary action of water penetrating through the connection seam between adjacent metal construction panels 20 .
[0048] The bonding agents can be commercially available exterior caulking compounds including silicone, epoxy or polyester based compounds.
[0049] Referring now to FIG. 11, which in schematic fashion shows the installation of an attachment clip 38 being installed into a dove tail groove 30 . Installation tool 190 as shown in FIG. 11 having tips 192 which are received in apertures 66 of left and right wing 70 and 68 of attachment clip 38 . Installation tool 190 is a hand held tool in which handles 198 are compressed in a direction as shown by arrows 194 thereby urging together right and left tab 60 and 62 of attachment clip 38 . Right and left tabs of attachment clip 38 are resiliently bias such that by compressing right and left tab 60 and 62 , the attachment clip 38 can be urged into dove tail grooves 30 such that right and left wing 68 and 70 lie substantially parallel and adjacent to the back portion of dove tail grooves 30 . By removing tips 192 of installation tool 190 from attachment clip 38 , leaves attachment clip 138 in position in dove tail groove 30 . By reversing the procedure described above the attachment clip 38 can be removed from dove tail groove 30 . Note that apertures 66 therefore have two functions, first of all for installing and uninstalling attachment clip 38 from dove tail groove 30 by cooperating with tips 192 of an installation tool 190 and secondly for mechanically fastening attachment clip 38 to metal construction panel 20 by placing screws through apertures 66 into the back of dove tail groove 30 thereby permanently affixing attachment clip 38 to metal construction panel 20 .
[0050] Strengthening Member
[0051] Referring now to FIGS. 8 and 9, showing metal construction panels 20 attached together and a strengthening member 110 used to provide additional compressive strength as well as stiffening to the structure for providing enough structural strength for the building to support the roof and other structural weight and also to provide wind and earthquake resistance by the addition of strengthening member 110 .
[0052] Looking to FIG. 8 which shows in cross-section the profile of strengthening member 110 ; strengthening member 110 has an end trough section 128 , end plate portions 124 and end flange sections 127 and is designed to nest inside and conform with the contour of end plate 24 of metal construction panel 20 . Referring now to FIG. 9, strengthening member 110 is shown in situ at a corner section of a metal construction panel 20 and is nested and adjacent to the end plate 24 of construction panel 20 . In addition to this the metal construction panel 20 along with the strengthening members 110 are fastened with anchors 112 into concrete at the base and with mechanical fasteners as shown into the metal construction panel 20 .
[0053] [0053]FIG. 9 in particular shows a corner construction possibility by using two metal construction panels 20 to form said corner. The reader will note that no custom section or special section is required in order to form a corner. In order to attach wall board 40 onto the flanges 26 of metal construction panel 20 in a corner as depicted, an attachment flange 130 is required in order to fasten the wall boards 40 together.
[0054] Strengthening members 110 are co-extensive with the entire length of metal construction panel 20 and can be placed periodically along the walls formed by metal construction panels 20 . For example if extra strength is required, strengthening members 110 can be placed at every end plate 24 of metal construction panel 20 found in a wall. Strengthening members 110 are especially used where the gauge or thickness of the material used to form metal construction panel 20 is too thin to support the structural weight of the building and/or to provide enough stiffness or enough wind resistance. By the use of strengthening members 110 , one can form metal construction panel 20 out of a thinner gauge material and yet obtain enough structural strength and stiffness by including additional strengthening members 110 as required. This reduces the overall costs of manufacturing metal constructions panels and allows one to produce the lightest possible weight panel for a given application.
[0055] Referring now to FIG. 10 which shows a heavy duty corner construction using a corner post 150 which is a tubular metal corner post construction. As shown in the previous Figures, anchors 112 are used to connect metal construction panel 20 to corner post 150 .
[0056] Presently Preferred Metal Construction Panel
[0057] [0057]FIG. 12 shows a presently preferred embodiment of metal construction panel 220 . In most respects metal construction panel 220 is analogous to metal construction panel 20 in that the front face 222 includes dove tail grooves 30 and also includes end plates 24 having end trough 28 forming a bonding channel 32 between two metal construction panels 220 forming a joint 31 . These items remain unchanged and identical to the previously described metal construction panel 20 as shown in FIG. 1. The modification to metal construction panel 220 is the modified flange 226 which includes dimples 227 as shown in FIG. 12. The function of Flange 226 is for mounting wall board and/or other interior finishing materials onto flange 226 as shown in FIG. 12. Wall board 40 as shown in FIG. 12 can either be nailed and/or screwed into any portion of flange 226 in order securely fasten wall board 40 onto flange 226 . By providing dimples 227 , the wall board 40 makes contact with flange 226 at contact points 229 as shown in FIG. 12. This configuration provides for additional structural strength by increasing the stiffness of metal construction panel 220 by introducing dimples 227 which run along the entire length 102 of metal construction panel 220 and also provide additional compressive strength due to the increased stiffness and cross sectional area of the load bearing member.
[0058] The other advantage provided by dimples 227 on flanges 226 is the reduced heat conduction from the front face 222 of metal construction panel through end plate 24 and out through flanges 226 and into the interior of the building through wall board 40 . The amount of heat that can be conducted through metal construction panel 220 and into wall board 40 is significantly reduced due to the reduction in the amount of contact surface of flange 226 with wall board 40 . Contact between wall board 40 and 226 is limited to contact points 229 as shown in FIG. 12. Dimples 227 can be of different geometries than shown in FIG. 12. As shown in FIG. 12, dimple 227 are crescent shaped or half moons or half circles in shape, however, they also may be squared off, triangular, V-shaped, and/or any other shape which minimizes the contact between wall board 40 and flange 226 .
[0059] It should be apparent to persons skilled in the arts that various modifications and adaptation of this structure described above are possible without departure from the spirit of the invention the scope of which defined in the appended claim. | The present invention an elongated metal construction panel for use in forming a portion of the vertical walls of a building structure by being fastened to an identical adjacent panel, the metal construction panel comprising a front portion co-extensive with the length of the panel; end plates co-extensive with the length of the panel disposed substantially normal to said front portion and extending from distal ends of said front portion, said end plates defining the depth of said panel; flanges co-extensive with the length of the panel and extending inwardly from distal ends of said end plate, wherein said flanges are spaced from and parallel to said front portion; and wherein said end plates include end troughs co-extensive with the length of the panel such that when metal construction panels are placed adjacent each other by bringing into contact said end plates, said end troughs form a bonding channel adapted and sized for pouring bonding agents therein thereby securely fastening adjacent panels together and also waterproofing the joint between said end plates. | 4 |
BACKGROUND AND SUMMARY
[0001] The invention relates to filters, including air cleaners.
[0002] The invention arose during continuing development efforts directed toward filter assemblies providing more efficient use of space and better performance, including smaller package size and more flexibility in package geometry. The present system provides more filter media area in a given volume.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is perspective cut-away view of a filter constructed in accordance with the invention.
[0004] FIG. 2 is a perspective view of a portion of the assembly of FIG. 1 .
[0005] FIG. 3 is a perspective view of the housing of the assembly of FIG. 1 .
[0006] FIG. 4 is like FIG. 1 and shows a further embodiment.
DETAILED DESCRIPTION
[0007] FIGS. 1-3 show a filter 10 including a housing 12 having an inlet 14 and an outlet 16 . A first flow passage 18 is provided through the housing from inlet 14 to outlet 16 , and includes a first filter element 20 filtering fluid flowing along first flow passage 18 . A second flow passage 22 is provided through the housing from inlet 14 to outlet 16 , and includes a second filter element 24 filtering fluid flowing along second flow passage 22 . First and second flow passages 18 and 22 are in parallel with each other such that incoming fluid flow at inlet 14 is split into first and second parallel flow paths in first and second flow passages 18 and 22 , respectively, and flows through first and second filter elements 20 and 24 , respectively, and re-joins at outlet 16 . First and second flow passages 18 and 22 through respective first and second filter elements 20 and 24 are independent of each other.
[0008] Housing 12 includes an internal dividing wall 26 separating first and second flow passages 18 and 22 such that fluid in first flow passage 18 flows through first filter element 20 to the exclusion of and bypassing second filter element 24 , and such that fluid in second flow passage 22 flows through second filter element 24 to the exclusion of and bypassing first filter element 20 . First filter element 20 has an upstream face 28 receiving incoming fluid along first flow passage 18 from inlet 14 . First filter element 20 has a downstream face 30 delivering filtered fluid along first flow passage 18 to outlet 16 . Second filter element 24 has an upstream face 32 receiving incoming fluid along second flow passage 22 from inlet 14 . Second filter element 24 has a downstream face 34 delivering filtered fluid along second flow passage 22 to outlet 16 . Internal dividing wall 26 has a first surface 36 facing downstream face 30 of first filter element 20 . Internal dividing wall 26 has a second surface 38 facing oppositely to first surface 36 and facing upstream face 32 of second filter element. Housing 12 has a first sidewall 40 defining a first plenum 42 between first sidewall 40 and upstream face 28 of first filter element 20 . Internal dividing wall 26 has the noted first surface 36 defining a second plenum 44 between surface 36 of internal dividing wall 26 and downstream face 30 of first filter element 20 . Internal dividing wall 26 has the noted second surface 38 defining a third plenum 46 between surface 38 of internal dividing wall 26 and upstream face 32 of second filter element 24 . Housing 12 has a second sidewall 48 defining a fourth plenum 50 between housing sidewall 48 and downstream face 34 of second filter element 24 .
[0009] In the preferred embodiment, first and second sidewalls 40 and 48 of the housing are spaced by first filter element 20 , internal dividing wall 26 , and second filter element 24 respectively in serial spatial alignment therewith. Further in the preferred embodiment, housing sidewalls 40 and 48 are spaced by first plenum 42 , first filter element 20 , second plenum 44 , internal dividing wall 26 , third plenum 46 , second filter element 24 , and fourth plenum 50 respectively in serial spatial alignment therewith. First and third plenums 42 and 46 communicate with each other at inlet 14 . Second and fourth plenums 44 and 50 communicate with each other at outlet 16 .
[0010] First and second filter elements 20 and 24 are spaced from each other by a gap 52 . Internal dividing wall 26 is a diagonal wall which diagonally spans gap 52 and defines an upstream triangular shaped plenum 46 having a closed corner end 54 at upstream face 32 of second filter element 24 , and having an open end 56 communicating with inlet 14 . Diagonal wall 26 also defines a downstream triangular shaped plenum 44 having a closed corner end 58 at downstream face 30 of first filter element 20 , and having an open end 60 communicating with outlet 16 . In the preferred embodiment, diagonal wall 26 has a non-rectilinear wave shape providing increased entrance area at upstream open end 56 of triangular shaped plenum 46 and reduced area at closed corner end 54 of triangular shaped plenum 46 , and providing increased exit area at downstream open end 60 of triangular shaped plenum 44 and reduced area at closed corner end 58 of triangular shaped plenum 44 .
[0011] A spacer 62 supports first and second filter elements 20 and 24 and maintains gap 52 therebetween. Spacer 62 has first and second spacer walls 64 and 66 extending transversely (up-down in FIGS. 1, 2 ) across gap 52 , and extending longitudinally (left-right in FIGS. 1, 2 ) between open ends 56 and 60 of upstream and downstream triangular shaped plenums 46 and 44 . Spacer walls 64 and 66 are laterally spaced from each other by diagonal wall 26 therebetween. The spacer walls have upstream ends communicating with inlet 14 , and have downstream ends communicating with outlet 16 . Spacer walls 64 and 66 extend longitudinally (left-right in FIGS. 1, 2 ) between such upstream and downstream ends. The upstream ends of spacer walls 64 and 66 are laterally spaced by open end 56 of upstream triangular shaped plenum 46 therebetween. The downstream ends of spacer walls 64 and 66 are laterally spaced by open end 60 of downstream triangular shaped plenum 44 therebetween. Diagonal wall 26 has an upstream end 68 spanning laterally between the upstream ends of spacer walls 64 and 66 . Diagonal wall 26 has a downstream end 70 spanning laterally between the downstream ends of spacer walls 64 and 66 . Spacer 62 has an upstream bridging portion 72 extending laterally between the upstream ends of spacer walls 64 and 66 and transversely spaced from upstream end 68 of diagonal wall 26 by open end 56 of upstream triangular shaped plenum 46 therebetween. Spacer 62 has a downstream bridging portion 74 extending laterally between the downstream ends of spacer walls 64 and 66 and spaced transversely from downstream end 70 of diagonal wall 26 by open end 60 of downstream triangular shaped plenum 44 therebetween. The spacer walls may be solid, or may be provided by a plurality of transversely extending ribs 65 , 67 , respectively, as shown.
[0012] A gasket 76 , FIG. 2 , seals first and second filter elements 20 and 24 and spacer 62 to housing 12 . Gasket 76 has an upstream segment 78 extending along upstream bridging portion 72 of spacer 62 , a downstream segment 80 extending along downstream bridging portion 74 of spacer 62 , and a pair of laterally spaced diagonal side segments 82 and 84 extending diagonally along spacer walls 64 and 66 diagonally oppositely to the diagonal extension of diagonal wall 26 . In FIGS. 1 and 2 , diagonal side segments 82 and 84 of the gasket extend diagonally from upper right to lower left, whereas diagonal wall 26 extends diagonally from lower right to upper left. Housing 12 is provided by a pair of shrouds 86 and 88 , FIGS. 1, 3 removably mated to each other along an interface 90 coincident with gasket 76 including diagonal side segments 82 and 84 of the gasket. Inlet 14 is in shroud housing section 86 . Outlet 16 is in shroud housing section 88 . The shrouds are removably mounted to each other, for example, by hinges or clips such as 92 at one end, and clamps such as 94 at the other end. The shrouds preferably pinch and compress gasket 76 therebetween along the entire perimeter thereof including gasket segments 78 , 80 , 82 , 84 .
[0013] The above principles may be applied to multiple flow filter systems wherein the filter housing may have multiple flow passages including the noted first and second flow passages and one or more additional flow passages therethrough. FIG. 4 shows a further embodiment and uses like reference numerals from above where appropriate to facilitate understanding. A third flow passage 100 is provided through housing 12 from inlet 14 to outlet 16 , and includes a third filter element 102 filtering fluid flowing along third flow passage 100 . First and second and third flow passages 18 and 22 and 100 are in parallel with each other such that incoming fluid flow at inlet 14 is split into first and second and third parallel flow paths in first and second and third flow passages 18 and 22 and 100 , respectively, and flows through first and second and third filter elements 20 and 24 and 102 , respectively, and re-joins at outlet 16 . First and second and third flow passages 18 and 22 and 100 through respective first and second and third filter elements 20 and 24 and 102 are independent of each other. The housing has a second internal dividing wall 104 separating second and third flow passages 22 and 100 . Fluid in first flow passage 18 flows through first filter element 20 to the exclusion of and bypassing second and third filter elements 24 and 102 . Fluid in second flow passage 22 flows through second filter element 24 to the exclusion of and bypassing and first and third filter elements 20 and 102 . Fluid in third flow passage 100 flows through third filter element 102 to the exclusion of and bypassing first and second filter elements 20 and 24 . Third filter element 102 has an upstream face 106 receiving incoming fluid along third flow passage 100 from inlet 14 , and a downstream face 108 delivering filtered fluid along third flow passage 100 to outlet 16 . Second internal dividing wall 104 has a first surface 110 facing downstream face 34 of second filter element 24 , and a second surface 112 facing oppositely to first surface 110 and facing upstream face 106 of third filter element 102 . Internal dividing wall 104 has the noted first surface 110 defining a plenum 114 between surface 110 and downstream face 34 of second filter element 24 . Internal dividing wall 104 has the noted second surface 112 defining a plenum 116 between surface 112 and upstream face 106 of third filter element 102 . Housing sidewalls 40 and 48 in FIG. 4 are spaced by first filter element 20 , first internal dividing wall 26 , second filter element 24 , second internal dividing wall 104 , and third filter element 102 respectively in serial spatial alignment therebetween. More specifically in FIG. 4 , sidewalls 40 and 48 are spaced by plenum 42 , first filter element 20 , plenum 44 , first internal dividing wall 26 , plenum 46 , second filter element 24 , plenum 114 , second internal dividing wall 104 , plenum 116 , third filter element 102 , and plenum 50 respectively in serial spatial alignment therebetween. Plenums 42 and 46 and 116 communicate with each other and with inlet 14 . Plenums 44 and 114 and 50 communicate with each other and with outlet 16 . Second and third filter elements 24 and 102 are spaced from each other by a gap 118 , by a second spacer 62 a comparable to spacer 62 . Internal dividing wall 104 is a diagonal wall which diagonally spans gap 118 and defines an upstream triangular shaped plenum 116 having a closed corner end 120 at upstream face 106 of third filter element 102 , and having an open end 122 communicating with inlet 14 . Diagonal wall 104 also defines a downstream triangular shaped plenum 114 having a closed corner end 124 at downstream face 34 of second filter element 24 , and having an open end 126 communicating with outlet 16 . Diagonal wall 104 preferably has a non-rectilinear wave shape providing increased entrance area at upstream open end 122 of triangular shaped plenum 116 and reduced area at closed corner end 120 of triangular shaped plenum 116 , and providing increased exit area at downstream open end 126 of triangular shaped plenum 114 and reduced area at closed corner end 124 of triangular shaped plenum 114 . Fourth, fifth, and so on, multiple filter elements and flow passages may be provided in accordance with the above teachings.
[0014] It is recognized that various equivalents, alternatives and modifications are possible within the scope of the appended claims. | A filter includes a housing with multiple flow passages and filter elements, including at least first and second flow passages therethrough including respective first and second filter elements in parallel. Respective internal dividing walls separate flow passages in space saving relation. | 1 |
TECHNICAL FIELD
The present invention relates to a rotary electric machine (rotating electrical machine) having a wiring arrangement that makes it possible to reduce the size of the rotary electric machine in a radial direction.
BACKGROUND ART
According to Japanese Laid-Open Patent Publication No. 2009-017667 (hereinafter referred to as “JP 2009-017667 A”), three feeder terminals 63 of a motor 1 are disposed radially outward of a stator holder 11 (see FIGS. 2 and 3). An electric power line, which connects the motor 1 to an inverter and a non-illustrated electric storage device, is connected to each of the feeder terminals 63.
SUMMARY OF INVENTION
If the feeder terminals 63 are disposed radially outward of the stator holder 11, as disclosed in JP 2009-017667 A, the radial dimension of the motor 1 is increased, because the feeder terminals 63 must be connected to the electric power lines radially outward of the stator holder 11.
The present invention has been made in view of the aforementioned problem. An object of the present invention is to provide a rotary electric machine that can be reduced in size in a radial direction.
According to the present invention, a rotary electric machine is characterized by a stator with coils wound thereon, a housing that houses the stator therein, and a junction conductor electrically joining the coils and external electric power lines, which are disposed outside of the housing, to each other. The junction conductor includes coil joints connected to the coils on one side of a rotational shaft of the rotary electric machine radially outward of the coils, electric power line joints connected to the external electric power lines on another side of the rotational shaft, and a junction extending in an axial direction of the rotational shaft and coupling the coil joints and the electric power line joints to each other. Further, at least a portion of the electric power line joints is positioned radially inward of an outer circumferential surface of the stator with respect to the rotary electric machine.
According to the present invention, the electric power line joints are shifted from the stator in the axial direction, and are positioned radially inward of the outer circumferential surface of the stator. Therefore, rather than being positioned radially outward of the outer circumferential surface of the stator, the dimension of the rotary electric machine along the radial direction thereof is reduced by the extent to which the external electric power line joints are positioned radially inward of the outer circumferential surface of the stator.
The junction conductor may include coil-side conductors including the coil joints, and electric power line-side conductors including the electric power line joints, the electric power line-side conductors being separate from the coil-side conductors. The coil-side conductors and the electric power line-side conductors are connected to intermediate joints, which are positioned radially outward of the outer circumferential surface of the stator.
When the stator is assembled in an axial direction on the housing, if a portion of the electric power line joints is positioned radially inward of the outer circumferential surface of the stator, it may be difficult to work from the axial direction on the external electric power line joints. According to the above structure, however, the electric power line-side conductors and the external electric power lines may be connected together mutually, thereby making up the external electric power line joints. Then, the coil-side conductors and the electric power line-side conductors may be connected in order to make up the intermediate joints, so that the coils and the electric power lines can be connected to each other. Consequently, it is easier to assemble the junction conductor.
The coil joints and the intermediate joints may have respective portions, which are staggered mutually on circumferential planes having the same radius as viewed axially from the rotational shaft. Such a configuration prevents the rotary electric machine from becoming increased in dimension along the radial directions. In addition, since the intermediate joints can be worked on along the axial direction, it is easier to assemble the coil-side conductors.
The coils may have coil ends that project radially outward with respect to the rotary electric machine, and the coil joints may be made up of the junction conductor and the coil ends, which are connected to each other. The junction conductor may include bent plate-like members. The bent plate-like members may further include first planar portions including the coil joints, the first planar portions being disposed along radial and circumferential directions of the rotary electric machine, and second planar portions coupled to the first planar portions, the second planar portions extending along axial and radial directions radially outward of the outer circumferential surface of the stator.
With the above arrangement, each of the first planar portions and the second planar portions lies perpendicular to the outer circumferential surface of the stator. Therefore, the plate-like members can easily be spaced from the outer circumferential surface of the stator, and it is possible to prevent degradation of the insulation between the plate-like members (junction conductor) and the outer circumferential surface of the stator. Further, since the second planar portions extend in both the axial direction and the radial direction, the plate-like members (junction conductor) are prevented from becoming increased in dimension along the circumferential direction.
The rotary electric machine may be coupled to one end of a speed reducer, and the electric power line joints may be disposed closer to the speed reducer than the stator in an axial direction of the rotary electric machine. Consequently, the external electric power line joints can be installed while taking into consideration the positional relationship between the external electric power line joints and the end of the speed reducer. Thus, depending on the layout, the dimension of the rotary electric machine can be reduced along the axial direction.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a fragmentary cross-sectional view of a vehicle, especially a cooling system thereof, in which there is incorporated a motor that serves as a rotary electric machine according to an embodiment of the present invention;
FIG. 2 is an enlarged fragmentary cross-sectional view showing flows of an oil coolant in the motor;
FIG. 3 is a fragmentary perspective view, partially cut away, of an electric power system of the vehicle;
FIG. 4 is a fragmentary cross-sectional view taken along line IV-IV of FIG. 3 ;
FIG. 5 is a perspective view of a side cover that functions as a portion of the cooling system;
FIG. 6 is a plan view, which is illustrated in a simplified form, showing the positions of through holes in a motor rotor;
FIG. 7 is a perspective view of a joint between a motor stator and a junction conductor;
FIG. 8 is a perspective view showing a positional relationship between the motor stator and the junction conductor;
FIG. 9 is a perspective view of a fusing member;
FIG. 10 is a front elevational view showing a positional relationship between fusing members and a terminal base;
FIG. 11 is a view showing a stator that is illustrated in FIG. 3 of JP 2009-017667 A;
FIG. 12 is a first perspective view of the terminal base with bus bars assembled thereon;
FIG. 13 is a second perspective view of the terminal base with the bus bars assembled thereon;
FIG. 14 is a view showing a positional relationship between a motor housing and the terminal base with the bus bars assembled thereon;
FIG. 15 is an exploded perspective view of the terminal base and the bus bars;
FIG. 16 is a perspective view of a second cover (insulating cover) with the bus bars assembled thereon;
FIG. 17 is a perspective view of the insulating cover;
FIG. 18 is a cross-sectional view, taken along line XVIII-XVIII of FIG. 16 , of the insulating cover, at a position where oil discharge ports are not present; and
FIG. 19 is a fragmentary cross-sectional view, taken along line XIX-XIX of FIG. 16 , of the insulating cover, at a position where an oil discharge port is present.
DESCRIPTION OF EMBODIMENTS
A. Embodiment
1. Description of Overall Arrangement
[1-1. Overall Arrangement]
FIG. 1 is a fragmentary cross-sectional view of a vehicle 10 , especially a cooling system (coolant supply unit) thereof, which incorporates a motor 12 as a rotary electric machine according to an embodiment of the present invention. FIG. 2 is an enlarged fragmentary cross-sectional view showing flows of an oil coolant 42 in the motor 12 . In FIG. 2 , the thick arrows represent flows of the oil coolant 42 . FIG. 3 is a fragmentary perspective view, partially cut away, of an electric power system of the vehicle 10 . FIG. 4 is a fragmentary cross-sectional view taken along line IV-IV of FIG. 3 . It should be noted that, for facilitating understanding of the present invention, FIGS. 1 and 2 are cross-sectional views taken along line I-I of FIG. 6 , to be described later. Further, a side cover 30 (to be described later) in FIGS. 1 and 2 is shown in cross section (taken along line I-I of FIG. 5 ) through all of an inlet hole 32 and first through third outlet holes 36 , 38 , 40 , to be described later (see FIG. 5 ).
As shown in FIG. 1 , the vehicle 10 has a speed reducer 14 , which serves as a gear mechanism, in addition to the motor 12 . A portion of the speed reducer 14 is disposed in the motor 12 .
The motor 12 serves as a drive source for generating a drive force F for the vehicle 10 . The motor 12 comprises a three-phase AC brushless motor for generating the drive force F for the vehicle 10 based on electric power supplied from a non-illustrated battery through a non-illustrated inverter. The motor 12 also regenerates electric power (regenerative electric power Preg) [W] in a regenerative mode, and outputs the regenerative electric power Preg to the battery in order to charge the battery. The regenerative electric power Preg may be output to a 12-volt system or a non-illustrated accessory device.
As shown in FIGS. 1 through 4 , the motor 12 has a motor rotor 20 (hereinafter also referred to as a “rotor 20 ”), a motor stator 22 (hereinafter also referred to as a “stator 22 ”), a resolver rotor 24 , a resolver stator 26 , a motor housing 28 , and the side cover 30 . The resolver rotor 24 and the resolver stator 26 jointly make up a resolver 31 .
[1-2. Cooling System]
(1-2-1. Side Cover 30 )
FIG. 5 is a perspective view of the side cover 30 , which functions as a portion of the cooling system. As shown in FIGS. 1, 2, and 5 , the side cover 30 has a single inlet hole 32 , a flow passage 34 , a single first outlet hole 36 , a single second outlet hole 38 , and a plurality of third outlet holes 40 . The first through third outlet holes 36 , 38 , 40 are supplied with an oil coolant 42 from a non-illustrated pump, which may be an electric pump or a mechanical pump.
As shown in FIGS. 1, 2, and 5 , according to the present embodiment, the oil coolant 42 is ejected or discharged from the side cover 30 toward the rotor 20 and the stator 22 .
More specifically, the first outlet hole 36 ejects or discharges the oil coolant 42 primarily toward a rotational shaft 50 of the rotor 20 . The second outlet hole 38 ejects or discharges the oil coolant 42 primarily toward a tubular member 52 of the rotor 20 . The third outlet hole 40 ejects or discharges the oil coolant 42 primarily toward the stator 22 . Each of the outlet holes 36 , 38 , 40 is in the form of a nozzle for ejecting or discharging the oil coolant 42 .
(1-2-2. Motor Rotor 20 )
(1-2-2-1. Rotational Shaft 50 )
As shown in FIGS. 1 and 2 , the rotational shaft 50 of the rotor 20 has an axial opening 53 for supplying the oil coolant 42 to the inside of the rotational shaft 50 , a single first axial flow passage 54 that extends along axial directions X 1 , X 2 (see FIG. 1 ), and a plurality of second axial flow passages 56 , which establish fluid communication along radial directions R 1 , R 2 (see FIG. 6 ) of the motor 12 between the first axial flow passage 54 and the outside of the rotational shaft 50 .
The oil coolant 42 , which is supplied from the first outlet hole 36 of the side cover 30 , is guided through the first axial flow passage 54 into the second axial flow passages 56 , and then is discharged through the second axial flow passages 56 from the rotational shaft 50 . The discharged oil coolant 42 is supplied to the inside of the rotor 20 or to a portion of the speed reducer 14 .
(1-2-2-2. Tubular Member 52 )
(1-2-2-2-1. General)
As shown in FIG. 2 , etc., the rotor 20 has, in addition to the rotational shaft 50 , a bottomed tubular member 52 , a rotor core 60 , and a rotor yoke 62 .
The tubular member 52 includes a bottom wall 70 fixed to the outer circumferential surface of the rotational shaft 50 near the side cover 30 , and a side wall 72 that extends in the axial direction X 2 from the outer edge of the bottom wall 70 . The side wall 72 opens remotely from the bottom wall 70 , i.e., the side wall 72 has an opening 74 remote from the bottom wall 70 . The speed reducer 14 has a planet gear 76 disposed in the tubular member 52 .
(1-2-2-2-2. Bottom Wall 70 )
As shown in FIG. 2 , the bottom wall 70 includes a base 80 , a first protrusive wall 82 , and a second protrusive wall 84 . The base 80 extends along the radial direction R 1 . The base 80 has a plurality of through holes 86 defined in a portion thereof. The through holes 86 extend along the axial directions X 1 , X 2 through the bottom wall 70 (base 80 ).
FIG. 6 is a plan view showing the positions of the through holes 86 in the motor rotor 20 , which is illustrated in a simplified form. As shown in FIG. 6 , according to the present embodiment, there are four through holes 86 , which are spaced at equal intervals. The oil coolant 42 , which is ejected from the side cover 30 toward the bottom wall 70 , is supplied through the through holes 86 to the inside of the tubular member 52 .
The first protrusive wall 82 projects toward the side cover 30 (along the direction X 1 ) from a portion positioned radially outward (along the direction R 1 ) of the through holes 86 . The first protrusive wall 82 has an annular shape. For this reason, if the oil coolant 42 , which is ejected or discharged from the side cover 30 toward the bottom wall 70 during rotation of the rotor 20 , does not enter the through holes 86 directly, then the oil coolant 42 remains in an inner circumferential region of the first protrusive wall 82 , i.e., a region surrounded by the base 80 and the first protrusive wall 82 , under centrifugal forces that act on the oil coolant 42 . Stated otherwise, the base 80 and the first protrusive wall 82 jointly provide a reservoir 88 for the coolant. Therefore, even if the oil coolant 42 does not enter the through holes 86 directly, the oil coolant 42 remains in the reservoir 88 and thereafter is supplied through the through holes 86 to the inside of the tubular member 52 .
The first protrusive wall 82 has a portion that overlaps with the axial opening 53 of the rotational shaft 50 , as viewed along the radial directions R 1 , R 2 of the rotor 20 . Therefore, the oil coolant 42 , which overflows the first axial flow passage 54 through the axial opening 53 , remains in the inner circumferential region of the first protrusive wall 82 under centrifugal forces or by gravity, and thereafter, the oil coolant 42 is supplied through the through holes 86 to the inside of the tubular member 52 . Consequently, the oil coolant 42 , which flows over the first axial flow passage 54 through the axial opening 53 , can be used to cool the rotor core 60 efficiently.
In addition, as shown in FIG. 2 , the first protrusive wall 82 has a greater-diameter portion 90 , which is progressively greater in diameter in a direction from the side cover 30 toward the base 80 of the bottom wall 70 , i.e., in the direction X 2 . The greater-diameter portion 90 makes it easy for the reservoir 88 to be formed radially inward of the first protrusive wall 82 , i.e., in the direction R 2 , thereby minimizing the amount of oil coolant 42 that does not enter into the tubular member 52 after being supplied radially inward of the first protrusive wall 82 , i.e., in the direction R 2 . In FIG. 2 , the first protrusive wall 82 is shown as being increased in diameter in both radial inward and radial outward directions. However, even if the first protrusive wall 82 is increased in diameter in the radial inward direction only, the first protrusive wall 82 is capable of operating in the aforementioned manner to offer the advantages described above.
The resolver rotor 24 , i.e., the rotor of a rotary sensor, is fixed to a radial outer surface of the first protrusive wall 82 , i.e., a surface thereof that faces in the direction R 1 . Therefore, the first protrusive wall 82 functions both to provide the reservoir 88 for the oil coolant 42 , and to retain the resolver rotor 24 . Consequently, the motor 12 can be simpler in structure than if a member for retaining the resolver rotor 24 were provided separately from the first protrusive wall 82 .
As shown in FIG. 2 , the second protrusive wall 84 projects toward the opening 74 (along the direction X 2 in FIG. 2 ) from a portion positioned radially outward (along the direction R 1 ) of the through holes 86 . The second protrusive wall 84 has an annular shape. A distal end of the second protrusive wall 84 overlaps with a portion of the planet gear 76 , as viewed along a radial outward direction of the rotor 20 (along the direction R 1 ). Therefore, the oil coolant 42 , which is guided by the second protrusive wall 84 , is supplied to a portion of the planet gear 76 when the oil coolant 42 is discharged under centrifugal forces in a radial outward direction (along the direction R 1 ).
(1-2-2-2-3. Side Wall 72 )
As shown in FIGS. 1 and 2 , the rotor core 60 and the rotor yoke 62 are fixed to a radial outer surface (which faces in the direction R 1 ) of the side wall 72 of the tubular member 52 . As described above, the oil coolant 42 is supplied from the side cover 30 to the inside of the tubular member 52 through the rotational shaft 50 or the bottom wall 70 of the tubular member 52 . Thereafter, as the oil coolant 42 moves along the side wall 72 while the rotor 20 rotates, the oil coolant 42 cools the rotor core 60 .
The oil coolant 42 , which has reached the side wall 72 , moves along the side wall 72 into the opening 74 from which the oil coolant 42 is discharged. Thereafter, the oil coolant 42 , which is discharged from the opening 74 , is pooled on the bottom (not shown) of the motor housing 28 , whereupon the oil coolant 42 is ejected or discharged again from the side cover 30 toward the rotor 20 or the stator 22 by the pump. Heat from the oil coolant 42 may undergo heat transfer by a cooler or a warmer, not shown, before the oil coolant 42 is ejected or discharged again.
(1-2-3. Motor Stator 22 )
The oil coolant 42 , which is supplied from the third outlet holes 40 of the side cover 30 , passes through the stator 22 while cooling various parts of the stator 22 , and drops onto the bottom of the motor housing 28 .
As will be described in detail later, even if the oil coolant 42 enters a second cover 182 (insulating cover) upon moving through the stator 22 , the oil coolant 42 is discharged through oil discharge ports 190 (see FIGS. 16, 17, and 19 ).
As shown in FIG. 2 , etc., the resolver stator 26 is disposed on the motor stator 22 radially outward of the resolver rotor 24 along the direction R 1 . The resolver stator 26 produces an output signal depending on the rotational angle of the resolver rotor 24 . Therefore, the resolver 31 is capable of detecting the rotational angle of the motor rotor 20 .
[1-3. Electric Power System]
(1-3-1. General)
As described above, FIG. 3 is a fragmentary perspective view, partially cut away, of the electric power system of the vehicle 10 in which the motor 12 , which serves as a rotary electric machine according to the present embodiment, is incorporated. FIG. 4 is a fragmentary cross-sectional view taken along line IV-IV of FIG. 3 .
In addition to the rotor 20 and the stator 22 , the electric power system of the motor 12 according to the present embodiment includes a harness 100 (external electric power lines 102 ) and a junction conductor 104 .
(1-3-2. Motor Stator 22 )
FIG. 7 is a perspective view of a joint between the motor stator 22 and the junction conductor 104 . FIG. 8 is a perspective view showing a positional relationship between the motor stator 22 and the junction conductor 104 .
The stator 22 includes coils 112 in a plurality of phases (phase U, phase V, phase W) wound on stator cores 110 with insulating members 111 interposed therebetween. As shown in FIG. 7 , the coils 112 have respective ends bundled into coil ends 114 in the respective phases. As shown in FIG. 7 , the coil ends 114 project radially outward (along the direction R 1 ). Reference should also be made to FIG. 7 of JP 2009-017667 A, which provides a description of the manner in which the ends of the coils 112 are bundled in the respective phases.
As shown in FIGS. 3, 4, 7, and 8 , the stator cores 110 are housed in a stator holder 116 (stator housing), which is disposed on a radial outward side (along the direction R 1 ).
(1-3-3. Harness 100 (External Electric Power Lines 102 )
The harness 100 includes external electric power lines 102 in the plural phases (phase U, phase V, phase W). The external electric power lines 102 refer to electric power lines, which connect the motor 12 and the non-illustrated inverter outside of the motor housing 28 . As shown in FIG. 4 , terminals 120 of the external electric power lines 102 are connected to the junction conductor 104 . According to the present invention, joints (external electric power line joints 122 ) between the terminals 120 and the junction conductor 104 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 (and the outer circumferential surface of the stator holder 116 ). Therefore, the overall dimension of the motor 12 along the directions R 1 , R 2 is small. The external electric power line joints 122 are positioned closer to the speed reducer 14 than the stator 22 along the axial directions X 1 , X 2 .
(1-3-4. Junction Conductor 104 )
The junction conductor 104 serves to electrically join (connect) the coils 112 and the external electric power lines 102 . The junction conductor 104 comprises fusing members 130 (coil-side conductors) in the respective phases, bus bars 132 a through 132 c (external electric power line-side conductors) in the respective phases, and a terminal base 134 . The fusing members 130 and the bus bars 132 a through 132 c jointly make up a junction.
(1-3-4-1. Fusing Members 130 )
FIG. 9 is a perspective view of a fusing member 130 . FIG. 10 is a front elevational view showing a positional relationship between the fusing members 130 and the terminal base 134 . As shown in FIGS. 7 and 9 , etc., each of the fusing members 130 is in the form of a bent plate.
More specifically, the fusing member 130 includes a coil connecting panel 140 , a terminal base connecting panel 142 , and an intermediate panel 144 disposed between the coil connecting panel 140 and the terminal base connecting panel 142 .
As shown in FIG. 9 , the coil connecting panel 140 has an opening 146 defined therein for insertion of the coil ends 114 . After the coil ends 114 have been inserted in the opening 146 , the tip end of the coil connecting panel 140 is biased in the direction indicated by the arrow A 1 in FIG. 9 so as to close the opening 146 , and the coil ends 114 and the coil connecting panel 140 are joined by being crimped with heat (see FIG. 7 , etc.). The joints between the coil ends 114 and the coil connecting panel 140 will hereinafter be referred to as “coil joints 147 ”.
As shown in FIGS. 3, 7, and 10 , the terminal base connecting panels 142 are fastened to the terminal base 134 by bolts 148 and nuts 150 (see also FIG. 15 ).
As seen from FIGS. 3, 7, and 10 , the coil connecting panel 140 , the terminal base connecting panel 142 , and the intermediate panel 144 according to the present embodiment lie in directions (the directions R 1 , R 2 ) perpendicular to the outer circumferential surface of the stator 22 (or the stator holder 116 ).
More specifically, the coil connecting panel 140 and the terminal base connecting panel 142 are disposed in circumferential directions (the directions C 1 , C 2 in FIG. 10 ) and radial directions (the directions R 1 , R 2 in FIG. 10 ). The thicknesswise directions of the coil connecting panel 140 and the terminal base connecting panel 142 are disposed parallel to the axial directions X 1 , X 2 and are not oriented toward the outer circumferential surface of the stator 22 . The intermediate panel 144 is disposed along axial directions (the directions X 1 , X 2 in FIG. 4 ) and radial directions (the directions R 1 , R 2 in FIG. 10 ). The thicknesswise direction of the intermediate panel 144 is located in close proximity to the circumferential directions C 1 , C 2 and is not oriented toward the outer circumferential surface of the stator 22 . The intermediate panel 144 is oriented in this manner for the following reasons.
If the intermediate panel 144 were disposed along the circumferential directions C 1 , C 2 and the axial directions X 1 , X 2 , for example, or stated otherwise, if the thicknesswise direction of the intermediate panel 144 were to lie parallel to the radial directions R 1 , R 2 , then the intermediate panel 144 would be disposed more closely to the outer circumferential surface of the stator 22 by the thickness dimension thereof. In such a case, for insulating the intermediate panel 144 from the outer circumferential surface of the stator 22 , it is necessary for the intermediate panel 144 to be spaced away from the outer circumferential surface of the stator 22 , which results in an increase in the radial dimensions of the motor 12 .
FIG. 11 shows a stator (hereinafter referred to as a “stator 200 ”), which is illustrated in FIG. 3 of JP 2009-017667 A. The stator 200 shown in FIG. 11 has a lead frame 202 , the thicknesswise direction of which faces toward the outer circumferential surface of a stator holder 204 . Therefore, in order to be insulated from each other, the lead frame 202 and the stator holder 204 need to be spaced from each other by a relatively large distance Lc.
In contrast thereto, according to the present embodiment, from the standpoint of insulating the intermediate panel 144 and the stator 22 from each other, since the intermediate panel 144 is disposed along the axial directions X 1 , X 2 and the radial directions R 1 , R 2 , it is possible to make the distance L 1 ( FIG. 10 ) between the intermediate panel 144 and the outer circumferential surface of the stator 22 shorter. The same feature holds true for the coil connecting panel 140 and the terminal base connecting panel 142 .
As shown in FIG. 10 , according to the present embodiment, each of the fusing members 130 includes the coil connecting panel 140 and the terminal base connecting panel 142 , which are staggered along the circumferential directions C 1 , C 2 . Therefore, when a worker or a manufacturing apparatus assembles the terminal base connecting panel 142 and thereafter assembles the coil connecting panel 140 in the axial direction X 2 , assembly of each of the terminal base connecting panel 142 and the coil connecting panel 140 is facilitated, because the respective members do not overlap with each other.
Furthermore, inasmuch as the intermediate panel 144 of the fusing member 130 is disposed along the axial directions X 1 , X 2 and the radial directions R 1 , R 2 , the intermediate panel 144 is less likely to overlap with the terminal base connecting panel 142 , thereby facilitating assembly of the intermediate panel 144 . Also, the dimensions of the fusing member 130 are prevented from increasing along the circumferential directions C 1 , C 2 .
(1-3-4-2. Bus Bars 132 a Through 132 c )
FIGS. 12 and 13 are first and second perspective views, respectively, of the terminal base 134 with the bus bars 132 a through 132 c assembled thereon. FIG. 14 is a view showing a positional relationship between the terminal base 134 with the bus bars 132 a through 132 c assembled thereon, and the motor housing 28 . FIG. 15 is an exploded perspective view of the terminal base 134 and the bus bars 132 a through 132 c . FIG. 16 is a perspective view of a second cover 182 (insulating cover) with the bus bars 132 a through 132 c assembled thereon. As shown in FIG. 15 , etc., each of the bus bars 132 a through 132 c comprises a plate-like member (e.g., a copper plate) that is blanked and bent.
As shown in FIG. 15 , etc., each of the bus bars 132 a through 132 c has one end (fusing member connector 160 ) fastened to the terminal base connecting panel 142 of the fusing member 130 by a bolt 148 and a nut 150 on the terminal base 134 . The other end of each of the bus bars 132 a through 132 c (external electric power line joints 162 ) is fastened to the terminal 120 of the external electric power line 102 by a bolt 164 ( FIG. 4 ) and a nut 166 . As shown in FIG. 4 , external electric power line joints 162 of the bus bars 132 a through 132 c , and external electric power line joints 122 of the terminals 120 of the external electric power lines 102 are positioned radially inward (along the direction R 2 ) of the outer circumferential surface of the motor stator 22 (or the stator holder 116 ).
As shown in FIGS. 15 and 16 , etc., each of the bus bars 132 a through 132 c includes a fusing member connector 160 , an external electric power line joint 162 , and an intermediate member 168 , although these respective elements differ in shape from each other.
More specifically, the intermediate member 168 of the bus bar 132 a in the first phase (e.g., the phase U) basically extends parallel to the axial directions X 1 , X 2 , and further includes a bent portion 170 disposed between the fusing member connector 160 and the external electric power line joint 162 , and a bent portion 172 disposed between the bent portion 170 and the external electric power line joint 162 .
The intermediate member 168 of the bus bar 132 b in the second phase (e.g., the phase V) basically extends parallel to the axial directions X 1 , X 2 , and further includes a bent portion 170 disposed between the fusing member connector 160 and the external electric power line joint 162 , a bent portion 172 disposed between the bent portion 170 and the external electric power line joint 122 , and a stepped portion 174 disposed between the bent portion 172 and the external electric power line joint 122 .
The intermediate member 168 of the bus bar 132 c in the third phase (e.g., the phase W) basically extends parallel to the axial directions X 1 , X 2 , and further includes a stepped portion 174 disposed between the fusing member connector 160 and the external electric power line joint 162 , and a bent portion 170 disposed between the stepped portion 174 and the external electric power line joint 122 .
Since the respective bus bars 132 a through 132 c are shaped in the foregoing manner, it is possible to maintain the external electric power line joints 162 in an array parallel to a horizontal plane H, as shown in FIG. 14 . As a result, it is easy to connect the bus bars 132 a through 132 c and the external electric power lines 102 to each other.
The bent portions 170 include bent regions, which are formed by blanking. The bent portions 172 are formed by bending portions of the bus bars 132 a , 132 b in the thicknesswise direction thereof. The stepped portions 174 are formed by bending portions of the bus bars 132 b , 132 c in the thicknesswise direction thereof.
When there is a change in temperature, the bent portions 172 or the stepped portions 174 are flexed to absorb extensions and contractions of the bus bars 132 a through 132 c . Therefore, stresses caused in the bus bars 132 a through 132 c when the temperature changes are reduced, thereby preventing the bus bars 132 a through 132 c from becoming damaged.
(1-3-4-3. Terminal Base 134 )
The terminal base 134 connects the fusing members 130 and the bus bars 132 a through 132 c to each other. As shown in FIG. 15 , etc., the terminal base 134 has a first cover 180 that covers a radial outer side (facing in the direction R 1 ) of the fusing members 130 , and further includes joints (intermediate joints 178 ) between the fusing members 130 and the bus bars 132 a through 132 c , a second cover 182 that covers portions of the lower surfaces of the bus bars 132 a through 132 c , and a third cover 184 that covers portions of the upper surfaces of the bus bars 132 a through 132 c.
As shown in FIGS. 15 and 16 , etc., the second cover 182 has prongs 186 with teeth 187 thereon. The third cover 184 includes recesses 188 defined at positions that are aligned with the prongs 186 . As shown in FIG. 13 , etc., the second cover 182 and the third cover 184 are coupled to each other when the prongs 186 engage within the recesses 188 .
The first cover 180 , the second cover 182 , and the third cover 184 of the terminal base 134 also function as insulating covers for insulating the bus bars 132 a through 132 c from surrounding components (the coils 112 of the stator 22 , etc.). Therefore, the second cover 182 will hereinafter also be referred to as an “insulating cover 182 ”.
As shown in FIG. 10 , etc., the intermediate joints 178 are positioned radially outward (along the direction R 1 ) of the outer circumferential surface of the motor stator 22 .
Further, as shown in FIG. 10 , etc., the coil joints 147 (the joints between the coil ends 114 and the fusing members 130 ) and the intermediate joints 178 (the joints between the fusing members 130 and the bus bars 132 a through 132 c ) are disposed on circumferential planes, portions of which have the same radius. In addition, the coil joints 147 and the intermediate joints 178 are disposed in positions that are mutually staggered circumferentially as viewed from the axial direction X 2 .
Therefore, when a worker or a manufacturing apparatus assembles the intermediate joints 178 , and thereafter assembles the coil joints 147 in the axial direction X 2 , it is easy to assemble each of the intermediate joints 178 and the coil joints 147 , because the intermediate joints 178 and the coil joints 147 do not overlap with each other.
FIG. 17 is a perspective view of the insulating cover 182 (second cover 182 ). FIG. 18 is a cross-sectional view, taken along line XVIII-XVIII of FIG. 16 , of the insulating cover 182 , at a position where oil discharge ports 190 are not present. FIG. 19 is a fragmentary cross-sectional view, taken along line XIX-XIX of FIG. 16 , of the insulating cover 182 , at a position where an oil discharge port 190 is present.
As shown in FIG. 4 , etc., the insulating cover 182 is disposed between the outer circumferential surface of the motor stator 22 (or the stator holder 116 ) and the bus bars 132 a through 132 c at the coil ends 114 (in the axial direction X 1 ). The insulating cover 182 also extends along the axial direction X 2 .
As shown in FIG. 18 , etc., the insulating cover 182 has a bottom surface 192 , which is inclined to the horizontal plane H (along the directions X 1 , X 2 and the directions Y 1 , Y 2 ), for thereby guiding the oil coolant 42 downwardly by gravity.
As shown in FIGS. 17 and 19 , etc., the insulating cover 182 has partition walls 194 for securing the bus bars 132 a through 132 c and for insulating the bus bars 132 a through 132 c from each other.
As shown in FIGS. 18 and 19 , a predetermined gap exists between the lower surfaces of the bus bars 132 a through 132 c and the bottom surface 192 of the insulating cover 182 . Such a gap is created as a result of the bus bars 132 a through 132 c being fitted in the insulating cover 182 , rather than being insert-molded. The gap may be created intentionally due to the shapes of the bus bars 132 a through 132 c , or may be created due to tolerances. If the bus bars 132 a through 132 c are insert-molded, then if the bus bars 132 a through 132 c were to become deformed due to a change in temperature, a resin that is held in intimate contact with the bus bars 132 a through 132 c tends to crack. However, since the gap is present between the bus bars 132 a through 132 c and the insulating cover 182 , the bus bars 132 a through 132 c are allowed to become deformed, thereby preventing damage to the insulating cover 182 due to a change in temperature.
The insulating cover 182 includes the oil discharge ports 190 , which are defined in the bottom surface 192 and extend vertically through the bottom surface 192 . The oil discharge ports 190 are positioned at corners where the bottom surface 192 and the partition walls 194 cross each other, and in particular, the oil discharge ports 190 are disposed at corners that are positioned relatively on the lower side when the insulating cover 182 is installed. The oil discharge ports 190 are disposed on both upper and lower sides of a step that is formed on the insulating cover 182 .
Furthermore, as shown in FIG. 8 , etc., the oil discharge ports 190 are spaced adequately from the stator 22 along the axial direction X 2 , so that the oil discharge ports 190 do not impair the insulation between the stator 22 and the bus bars 132 a through 132 c.
The oil coolant 42 , which is supplied from the side cover 30 to the motor stator 22 , may potentially pass through the inside of the stator 22 into the terminal base 134 . If the oil discharge ports 190 according to the present embodiment are not defined in the insulating cover 182 , then the oil coolant 42 is likely to be retained on the insulating cover 182 , thereby increasing the likelihood of a short circuit between the bus bars 132 a through 132 c , and leading to deterioration of the insulating cover 182 .
According to the present embodiment, since the insulating cover 182 has the oil discharge ports 190 defined therein, the oil discharge ports 190 are effective to prevent the oil coolant 42 from being retained on the insulating cover 182 .
2. Advantages of the Present Embodiment
According to the present embodiment, as described above, the external electric power line joint 122 is shifted from the motor stator 22 in the axial direction X 2 , and is positioned radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 (see FIG. 4 ). Therefore, the dimension of the motor 12 along the radial directions R 1 , R 2 is reduced by the extent to which the external electric power line joint 122 is disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , rather than being disposed radially outward (along the direction R 1 ) of the outer circumferential surface of the stator 22 .
The junction conductor 104 according to the present embodiment comprises the fusing members 130 (coil-side conductors) including the coil joints 147 , and the bus bars 132 a through 132 c (electric power line-side conductors), which are separate from the fusing members 130 and include the external electric power line joint 122 . The intermediate joints 178 , which interconnect the fusing members 130 and the bus bars 132 a through 132 c , are positioned radially outward (along the direction R 1 ) of the outer circumferential surface of the stator 22 .
When the stator 22 is assembled on the motor housing 28 in the axial direction X 2 , if a portion of the external electric power line joint 122 is positioned radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , it may be difficult to work on the external electric power line joint 122 from the axial direction X 2 . However, according to the above structure, the bus bars 132 a through 132 c and the external electric power lines 102 are connected to make up the external electric power line joints 122 , and thereafter, the fusing members 130 and the bus bars 132 a through 132 c are connected to make up the intermediate joints 178 , thereby enabling the coils 112 and the external electric power lines 102 to be connected to each other. Consequently, assembly of the junction conductor 104 can be simplified.
According to the present embodiment, respective portions of the coil joints 147 and the intermediate joints 178 are staggered from each other on circumferential planes, which have the same radius as viewed from the axial direction X 2 (see FIG. 10 , etc.). This feature prevents the motor 12 from being increased in dimension along the radial directions R 1 , R 2 of the motor 12 . In addition, since the intermediate joints 178 can be worked on along the axial direction X 2 , assembly of the fusing members 130 is facilitated.
According to the present embodiment, the coil ends 114 of the coils 112 project radially outward (along the direction R 1 ). The coil joints 147 are made up of the junction conductor 104 and the coil ends 114 , which are connected to each other. The junction conductor 104 includes the bent fusing members 130 (plate-like members). The fusing members 130 include the coil joints 147 , each of which includes the coil connecting panel 140 (first planar portion), which extends along the radial directions R 1 , R 2 and the circumferential directions C 1 , C 2 , and the intermediate panel 144 (second planar portion), which is coupled to the coil connecting panel 140 and extends in the axial direction X 2 and the radial direction R 1 radially outward (along the direction R 1 ) of the outer circumferential surface of the stator 22 (see FIGS. 7 and 9 , etc.).
With the above arrangement, each of the coil connecting panel 140 and the intermediate panel 144 lies perpendicular to the outer circumferential surface of the stator 22 . Therefore, the fusing members 130 can easily be spaced from the outer circumferential surface of the stator 22 . Accordingly, the insulation between the fusing members 130 and the outer circumferential surface of the stator 22 is prevented from being lowered. Since the intermediate panel 144 extends in the axial direction X 2 and the radial direction R 1 , the fusing members 130 are prevented from becoming increased in dimension along the circumferential directions C 1 , C 2 .
According to the present embodiment, the motor 12 is coupled to one end (i.e., the planet gear 76 ) of the speed reducer 14 , and the external electric power line joints 122 are disposed more closely to the speed reducer 14 than the stator 22 along the axial directions X 1 , X 2 . Consequently, the external electric power line joints 122 can be installed in view of the positional relationship between the external electric power line joints 122 and the end of the speed reducer 14 . In view of the layout according to the present embodiment, the dimension of the motor 12 along the axial directions X 1 , X 2 can be reduced.
B. Modifications
The present invention is not limited to the above embodiment, but various other arrangements may be employed based on the disclosed content of the present description. For example, the present invention can employ the following arrangements.
1. Objects to which the Present Invention is Applicable
In the above embodiment, the motor 12 is mounted on the vehicle 10 . However, the present invention is applicable to other situations in which the motor 12 may be employed. For example, although the motor 12 is used to propel the vehicle 10 in the above embodiment, the motor 12 may be used in other applications in the vehicle 10 (e.g., an electric power steering system, an air conditioner, an air compressor, etc.). Alternatively, the motor 12 may be used on industrial machines, home electric appliances, etc.
2. Motor 12
In the above embodiment, the motor 12 is a three-phase AC motor. However, the motor 12 may be another type of AC motor or a DC motor, for example, which is cooled by a cooling fluid, or which is of a reduced size. In the above embodiment, the motor 12 comprises a brushless motor. However, the motor 12 may be a brush motor. In the above embodiment, the motor stator 22 is disposed radially outward (along the direction R 1 ) of the motor rotor 20 (see FIG. 1 , etc.). However, the motor stator 22 may be disposed radially inward of the motor rotor 20 .
3. Resolver 31
In the above embodiment, the resolver rotor 24 is mounted on the first protrusive wall 82 . However, the resolver rotor 24 may be fixed to another member other than the first protrusive wall 82 , insofar as the oil coolant 42 is capable of being supplied from the bottom wall 70 of the tubular member 52 to the inside of the tubular member 52 , or in view of the structure of the electric power system.
4. Cooling System
[4-1. Cooling Fluid]
In the above embodiment, the oil coolant 42 is used as a cooling fluid. However, rather than the oil coolant 42 , another cooling fluid (e.g., water or the like) may be used from the standpoint of effecting the cooling function. However, in this case, potentially, the other cooling fluid may not be used as a lubricant for lubricating the gear mechanisms such as the planet gear 76 , etc.
[4-2. Tubular Member 52 ]
In the above embodiment, the planet gear 76 , which is coupled to the rotational shaft 50 , is disposed in the tubular member 52 . However, a different type of gear mechanism may be disposed in the tubular member 52 . Alternatively, other members may be disposed in the tubular member 52 that are cooled by the cooling medium. For example, a frictional engagement unit (clutch mechanism), which is coupled to the rotational shaft 50 , may be disposed in the tubular member 52 .
By disposing a frictional engagement unit in the tubular member 52 , it is possible to reduce the dimension of the motor 12 along the axial directions X 1 , X 2 . Further, in addition to cooling the rotor core 60 , it also is possible to cool or lubricate the frictional engagement unit (assuming that the cooling fluid doubles as a lubricating oil). Therefore, as opposed to providing the cooling structure for the rotor core 60 and the cooling structure for the frictional engagement unit separately from each other, the structure can be made simpler.
5. Electric Power System
[5-1. Junction Conductor 104 ]
In the above embodiment, the junction conductor 104 is made up of the fusing members 130 and the bus bars 132 a through 132 c . However, the junction conductor 104 is not limited to such a structure, insofar as the terminals 120 of the external electric power lines 102 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , for example. For example, the coil ends 114 and the external electric power lines 102 may be connected by either the fusing members 130 or the bus bars 132 a through 132 c.
Furthermore, the shapes of the fusing members 130 or the bus bars 132 a through 132 c may be changed, insofar as the terminals 120 of the external electric power lines 102 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , for example. For example, in the above embodiment (see FIG. 4 ), although the bus bars 132 a through 132 c basically lie parallel to the axial directions X 1 , X 2 , the bus bars 132 a through 132 c may be inclined to the axial directions X 1 , X 2 . For example, the bus bars 132 a through 132 c may be inclined from an upper left position toward a lower right position in FIG. 4 .
In the above embodiment, the intermediate joints 178 , which connect the terminal base connecting panels 142 of the fusing members 130 and the fusing member connectors 160 of the bus bars 132 a through 132 c , are disposed radially outward (along the direction R 1 ) of the outer circumferential surface of the motor stator 22 . However, insofar as the terminals 120 of the external electric power lines 102 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , for example, the intermediate joints 178 may also be disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 .
In the above embodiment, the respective portions of the coil joints 147 and the intermediate joints 178 are staggered mutually on circumferential planes that have the same radius as viewed from the axial direction X 2 (see FIG. 10 , etc.). However, insofar as the terminals 120 of the external electric power lines 102 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , for example, the respective portions of the coil joints 147 and the intermediate joints 178 need not necessarily be disposed on circumferential planes having the same radius as viewed from the axial direction X 2 .
In the above embodiment, the coil connecting panels 140 of the fusing members 130 extend along the radial directions R 1 , R 2 and the circumferential directions C 1 , C 2 , and the intermediate panels 144 are coupled to the coil connecting panels 140 so as to extend along the axial direction X 2 and the radial direction R 1 radially outward (along the direction R 1 ) of the outer circumferential surface of the stator 22 . However, insofar as the coil ends 114 and the external electric power lines 102 are connected in such a manner that the terminals 120 of the external electric power lines 102 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , for example, the intermediate panels 144 may extend along the axial directions X 2 and the circumferential directions C 1 , C 2 , or stated otherwise, the intermediate panels 144 may be disposed parallel to the outer circumferential surface of the stator 22 , for example.
In the above embodiment, the motor 12 is coupled to the end of the speed reducer 14 , and the external electric power line joint 122 is disposed closer to the speed reducer 14 than the stator 22 along the axial directions X 1 , X 2 . However, insofar as the coil ends 114 and the external electric power lines 102 are connected in such a manner that the terminals 120 of the external electric power lines 102 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , for example, the external electric power line joint 122 may be disposed opposite to the speed reducer 14 across the stator 22 along the axial directions X 1 , X 2 .
In the above embodiment, the external electric power line joint 122 is disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 . However, insofar as the function of the insulating cover 182 can be fulfilled, the external electric power line joint 122 may be disposed radially outward (along the direction R 1 ) of the outer circumferential surface of the stator 22 .
[5-2. Insulating Cover 182 ]
In the above embodiment, the insulating cover 182 is provided for the bus bars 132 a through 132 c . However, insofar as the terminals 120 of the external electric power lines 102 are disposed radially inward (along the direction R 2 ) of the outer circumferential surface of the stator 22 , for example, the insulating cover 182 may be dispensed with. If the insulating cover 182 is dispensed with, then the length of the fusing members 130 along the axial direction X 2 preferably is increased in order to provide insulation between the stator 22 and the bus bars 132 a through 132 c.
In the above embodiment, the number and layout of the oil discharge ports 190 are as shown in FIGS. 16 and 17 . However, insofar as the oil coolant 42 is capable of being discharged through the oil discharge ports 190 , it is sufficient to provide at least one oil discharge port 190 , and the layout of the oil discharge ports 190 can be changed appropriately.
In the above embodiment, the bus bars 132 a through 132 c extend along the axial direction X 2 from the outer circumferential side of the stator 22 . However, the bus bars 132 a through 132 c may be positioned in a different location, insofar as insulation can be provided between the stator 22 and the bus bars 132 a through 132 c and the oil coolant 42 can be discharged through the oil discharge ports 190 . For example, the bus bars 132 a through 132 c may extend radially outward (along the direction R 1 ) from the outer circumferential surface of the stator 22 . Further, the insulating cover 182 may be disposed between the bus bars 132 a through 132 c and the outer circumferential surface of the stator 22 .
In the above embodiment, the insulating cover 182 includes the partition walls 194 , which are positioned in plural phases between the bus bars 132 a through 132 c . However, the partition walls 194 may be dispensed with, insofar as sufficient insulation can be provided between the stator 22 and the bus bars 132 a through 132 c , and the oil coolant 42 can still be discharged through the oil discharge ports 190 .
In the above embodiment, the bottom surface 192 of the insulating cover 182 is inclined with respect to the horizontal plane H. However, the bottom surface 192 may lie parallel to the horizontal plane H, insofar as sufficient insulation can be provided between the stator 22 and the bus bars 132 a through 132 c , and the oil coolant 42 can still be discharged through the oil discharge ports 190 .
In the above embodiment, the bus bars 132 a through 132 c include the bent portions 172 , which are made up of portions of the plate-like members that are bent in the thicknesswise direction. The number or layout of the bent portions 172 may be changed, or the bent portions 172 may be dispensed with, insofar as sufficient insulation can be provided between the stator 22 and the bus bars 132 a through 132 c , and the oil coolant 42 can still be discharged through the oil discharge ports 190 . | A relay conductor of a rotating electrical machine is provided with: a coil connector that is connected to a coil on one side of a rotating shaft and further to the outside in the radial direction than the coil; a power line connector that is connected to an external power line on the other side of the rotating shaft; and relays that extend in the axial direction of the rotating shaft, and link the coil connector and the power line connector. At least a portion of the power line connector is positioned closer to the inner diameter side of the rotating electrical machine than the outer peripheral surface of a stator. | 7 |
RELATED APPLICATION
This application is a continuation-in-part application from U.S. patent application Ser. No. 278,240, filed Nov. 30, 1988, now abandoned.
FIELD OF THE INVENTION
This invention relates to a transverse leaf spring-type suspension for an automobile.
BACKGROUND OF THE INVENTION
A transverse leaf spring type suspension including a leaf spring mounted transversely of a car body so as to serve also as a lower arm or upper arm is disclosed, for example, in Japanese Disclosure Gazette No. 1983-501626 (International Publication No. WO 83/01758). The suspension of this type can do away with both the coil spring and the stabilizer.
FIG. 4 of the accompanying drawing schematically shows the leaf spring 1 included in the conventional suspension of this type in which the leaf spring 1 serves also as the lower arm, and the wheels 2. The wheels 2 are operatively associated by the respective knuckles with the opposite ends of the leaf spring 1. This leaf spring 1 has a linear longitudinal axis perpendicular to the central axis 0 of the car body and is supported by the car body at two intermediate support points P.
However, it will be impossible to mount the leaf spring 1 linearly between the right and left wheels 2 when various components such as the engine, the transmission, the differential gear and an axle beam are positioned between these wheels 2.
FIG. 5 illustrates a relationship between the upper arms 3 and the associated wheels 2. To obtain a suspension geometry for high maneuverability and stability, each rocking shaft L of the associated suspension arm, such as the upper arm 3, makes an angle with the central axis 0 of the car body. When the linear leaf spring 1 is employed in such suspension, the axis of the leaf spring 1 will not be perpendicular to the rocking shafts L, causing a torsional moment to be exerted on the leaf spring 1 at its support points as the wheels 2 move vertically. To achieve a lightweight vehicle, the leaf spring 1 may be formed by use of suitable synthetic resin, such as fiberglass reinforced plastic (FRP), but a leaf spring 1 made of such material will not be adequately resistant to the torsional moment and, therefore, the linear leaf spring 1 will be inadequate in this case.
SUMMARY OF THE INVENTION
In view of these problems, a primary object of this invention is to provide a transverse leaf spring type suspension adapted to be mounted between the right and left wheels even when the car components, such as the engine, are present between the wheels.
Another object of this invention is to provide a leaf spring type suspension having a leaf spring adapted to be free from any significant torsional moment produced due to a vertical movement or other movements of the wheels when the leaf spring is made of material that is unable to provide adequate resistance to such torsional moment.
The objects set forth above are achieved, in accordance with this invention, by a suspension having a transverse leaf spring which has its longitudinal axis extending transversely of the car body, with opposite ends of which the right and left wheels are operatively associated, and which is supported at its longitudinally intermediate points by the car body, characterized in that the leaf spring is curved in the direction in which the car moves ahead or rearwardly.
Such objects are also achieved, particularly when the leaf spring is made of material that may be unable to provide adequate resistance to a torsional moment, according to this invention, by a suspension having a transverse leaf spring which has its longitudinal axis extending transversely of a car body, with opposite ends of which the right and left wheels are operatively associated, and which is supported at two or more intermediate points along its length by the car body, characterized in that said leaf spring comprises nonlinear or curved portions defined between the support points and curved in the direction in which the car moves ahead or rearwardly and linear portions extending from the outermost support points to the respective adjacent ends.
This invention permits the engine to be disposed adjacent the curved portions.
Furthermore, the aforementioned linear portions may be oriented so as to extend substantially perpendicularly with respect to the associated rocking axis of the suspension arms in order that these linear portions are rocked around the respective support points with the consequence that the torsional moment that may be exerted on these support points is reduced to the minimum level.
Elasticity of the leaf spring forming a part of the suspension reduces the amount of vibration of the car during its running from being transmitted to the car body and elements forming the support points between the leaf spring and the car body are particularly designed to enhance this characteristic.
BRIEF DESCRIPTION OF THE DRAWINGS
The transverse leaf spring type suspension of the invention, as used with the front wheels of a front engine-front drive (FF) car and having the leaf spring serving also as the lower arm, is illustrated, by way of example, in the accompanying drawings in which:
FIG. 1. is a plan view schematically illustrating a relationship between a curved leaf spring and car components, such as wheels and an engine;
FIG. 2 is a schematic front view corresponding to FIG. 1;
FIG. 3 is a plan view similar to FIG. 1, illustrating a transverse leaf spring comprising curved portions and linear portions;
FIG. 4 is a plan view schematically illustrating the transverse leaf spring type suspension of the prior art;
FIG. 5 is a plan view schematically illustrating a relationship between respective upper arm rocking shafts and the central axis of a car body.
FIG. 6 is a view similar to FIG. 1 illustrating a first modified embodiment of the invention; and
FIG. 7 is a view, similar to FIG. 2, illustrating deflection of the spring as the wheels move vertically;
FIG. 8 is a view illustrating a typical support arrangement capable of use in practice of the present invention;
FIG. 9 is a view, partly in section, illustrating one element of the support arrangement of FIG. 8 in greater detail;
FIG. 10 is a partial perspective view illustrating the configuration of the spring member operative in the support element of FIG. 9;
FIG. 11 is a view, partly in section, illustrating the other element of the support arrangement of FIG. 8 in greater detail;
FIG. 12 is a partial perspective view of the support element of FIG. 11;
FIG. 13 is a view, partly in section, illustrating a modified embodiment of the support element of FIG. 9;
FIG. 14 is a view, partly in section, illustrating another modified embodiment of the support element of FIG. 9;
FIG. 15 is a partial perspective view of the support element of FIG. 14; and
FIG. 16 is a partial perspective view of yet another embodiment of the support element of FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The transverse leaf spring type suspension constructed in accordance with the present invention will be described generally, by way of example, with reference to FIGS. 1 through 3 of the accompany drawings.
Referring to FIG. 2, which is a front view, the suspension is schematically illustrated as being mounted in association with the front wheels of a FF car. It includes a leaf spring 11 having its longitudinal axis extending transversely of the car body 10. The leaf spring 11 serves as a lower arm and lower ends of the respective knuckles 12 which are operatively connected with opposite ends of the leaf spring 11 through means such as ball joints. Upper arms 13 are supported by associated rocking shafts L mounted for rocking movement with respect to the car body 10 and pivotally connected at ends remote from the respective rocking shafts L to the upper ends of the respective knuckles 12. Knuckle shafts 12a rotatably support the respective wheels 14. There are provided adjacent the opposite ends of the leaf spring 11 strut dampers 15 the upper ends of which support the car body 10. The leaf spring 11 is supported at two intermediate points P along its length on the car body 10 by the interposition of associated rubber mounts 16 or by support elements described in detail hereinafter. Reference symbol 0 designates the central axis of the car body.
As seen in FIG. 1, which is a schematic plan view, the leaf spring 11 is curved in the direction of the longitudinal axis of the car so that an engine 17 and a transmission 18 may be disposed in the space provided by this curved portion.
The suspension shown by FIGS. 1 and 2 operates in the manner described hereinafter. Referring to FIG. 7, vertical movement of the wheels causes the respective upper arms 13 to be rocked around the associated rocking shafts L. Simultaneously, the portions of the leaf spring 11 extending from the respective support points indicated as P A and P B to the adjacent ends pivot with respect to the associated support points as the spring deflects in the manner indicated by the broken line 11'. Thus, the elasticity of the leaf spring 11 allows such vertical movement of the wheels 14 relative to the car body 10 while minimizing the transmission of vibration to the car body 10.
Such car components as the engine 17 and the transmission 18 can be located in the space provided by the curved portion of the leaf spring 11. Consequently, a suspension having the transversely curved leaf spring 11 of the invention can be employed even when components such as an engine 17 are present between the right and left wheels 14.
FIG. 3 is a plan view similar to FIG. 1 and schematically illustrates a leaf spring 21 having a configuration, which is preferable, particularly when the leaf spring 21 is made of a material that is unable to provide an adequate resistance to a possible torsional moment. The leaf spring 21 of this suspension is provided with right and left support points P and has a portion extending between these support points P that is curved in the direction in which the car moves rearwardly to form a curved portion 21a. Portions extending from the respective support points P to the adjacent ends of the leaf spring 21 each form linear portions 21b having orientations defined respectively by tangent lines extending from the respective support points P of said curved portion 21a. These linear portions 21b extend toward the associated wheels 14 substantially perpendicularly with respect to the respective rocking shafts L of the upper arms 13, each of the rocking shafts L making an angle with respect to the central axis 0 of the car. The wheels 14 are operatively associated with the spring 21 in the same manner as has previously been mentioned with respect to spring 11, with the outer ends of the respective linear portions 21b attaching the knuckles 12.
With particular reference to FIG. 7 the described suspension operates as follows. As the wheels 14 move vertically the upper arms 13 are caused to pivot due to the action of the rocking shafts L in their mounts. Simultaneously therewith the leaf spring 11 deflects under the influence of the force F, as indicated by the broken line 11', so that the ends of the leaf spring are rocked about the respective support points, here designated as P A and P B , respectively. In this way the transmission of vibration to the car body is substantially avoided.
In the practice of the disclosed invention the support points P A and P B are preferably defined by support elements that are particularly configured to control the form of movement undergone by the leaf spring 11. For example, as shown in FIG. 8 the support point indicated as P A comprises a supporting arrangement within which movement of the spring 11 is substantially restricted to pivotal movement. Support point P B , on the other hand, as shown in FIG. 11 is structured so that the leaf spring can move both pivotally and linearly in the direction of its longitudinal axis. Thus, the support element providing support at point P A and designated generally by the reference numeral 25 in FIGS. 9 and 10 comprises a generally cylindrical body portion 26 integrally formed on the leaf spring 11 with its axis of revolution extending substantially perpendicularly of the longitudinal axis of the spring. The body portion 26 is received in a mount 27 which, as shown in FIG. 9, may be formed by metal bracket members 28 and 29 which are attached to the car body, as for example, by threaded connectors 30. The bracket members 28 and 29 are each provided with an arcuate recess 31 to which is bonded by adhesive, or the like, a resilient pad 32 for receiving the spring body portion 26 in a manner to restrict its movement to a pivotal movement as indicated by the arrow 33. The resilient pad 32 is preferably formed of a hard rubber or of equivalent vibration-damping material.
The support element intended for use at support point P B is indicated generally as 34 in FIGS. 11 and 12. This element comprises a pair of resilient pads 35 and 36 joined, as by means of adhesive bonding, to opposite surfaces of the leaf spring 11 and extending transversely of the longitudinal axis thereof. These pads 35 and 36, which are formed of hard rubber or equivalent material are retained between a pair of support rods 37 and 38 that extend between and are rigidly fixed to suspension brackets 39. As shown in the drawing figures the surfaces 40 and 41 of the pads 35 and 36 engaged by the support rods 37 and 38 are arcuately formed of a radius that is substantially greater than the radius of the respective support rods. Consequently, at this support point, P B , the leaf spring can readily accommodate both pivotal movement, indicated by the arrow 42 and linear movement, indicated by the arrow 43, parallel to the longitudinal axis of the spring.
The support point designated P A , can be effectively formed by alternate structural arrangements that essentially restrict movement of the spring 11 to pivotal movement. Thus, in FIG. 13 the integrally formed body portion 26 of FIGS. 9 and 10 is replaced by a pair of convexly formed metal members 44 joined by welding, or the like, to opposite surfaces of the spring 11. As shown, the members 44 cooperate to form a body portion adapted to be received between recessed brackets containing resilient mounting pads similar to those shown in FIG. 9.
FIG. 14 illustrates another embodiment of support element suitable for use at support point P A . In this embodiment the mounting brackets, indicated as 45 and 46, are provided with convex bearing surfaces 47 to which resilient pads 35 and 36 are attached. The leaf spring 11, on the other hand, is formed with an integral body portion 48 defined by projections 49 extending from opposite sides of the spring and containing arcuately formed concave recess surfaces 50 adapted to receive the convex bearing surfaces 47 of the respective mounts with the interposed resilient pads 35 and 36.
Yet another embodiment of support element suitable for use at support point P A is shown in FIG. 16. In this embodiment the spring 11 is provided with an integrally formed body portion 51 containing a transverse bore 52 for reception of a bearing member, such as roller bearing 53. In this embodiment of the invention the support point P A includes a pair of oppositely spaced brackets 54 that are secured to the car body. An axle rod 55 extends between, and has its ends fixed to, the brackets 54. As shown, the bearing inner race 56 is secured to the axle rod 55 with the outer race 57 being secured to the surface of the bore 52.
As shown in FIG. 1, where the leaf spring 11 possesses portions extending outwardly from the respective support points P to the adjacent ends which are also curved, these portions are not perpendicular to the rocking shafts L of the associated upper arms 13 but have their orientations varying point to point. Consequently, the direction of the force exerted on each point along said portions varies as the wheels 14 move vertically, producing a high torsional moment exerted on the support points P. Accordingly, the leaf spring 11 of this configuration is undesirable in regard to the strength required to resist such high torsional moment and, when the leaf spring 11 is made of a synthetic resin, such as FRP, adequate durability cannot be expected.
On the other hand, if the linear portions 21b are made to extend substantially perpendicularly with respect to the associated rocking shafts L, as in the leaf spring 21 shown by FIG. 3, the torsional moment, which may be exerted on each of said linear portions 21b, will be of a substantially lower value than that exerted on the corresponding portion which is curved. Accordingly, the leaf spring 21 may be made of FRP, or other synthetic resin.
Although the described embodiments have been illustrated with the leaf spring serving as the lower arm, it is also possible, within the scope of this invention, as shown in FIG. 6, that the leaf spring can serve alternatively as the upper arm, or the leaf spring can be provided separately of the suspension arms. Furthermore, although the embodiment has been discussed above in connection with the front wheels of a FF car, the suspension of this invention may be also mounted on the rear wheels of a front engine-rear drive (FR) car.
As will be apparent from the foregoing description, the transverse leaf spring type suspension constructed in accordance with this invention has the leaf spring so curved as to define a space within which the car components such as the engine and the differential gear can be positioned. Accordingly, the transverse leaf spring of the invention may be adopted even when such car components are present between the right and left wheels. Moreover, when the suspension arms have the rocking shafts each making an angle with respect to the central axis of the car body, the invention allows the leaf spring to extend substantially perpendicularly with respect to these rocking shafts, so that the torsional moment which may be exerted on this leaf spring is smaller than that exerted on a corresponding linear leaf spring of convention design. Consequently, the durability of the leaf spring is thereby improved.
By forming the portions of the leaf spring extending from the respective points at which the leaf spring is supported on the car body to the free ends thereof as linear portions, it is possible to make the leaf spring extend substantially perpendicularly with respect to the respective rocking shafts of the suspension arms. Thereby, the torsional moment exerted on the leaf spring is further reduced from that which would be exerted on the leaf spring that is curved along its full length, and synthetic resin, such as FRP, can be used as a material for such a leaf spring. Such reduction in torsional movement is still further enhanced when movement of the leaf spring is restricted, as by means of the support elements described herein.
Thus, it is possible to provide a light weight leaf spring and, correspondingly, a light weight car. Furthermore, the respective rocking shafts of the suspension arms can be inclined with respect to the central axis of the car body, increasing the degree of freedom for design and achieving the transverse leaf spring type suspension having a suspension geometry more preferable for maneuverability and stability.
It should be further understood that, although a preferred embodiment of the invention has been illustrated and described herein, changes and modifications can be made in the described arrangement without departing from the scope of the appended claims. | Disclosed is a suspension having an improved transverse leaf spring with its longitudinal axis extending transversely of a car body. The leaf spring is operatively associated at opposite ends with the right and left wheels of a car and is curved along its intermediate length in the direction in which the car moves ahead or back. The curved portion may be along a full length of the leaf spring or along a length defines between support points on the leaf spring, and in the latter case, lengths extending from the respective support points to the ends of the leaf spring most adjacent thereto remain linear to form linear portions extending substantially perpendicularly with respect to respective suspension arm rocking shafts. Various forms of support elements are described for securing the leaf spring for only pivotal movement about one of the support points and both pivotal and linear movement about the other thereof. | 1 |
TECHNICAL FIELD
[0001] This disclosure generally relates to cloud computing. More particularly, and without limitation, this disclosure relates to an automated approach to defining a new resource for a cloud computing system.
DESCRIPTION OF THE RELATED ART
[0002] Cloud computing systems are becoming increasingly popular for a variety of reasons. One aspect of the proliferation of cloud computing is that various cloud providers are introducing proprietary protocols or standardized Application Programming Interfaces (APIs). As a result, interaction with the various cloud systems typically requires adding or updating a list of supported APIs.
[0003] For example, a cloud computing management system associated with a cloud that includes cloud elements from different providers may need up-to-date records of the APIs offered by the various elements of the system and expose those same APIs for use to the customers of the management system. Maintaining such records consumes valuable development resources.
[0004] Additionally, cloud vendor API structures typically require different parameters (compared to another vendor's parameters) to realize the same function. This presents significant challenges as using a relatively straight-forward approach to supporting such API structures may yield complicated code structures and data models that are difficult to maintain. With additional APIs and vendors entering the cloud computing market at an increasing rate, these challenges become even more daunting and currently proposed solutions become un-scalable over time.
SUMMARY
[0005] Embodiments of this invention streamline the process of defining new resources for a cloud computing system by automating a portion of the resource creation and reducing the amount of time and effort required by a programmer.
[0006] An illustrative cloud computing manager device includes data storage and at least one processor that facilitates defining at least one resource to be accessible through the cloud. The processor is configured to identify descriptor information regarding a plurality of attributes of the resource as provided by a user. The processor is also configured to identify any particular attributes that are particular to the resource. The processor is configured to automatically generate at least one of the attributes with a plurality of different flavors.
[0007] An illustrative method of facilitating defining at least one resource to be accessible through a cloud computing system includes identifying descriptor information regarding a plurality of attributes of the resource and any particular attributes that are particular to the resource as provided by a user. At least one of the attributes is automatically generated with a plurality of different flavors, based on the identified descriptor information.
[0008] Various embodiments and their features will become apparent to those skilled in the art from the following detailed description of at least one example embodiment. The drawings that accompany the detailed description can be briefly described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 schematically illustrates an example cloud computing system including a manager device designed according to an embodiment of this invention.
[0010] FIG. 2 is a flowchart diagram summarizing an automated approach for defining a resource in the cloud computing system.
DETAILED DESCRIPTION
[0011] FIG. 1 schematically illustrates a cloud computing system 20 that includes a plurality of virtual machines 22 . Virtual machines 22 may include resources such as processors, storage, memory or network interfaces and may reside in one or more data centers (not shown for clarity). Cloud service subscribers that utilize the virtual machines 22 for data storage or computing operations are schematically shown as subscribers 24 .
[0012] A cloud manager device 30 includes data storage 32 , a processor 34 and a compiler 36 . Although the processor 34 and the compiler 36 are schematically shown separately for discussion purposes, some embodiments include a single processor or computing device that performs the functions of both. In some example embodiments, the processor 34 and the compiler 36 are configured to use the known JAVA programming language. The data storage 32 may include, for example, JAVA-based computer-executable instructions that the processor 34 carries out during one or more processes for managing the resources of the cloud computing system 20 . The data storage 32 may also include information or records regarding the resources of the cloud computing system 20 . The compiler is configured to compile data models or other programs that will be a part of or made available through the cloud computing system.
[0013] The processor 34 is configured to facilitate defining new resources in the cloud computing system 20 by at least partially automating the process. For example, the processor 34 is configured to automate at least a portion of a process of defining or introducing and exposing a new Application Programming Interface (API) in the system 20 . API developers schematically represented as users 40 can expose new APIs in a more streamlined and reliable manner by interacting with the example cloud manager device 30 .
[0014] FIG. 2 is a flowchart diagram 50 that summarizes an approach for defining a new resource or data model, such as an API. FIG. 2 is schematically divided into a right side and a left side to indicate the portions of the process that involve input or information from the user 40 and the portions that are completed by the processor 34 of the cloud manager device 30 . In this example, the processor 34 is configured to provide an interface for the user 40 to complete the user-based steps of the example process.
[0015] Consider a data model as an example resource to be defined and included in the cloud system 20 . The data model has a list of code components (e.g., classes) to be implemented, a set of Tests and Mock components to be implemented and new translator utilities to be implemented. The translator utilities are tasked, for example, with transforming business-layer requirements expressed in the data model into different flavors of cloud APIs.
[0016] A user 40 begins the process of new data model inclusion at 52 by inputting descriptor information regarding the new data model. The descriptor information indicates a plurality of attributes of the new data model in the core system. In this example, the user writes an interface having the name the user assigns to the new data model and the interface includes getters definitions for all of the properties mentioned in the previous paragraph. Example descriptor information includes a designation or name of the new data model, request/response parameters and possible error codes.
[0017] At 54 the user 40 inputs particular attribute information that indicates particular or unique attributes of the new data model. Example particular attribute information includes an indication of the cloud providers that will be supported or compatible with the new data model. When the new data model is an API, the particular attribute information will indicate the API flavors (i.e., providers) that the API will support. In this example, the user 40 maps the particular attributes (e.g., attributes that are non-standard or unique to the new data model) of the core object to each flavor data model attribute.
[0018] The particular attribute information may include special annotations that signal the compiler 36 to generate two classes. One of those classes may be referred to as a new data model class that includes all properties of the new data model, API getters and setters for these properties, constructors, builders, some other APIs for external usage (e.g., those that will be later used by JAX libraries), and a string representation of the class. The other class may be referred to as a new data model list class that is a data structure to hold the new data model classes.
[0019] At 56 the processor 34 obtains or identifies the descriptor information that was provided by the user at 52 . At 58 , the processor 34 obtains or identifies the particular attributes of the new data model that were provided by the user 40 at 54 . The processor 34 automatically generates at least one of the attributes of the new data model with a plurality of flavors at 60 based on at least the descriptor information. In this example, the processor also uses the particular attribute information when performing the automated step schematically shown at 60 .
[0020] The processor 34 is this example automatically generates all relevant artifacts and infrastructures in the core system 20 . The compiler 36 generates the classes described above as the new data model class and the new data model list class.
[0021] The descriptor information such as the request/response parameters and the error codes allows the compiler 36 to generate a class named new data model mock that is useful for test settings. That information may be included in a specially designated resource file in some examples. There are known test techniques in which the data model provides mock answers to requests from the developer user.
[0022] The compiler 36 may also use information from a special resource file provided by the user as part of the descriptor information or the particular attribute information to generate an interface named new data model translator. The new data model translator interface may be useful for translating a business layer presentation of the new data model to other flavors of presentation.
[0023] In some embodiments the processor 34 uses an annotation processing technique, such as that which is known in association with JAVA programming JAVA compilers may have known basic annotation processing capabilities. The information provided by the user 40 includes an annotation of a specific type that is interpreted by the processor 34 as an instruction to generate one or more resource classes. The processor 34 uses a known technique to automatically generate at least one of the classes with a plurality of flavors from the user-specified annotation type. Once those classes have been generated, the compiler 36 can compile the code for the new data model at 62 . If the results of the compiling at 62 and any error check or mock request processes are acceptable, then the new data model is defined for the cloud system 20 at 64 .
[0024] The way in which the cloud manager device 30 automates a significant portion of the process of defining a new resource or data model streamlines the process, reduces the amount of developer effort required and reduces the chances of error. The process summarized in FIG. 2 and described above can reduce the amount of programming or code writing required of the developer or user by approximately 90% or more.
[0025] For example, without the cloud manager device 30 performing the disclosed technique the developer would have to manually define the new data model in the core system, define the new data model for each API flavor, map all attributes of the core data model to each flavor data model, implement the new API for each flavor, map each API flavor to the core system API, define the necessary data model tests, and implement the data model tests. If the new data model has approximately ten properties, then that manual programming process would require the developer to write approximately 1000 code lines on average. The developer would have written on the order of 700 lines of code to define the class named new data model that included all its properties, API getters and setters for those properties, constructors, builders, some other APIs for external use, and string representations of the class. Another 100 lines of code would be needed for the class named new data model list. The developer would also have to write another 300 or 350 lines of code for the new data model mock class. The new data model translator interface would have required another 20 lines on average.
[0026] By contrast, with the cloud manage device 30 operating as described above the developer may only need to write an average of less than 100 lines of code for the interface. For example, approximately 60 lines of code may be sufficient to accomplish the steps schematically shown at 52 and 54 in FIG. 2 .
[0027] The preceding description is illustrative rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of the contribution to the art provided by the disclosed embodiments. The scope of legal protection can only be determined by studying the following claims. | An illustrative cloud computing manager device includes data storage and at least one processor that facilitates defining at least one resource to be accessible through the cloud. The processor is configured to identify descriptor information as provided by a user. The descriptor information indicates a plurality of attributes of the resource including any particular attributes that are particular to the resource. The processor is configured to automatically generate at least one of the attributes with a plurality of flavors based on the identified descriptor information. Automatically generating at least one of the attributes with a plurality of flavors according to the illustrative example reduces the amount of time and effort required by an individual who wishes to define the resource for the cloud computing system. | 7 |
CROSS REFERENCE TO RELATED DOCUMENTS
[0001] The present invention claims benefit of priority to U.S. Provisional Patent Application Ser. No. 60/924,705 of Sheymov, entitled “METHOD AND SYSTEM FOR NETWORK PROTECTION AGAINST CYBER ATTACKS,” filed on May 29, 2007, the entire disclosure of which is hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to system and methods for protection of communications networks, and more particularly to a system and method for improved protection of communications networks from cyber attacks, and the like.
[0004] 2. Discussion of the Background
[0005] In recent years, the continuing vulnerability of computers to hacking attacks, combined with significant increase of the number of computers using the Internet leads to the increasing potential power of cyber attacks, such as Denial-of-Service (DoS), and particularly Distributed DoS (DDoS), attacks, and the like. Protection systems and methods have been employed for addressing such attacks. However, such systems, although providing protection at the network or system level, become less effective against more powerful attacks at the levels that could be potentially achieved by the massive DDoS attacks.
SUMMARY OF THE INVENTION
[0006] Therefore, there is a need for a method, system, and device that address the above and other problems with methods and systems for protection from cyber attacks. The above and other needs are addressed by the exemplary embodiments of the present invention, which provide a method, system, and device for network protection against cyber attacks, such as Denial-of-Service (DoS), and particularly Distributed DoS (DDoS), attacks, and the like.
[0007] Accordingly, in exemplary aspects of the present invention, a method, system, and device for protecting networking computers or devices from cyber attacks are provided, including periodically changing cyber coordinates of a communications network or system; communicating the changed cyber coordinates to corresponding or reciprocal networks and/or devices so they can maintain communications; detecting a cyber attack or receiving notification from the corresponding or reciprocal networks and/or devices of a cyber attack; and changing the cyber coordinates of the network or system upon such detection or notification and communicating the changed cyber coordinates to the corresponding or reciprocal networks and/or devices. For example, such a defensive move based on changing cyber coordinates can be made periodically, deterministically or randomly, or based on an event, such as a cyber attack, and the like. Advantageously, protection against a powerful DDoS attack is shifted upstream from the target and delegated to more powerful communications devices, such as routers, and the like.
[0008] Still other aspects, features, and advantages of the present invention are readily apparent from the following detailed description, simply by illustrating a number of exemplary embodiments and implementations, including the best mode contemplated for carrying out the present invention. The present invention also is capable of other and different embodiments, and its several details can be modified in various respects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and descriptions are to be regarded as illustrative in nature, and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The embodiments of the present invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to similar elements, and in which:
[0010] FIG. 1 illustrates a background art IP version 4 (IPv4) address;
[0011] FIG. 2 illustrates an exemplary system for network protection against cyber attacks;
[0012] FIG. 3 further illustrates the exemplary system of FIG. 2 for network protection against cyber attacks; and
[0013] FIG. 4 illustrates an exemplary process for network protection against cyber attacks.
DETAILED DESCRIPTION
[0014] The present invention includes the recognition that the vulnerability of computers, for example, to the “flooding” type of Denial-of-Service (DoS), and particularly Distributed DoS (DDoS), cyber attacks, and the like, is based on a fundamental premise that the time required to process a packet in order to determine its validity is greater than time required to generate a “junk” packet used for the cyber attack. For example, in the case of the DDoS attack, this means that a large number of even relatively slow computers can generate and send more junk packets than a relatively more powerful computer can process. In other words, the defender of such a cyber attack is clearly at a computational disadvantage.
[0015] With the rapidly increasing numbers of Internet-connected computers, the computational disadvantage of a defender of cyber attacks is getting even more pronounced. This, in turn, increases vulnerability of important and even vital systems or networks, such as Systems Control And Data Acquisition (SCADA), systems or networks, and the like. Dealing with this vulnerability and the underlying computational disadvantage, by simply increasing the power of the computers performing the traditional functions, such as authentication, and the like, does not seem to be feasible.
[0016] The exemplary embodiments solve the above and other problems by employing the principle of Variable Cyber Coordinates (VCCs) to upstream networks or systems. VCCs for a transmitter and receiver employed in a protected network or system are not constant, but rather are constantly, and rapidly changing, wherein new coordinates are communicated only to authorized parties. The Cyber Coordinates can include any suitable address, such as a computer IP address or port, a telephone number, a Media Access Control (MAC) address, Ethernet Hardware Address (EHA), and the like, employed in any suitable communications system or network, and the like. By employing the principle of VCCs to upstream networks or systems, according to the exemplary embodiments, advantageously, it is possible to alleviate the problem created by cyber attacks, including a large number of DDoS attacking computers, and the like, by moving such a defensive mechanisms “upstream” and simplifying the attack detection algorithms.
[0017] Indeed, in order to launch an attack, the attacker must first know the target's cyber coordinates. Even if the attack is directed not at a single computer, but at a network, the attacker must know the network's cyber coordinates, such as the IP address of the gateway, and the like. The exemplary protection method and system provide such information only to authorized systems or networks, and deny it to all other systems or networks. In other words, the exemplary system randomizes the appropriate portion of the protected network's cyber coordinates, such as the IP addresses, and the like, and communicates them only to authorized parties, for example, in encrypted manner. Accordingly, such cyber coordinates can include IP version 4 (IPv4) addresses, as shown in FIG. 1 , IP version 6 (IPv6) addresses, or any other suitable communications protocols, and the like. Furthermore, such cyber coordinates are periodically changed and the new, currently valid cyber coordinates are communicated only to authorized parties. Such a change of cyber coordinates can be performed in any suitable manner, for example, including on a time basis (e.g., every second, minute, hour, day, week, month, year, or part thereof, etc.), deterministically or randomly, as a response to an event, such as an attack or some other occurrence, and the like.
[0018] Referring now to the drawings, FIG. 2 thereof illustrates an exemplary system 200 for network protection against cyber attacks. In FIG. 2 , the exemplary system 200 can include two or more participating Internet Service Providers (ISPs) 216 and 218 and/or telecommunications entities 222 and 224 that handle traffic for two or more protected networks or systems 206 - 212 . For example, each protected network or system 206 - 212 has an assigned IP space of x bits 214 , such as the 8 bits for an IPv4 Class C network. The networks or systems 206 - 212 typically handle these x bits 214 , for example, assigning them to the IP address space employed by the one or more computers or devices of the networks or systems 206 - 212 . The ISPs 216 and 218 , on the other hand, deliver packets to the gateways of the networks or systems 206 - 212 , and usually handle a number of networks or systems within its allocated higher y bits 220 of the IP address space. Accordingly, the ISPs 216 and 218 handle the next y bits 220 of the IP address space for its customers, i.e., the networks or systems 206 - 212 . Usually this happens with broader bandwidth than as with the bandwidth of the networks or systems 206 - 212 . The ISPs 216 and 218 receive packets destined to the networks or systems 206 - 212 from respective telecommunications entities 222 and 224 handling the backbone (e.g., Internet backbone) services for the ISPs 216 and 218 . The ISPs 216 and 218 then handle (e.g., route) the packets within their respective assigned y bits 220 . Often, these ISP-handled bits 220 number 8 or 9 bits, leaving the rest of the IP address space 226 (e.g., 15 or 16 bits for IPv4) for the telecommunications entities 222 and 224 handling the backbone services.
[0019] In an exemplary embodiment, the ISPs 216 and 218 , the telecommunications entities 222 and 224 or any other suitable entity that handles traffic for a customer network or system performs the VCC function, as described above, for example, including randomizing the cyber coordinates of the protected networks, such as their IP address spaces 226 , 220 and 214 , and the like, and distributing them on a need-to-know basis, e.g., only to authorized parties. Such functionality can be performed, for example, by controllers 228 and 330 for the respective ISPs 216 and 218 , and/or by controllers 232 and 234 for the respective telecommunications entities 222 and 224 .
[0020] In an example for the Internet, if there are two ISPs 216 and 218 protecting their customers 206 - 212 , they would inform each other of the current valid cyber coordinates of relevant customers 206 - 212 via the controllers 228 and 230 , for enabling secure communications and for preventing cyber attacks. The routers and switches of the ISPs 216 and 218 , being programmed accordingly, would direct communications traffic to the proper destinations. Similarly, two telecommunications entities 222 and 224 protecting their customers 216 - 218 , would inform each other of the current valid cyber coordinates of relevant customers 216 - 218 via the controllers 232 and 234 , for enabling secure communications and for preventing cyber attacks. The routers and switches of the telecommunications entities 222 and 224 , being programmed accordingly, would direct communications traffic to the proper destinations.
[0021] FIG. 3 further illustrates the exemplary system 200 of FIG. 2 for network protection against cyber attacks. In FIG. 3 , one or more networks or systems 302 and 304 communicate with each other via gateways 306 and 308 , and routers 310 and 312 , which provide IP addresses 316 and 318 , based on instructions from a controller 314 . When one or more of the networks or systems 302 and 304 detect a cyber attack, such as a flooding attack, and the like, the controller 314 via the routers 310 and 312 can change the IP addresses 316 and/or 318 to IP addresses 320 and/or 322 , as needed, so that the flooding packets can be dropped. In an exemplary embodiment, the IP addresses of the one or more networks or systems 302 and 304 can remain static, until a cyber attack is detected, at which time the IP addresses can be changed. In further exemplary embodiments, the IP addresses can be changed, for example, based on any suitable time, event, parameter, and the like. Examples of possible systems 302 or 306 that can detect a cyber attack can include InvisiLAN systems (e.g., as further described on the World Wide Web at invictanetworks.com/pdf/invisilantech.pdf), and the like.
[0022] Accordingly, with the exemplary system 200 , it is difficult for an attacker to launch a targeted attack without knowing the cyber coordinates of the target. FIG. 4 illustrates an exemplary process 400 for network protection against cyber attacks. In FIG. 4 , at step 402 , the cyber coordinates are updated and at step 404 traffic is routed using the updated cyber coordinates. If the attacker, however, still launches an attack without knowing the target's cyber coordinates, the attacker will “hit” the target or miss the target, as shown in step 406 . In the case of a miss, at step 408 the attacking packets can be “dropped” (e.g., by the ISP controllers, routers, switches, etc., typically capable of handling a high volume of traffic in an “upstream,” fast environment, thus protecting the customer's usually slower gateway). If, however, the attacker guesses the target network's current cyber coordinates and “hits” the target, as shown in step 406 , sensing the attack, the network's cyber coordinates can be changed (e.g., immediately or based on a predetermined number of attacks, and the like) at step 402 (e.g., via the ISP's controllers, routers, switches, etc.) and the packets now missing the target can be dropped at step 408 at the upstream location. A similar approach, as described above, can be employed within any suitable address space, such the address space of the telecommunications entities 322 and 324 , and the like.
[0023] As noted above, in an exemplary embodiment, the respective security controllers 228 - 234 of the ISPs 216 and 218 and/or the telecommunications entities 222 and 224 can update the routers, switches, and the like, of the ISPs 216 and 218 , and/or the telecommunications entities 222 and 224 , based on the changes in the protected network's cyber coordinates. In an exemplary embodiment, such controllers, switches, routers, and the like, can be programmed to drop attacking packets without notification, advantageously, in order to speed up the response time. As will be appreciated by those skilled in the relevant art(s), the exemplary embodiments can be employed at any suitable upstream and/or downstream location(s) with participation of the relevant entitie(s).
[0024] The above-described devices and subsystems of the exemplary embodiments can be accessed by or included in, for example, any suitable clients, workstations, PCs, laptop computers, PDAs, Internet appliances, handheld devices, cellular telephones, wireless devices, other devices, and the like, capable of accessing or employing the new architecture of the exemplary embodiments. The devices and subsystems of the exemplary embodiments can communicate with each other using any suitable protocol and can be implemented using one or more programmed computer systems or devices.
[0025] One or more interface mechanisms can be used with the exemplary embodiments, including, for example, Internet access, telecommunications in any suitable form (e.g., voice, modem, and the like), wireless communications media, and the like. For example, employed communications networks or links can include one or more wireless communications networks, cellular communications networks, cable communications networks, satellite communications networks, G3 communications networks, Public Switched Telephone Network (PSTNs), Packet Data Networks (PDNs), the Internet, intranets, WiMax Networks, a combination thereof, and the like.
[0026] It is to be understood that the devices and subsystems of the exemplary embodiments are for exemplary purposes, as many variations of the specific hardware used to implement the exemplary embodiments are possible, as will be appreciated by those skilled in the relevant art(s). For example, the functionality of one or more of the devices and subsystems of the exemplary embodiments can be implemented via one or more programmed computer systems or devices.
[0027] To implement such variations as well as other variations, a single computer system can be programmed to perform the special purpose functions of one or more of the devices and subsystems of the exemplary embodiments. On the other hand, two or more programmed computer systems or devices can be substituted for any one of the devices and subsystems of the exemplary embodiments. Accordingly, principles and advantages of distributed processing, such as redundancy, replication, and the like, also can be implemented, as desired, to increase the robustness and performance of the devices and subsystems of the exemplary embodiments.
[0028] The devices and subsystems of the exemplary embodiments can store information relating to various processes described herein. This information can be stored in one or more memories, such as a hard disk, optical disk, magneto-optical disk, RAM, and the like, of the devices and subsystems of the exemplary embodiments. One or more databases of the devices and subsystems of the exemplary embodiments can store the information used to implement the exemplary embodiments of the present inventions. The databases can be organized using data structures (e.g., records, tables, arrays, fields, graphs, trees, lists, and the like) included in one or more memories or storage devices listed herein. The processes described with respect to the exemplary embodiments can include appropriate data structures for storing data collected and/or generated by the processes of the devices and subsystems of the exemplary embodiments in one or more databases thereof.
[0029] All or a portion of the devices and subsystems of the exemplary embodiments can be conveniently implemented using one or more general purpose computer systems, microprocessors, digital signal processors, micro-controllers, and the like, programmed according to the teachings of the exemplary embodiments of the present inventions, as will be appreciated by those skilled in the computer and software arts. Appropriate software can be readily prepared by programmers of ordinary skill based on the teachings of the exemplary embodiments, as will be appreciated by those skilled in the software art. Further, the devices and subsystems of the exemplary embodiments can be implemented on the World Wide Web. In addition, the devices and subsystems of the exemplary embodiments can be implemented by the preparation of application-specific integrated circuits or by interconnecting an appropriate network of conventional component circuits, as will be appreciated by those skilled in the electrical art(s). Thus, the exemplary embodiments are not limited to any specific combination of hardware circuitry and/or software.
[0030] Stored on any one or on a combination of computer readable media, the exemplary embodiments of the present inventions can include software for controlling the devices and subsystems of the exemplary embodiments, for driving the devices and subsystems of the exemplary embodiments, for enabling the devices and subsystems of the exemplary embodiments to interact with a human user, and the like. Such software can include, but is not limited to, device drivers, firmware, operating systems, development tools, applications software, and the like. Such computer readable media further can include the computer program product of an embodiment of the present inventions for performing all or a portion (if processing is distributed) of the processing performed in implementing the inventions. Computer code devices of the exemplary embodiments of the present inventions can include any suitable interpretable or executable code mechanism, including but not limited to scripts, interpretable programs, dynamic link libraries (DLLs), Java classes and applets, complete executable programs, Common Object Request Broker Architecture (CORBA) objects, and the like. Moreover, parts of the processing of the exemplary embodiments of the present inventions can be distributed for better performance, reliability, cost, and the like.
[0031] As stated above, the devices and subsystems of the exemplary embodiments can include computer readable medium or memories for holding instructions programmed according to the teachings of the present inventions and for holding data structures, tables, records, and/or other data described herein. Computer readable medium can include any suitable medium that participates in providing instructions to a processor for execution. Such a medium can take many forms, including but not limited to, non-volatile media, volatile media, transmission media, and the like. Non-volatile media can include, for example, optical or magnetic disks, magneto-optical disks, and the like. Volatile media can include dynamic memories, and the like. Transmission media can include coaxial cables, copper wire, fiber optics, and the like. Transmission media also can take the form of acoustic, optical, electromagnetic waves, and the like, such as those generated during radio frequency (RF) communications, infrared (IR) data communications, and the like. Common forms of computer-readable media can include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other suitable magnetic medium, a CD-ROM, CDRW, DVD, any other suitable optical medium, punch cards, paper tape, optical mark sheets, any other suitable physical medium with patterns of holes or other optically recognizable indicia, a RAM, a PROM, an EPROM, a FLASH-EPROM, any other suitable memory chip or cartridge, a carrier wave or any other suitable medium from which a computer can read.
[0032] While the present inventions have been described in connection with a number of exemplary embodiments, and implementations, the present inventions are not so limited, but rather cover various modifications, and equivalent arrangements, which fall within the purview of claims of the present invention. | A method, system, and device for protecting networking computers or devices from cyber attacks, including periodically changing cyber coordinates of a communications network or system; communicating the changed cyber coordinates to corresponding or reciprocal networks and/or devices so they can maintain communications; detecting a cyber attack or receiving notification from the corresponding or reciprocal networks and/or devices of a cyber attack; and changing the cyber coordinates of the network or system upon such detection or notification and communicating the changed cyber coordinates to the corresponding or reciprocal networks and/or devices. | 7 |
RELATED APPLICATION
A commonly-owned patent application Ser. No. 10/866,630, filed Jun. 14, 2004 DISPOSABLE ELECTROSURGICAL HANDPIECE FOR TREATING TISSUE now U.S. Pat. No. 7,101,370.
This invention relates to a laser surgical instrument in which the end of the active fiber or other beam transmitting device from which the laser beam radiation source emanates is positionable by the surgeon.
BACKGROUND OF THE INVENTION
Our prior U.S. Pat. No. 6,231,571, describes a novel electrosurgical handpiece for treating tissue in a surgical procedure commonly known as minimally invasive surgery (MIS). Among the features described and claimed in the prior application is an electrosurgical handpiece that can be used in MIS and reduces the danger of excessive heat causing possible patient harm. This is achieved in one embodiment by an electrosurgical handpiece that is bipolar in operation and that is configured for use in MIS. The bipolar operation confines the electrosurgical currents to a small active region between the active ends of the bipolar electrode and thus reduces the possibility that excessive heat will be developed that can damage patient tissue. Moreover, the position of the active region can be controlled to avoid patient tissue that may be more sensitive to excessive heat. Preferably, the handpiece is provided with a dual compartment insulated elongated tube, each of the compartments serving to house one of the two wires of the bipolar electrodes. The electrode for MIS use is preferably constructed with a flexible end controllable by the surgeon so as to allow the surgeon to manipulate the end as desired during the surgical procedure. In a preferred embodiment, the flexible end is achieved by weakening at the end the housing for the electrode, and providing a pull string or wire connected to the weakened housing end and with a mechanism at the opposite end for the surgeon to pull the string or wire to flex the housing end to the desired position. This feature allows the surgeon to position the active electrode end at the optimum location for treating, say, a herniated disk to remove undesired regions and to provide controlled heat to shrink the tissue during surgery. In FIGS. 3–7 of the prior application, a suitable bipolar electrode is described, which comprises a pair of rounded electrodes with spaced flat sides separated by an insulating layer. FIGS. 8–10 illustrate a suitable unipolar electrode construction of the flexible end handpiece. FIG. 12 illustrates how such an electrode can be used for the reduction of herniated disks in a laparoscopic procedure. FIG. 19 shows a construction that combines both a bipolar and a unipolar electrode either of which can be selected by the surgeon for use with the procedure. FIG. 20 shows a scissors end that can be constructed as a bipolar electrode for certain purposes. Other constructions to provide easier flexing of the handpiece end, as well as the use of memory metals to control the position of the extended electrode, are also discussed.
One limitation of the handpiece constructions described in these prior applications is the relatively high fabrication costs, which deters single uses of the handpiece by the surgeon.
Nowadays, surgeons prefer if feasible disposable instruments that can be discarded after one use and no longer need sterilization and sterile packaging for future uses.
The referenced co-pending patent application describes a relatively inexpensive handpiece construction for such instruments with flexible tips. Thus, the handpiece can be made so as to be disposable if so desired.
The present application is concerned with surgical lasers, constructed in the form of a gun for MIS procedures. A drawback of known constructions is that the active laser tip from which the laser radiation beam emanates is typically in a fixed position, or in some more modern versions can be extended forward but typically only in a straight line. This can present problems for the surgeon user as it may not be easy to reach with the laser beam surgical sites located behind other tissues or not positioned in-line with the typical cannula through which the laser fiber is introduced into the patient's tissue.
SUMMARY OF THE INVENTION
The present invention hereby incorporates by reference the total contents of the co-pending prior application Ser. No. 10/866,630 and U.S. Pat. No. 6,231,571. The present invention describes and claims among other things a handpiece construction for a laser probe instrument with a position-controllable tip. Since the present application otherwise makes use of some of the same teachings of the prior application and patent, it was felt unnecessary to repeat in the body of this specification many of the details present in the contents of the prior application and patent. The present description will be confined solely to the modifications in the handpiece construction that allow for construction of a laser probe with a position-controllable active tip. A further feature is an inexpensive construction that allows for disposability if desired. Another feature is a laser probe with a position-controllable tip combined with an electrosurgical electrode also with a position-controllable end whereby the operating surgeon can use with the same handpiece either surgical mode if desired during a particular surgical procedure. More specifically, the construction of the present invention that incorporates an electrosurgical electrode can provide both bipolar and unipolar operation separately or in the same handpiece, and can use the same constructions described in the prior application and patent for providing the extendable and retractable straight and/or curved active electrode tips, as well as many of the details for providing a flexible end or a straight end with a curved extendable electrode, including use in the various medical procedures described in the prior applications and known to others in this art in which electrosurgical currents are used to modulate patient tissue, meaning to cut, ablate, shrink, and/or coagulate tissue. For more details, the reader is directed to the prior application, the referenced patent, and to the following publications dealing with laser surgery, all of which are hereby incorporated by reference:
1. The Practice of Minimally Invasive Spinal Technique, edited by Savitz, Chiu, and Yeung, 1 st Ed., 2000, and in particular Ch. 10 directed to Percutaneous Laser Discectomy, Ch. 15 directed to Cervical Endoscopic Discectomy With Laser ThermoDiskoplasty, and Ch. 42, Endoscopic Laser Foraminoplasty.
2. Journal of Clinical Laser Medicine And Surgery, Vol. 13, No. 1, 1995, Pgs. 27–31, which describes a side firing Holmium:YAG Laser fiber intended to reach sites not easily reached by an in-line needle fiber.
3. Surgical Application Of Lasers, by Dixon, Year Book Medical Publishers, 1983.
4. CO 2 Laser Surgery, By Kaplan and Giler, Springer-Verlag, 1984.
5. Endoscopic Laser Surgery of the Upper Aerodigestive Tract, by Steiner and Ambrosch, Thieme Stuttgart, 2000.
The handpiece constructions of the present improvement are focused for the most part at the gun or handle end of the handpiece, meaning the part of the handpiece held in the hand of the surgeon and operable by the surgeon to extend and retract the active fiber tip. It will be understood that any and all kinds of beam-generating lasers can be connected to the novel handpiece construction of the invention by means of conventional optical fibers, unimode or multimode, or by means of thin transmission probes. The thin optical fibers that are typically soft and flexible, in the preferred embodiment, can be directly incorporated permanently or removably in the novel handpiece construction of the invention, essentially in a similar manner to that of the electrosurgical electrode in the copending application. Moreover, any and all kinds of laser fibers of various sizes and lengths appropriate for the surgical procedure contemplated can be employed. Hence, the present description will focus on the gun construction which accommodates the active fiber, and the means for extending and retracting the active fiber end, and the construction that allows the fiber to be combined with an electrosurgical electrode for greater versatility.
In a preferred embodiment according to the invention, the handle end of the handpiece is constructed preferably of known plastics, such as ABS, and thus can be, for example, molded in several parts and simply assembled by being force-fitted and/or adhered together by suitable adhesives, or snapped together as is well known in the art for assembling plastic members. Preferably, all parts of the handle end apart from some metal parts, optionally a metal spring, and the electrode assembly if included can be made of inexpensive plastic.
In accordance with another preferred embodiment, the fiber tip position is controlled by associating it with a wire, tube, or other elongated member constituted of known shaped memory material, typically metal but can also be of well known plastics. The elongated member constituted of shaped memory material is preset or pre-configured to a specific configuration and then mounted into a tubular support member in its retracted position. When the fiber with its associated shaped memory member is extended, the shaped memory member assumes its preset configuration forcing the flexible fiber to which it is connected or which houses it to also assume the same configuration. In a further preferred embodiment, the tubular support member is straight, and the shaped memory member is pre-curved, so that the extended soft flexible fiber assumes the same curvature when extended from the tubular support member.
In a further preferred embodiment, the handle is a one-piece member connected across slidable body parts configured such that squeezing of the handle by the surgeon causes the body parts to come together which action causes the active end of the fiber to extend out of the tubular support member.
In accordance with still another preferred embodiment, the handpiece combines with the position-controllable optical fiber an electrosurgical electrode, also extendable into a controlled position, with either the optical fiber or the electrode being selectively extendable by the user. Each of the optical fiber or the electrode are connected respectively to laser beam generating apparatus and to an electrosurgical current generator, and thus either of the two instruments can be selected and operated by the surgeon from the same handpiece during the same or different procedures.
The constructions of the invention will provide the same important benefits as obtained with other surgical laser and electrosurgical devices not only for MIS of herniated disks but also for other MIS procedures where controlled tip position and/or controlled heat generation is of importance as described in the prior applications and publications, as well as for general surgical procedures where volumetric reduction of tissue is desirable.
While the invention of the handpiece of the invention has focused on low-cost fabrication allowing disposability or one-time use, it will be understood by those skilled in this art that the same handpiece can also be reusable if the practitioner so desires, by appropriate sterilization after each use. Most forms of sterilization can be used by an appropriate choice of handpiece materials, such as high-temperature plastics, but gas sterilization as is well known in this art can also be used if heat-sensitive material may be present.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention, like reference numerals designating the same or similarly functioning parts.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a vertical cross-sectional view of one form of surgical laser handpiece in accordance with the invention with the working end shown in its retracted position;
FIG. 2 is an enlarged view of the working end of the surgical laser handpiece illustrated in FIG. 1 ;
FIG. 3 is a vertical cross-sectional view of the surgical laser handpiece of FIG. 1 but with the working end with the optical fiber extended into operating position;
FIG. 4 is an enlarged view of the working end of the surgical laser handpiece illustrated in FIG. 3 ;
FIG. 4A shows a variation in which the memory metal is in the form of a strip;
FIG. 5 is an exploded view of the surgical laser handpiece of FIG. 1 ;
FIG. 6 is a side view of one form of surgical handpiece in accordance with the invention combining a laser with an electrosurgical electrode;
FIG. 7 is a vertical cross-sectional view of the surgical handpiece of FIG. 6 but with the working end with the optical fiber extended into operating position;
FIG. 8 is a vertical cross-sectional view of the surgical handpiece of FIG. 1 but with the working end with the electrosurgical electrode extended into operating position;
FIG. 9 is a perspective view of the surgical handpiece of FIG. 6 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The reader is directed to the referenced prior application and patent for a more detailed description of the prior applications which will assist in understanding the improvements offered by the present application.
In the present application, the handpiece configuration remains essentially similar to the prior configurations. It can comprise the use of a pulling wire to flex a flexible end of an outer tube housing for the handpiece while simultaneously extending the fiber or electrode from the end of the outer tube. Or, preferably, the outer tube end is not flexible, but the fiber or electrode distal end is constituted of memory metal or has been given a pre-bent contour such that, when extended from its outer tube housing, it assumes a preset curved or straight position that allows the surgeon to reach with the active end of the electrode patient sites behind, say, other tissues more easily. Other electrode constructions that allow the surgeon to extend an active electrode end from a surgical elongated tubular member and cause the active end to assume straight or curved configurations can also be alternative constructions in accordance with the present invention. When both a laser fiber and electrosurgical electrode are combined, preferably a dual compartment tubular housing is employed, with one of the compartments housing the laser fiber with associated shaped memory member, and the other compartment housing the electrosurgical electrode. Or, alternatively, side-by-side separate tubular members can be provided for each.
FIG. 1 shows one form of handpiece 10 for use with one form of a laser surgical instrument of the invention. It comprises a squeezable handle 12 of elastic material connected to and across front 14 and rear 16 main slideable body parts with the front body part 14 enclosing an elongated outer tubular housing 18 from whose distal end 20 ( FIG. 2 ) an elongated inner tube 22 constituted of shaped memory material in turn housing a typical optical fiber 24 whose active tip 25 from which the radiation beam emanates can be extended and retracted when the handle 12 is squeezed or released, respectively. The rear body part 16 comprises a generally cylindrical member 30 with a middle reduced diameter section 32 and a distal reduced diameter threaded section 34 . One of two handle mounts 36 is threaded onto the distal section 34 . The distal section 34 at its right end is slotted and forms with a threaded collet 38 a releasable lock for the active fiber. The front body part 14 comprises a nosepiece 40 on which is mounted the second handle mount 42 . Those two handle mounts, as will be evident from the exploded view of FIG. 5 , are mounted by way of screws 44 to the handle 12 . Mounted below the body parts are a tubular slide support 46 which slides over a screw 48 whose right end is threaded and screwed into a threaded hole 50 in the second handle mount 42 after passing through an enlarged bore 52 in the first handle mount 36 . As the handle 12 is squeezed, the tubular slide support 46 carrying the rear body part 16 , driven by the slideable left handle mount 36 , slides to the right in FIG. 1 over the screw 48 connected to the right handle mount 42 . This construction, of relatively low cost, provides a smooth stable sliding action.
At the distal end of the assembly 10 , the outer tube 18 , for example, of metal or stiff plastic, is mounted as by a suitable adhesive into a front bore of the nosepiece 40 and extends forwardly a considerable distance, for example, about 12–20 inches. Slidable within that outer tube 18 is a thin tube 22 ( FIG. 5 ) of memory material enclosing a standard optical fiber 24 (not shown in FIG. 5 ). One example of a shaped memory material, which is not to be deemed limiting, is NITINOL, a nickel-titanium alloy. The memory tube 22 extends through the nosepiece 40 , through the collet 38 and rear cylindrical member 30 and exits the assembly at the left rear. From its termination extends the fiber 24 which ultimately can be connected to a conventional laser system which, as an example, may be a HO-YAG laser source beam generator 64 ( FIG. 6 ). With the collet 38 loosened, the entire tube 22 of memory material and its inner fiber 24 can be removed from the left back end of the assembly 10 . When the collet 38 is tightened, the slitted end 34 grips the tube 22 of memory material and its inner fiber and the latter is fixed to the rear body part 16 . As will be evident from this description, when the handle 12 is squeezed, the rear body part 16 moves to the right pushing and extending the tube 22 of memory material and its inner fiber 24 out of the distal end 20 of the outer tube 18 . This action is illustrated in FIG. 4 . Typically, as explained earlier, the tube 18 of the gun is preferably straight but the tube 22 of memory material has been pre-configured to assume a curved position. Thus, when the tube 22 of memory material and its inner fiber 24 are extended, the tube 22 curves upward as shown in FIG. 4 and forces the very flexible inner fiber 24 to assume the same curved shape. FIG. 4 is an enlarged view showing this action. When the handle is released, the biasing force exerted by its elastic nature causes the two handle halves to separate retracting the tube 22 of memory material and its inner fiber 24 back within the stiff outer tube 18 which forces the tube 22 of memory material into a straight position. The exploded view of FIG. 5 illustrates how the various parts can be assembled to form the completed handpiece 10 of FIG. 1 .
The invention is not limited to enclosing the flexible fiber in a tube of memory material. The latter can be replaced by a strip of memory material to which the fiber is attached so it is forced to adopt the shape assumed by the memory strip. This variation is shown in enlarged form in FIG. 4A with the memory strip shown at 66 and the fiber at 68 .
In FIG. 1 , a sleeve 70 is mounted on the front body part 14 and merely serves to keep the interior clean if exposed to liquid or other debris. Loosening of the collet 38 allows the laser fiber to be removed from the handpiece and replaced by another fiber if desired.
If desired, the resilient handle 12 can be replaced by a flexible handle supplied with a resilent band as described in the copending application, or by some other equivalent construction providing a biasing force. In the embodiment shown, the collet 38 can be permanently secured to the rear body part 16 so that the fiber is not changeable, but the preferred handpiece construction of the invention allows for a changeable memory member with a different fiber if desired.
The assembly can be made permanent by force-fitting together of the parts or by using adhesives between the assembled parts. A preferred way is to slightly taper the various parts that telescope together of a suitable plastic, apply as by brushing to the eternal surface of the inner fitting part a suitable solvent for the plastic, and force the parts together. The solvent slightly dissolves a thin surface layer of the plastic and when the solvent evaporates, the two contacted parts are essentially fused together permanently. For a removable fiber, the fiber with its memory member can be added later and configured so that it moves freely inside the aligned bores. With a screwed nose piece, the fiber can be locked into place for use. Or if the fiber is to be made a permanent part of the handpiece, then it can be provided with an enlarged stop at its internal terminating end to prevent inadvertent removal.
Once the surgeon has positioned the tubular working end of the handpiece inside the typical cannula with respect to the tissue to be operated on, he or she then activates the laser apparatus causing emission of a laser beam from the active tip capable of causing ablation, shrinkage, or excision of tissue, or cauterization of a blood vessel in the usual way. Other usable mechanical or electrical structures following the teachings of the prior applications will be appreciated by those skilled in this art. As with the embodiments of the prior application, the tube 18 can be insulating if desired.
In all embodiments, the tubular housing 18 can be plastic, such as ABS or DELRIN, or of insulated relatively stiff metal that will not bend except where desired. For example, the tube outside diameter can be typically about 0.04–0.1 inches. For the application of shrinking herniated tissue via a cannula, the tubular housing is typically about 15–20 inches long. It will also be noted that the features set forth in commonly owned U.S. Pat. Nos. 6,652,514 and 6,712,813, namely incorporating the handpiece with the flexible tip of the invention into the intelligent operating-mode selection system of the earlier patent, and/or as a procedure-dedicated handpiece of the later patent, can also be readily implemented by those skilled in this art following the teachings of those patents.
The automatic retraction of the fiber may be caused by an internal compression spring. Alternatively, the plastic handle can be configured such that it has built-in resilience which tends to return it to its open position as shown in FIG. 1 in the preferred embodiment. As a further alternative, a resilient leaf or helical spring, for example, of metal or fiberglass, can be fitted inside of or between the handle sides to provide an outward bias force tending to maintain the handle sides in their open position. However, it is preferred that the handle itself be electrically-insulating to prevent any chance of an electric shock to the surgeon or the patient if an electrosurgical electrode is added.
An important advantage of the construction described is its inexpensive construction and fabrication thus allowing handpiece disposability after one use. However, as explained above, the handpiece of the invention can also be reused if desired by appropriate sterilization after each use. A further advantage with the use of an elongated tubular member constituted of shaped memory material is that the latter also serves a protective function of the fiber end when extended.
In the preferred embodiment, the position of the active laser end is controlled by housing the flexible fiber in an elongated tubular member constituted of a known shaped memory material, and thus when the shaped memory metal tube is extended, it assumes its pre-configured shape thereby forcing the flexible fiber inside of it to assume the same shape. Alternatively, the elongated member constituted of shaped memory material can be formed by a wire or strip that is attached along its length, at least where it is extended and retracted from the outer tube, to the fiber. Again, the same result is obtained as with the tubular inner member as the preset wire when freed from the outer tube assumes its memorized curved shape and forces the fiber to follow. It will also be appreciated that rotation of the handpiece will cause the extended fiber tip to trace a circle allowing access to various possible surgical sites from the same positioned cannula or working channel of an endoscope. While the preferred embodiment employs a fiber whose radiation beam is in-line with the axis of the fiber, it is of course possible to bevel the fiber end so that the radiation beam exits laterally to the fiber axis to produce the so-called side-firing tips. While the preferred embodiment shows a straight outer tube in which the extended fiber assumes a curved shape, it is also possible for the extended fiber to extend in-line with the outer tube axis if so desired, or that the end of the outer tube is curved and the extended fiber extends in-line from the curved outer tube or provides additional or different curvature from the outer tube. It is also possible following the teachings herein disclosed for the outer tube to have a bayonet shape. The bayonet shape, as is known in other contexts, provides improved surgeon visibility of the active laser tip at the surgical site.
It will also be evident to those skilled in this art that an ON-OFF switch can be added to the handpiece and wires provided to send a control signal back to the laser system unit to turn the laser generator on or off under control of the surgeon operating the switches on the handpiece. Further, our U.S. Pat. Nos. 6,652,514 and 6,712,813 describe, respectively, an intelligent selection system for an electrosurgical instrument and a procedure-dedicated electrosurgical handpiece, the contents of which are hereby incorporated by reference. In the former, fingerswitches are added to the handpiece and impedances such that when a fingerswitch is activated, a control signal current determined by the impedance is transmitted back to the electrosurgical unit, which, as one example, incorporates a microcontroller and a suitable memory or computer routines that are selected by the incoming control signal current and thus sets in the electrosurgical unit the operating electrosurgical mode and if desired operating conditions such as power level and on-time duration that are specific to the procedure that the surgeon intends to carry out. The latter adds to the former the teaching of a handpiece incorporating a specific impedance and also provided with an integral electrode dedicated to a particular procedure. These teachings are easily incorporated in the laser instrument of the present invention. For example, one or more fingerswitches can be added to the handpiece and a suitable impedance incorporated such that, activation of a handpiece fingerswitch generates a control signal that sets an operating mode of the laser system unit, such as the laser pulse mode (single or multi-pulse), in a similar manner to that described in these referenced patents.
One of the features of the present invention is that the handpiece of the invention can easily be modified to incorporate an electrosurgical electrode into a handpiece containing a laser fiber. This is in part based on the teachings of U.S. Pat. No. 6,231,571, herein incorporated, and in particular, FIGS. 13–19. In those figures of the patent, embodiments are described that incorporate both a unipolar and a bipolar electrosurgical electrode into the same handpiece, either of which can be selectively extended by the user-surgeon during a surgical procedure. In that embodiment, squeezing the handle extends the bipolar electrode from its tubular housing, as the extension mechanism is similar to that described in connection with the other embodiments. When a unipolar electrode is to be selected, an auxiliary extension mechanism involving a slide on the side of the outer tube can be activated by the user's thumb. The slide is connected to the unipolar electrode, which then is extended forwardly into operating position. It is also obvious that the operation can be reversed, with the handle operatively connected to the unipolar electrode and the slide operatively connected to the bipolar electrode. A similar principle can be employed to combine in the same handpiece a laser and an electrosurgical electrode or a laser with both a unipolar and a bipolar electrode as illustrated in FIGS. 6–8 .
FIGS. 6–9 show one form of construction suitable for a multi-function (laser surgery and electrosurgery) surgical handpiece in accordance with the invention. In this preferred embodiment, a dual-compartment structure is employed. If a laser fiber with a single electrosurgical electrode only is incorporated, then only a two-side-by-side compartment structure is needed; if in addition a second electrosurgical electrode is incorporated, then a third compartment would be required. In its simplest form, the handle could be operatively connected to operate, by means of the handle, say, the laser fiber in a first compartment, a first slide on one side would be operatively connected to operate, say, the bipolar electrode in a second compartment, and a second slide on the opposite side would be operatively connected to operate, say, the unipolar electrode in a third compartment. The active components can be rearranged so that the different modalities are otherwise arranged. Preferably, the fiber connections and electrical connections are made at the rear as illustrated in FIG. 6 . However, it is also possible to bring in the laser connection from the rear and the electrical connections from the side, as it may be simpler to bring in the electrical wires for the electrode(s) from the side.
A preferred embodiment is illustrated in FIG. 6 , wherein the construction and operating mechanism for extending and retracting the laser fiber is the same as in FIG. 1 (the same reference numerals are thus used). Thus, the handpiece comprises a squeezable handle 12 connected to and across front 14 and rear 16 main relatively slideable body parts enclosing an elongated outer tubular housing 18 from whose distal end 20 an elongated inner tube constituted of shaped memory material 22 in turn housing a typical optical fiber 24 whose active tip 25 from which the radiation beam emanates can be extended and retracted when the handle 12 is squeezed or released, respectively. At the left end a adjustable collet 38 mounted on the rear body part 16 and when tightened locks the memory tube and flexible optical fiber to its outer tube housing 18 . The exiting fiber at the left end can be ultimately connected to a conventional laser system which, as an example, may be a HO-YAG laser source 64 .
The outer 18 and inner 22 tubular members for the fiber 24 can be as shown as a separate tubular system, or alternatively occupy one compartment of a multi-compartmented exterior tubular member similar to the constructions shown in the referenced patents. The front body part 14 is fixed, and the rear main body part 16 is connected to the inner tube 22 .
A separate structure is provided for the electrosurgical electrode. It includes a bottom part 72 of the enlarged front body part 14 , a slide 74 (not shown in FIG. 6 but shown in FIG. 9 ) is connected to the outside of a slideable cylinder 76 having an internal bore containing a compression spring 78 . The cylinder 76 slides on a rearwardly projecting part 80 of the fixed part 72 . A rotatable collet 82 mounted at the rear of the cylinder 76 , when tightened in the usual way, grips a tube 84 housing an inner tube 86 containing a unipolar electrosurgical electrode 88 inside a tube 90 of memory metal. The electrosurgical electrode may be a unipolar or bipolar electrode. Alternatively, still another tubular member can be added to the assembly for housing the other of the unipolar or bipolar electrodes, and the latter in turn activated by a second slide connected to the added electrode.
The slide mechanism is operated by the thumb of the surgeon moving the slide 74 to the right of FIG. 9 . This causes the cylinder 76 to move to the right against the bias of the spring 78 and causes the gripped tube 90 and electrode 88 to be extended from the outer tubular member 84 , and the electrode will assume the pre-set shape of the memory tube 90 , as shown in FIG. 8 . When the thumb pressure is released, the spring forces the cylinder 76 back to its rear starting position and causes the electrode to retract. A second slide mechanism if provided can be constructed on the same principles as the first slide to operate in the same way. Separate energizing conducting wires for the two electrodes can be provided extending out from the rear or sides of the multi-compartmented housing. The wires, which are typically flexible, where connected to their respective electrodes, can be provided with some slack so that extension of an electrode, which typically only extends about 1–2 inches, will not cause undue strain on the wire itself. If desired the use of strain-relief wire mounts can be added. Such multi-modality handpieces can be used in procedures where a cannula in unnecessary, or with a somewhat larger cannula to house a larger multi-compartmented exterior tubular member.
FIG. 7 shows the instrument of FIG. 9 with the handle squeezed to extend the fiber, whereas FIG. 8 shows the instrument of FIG. 9 with the slide actuated to extend the electrosurgical electrode.
As in the earlier applications for the electrosurgical handpiece, two electrically-insulated wires are needed for the bipolar electrode, but for a unipolar handpiece, only a single wire may be necessary connected to a typical unipolar electrode such as a ball, point, rod, or loop, as examples. The means for making contact between the wire ends and the electrosurgical electrode can be the same means described in the copending patent application. The electrode where it exits from the assembly can be connected in the usual way to conventional electrosurgical apparatus, an example of which is given in the referenced patent and application.
As in the previous applications directed to electrosurgery, it is preferred that for the embodiment containing the electrosurgical electrode, the electrosurgical currents be in the MHz range, preferably 34 MHz, sometimes referred to as radio frequency electrosurgery, as it is found that best results are obtained with this range of electrosurgical currents.
As used herein, by “axial” is meant parallel to the long axis of the fiber or electrode (horizontal in FIGS. 1 and 6 ). By “lateral” is meant transverse to the long axis of the fiber or electrode.
While the invention has been described in connection with preferred embodiments, it will be understood that modifications thereof within the principles outlined above will be evident to those skilled in the art and thus the invention is not limited to the preferred embodiments but is intended to encompass such modifications. | A disposable or reusable surgical laser handpiece having an extendable and retractable active laser fiber tip and housed in a body comprising an actuating handle for use in various surgical laser procedures. The fiber tip when extended can be given a specific configuration by associating the fiber with a shaped memory member. The housing can also be constructed to incorporate bipolar or unipolar electrosurgical electrodes. | 0 |
This application is a continuation of application Ser. No. 08/343,614, filed Nov. 22, 1994, which is a continuation application of Ser. No. 08/208,805, filed Mar. 9, 1994, which is a continuation application of Ser. No. 08/000,792, filed Jan. 4, 1993, which is a continuation application of Ser. No. 07/695,802 filed May 3, 1991, all abandoned.
BACKGROUND OF THE INVENTION
The invention relates generally to a method of and an apparatus for removing volatile and semi-volatile contaminants from a contaminated site in the earth and, more particularly, relates to a method of and an apparatus for removing volatile and semi-volatile contaminants from the earth by heating a portion of the contaminated earth by electromagnetic energy. The heated contaminated site is swept by air in a controlled manner to avoid interrupting the electromagnetic heating, to avoid fugitive emissions of contaminants to the atmosphere and to provide an air-contaminant vapor-water vapor mixture having a relatively high concentration of contaminant vapor easily adsorbed by a carbon bed or the like. An economic and efficient removal of the contaminants is achieved.
In recent years the public and the government have come to recognize that small amounts of various organic materials that have been spilled or improperly disposed of at various sites are environmental hazards and must be cleaned up. In the past, cleanup operations required that the entire site be excavated and that the soil and other site materials contaminated with unwanted or dangerous materials, such as hydrocarbons, halocarbons, and the like, had to have substantially all the contaminating material removed from them. In a typical prior art decontamination method, the entire site is excavated and all the excavated site materials are burned in a portable incinerator. Such a method is costly if the site is extensive, and may be impractical due to the large volume of contaminated soil if the contaminated site is deep.
Another method, as disclosed in U.S. Pat. No. 4,670,634 to Bridges, et al., treats a contaminated site by heating it with radio frequency energy. A plurality of fringing field electrodes is electrically excited by a radio frequency current to produce a bound, fringing, time-varying electric field that dielectrically heats portions of the contaminated site located below the electrodes. Volatile contaminants trapped in the site are volatilized or distilled and create sufficient autogenous pressure that they can be vented from the site surface into a chamber confined by a tent-like vapor barrier over the site. As may best be seen in FIGS. 1 and 3 of Bridges, et al., vapor exiting the ground is collected beneath the tent-like vapor barrier and carried by a vapor and gas collection line 34 to an external gas-liquid separator. In an alternative embodiment, as may best be seen in FIG. 7 of Bridges, et al., gravel is placed on the site surface in two layers. A plurality of gas and vapor collection ducts 68 is buried in the lower level of the gravel for carrying evolved contaminant vapors away from the site to treatment apparatus. The lower gravel layer, with the collection ducts positioned therein, is covered by an impermeable vapor barrier and the impermeable vapor barrier is overlaid by the upper gravel layer. The fringing field electrodes are positioned above the upper gravel layer substantially free from contact with it.
A similar system is disclosed in H. Der, et al., "In Situ Radio Frequency Heating Process for Decontamination of Soil," Solving Hazardous Waste Problems, presented at the 191st Meeting of the American Chemical Society, Apr. 18, 1986. The Dev, et al. system includes fringing field electrodes covered by the tent-like vapor barrier. Der, et al. also disclose that a site may be heated by radio frequency energy supplied by tubular vertical electrodes in boreholes, or by horizontal electrodes positioned above the surface of the soil to be heated. The electrodes are energized by a source of electrical energy producing an electric current having a frequency in the range of 6 MHz to 13 MHz. Transport of vaporized volatile contaminant to the collection region from the site is effected solely by the vapor pressure of the heated volatile contaminant and evolved water vapor. Dev, et al. disclose experimentation with small batches of sandy soil to determine the feasibility of removing chlorinated hydrocarbons, in particular tetrachloroethylene, from them. Dev et al. also discuss vacuum extraction technologies as alternatives for the Dev et al. system. The vacuum extraction technologies are directed to removing volatile contaminants from soil by drawing a vacuum inside or adjacent to the contaminated region of the site so that the contaminant is drawn out of the site.
In the methods described by Bridges, et al. and Dev, et al., it is necessary to heat the soil to a temperature sufficient to increase the vapor pressure of the contaminants to cause their volatilization and to overcome the pressure drop needed for movement of the volatilized contaminants through the contaminated earth to the collection region. Because the collection region is near the surface, it is not practical to draw a vacuum at the collection region greater than one inch on water gauge. As a result, pressures higher than atmospheric are generated in portions of the heated soil to overcome the pressure drop for movement of the volatilized contaminants from the region of volatilization to the collection region. Generation of such superatmospheric pressures may result in fugitive emissions of the volatilized contaminants from the earth's surface in regions not covered by the vapor-barrier, thereby contributing to air pollution.
As discussed above, vacuum or reduced pressure is used for in situ remediation of soils contaminated with hydrocarbons, such as solvents or fuels and is generally referred to as vacuum extraction technology, sometimes abbreviated as VET. A number of workers in the art are offering commercial remediation services based on this technology. The commercial methods and apparatus generally involve drilling a well into the vadose zone of the earth followed by the application of vacuum to volatilize and collect the contaminants. Multiple wells are sometimes used for large contaminated sites. Injection wells are used in combination with recovery wells in alternative methods. A common drawback is the inability to treat economically sites containing relatively less volatile materials, such as jet fuels.
U.S. Pat. No. 4,183,407 to Knopik discloses an underground exhaust system for removing vapors. The system employs a number of underground conduits inserted through an excavated shaft. A plurality of elongated and perforated collection elements connected to the conduits are buried in the contaminated site. An exhaust system for drawing gasoline vapors from the contaminated site is connected to the other end of the conduit. Such a system involves expensive shaft preparation, drilling of radial holes for conduits, and disposal of the excavated soil.
Visser and Malot U.S. Pat. Nos. 4,593,760 and 4,660,639 disclose vacuum extraction technology and well completion systems for decontamination of the vadose zone and for recovery of liquids trickling through the vadose zone. Their system effects vaporization, at ambient temperature, of the contaminants present in the vadose zone by applying sufficient vacuum. It is feasible to draw a vacuum sufficient to evaporate light solvents or volatiles, such as carbon tetrachloride or benzene, at ambient temperature. However, for most decontamination applications involving soils containing semi-volatiles or high boiling materials, such as jet fuels, the amount of vacuum needed for significant evaporation is relatively high. Visser and Malot depend upon putting a conduit in a larger borehole and completing it in such a way that the lower portion is filled with an permeable medium and the upper portion is filled with an impermeable medium. From practical considerations, the borehole cannot be larger than the conduit. This produces an annulus of limited dimensions.
Agrelot, Malot and Visser, Vacuum: Defense System For Ground Water VOC Contamination disclose use of a nearly complete vacuum, 29.9 inches of mercury, for sites contaminated with a light solvent such as carbon tetrachloride. Use of such a high vacuum, however, results in intrusion of large quantities of air through the soil and significant dilution of the contaminant vapor with air. The concentration of carbon tetrachloride in the air-carbon tetrachloride effluent is only about 2.7 per cent based upon the data of Agrelot, et al. Since carbon tetrachloride has a vapor pressure of over 100 millimeters of mercury at 25° C. if no air bypass has occurred, the concentration of carbon tetrachloride in the effluent is expected to be about 13 per cent based upon thermodynamic considerations. The Agrelot, et al. data show that almost 80 per cent of the total volume of air is bypassing, it is not directly participating in vaporization of the contaminants. Use of such a system for soils containing semi-volatile materials, such as jet fuel, diesel fuel, chlorinated phenols and biphenyls, polynuclear aromatics, and creosote with vapor pressures of one millimeter of mercury or less at room temperature will produce effluents containing only one to one hundred parts per million of contaminants. Treatment of the effluents containing such low concentrations of contaminants, including steps of extracting the low concentration contaminant vapors from the air and contaminant vapor mixture, is economically prohibitive. The quantity of air to be moved through the vacuum system to decontaminate a site also is very large, due to the large quantity of contaminant in a typical site and the low concentration of the contaminants in the effluent stream and bypassing. This makes such methods expensive for such applications.
U.S. Pat. No. 4,442,901 to Zison discloses an apparatus and method for recovering methane and other gases from a landfill by using shallow wells having a reduced pressure placed thereon. A gas barrier covers a portion of the site to prevent air from breaking through into the methane containing regions and induce flow of landfill gas into the collector from regions radially outward from the collector. The gas barrier may be a thin plastic sheet or a polymerized clay such as polymerized bentonite and may be coextensive with or extend radially outwardly beyond the collector.
U.S. Pat. No. 4,730,672 to Payne discloses a closed-loop system that treats contaminants by a combination of condensers, a carbon bed, and reinjection of the cleaned effluents back into the vadose zone under pressure. The method suffers from the same drawback as those discussed above because it produces dilute effluents and injects air under pressure into the vadose zone which may result in fugitive emissions.
Another major difficulty of some of the vacuum extraction systems of the foregoing systems, such as Zison, is that subsurface air flow patterns are inhibited or are subject to bypassing in the region of the collector. The bypassing subsurface air flow patterns have a quasi-cylindrical or spherical symmetry about vertical perforated collectors. Thus, at the more distant radial positions from the vertical collectors the air flow is low, whereas close to the perforated vertical collectors the air flow is large. This results in nonuniform decontamination, partly because air flow rate varies through the treatment region, but also because the absolute pressure varies greatly within the treatment region. Near the collector the pressure will be low enough to vaporize a wide spectrum of contaminants, whereas at the more distant points, the absolute pressure will be nearly atmospheric, resulting in incomplete decontamination at the volumes more distant from the collector.
Similarly to Visser et al., U.S. Pat. No. 4,957,393 to Buelt, et al. discloses a system that also is relatively inefficient. In one version Buelt, et al. require the air to be removed by vacuum at an opening at the bottom of each electrode. Such an arrangement causes air flow to bypass the main portion of the site being heated. Air flows directly from outside the processing area into the bottom parts of the electrodes which are located around the periphery of the area being processed. At the same time, the vapor pressures of the materials desired to be removed are increased to a point where they may escape into the atmosphere. In another version, Buelt, et al. suggest the use of a hood under a vacuum which is placed over the processing area. Again the system is such that air can bypass the contaminated region by flowing around the edges of the hood and not being drawn through the deposit being heated. In fact, the system proposed by Buelt, et al. does not rely on the use of an air sweep to dry out the deposit, but rather it depends on raising the temperature of the deposit to a point where the vapor pressures of the contaminants drive them out of the soil.
Buelt, et al. also heat the waste site to temperatures well above the boiling point of water, but less than the melting point of the soil constituents, for an extended period of time in order to volatilize contaminant material. Thus, Buelt, et al. rely upon heating the soil well above the boiling point of water to generate sufficient vapor pressure such that the contaminants are easily collected.
Such high temperatures have the advantage of being able to remove not only the semi-volatiles but also a substantial fraction of refractory compounds. However, the large amount of energy needed not only to boil the water off, but also to heat the deposit to a suitable temperature whereat the contaminants themselves are distilled, volatilized or pyrolyzed to generate sufficient pressure to cause their migration through the soil to the contaminant collection system is very expensive. The contaminants also may be forced from the contaminated region by steam drive. Steam distillation reduces the vapor pressure of the contaminant but at the expense of added equipment. However, such auxiliary procedures introduce further equipment complexity.
U.S. Pat. No. 4,973,811 to Bass discloses a decontamination system employing eddy current or induction heating of a contaminated site by an above ground RF transmission line 21 and connected electrodes 12 and 14 excited by a high RF current from a constant current RF source 20. A vapor barrier 24 confines the contaminant emissions from the site and is connected to ducts 22 to carry the contaminant vapor to a mobile treatment system 23. In order to prevent condensation of contaminant vapor above ground, sweep air is supplied over the site and a radiant surface 26 above the electrodes 12 and 14 may also be employed. When the site is dried the heating mode may be switched from induction heating to fringe field heating.
Bass requires a radio frequency generator for energization of the electrodes 12 and 14 in both the induction mode as water is being evaporated and the fringe field heating mode when the water has been driven off. Bass is effective only for treating relatively shallow contaminated regions due to the decrease in the eddy current density at deeper points of the site remote from the above electrodes 14 and 14. The Bass system also may release fugitive emissions from under the edges of the vapor barrier 24. Bass does not suggest the use of below ground vacuum or controlled air sweep to speed the vaporization of the contaminant.
U.S. Pat. No. 4,984,594 to Vinegar, et al. discloses an in situ method for removing contaminants from surface and near surface soil by imposing a vacuum on the soil and includes a surface heater energized from a source of low frequency electrical energy at a frequency of 60 Hz by means of a common bus line. A pumping manifold pipe is connected to a vacuum collection system 16 and is also coupled to a highly permeable mat 22 which serves as a conduit for flow beneath an impermeable sheet.
The Vinegar, et al. system suffers from the problem that vacuum extraction does not take place from deep in the earth, nor is there heating from in the earth. The system is only effective for removing materials from the very top of a contaminated soil surface.
SUMMARY OF THE INVENTION
According to the present invention, air flow through a site in the earth contaminated with a volatile or semi-volatile contaminant is controlled so as to reduce the costs of the air treatment system and to treat the contaminated site completely without areas of over or under treatment. Specifically, there is as uniform an air flow as possible. Such an air flow pattern differs from the type of fluid flow required for enhanced oil recovery wherein two different fluids, often of widely varying viscosity, mobility and relative immiscibility, occur in the deposit and the more mobile fluids, such as water, are used to push the less mobile oil into a production well.
The present invention overcomes the low vapor pressure limitation of prior art vacuum extraction methods by heating the soil of the treatment region in situ to an elevated temperature using conduction current or displacement current. Under these conditions, the system will not have to depend upon large quantities of air to effect vaporization of low vapor pressure substances. The amount of vacuum used in the practice of the present invention is relatively small and effective completion systems will overcome the second limitation of the uncontrolled air pathways that may bypass portions of the deposit. The third limitation is also overcome by heating since the increased vapor pressure causes the contaminant-to-air ratio to increase by an order of magnitude. Thus, the design of the completion system of the present invention for removal of contaminants minimizes air bypass, provides a high permeability path for collection of air containing the contaminants, and provides, insofar as possible a uniform air flow through the deposit by the use of extraction wells and tailored air infiltration regions.
The uniform flow of air may be realized in the practice of the present invention by the use of a horizontal drain positioned in or near the treatment region. Air at the surface of the earth is drawn vertically downward and flows more or less uniformly to the immediate vicinity of the drain from which a vacuum is drawn. In another embodiment of the present invention, uniform horizontal flow patterns of air are achieved by covering a portion of the surface of the earth with an impermeable sheet to limit the portions of the earth's surface through which air can flow. A plurality of effluent drain wells and a plurality of air injection wells arranged in a line drive of injection to produce a substantially uniform horizontal flow of air through the treatment region also may be employed.
The controlled flow referred to above is achieved by a structure that causes the air or gas entering the treatment region to enter all portions of the treatment region at substantially the same speed so that the entire treatment region will have contaminant extracted from its volume at substantially the same rate.
One apparatus which provides such controlled flow through the treatment region includes a plurality of vertical electrodes and a horizontal drain positioned beneath the vertical electrodes. The horizontal drain has a vacuum drawn on it by a vacuum pump or the like causing air to be drawn in through a ground surface, through the treatment region and into the drain. An impermeable sheet is placed immediately outside the periphery of the ground surface immediately above the treatment zone so that air only enters the ground from directly above the treatment region. As a result, the air flows at a uniform speed along substantially straight line paths through the treatment region until it reaches the immediate vicinity of the drain. The air flow through the treatment region is at a substantially uniform speed, with the exception of the area immediately surrounding the drain. This controlled flow of air tends to avoid fingering of the air stream that could cause portions of the treatment region to be left with contaminant therein when other portions have been decontaminated.
Another treatment apparatus comprises vertical air injection wells and vertical air-contaminant-water extraction wells positioned in alternating lines. The air injection wells and the extraction wells may also have immediately associated with them electrodes. The electrodes produce an electric field strength in the treatment region. The air from the air injection wells travels horizontally through the treatment region and is picked up by the extraction wells. The air injection wells are aligned as are the extraction wells. There are alternating rows of air injection wells and extraction wells so that the air flow is substantially coincident with the electric field and is also at a substantially constant velocity, with the exception of the regions immediately surrounding the electrodes. This is in order to provide uniform treatment and to prevent the regions immediately adjacent the electrodes from being dried out, which may disturb the conduction current pattern if conduction or ohmic heating is being used.
A still further apparatus providing controlled flow has vertical extraction wells wherein an impermeable layer closes off the upper surface of the treatment region to cause air drawn by the extraction wells to be pulled in through the sides, rather than the ground surface, of the treatment region. The air entering the sides of the treatment region enters all sides of the treatment region with substantially the same speed to provide a controlled flow path for uniform treatment and to avoid fingering which may leave untreated patches in the treatment region.
In the practice of the present invention where contaminants, such as mercury, which have a high boiling temperature are present, the contaminated site is heated to a temperature below the boiling point of the contaminant and yet above the boiling of water by the use of the radio frequency or dielectric heating by displacement current while being swept with a substantially uniform air sweep. The high boiling temperature contaminant is thereby carried to a collection region without the creation of new unwanted species of compounds by the excessively high temperatures which would be necessitated by the prior art systems. Moreover, the use of lower temperatures in combination with the substantially uniform air sweep reduces the energy required for the process, thereby decreasing costs.
The present invention is particularly directed to a method of and an apparatus for removing volatile and semi-volatile contaminants, such as gasoline and kerosene, from a contaminated site by the application of electromagnetic energy to elevate the temperature of the contaminated site sufficiently to increase the vapor pressure of all contaminants present within the heated contaminated earth while providing a controlled air flow through substantially all the earth. This avoids excessive removal of moisture near the electrodes when electrical conduction heating is employed. The contaminants are volatilized and transported to selected regions of the earth, where the effluents are collected and transported to an above ground system for their treatment and disposal. The method may be practiced by the emplacement in earth of a plurality of electrodes, oriented horizontally or vertically. Alternatively, in the case of dielectric heating above 100° C., some or all of the emplaced electrodes are used to create subatmospheric pressure within the contaminated earth, to cause controlled air flow through the earth, and to collect and transport the effluents from the earth to the treatment and disposal system.
In one embodiment of the invention, electromagnetic energy is applied to emplaced electrodes to heat the earth by conduction or ohmic heating. The earth can be heated to temperatures near the boiling point of water typically using commercial power frequencies of 50 or 60 Hz electric current. However, any frequency which is below 100 kHz and greater than 1 Hz and which is easily and economically generated is defined as a "power frequency" and can be used for conduction heating. The vapor pressure of many hydrocarbon contaminants, such as gasoline and jet fuel, is sufficiently high at temperatures near, but below 100° C. for their efficient removal with a controlled air flow through the earth. Certain hydrocarbon contaminants such as fuel oil, chlorinated phenols, and chlorinated biphenyls have vapor pressures on the order of one to ten millimeters of mercury at temperatures near 100° C. For such contaminants, it may be necessary to heat the earth using high frequency electromagnetic energy, such as 100 kHz to 100 MHz, to temperatures higher than 100° C. by displacement current or dielectric heating, in order to increase the vapor pressure of the contaminants to the order of ten to one hundred millimeters of mercury for their efficient collection with a controlled air flow.
The instant invention also may be practiced using a combination of low frequency and high frequency electromagnetic heating with the low frequency electromagnetic energy producing conduction current through the treatment region being used during the initial phase of heating to heat the earth to the boiling point of water and evaporate some of the water present therein, followed by high frequency electromagnetic energy producing displacement current through the treatment region to evaporate the remaining water and further heat the earth to temperatures above the boiling point of water.
Some of the electrodes emplaced in the earth can be used as extraction wells and others as air infiltration wells. For low frequency or conduction current heating, it is necessary to maintain the soil moist in the proximity of the electrodes in order to maintain an electrically conductive or low resistance path between the electrodes and the contaminated site. If some of the electrodes are used as air infiltration wells water or brine must be provided at the combination well and electrode locations because of the increase in resistance caused by enhanced evaporation and drying due to the low pressure and high current in the immediate vicinity of the combination well-electrodes. Hence, for the low frequency or conduction current embodiments of the invention, it is preferred that extraction and infiltration wells be separate from electrodes and separate flow paths be established for air and electromagnetic energy if water injection is not provided.
In the practice of the present invention extraction wells are emplaced in the contaminated earth either vertically or horizontally. A vacuum is drawn through the extraction wells creating a subatmospheric pressure zone in the below-ground collection region of the site, resulting in a pressure gradient from the earth's surface to the collection region. The location and design of the air infiltration wells or regions results in a controlled flow of air at a substantially uniform speed through substantially all of the contaminated site. The contaminants are volatilized under the combined actions of the subatmospheric pressure and flowing air, transported from the contaminated zone to the collection region, and then through the extraction wells to the effluent treatment and disposal system, rather than escaping through the upper portion of the site into the atmosphere.
Because the electrodes extend below the surface of the site and contact the earth, whether they are oriented horizontally or vertically, they provide a spatially quasi-uniform, electrical current conduction heating region extending deep into the earth to heat the earth uniformly so that the entire contaminated volume is treated.
In addition, in the practice of the instant invention, a vapor barrier may be placed over substantial portions of the site to control the flow of air throughout the deposit. This causes air to interact completely with the soil via long flow paths and controls fugitive emissions. The vapor barrier also causes air to be drawn in from the sides or top of the site, providing a controlled path air sweep through the site to remove contaminants without having flow rates, in the case of conduction heating, at the electrode surfaces which might dry the earth in proximity with the electrodes and interrupt the electrical conduction heating. Because of the increased temperature, the relative concentration of the contaminant vapor due to increased vapor pressure in the contaminant-air mixture is high, allowing a substantial position of the contaminant to be removed by condensation of the contaminant-air mixture followed by final clean-up of the contaminant-air mixture by carbon adsorption beds and the like of the effluent treatment and disposal system located above the site and coupled to a vacuum pump. Water vapor present in the effluent stream is condensed simultaneously with the contaminant, and the mixed condensed phase is further separated to separate water and contaminant. The high contaminant vapor concentration results from the air only mixed with the contaminant vapor being drawn through the sides of the site by the vacuum, and not from directly above the surface of the site.
In the preceding description of the instant invention, controlled flow of air through the contaminated earth is described. Even though use of atmospheric air is the preferred method, in certain instances it may be more advantageous to introduce heated air or another fluid into the contaminated site. For instance, air may be preheated to approximately the same temperature as the contaminated earth or to a somewhat higher temperature to compensate for heat loss from the heated earth to the surroundings and to eliminate the need for continuous or intermittent deposition of electromagnetic energy to supply the heat required to increase the temperature of the flowing air from ambient atmospheric temperature to the ambient temperature of the contaminated earth. This is achieved by introducing preheated air into air infiltration wells. Air can be preheated by a number of means including CALROD electric resistance heaters, and gas and oil burners, and can be supplied to the air infiltration wells by insulated pipes or ducts. The pressure gradients generated within the contaminated site cause the flow of the heated air through the infiltration wells. Steam or hot water vapor is more effective than air in desorption of certain contaminants, such as polar compounds and polynuclear aromatics, from earth, in particular when clay is present in contaminated earth, due to the enhanced wetting of minerals by steam relative to air. Nitrogen and steam may be preferred over air in certain instances if the contaminated earth contains a large concentration of chlorinated phenols and biphenyls, and the earth is heated to temperatures higher than about 200° C. This prevents the oxidative formation of toxic compounds.
Certain inorganic contaminants having relatively high vapor pressures also can be removed using the instant invention. For example, certain inorganic compounds of antimony, arsenic, beryllium, bismuth, cesium, mercury, sulfur and zinc have vapor pressures in excess ten millimeters of mercury in the temperature range of 150° C. to 500° C., and can be removed from earth using the instant invention.
It is a principal aspect of the present invention to provide a method of and an apparatus for removal of volatile heavy fraction contaminants from a contaminated site.
It is another aspect of the instant invention to provide a method of and an apparatus for in situ decontamination of a site by a combination of heating and pressure reduction in a nether portion of the site.
It is an aspect of this invention to provide a controlled air flow pathway for air so as to process completely a portion of a contaminated deposit.
It is an aspect of this invention to further provide a controlled air flow pathway so as to avoid excessively depleting the moisture near electrodes where conduction heating is employed.
Further, it is an aspect to suppress fugitive emissions by proper control of the air flow pathway.
It is another aspect to recover both volatiles and semi-volatiles with simple, low cost apparatus that avoids the need to develop high deposit temperatures much in excess of 150° C.
It is another aspect of this invention to recover inorganic material that has a vapor pressure in excess of ten millimeters of mercury in the temperature range of 150° C. to 500° C.
It is a further aspect of the present invention to provide a method of and an apparatus for in situ decontamination of a site contaminated with a heavy volatile material by electrically heating water within the site so that when the pressure at the site is reduced in a subsurface collection region the heavy volatile material may be easily recovered.
It is a still further aspect of the present invention to provide a method of and an apparatus for in situ decontamination providing a contaminant rich contaminant-air stream for ready recovery of the contaminants by adsorption and the like.
Other aspects of the present invention will be apparent to one of ordinary skill in the art from the specification and claims in light of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a prior art decontamination system;
FIG. 2 is a sectional view of the prior art decontamination system shown in FIG. 1 and taken generally along line 2--2 of FIG. 1;
FIG. 3 is a sectional view of the prior art decontamination system shown in FIGS. 1 and 2 in operation in a contaminated site with air flow paths and isobars shown thereon;
FIG. 4 is a sectional view of a first decontamination system embodying the present invention and having an extraction well which is open only at the bottom of the well;
FIG. 5 is a sectional view of a second controlled flow vertical perforated vacuum extraction well embodying the present invention and placed in a contaminated site and drawing air therethrough to remove volatile contaminants from the site;
FIG. 6 is a top elevational view of a third decontamination system embodying the present invention and having multiple horizontal drains;
FIG. 7 is a sectional side view of the third decontamination system shown in FIG. 6;
FIG. 8 is a sectional view of the third decontamination system shown in FIGS. 6 and 7 taken substantially along line 8--8 of FIG. 7;
FIG. 9 is a sectional view of a fourth decontamination system embodying the present invention;
FIG. 10 is a sectional view of the fourth decontamination system shown in FIG. 9 and taken generally along line 10--10 of FIG. 9;
FIG. 11 is a detailed sectional view of an electrode of a fifth decontamination system embodying the present invention showing details thereof;
FIG. 12 is a perspective view, partially in section, of a sixth decontamination system embodying the present invention having vertical electrodes and a horizontal drain;
FIG. 13 is a sectional view of a a tenth decontamination system embodying the present invention and having a vertical extraction well and horizontal electrodes;
FIG. 14 is a sectional view of a ninth decontamination system embodying the present invention and having a vertical extraction well and a plurality of vertical electrodes;
FIG. 15 is a sectional view of a portion of the eighth decontamination system embodying the present invention and having a vacuum extraction well extending through a gas impermeable barrier resting upon the ground above the contaminated region;
FIG. 16 is a perspective view of a portion of a seventh decontamination system embodying the present invention, including a vacuum extraction system having a plurality of vertical wells and an electrical heating system having a plurality of vertical electrodes for providing electric current to a contaminated region of the earth;
FIG. 17 is a sectional schematic view of an eleventh decontamination system embodying the present invention, similar to that shown in FIGS. 9 and 10, including a pair of horizontal electrodes and a horizontal extraction well;
FIG. 18 is an elevational view of an eighth decontamination system, embodying the present invention having a plurality of vertical extraction wells and vertical electrodes positioned in a contaminated region of the earth;
FIG. 19 is a sectional view of the eighth decontamination system shown in FIG. 18 and taken generally along line 19--19 thereof;
FIG. 20 is a sectional view of the eighth decontamination system shown in FIG. 18 and taken generally along line 20--20 thereof;
FIG. 21 is a sectional schematic view of a twelfth decontamination system embodying the present invention having vertical electrodes and a horizontal extraction well; and
FIG. 22 is a block diagram of an effluent disposal and treatment system of the aforementioned decontamination systems connectable to a vacuum pump to receive and treat an effluent stream comprising air, water vapor and contaminant liquid and vapor drawn from the contaminated region.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and especially to FIGS. 1 through 3, the prior art system of Visser, et al. is shown therein. The Visser, et al. system, which is generally identified by numeral 10 is used for extracting a contaminant from earth 12 at a treatment region 14 which is a portion of the vadose or above ground water zone of the earth which may be contaminated with a volatile contaminant such as carbon tetrachloride and the like. A well 16 is formed therein having a perforated vapor collection tube 18 in place therein. A permeable substance 20 is positioned in the well 16 surrounding a lower portion of the collection tube 18. An impermeable material 22 seals the upper portion of the well 16 in order to reduce fingering. The collection tube 18 has connected to it a vacuum pump 24 for drawing a vacuum through the collection site and a collection and disposal system 26 for further processing of an air-contaminant vapor stream drawn from the ground 12. A slightly different embodiment of the prior art system is shown in FIG. 3 wherein details of the impermeable material 22 and permeable material 20 are not included in the figure. The collection tube 18 having the plurality of collection apertures 19 is shown therein and in addition, a plurality of isobars are shown in dotted form with an isobar 30 representing the 1.5 inches of mercury line and isobar 32 representing the 2 inches of mercury line and isobar 34 delineating the 5 inches of mercury line and an isobar 36 delineating the 10 inches of mercury line. The various pressures may be measured by a plurality of measuring wells 40, 42 and 44, each having vacuum measuring devices 46 positioned at various points therein. It may be appreciated that due to the relatively small pressure differential, except along isobar 36 for 10 inches of mercury, appreciable vaporization of the contaminant in the ground will not take place due to reduction in the ambient pressure by the vacuum system. Thus, the vacuum system must rely primarily for removal of air flowing along air flow paths 50, primarily coming in from the surface of the site.
A first embodiment of a portion of the present invention is shown in FIG. 4 wherein a vacuum extraction system 100, which provides controlled air flow paths, is shown. The vacuum extraction system 100 is positioned in the earth 102 and more particularly in a treatment region 104 of the earth which has soil contaminated with a volatile or semi-volatile contaminant. A well 106 is formed in the earth and a collection tube 108 is then placed in the well 106. The collection tube 108 is cylindrical and has a collection opening 110 at a bottom thereof. An impermeable packing material 112 surrounds the collection tube 108 and an impermeable membrane 114 extends approximately twice the width of the treatment region 104 so that the air flow 115 through the treatment region 104 caused by a vacuum pump 116 connected to the collection pipe 108 is substantially uniform over a major portion of the volume being treated. The air speed is roughly constant through the outer portions of the treatment region 104, with the exception of the portion of the treatment region 104 immediately adjacent the collection opening 110, the vacuum pump 116 is connected to the collection and disposal system 26 for removing contaminant vapor from the effluent stream comprising air, contaminant vapor and water from the treatment region 104. The controlled air flow avoids fingering and prevents pockets of untreated zones remaining in the treatment region 104.
A second embodiment of the vacuum extraction portion of the instant invention is shown in FIG. 5 and includes a vacuum extraction system 200 comprising means for generating a controlled air flow through a treatment region. The vacuum extraction system 200 is placed partially in the ground 202 and more specifically in a vadose zone 203 thereof. For removal of a contaminant from a treatment region 204, the contaminant may be carbon tetrachloride, gasoline, jet fuel, kerosene, or the like. An extraction well 206 has an extraction tube 208 having a plurality of collection openings 210 formed therein positioned in a permeable material 212 such as sand. A membrane 214 abuts against the collection tube 210 of the well 206 and extends approximately twice the width of the treatment region 204 to cause air to flow via the controlled flow paths 216 at substantially constant velocity throughout a major portion of the the treatment region except in the immediate vicinity of the perforations 210 so that the entire treatment region is treated. A take-off tube 218 is connected to the tube 208. A vacuum pump 220 draws contaminant vapor, air and water vapor from the take-off tube 218 and by reducing the pressure in the well 206 causes the air to flow in through the ground surface 202a along the controlled flow substantially constant speed paths 216. The resulting effluent mixture is fed to the collection and disposal system 26.
A third embodiment of a controlled air flow system for performing vacuum extraction via controlled air flow is shown in FIGS. 6, 7 and 8. The system is generally identified by reference numeral 300 and has portions positioned in the ground 302, in particular, in a vadose zone 303 of the ground 302. A treatment region 304 in the ground 303 has a contaminant therein which is volatile or semi-volatile. A plurality of horizontal drain tubes 306, 308, 310 and 312 is positioned in the ground. The drain tubes are perforated and are connected to a manifold 314 connected to a vacuum pump 316 which draws a vacuum on the tubes 306, 308, 310 and 312. An effluent stream from the vacuum pump 316 is delivered to the collection and disposal system 26. It may be appreciated that when the vacuum is drawn, air flows in through the ground surface 302a along substantially vertically oriented paths 322. The air flow is at substantially a uniform speed through substantially the entire treatment region 304 with the exception of the portions of the treatment region 304 immediately adjacent the horizontal drain tubes 306, 308, 310 and 312. Thus, a controlled air flow is achieved which allows rapid and thorough treatment of the entire treatment region 304 without fingering which could leave volatile contaminants behind. It may be appreciated that because the drain tubes are positioned beneath the treatment region although the air flow curves in toward the drain pipes 306, 308, 310 and 312, nevertheless the air flows at substantially uniform speed through the treatment region 304.
A fourth embodiment of the present invention comprises the decontamination system 400 shown in FIGS. 9 and 10 and has portions in place in the earth 402 under its surface 402a and positioned in a vadose zone 403. A means for drawing a subatmospheric pressure in a nether collection region comprises a drain well 406 having a slanting tube 408 connected in communication with a perforated tube 410 which is positioned between the treatment region 404. The slanting tube 408 is connected to a vacuum pump 414. A packing material or well completion material 412 surrounds the slanting tube 408 to prevent bypassing of air along the slant line so that controlled air flow may take place when the vacuum is drawn by the pump 414. Effluent stream from the pump 414 is delivered to the collection and disposal system 26 connected thereto. An electrical heating means includes a power source 418, which in this embodiment may either be a source of 50 or 60 Hz electrical energy for conduction heating or a source of radio-frequency energy having a frequency between 6 and 13 megahertz for displacement current heating. The power source 418 is connected to an array of vertically positioned electrodes 420 having their major portions buried in the treatment region 404. A packing material 422 surrounds the electrodes and may comprise a mixture of brine and sand for good electrical conduction if the power source 418 is operating at 50 or 60 Hz. In operation, the power source 418 causes either a conduction or displacement current to flow between the two rows of electrodes thereby heating the soil in between while the vacuum is drawn. The vacuum causes air to flow along flow lines 424 through the ground surface 402 through the treatment region 404 and into the horizontal drain 410. The air flows at a substantially constant speed so that all portions of the treatment region 404 are being treated by the air flow and no portions will have contaminant remaining after treatment is completed. Since the system 400 uses electrical heating in combination with the controlled air flow vacuum extraction, semi-volatile materials such as jet fuel and the like may be easily removed.
A fifth embodiment of the present invention is shown in FIG. 11 and includes vacuum extraction means as well as electrical heating means. The vacuum extraction means of the system 500, which extends into the ground 502 through a ground surface 502a thereof, in contact with a treatment region 504, which is contaminated, includes a vacuum extraction well 506. The vacuum extraction well 506 has a central well metal member 510 having spaced pluralities of apertures 512 formed therein for receiving contaminant vapor. A vacuum line 514 is connected to the tube 510 and to a vacuum pump 516 which feeds effluent from the treatment region 504 to the collection and disposal system 26 connected to it. The electrical heating means includes a power source 520 which may either be a conduction current source or a displacement current radio-frequency source feeding electric power through a line 522 to the metal tube 510. The metal tube 510 includes a plurality of integrally formed circumferential air-impermeable annular rings 522 that contact the treatment zone 504 in good low resistance electrical contact. The air impermeability assures that air flow wil not deplete the moisture needed for ohmic contact with the deposit during conduction heating. This is to transfer electrical energy from the rings 522 to the treatment region 504 in order to heat the treatment region 504 either with displacement current or conduction current. The heating releases volatile and semi-volatile contaminants such as jet fuel from the treatment region 504. At the same time the vacuum system, including the vacuum pump 516, draws air, water, vapor and contaminated vapor through the extraction well 506 causing air to flow through the sides of the treatment region 504 because an impermeable membrane 526 is positioned above the treatment region extending past its boundaries. The air flow is best indicated by the flow lines 528.
As may best be seen in FIG. 12 a sixth embodiment of the inventive decontamination system 600, is emplaced in the earth 602 with portions extending through a ground surface 602a. A treatment region 604 in the earth 602 is contaminated with a volatile or a semi-volatile organic contaminant such as kerosine, jet fuel, gasoline or the like. A first impermeable sheet 606 is positioned outside the treatment area, a second impermeable sheet 608 is positioned opposite the sheet 606 past the other side of the treatment area 604. A horizontal drain 610 is positioned beneath the treatment area and includes a plurality of vacuum extraction apertures 612. The horizontal drain 610 is connected to a vacuum pump which is in turn connected to the collection system 26 for extraction of effluent vapors. A first electrode assembly 612 has a portion positioned in the ground as does a second electrode assembly 614. A power source 616, which produces low frequency electrical energy typically having commercial frequencies of 50 or 60 Hz, energizes a horizontal tube 618 of electrode assembly 613 and a horizontal tube 620 of electrode assembly 614. The frequency range is not limited to commercial frequencies of 50 or 60 Hz but could be in any of the so-called power frequencies which can range from 1 Hz to 100 kHz. A vertical perforated tube 622 is connected to horizontal tube 618, a vertical perforated tube 624 is connected to horizontal tube 614. The perforated tubes are positioned respectively in well bores 626 and 628 and have a conductive material such as sand mixed with brine 630 positioned about them to place them in good electrical conduction with the ground 602 and the treatment region 604. Water or brine may be fed from an outside source through the tube 618 into the vertical tube 622 and likewise through the tube 620 into the vertical tube 624, a water exits the perforations in the vertical tubes 622, 624 to soak the sand 630 to ensure that it remains conductive even while electrical heating is occurring due to the conduction current flowing from the power source 616. In addition, the outer boundary impermeable sheath 606 and 608 block air flow from the sides causing all air flow through the treatment region to come straight through from the top at a substantially constant speed so that there is a substantially constant removal of contaminated vapor from the treatment region 604.
A seventh embodiment of the present invention is shown in a decontamination system 700 shown in FIG. 16. The decontamination system 700 includes three rows of vertical electrodes, respectively numbered 702, 704 and 706, which are positioned partially in ground 708 extending through a ground surface 708a. The rows of electrodes 702 and 706, as well as 704, are connected to a conduction current power source 710 which feeds power through a plurality of cables 712 to the rows of electrodes. Rows 702 and 706 comprise extraction well electrodes and are coupled via a vacuum line 714 to a vacuum pump 716 which is connected to the treatment system 26. All three rows of electrodes may be provided with brine or water in order to maintain the conductivity of the electrodes within the ground. The electrode row 704 is connected via a pipe 720 to a water tank 724. An air intake treatment tank 722 is used to remove dust particles which could clog the flow paths to provide a fugitive emission seal in the event of a shut down and to preheat the intake air if needed. A water tank 726 is connected via a line 728 to the pipe 714 to supply water to the electrodes of rows 702 and 706 to maintain conductivity.
As may best be seen in FIGS. 18, 19 and 20, an eighth decontamination system, generally identified by 800 and embodying the present invention, includes five rows of vertical electrodes positioned in ground 802. Three rows of vacuum extraction electrodes 804, 806 and 810 have interspersed in between them, air injection electrodes rows 812 and 814. A power source 816 has one of its sides connected to the air injection electrodes 812 and 814, the other side connected to the vacuum extraction electrode rows 804, 806 and 810 to provide an electric field which is substantially uniform throughout a treatment region 820. The electrode row 804 includes a header 830, the electrode row 806 includes a header 832, a header 834 is connected to the row 810, a header 836 is connected to the row 812, a header 838 is connected to the row 814. It is actually the headers which are connected to the power source 816. Headers 836 and 838 receive air which flows into the intake wells. The headers 830, 832 and 834 are connected to a vacuum manifold 840 which is connected to a vacuum pump 842, feeding effluent to the collection and disposal system 26. When the power source 816 energizes the electrodes with electrical energy at conduction current frequencies at 45 Hz to 60 Hz, a substantially uniform conductive current is established through the treatment region 820 to uniformly heat it. Likewise, the air flow is substantially uniform throughout the treatment region 820 and comprises a controlled flow having a substantially constant speed except in the immediate neighborhood of the air injection wells and extraction wells. This allows complete recovery of volatile and semi-volatile contaminants from the treatment region 820. Further, the air flow is well controlled by the use of the impermeable sheet 850, positioned over the entire treatment region 820 so that flow into the treatment region is restricted to the controlled flow through the air injection electrodes and the flow out of the treatment region is controlled solely by the extraction wells.
Further detail of one of the air injection wells is shown in FIG. 15 which shows the air injection well 814 with the impermeable sheet 850 positioned about portions of it, the impermeable sheet is cut-off and does not extend all the way across the picture. The well 814 includes a perforated tube 860 having a plurality of perforations 862 formed therein to release air into the treatment region 820. A loose, highly permeable packing material, such as loose sand 864 is packed around the tube 860 to allow the air to flow through easily.
Referring now to FIG. 14, a ninth decontamination system 910 embodying the present invention is shown therein for removing contaminants from a site 912 in the earth. The system 910 includes electric heating means 914 for electrically heating the site and a vacuum pump 916 for applying subsurface subatmospheric pressure to a zone 918 in a nether region of the site 912. The system 910 includes the collection and disposal system 26 for collecting contaminant vapor from an effluent stream received from the nether zone 918 and is connected to the pump 916. An impermeable sheet 922 for controlling the flow of air covers the site 912.
The heater for electrically heating 914 includes an alternating current generator 924 which produces electrical energyat a power-frequency of 50 or 60 Hz. The alternating current generator 924 feeds alternating current over lines 926 and 928 to a plurality of electrodes 932, 934, 936, which are partially buried in the site 912. The plurality of electrodes includes a first outside electrode 932, a second outside electrode 934 and a middle electrode 936. The outside electrodes 932 and 934 are held at ground potential while the middle electrode 936 is excited. It may be appreciated that the electrode 932 has a buried portion 940 and an above-ground portion 942, the electrode 934 has a buried portion 944 and an above-ground portion 946, and the electrode 936 has a buried portion 948 and an above-ground portion 950. The site 912 includes a site or ground surface 952, which is immediately above a vadose zone 954. Included within the vadose zone 954 is a contaminated region 956 in which the electrode 936 is partially buried. The electrodes 932 and 934 straddle the contaminated region 956 and are positioned slightly outside it. It may also be appreciated that the nether region 918 is immediately beneath the contaminated region 956.
The vacuum pump 916 is connected to a descending vacuum line 960, partially buried in the site 912. The descending line 960 having a plurality of apertures 962. When energized, the vacuum pump 916 reduces the pressure in the nether region 918 to a subatmospheric pressure, causing air to be drawn in from the ground 952 around the site 912. At the same time, electrical energy is supplied by the generator 924 to the plurality of electrodes 932, 934, 936, heating the contaminated region 956, which may contain light or heavy hydrocarbons such as kerosene therein. Due to the heating of the region 956, the contaminants are partially vaporized and are carried by an air stream 970 into the collection openings 962. In order to assure a complete air sweep through the contaminated region 956 without fingering or channelling, the impermeable sheet 922, such as a plastic sheet, is provided. The sheet 922 extends laterally for a distance twice the maximum depth of the contaminated region 956 to allow adequate controlled air flow through the region 956 in order to trap and entrain the vapor therein. The sheet 922 also prevents evaporation of water on the electrodes to prevent loss of conduction. The collected mixture of air, water vapor, and contaminant vapor is fed to the collection and disposal system 26.
The collection and disposal system 26 is shown in FIG. 22 and is of conventional design. A gas-liquid separator 976 is connected to the line 974 and receives the fluid stream therefrom. Separated liquids are fed via a line 978 to a liquid-liquid separator 980. Separated gases are fed via a line 982 to a condenser-cooler 984 where heat is removed from the fluid stream, allowing some of the vapors to condense. The cooled vapors are output, along with the liquid, via a line 986 to a gas-liquid separator 988. In order to ensure adequate cooling, a cooling loop 990 is provided having a cooling tower 992 connected to an input line 994 from the condenser-cooler 984. The cooling tower transfers heat from a water stream to the atmosphere, and cooled water is fed from the cooling tower through a line 996 to a pump 998 and thence through a line 1000 to the condenser-cooler 984.
The gas-liquid separator 988 has an output gas line 1002 and a liquid line 1004 connected thereto. The gas line communicates with a fan 1006, the output of which is connected to a demister 1008. The line 1004 supplies liquid to the liquid-liquid separator 980 as does an output line 1010 from the demister 1008. Gases from the demister 1008 are fed via a line 1012 to a catalytic incinerator 1014 used for non-chlorinated contaminant. When chlorinated contaminant is to be treated a chiller and associated carbon bed adsorber are substituted for the catalytic incinerator 1014. The liquid-liquid separator 980 has an output light organic phase line 1016, an output heavy organic phase line 1018, and an output water line 1020 connected thereto. A light organic phase pump 1022 feeds the light organic phase material from the line 1016 through a light organic phase line 1024 to the incinerator 1014, delivering waste light organic compounds, such as hexane and heptane, to the incinerator 1014. A heavy organic phase pump 1026 feeds material from the line 1018 through a heavy organic phase line 1028 to the incinerator 1014 for feeding heavier organic compounds such as kerosene recovered from the site contaminated region to the incinerator 1014 where they are oxidized. Water from the contaminated region is fed by a line 1020 to a pump 1030 which delivers the water to a pH adjuster 1032 for neutralizing any acidity in the water. The water is then filtered by a pressure filter 1034 connected to a line 1036 between the pH adjustor 1032 and the pressure filter 1034. An output line 1038 from the pressure filter 1034 supplies pH 7.0 filtered water to a carbon bed absorber 1040 which removes any remaining contaminants filtered water to generate a treated water stream in an output line 1042 for use in other portions of the equipment.
Referring now to FIG. 13, a tenth embodiment of the aforementioned invention is shown therein including an apparatus 1100 for removing volatile contaminants. The apparatus 1100 is positioned at a site 1102, having a surface 1104, and a contaminated region 1108. There is a nether region 1110 of the contaminated region 208. The contaminated region 1108 contains volatile hydrocarbon contaminants, such as kerosene, which must be removed. The collection and disposal system 26 includes a heating system 1114 for electrically heating the site and a vacuum pump 1116 for creating a subatmospheric pressure zone in the nether region 1110. The collection and disposal system 26 is connected to the pump 1116. There also is a sheet 1102 for controlling the flow of air through the site 1102 in order to reduce changes in the electrical properties of the site 1102 due to evaporation of water therefrom.
The electrical heating system 1114 includes a power source 1124 of 50 or 60 Hz electrical energy connected to lines 1126 and 1128. The line 1128 is connected to a pair of horizontal electrodes 1132 and 1134. A horizontal electrode 1136, positioned between electrodes 1132 and 1134, is connected to the line 1126. It may be appreciated that the electrodes define an electrical heating region of size substantially the same as or greater than that of the treatment region 1108.
The pump 1116 is connected to a vertical vacuum extraction line 1140 having a plurality of holes 1142 formed therein in the nether region 1110. Vacuum pump 216 feeds a contaminant line connected to the collection and disposal system 26. Electrical energy from the alternating current source 1124 causes electrical conduction current to flow through the contaminated region 1108 resulting in the region's being heated, thereby increasing the vapor pressures of contaminants therein. Simultaneously, air is swept through the contaminated region 1108 from the surface 1104 but not through portions of the surface 1104 lying underneath the sheet 1122. The air follows a flow path 1150, which causes it to stream through the contaminated region 1108, picking up contaminant vapors therein and carrying them with the air into the collection line 1140 where they are pumped out by the vacuum pump 1116 and delivered to the collection and disposal system 26. The region of greatest pressure differential for the air flow, it may be appreciated, is spaced from the greater part of the horizontal electrodes 1132, 1134, 1136 so that substantial evaporation of water in the region of the horizontal electrodes does not take place, as it would interrupt flow of the conduction current and heating of the contaminated region 1108. It may also be appreciated that only a current sufficient to heat the contaminated region 1108 to a temperature below the boiling point of water is provided in order to ensure that the vapor generated by the heating is vented solely through the line 1140 for later collection and disposal as set forth above.
In an eleventh embodiment, as may best be seen in FIG. 17, an apparatus 1200 for decontaminating a site 1202 is provided. The site 1202 includes a site surface 1204 and a contaminated region 1206 having a nether region 1208. The site 1202 is a portion of earth which has been contaminated with kerosene or the like, which may have been caused by leaks or spills. There also is provided a heating system 1214 for electrically heating the contaminated region 1206 and a vacuum pump 1216 for reducing to subatmospheric the pressure the nether region 1208. The system 26 for collecting the contaminant vapor is connected to the pump 1216.
The electrical heating system 1214 includes a source of electrical energy 1224, which generates 50 or 60 Hz alternating current supplied to lines 1226 and 1228, electrically connected to a first horizontal electrode 1232, a second vertical electrode 1234. A horizontal collection pipe 1250, having a plurality of holes 1252, extends beneath the treatment region 1208. The collection pipe 1250 is connected to the vacuum pump 1216 to deliver effluent contaminant, water vapor, and air to the collection and disposal system 26 provides constant speed controlled air flow along lines 1256 as set forth above.
As shown in FIG. 21, a site 1300 in the earth having a ground or earth surface 1302 has a contaminated region 1304, a surface 1305, and a nether collection region 1306. A twelfth system 1312 for decontaminating the site 1300 includes an electrical heating system 1314 for electrically heating the site and a vacuum pump 1316 for reducing the pressure of the nether region 1306 to a subatmospheric pressure level. The collection and disposal system 26 receives the output of the pump 1316. A pair of impermeable sheets 13 and 1323 extends outside the contaminated region 1304.
The electrical heating system 1314 includes a source 1324 of 50 or 60 Hz electrical energy supplied to a pair of lines 1326 and 1328. A plurality of vertical electrodes 1332, 1334, 1336 are connected to the lines 1326 and 1328 to receive electrical energy in the form of electric current therefrom. The line 1326 is connected to the center electrode 1332, and the line 1328 is connected to the outside electrodes 1334 and 1336. Electrodes 1334 and 1332 extend outside and adjacent to the contaminated region 1304 to define a conductive field region therein.
The vacuum pump 1316 is connected by a downwardly extending vacuum line 1342 positioned in impermeable material 1343 to an elbow 1344 in turn connected to a horizontal line 1346, having a plurality of openings 1348 formed therein, positioned permeable material 1349 in communication with a sump 1350 having a liquid pump 1352 and a pump drive 1354 with a liquid removing lines 1356 in the nether region 1306 of the site 1302, immediately below the contaminated region 1304. In operation, electrical energy generated by the generator 1324 causes conduction current to flow between the electrode 1332 and the electrodes 1334 and 1336, causing the contaminated region 1304 to be heated, increasing the vapor pressure of contaminants therein, and at least partially converting the contaminants to vapors. Simultaneously, the vacuum pump 1316 is energized, reducing the pressure in the nether region 1306, causing air to be drawn in from the surface 1302 in a controlled constant speed flow 1360, except where bounded by the impermeable sheets 1322. The air sweeps through the contaminated region 1304 and into the collection holes 1348 whence it is drawn up the pipe 1346 through the elbow 1344 and the pipe 1342 by the vacuum pump 1316 and delivers the effluent mixture of air, contaminant vapor and water vapor to the collection and disposal system 26. It may be appreciated that the controlled flow does not concentrate the air flow immediately adjacent the electrodes 1330, thereby helping to limit the evaporation of water around the electrodes and consequent reduction in conduction therefrom.
It may be appreciated that the present system provides an economical method for removing heavy fraction contaminants from a contaminated site. The system uses a combination of electrical heating and pressure reduction combined with substantially uniform speed controlled air flow to effect the removal. The air flow is controlled so that relatively limited portions of the water at the site are evaporated to prevent loss of electrical conduction at the site. Thus, relatively inexpensive electrical generators producing electrical current having a frequency of 50 Hz or 60 Hz may be used rather than more expensive radio frequency generators used for dielectric heating. The electrical heating increases the vapor pressures of the heavy fraction contaminants, more easily vaporizing them. The vaporization is assisted by the vaporization of a portion of the water in the site because the heated water vapor helps to strip the contaminants from the earth. The freed contaminant vapor is then carried by the air stream into the collection region where it is drawn off through the vacuum line and subsequently disposed of.
While there have been illustrated and described particular embodiments of the present invention, it will be appreciated that numerous changes and modifications will occur to those skilled in the art which fall within the true spirit and scope of the present invention. | A method for removing a contaminant from a treatment region of a contaminated region of a site in the earth having water therein and being contaminated with the contaminant includes heating the earth by establishing an electric field through the treatment region. The electric field gives rise to an electric conduction or displacement current through the treatment region. The electric current electrically heats at least a portion of the treatment region to a temperature below the boiling point of water to evaporate the water. A vacuum is drawn in a nether region of the site to collect water vapor evolved from the water and contaminant vapor evolved from the contaminant by movement of air from the surface of the earth, while the water vapor strips the contaminant from the earth. The contaminant vapor is disposed of in an innocuous manner. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to optical sampling of tissue in vivo. More particularly, the invention relates to a fiber optic probe placement guide and optical coupler for repeatably sampling a tissue measurement site in vivo.
2. Description of the Prior Art
Noninvasive prediction of blood analytes, such as blood glucose concentration, may employ NIR spectroscopic methods. A commonly assigned application, S. Malin and T. Ruchti, An Intelligent System For Noninvasive Blood Analyte Prediction, U.S. patent application Ser. No. 09/359,191; Jul. 22, 1999 describes a system for noninvasively predicting blood glucose concentrations in vivo, using NIR spectral analysis. Such NIR spectroscopy-based methods utilize calibrations that are developed using repeated in vivo optical samples of the same tissue volume. These successive measurements must yield a substantially repeatable spectrum in order to produce a usable calibration. The heterogeneous and dynamic nature of living human skin leads to sampling uncertainty in the in vivo measurement. Sampling differences can arise due to variable chemical composition and light scattering properties in tissue. As an example: because glucose is not uniformly distributed in tissue, a variation in the volume of tissue sampled is likely to lead to a variation in the strength of the glucose signal, even though glucose concentration in the tissue or blood remains constant. Variation in the placement and replacement of the fiber optic probe used for optical sampling at the measuring surface can lead to sampling in errors in two separate ways: variations in location of the probe can cause a different tissue volume to be sampled; varying the amount of pressure applied to the probe can alter the amount of tissue displaced, causing a larger or smaller tissue volume to be sampled. A change in optical sampling may lead to a variation in the spectral signal for a target analyte even though the concentration of the analyte in the blood or tissue remains unchanged. Furthermore, air gaps between the surface of the fiber optic probe and the surface of the tissue being sampled are another source of sampling error.
Various systems for guiding and coupling fiber optic probes are known. For example, M. Rondeau, High Precision Fiberoptic Alignment Spring Receptacle and Fiberoptic Probe, U.S. Pat. No. 5,548,674; Aug. 20, 1996 and R. Rickenbach and R. Boyer, Fiber Optic Probe, U.S. Pat. No. 5,661,843; Aug. 26, 1997 both disclose fiber optic probe guides utilizing ferrules through which a fiber optic cable or thread is longitudinally threaded. Both devices are connectors that couple fiber optic cables or threads to receptacles in various forms of medical equipment, or to other fiber optic cables. Neither device provides a means for repeatably coupling a fiber optic probe to a tissue measurement site.
T. Kordis, J. Jackson, and J. Lasersohn, Systems Using Guide Sheaths for Introducing, Deploying and Stabilizing Cardiac Mapping and Ablation Probes, U.S. Pat. No. 5,636,634; Jun. 10, 1997 describe a system that employs catheters and guide sheaths to guide cardiac mapping and ablation probes into the chambers of the heart during surgery or diagnostic procedures. The Kordis teachings are directed to surgical methods for the heart, and have nothing to do with optical sampling of tissue in vivo. Furthermore, the apparatus of Kordis, et al. would not be suitable for repeatably coupling a fiber optic probe to a tissue measurement site.
M. Kanne, Laser Mount Positioning Device and Method of Using the Same, U.S. Pat. No. 5,956,150; Sep. 21, 1999 describes a method for using an illumination device, such as a laser to align two components during an assembly process. The Kanne teachings are directed to a manufacturing process rather than optical sampling of tissue in vivo. The Kanne device does not provide any means for repeatably placing a probe guide at a tissue measurement site. It also has no way of monitoring the surface temperature at a tissue measurement site, or of minimizing surface temperature fluctuations and accumulation of moisture at a tissue measurement site.
D. Kittell, G. Hayes, and P. DeGroot, Apparatus for Coupling an Optical Fiber to a Structure at a Desired Angle, U.S. Pat. No. 5,448,662, Sep. 5, 1995 disclose an optical fiber support that is coupled to a frame for positioning an optical fiber at a desired angular position. As with the prior art previously described, the teachings of Kittell, et al. have nothing to do with optical sampling of tissue in vivo. Furthermore, the disclosed device allows an operator to immobilize an optical fiber so that it is maintained in a fixed position, but it does not offer a means of repeatably coupling a fiber optic probe to a tissue measurement site. It also has no way of monitoring the surface temperature at a tissue measurement site, or of minimizing accumulated moisture and temperature fluctuations at the site.
R. Messerschmidt, Method for Non-Invasive Blood Analyte Measurement with Improved Optical Interface, U.S. Pat. No. 5,655,530, Aug. 12, 1997 discloses an index-matching medium to improve the interface between a sensor probe and a skin surface during spectrographic analysis. Messerschmidt teaches a medium containing perfluorocarbons and chlorofluorocarbons. Since they are known carcinogens, chlorofurocarbons (CFC's) are unsuitable for use in preparations to be used on living tissue. Furthermore, use of CFC's poses a well-known environmental risk. Additionally, Messerschmidt's interface medium is formulated with substances that would be likely to leave artifacts in spectroscopic measurements.
It would be desirable to provide a placement guide for a fiber optic probe that coupled the probe to a tissue measurement site for in vivo optical sampling of the tissue. It would also be desirable to provide a means of assuring that the same tissue sample volume may be repeatably sampled, thus eliminating sampling errors due to probe placement. It would also be desirable to provide a way to minimize temperature fluctuations and disperse accumulated moisture at the tissue measurement site, thus eliminating further sources of sampling error. Additionally, it would be advantageous to provide a means of monitoring surface temperature at the tissue measurement site, therefore assuring that the temperature remains constant across repeated optical samples. Finally, it would be highly advantageous to provide an optical coupling fluid to provide a constant interface between a fiber optic probe and the skin at a tissue measurement site that is non-toxic and non-irritating and that doesn't introduce error into spectroscopic measurements.
SUMMARY OF THE INVENTION
The invention provides a fiber optic probe placement guide designed to provide repeatable sub-millimeter location accuracy on the skin surface of a tissue measurement site and a repeatable degree of tissue displacement. The major structural component of the fiber optic probe placement guide is a mount having a probe aperture, into which the fiber optic probe is inserted during use. The contact surface of the mount is curved to approximate the contour of the tissue measurement site, typically a site on a limb of a living subject. The mount incorporates structural features to minimize direct contact between the skin around the tissue measurement site and the contact surface in order to reduce temperature fluctuation and moisture accumulation at the site and on the probe, and to reproduce a small amount of tissue displacement in the vicinity of the tissue measurement site. The fiber optic probe placement guide has crosshair slots that are aligned with crosshairs at the tissue measurement site during repeated placements of the fiber optic probe placement guide in order to minimize optical sampling errors due to placement error. Guideposts on the exterior surface of the fiber optic probe placement guide fit into corresponding guidepost recesses on a subject interface bearing the fiber optic probe to facilitate alignment of the probe with the probe aperture.
During use, the fiber optic probe placement guide is fastened to the tissue measurement site using adhesive or straps. A subject interface bearing a fiber optic probe is directed toward the site; the guideposts are received by the guidepost recesses in the housing of the interface, and the probe is received by the probe aperture. An optical coupling fluid placed on the skin surface at the tissue measurement site eliminates sampling errors due to air gaps between the skin surface and the fiber optic probe.
The fiber optic probe placement guide is also equipped with a temperature probe so that skin temperature in the area directly adjacent the tissue measurement site may be monitored.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 provides a view of the contact surface of a fiber optic probe placement guide, according to the invention;
FIG. 2 provides a view of the exterior surface of the fiber optic probe placement guide of FIG. 1, according to the invention;
FIG. 3 illustrates the fiber optic probe placement guide of FIG. 1, in use. at a tissue measurement site, and a subject interface, according to the invention;
FIG. 4 illustrates an electrical connection between a temperature probe in the fiber optic probe placement guide of FIG. 1 and a subject interface unit, according to the invention;
FIG. 5 shows an alternate embodiment of a fiber optic probe placement guide, fabricated from a flexible layer and incorporating a reinforcing insert surrounding the probe aperture, according to the invention; and
FIGS. 6A-6C show a variety of alternate shapes for the fiber optic probe placement guide of FIG. 5, according to the invention; and
FIG. 7 shows a fiber optic probe and a tissue measurement site optically coupled by a layer of an optical coupling fluid.
DETAILED DESCRIPTION
In spectroscopic analysis of living tissue, it is often necessary to optically sample the same tissue volume repeatedly, using a fiber optic probe. Sampling errors can be introduced into these measurements because of the difficulty of repeatedly placing the fiber optic probe at the precise location used in preceding measurements, and repeatably producing the same amount of tissue displacement. With each small variation in the location of the probe, or the amount of pressure placed on the probe, a slightly different tissue volume is sampled, introducing sampling errors into the measurements. The invention provides a fiber optic probe placement guide to achieve the goal of highly repeatable fiber optic probe placement at a targeted tissue measurement site.
Referring now to FIG. 1, the fiber optic probe placement guide 10 with its contact surface 12 facing is shown. The major structural component of the fiber optic probe placement guide is a curved mount 11 . As shown, the contour of the contact surface 12 approximates the contour of a body part at a tissue measurement site, typically a limb of a living subject. While some contact between the concave contact surface 12 of the mount 11 and the tissue measurement site is unavoidable during use, structural features of the mount minimize direct contact between the contact surface 12 and the tissue measurement site. It is desirable to minimize contact between the skin in the vicinity of the tissue measurement site and the contact surface for two reasons:
The structural and chemical properties of the underlying tissue layers are affected by the surface temperature and the relative humidity at the tissue measurement site. Therefore, maintaining the tissue measurement site at a constant surface temperature and preventing accumulation of moisture reduces sampling errors.
Minimized contact decreases the amount of tissue displacement from pressure on the tissue from the mount, therefore minimizing sampling errors due to variations in tissue displacement;
The mount 11 is highly skeletonized by providing cutaway openings 13 . The surface area in direct contact with the tissue measurement site is further reduced by providing relieved areas 17 along the contact surface 12 .
The mount includes a probe aperture 14 for receiving a fiber optic probe. The probe aperture 14 is centered vertically and horizontally and penetrates the body of the mount 11 from the exterior surface 20 to the contact surface 12 . In the embodiment of FIG. 1, the probe aperture is rectangular to receive a rectangular fiber optic probe. However, the probe aperture may also be circular, hexagonal or triangular to receive probes of corresponding shape. The shape of the aperture should mimic the shape of the fiber optic probe it is to be used with, allowing them to fit together in a conventional male-female configuration. In order to monitor skin temperature within the vicinity of the tissue measurement site, a temperature probe 15 , such as a thermistor, is provided. The temperature probe should be in direct and intimate contact with the surface of the tissue measurement site in order to provide accurate temperature readings. Therefore, a temperature probe mount 16 is provided that protrudes from the relieved contact surface 12 of the mount 11 . In this manner, it is possible to maintain contact between the temperature probe and the tissue measurement site while still minimizing direct contact between the tissue measurement site and the contact surface 12 of the fiber optic probe placement guide. Furthermore, the temperature probe 15 is preferably located no more than 2mm from the edge of the probe aperture 14 in order to provide accurate temperature readings from within the immediate vicinity of the tissue measurement site.
FIG. 2 provides a view of the exterior surface of the fiber optic probe placement guide 10 . In the current embodiment, the exterior surface 20 is convex to correspond to the concave contact surface 12 . The exterior surface is equipped with two outwardly protruding guideposts 21 having substantially cylindrical bodies and conical terminations. The two guideposts are situated opposing each other such that each guidepost is positioned approximately midway between one end of the mount 11 and one end of the probe aperture 14 . Crosshair slots 22 are located at the midpoint of each of the four sides of the mount 11 .
FIG. 3 shows the fiber optic probe placement guide in use. The fiber optic probe placement guide 10 is placed over a tissue measurement site. Tissue measurement is generally performed on a limb of a living subject. However, other regions of the body provide suitable sites as well. Additionally, the invention would find application in optical sampling of excised tissue specimens or tissue measurement sites on cadavers. An adhesive layer 38 may be used to fix the position of the fiber optic probe placement guide. The adhesive layer may take the form of a double-sided pressure-sensitive adhesive pad placed between the skin and the probe placement guide, or in the case of a disposable version of the probe placement guide, the adhesive layer may be applied directly to the contact surface of the probe placement guide. The adhesive layer is the preferred means of fastening the probe placement guide because it minimizes tissue displacement caused by downward pressure on the skin by the probe placement guide. Alternatively, adhesive tape, or one or more straps having releasable fasteners may be used to secure the invention.
Using the crosshair slots 22 as a template, crosshairs are drawn on the subject's skin using a marking pen or some other suitable tool. Subsequently, the location of the fiber optic probe placement guide may be repeated with sub-millimeter accuracy by aligning the crosshair slots 22 with the crosshairs drawn on the subject's skin. A subject interface unit 30 includes a housing 31 bearing a fiber optic probe 33 . The fiber optic probe 33 protrudes from the interface side 37 of the housing 31 in a manner that allows it to be received by the probe aperture 14 , as indicated by arrow 35 . The housing 31 is also equipped with cylindrical guidepost recesses 32 , represented in dashed lines. An operator lowers the subject interface unit 30 toward the tissue measurement site, shown by the arrows 36 . As the interface unit 31 approaches the fiber optic probe placement guide, the guideposts 21 are received by the guidepost recesses 32 , as indicated by the arrows 34 , thus greatly facilitating the alignment of the probe 33 with the probe aperture 14 . After the probe is fully seated in the probe aperture, the guideposts provide a stable placement, thus minimizing possible sampling errors due to movement of the interface unit 30 during optical sampling, and also preventing damage to the probe 33 due to inadvertently rotating it within the probe aperture 14 during use. The guideposts also serve to limit downward motion of the interface unit, thereby preventing the operator from placing excessive downward pressure on the unit and introducing sampling error due to inconsistent tissue displacement.
An important additional function of the fiber optic probe is to correct tissue displacement by the probe placement guide. Before the fiber optic probe is seated within the probe aperture, the skin at the tissue measurement site bulges upward into the fiber optic probe aperture as a result of tissue displacement by the probe placement guide. During use, the gentle downward pressure by the fiber optic probe helps to correct the upward bulge of the skin, significantly reducing another source of sampling error from variations in tissue displacement. In order to achieve this correction, the termination of the fiber optic probe should be flush with the contact surface at the tissue measurement site when the fiber optic probe is fully seated.
The interface between the fiber optic probe and the skin surface at the tissue measurement site can also be a significant source of sampling error. Since the underlying tissue is not homogenous, the surface skin at the tissue measurement site may be uneven, with frequent irregularities. Coupling the relatively smooth surface of the fiber optic probe with the irregular skin surface leads to air gaps between the two surfaces. The air gaps create an interface between the two surfaces that adversely affects the measurement during optical sampling of tissue. As shown in FIG. 7, an amount of optical coupling fluid 71 between the fiber optic probe 33 and the skin of the tissue measurement site eliminates such gaps.
In a preferred embodiment, the optical coupling fluid is a perfluoro compound such as those known as FC-40 and FC-70, manufactured by 3M Corporation. Such compounds are inactive in the Near IR region, rendering them particularly well suited for optical sampling procedures employing Near IR spectra. Additionally, they have the advantage of being non-toxic and non-irritating, thus they can come into direct contact with living tissue, even for extended periods of time, without posing a significant health risk to living subjects. Furthermore, perfluoro compounds of this type are hydrophobic and are poor solvents; therefore they are unlikely to absorb water or other contaminants that will adversely affect the result during optical sampling. It is preferable that the optical sampling fluid be formulated without the addition of other substances such as alcohols or detergents, which may introduce artifacts into the optical sample. Finally, the exceptional stability of perfluoro compounds eliminates the environmental hazard commonly associated with chlorofluorocarbons.
Other fluid compositions containing perfluorocarbons and chlorofluorocarbons are suitable as optical coupling fluids: for example a blend of 90% polymeric chlorotrifluroethylene and 10% other fluorocarbons would have the desired optical characteristics. Chlorotrifluorethene could also be used. While these compositions have the desired optical characteristics, their toxicity profiles and their solvent characteristics render them less desirable than the previously described perfluoro compounds.
During use, a quantity of optical sampling fluid is placed at the interface of the tissue measurement site and the fiber optic probe so that the tissue measurement site and the fiber optic probe may be tightly optically coupled without leaving any air spaces between the two surfaces. In practice, one convenient way of placing the quantity of the optical sampling fluid at the interface between the tissue measurement site and the probe is to place a small amount of the fluid on the skin surface prior to placing the fiber optic probe, although it is easier to place it on the fiber-optic probe.
During use, the temperature probe 15 is electrically connected with the interface unit 30 by means of pin-and-socket electrical contacts. As FIG. 4 shows, the temperature probe 15 is connected to a pin electrical contact 40 embedded in the guidepost 21 . During use, the pin contact is received by a socket electrical contact 41 in the guidepost recess 32 , thus establishing an electrical connection between the temperature probe and the interface unit 30 . In this manner, electrical signals from the temperature probe are passed to processing components within the interface unit that convert the electrical signal into a temperature reading.
The current embodiment of the invention is preferably manufactured from a thermoplastic polymeric material such as ABS or polytetrafluoroethylene (PTFE) using a conventional injection molding process.
Other advantageous embodiments of the invention are possible. For example, the previously described embodiment is manufactured from a non-porous polymeric material, rendering it suitable for shorter periods of use, where the possible impact on the temperature and humidity at the tissue measurement site is not of great concern. An alternate embodiment, particularly well suited for longer periods of use, employs a layer fabricated from a flexible, breathable material such as GORE-TEX, manufactured by W. L. Gore and Associates, as the mount. As shown in FIG. 5, the layer incorporates a reinforced insert 50 around the probe aperture to lend the aperture the requisite structural stability. As shown in FIGS. 6A-6C, the mount may assume a circular, or oval or polygonal shape.
While previously described embodiments of the invention employ structural features to control temperature and humidity at the tissue measurement site passively, an alternative embodiment incorporates an airflow device, such as a small blower, to evaporate moisture from the fiber optic probe, the contact surface, and the tissue measurement site.
Further alternative embodiments of the invention employ three and four guideposts, respectively, along with corresponding guidepost recesses.
While the invented fiber optic probe placement guide allows highly repeatable probe placement at a targeted tissue measurement site, the invention may also be used to produce small sampling variations in a controlled manner by shifting the placement of the fiber optic probe in known increments across successive optical samples.
The invented fiber optic probe placement guide has been herein described in relation to optical sampling of tissue. One skilled in the art will appreciate that the invention may be applied in other settings requiring repeatable placement of a fiber optic probe.
The invention provides a means of limiting sampling errors during in vivo spectroscopic examination of tissue samples by providing highly repeatable fiber optic probe placement at a targeted tissue measurement site. Structural features of the invention minimize temperature fluctuations and accumulation of excess humidity at the tissue measurement site and on the fiber optic probe, and variations in tissue displacement, all sources of sampling error. A temperature probe in direct contact with the skin surface at the tissue measurement site allows the monitoring of skin temperature across successive measurements. An optical coupling fluid eliminates air spaces at the interface of the skin surface of the tissue measurement site and the fiber optic probe.
Although the invention is described herein with reference to certain preferred embodiments, one skilled in the art will readily appreciate that other applications may be substituted for those set forth herein without departing from the spirit and scope of the present invention. Accordingly, the invention should only be limited by the claims included below. | A fiber optic probe placement guide minimizes sampling errors during optical sampling of a tissue measurement site by allowing repeatable placement of the fiber optic probe at a targeted tissue measurement site. A mount, contoured to conform to the shape of the tissue measurement site, typically the arm of a human subject, contains an aperture for receiving a fiber optic probe. A temperature probe on the contact surface of the guide allows for monitoring of surface temperature within the vicinity of the tissue measurement site. Crosshair slots in the mount align with corresponding crosshairs at the tissue measurement site. The fiber optic probe placement guide is affixed to the tissue measurement site by means of adhesive tape or fastenable straps. Guideposts on the external surface of the mount are received by corresponding receptacles on a subject interface bearing the fiber optic probe to facilitate alignment of the fiber optic probe with the aperture. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to an electronic pressure responsive switch that can find particular application as a measuring member for sensing pressure fluctuations in textile machines. The pressure responsive switch is provided with a sensor component such as a proximity sensor (proximity switch member), an elastic diaphragm and an activating element adapted to move into the effective range of the sensor component.
U.S. Pat. No. 4,211,935 issued July 8th, 1980 discloses an electronic pressure responsive switch that comprises an axially displaceable electronic proximity sensor (proximity switch member), a metal plate-equipped diaphragm oriented perpendicularly to the axis of and arranged spaced from, the proximity sensor. The pressure responsive switch according to the patent further has a compression spring which is arranged coaxially about the proximity sensor and has an end which engages the metal plate. In a pressure responsive switch of this type, with increasing outer pressure applied against the metal plate-equipped diaphragm the compression spring yields so that upon reaching a predetermined setting pressure the metal plate enters into the operational (switching) zone of the electronic proximity sensor. Upon this occurrence, the thyristor forming part of the proximity sensor fires and applies a voltage to the output of the switch. As the pressure drops below a predetermined switch-on pressure, the thyristor opens, and as a result, the voltage at the switch output disappears. The electronic pressure responsive switch is a component of a regulating system in which the diaphragm forms the measuring member and the electronic proximity sensor forms the regulator of the system. It is a drawback of the above-outlined electronic pressure responsive switch that solely a two-point regulation may be effected therewith, that is, for example, in case of exceeding or dropping below a certain predetermined pressure, on-switching or off-switching takes place.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved electronic pressure responsive switch of the above-outlined type with which a more than two-point regulation is possible and wherein such regulation is achieved by simple structural means.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, there are provided at least two sensors on the same side of the diaphragm and that each sensor is associated with at least one activating element.
By means of the invention as outlined above, it is feasible to provide, in a pressure dependent control system, an electronic pressure responsive switch with more than two switching points. The pressure responsive switch according to the invention may be of robust structure, it can operate with a high switching frequency and is insensitive to dust. As sensor members, for example, inductive proximity sensors, optical barriers, light diodes (infrared photocells), supersonic sensors and the like may be used.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic axial view of a preferred embodiment of the invention.
FIG. 1a is a schematic axial view of another preferred embodiment of the invention.
FIG. 2 is a schematic axial view of still another preferred embodiment of the invention.
FIG. 3 is a schematic axial view of a further preferred embodiment of the invention.
FIG. 4 is a schematic axial view of still another preferred embodiment of the invention.
FIG. 5 is a schematic axial view of a further preferred embodiment of the invention.
FIG. 6 is a schematic top plan view of one part of the structure shown in FIG. 5.
FIGS. 7a; 7b and 7c are schematic top plan views of a component of the FIG. 5 structure, depicting different switching stages.
FIG. 8 is a schematic view of a variant of the component shown in FIGS. 7a through 7c.
FIG. 9 is a schematic axial view of still another preferred embodiment of the invention.
FIG. 10 is a schematic view of a component of the FIG. 9 structure.
FIGS. 11a, 11b and 11c are schematic top plan views of a component of the FIG. 9 structure, depicting different switching stages.
FIG. 12 is a schematic top plan view of a variant of the component shown in FIGS. 11a through 11c.
FIG. 13 is a block diagram illustrating the invention incorporated in a control circuit.
FIG. 14 is a block diagram illustrating the invention incorporated in a different type of control circuit.
FIG. 15 is a schematic side elevational view illustrating the invention incorporated in a pneumatic fiber tuft supply apparatus.
FIG. 16 is a schematic side elevational view illustrating the invention incorporated in a conveying duct which advances fiber tuft to a pneumatic tuft feeding system.
FIG. 17 is a block diagram showing further details of the control circuit of FIG. 13.
FIG. 18 is a block diagram showing further details of the control circuit of FIG. 14.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to FIG. 1, there is shown a preferred embodiment of an electronic pressure responsive switch 1 according to the invention, having a rotationally symmetrical housing 2, one face of which is closed off by a diaphragm 3 made, for example, of rubber. Between the diaphram 3 and a rear wall 2a of the housing 2 there is arranged a compression spring 4 engaging the inner face of the diaphragm 3. Within the housing 2 there are provided two proximity switch members 5 and 6 which function as sensors and which may be, for example, of the inductive type. On the inner face of the diaphragm 3 there are provided, as activating elements, two metal plates 7 and 8 which are coaxial with respect to the proximity sensors 5 and 6. The diaphragm 3 is at different distances from the end faces 5a and 6a of the respective proximity sensors 5 and 6, while the diaphragm 3 is equidistantly arranged with respect to the frontal faces 7a and 8a of the respective metal plates 7 and 8. To the sides 5b and 6b of the respective proximity sensors 5 and 6 there are connected respective terminal wires 5c and 6c which are brought to the outside of the rear wall 2a of the housing 2. The proximity sensors 5 and 6 are axially displaceable, whereby the tolerance field between the end faces 5a and 7a as well as 6a and 8a may be increased or decreased. In the embodiment illustrated in FIG. 1a, the pressure responsive switch 1a has a single activating element formed of a metal plate 7' which serves both sensors 5 and 6. The activating element 7' is mounted on the inner face of the diaphragm 3.
Turning now to the embodiment illustrated in FIG. 2, the switch 1b has a diaphragm 3 which is at the same distance from the end faces 5a and 6a of the respective proximity sensors 5 and 6, but which is at different distances from the end faces 7a and 8a of the metal plates 7 and 8.
Turning now to the embodiment illustrated in FIG. 3, the proximity sensors 5 and 6 of the switch 1c are mounted on the diaphragm 3 whereas the activating elements 7 and 8 are secured to the housing 2. The diaphragm 3 is at different distances from end faces 5a and 6a of the proximity sensors 5 and 6, whereas the diaphragm 3 is equidistantly spaced from the end faces 7a and 8a of the respective activating elements 7 and 8.
Turning now to FIG. 4, in the embodiment shown therein, the switch 1d differs from the FIG. 3 embodiment in that the diaphragm 3 is equidistantly spaced from the end faces 5a and 6a of the proximity switch members 5 and 6, whereas the diaphragm 3 is at different distances from the end faces 7a and 8a of the respective activating elements 7 and 8.
Turning now to the embodiment illustrated in FIG. 5, there is shown an electronic pressure responsive switch 1e in which the longitudinal axes of the proximity sensors 5 and 6 are parallel to the plane of the diaphragm 3. The activating element 10 is oriented perpendicularly to the diaphragm 3 and to the longitudinal axes of the proximity sensors 5 and 6 and is secured at its end 10a to the inside face of the diaphragm 3. The other end 10b of the activating element 10 is adapted to penetrate into the operational range of the end faces 5a and 6a of the respective proximity sensors 5 and 6, dependent upon the magnitude of the pressure exerted on the outer face of the diaphragm 3. In this manner the proximity sensors 5 and 6 are actuated as a function of the pressure. The proximity sensors 5 and 6 are mounted on an adjusting bracket 11 coupled to a setting mechanism 12 which is supported in the switch housing 2. The setting mechanism 12 is provided with a fine pitch winding 12a received in a complementally threaded sleeve 12b whereby the basic distance between the diaphragm 3 and the proximity sensors 5 and 6 may be altered as indicated by the arrow A.
Turning now to FIG. 6, the adjusting bracket 11 has two securing slots 11a and 11b for the respective proximity sensors 5 and 6. Dependent upon the arrangement of the proximity sensors 5 and 6 in the adjusting bracket 11, the pressure threshold at which switching should occur, may be varied or, as the case may be, can be determined in advance as a fixed value.
In the description which follows, the operation of the pressure responsive switch according to the invention will be set forth with reference to FIGS. 7a, 7b and 7c.
It is assumed at the outset that the pressure responsive switch is to effect a pressure-dependent motor control by means of the following three pressure-dependent switching states: (a) the motor is deenergized; (b) the motor runs slow and (c) the motor runs fast.
As shown in FIG. 7a, both proximity sensors 5 and 6 are actuated since, by virtue of a deflection of the diaphragm 3 to a certain position in response to a particular external pressure, activating members 7 and 8 have both entered in the operational zone of the respective proximity sensors 5 and 6. This condition results in a de-energization of the motor controlled by the pressure responsive switch. In the switching state illustrated in FIG. 7b only the proximity sensor 5 is activated, resulting in a slow run of the motor. In the position shown in FIG. 7c, neither the proximity sensor 5 nor the proximity sensor 6 is activated, this results in a fast run of the motor.
By means of the distance between the proximity sensors 5 and 6, it can be determined exactly at what pressure should the motor be switched to slow run or switched off. By means of an adjusting mechanism, such as the adjusting bracket 11 and the setting device 12 of the FIG. 5 embodiment, the basic distance between sensor and activating element may be changed synchronously, that is, the pressure value at which switching occurs may be varied. If it is required to include a fourth switching point in the system with which the electronic pressure responsive switch according to the invention is associated, an apertured activating element is designated at 7" in FIG. 8 is advantageously used. In principle, with such a structure a desired number of switching points may be achieved in accordance with the formula n=2 x , where n is the number of switching points and x is the number of sensors. The evaluation of the signals transmitted by the sensors is performed by simple electronic circuitry known by itself. It is feasible to include in such circuit desired time-delay components so that a "fluttering" is suppressed to thus prevent a continuous back-and-forth switching between slow and fast motor run.
Turning now to FIG. 9, there is shown a preferred embodiment of the electronic pressure responsive switch designated at 1f which comprises two light barriers functioning as sensors. One light barrier (optical sensor) comprises a transmitter 13 and a receiver 14 while the other light barrier comprises a transmitter (light source) 15 and a receiver (detector) 16. The axis between the transmitter and the receiver of each light barrier extends parallel to the plane of the diaphragm 3. An activating element 10' extends perpendicularly to the diaphragm 3 and is affixed to the inner face thereof by means of an end 10a'. The other end 10b' may be placed in an active or inactive position between one or both optical barriers dependent upon the magnitude of pressure exerted on the outer face of the diaphragm 3.
FIG. 10 illustrates the structure of the activating element 10'. It essentially comprises a transparent rectangular plate member provided with spaced opaque strips 17a, 17b and 17c extending transversely to the direction of displacement of the activating member as the diaphragm 3 undergoes deformation in response to an external pressure applied thereto. Dependent upon the shifted position of the activating member 10', the light beam between transmitters and receivers of the respective optical barriers is interrupted or allowed to pass, whereby the respective optical barriers generate "light" or "dark" signals in a predetermined pattern. In the embodiment shown in FIG. 10 the diaphragm 3 is at different distances from the two optical barriers 13, 14 and 15, 16 whereas the diaphragm 3 is at the same distance from any one of the opaque strips 17a, 17b and 17c.
Turning now to FIGS. 11a, 11b and 11c, there is illustrated the structure of a modified activating member 10" of the embodiment illustrated in FIG. 9. The activating element 10" comprises a transparent rectangular carrier which has two opaque fields 17a and 17b with alternating clear (transparent) fields 18a, 18b in between. It is noted that the alternating light and dark fields may be obtained by using a black-and-white film strip replaceably sandwiched between two transparent plates. As it may be observed in comparing the various positions of the activating member 10" in respective FIGS. 11a, 11b and 11c, the light beams between the transmitter and the receiver of the respective optical barriers may be interrupted or allowed to pass through. The signals generated by the respective optical barriers dependent upon the position of the activating member 10" is evaluated in a circuitry shown, for example, in FIG. 14, as will be described later as the specification progresses. By the widths of the fields the desired switching points may be predetermined. By means of an externally accessible setting device the optical barriers 13, 14 and 15, 16 can be displaced (adjusted) as a unit, so that the entire pressure level in which the switching points should lie may be set. Each transition from a transparent field to an opaque field, and conversely, represents a switching point. The smaller the distance between the fields on the activating element 10", the more switching points may be obtained. The optical barriers 13, 14 and 15, 16 are of different distances from the diaphragm 3 in FIGS. 10, 11a, 11b and 11c so that the electronic evaluating circuit associated with the optical barriers is capable of recognizing a direction of displacement (forwards or rearwards displacement recognition) to thus sense an increasing or decreasing pressure. Transitions (from light to dark and from dark to light) which are counted and which, because of the positioning of the light barriers, cannot occur simultaneously, are decisive for the direction detection.
The different operating states corresponding to FIGS. 11a through 11c (such as de-energized, slow and fast states) are effected as a result of evaluating the transitions (from light to dark and conversely). Although, for example, light barriers 13, 14 and 15, 16 in FIGS. 11a through 11c are disposed in a dark field, the number of transitions to reach these dark fields is different.
The embodiment shown in FIGS. 11a, 11b and 11c can, similarly to the embodiment according to FIGS. 7a, 7b and 7c operate with three switching points. Thus, in the position shown in FIG. 11a, the motor is switched off, in the position shown in FIG. 11b the motor runs slow and in the position shown in FIG. 11c the motor runs fast.
FIG. 12 shows another modified activating element 10'" wherein the diaphragm 3 has the same distance from the two light barriers 13, 14 and 15, 16 but wherein the diaphragm 3 is at different distances from the associated opaque fields 17d through 17i.
Turning now to FIG. 13, the two sensors 5 and 6 of the switch 1 of FIG. 1 are connected to the inputs of an evaluating circuit 18 which may have electric elements such as relays, amplifiers or the like. The outputs of the circuit 18 are connected to a pole-reversible asynchronous motor 19 which has three possible operational states, namely OFF, fast run and slow run states. The circuit 18 may also be used, for example with a switch according to the FIG. 5 embodiment.
Turning now to FIG. 14, the two optical barriers 13, 14 and 15, 16 of the FIG. 9 embodiment are connected to inputs of an electronic counting circuit 20 which in turn is connected to an electronic motor control 21 which may be a SIMOREG model, manufactured by Siemens AG, Munich, Federal Republic of Germany. The motor control 21 is, in turn, coupled to a d.c. motor 22. With the circuitry shown in FIG. 14 it is feasible to assign in a simple manner predetermined time periods to the switching points whereby desired hysteresis conditions can be obtained. In this manner a "flutter" effect, such as a continuous back-and-forth switching between slow run and fast run is prevented.
FIG. 15 illustrates a textile machine combined with the electronic pressure responsive switch according to the invention. Thus, as shown in FIG. 15, textile fiber tufts are introduced from a fine opener by means of a supply and distributor duct 23 into an upper reserve chute 24. From the reserve chute 24 the fiber tufts are admitted to a feed roller 25 and an opening roller 26 which advance the material to a lower feed chute 27. The feed chute 27 supplies the textile fiber tufts as a fiber lap to a carding machine generally designated at 28. On a wall of the lower feed chute 27 there is mounted the electronic pressure responsive switch according to the invention (for example, the switch 1 according to the FIG. 1 embodiment). The switch 1 is operatively connected, by means of a regulator 29, with the drive motor 30 of the feed roller 25. During operation, the electronic pressure responsive switch measures the pressure in the lower feed chute 27. From the measured pressure an electric signal is derived which represents a regulating magnitude. The signal generates, by means of the regulator 29, a setting signal which is applied to the motor 30 of the feed roller 25. By varying the rpm of the feed roller 25 as a function of the pressure fluctuations in the feed chute 27 (multipoint regulation), the flow rate of the fiber tuft in the feed chute 27 is altered.
Turning now to FIG. 16, there is shown in schematic side elevation a fiber tuft feeding system. The intake side of a tuft propelling fan 31 is connected to a fine opener 32. To the pressure side of the fan 31 there is connected the supply and distributor duct 23 which is arranged above the reserve chutes 24 of a series of fiber tuft feeding apparatuses of the type shown in FIG. 15. The electronic pressure responsive switch 1 according to the invention is mounted on the wall of the distributor duct 23, above the first reserve chute 24, as viewed from the impeller 31. The fan 31 draws the opened fiber material from the last beater station of the fiber opening system, for example, from the fine opener 32 and delivers the material by means of conveying air stream in the supply and distributor duct 23 to the reserve chutes 24 of the adjoining card feeding apparatuses. Upon entrance of the tuft-air mixture into the reserve chutes 24, the air escapes through conveying air outlet openings (not shown) such as a filter and the tufts are delivered into the reserve chutes 24 where they form tuft columns. As the tuft columns begin to rise and thus begin to cover the transport air outlet filter, the pressure in the supply and distributor duct 23 increases. This pressure increase continues as the column height in the reserve chutes 24 increases and eventually attains its maximum value which corresponds to the preselected switching pressure when the transport air outlet filters are entirely covered by the fiber tuft column in all the reserve chutes 24.
At the beginning (upstream end) of the supply and distributor duct 23, above the first reserve chute 24, there are arranged a fine pressure sensor 33 to indicate the pressure in atmospheres and the electronic pressure responsive switch 1 for switching the material supply on or off or switching from one speed to another at which the tuft material travels from the fine opener 32 to the fan 31. The electronic pressure responsive switch 1 is set to a predetermined speed switchover and switch-off pressure. If these pressures are reached during operation, the material feed from the fine opener 32 is switched to slow run or is switched off altogether. In this manner, the fiber supply to the fan 31 is decreased or shut off. The fan 31 remains in operation and, if supply shutoff has occurred, it drives exclusively air into the supply and distributor duct 23 and maintains the pressure conditions therein. As the feed chutes 27 need additional material, fiber tuft is drawn by the feed rollers 25 from the reserve chutes 24. Thus, the fiber tuft columns in the reserve chutes 24 are gradually depleted. As a result, the transport air outlet filters gradually are freed and consequently the pressure in the duct drops. As the pressure drop reaches the switching point pressure values preset in the electronic pressure responsive switch 1, the tuft delivery from the fine opener 32 is again switched on or switched over from a slow run to a fast run. As a result, the fan resumes delivery or increases delivery of fiber material to the reserve chutes 24.
The electronic pressure responsive switch 1 is connected with an electric drive motor 35 with the intermediary of a regulator 34 which may include a time relay. The drive motor 35 rotates an opening roller, such as a Kirschner beater, in the fine opener 32 by means of a settable gear drive (not shown).
In the examples described in connection with FIGS. 15 and 16, the electronic pressure responsive switch 1 affects the feed roller 25 (FIG. 15) or the fine opener 32 (FIG. 16) of a cleaning line. As an alternative, the electronic pressure responsive switch 1 may affect other setting members of the cleaning line to vary the delivered quantity of the fiber tufts. The electronic pressure responsive switch 1 may find application in any fiber tuft feed system for textile machines; it may be used, for example, in a box feeder for beaters, such as a Pneumafeeder model, manufactured by Trutzschler GmbH, Monchengladbach, Federal Republic of Germany.
Turning now to FIG. 17, there is shown a schematic representation of the structure of the electronic evaluating circuit 18 of FIG. 13. Sensors 5 and 6 are connected with a demultiplexer 36, e.g. type 74 C 154 made by National Semiconductor Corporation. Each one of the outputs of demultiplexer 36 is connected with one of amplifiers 37a, 37b, 37c and 37d and the latter are connected with respective relays 38a, 38b, 38c and 38d. Conductors 39a, 39b, 39c and 39d extending from evaluating circuit 18 form four switching points.
FIG. 18 is a schematic representation of the structure of the electronic counting circuit 20 of FIG. 14. The light barriers 13, 14 and 15, 16 are connected with a known counting direction detecting device 40 from which leads a conductor 41 for the counting pulse and a conductor 42 for the counting device of a counter 43. The latter is connected by three conductors with a demultiplexer 44 which may be of the same type as the demultiplexer 36. Conductors 45a through 45h extending from demultiplexer 44 form eight switching points. The cable shown in FIG. 14 between counting circuit 20 and control device 21 may have, for example, eight conductors.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | An electronic pressure responsive switch comprises an activating element and at least two sensors. The activating element and the sensors are arranged to be relatively displaceable with respect to one another whereby the sensors each generate signals when the activating element assumes a predetermined position relative to a respective sensor. The switch further has an elastic diaphragm having a first face exposed to pressure to be sensed and a reverse second face carrying either the activating element or the sensors. The diaphragm is deformable by the pressure whereby the relative position between the activating element on the one hand and the sensors on the other hand is varied as a function of the pressure. | 6 |
RELATED APPLICATION
This application is a continuation-in-part of my copending application: U.S. Ser. No. 502,630, filed Sept. 3, 1974, entitled: METHOD AND DEVICE FOR APPLYING GLUE TO FIBER MATERIAL: Inventors: Hermann Forster et al which application is now abandoned.
The present invention relates to an apparatus for applying glue to fibers of wood, bagasse or the like, in particular cellulose containing substances in which glue is added to fibers being moved whereupon the mixed substance is kept in movement for distributing the glue.
BACKGROUND OF THE INVENTION
Heretofore known devices for applying glue to fibers, according to which a shaft centrally arranged in a drum-shaped mixing chamber, has tools rotating thereon in the operating range of which the mixed substance passes after glue has been added, are employed for applying glue to fibers as well as to chips or the like. The design of these heretofore known machines is based on the finding that for purposes of obtaining a homogeneous mixture a particularly well distributed addition of the glue is of less importance than a fast homogenization of the mixed substance after the addition of glue by moving the chips or the like under a moderate pressure relative to each other. Such chip movement will cause the glue which is supplied to the chip material to become distributed uniformly in the material.
For purposes of obtaining the wiping effect between particles or fibers of the material which will result in uniform distribution of the glue thereon, the tools in the mixing zone adjacent the glue applying zone are in most instances provided with front surface portions of substantial area which are inclined toward the advancing direction and which, while the mixing substance is being agitated, exert a moderate pressure on the material and thus press the particles against each other.
Due to the simultaneously generated relative movements between the particles, an intensivewiping of the glue therebetween will be realized. During the agitation of the material being mixed, those particles which are adjacent the tool slide along the inclined surface parts of the tool while due to the lateral deviation of the adjacent particles relative to the advancing direction of the tools, the pressure required for an intensive wiping effect is generated in the adjacent mixed substance. Under the influence of this pressure, the adjacent material starts moving and escapes toward the side while, however, the pressure in the material by a correspondingly long design of the inclined sliding surfaces on the tool can be maintained also during this escaping movement.
Therefore, an intensive wiping of the glue by friction within the material requires distinct sliding operations of the material along the tool so that such tools in their range of operation may heat up and may have to be cooled by special cooling operations.
While with apparatus of the nature described, a uniform application of glue to chips and particles and the like can be obtained in such a manner so that it becomes possible to produce veneer or plywood plates of high qualities, experience has shown that fiber plates produced from fibers to which the glue has been applied in this manner have properties which reduce the quality.
More specifically, such fiber plates contain a plurality of brittle glue enclosures in the form of nests or spots. The felting of the individual fibers in the plates as it is desired in order to obtain high strength, is harmfully effected by ball-shaped rolled up agglomerates which are created by tools on the shaft having broad surface areas which engage the mixture of glue and fibers. Furthermore, such plate contains enclosures of quantities of fiber particles which have received too much glue and are compressed to a too-great extent and, in addition thereto, have the fibers oriented in one direction, said quantities of fiber particles having been formed by the formation of deposits on machine parts of the glue applying device.
Such faults in the fiber plate are all the more serious since such fiber plates, due to their homogeneous felted and layer-free texture, may be qualitatively particularly high-grade plates and may be particularly solid and well machinable. The above-mentioned faults, when occurring in the finished fiber plate, reduce, however, the important fundamental advantages of a fiber plate so that such fiber plates heretofore could frequently not be used because it was not possible to manufacture the same substantially free from faults and in an economical manner.
Experience has shown that glue-fiber agglomerates are formed by the friction and wiping effect which is favorable for the application of glue to the chips, and it was, furthermore, found that heretofore known machines and tools due to their flat design offer too much sliding and rolling-up surfaces to the fiber-glue mass. Due to the distinctive sliding movement between the mixed substance and the sliding surfaces of the tool which sliding movement and sliding surfaces are necessary for obtaining a good intermixture of the glue during the application of the glue to the chips, the fibers containing a high proportion of glue are held in this position.
This brings about the formation of ball-shaped rolled-up glue-fiber agglomerates with frequently too high a proportion of glue. On the other hand, a wiping of the glue within the adjacent regions of the material occurs only to a rather limited extent so that the glue enclosures are not broken up.
The problem underlying the present invention consists in so designing the glue application of the above-mentioned general type that a rolling-up or a formation of nests in the fiber material after the addition of glue will be avoided.
BRIEF SUMMARY OF THE INVENTION
The problem underlying the present invention has been solved in conformity with this invention by subjecting the mixed substance in a forward driving device to pulses acting point-wise or along lines. In this way, distinct frictional operations with large surface contact are avoided, and the mixed substance is, while minimizing the occurring frictional effects, subjected to a moving process which brings about a low pressure intermixture.
The point-wise or line-wise effect of the pulses not only avoids a distinct surface contact and thus the disadvantageous frictional operations inherent thereto, but at the same time brings about a fine combing of the material whereby glue-fiber agglomerates which might form are immediately separated.
A device according to the invention for applying glue to fibers of wood, bagasse, or the like, especially cellulose-containing substances, comprises, in conformity with machines employed for applying glue to the chips, a shaft which is centrally arranged in a drum and which is equipped with radial tools. The fibrous material is introduced into one end of the drum and is first subjected to the action of driver elements which move the material toward the other end of the drum which is provided with a discharge opening.
After the addition of glue, the material moves into the range of action of said tools while, however, the tools are in conformity with the invention designed in the shape of tools which taper inwardly in a direction away from the shaft somewhat like needles. The thickness of the needle-shaped tools is at least in the region close to the wall, for generating the point-wide or line-wise pulses, selected below 5mm, preferably even below 3mm.
The tools may be thin and steel, especially spring steel, is particularly suitable for such tools.
For purposes of obtaining locally differentiated action of the needle-shaped tools upon the material, the tools may, according to a preferred design of the invention, be bent out of the radial direction at least in the region close to the wall of the drum. If the tools are bent off in the direction of movement of the tools at the ends thereof close to the wall, the material is subjected to a radial inwardly directed component and the material close to the wall will be deviated in the direction toward the interior of the mixing chamber, while, furthermore, the frictional contact of the material with the wall of the drum will be reduced.
By correspondingly selecting the number of the mixing tools and, in particular, the axial spacing thereof on the mixing shaft, which spacing according to a preferred embodiment of the invention should be less than half, preferably less than a third of the inner diameter of the mixing chamber, it is possible, also, with a certain preselected circumferential speed of the tools, to prevent the material from forming in the drum which may be desired when applying glue to chips.
In this way, the intensity of the frictional contact of the mixed material with the drum wall will be reduced further so that a rolling up or an agglomerating of the mixed material into clumps not only on the tools, but also on the drum wall, will be prevented to a major extent.
Also, compacted or agglomerated clumps in the material, and which have a relatively greater weight-volume ratio, are centrifuged into the radially outer region of the drum where they pass into the region of the ends of the tools, which are bent off in particular in the direction of rotation, and are intensively beaten by the higher tool speed prevailing in the radially outer regions and are thus split up.
It is, therefore, an object of the present invention to produce substantially fault-free fiber plates or the like bodies of fiber material and to do so economically.
The exact nature of the present invention will become more clearly apparent upon reference to the following detailed specification taken in connection with the accompanying drawings in which:
FIG. 1 illustrates a longitudinal section through a glue applying device according to the invention.
FIG. 2 represents a cross section taken along the line II--II of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawing in detail, the glue applying device according to the present invention diagrammatically illustrated in FIGS. 1 and 2 comprises a longitudinally extending cylinder shaped mixing chamber or drum 1 having coaxially arranged therein a mixing shaft 2. At the right hand end (with regard to FIG. 1) of the mixing chamber 1 there is provided an inlet chute 3 through which fiber material may be introduced from above into the mixing chamber 1.
In this axial region of the chute 3, the mixing shaft 2 is equipped with specially designed intake tools 4 which subject the fiber material to rotation and convey the same in axial direction to the outlet chute 5 which is located at the left hand of drum 1 as it is seen in FIG. 1.
Under the influence of this conveying movement, the fiber material first passes into a glue applying zone 6 in which the glue is applied to the fibers. According to the invention, a glue feeding pipe 7 is provided in the interior of the mixing shaft 2. The pipe 7 is in the axial region of the glue applying zone 6 at its circumference provided with glue exit openings 8, through which the glue can enter the interior of the hollow mixing shaft 2 and by a centrifugal effect can form a film on the inner wall of the mixing shaft 2.
From the inner chamber of the mixing shaft 2, the glue passes into feeding passages 10 and into glue adding tubes which radiate from the mixing shaft 2. From here the glue passes by centrifugal effect radially outwardly up to and into the head range of the feeding tubes 9, from where the glue passes through exit openings 11 and into and on the fiber material.
Instead of the aforementioned addition of glue from the interior, it is also possible to introduce the glue through feeding tubes into the fiber material, said feeding tubes passing from the outside through the wall of the mixing chamber 1. It is merely essential for the invention that following the introduction of the glue into the mixing chamber 1, in a glue applying zone similar to the zone 6, glue is added which is thereafter distributed as homogeneously as possible in a mixing zone 12 of the drum 1 while a rolling up and an agglomeration of the fibers is to be avoided.
In contradistinction to the heretofore known chip gluing machines in which in the mixing zone wide, for instance paddle-shaped mixing tools are provided for generating a friction at limited pressure in the mixing zone, the mixing shaft 2 in the mixing zone 12 is, in conformity with the invention, equipped with needle-shaped tools 13 which may be spring steel. The tools 13 have a thickness of a few millimeters, for instance from 1 to 3 mm, at least at the radially outer ends, so that they impart to the mixed material substantially point or line shaped pulses.
The tools 13 may be designed as slender needle wires and arranged in axially spaced relationship to each other in respective planes while in one plane there may, for instance, be uniformly distributed from four to twelve tools 13 and arranged at the circumference of the shaft. As will be seen, in particular, from FIG. 2, in the present embodiment referred to above, six tools 13 are arranged in a frame while, however, in conformity with the requirements of the individual case also a greater or smaller number may be provided and, in particular, the tools 13 of adjacent planes need not be located in the same radial plane.
The rotational speed of the mixing shaft 2 may, in this connection, be adapted to an optimum operation of the intake tools 4 and/or in conformity with the requirements in the gluing zone 6. The forward driving power in circumferential direction conveyed by the tools 13 onto the mixing material may be corresponding selection of the number of tools 13 and the distance a between their planes be so selected that within the region of the mixing zone 12 no closed compact ring of material will form at the inner circumference of the cylindrical wall of mixing chamber 1.
Instead, a ring of material formed approximately in the gluing zone 6 will be at least partially broken up. Because the ring of material is not compact, the tools 13 do not only become effective at their radial outer end but comb or fray the rotating fiber material over a major region of their length. The number of the tools 13 arranged in one plane may, while considering the speed of the mixing shaft 2 and of the axial conveying speed of the fiber material, be so selected that a sufficiently great proportion of the fiber material will, with each axial passage through a plane of the mixing tool 13, receive a sufficient number of fine pulses and will thus be intensively combed or frayed.
As illustrated in FIG. 2, the mixing tools 13 have their radial outer ends provided with a cranked, or bent, portion 15 pointing into the advancing direction indicated by the arrow 14. This crank portion 15 imparts upon the fiber material in the wall-near zone impulses which are directed away from the cylindrical wall of the mixing chamber or drum 1 so that the sliding of the fiber parts or components centrifuged against the wall will be prevented.
Due to this specific step for influencing the impulse direction in the wall-near region and to influence the forward driving power conveyed to the mixed material within the region of the mixing zone 12, which driving powder prevents the generation of a massive wall-near ring of material, a rollingup or agglomeration will be prevented by sliding friction on the wall of the mixing chamber 1.
In the radially outer range of the crank portion 15 of the tool 13, the average or mean rotary speed of the tools 13 is greatest and also the oscillatory movement in view of the resilient design of the tools so that here particularly strong pulses occur. These strong pulses in the radial outer range favor a beating-up of clumps of fiber and glue which might occur and which, due to their relatively high weight-volume ratio, are centrifuged out in the wall-near region and are here effectively diminuted and separated.
As will be evident from the above, the fiber material on its way from the gluing zone 6 to the discharge chute 5 is, by the machine according to the invention, intermixed substantially without pressure and friction and is continuously exposed to individual fine impulses which maintain, on one hand, a loose rotary movement of the fiber material and, on the other hand, see to it that a continuous separation or splitting up will occur of any agglomerates or the like which may form.
By means of the needle-like design of the tools 13, the fiber material is continuously combed through and beaten so that a rolling-up of the fibers and the formation of piles of fibers and of agglomerations by local felting or the like as well as the formation of deposit on the tools 13 or on the walls of the mixing chamber 1 will be avoided. The mixed material to which the glue has been applied thus will, in a homogeneous form, pass to the discharge chute 5. However, the individual fibers will, due to the wobbling rotary movements of the material, especially within the regions between the planes of the tools 13, not be oriented in the same direction but will be located at random and in loose condition.
In contrast to the heretofore known gluing machines, the discharge chute 5 is not closed by a dosing spring loaded plate because due to the only loose rotary movement in the interior of the mixing chamber 1, no sufficient pressure will be exerted upon such plate. A gluing device according to the invention thus comprises an open discharge chute 5 while the dosing may be effected by suitable adjustment of the axial delivery of the intake tools 4 or by similar steps.
The impelling means 4 are paddle-like members which engage the material and push it from the inlet end of the container toward the outlet end while simultaneously setting the material into rotary motion so that the material follows substantially a helical path along the inside of the container in moving from inlet 3 to outlet 5.
After the material in the drum moves away from the impelling means 4, glue is applied thereto by the feeding tubes or elements 9 which plow through the material and open the material up somewhat so that there is a primary distribution of glue on the material without the glue, however, uniformly wetting all of the particles or fibers of the material. Due to the action of impelling means 4, together with the action of the elements 9 in maintaining the material in motion, the material continues on into the mixing zone where the material is maintained in rotary motion by the needle-like mixing members 13 while the material continues to move toward outlet 5 due to the impelling means 4.
During the movement of the material through the mixing zone, the relative movement between the needle-like members 13 and the material, combs through the material and distributes the glue in the material so that all fibers and parts in the material become uniformly treated with the glue material.
Further, the radially outer ends of elements 13 are bent off in the planes of movement thereof so as to be concave on the leading side, as will be seen in FIG. 2, and the configuration thus imparted to the mixing elements assists in causing relative motion between the individual fibers and particles of the material and, especially, maintains the material in a live condition adjacent the circumferentially inner wall of the container where the possibility exists that a dead region could exist.
At no time after the application of glue to the material is the material subjected to the action of paddle-like impelling elements similar to those indicated by reference numeral 4 in FIG. 1. In the absence of engagement of the material by such elements after glue has been added to the material, the tendency for the material to form into balls or agglomerates is not encountered.
Rather, any tendency for the material to agglomerate is prevented by the action of the needle-like mixing members 13. The result is that the material, when discharged through outlet 5, is extremely uniformly admixed with the glue added thereto and a superior product results when the material is hot pressed to form boards and the like for construction and similar purposes.
It is, of course, to be understood that the present invention is, by no means, limited to the specific showing in the drawing but also comprises any modifications within the scope of the appended claims. | An apparatus for applying glue to the fibers of material, such as wood and the like, especially to cellulose-containing fibers, in which the fibers are supplied to one end of a substantially horizontal drum and removed from the other end thereof with the fibers being impelled through the drum by impelling elements mounted on a central shaft rotatable in the drum and at the inlet end of the drum. Glue is applied to the material downstream from the impelling elements, and downstream from the region of glue application the material is intensively combed by tapering elements mounted on the central shaft. The glue is applied by radial elements mounted on the central shaft and to which glue is supplied through the shaft. | 1 |
BACKGROUND
The present disclosure relates to concrete construction, and more particularly, but not exclusively, to a dowel bar assembly for connecting adjacent concrete slabs.
The construction of concrete surfaces is commonly accomplished by forming a plurality of adjacent concrete slabs that are separated by expansion joints. In some applications, the concrete slabs may support heavy loads, such as loads exerted by equipment on aircraft runways, taxiways, and parking aprons. The heavy loads that are supported by an individual concrete slab can cause vertical movement of the slab with respect to adjacent slabs. To prevent this damaging movement, the load may be distributed through load bearing dowels that extend between adjacent slabs across expansion joints. These dowels are typically formed from a ductile material, such as steel or fiberglass, which transmits the load and provides additional reinforcing structure. Different techniques exist for installing such dowel bars into a concrete slab.
One of the typical methods for installing dowel bars is to create a dowel bar assembly or apparatus that includes wire side rails for supporting a dowel bar in place prior to the pouring of a concrete slab. Typically, a dowel bar assembly is positioned in an area where two concrete slabs will abut one another. An expansion member may be mounted on the dowel bar assembly, and commonly delineates the respective edges of the concrete slabs. A first concrete slab is then poured along one side of the expansion member, partially covering the dowel bar assembly. A second concrete slab is subsequently poured along a second side of the expansion member, covering the other side of the dowel bar assembly. Therefore the two concrete slabs are separated by an expansion joint and connected together by the dowel bars to help distribute heavy loads across both of the concrete slabs.
Joining the wire side rails to the dowel bar is usually time consuming and costly. The wire rails are usually made of steel and susceptible to corrosion. Often, the corrosion spreads from the wire rails to the dowel bar. Previously, attempts to control the corrosion were made by coating the dowel bar with epoxy. However, commonly the side frame is welded to the epoxy coated dowel bar, and such welds enable corrosion to enter into the dowel bar even with the epoxy coating since the weld areas are not coated. Therefore, one drawback to this method of forming concrete slabs is increased corrosion. In addition, another drawback is the time consuming and costly method of constructing the dowel bar assembly. Furthermore, if the assembly is constructed at a factory, transport and storage of the devices becomes difficult and costly as well.
Therefore, many needs remain in this area of technology.
SUMMARY
In one aspect of the dowel bar assembly there is an apparatus for combining adjacent concrete slabs. The apparatus includes a dowel having an end portion for placement into a concrete slab. The apparatus also includes an end cap having an open end for receiving the dowel end portion. The end cap has a hood extending at least partially around the dowel receiving end of the end cap and positioned transverse to the longitudinal axis of the dowel. The hood defines a curved channel. The apparatus also includes a side frame having at least one wire received in the curved channel of the end cap.
Another aspect of the dowel bar assembly includes an end cap for placing on a dowel. The end cap includes a central portion defining a recess for receiving an end of the dowel, the central portion having a first end, a second open end for receiving the end of the dowel, and an outer surface. The end cap also includes a hood surrounding the defined recess and defining a curved channel around at least a portion of the outer surface of the central portion.
Yet another aspect of the dowel bar assembly includes an end cap for connecting a side frame having a first cross wire and a second cross wire to a dowel. The end cap includes a receiving portion defining an interior area for receiving an end of the dowel. The end cap also includes a supporting portion integrally formed with the receiving portion for supporting the side frame. The supporting portion also includes a first wire support for supporting the first cross wire and a second wire support for supporting the second cross wire. The first and second wire supports are arranged substantially parallel to each other.
A further aspect of the dowel bar assembly includes an end cap for connecting a dowel to a side frame. The end cap includes a tubular central portion having a first end and a second end, where at least one of the ends is an open end for receiving the dowel and the tubular central portion defines an outer peripheral surface. The end cap also includes a first sleeve coupled to the central portion and positioned along a first tangent of the outer peripheral surface of the tubular central portion for receiving a portion of the side frame. In addition, the end cap includes a second sleeve coupled to the central portion and positioned along a second tangent of the outer peripheral surface of the tubular central portion for receiving a differing portion of the side frame. The second tangent is placed on an opposite side of the outer peripheral surface of the tubular central portion from the first tangent. The end cap also includes a resilient protrusion coupled to the central portion for receiving a further differing portion of the side frame.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an exemplary dowel bar assembly that is partially embedded in abutting concrete slabs.
FIG. 2A is a perspective view of one end of the dowel bar assembly of FIG. 1 , with the side frame decoupled from the end cap of the assembly.
FIG. 2B is a perspective view of one end of the dowel bar assembly of FIG. 1 , with the side frame coupled to the end cap of the assembly.
FIG. 3A is a cross-sectional side view of the end cap of the dowel bar assembly of FIG. 1 , with the side frame partially coupled to the end cap.
FIG. 3B is a cross-sectional side view of the end cap of the dowel bar assembly of FIG. 1 , with the side frame completely coupled to the end cap.
FIG. 4 is a rear perspective view of the end cap of the dowel bar assembly of FIG. 1 .
FIG. 5 depicts a plurality of dowel bar assemblies in a stacked arrangement.
FIG. 6A is a perspective view of a first alternative aspect of a dowel bar assembly holding a side frame.
FIG. 6B is an exploded perspective view of the first alternate aspect of FIG. 6A .
FIG. 6C is a cross-sectional side view of the end cap of the dowel bar assembly of FIG. 6A , with the side frame completely coupled to the end cap.
FIG. 6D is a cross-sectional side view of a variant of the end cap of the dowel bar assembly of FIG. 6A , with the side frame completely coupled to the end cap.
FIG. 7 is a perspective view of an end cap for a second alternative aspect of a dowel bar assembly.
FIG. 8 is a perspective view of an end cap for a third alternative aspect of a dowel bar assembly.
FIG. 9A depicts a plurality of dowel bar assemblies having the end caps of FIG. 8 stacked upon each other.
FIG. 9B is a cross-sectional side view of the stacked dowel bar assemblies of FIG. 9A .
FIG. 10 is a perspective view of an end cap for a fourth alternative aspect of a dowel bar assembly.
FIG. 11 is a perspective view of an end cap for a fifth alternative aspect of a dowel bar assembly.
DETAILED DESCRIPTION
The descriptions contained here are meant to be understood in conjunction with the drawings that have been provided.
FIG. 1 illustrates an exemplary dowel bar assembly 30 . The dowel bar assembly 30 assists in preventing vertical movement of the concrete slabs 32 a , 32 b (collectively designated 32 ). The concrete slabs 32 abut each other along an expansion member 34 that is placed between the two abutting concrete slabs 32 . The expansion member 34 can be made from different materials known by those skilled in the art. For example, in some aspects the expansion member 34 is made of a rubber, cork, fiberglass or various other types of resilient materials. In other aspects, the expansion member 34 is a cardboard or similar type material, such as those used in sidewalk blocks. The expansion member 34 usually either expands or contracts to fill in the area between the abutting concrete slabs 32 during changes in temperature. Extending through the expansion member 34 and out of one of the concrete slabs 32 is at least one dowel bar 36 . In the illustrated aspect, three dowel bars 36 are illustrated projecting out of the concrete slab 32 . Those skilled in the art will readily recognize that any number of dowel bars 36 can be used as may be required to transfer loads between adjacent concrete slabs. The dowel bars 36 of the illustrated aspect are shown to be cylindrical. In other aspects, however, other shapes can be used. For example, a rod with a square cross-section or even hexagonal cross-section can be used. Similarly, a variety of materials can be used for the dowel bar 36 . The dowel bar 36 can be formed from a metal material or a fiberglass material, to name a few. In some aspects, a material having anticorrosion properties, such as a coating of epoxy, may be used to prevent corrosion of the dowel bar 36 due to moisture. FIG. 1 illustrates that the dowel bar 36 extends out of the concrete slab 32 a into the other concrete slab 32 b across expansion joint 34 . In this way, the concrete slabs 32 are coupled together and a heavy load placed on one of the concrete slabs 32 a , 32 b will be spread more uniformly across both concrete slabs 32 . Each dowel bar 36 includes an end portion 38 that is sized to receive an end cap 40 . Each end cap 40 is placed on the end portion 38 of the dowel bars 36 to provide a structure for coupling a side frame 42 to the dowel bar 36 . In the illustrated aspect, the side frame 42 is constructed of two main components. The first component is a curved connection wire 44 that connects to the end cap 40 . The other component is a cross wire assembly 46 , which combines successive ones of the curved connection wire 44 together. In the illustrated aspect, there are two cross wires 46 a and 46 b . FIG. 1 illustrates that the concrete slabs 32 cover the dowel bar assembly 30 after the concrete has been poured and therefore completely buries the dowel bar assembly 30 therein.
Referring now to FIG. 2A , the assembly of the side frame 42 into the end cap 40 is illustrated. The end cap 40 includes a channel 48 that runs below the dowel bar 36 . The channel 48 is designed to receive the cross wire assembly 46 of the side frame 42 . The arrow in FIG. 2A indicates that the channel 48 receives the cross wire assembly 46 . The end cap 40 also includes a curved channel 50 that is designed to receive the curved connection wire 44 of the side frame 42 . In the illustrated aspect, the curved channel 50 is substantially U-shaped, however, in other aspects the curved channel 50 may have other shapes. The channel 48 is positioned transverse to the longitudinal axis of the dowel bar opposite the curved channel 50 . This connection of the curved connection wire 44 and the curved channel 50 is described in more detail hereinbelow with reference to FIGS. 2B and 3B . The curved channel 50 is defined by a hood 52 formed generally around the periphery of the dowel bar 36 . The hood 52 includes a resilient protrusion 54 that is used to lockingly engage the curved connection wire 44 when it has been inserted into the curved channel 50 . This is illustrated in more detail in FIG. 3B . The side frame 42 includes a curved portion 56 that is received by the curved channel 50 and is surrounded by the hood 52 when it is inserted into the curved channel 50 . The cross wires 46 and the curved connection wire 44 are coupled together using welds 58 so that the side frame 42 is provided in a pre-assembled condition.
Referring now to FIG. 2B , the attachment of a side frame 42 to the end cap 40 is illustrated. FIG. 2B illustrates the side frame 42 in a first state 60 in phantom. In this first state 60 the upper cross wire 46 a is inside of the channel 48 . After the side frame 42 has been inserted into the channel 48 it can be rotated from the first state 60 illustrated in phantom to the second state 62 illustrated in solid. Upon rotating the side frame 42 around the pivot point created by the first channel 48 the curved portion 56 of the curved connection wire 44 is placed into the curved channel 50 and is lockingly engaged inside of the curved channel 50 . To lock the curved portion 56 , the resilient protrusion 54 first bends in an upward direction and then snap fits around the curved portion 56 of the curved connection wire 44 . This configuration allows assembly of the dowel bar 36 and the side frame 42 prior to forming the concrete. The side frame 42 provides a stand for suspending the dowel bars 36 off of the ground so that they will be placed into the interior of a concrete slab.
Referring now to FIG. 3A , a cross-sectional view of the end cap 40 illustrates the first state 60 of the side frame 42 . In this state, the channel 48 receives the cross wire 46 a and the side frame 42 is positioned at an angle to a generally vertical plane P coincident with the longitudinal axis of the channel 48 . The design of the channel 48 allows the cross wire 46 a to rotate easily within the channel 48 so that the side frame 42 can be easily connected to the end cap 40 . FIG. 3B illustrates the dowel bar assembly 30 after the side frame 42 has been moved to the second state 62 . In this state, the side frame 42 has rotated around a pivot point created by the combination of the cross wire 46 a and the channel 48 . This places the curved portion 56 of the curved connection wire 44 into the curved channel 50 by deflecting the resilient protrusion 54 upwards to allow the curved portion 56 to slide into the curved channel 50 . The resilient protrusion 54 is biased towards the interior of the end cap 40 and therefore locks down around the curved portion 56 of the curved connection wire 44 once it has been completely enclosed inside of the curved channel 50 . Again, the position of the side frame 42 is at an angle to the plane P through the channel 48 . This forms a stable base out of the side frame 42 for holding the dowel bars 36 steady while the concrete is being poured. Those skilled in the art will recognize that the side frame 42 can be positioned in a range of angles from the plane P depending on the orientation of the curved channel 50 and the end cap 40 . FIGS. 3A and 3B also illustrate that the end cap 40 has an open end 64 that is designed to receive the dowel bar 36 . In addition, FIGS. 3A and 3B illustrate that a first wall 66 and a second wall 68 define the channel 48 . Those skilled in the art will recognize that channel 48 can be formed in different manners in different aspects of the dowel bar assembly.
FIG. 4 illustrates that the end cap 40 has a central portion 70 that includes a first end 72 for covering the end portion 38 of the dowel bar 36 . The open end 64 receives the dowel bar 36 and an outer surface 74 surrounds the end portion 38 of the dowel bar 36 when inserted. The hood 52 substantially surrounds the first end 72 and defines the curved channel (not shown) generally around at least a portion of the periphery of the outer surface 74 . The open end 64 of the central portion 70 of the end cap 40 provides access to a recessed area 76 defined by the inner surface 78 of the central portion 70 . The inner surface 78 includes a plurality of ribs 80 around its periphery for facilitating a friction fit to the end portion 38 of the dowel bar 36 to snugly hold the end cap 40 in place. The ribs 80 have a first portion 81 that has a first height for engaging the outer surface of the dowel bar 36 . The ribs 80 may also have a second portion 82 that has a second height greater than the first height for engaging the end portion 38 of the dowel bar 36 to limit the insertion of dowel bar 36 into the recessed area 76 .
Referring now to FIG. 5 , a plurality of dowel bar assemblies 30 are shown stacked one upon each other. Therefore, the dowel bar assemblies 30 can be pre-assembled prior to shipment and conveniently stacked upon each other so to minimize the amount of space occupied, or assembled in one area of a construction site and stacked until needed.
Referring now to FIGS. 6A and 6B , one alternative aspect of an end cap 40 W is illustrated. In FIGS. 6A and 6B identical reference numerals are used to described similar parts with the addition of a W suffix indicating that the parts are similar but slightly different as will be readily apparent from the figures. The end cap 40 W includes a first section 83 that slides over the end portion 38 of the dowel bar 36 . The first section 83 slides into contact with a second section 84 of the end cap 40 W and locks with the second section 84 of the end cap 40 W through the use of the dual resilient protrusions 85 on opposite sides of the dowel bar 36 . The curved portion 56 W of the curved connection wire 44 W is restrained between the second section 84 and the first section 83 . The end cap 40 W, like end cap 40 , has a hood 52 W around the periphery of the outer surface of the end cap 40 W that defines a curved channel 50 W for receiving the curved portion 56 W of the curved connection wire 44 W. In addition, the end cap 40 W has a channel 48 W for receiving a cross wire 46 W. Reference to FIG. 6B illustrates that the channel 48 W is only bound by one wall 68 W instead of two walls like in the end cap 40 of FIG. 4 . FIG. 6B illustrates additional detail of the end cap 40 W. The end cap 40 W has the first section 83 that is lockingly engaged into place by the resilient protrusions 85 on either side of second section 84 . The resilient protrusions 85 may include gripping ridges 86 that grip an outer portion 88 of the first section 83 and allow the first section 83 to be positioned in a plurality of locations longitudinally along the axis of the dowel bar 36 . The inner portion 90 of the first section 83 has an interior surface 92 that defines ribs 94 . Accordingly, when the second section 84 is slid over the end portion 38 of the dowel bar 36 the second section 84 can easily slide back and forth. Then when the curved connection wire 44 W is desired to be connected to the end cap 40 W, the curved connection wire 44 W is slid over the end portion 38 of the dowel bar 36 and into the curved channel 50 W of the second section 84 . Then the first section 83 is slid over the end portion 38 of the dowel bar 36 and snapped into place using the resilient protrusions 85 . Simultaneously, the ribs 94 of the first section 83 friction fit the first section 83 to the dowel bar 36 and keeps the entire end cap 40 W and side frame 42 W in stable connection with dowel bar 36 . This design of the end cap 40 W reduces the tolerances needed in the manufacture of the side frame 42 W, lowering manufacturing costs and assisting assembly.
Referring now to FIG. 6C , a cross-sectional view of the end cap 40 W illustrates how the first section 83 contacts the second section 84 of the end cap 40 W and locks to the second section 84 through the dual resilient protrusions 85 on opposite sides of the dowel bar 36 . Resilient protrusions 85 may include a series of gripping ridges 86 that grip an outer portion of the first section 83 and allow the first section 83 to be positioned in a plurality of locations longitudinally along the axis of the dowel bar 36 . Second section 84 may compress first section 83 as first section 83 is positioned more closely to second section 84 along the axis of the dowel bar 36 , enhancing the friction fit of the first section 83 to the dowel bar 36 . Resilient protrusions 85 may also be manually disengaged from first section 83 to permit end cap 40 W to be repositioned or otherwise removed as necessary.
Referring now to FIG. 6D , a cross-sectional view of a variant of the end cap 40 W illustrates how the first section 83 may contact the second section 84 of the end cap 40 W and lock to the second section 84 without the use of resilient protrusions. A portion of the inside surface of second section 84 and a portion of the outside surface of first section 83 may be formed with complementary gripping ridges 89 that are brought into mutual engagement when the first section 83 is slid into contact with the second section 84 . Second section 84 may compress first section 83 as first section 83 is advanced toward second section 84 along the axis of the dowel bar 36 , enhancing the friction fit of the first section 83 to the dowel bar 36 . The positioning of gripping ridges 89 on complementary surfaces of the first section 83 and the second section 84 additionally shields the connection and provides an effective one-way locking mechanism.
Referring now to FIG. 7 , another alternative aspect of an end cap 40 X is illustrated. Once again, similar parts are designated with identical reference characters with the addition of the X symbol to indicate that the parts are similar to the reference characters already used with readily apparent differences. The end cap 40 X includes a central portion 96 having a first end 98 that is closed and a second end 100 that is open. The second end 100 is designed to be able to receive the end portion 38 of the dowel bar 36 . The end cap 40 X includes a first sleeve 102 for receiving a first connection wire 44 a X and a second sleeve 104 that for receiving a second connection wire 44 b X. In the illustrated aspect, the first sleeve 102 and second sleeve 104 are integrally formed with the central portion 96 of the end cap 40 X. Those skilled in the art, however, recognize that in other aspects the sleeves can be coupled to the central portion 96 in other manners. The second sleeve 104 is positioned along a tangent of the dowel bar 36 and the first sleeve 102 is positioned along an opposite tangent of the dowel bar 36 that arranges the connection wires 44 a X and 44 b X substantially parallel to one another. In addition, the central portion 96 also has a resilient protrusion 106 for coupling to the cross wire 46 X. The cross wire 46 X and the connection wires 44 a X and 44 b X are pre-welded together to form side frame 42 X so that assembly is simple. The end cap 40 X is simply placed over the end portion 38 of the dowel bar 36 and then the connection wires 44 a X and 44 b X are slid into the first and second sleeve 102 , 104 . Next, the resilient protrusion 106 is clipped around the cross wire 46 X.
Referring now to FIG. 8 , another alternative aspect of an end cap 40 Y is illustrated. Once again, similar parts are designated with identical reference characters with the addition of the Y symbol to indicate that the parts are similar to the reference characters already used with readily apparent differences. The end cap 40 Y includes a connecting portion 108 that is designed to form an interior area for receiving an end portion 38 of the dowel bar 36 . In addition, the end cap 40 Y includes a supporting portion 110 that is integrally formed with the connecting portion 108 . The supporting portion 110 supports the side frame (not shown). The supporting portion 110 has a first wire support 112 and a second wire support 114 formed therein. In the illustrated aspect, the wire supports 112 , 114 are channels formed in the supporting portion, however, in other aspects of the dowel bar assembly other structures are used. The wire supports 112 , 114 lie within the apron 116 of the end cap 40 Y. The apron 116 includes a plurality of apertures 118 designed to lighten the weight of the supporting portion 110 , to allow concrete to easily flow therethrough, and to assist with stacking the dowel bar assemblies 30 Y as illustrated in FIGS. 9A and 9B . In the illustration, the first wire support 112 includes two clamp pairs 120 arranged substantially parallel to each other that are designed to clamp around a portion of the side frame (not shown), such as a cross wire (not shown). Each clamp pair may be formed of resiliently opposed clamping members, however, other aspects may use other structure to clamp around a portion of the side frame. In addition, the second wire support 114 may also include two claim pairs 112 which are also designed to clamp around a portion of the side frame (not shown). The supporting portion 110 may also include base members 124 designed to support the entire dowel bar assembly 30 Y upon the ground surface prior to the pouring of the concrete. The end cap 40 Y eliminates the need to have connection wires (not shown) having a curved portion and simply allows the dowel bar 36 to be connected to a cross wire (not shown).
Referring now to FIG. 9A , the stackability of the dowel bar assembly 30 Y is illustrated. FIG. 9A illustrates that one supporting portion 110 rests on top of another dowel supporting portion 110 and the connecting portion 108 of one dowel bar assembly 30 Y passes through the largest one of the apertures 118 of another dowel bar assembly 30 Y.
Referring now to FIG. 9B , a cross-sectional view provides additional detail of the stacking illustrated in FIG. 9A . This view illustrates clearly that the connecting portion 108 extends through an aperture 118 and supports the apron 116 along a support surface 126 . Therefore, in some situations it is preferable to pre-assemble the dowel bar assembly 30 Y prior to shipping to the construction site. The stackability of these dowel bar assemblies 30 Y facilitates ease in transporting these dowel bar assemblies 30 Y.
Referring now to FIG. 10 , an alternative aspect of an end cap 40 Z is illustrated. As in the earlier aspects, like numerals are used to refer to like parts and similar parts are designated with a Z symbol. The end cap 40 Z includes a removable top 128 that includes guide rails 130 that help it to slidingly engage the bottom portion 132 of the connecting portion 108 Z. This design allows an end portion 38 of a dowel bar 36 to be inserted into the connecting portion 108 Z. Then the end cap 40 Z can be snugly attached to the end portion 38 of the dowel bar 36 by sliding the top portion 128 so that the guide rails 130 interact with the bottom portion 132 to snap the top portion 128 over the dowel bar 36 . Like in the aspect shown in FIG. 8 , the end cap 40 Z includes a supporting portion 110 Z that includes a first wire support 112 Z and a second wire support 114 Z arranged substantially parallel to each other. These wire supports 112 Z, 114 Z each include their own respective pars of clamps 120 Z and 122 Z. In addition, they also include the base members 124 Z and an apron 116 Z to connect all of the pieces together. Accordingly, the cross wires 46 a Z, 46 b Z are coupled to the supporting portion 110 Z and the dowel bar 36 is connected to the connecting portion 108 Z to create the assembly.
Referring now to FIG. 11 , an alternative aspect of an end cap 40 V is illustrated. As in the earlier aspects, like numerals are used to refer to like parts and similar parts are designated with a V symbol. As in FIG. 10 , this aspect has a connecting portion 108 V and a supporting portion 110 V, however, the design of the connecting portion 108 V is different. The connecting portion 108 V includes an upper half 134 and a lower half 136 for surrounding the dowel bar 36 received in the lower half 136 . In the illustrated aspect, the halves 134 , 136 are clasps, however those skilled in the art will recognize that other structures are used in other aspects of the dowel bar assembly. The upper half 134 and the lower half 136 are joined together using a living hinge 138 . A living hinge 138 is used in the illustrated aspect, however, those skilled in the art will recognize that other types of hinge mechanisms for connecting the upper half 134 to the lower half 136 can be used in other aspects. The living hinge 138 allows the first tab 140 of the upper half 134 to lockingly engage with the second tab 142 of the lower half 136 . Accordingly, the upper half 134 locks around the end portion 38 of the dowel bar 36 when the dowel bar 36 is received by the lower half 136 . Similarly, like the other aspects shown in FIGS. 8 and 10 , the supporting portion 110 V includes a first wire support 112 V and a second wire support 114 V arranged substantially parallel. In addition, the end cap 40 V also includes first clamp members 120 V and second clamp members 122 V. Also, a set of apertures 118 V and base members 124 V may be used with the apron 116 V to form the supporting member 110 V.
This has been a description of the present invention and one preferred mode of practicing the invention, however, the invention itself should only be defined by the appended claims. | An apparatus for combining adjacent concrete slabs including a dowel, an end cap, and a side frame. The end cap has a hood defining a curved channel extending at least partially around a dowel receiving end. The side frame has at least one wire received in the curved channel. Also, an end cap having an integrally formed supporting portion including first and second wire supports for supporting substantially parallel side frame cross wires. Also, an end cap including first and second sleeves positioned along opposing tangents of the outer peripheral surface of the end cap for receiving differing portions of a side frame, and further including a resilient protrusion for receiving a further differing portion of the side frame. | 4 |
BACKGROUND
[0001] Many people have suffered and continue to suffer from flesh wounds of varying degrees. Such flesh wounds include but are not limited to first and second degree burns, abrasions, cuts, etc. Such flesh wounds can have a severe impact on a victim if they alter a victim's physical appearance, especially on a long term or a permanent basis.
[0002] For example, a sizeable second degree burn on a victim's face could be expected to have both physical and emotional effects on the victim. Depending on the nature and extent of the burn, the victim's face could take on a gruesome appearance. Such an appearance could put substantial strain on human interactions, both in a social context and in a work-environment context. This strain can lead to physical, emotional and financial consequences. These consequences can further challenge the victim's self-image. Worse, after the facial wound is physically healed, using conventional techniques, the flesh may never return to a normal, pre-burned condition in color or texture. Thus, the victim could be left to cope with long term, or even permanent, damage.
[0003] Unfortunately, flesh wounds are very common, and happen to people of all ages, races, gender, and socio-economic status. For example, children are burned in house fires, and soldiers suffer from attacks on the battleground.
[0004] Flesh wounds of varying severity are not limited to humans; mammalian skin generally is subject to flesh wounds. Family pets, for example, are also burned in house fires.
[0005] Thus, methods of treating flesh wounds are needed. A method of treatment that is capable of restoring wounded flesh to substantially a pre-wound condition is desired. A method of treatment that is inexpensive is desired. A method of treatment that is non-invasive is desired.
[0006] Similarly, methods of preparing a composition to treat flesh wounds are needed. A simple method of preparing a composition is desired. A method of preparing a composition that is relatively fast—within a few hours—is desired. A method of preparing a composition that is inexpensive is desired.
SUMMARY
[0007] A method of treating a flesh wound is provided that has at least one of the desired traits of such methods. Similarly, a method of preparing a composition to treat flesh wounds is provided that has at least one of the desired traits of such methods.
[0008] A method of repairing a flesh wound to, substantially, a pre-wound condition is provided herein. The method comprises the steps of providing a composition prepared by a certain process and applying an amount of the composition to the wound sufficient to substantially cover the wound, wherein said application occurs about twice daily for a period of at least about ten days. The process of preparing the composition involves: (i) providing an ingredient consisting essentially of eggs; (ii) mixing the eggs until they form a substantially uniform mixture; (iii) adding the mixture to a cooking vessel; (iv) heating the cooking vessel until the mixture comprises a black liquid component; (v) agitating the mixture during heating; (vi) collecting the black liquid component; and (vii) cooling the black liquid component.
[0009] A method of preparing a composition to treat flesh wounds is prepared herein, as is the composition prepared by the method. The method of preparing a composition for treatment of a flesh wound includes the step of providing an ingredient consisting essentially of raw eggs. In one embodiment, no other ingredients are added to the eggs, whether natural or synthetic. In another embodiment, de minimus amounts of other ingredients, especially natural ingredients, are added. The method also includes the steps of mixing the eggs to form a mixture, then adding the mixture to a cooking vessel and heating the cooking vessel until the mixture comprises a black liquid component. The mixture can be agitated during heating. The black liquid component can be collected, then cooled and applied to a flesh wound.
DETAILED DESCRIPTION
[0010] Surprisingly, it has been discovered that an all natural composition, prepared according to the methods disclosed herein and applied to flesh wounds according to the application methods disclosed herein, can repair flesh in a flesh wound to, substantially, a pre-wound condition.
[0011] Wounded flesh is “substantially” returned to a pre-wound condition if appears generally as it did in a pre-wound condition, as determined by visual inspection. A visual inspection can involve a naked eye comparison of wounded flesh that has been repaired using the methods disclosed herein with unwounded flesh, from a distance of at least about three feet in normal indoor lighting conditions. Normal indoor light conditions means, generally, subject to some natural and artificial light, but not necessarily subject to harsh lighting such as that often associated with fluorescent lights.
[0012] Repaired flesh passes a visual inspection even if the repaired flesh has minor inconsistencies in color and texture when compared to unwounded flesh. Inconsistencies in color and texture are minor if those inconsistencies are not observable by a visual inspection from a distance of at least about 15 feet in normal indoor lighting conditions.
[0013] An alternative method for determining if color of repaired flesh is substantially returned to a pre-wound condition is to compare a healed wound flesh sample with unwounded flesh using instrumentation such as a tri-stimulus colorimeter such as a Minolta ChromaMeter. Using such instrumentation, color is expressed as numerical coordinates, L*, a* and b*. The L* value expresses luminescence, reporting the relative brightness of the flesh. The a* value represents the balance between green and red. The b* value represents the balance between blue and yellow. If the a* value, the b* value and the L* value of the healed wound flesh color each differ no more than 15%, no more than 10%, or no more than 5% from the corresponding coordinate of the unwounded flesh, the wounded flesh is repaired, substantially, to a pre-wound condition.
[0014] An alternative method for determining if color of repaired flesh is substantially returned to a pre-wound condition is to compare a healed wound flesh sample with unwounded flesh using spectophotometry. Spectophotometry involves instrumentation that produces spectra showing wavelength regions where certain flesh colors are reflected. If the spectra of the healed wound flesh sample produces spectra that are substantially similar (peaks and valleys occurring generally within the same wavelength regions) to that of unwounded flesh, the wounded flesh is repaired, substantially, to a pre-wound condition.
Preparing the Composition
[0015] Many embodiments of methods of preparing the composition that is used to repair flesh wounds are disclosed herein. In one embodiment, an all natural composition is prepared by cracking open one or more eggs, and placing resulting egg yolks and egg whites into a cooking vessel. Chicken eggs can be used, as can other types of eggs. Egg shells can be discarded. The cooking vessel may be any type of container capable of enduring heat. Non-limiting examples of suitable cooking vessels include covered and uncovered pots and pans.
[0016] The egg yolks and whites, together, may be subjected to agitation before, during and following heating of the cooking vessel. Agitation of any form can be used. Non-limiting examples of agitation include mixing and stirring. Heating may be accomplished using any suitable heating source or method. In one embodiment, a heating source comprises the application of low or medium or high heat supplied by a gas or electric range to the cooking vessel. In another embodiment, an oven is used as a heating source. In still another embodiment, an open fire is used to heat the cooking vessel. Generally, the higher the temperature applied to the cooking vessel, the faster the composition will be prepared.
[0017] After about 20 to 65 minutes (or after about 30 to 55 minutes) of heating in a covered vessel at a high temperature (as a non-limiting example, 450° F.-500° F.), the heated egg mixture can take on a brown color. Agitation and heating can continue until the egg mixture turns black, and generates a black liquid component. Any remaining solid egg substance in the cooking vessel may be discarded.
[0018] The black liquid component can be cooled using any known method. It can be allowed to set at about room temperature until it reaches room temperature. Alternatively, any form of refrigeration can be used to accelerate cooling to about room temperature. Cooling methods can be used that bring the black liquid component below room temperature, also. After the black liquid component is cooled, the cooled black liquid component is ready for use or storage.
Optional Ingredients
[0019] In one embodiment, no additional ingredients are added to the composition, during or after the preparation of same. In another embodiment, the composition is substantially free of added ingredients, whether natural or synthetic. Substantially free means no more than about 1% by weight of any ingredient is added, where the weight of the entire composition is the 100% reference point. Without being bound by theory, it is believed that the nature of the composition is such that no preservatives are necessary.
[0020] Surprisingly, the composition has a shelf life of at least about five to seven years, without the addition of natural or synthetic preservatives. The composition need not be stored in reduced temperatures to maintain shelf life. Ideally, the composition is stored in a re-sealable container at temperatures ranging from about 10° C. to about 40° C., or alternatively from about 15° C. to about 25° C.
[0021] In another embodiment, additional natural ingredients (including but not limited to water or natural preservatives) are added in a de minimus amount to the composition (during or after preparation of same) such that the natural ingredients do not materially affect the basic and novel characteristics of the invention(s) of the appended claims. In one embodiment, the additional natural ingredients comprise, in total, no more than about 2.5% by weight of the entire weight of the composition. In another embodiment, the additional natural ingredients comprise, in total, no more than about 1.5% by weight of the weight of the composition. Suitable additional natural ingredients do not inflame or otherwise harm or aggravate flesh wounds.
[0022] Natural preservatives include but are not limited to oils and other extracts of Anise, Birch, Cajeput, Chinese anise, Chinese Cinnamon, Cinnamon, Clove, Cumin, Eucalyptus Fir, Pine, Garlic, Heliotrope, Juniper, Lavender, Lemon, Lemongrass, Meadowsweet, Melissa Balm, Neroli, Origanum, Orris, Parsley, Peppermint, Rose, Rose Geranium, Rosemary, Sassafras, Sweet Fennel, Sweet Orange, Thyme, Violet, Wild Thyme and Ylang Ylang and the like. Other natural ingredients could be added in de minimus amounts for aroma or rheology or stability or texture purposes, so long as said natural ingredients do not change the character or effectiveness of the composition.
[0023] In another embodiment, additional synthetic ingredients (including but limited to preservatives and fragrances and surfactants) are added in a de minimus amount to the composition (during or after preparation of same) such that the synthetic ingredients do not materially affect the basic and novel characteristics of the invention(s) of the appended claims. In one embodiment, the additional synthetic ingredients comprise, in total, no more than about 2.5% by weight of the weight of composition. In another embodiment, the additional synthetic ingredients comprise, in total, no more than about 1.5% by weight of the weight of the composition. Suitable additional synthetic ingredients do not inflame or otherwise harm or aggravate flesh wounds.
[0024] In another embodiment, additional synthetic and natural ingredients are added in a de minimus amount to the composition (during or after preparation of same) such that the ingredients do not materially affect the basic and novel characteristics of the invention(s) of the appended claims. In one embodiment, the total of the additional ingredients comprise, in total, no more than about 2.5% by weight of the weight of the composition. In another embodiment, the additional ingredients comprise, in total, no more than about 1.5% by weight of the composition. Suitable additional ingredients do not inflame or otherwise harm or aggravate flesh wounds.
[0000]
TABLE 1
Provides a Guideline for Preparing the Composition
Step
Instruction
1
Crack eggs and pour contents into a cooking vessel and mix
2
Heat the cooking vessel for about 30 minutes, stirring
eggs periodically
3
When eggs turn black and take on the consistency of a liquid,
remove liquid component from heat
4
Allow black liquid component to cool
[0025] The guideline in Table 1 is not intended to limit the scope of the appended claims, but merely to teach one method of preparing a composition used to repair flesh wounds.
Applying the Composition to Flesh Wounds
[0026] The composition prepared by the methods described can be applied to a flesh wound such as first and second degree burns, abrasions, cuts, etc.
Initiating Treatment
[0027] Generally, it has been found that wounded flesh is more likely to be repairable to a substantially pre-wound condition if treatment begins shortly after an onset of a flesh wound. In one embodiment, a first application of the composition to the wound occurs within one day of the onset of the wound. In another embodiment, a first application of the composition to the wound occurs within two days of the onset. In another embodiment, a first application of the composition to the wound within a week of the onset.
Application Methodology
[0028] Applying the composition to the flesh wound can occur in many ways. For each application, an amount of the composition is selected so that the composition can substantially cover the wounded flesh. The application may be done by hand or with an applicator of any kind. Non-limiting example of applicators include a brush or cotton swab or a dry or moistened towelette.
Application Frequency
[0029] In one embodiment, the composition is applied to the wound at least once per day. The composition may also be applied to the wound at least twice daily, or at least about three times daily. More applications may be suitable.
Application Duration
[0030] In one embodiment, treatment with the composition lasts for at least about seven days. Treatment period may vary, depending upon the nature and extent of the flesh wound. Treatment may occur over a period of at least about ten days, at least about fourteen days, or at least about twenty-one days, depending upon the circumstances. About half-way through the treatment period, harmed skin may peel off, and the appearance of regenerated skin may become apparent. At this point, the wound may still have areas discolored to a reddish hue. Applications of the composition can continue until the skin is back, substantially, to its pre-wound color.
[0031] Without being bound by theory, it is believed that the nature of the composition is such that no antibiotics are necessary for use with the composition.
[0000]
TABLE 2
Provides A Guideline For Application of the Composition
Step
Instruction
1
Identify a recently incurred flesh wound
2
Apply an amount of the composition to the wounded flesh
twice daily using a small brush
3
If a portion of the wounded flesh dries out, re-apply the
composition to at least the dried portion
to keep the wounded flesh moisturized
4
Repeat applications of the composition during the period when
wounded flesh peels or falls off and a new
layer of skin appears
5
Continue applications of the composition to otherwise healed
skin that remains red
6
After a period of applications lasting for about three weeks, the
skin is substantially repaired to its pre-wound condition
[0032] The guideline in Table 2 is not intended to limit the scope of the appended claims, but merely to teach one method of applying the composition to repair flesh wounds.
[0033] Those skilled in the art will recognize that the present invention is capable of many modifications and variations without departing from the scope thereof. Accordingly, the detailed description and examples set forth above are meant to be illustrative only and are not intended to limit, in any manner, the scope of the invention as set forth in the appended claims. | A method of repairing a flesh wound to, substantially, a pre-wound condition is provided. The method includes the steps of providing a composition prepared by a certain process and applying an amount of the composition to the wound sufficient to substantially cover the wound, wherein said application occurs about twice daily for a period of at least about ten days. The process for preparing the composition includes the steps of providing an ingredient consisting essentially of eggs; mixing the eggs until they form a substantially uniform mixture; adding the mixture to a cooking vessel; heating the cooking vessel until the mixture comprises a black liquid component; agitating the mixture during heating; collecting the black liquid component; and cooling the black liquid component. A method of treating a flesh wound is also provided, as well as a method of preparing a composition for treatment of a flesh wound. | 0 |
This was made with Government support under DAAL 03-86-C-0022 awarded by U.S. Army Research Office. The government has certain rights in this invention.
This application is a division of application Ser. No. 07/370,667, filed Jul. 23, 1989, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a vibration detector for a rotating shaft, and more particularly, to such a detector used with a Czochralski-type crystal puller.
In the Czochralski-type crystal puller, a melt of the crystal material is disposed in a heated crucible, which is attached to a rotating shaft. Surrounding the heater is an insulating jacket called "heater furniture", and the whole apparatus is mounted on a baseplate. A seed crystal is placed in the melt and pulled up, and some of the melt solidifies on the seed in crystallographic alignment therewith. This solidified portion is called the "boule". When the crystal to be formed is GaAs, a very high pressure inert gas must be used to prevent the As from vaporizing. The high pressure causes the gas to be a good thermal conductor. To prevent loss of heat through the gas, which would occur if the gas goes between the heater furniture and the crucible, tight tolerances are used between the rotating crucible and the heater furniture, in particular an insulating cap thereof. However, then the crucible will sometimes make contact with the cap. If the contact is hard enough, it will cause the crucible to break out into a rotary oscillation. This oscillation can cause failure to gain control of crystal growth, and therefore termination of the pull with shorter than desired crystal length, twinning or dislocations in the crystal before the desired length is achieved, and breaking of the boule off the seed and its falling into melt. If boule breakage occurs, it can fracture the crucible. This often causes catastrophic damage to the puller, and since the leaking melt is conductive and hot, this can result in a destroyed heater and even a partially melted baseplate. Further, all items that come in contact with the melt (except the crucible) become contaminated waste.
Presently it can only be determined if the crucible is in a rotational oscillation by observing it on a video monitor. This is dependent on sufficient heat in the crystal chamber to adequately light the crucible, e.g., at least about 4 hours after start of heat-up. It is also necessary to have an operator present at the time of the oscillation and act promptly (typically within a few seconds) to correct it.
It is therefore an object of the present invention to have a warning system for vibration of rotating shaft that provides clear and early warning of the vibration.
SUMMARY OF THE INVENTION
Apparatus in accordance with the invention for detecting vibration of a shaft comprises at least a first non-contacting proximity sensor adapted to be disposed proximate the shaft; filtering means coupled to said sensor; and AC detection means coupled to said filtering means.
A method in accordance with the invention for detecting vibration of a shaft comprises sensing vibration in the shaft without contacting the shaft to provide a sensor signal; filtering said sensor signal; and AC detecting the filtered signal.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a partly cross-sectional and partly block diagram of the apparatus in accordance with the invention;
FIG. 2 shows a detail of a block used in FIG. 1; and
FIG. 3 shows a strip recorder output graph.
DETAILED DESCRIPTION
As shown in FIG. 1 a crucible puller apparatus, generally designated 10, is largely conventional and can be Model 358 made by Cambridge Instruments, Cambridge, U.K., and thus will be only briefly described. A cylindrical sidewall 11 overlies a base plate 12 to form with a top (not shown) a pressure chamber. Plate 12 has a drive shaft 14 extending therethrough that is driven at its bottom end by drive apparatus 16. Apparatus 16 comprises both a motor (not shown) for rotation of shaft 14 and another motor and worm gear (neither shown) for vertical linear motion of shaft 14. Coupled to the upper end of shaft 14 is crucible support rod hardware 18, which in turn supports a graphite crucible holder 20. Disposed within holder 20 is a BNO 3 crucible 22 of between about 0.015 to 0.020 inches (0.0381 to 0.0508 cm) thickness. Disposed around crucible holder 20 is an electrical resistance heater 24, while disposed around heater 24 is heater furniture 26 comprising alternating layers of graphite and graphite blankets. An insulating furniture cap 28 overlies heater furniture 26 and is considered a portion thereof. The clearance gap 90 between cap 28 and holder 20 is very small to prevent an inert gas (not shown), e.g., Ar, N 2 , etc., at very high pressure from flowing therebetween and causing loss of heat. This inert gas is used at a high pressure to prevent vaporization of product reagents, e.g., Ga, As, etc. Within crucible 20 is a melt 30 of a semiconductor material, e.g., GaAs, while above melt 30 is a protective layer 32 of, e.g., B 2 O, to prevent contamination of melt 30 by any O 2 that may be present in the chamber. A seed crystal 34 of the product to be grown, e.g., GaAs, has grown from it a boule crystal 36.
In operation, the seed crystal 34 is rotated and simultaneously pulled up by apparatus (not shown) as the boule crystal 36 grows, which tends to lower the top level of melt 30. Simultaneously, apparatus 16 rotates drive shaft 14 in the opposite direction from that of crystals 34 and 36 and moves it up. This upward movement is to keep the top level of melt 30 at a constant level relative to heater 24, which has been found to be critical for good monocrystalline growth. However, due to the very small gap 90 between cap 28 and holder 20, binding can occur therebetween and hence eventually oscillation of drive shaft 14, with the negative results described above, e.g., damage to the crucible, the crystal, and the puller.
In accordance with the invention, two non-contacting proximity transducer probes 40 and 42 are located around drive shaft 14 just below base plate 12. Sensors or probes 40 and 42 can be of the eddy current type, i.e., coils, such as the 7200 series made by Bentley-Nevada Corp., Minden, Nev., or model KD 2400 made by Kaman Instrumentation Corp., Colorado Springs, Colo. Other types of non-contacting sensors, e.g., hysteresis, capacitance, photoranging, etc., can be used. In general, non-contacting sensors are used to limit motion pick up to that of shaft 14, and their output signals require less filtering and signal analysis to determine shaft abnormalities. Non-contacting sensors provide a DC output signal with a nominal AC component when shaft 14 is just rotating, and an additional AC signal when shaft 14 is also vibrating. The output signals from sensors 40 and 42 are applied to a signal conditioner 43 (described below).
As shown in FIG. 2, transducer sensors 40 and 42 are preferably disposed at a 90 degree angle with respect to one another. If there is binding between cap 28 and holder 20, there will be no change in the output signal from that transducer sensor which is at an angle of about 0 or 180 degrees from the binding point. Thus the 90 degree arrangement ensures an output signal from at least one transducer sensor. If desired, three or more transducer sensors at mutually equal angles can be used, or a single transducer sensor can be used to pick up vibrations, but it will not reliably pick up touching.
The analog signals from transducer sensors 40 and 42 are respectively applied to transducers 40a and 42a and then passed through one Hz high-pass cut off frequency filters 44 and 46, respectively, and are summed together in adder 48. In a particular embodiment, each of the filters 44 and 46 comprises a series input capacitor and the shunt input resistance of adder 48, and an additional two pole high pass filter with a 1 Hz cut off frequency in adder 48 for a total of three poles of high pass filtering. The filters 44 and 46 are used to eliminate the 0 to 30 RPM (DC to 0.5 Hz) normal noise of rotating drive shaft 14. The resulting signal from adder 48 is passed through a low-pass filter 50 of approximately 500 Hz cutoff to eliminate shaft pressure seal noise at a frequency of about 1.2 KHz caused by sequential stick and slip. In a particular embodiment, filter 50 comprises a 6 pole active modified Bessel filter for good pulse response. Details of designing such a filter can be found in "Transducer Interfacing Handbook" by Analog Devices Co., Norwood, Mass. This high frequency stick and slip does not cause the damage that the above described binding does because its frequency is well above the resonant frequency of the entire pulling apparatus. Further, a narrower pass band has been found sometimes useful, e.g., 70 to 200 Hz, and more particularly, 100 to 130 Hz. The lower of these frequencies can be used in the filters 44 and 46, while the higher of these frequencies can be used in filter 50. It will be appreciated that filters 44 and 50, and also 46 and 50, comprise a band pass filtering means. If desired, the output signals from transducers 40a and 42a can be directly added and the added signal passed through a band pass filter with the lower and upper cut off frequencies given above.
The output signal from filter 50 is then full wave rectified by AC detector or rectifier 52. A full wave rectifier is preferably used so that motion of shaft 14 in either direction can be detected although other types of rectifiers can be used. In a particular embodiment, rectifier 52 was an active rectifier. The output signal from rectifier 52 is a D.C. representation of crucible behavior and is applied to a peak detector 54 and from it to a chart recorder (not shown) for display. In a particular embodiment, wherein the chart recorder had a bandwith of 3 Hz, peak detector 54 had a time constant of 10 seconds. However, if the chart recorder has a wider bandwidth, then a lower time constant can be used. Further, peak detector 54 was of the active type.
The output signal from rectifier 52 is also applied to an alarm circuit 56. Low level D.C. (approximately 50 mv) from rectifier 52 represents normal crucible activity. Rapid increases in D.C. level are indications of abnormal crucible behavior. In the alarm circuit 56, if the full wave rectified D.C. voltage exceeds a preset trip point value determined by a potentiometer 58, a retriggerable monostabile multivibrator on-shot therein (not shown), turns on a resettable audible alarm 60 and light 62. If the fault was caused by a momentary contact, the alarm will sound for approximately one second, but the light will stay on until the operator resets it. In the event of a crucible oscillation, the alarm 60 and light indicator 62 will remain on until the fault, i.e., oscillation, is cleared and/or a reset switch (not shown) in alarm 56 has been pressed.
FIG. 3 shows a chart recorder output calibrated in 24 hour time. Up to about 0930 there is no binding. This is due to an initial alignment that is performed before the puller starts operation. After 0930 some binding takes place as indicated by spikes 70. As time passes, the spikes become larger with a particularly large spike 72 at 1300, thus indicating that the binding is becoming harder. After 1330, several large spikes 74 occur with a generally increasing amplitude. Finally, at about 1415, a very large continuous oscillation 76 occurs. An operator observing the oscillation 76 can clear the incipient fault by slowing down the rotation of shaft 14 and then bring it back up to normal rotational speed to resume the normal growth rate of boule 36. Usually when bringing shaft 14 back up to normal speed, the oscillation will not reoccur because the binding caused by grinding of cap 28 and/or holder 20 increases the tolerance therebetween.
It will be appreciated the many other embodiments are possible within the spirit and scope of the invention. For example, an AC detector, such as an AC voltmeter, can be coupled to the output of filter 50, or even directly to the output of adder 48, and the needle or digits of the voltmeter watched by the operator for a rising average value. This eliminates the need for elements 50 to 62 of FIG. 2. | Apparatus for detecting abnormal vibration in a shaft, such as a rotating crucible holder drive shaft of a crystal puller, has a pair of sensors disposed 90 degrees with respect to each other. The signals are high pass filtered and added together, then low pass filtered and full wave rectified to operate an alarm and strip recorder. A method for detecting vibration in a shaft comprises sensing vibrations in the shaft, filtering the sensed signals, and rectifying the filtered signals. | 8 |
BACKGROUND
1. Field of the Invention
The inventions relates to the field of digital transactions, and more particularly to digital signatures for certifying electronic data.
2. Art Background
General Theory
In a typical digital message transaction, a first party (the sender) wants to send a digital message to a second party (the receiver) using a digital transmission medium (such as the Internet). The sender wants to ensure that a third party (the intermediary) cannot modify the message in any way. Specifically, the sender wants to ensure that the intermediate cannot intercept and read or modify the digital message.
In the following discussion, plaintext, that is, an un-encrypted message, is denoted by the symbol P. Plaintext can be a stream of bits, a text file, a stream of digitized voice, or a digital video image, to present just a few of the many possibilities. From the perspective of a digital computer, P is simply binary data.
Ciphertext, that is, encrypted data, is denoted by C. Like plaintext, ciphertext is also binary data. The encryption function E operates on P to produce C. Or, in mathematical notation:
E(P)=C
In the reverse process, the decryption function D operates on C to produce P:
D(C)=P
Since the whole point of encrypting and then decrypting a message is to recover the original plaintext, the following identity must hold true:
D(E(P))=P
A cipher is the mathematical function used for encryption and decryption of plaintext. To encrypt a plaintext message, the sender applies an encryption algorithm to the plaintext, producing ciphertext. The ciphertext is then transmitted to the receiver. A prying intermediary cannot read the ciphertext, because it is encrypted. To read a ciphertext message, the intended receiver applies a decryption algorithm to the ciphertext, resulting in plaintext which is readable.
Modern encryption algorithms use a key, denoted by k. The key is typically a number, and can take on many values, although the most effective keys are large numbers. The range of possible values of the key is called the keyspace. The value of the key affects the encryption and decryption functions, so the encryption and decryption functions now become a function of the key:
E.sub.k (P)=C
D.sub.k (C)=P
If the encryption key and the decryption key are the same, then:
D.sub.k (E.sub.k (P))=P
Some algorithms use an encryption key and a decryption key which are not identical. That is, the encryption key, k 1 , differs from the corresponding decryption key, k 2 . In this case:
E.sub.k.sbsb.1 (P)=C
D.sub.k.sbsb.2 (C)=P
D.sub.k.sbsb.2 (E.sub.k.sbsb.1 (P))=P
When the encryption key k1 is identical to the decryption key k2, and vice-versa, the encryption/decryption algorithms are said to be symmetric. Symmetric algorithms require the sender and receiver to agree on the key before passing messages back and forth. This key must be kept secret. The security of a symmetric algorithm rests in the key; anyone who obtains the key may decrypt and read, or decrypt, modify, and re-encrypt, messages from the sender to the receiver. Encryption and decryption using a symmetrical algorithm is denoted by:
E.sub.k.sbsb.1 (P)=C
D.sub.k2 (C)=P
Symmetric algorithms are further divided into two categories. Algorithms which operate on the plaintext a single bit at a time are called stream algorithms. Those that operate on the plaintext in groups of bits, called blocks, are called block algorithms. Block algorithms implemented on computers typically use blocks which are 64 bits in size. In both block and stream symmetrical algorithms, the same key is used for both encryption and decryption.
Public-key algorithms are designed so that the key used for encryption is different from the key used for decryption. That is, public-key algorithms are not symmetric. In public-key algorithms, the decryption key cannot be readily calculated from the encryption key. The encryption key can be made public: a complete stranger can use the encryption key to encrypt a message, but only someone with the corresponding decryption key can decrypt the message. In these systems, the encryption key is often called the public key, and the decryption key is often called the private key.
Public-key encryption, using public key k1, is denoted by:
E.sub.k1 (P)=C
Although the public key and private key are different, decryption with the corresponding private key is denoted by:
D.sub.k2 (C)=P
Sometimes, messages will be encrypted with the private key and decrypted with the public key. Such a scheme is used with digital signatures, and the same mathematical symbolism is used whether the public key is used for encryption or decryption.
E.sub.k1 (P)=C
D.sub.k2 (C)=P
Digital Signatures
Signatures are useful for certifying digital messages. A digital message, either plaintext or ciphertext, is made up of a number of bits of information. A digital signature which uniquely identifies a digital message is generated in the following manner. First, a unique identifier for the digital message is generated by means of a one-way hash function. This identifier typically comprises a sequence of bits which in many cases is 512 bits long. Using a public key algorithm, this identification is then encrypted using the private key of the owner of the digital document, who is also known as the signer. The use of a one-way hash function to generate the identification ensures that false information cannot be substituted for the original data in the digital message. The subsequent encryption of the identification generated by the hash function ensures that the signature cannot be forged. Once the signature has been generated, the message and signature are sent to the receiving party. To verify that the message was not altered during transmission, the recipient of the signed message again applies the one-way hash function to the message and then compares the resulting identification with the one obtained by deciphering the signature using the public key of the signer. If the message has been altered, then the identification which results from the receiver applying the one-way hash function to the document will be different then the one obtained by deciphering the signature using the public key.
FIG. 1A shows a prior art computer system for certifying a digital data block. A machine readable medium 130 such as a RAM or hard disk stores character data display logic 135. This character data display logic 135 is used to display character data 149 which is stored in a data block 147. The medium 130 further stores certification logic 145 for generating and verifying a digital signature for the character data 149. The character data display logic 135 is accessed by the processor 120 over bus element 140. When executed on the processor 120 upon the character data 149, the character data display logic 135 generates a visual display 105 of the character data 149 on a display area 104 of the computer monitor 100. In this example, the character data when displayed spells out the words "hello world" 105. The computer system may also comprise a keyboard 150 coupled to the bus 140 so that a human user can type in their own character data 149 for certification.
FIG. 1B shows the same computer system after a first digital signature is generated for the data block 147. Data block 147 now contains the character data 149 and a first signature block 169. The character display logic 135 does not recognize the digital signature 169 because the digital signature 169 is not in the character data format, it is not purely character data. Rather, it is comprised of a sequence of bits which do not necessarily represent human readable alpha-numeric characters. As a consequence, the computer display area 104 now shows the character data 105 and also a sequence of non-alphanumeric characters 107 representing the character data display logic 135 attempt at displaying the digital signature 169 in character format. The representation 107 of the digital signature 169 is highly distracting to a human reader and is generally meaningless.
FIG. 1C shows the computer system of FIG. 1B after a second digital signature 170 is generated for the data block 147. The second digital signature 170 certifies not only the character data 149, but also the first signature block 169. Character data display logic 135 attempts to display the character data 149 along with the first signature 169 and second signature 170. But for the reasons described above, both the first and second signatures 169, 170 cannot be rendered by the character data display logic 135 in a manner which is meaningful to the human user. Rather, the two signatures 169, 170 are displayed as binary "garbage" 107 on the computer display.
Improvements Needed
It would be desirable to eliminate the unpleasant visual effects associated with displaying signatures appended to digital messages, using standard facilities of modern computer operating systems. These standard facilities include methods by which a signature can identify the logic to use for rendering the signature on a display device. It would also be desirable if a digital signature was not restricted to certifying all of the data in a disk file, but instead could be used to certify only the message data, a prior signature, or any combination of the message data and any number of prior signatures. One disadvantage of the prior art certification scheme depicted in FIGS. 1A-1C is that it certifies all of the data in a data block including any prior signatures which are contained along with message data. Human transaction models require more flexibility than this scheme permits. For example, a message which must be read and approved by three persons may require a more flexible transaction model. The first person reads the message and applies his digital signature, indicating he has read and approved the contents of the message. The second person reads the message and applies his signature to it. However, the data block now consists of both the message data and the first party's signature. By certifying the entire data block, instead of only the original message data, the second party certifies that he has read and approved of the message data and further certifies that the first party did also. In other words, the second party certifies both the message and the first party's signature. Likewise, when the third party reads the message and then certifies the file, he certifies not only the message data but also the first and second party's signatures.
Another real world example in which greater transaction flexibility is required is with passports and visas. Countries attach visa certificates to the passports of parties who enter the country. If the person has visited other countries prior to the current one he is entering, then the passport may have previous visas attached. When an entry visa is applied to a passport, it certifies only the passport for that particular country; it does not certify the visas of countries which may have been previously applied. A more flexible transaction model would help enable digital processing of visas and passports.
SUMMARY OF THE INVENTION
The invention is a machine-readable medium storing at least one non-certificate data block, at least one prior certificate, a new certificate which certifies a combination of less than all of a union of the at least one non-certificate data block and the at least one prior certificate, a mechanism which allows users to directly manipulate an control all the aforementioned components through a graphical user interface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A. shows a prior-art computer system for certifying digital data block
FIG. 1B. shows the computer system of FIG. 1A after a first digital signature is generated for the data block.
FIG. 1C. shows the computer system of FIG. 1B after a second digital signature is generated for the data block
FIG. 2A. illustrates a computer system for certifying a data block.
FIG. 2B. shows the computer system of FIG. 2A, in which a second certificate has been added to the data block
DETAILED DESCRIPTION
In the following description, numerous specific details are set forth such as system diagrams, flow diagrams, etc, in order to provide a thorough understanding of the present invention. In other instances, well-known structures and techniques have not been shown in detail because to do so could unnecessarily obscure the present invention. The specific arrangements and methods described herein are merely illustrative of the principles of the present invention. Numerous modifications in form and detail may be made by those of ordinary skill in the art without departing from the scope of the present invention. For example, although later certificates (later in time) are shown in the figures as being embedded to the end of the data to certify, one skilled in the art will readily appreciate that the certificates may be embedded at any location within the data.
FIG. 2A shows a computer system for certifying a data block 247. The system includes a machine-readable medium 230 for storing program logic and data. The medium 230 contains a data block 247, and this data block contains a (non-certificate) character data block 249 and also a first certificate 253. The first certificate 253 comprises a first signature 269 and also a first dynamic link block 265 which is described in detail below. The medium 230 also includes a certification logic block 245, a signature display logic block 237, and a character display logic block 235. The certification logic block 245 contains logic which, when executed on processor 220, generates the first signature 269 for character data block 249. The signature display logic block 237 contains logic for displaying the first signature 269 on the computer display 204 within the computer monitor 200, in a manner which is meaningful to a human user. Likewise, the character display logic block 235 contains logic for displaying the character data 249 on the computer display 204. Each of the blocks stored on medium 230 is accessible by computer processor 220 over bus element 240. A keyboard 250 is available to allow a human user to enter the character data block 249.
Within the first certificate 253, the first dynamic link block 265 contains an identification ID3 of the character data block 249 which the first signature 269 verifies. The first dynamic link block 265 also contains an identification ID1 of the certification logic block 245 for verifying that the first signature 269 accurately verifies the character data block 249. The first dynamic link block 265 also contains an identification ID2 of the signature display logic block 237. In this case the character data block 249, once displayed, comprises the words "hello world" 205. The first signature block 269, once displayed by signature display logic 237 executing on processor 220, comprises a bitmapped signature image 207. The first signature block 269 is displayed in human-readable form because the signature display logic 237 understands the digital format of the first signature block 269 and is able to display it in a meaningful way to humans. The character data display logic 235 typically inputs the entire data block 247 including the character data 249 and first certificate 253. The character data display logic 235 displays the character data block 249 of the data block 247. The identification ID2 of the signature display logic 237, the identification ID1 of the certification logic block 245, and the identification ID3 of the character data block comprised by the first dynamic link block 265 are implemented using standard facilities of the operating system which controls the computer system in FIG. 2A. Because the character data display logic 235 recognizes the identification ID2 in the first dynamic link block 265 and invokes the signature display logic 237 to display the first signature block 269, instead of attempting to display the first signature block 269 as character data. An example of a standard operating system facility for making the identifications ID1, ID2, and ID3 is the Object Linking and Embedding (OLE) standard for the Windows™ operating system.
The character data display logic 235 uses the identification ID1 of the certification logic block 245 for confirming that the first signature 269 accurately verifies the (non-certificate) character data block 249. The human user can cause the character data display logic 235 to do this by selecting the bitmapped signature image 207 using either the keyboard 250 or the mouse 222. When the bitmapped signature image 207 is selected, character data display logic 235 invokes the certification logic 245 on the first signature block 269 and character data block 249. The certification logic 245 then generates a signature using a hash function, decrypts the first signature block 269 using a public key, and compares the newly generated signature with the decrypted signature. If the signatures match, then first signature block 269 is verified.
In FIG. 2B, a second certificate 255 is added to the data block 247. The second certificate 255 comprises a second dynamic link block 267 and a second signature block 271. The second dynamic link block 267 comprises an identification ID4 of the data which the second certificate block 255 certifies; in this example the identification ID4 may indicate the (non-certificate) character data block 249, the first certificate 253, or a combination of both. The second dynamic link block 267 also contains an identification ID1 of the certification logic block 245 and identification ID2 of the signature display logic 237. Assuming for the purpose of this example that the second signature block 271 verifies only the first certificate 253, then the character data display logic 235 uses the identification ID1 of the certification logic block 245 for verifying that the second signature 269 accurately verifies the first certificate 253. The human user can cause the character data display logic 235 to do this by selecting the second bitmapped signature image 209 using either the keyboard 250 or the mouse 222.
The character data display logic 235, the signature display logic 237, and the certification logic block 245 are typically comprised of sequences of computer instructions in an executable format familiar to the processor. The identification ID1 of the certification logic block 245 and the identification ID2 of the signature display logic 237 may comprise full path name descriptions for locating the logic on the computer system through use of the operating system, depending on the operating system implementation. The identifications ID3, ID4 of the data to certify typically comprise a data pointer. Although the display 200 is shown as a video display for purposes of illustration, the display 200 may also be a printer, plotter, or other means of displaying digital data.
One skilled in the art will appreciate that the data blocks stored on machine-readable medium 230 need not be stored in any particular arrangement with respect to one another. Also, within the data block 247 the first certificate 253 and second certificate 255 can be stored in any arrangement. Within each certificate, the signature and dynamic link blocks may be stored in any arrangement.
The machine-readable medium 230 may be a hard disk, a Random-Access-Memory (RAM), a cache memory, a Read-Only-Memory (ROM), a flash memory, or any other form of memory device which is capable of storing data and code which is executed by a processor element 220. In this example the machine-readable medium 230 and the processor 220 are shown as separate elements, however, one skilled in the art of computer systems will readily appreciate that they may be combined into a single integrated device, such as with on-chip flash memories. One skilled in the art will also appreciate that bus element 240 may be implemented in numerous ways familiar in the art of processor system design, for example, using an electrically conductive material, or using optical coupling.
Although this invention has been shown in relation to a particular embodiment, it should not be considered so limited. Rather, the invention is limited only by the scope of the appended claims. | The invention is a machine-readable medium for implementing an improved electronic transaction model. The machine-readable medium stores at least one non-certificate data block, at least one prior certificate, and a new certificate, the new certificate certifying a combination of less than all of a union of the at least one non-certificate data block and the at least one prior certificate. | 7 |
BACKGROUND
[0001] The present invention relates to the field of graphical user interfaces and, more particularly, to drag-and-drop actions for Web applications using an overlay and a set of placeholder elements.
[0002] Drag-and-drop is the ability to move graphical user interface (GUI) objects by means of manipulating a mouse or other pointing device (e.g., trackball, touchpad, etc.). In many implementations, while a selected object is being dragged, a GUI usually shows a visual representation of the dragged object under the mouse cursor. This permits a user to “see” the object being dragged as the pointer is dynamically moved on the screen. The visual representation of the dragged object is referred to hereafter as an “avatar”.
BRIEF SUMMARY
[0003] One aspect of the disclosure is for a Web application able to be executed and interactively presented within a Web browser. The Web application can include a set of graphical objects, an overlay, and a set of placeholder elements. The graphical objects can include at least one source object and a set of set of drop targets. The source object can be an object able to be dropped at any of the drop targets via a drag-and-drop action. The overlay can be positioned on top of the graphical objects as determined by a z-order of the Web browser. The overlay can be non-visible and can include an onmousemove event handler. The placeholder elements can be on the overlay. Each of the placeholder elements can be non-visible and can be positioned directly on top of a corresponding drop target. Each placeholder element can have a width approximately equal to a visible width of the corresponding drop target and a length approximately equal to the visible length of the corresponding drop target.
[0004] Approximately equal in this context represents a length and width determined to be “natural” for sensitive region of the drop target. For example, the placeholder width and height can be greater than the drop target to give extra leeway for dropping objects. Similarly, the width and height can be smaller than the drop target to prevent inadvertent dropping of a dragged object on the wrong target.
[0005] Each of the placeholder elements can also include an onmousemove event handler and an onmouseout event handler. The onmousemove and onmouseout event handlers of the placeholder elements can be utilized by the Web application to track which drop target, if any, a GUI pointer is positioned over.
[0006] Another aspect of the disclosure is for a method, computer program product, system, and apparatus for handling drag-and-drop actions in a Web application presented in a Web browser. In this aspect, an initiation of a drag-and-drop action can be detected, where the drag-and-drop action occurs in a graphical user interface of a Web application that is visually presented in a Web browser. The graphical user interface can include a set of graphical objects and a set of at least one drop targets. Responsive to the initiation of the drag-and-drop action, a previously deactivated overlay and a set of at least one placeholder elements can be activated within the graphical user interface. If activated, the overlay and set of placeholder elements can be positioned in the z-order of the graphical user interface on top of each of the graphical objects. If deactivated, the overlay and set of placeholder elements will not be positioned in the z-order of the graphical user interface on top of each of the graphical objects. The overlay and the placeholder elements can be non-visible at a time of activation. Each of the placeholder elements can be positioned directly on top of a corresponding drop target and can have a width approximately equal to a visible width of the corresponding drop target and a height approximately equal to a visible height of the corresponding drop target. Movement of a pointer in the graphical user interface can be tracked with an event handler of the overlay. Which drop target, if any, that the pointer is positioned over can be tracked using event handlers of the set of placeholder elements. Responsive to a completion of the drag-and-drop event, the overlay and the set of placeholder elements can be deactivated.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0007] FIG. 1 is a system that handles drag-and-drop actions for a Web application using an overlay and placeholder elements in accordance with an embodiment of the disclosure.
[0008] FIG. 2 shows a flow chart for a method for handling drag-and-drop actions using an overlay and placeholder elements in accordance with an embodiment of the disclosure.
[0009] FIG. 3 shows a screen within with drag-and-drop actions are performed using an overlay and placeholder element set in accordance with an embodiment of the disclosure.
DETAILED DESCRIPTION
[0010] One problem with a conventional drag-and-drop technique is that the drop target can be hidden under other objects. Should this happens, a user may have to stop the dragging, make both the source object and the drop target visible and start again.
[0011] Numerous performance issues exist for performing drag-and-drop actions in a Web application presented within a Web browser. For example, if JavaScript (TM) is used to track mouse movement and determine whether a dragged GUI object has been dropped (as well as to optionally move the avatar with the GUI pointer), the JavaScript (TM) must execute repeatedly for every increment that the mouse is moved. The computing resources consumed by the mouse-tracking JavaScript (TM) for drag-and-drop actions can be expensive, as JavaScript (TM) is interpreted. Thus, an end user may experience slow updates, delays as JavaScript (TM) is loaded for each page visit, and other negatives that detract from the overall user experience.
[0012] Known solutions to the JavaScript (TM) performance problems all have significant drawbacks. For example, a browser's built-in onmouseover and onmouseout events can be used on target elements to track mouse movement for drag-and-drop actions. If this approach is used, an avatar cannot be placed directly under a GUI pointer, as the avatar will prevent the onmouseover and onmouseout events from firing on the underlying drop targets (in other words the drop targets can be hidden by the avatar). Use of the browser's onmouseover and onmouseout events can be problematic if iframes are included on a page, as iframes can consume mouse events so that the mouse position cannot be accurately tracked. Additionally, problems can exist with hovers, tooltips, and mouse-over highlighting of elements being inadvertently triggered while an object is being dragged over other objects of a Web page.
[0013] The disclosure provides a solution for drag-and-drop operations within a Web browser. The solution relies on drop targets, an overlay, and placeholder elements. More specifically, drop targets on a page can be identified, where each drop target is a region to which a source object can be dragged via a drag-and-drop action. If a drag-and-drop action is initiated, a non-visible overlay can be placed on top of the z-order (e.g., z-stack) of a graphical user interface. Thus, the overlay will shield content below the overlay from responding to mouse movements, which prevents inadvertent hovers, tooltips, and mouse-over highlighting. Further, problems related to iframes can be prevented using the overlay. An avatar can be positioned under the overlay so that it does not consume any mouse events (i.e., the mouse events all go to the overlay, which has the onmousemove handler). The avatar can be placed in any desired position relative to the GUI pointer and can be moved as the GUI pointer is moved.
[0014] Placeholder elements, which are also not visible, can be defined at positions that correspond to each of the drop targets. Mouseover and mouseout events of the placeholder elements can be used to determine whether a GUI pointer is positioned above any of the drop targets or not.
[0015] As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system, method or computer program product. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” or “system.” Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer readable medium(s) having computer readable program code embodied thereon.
[0016] Any combination of one or more computer readable medium(s) may be utilized. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.
[0017] A computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.
[0018] Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing. Computer program code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the “C” programming language or similar programming languages. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).
[0019] Aspects of the present invention are described below with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.
[0020] These computer program instructions may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks.
[0021] The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.
[0022] FIG. 1 is a system 100 that handles drag-and-drop actions for a Web application 140 using an overlay 170 and placeholder elements 181 , 182 , 183 in accordance with an embodiment of the disclosure. For example, the overlay 170 can track mouse movement, which is used to properly position an avatar and other mouse movement related events. An avatar can be a visual representation of an object being dragged during a drag-and-drop action. The placeholder elements 181 , 182 , 183 can correspond to drop targets of a Web page 142 and can be used to determine whether a source object is dropped on any of these drop targets at a time a drag-and-drop action is being performed.
[0023] In system 100 , a computing device 110 can execute a Web application 140 . The Web application 142 can be conveyed to device over a network 102 , such as being served from Web server 104 . Web application 142 can also be accessed from a data store 106 , which can be a networked data store or a local storage device. The Web application 140 can include a set of Web pages 142 , 143 , 144 , which are linked to each other.
[0024] A drag-and-drop action, as noted by drag-and-drop code 190 , can be an action that includes a sequence where (1) a graphical object 151 , 152 , 153 is grabbed (code 192 ) using a pointing device 126 , (2) where the grabbed object is dragged (code 193 ) across a screen of the display 127 , and where the object is then dropped (code 194 ) on a drop target. This sequence results in a drag-and-drop event firing (code 195 ) where the source object (the object grabbed) is considered having been dropped at the drop target.
[0025] The computing device 110 can be include a personal computer, a notebook computer, a netbook, a smart phone, a kiosk, a home internet appliance, an embedded system, an entertainment console, a navigation system, a media player, and the like. Device 110 can include hardware 120 and software 130 , where the software can be stored on a non-transient storage medium, such as a memory 123 . Memory 123 can be a volatile or nonvolatile storage space for containing digitally encoded data. Hardware 120 can also include a bus 124 , which communicatively links device 110 components, such as processor 122 , memory 123 , network interface card 125 , pointing device 126 , display 127 to each other. Other components (not shown) are contemplated.
[0026] Pointing device 126 can be a mouse, trackball, touchpad, “air-mouse” or other such device able to direct a GUI pointer (e.g., arrow) presented on a graphical user interface. The pointing device 126 can also permit “click” events to occur, such as by actuating a button on the pointing device. In one embodiment, the pointing device 126 can permit “right click”, “left click” and scroll events.
[0027] Each of the software 130 items can also be referred to as a computer program product. The software 130 can include any set of computer readable instructions able to be stored on a memory and able to cause the processor 122 to perform a set of actions. Software 130 can include an operating system 132 , a graphical user interface (GUI) manager 133 , and a Web browser 134 .
[0028] The Web browser 134 can be an application able to execute Web application 140 , which includes an ability of the Web browser 134 to interactively render Web pages 142 , 143 , 144 . Web browser 134 can include a dynamic code interpreter 135 , a markup interpreter 136 , an event engine 137 , a z-order list 138 , and a graphical user interface 139 . The graphical user interface 139 can interactively present Web application 140 to a user, once the Web application 140 is loaded into the Web browser 134 . Interface 139 can be visually presented on the display 127 and can respond to input from pointing device 126 .
[0029] Page example 150 shows some of the elements defined for at least a portion of the Web pages 142 - 144 of the Web application 140 . The Web page of example 150 can include a set of elements, such as GUI objects 151 , 152 , 153 (also labeled Object A, Object B, . . . Object N). These GUI objects 151 - 153 are able to be presented in the GUI 139 , once loaded by Web browser 134 . The GUI objects 151 - 153 can include objects that are able to be a source object and drop targets for a drag-and-drop action. Each of the GUI objects 151 - 153 can include a number of properties, such as a position 156 , width 157 , height 157 , and z-index 159 .
[0030] The set of GUI objects 151 - 153 can be presented in an object region 160 of the GUI 139 . The object region 160 has an initial position 162 , as well as a width 163 and height 164 . Thus, none of the GUI objects 151 - 153 have presentation or positional values outside the object region 160 .
[0031] Overlay 170 having a set of position elements 181 - 183 can be included in the Web page shown by example 150 . The overlay 170 can have an onmousemove handler 172 , an onmouseup handler 173 , position 174 , width 175 , and height 176 , z-index 177 , and a transparency 178 value. The position, width, and height values 174 - 176 can be set to ensure the overlay 170 covers the object region 160 . The “coverage” of the object region 160 should cover at least the entire visible region of the GUI interface 139 . That is, it is possible for the overlay 170 to not fully cover the object region 160 , so long as all visible portions of the region 160 are covered, where visible portions refer to the region of a screen that the pointing device 126 is able to navigate to.
[0032] The overlay 170 can be non-visible, which can be accomplished by setting its transparency value 178 to 100 percent or to a fully transparent value. Additionally, a z-index value 177 for the overlay 170 can be set higher than any z-index value of the GUI objects 151 - 153 . This ensures that the overlay 170 is placed in the z-order list 138 on top of any of the GUI objects 151 - 153 . The overlay 170 includes an onmousemove handler 172 . Since the overlay 170 has a z-index 177 above other objects 151 - 153 of the Web application 140 , mouse movements can be tracked using the handler 172 without concern of other objects 151 - 153 intercepting the mouse movement events.
[0033] For example, even if one of the GUI objects 151 - 153 were an iframe (which consumes mouse position), the onmousemove handler 172 will not be affected, as the iframe has a z-index value below z-index value 177 of the overlay 170 . Further, the overlay 170 can shield the user interface 139 during a drag-and-drop action to ensure that tool-tips, hovers, GUI pointer highlighting, and other mouse-over effects are disabled on underlying GUI objects 151 - 153 .
[0034] The overlay 170 can include a number of placeholder elements 181 - 183 . Each placeholder element 181 - 183 can correspond to one of the GUI objects 151 - 153 . For example, GUI Object A ( 151 ) can correspond to Placeholder Element A ( 181 ); GUI Object B ( 152 ) can correspond to Placeholder Element B ( 182 ); and, GUI Object C ( 153 ) can correspond to Placeholder Element C ( 183 ). Each placeholder element 181 - 183 can have position 185 , width 187 , and height 188 values that ensure the corresponding GUI object 151 - 153 is covered by the placeholder element 181 - 183 . Additionally, each placeholder element 181 - 183 can include a transparency 168 attribute set to one hundred percent or to fully transparent. In one embodiment, the z-index value 189 of each position element 181 - 183 can be equivalent to the z-index value 178 of the overlay 170 . In one embodiment, the position elements 181 - 183 can be positioned above the overlay 170 (e.g., can have a higher Z-index value) to ensure they are not shielded by the overlay 170 .
[0035] Example page 150 can include drag-and-drop code 190 , which controls drag-and-drop actions for the Web application 140 . The drag-and-drop code 190 enables grabbing objects 192 , such as source objects, via the pointing device 126 ; dragging objects 193 ; and, dropping objects 194 . Code 190 also fires events 195 that occur in response to a drag-and-drop action being completed. Additionally, overlay code 196 can control the enablement, disablement, and placement of the overlay 170 . Placeholder code 197 can control creation, deletion, position, enablement, disablement, and the like of the placeholder elements 181 - 183 . Avatar code 198 controls presentation of an avatar during a drag-and-drop event.
[0036] The drag-and-drop code 190 can be Dynamic Hypertext Markup Language (DHTML) code that is interpreted by the dynamic code interpreter 135 . For example, code 190 can be JavaScript (TM) code in one embodiment. Code 190 can also utilize Cascading Style Sheets (CSS) and Document Object Model (DOM) standards. In another example, the drag-and-drop code 190 can be written in ActionScript, Caja, JScript, Objective-J, QtScript, WMLScript, ECMAScript, and the like.
[0037] In one embodiment, code 190 , or a portion thereof, can be incorporated into the software 130 instead of being defined within the Web application 140 . For example, the GUI manager 133 can implement grab 192 , drag 193 , drop 194 , and/or fire event 195 portions of the code 190 . Additionally, in one embodiment, the Web browser 134 can incorporate code 190 portions, such as incorporating the overlay 196 code, placeholder code 197 , and/or Avatar code 198 . In one embodiment, the code 190 or a portion of the code 190 can rely on server-side scripting languages, which can include PHP, Perl, JSP, ASP.NET, and the like.
[0038] The markup interpreter 136 of browser 134 can interpret the various markup elements of Web application 140 . For example, markup interpreter 136 can support Standard Generalized Markup Language (SGML), Hypertext Markup Language (HTML), Extensible Markup Language (XML), Extensible Hypertext Markup Language (XHTML), and other markup languages.
[0039] Event engine 137 can handle pointing device 126 actions for Web application 140 . Additionally, event engine 137 can enable the onmousemove handler 172 , the onmouseup handler 173 , the onmouseover handler 184 , and the onmouseout handler 185 .
[0040] The z-order list 138 determines an order that objects of the Web application 140 are stacked relative to each other. Thus, the z-order list 138 stacks objects 151 - 153 , overlay 170 , placeholder elements 181 - 183 in accordance with their respective z-index values (e.g., 159 , 177 , and 189 ).
[0041] FIG. 2 shows a flow chart for a method 200 for handling drag-and-drop actions using an overlay and placeholder elements in accordance with an embodiment of the disclosure. The method 200 can be performed in the context of system 100 in one embodiment.
[0042] The method 200 can begin in step 205 , where an overlay with placeholder elements can be deactivated. “Deactivated” means that the overlay with placeholder elements is not above GUI objects (like source and target objects) in the z-order. For example, the overlay and the placeholder elements may not be instantiated within a GUI at step 205 . In this context, “deactivated” can also mean that domain object model (DOM) nodes have not yet been created, or that they are not attached to the HTML document node, or that they are made invisible (e.g., using the display: none CSS style, for example). In one embodiment, the GUI being referenced can be a GUI of a Web application, which is rendered within a Web browser.
[0043] In step 210 , a GUI object can be selected via a pointing device. Selection can result in a visual indicator being shown, such as showing an icon being highlighted or color inverted. The selected GUI object can be considered a source object, which is an object able to be dragged from one location of a screen to another. In step 215 , a check can be made to see whether a mousedown action is being maintained, which represents an initiation of a drag-and-drop action. If not, GUI actions can continue as normal, as represented by step 220 .
[0044] Once a drag-and-drop action is initiated, the method progresses to step 225 , where a set of drop targets can be determined for the selected GUI object (e.g., source object). Different source objects can have different drop targets. In step 230 , a determination can be made as to whether an overlay object region is sufficient to cover the object region of the drop targets (which region may also include said source object). In step 235 , the overlay region can be adjusted to cover the object region, if necessary. Adjusting the overlay region can include adjusting a width, height, and/or position of the overlay.
[0045] In step 240 , for each drop target, a corresponding placeholder element can be established that covers the drop target. In step 245 , the overlay with placeholder elements can be activated. Upon activation, the overlay and placeholder elements can be invisible (e.g., fully transparent) and the z-index value of the overlay and placeholder elements can be greater than the z-index value of any of the other GUI objects on the GUI.
[0046] In step 250 , an avatar can be shown and displayed in a suitable position relative to the GUI pointer. In step 255 , a check can be made to see whether a source object has been dragged. This check can be based on mouse movements occurring with a mousedown action being maintained. If the source object was dragged, step 260 can be performed, where the avatar can be moved to a proper position relative to the GUI pointer.
[0047] In step 265 , onmouseover and onmouseout events of the placeholders can be listened for. On each mouseover, the method can determine which placeholder it is over and can update the current drop target to the one that corresponds to the placeholder. On a mouseout event, the current drop target can be cleared. If a mouseup does not occur in step 270 , the method 200 can proceed from step 270 to step 255 . In one embodiment, the mouseup action can be determined using an onmouseup handler of the overlay.
[0048] If the GUI pointer is above a drop target in response to the mouseup occurring, step 275 can execute, where the source object is dropped on the drop target. Then a suitable drag-and-drop action can be performed. If the mouseup occurs and the GUI pointer is not above a drop target, a suitable action can occur in step 280 . For example, the drag-and-drop can be canceled in step 280 .
[0049] In step 285 , the overlay with placeholder elements can be disabled. In step 290 , the avatar can be hidden or no longer displayed. The method can proceed from step 290 to step 220 , where additional GUI interactions can continue to occur.
[0050] FIG. 3 shows a screen 310 within with drag-and-drop actions are performed using an overlay and placeholder element set in accordance with an embodiment of the disclosure. The screen 310 can be a screen rendered within a Web browser, such as being a Web application. A set of different states (state 302 - 307 ) are shown in FIG. 3 for the screen 310 .
[0051] In state 302 , a user can position a GUI pointer 318 above a source object 314 and can then select the object 314 , such as by performing a left-click action on a pointer device. Selection of the source object 314 can cause the source object 314 to visibly change, such as highlighting the object 314 to indicate selection. Selection of the source object 314 can be a “grab” phase of a drag-and-drop action. Possible drop targets for the source object 314 , as shown in screen 310 , include a trash drop target 322 , a Folder A drop target 324 , a Folder B drop target 326 , and a printer drop target 328 .
[0052] Initiating the drag-and-drop action causes the screen 310 to progress to state 303 , where an overlay 331 and placeholder elements 332 , 334 , 336 , 338 are activated. The overlay 331 and placeholder elements 332 - 338 can be fully transparent and can placed on top of other GUI objects 314 , 322 - 328 . Once activated, overlay 331 and placeholder elements 332 - 338 shield the GUI objects 322 - 338 , and 314 from mouse events. More specifically, the overlay 331 can have an onmousemove handler and onmouseup handler and the placeholder elements 332 - 338 can have onmouseover and onmouseout handlers.
[0053] Once the overlay 310 and placeholder elements 332 - 338 are activated, the screen can be placed in state 304 , where the GUI pointer 318 can be moved. Additionally, an avatar 340 for the source object 314 can be shown in a position relative to the GUI pointer 318 . In response to movement of the GUI pointer 318 (as determined by the mousemove events detected by the onmousemove handler of the overlay 331 ), the avatar 340 can move in a corresponding fashion.
[0054] The GUI pointer 318 can move until it is dragged over a drop target, such as Folder A, which is shown in state 305 . Next, a mouseup action (or some other action that releases the avatar) can occur. Then, the drag-and-drop action can fire, and the avatar 340 can disappear, as shown by state 306 . Further, completion of the drag-and-drop action can cause the overlay 331 and placeholder elements 332 - 338 to be deactivated, which causes the drop targets 322 - 328 to be on top of the z-order again, as shown by state 307 .
[0055] The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. | In order to improve performance and responsiveness for drag-and-drop actions for Web applications, the amount of JavaScript loaded and executed at each increment of the mouse as it moves during a drag-and-drop action should be minimized. This can be achieved by harnessing the efficient and native-code algorithms built into Web browsers. Instead of using a JavaScript algorithm to compute which drop target the mouse is on, an overlay with placeholders can be placed on top of the page using z-index, where the placeholders are placed directly on top of the drop targets. The current drop target can be computed using the browser's built-in onmouseover and onmouseout events on the placeholder elements, thus freeing the browser from loading and executing too much JavaScript. | 6 |
[0001] This application claims the benefit of application Ser. No. 13/085,175 filed on Mar. 12, 2011 entitled “Method and Apparatus for Reducing CO 2 in a Stream by Conversion to a Syngas for Production of Energy,” which is a continuation-in-part of application Ser. No. 13/070,586, filed on Mar. 24, 2011, entitled “Method and Apparatus for Reducing CO 2 in a Stream by Conversion to a Syngas for Production of Energy,” respectively are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates generally to the field of reducing the carbon dioxide in a gaseous stream, such as the exhaust stream from cement plants, power plants and other types of industrial plants, and more specifically to the use of a unique process of reducing the carbon dioxide to concurrently form Syngas (primarily CO 2 +H 2 ). The syngas can, in turn, be used in the production of energy in the form of various fuel sources, such as for example only, Ethanol, Methanol, Diesel and jet Fuel.
BACKGROUND
[0003] Concern about global warming eventually leads to discussions about the need to reduce the amount of carbon dioxide that pours into the earth's atmosphere on a daily basis from power plants and other industrial factories. At the same time, concerns about dwindling supplies of fossil fuels have encouraged the development of other types of liquid fuels, such as Ethanol, as replacement fuels. Unfortunately, many of the present methods of producing a liquid fuel such as Ethanol require expensive farm produce such as, for example, corn and almost all of these alternate methods result in about as much or more carbon dioxide being introduced into the atmosphere as does burning fossil fuels.
[0004] Therefore, a method for producing syngas, (easily convertible to Ethanol and other fuels) from the CO 2 in gaseous streams that are exhausted by industrial plants would offer many advantages in cost, as well as, a significant overall reduction in the carbon dioxide dumped into the atmosphere.
SUMMARY OF THE INVENTION
[0005] The present invention discloses methods and apparatus for reducing and forming syngas from the significant quantities of carbon dioxide that is often present in gaseous streams exhausted or emitted from power plants and various types of industrial plants that use fossil fuels, such as, for example, a cement plant. As an example only, the typical cement production plant will have a total gaseous exhaust stream of about 400,000 lbs/hr. The exhaust stream will typically contain about 30%-40% (about 160,000 lbs/hr) of carbon dioxide (CO 2 ), 55%-60% (231,000 lbs/hr) of nitrogen (N 2 ); around 2% (7,800 lbs/hr) of oxygen (O 2 ) and small amounts of other constituents. However, according to this invention, instead of the CO 2 contained in such a gaseous stream being exhausted to the atmosphere or collected and disposed of by methods such as sequestration, the gaseous stream is provided to a reaction chamber, such as, for example, a Plasma Arc Gasification Chamber or a Pyrolysis Chamber along with the additional reactants, carbon and H 2 O. Reactions are then initiated in the reaction chamber, typically without the assistance of a catalyst, and significant amounts of the CO 2 in the gaseous stream are converted to commercially usable syngas (carbon monoxide and hydrogen (CO+H 2 )).
[0006] In a computer simulated test run of the invention using the above example as the gaseous stream, the amount of carbon dioxide in the gaseous stream is reduced from 160,000 lbs/hr to about 75,195 lbs/hr plus a significant amount of syngas. This is a reduction in carbon dioxide of about 53% and depending on the content or make up of the gaseous stream, some form of vitrified slag or ash will also usually be present. Actual test runs, which were severely limited by the capabilities of the reaction chamber and other equipment, have still resulted in reductions of carbon dioxide of 67% and predictive calculations indicate reductions the process of this invention can achieve a reduction of the carbon dioxide above 90%.
[0007] Therefore, it is clear that the process of the present invention significantly reduces the amount of CO 2 (carbon dioxide) in a reaction chamber. Further, as mentioned above, the process also generates substantial amounts of syngas from the reduction or conversion of the CO 2 . The syngas can then be converted to various types of fuels such as ethanol. Briefly, the process comprises maintaining the reaction chamber at a pressure of about one bar or greater and at a temperature of between about 1500° F. (815.6° C.) to about 3000° F. (1649° C.), and preferably at about 2426° F. (1330° C.). A gaseous stream containing the carbon dioxide (CO 2 ) is provided to the reactor at a first selected rate along with carbon (C) that is provided at a second selected rate. The mass ratio of the rate of providing carbon with respect to the rate of providing CO 2 being between about 0.100 and 0.850, and preferably between about 0.200 and about 0.700. H 2 O (steam) is also provided to the reaction chamber at a third selected rate, wherein the mass ratio of the provided H 2 O/steam with respect to the provided CO 2 rate is between about 0.200 and 0.500, and preferably between about 0.250 and 0.450. The carbon is then reacted with the H 2 O/steam and the carbon dioxide (CO 2 ) in the gaseous stream and results in a reduction of the CO 2 by at least 30% to concurrently form syngas comprising carbon monoxide (CO) and hydrogen (H 2 ). The selected rate at which the carbon, the CO 2 and the H 2 O/steam is provided is controlled such that substantially all of the carbon exiting the reaction chamber in said syngas is combined with O 2 , H 2 O, and CO 2 to primarily produce CO and H 2 . That is, substantially no carbon (C) exits the chamber in the syngas that is not combined.
[0008] The syngas can then be cleaned, if necessary, and used as a feedstock for the production of ethanol and/or other fuels. For example, a bio-chemical process or a Fischer-Tropsch (F-T) process could be used to produce the ethanol.
[0009] As mentioned above, the process for reducing the carbon dioxide and forming the syngas according to this invention consists essentially of maintaining a reaction chamber, such as a pyrolysis chamber or a plasma arc chamber, at a temperature of between about 1500° F. (815.6° C.) and 3000° F. (1649° C.) and preferably at about 2426° F. (1330° C.) with a pressure of about one atmosphere or greater. It will be appreciated that some of the reactions in the chamber are endothermic and therefore, regardless of the type of reaction chamber used, additional heat may be required. Therefore, Plasma Arc or Pyrolysis chambers are at present the preferred choices for use as the reaction chamber. However, a conventional gasifier reactor, or a gasification reactor are also believed to be suitable.
[0010] According to the invention, in addition to the CO 2 (carbon dioxide) a source of carbon (C) including carbonaceous materials such as charcoal, coal, coke, or solid or bio waste, etc., is present in a reactor that is operating at sufficient temperatures such that a Boudouard reaction (i.e., C+CO 2 ⇄2CO) takes place. Further, as will be discussed later, it should also be understood and appreciated that the use of higher temperatures in the reaction chamber avoids the serious problem of carbon formation and deposition of the formed carbon on chamber walls and in and on items in the chamber. In addition, an although a catalyst is not required according to the present invention, if it is determined that the presence of a catalyst in the chamber can improve the effectiveness of the process, it will be appreciated that since there is substantially no elemental carbon formation in the reaction chamber with the process of this invention, there can be no carbon formed that will be deposited on the chamber walls or that could form on and deactivate the catalyst. As is well known to those skilled in the art catalyst deactivation due to carbon deposits is a common problem with reaction chambers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:
[0012] FIG. 1 is a block diagram illustrating the processes of the present invention;
[0013] FIG. 2 illustrates the inputs and outputs of the reactor of the invention;
[0014] FIG. 3 illustrates predictive curves that compare the CO 2 reduction to input ratios C/CO 2 , H 2 O/CO 2 and O 2 /CO 2 ;
[0015] FIGS. 4-7 represent second order curves prepared from the data of Tables 9-1 and 9-2;
[0016] FIG. 8 is a graph of nine test results of the present invention showing ratios of various input materials with respect to the carbon dioxide (CO 2 ) input gaseous stream and resultant CO 2 fraction-reduced in feed;
[0017] FIG. 9 is a graph showing the percentage of CO 2 reduction and the amount of syngas [Carbon monoxide (CO)+Hydrogen (H 2 O)] generation in lbs/hr for each of the nine test runs;
[0018] FIG. 10 is similar to FIG. 1 , but includes a Gasifier of a presently available process for the gasification of municipal solid waste to Syngas. The syngas, in turn, provides the output power (e.g., electricity, steam and/or heat) to the pyrolysis reactor of the present invention that reduces the CO 2 and generates syngas from the conversion of the CO 2 ;
[0019] FIG. 11 illustrates the process of FIG. 1 , 2 or 10 combined with another process for the production of Ethanol; and
[0020] FIG. 12 , which includes FIGS. 12 a and 12 b , is a detailed example of FIG. 11 illustrating the use of a first and a second bio-catalytic reactor.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0021] The presently preferred embodiments are discussed in detail below. It should be appreciated, however, the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative of specific ways to make and use the invention, and are not intended to limit the scope of the invention.
[0022] Referring now to FIG. 1 , there is illustrated a simplified block diagram of the present inventive process. As shown, a reaction chamber 10 receives a source of carbon (C), H 2 O (steam), and a source of carbon dioxide (CO 2 ). The source of CO 2 may typically be provided by a gaseous stream, such as exhaust gases from an industrial plant or facility that contain a significant amount of carbon dioxide (CO 2 ), as indicated by line 12 . As examples only, the source 14 of the carbon dioxide or CO 2 could be from a fossil fuel power plant or from substantially any industrial gaseous exhaust stream, such as, a rotary kiln type cement plant, a refinery, an ethanol plant, a utility power plant, etc. As a more specific example, the gaseous stream from a rotary kiln will typically comprise between about 55% to about 70% nitrogen (N 2 ) and about 45% to about 30% carbon dioxide (CO 2 ) and possibly minute amounts of oxygen (O 2 ) and other impurities. It will also be appreciated, of course, that although exhaust gases from an industrial plant is considered an excellent source of carbon dioxide, a source of pure carbon dioxide would also be suitable and would simplify the process. In the embodiment of FIG. 1 , the reaction chamber 10 is illustrated as a pyrolysis reactor, but a conventional gasifier may also be suitable, and alternately, to avoid the introduction of excessive O 2 , a plasma arc chamber that uses an ionized gas with minimal or no oxygen may be preferable.
[0023] In prior art processes that use a pyrolysis reaction or process for the gasification of coal, or the reforming of methane, the formation of carbon deposits in the reaction chamber must be carefully avoided so that such deposits will not form on the catalyst to maintain the catalyst at its maximum effectiveness. Such carbon formation and deposits are typically avoided in these prior art processes by maintaining the reaction chamber at a low temperature such as between 600° C. (1112° F.) and 850° C. (1562° F.), although there have been some reports of using a temperature of 982° C. (1800 F) in a reaction chamber for coal gasification. It should be understood, however, there is no known reports of using such a high temperature for the purpose of converting carbon dioxide to syngas. (See Choudhary, et.al., “Simultaneous steam and CO 2 reforming of methane to syngas over NiO/MgO/SA-5205 in the presence and absence of oxygen”, 1998, Applied Catalyst A: General, no 168, pp 33-46; Lemonidou et.al., “Carbon dioxide reforming of methane over 5 wt. % Ni/CaO-A12-03 catalyst”, 2002, Applied Catalyst A: General, no 228, pp. 227-235; and U.S. Pat. No. 5,937,652 issued to Fawzy T. Abdelmalek, August, 1999). As will be appreciated by those skilled in the art, the conditions in a reaction chamber are typically at about one atmosphere or one bar, but can be higher. Further, in the prior art and as mentioned above, reaction chamber temperatures of between about 600° C. and 850° C. are typical for coal gasification, but not for the purpose of converting carbon dioxide to syngas.
[0024] A primary chemical reaction that will take place in a reaction chamber containing carbon dioxide (CO 2 ) and a source of carbon (C) in the absence of free oxygen is believed to be the reaction of carbon (C) in the carbonaceous material with the carbon dioxide (CO 2 ) according to:
[0000] C+CO 2 2CO, Equation (1)
[0000] that is often referred to as a Boudouard reaction.
[0025] If H 2 O (typically in the form of steam) is also available in the reaction chamber 10 , other reactions that can occur in the reaction chamber may include:
[0000] C+H 2 O CO+H 2 , Equation (2)
[0000] often referred to as gasification with steam;
[0000] CO+H 2 O H 2 +CO 2 , Equation (3)
[0000] referred to as a water-gas shift reaction; and
[0000] C n H m +n H 2 O n CO+( n +½ m )H 2 , Equation (4)
[0000] representing steam reforming. In addition, if free Oxygen (O 2 ) is present from any source, including the Plasma Torch gas or in the carbon source, CO 2 may be reformed such that the total reduction of CO 2 will be decreased;
[0000] C+O 2 CO 2 Equation (5)
[0026] Importantly, in the present invention and as seen from the Boudouard reaction of Equation (1), the carbon (C) provided by the source 18 combines with one of the two oxygen (O) atoms in the carbon dioxide (CO 2 ) molecules to form two molecules of carbon monoxide (2CO). As will be appreciated by those skilled in the art, as indicated by Equation (2), if water (e.g. steam) is also present in the reaction chamber, the carbon (C) may also react with the water (H 2 O) to produce carbon monoxide and free hydrogen (H 2 ). The mixture of CO and H 2 is commonly referred to as syngas. It should also be appreciated, that all of the carbon dioxide (CO 2 ) in the gaseous stream may not be converted to carbon monoxide (i.e., CO). Further, as was discussed above and as will be discussed in more detail later, excess H 2 O (steam) may also react with some of the carbon monoxide (CO) to reform some carbon dioxide (CO 2 ) and some hydrogen (H 2 ) as indicated by Equation (3). Also, some of the carbon (C) may react with free oxygen O 2 to reform small amounts of CO 2 , and consequently, the exhaust from the reaction chamber will often contain and therefore discharge a reduced amount of carbon dioxide (CO 2 ) (indicated by block 26 ) along with the syngas as indicated on line 24 . Also, as shown, there will typically be a vitrified slag or ash product 28 produced by the process. The chemical content of the vitrified slag or ash will, of course, vary according to the elements in the carbonaceous source and the temperature of the reaction chamber.
[0027] However, unlike most prior art pyrolysis processes (a pyrolysis process is the thermal decomposition of organic material by heating in the absence of oxygen and other reagents or material: (except possibly steam) that will reduce the amount of carbon dioxide and form syngas), and until the applicants prior invention (See U.S. Pat. Nos. 7,923,476 and 7,932,298 incorporated herein by reference), the inter-reaction of these various reactions were not sufficiently understood, and therefore could not be controlled such that a significant amount of the CO 2 could be reduced and converted to syngas. The unique process of the present improvement invention defines unexpected effective ratios of carbon (C), carbon dioxide (CO 2 ) and H 2 O/steam for the reduction of the carbon dioxide CO 2 and uses reaction temperatures typically no lower than about 815° C. (1499° F.) and preferably about 1330° C. (2426° F.) up to 3000° C. (5432° F.) or even higher. Thus, by maintaining a temperature range in the reaction chamber 10 that is significantly higher than that typically used in prior art processes, along with the unique and proper ratios of C, CO 2 , and H 2 O, carbon deposits, which are a major problem with many pyrolysis reactions, are not formed in the chamber of the present invention even though, as indicated by line 16 , large quantities of carbon are required to be present in the reactor 10 to achieve the desired carbon dioxide reduction and the conversion to syngas by the pyrolysis reaction of this invention.
[0028] As discussed above, the source 18 of the carbon in the chamber may be various suitable carbonaceous materials such as charcoal, coke, coal, or even other hydrocarbon sources, such as biomass materials or municipal waste solids. In addition, as will be appreciated by those skilled in the art and as discussed above, since the pyrolysis reaction takes place at elevated temperatures, heat is provided as indicated at line 20 from an energy source 22 . The energy source may originate as electricity, steam or any other source that can generate heat energy. However, it is noted, that as suggested above and as will be discussed in more detail later, many energy sources for providing additional heat, may undesirably introduce additional oxygen into the chamber that will affect the efficiency of the process such that the ratio of the CO 2 , C, and H 2 O may need to be adjusted.
[0029] More specifically four different embodiments of computer simulation tests of the invention and shown as Table 1-Table 4 follow. The results according to a first computer simulation test of the invention are illustrated in Table 1 below as a first embodiment. This computer simulation test illustrates an embodiment wherein a reaction chamber 10 is maintained at a temperature of 1,330° C. (2,426° F.) and a pressure of 1.00 bars. The gaseous stream containing carbon dioxide, and other input materials of the simulation process are as shown below. Also shown is the expected syngas output according to the computer simulation model.
[0000]
TABLE 1
CHAMBER CONDITIONS 1330° C. AND 1.00 BAR
(Mole %)
(Weight %)
(K Mole/hr)
(Mole %)
(Weight %)
(K Mole/hr)
INPUT TO CHAMBER
SYNGAS FROM CHAMBER
FEED GAS
Nitrogen (N 2 )
56.52
52.13
0.680
45.79
47.44
0.680
Methane (CH 4)
0.08
0.04
0.001
0.00
0.00
0.00
Carbon
0.08
0.08
0.001
31.04
32.16
0.461
Monoxide (CO)
Carbon
24.94
36.13
0.300
9.49
15.46
0.141
Dioxide (CO 2 )
Hydrogen (H 2 )
0.08
0.01
0.001
7.07
0.53
0.105
Oxygen (O 2 )
1.67
1.75
0.02
0.00
0.00
0.000
OTHER INPUTS
Water (H 2 O)
16.63 (1)
9.86 (1)
0.200 (1)
6.61
4.41
0.098
Carbon (C)
0.300
0.000
TOTAL
100.00
100.00
1.503
100.00
100.00
1.485
(1) Includes moisture in original Gas stream plus any H 2 O to facilitate gasification.
[0030] The above embodiment illustrates that the feed gas provided to the chamber could be comprised of nitrogen, methane, carbon dioxide, hydrogen, water moisture in the gas and oxygen wherein the carbon dioxide in this feed gas is then converted to syngas by adding carbon and H 2 O (steam) to the chamber. The chamber should be maintained at a temperature of about 1,330° C. and 1.0 bar pressure. As shown, by this computer simulation, a substantial amount of the carbon dioxide (53%) will be converted to syngas under these chamber conditions. It should also be noted that the amount of carbon (C) introduced into the reaction chamber is controlled such that it is substantially fully reacted or combined as CO or CO 2 such that only minute amounts, if any, unreacted carbon (C) will be contained in the resulting generated syngas.
[0031] A second computer simulation test shows how an input of insufficient H 2 O and insufficient carbon results in a negative effect on the reduction of CO 2 and the amount of formed Syngas in the chamber. The second simulation test yielded the results shown in Table 2 below.
[0000]
TABLE 2
CHAMBER CONDITIONS 1330° C. AND 1.00 BAR
(Mole %)
(Weight %)
(K mole/hr)
(Mole %)
(Weight %)
(K Mole/hr)
INPUT TO CHAMBER
SYNGAS FROM CHAMBER
FEED GAS
Nitrogen
61.65
54.83
0.680
61.70
54.82
0.680
Methane
0.09
0.05
0.001
0.00
0.00
0.000
Carbon Monoxide
0.09
0.08
0.001
0.00
0.00
0.000
Carbon Dioxide
27.20
38.01
0.300
27.50
38.37
0.303
Hydrogen
0.09
0.01
0.001
0.00
0.00
0.000
Oxygen
1.81
1.84
0.020
1.45
1.47
0.016
OTHER INPUTS
Water (H 2 O)
9.07 (1)
5.18 (1)
0.100 (1)
9.35
5.34
0.103
Carbon (C)
0.001
0.000
100.00
100.00
1.103
100.00
100.00
1.102
(1) Includes moisture in the original gaseous stream plus water added to facilitate gasification.
Note:
The amount of carbon dioxide (CO 2 ) in the Syngas or exhaust output actually increased above the amount of (CO 2 ) originally in the Feed gas due to insufficient amounts of water and carbon in the feed to the chamber.
[0032] It is again noted that as in the above example, the carbon (C) provided to the chamber was controlled so that no unreacted carbon was in the generated syngas leaving the chamber. A third test shown in Table 3 also further illustrates the effect of insufficient H 2 O and insufficient carbon.
[0000]
TABLE 3
CHAMBER CONDITIONS 1330° C. AND 1.00 BAR
(Mole %)
(Weight %)
(K mole/hr)
(Mole %)
(Weight %)
(K Mole/hr)
INPUT TO CHAMBER
OUTPUT FROM CHAMBER
COMPONENT
Nitrogen
61.65
54.82
0.680
57.38
52.98
0.680
Methane
0.09
0.05
0.001
0.00
0.00
0.000
Carbon Monoxide
0.09
0.08
0.001
12.57
11.61
0.149
Carbon Dioxide
27.20
38.01
0.300
21.35
30.98
0.253
Hydrogen
0.09
0.01
0.001
10.41
0.10
0.0167
Oxygen
1.81
1.84
0.020
0.00
0.00
0.000
OTHER INPUTS
Water (H 2 O)
9.07 (1)
5.19 (1)
0.100 (1)
7.29
4.33
0.0864
Carbon (C)
0.100
TOTAL
100
1.203
100.00
100.00
1.1851
(1) Includes moisture in original gas steam plus water to facilitate gasification.
Note:
In the Syngas from the chamber, the Oxygen (O 2 ) content went to zero but the Carbon dioxide (CO 2 ) reduction was only 15.7%. Insufficient water and insufficient Carbon in the feed to the chamber resulted in the poor reduction of Carbon dioxide in the feed gas. Of course, since the amount of carbon (C) provided to the reaction chamber was not even sufficient to convert the CO 2 , there was no unreacted carbon in the resulting syngas.
[0033] Still another example of a simulated process of reducing the carbon dioxide in a gain a gaseous stream from a Corn-to-Ethanol production plant is as follows:
[0000]
TABLE 4
CHAMBER CONDITIONS 1330° C. and 3.08 bar
INPUTS TO
SYNGAS FROM
GASIFIER
GASIFIER
COMPONENT
Kmole/hr)
(Mole %)
(Kmole/hr)
(Kgram/hr)
FEED GAS
Nitrogen (N 2 )
0.0001
0.00
0.00
0.00
Methane (CH 4 )
0.0001
0.00
0.00
0.00
Carbon monoxide
0.0001
0.00
968.0
27,113.68
(CO)
Carbon dioxide
388.2
95.48
2.89
127.19
(CO 2 )
Hydrogen (H 2 )
Oxygen (O 2 )
0.0001
0.00
0.00
0.00
Water (H 2 O,
18.38
4.52
1.81
32.61
moisture)
SUBTOTAL
406.5805
100.00
OTHER INPUTS
Added H 2 O
180.38
Carbon
582.3
[0034] The above embodiment illustrates another embodiment, wherein the feed gas provided to the chamber is comprised of carbon dioxide, hydrogen, water (moisture), oxygen and minute amounts of methane and nitrogen. Similar to the previous embodiment shown in Tables 1-3, the carbon dioxide in the feed gas is converted to syngas by adding carbon and H 2 O (steam) to the chamber, except in this embodiment, the chamber operates at a 3.08 bars of pressure. It is also important to note that the target temperature of 1330° C. (2426° F.) was used in this simulation test. However, during the simulation test it was noted that, all of the carbon (C) is essentially depleted or used up in the conversion process to syngas. Therefore, a temperature of about 1330° C. may be a significant temperature. As shown, since almost all of the carbon dioxide (99.3%) will be converted, i.e., a reduction of Carbon Dioxide (CO 2 ) in the feed gas of 99.3%, and, of course essentially no carbon will be present in the exhaust or syngas.
[0035] The inventive concept illustrated by the computer simulated test runs discussed above for the conversion of carbon dioxide (CO 2 ) to syngas (CO and H 2 ) have been verified by actual tests carried out at a first Pilot Plant Plasma Gasification Reactor (PGR). The test parameters and results of these actual tests are set out in Tables 5-8 below. The weight amounts of the input and output parameters in Tables 5-8, are in different units of (lbs/hr), and represent the parameter units recorded at the pilot plant. FIG. 2 illustrates the equipment used for the first actual test run with inputs and outputs similar to the embodiment of Table 5. FIG. 2 is also appropriate for test runs represented by Tables 5-8 discussed later, except various ones of the inputs and consequently the outputs have changed. It should also be noted, that there was no measurable unreacted carbon (C) in the exhaust or syngas produced by the reaction in any of the test runs illustrated in Tables 5-8.
[0000]
TABLE 5
(Case 1)
OUTPUT FROM
GASIFIER
INPUTS
1950° F. (1066° C.)
TO GASIFIER
and 14.696 psia
COMPONENT
(SCFM)
(lb/hr)
(Vol %)
(lbs/hr)
Shroud CO 2
19.94
138.42
Torch Air
28.96
132.06
(Approximately
30.51 lbs/hr O 2 &
99.73 lbs/hr N 2 & Ar)
Nitrogen purge
5.0
21.95
Coke, 70 lb/hr total
63.70
at 91.0% Carbon
H 2 O (steam)
40.00
SYNGAS OUTPUT
Carbon monoxide (CO)
44.95
207.56
Carbon dioxide (CO 2 )
7.210
52.32
Hydrogen (H 2 )
18.76
6.19
Ar
0.10
0.66
Nitrogen (N 2 )
27.03
124.81
Oxygen (O 2 )
0.02
0.10
H 2 O
1.50
4.45
TOTAL (approximately)
396
396.
(402
(402
including
including
other output)
other output)
OTHER OUTPUTS:
Approximate output from
bottom of Gasifier: 6.27
lbs/hr Slag/Vitrified slag
Note:
213.75 lbs/hr of usable syngas (CO and H 2 ) and about 6.27 lbs/hr Slag/Vitrified slag was produced
Note:
The feed ratio of carbon (C) to CO 2 is 0.460 lbs/.lbs, and the feed ratio of Steam (H 2 O) to CO 2 is 0.289 lbs/lb. The feed ratio of total oxygen O 2 to CO 2 is 0.220 lbs/lb.
Note:
Water in = 40.00 lbs/hr or 2.22035 lbs-mole/hr; Carbon in = 63.70 lbs/hr or 5.30580 lbs-mole/hr; and Water out = 4.45 lbs/hr or 0.24701 lbs-mole/hr Such that % Water consumed/carbon in × 100 = [(2.22035 − 0.24701)/5.30580] × 100 = 37.2%
[0036] In this test, the CO 2 conversion rate was 64.0% (includes CO 2 generated in-situ of 7.0 lb/hr). However, the gasification temperature of 1950° F. was below the target temperature of 2426° F. because the plasma heat torch did not have the power to supply the desired energy to bring the chamber to the target temperature of 2426° F. It should also be noted that the reaction chamber incorporated a coke bed to supply the carbon that was depleted at a rate of six inches per hour, which translates to 70 lbs/hr.
[0037] Thus, as set out above, it is seen that at the completion of the process the carbon dioxide (CO 2 ) has been reduced by about 64.0%. As is well known, the input mass to the reactor must, of course, equal the mass output from the reactor. The inputs and outputs of the reaction chamber shown in Table 5 are clearly equal. Specifically, the total lbs/hr input equals approximately 396 lbs/hr and comprises 132.06 lbs/hr from torch air and 21.95 from purge N 2 ; 138.42 lbs/hr of CO 2 ; plus 63.70 lbs/hr of Carbon/Coke plus 40 lbs/hr of Water/Steam. Likewise, the mass output also equals approximately 396 lbs/hr and comprises 124.81 lbs/hr of N 2 (from torch air and purge) plus 207.56 lbs/hr of CO plus 6.19 lbs/hr of H 2 plus 52.32 lbs/hr of CO 2 and plus 4.45 lbs/hr of H 2 O and 0.10 lb/hr O 2 . No measurable uncombined carbon (C) was in the mass output. In addition, to the reduction of the CO 2 , the process resulted in 213.75 lbs/hr of CO plus H 2 , i.e., basic components of Syngas. Total Syngas production is 396 lbs/hr (105 SCFM). Even after clean up, the syngas provides a significant economic advantage, since as will be appreciated various bio-catalytic processes effectively use syngas and/or carbon monoxide (CO) as feed stock for organisms in bioreactors that produce Ethanol or may use a Fisher-Tropsch (F-T) synthesis process that converts syngas to Ethanol.
[0038] Three additional test runs according to the embodiment of FIG. 2 are shown in Tables 6-8, except the inputs and the resulting outputs have changed.
[0000]
TABLE 6
(Case 2)
OUTPUT FROM
GASIFIER
INPUTS
1900° F. (1038° C.)
TO GASIFIER
and 14.696 psia
COMPONENT
(SCFM)
(lb/hr)
(Vol %)
(lbs/hr)
Shroud CO 2
15.05
104.48
Torch Air
29.0
132.24
(Approximately
30.55 lbs/hr O 2 &
99.87 lbs/hr N 2 & Ar)
Nitrogen purge
5.0
21.95
Coke, 70 lb/hr total
63.70
at 91.0% Carbon
H 2 O (steam)
40.00
SYNGAS OUTPUT
Carbon monoxide (CO)
42.29
181.5
Carbon dioxide (CO 2 )
7.44
50.18
Hydrogen (H 2 )
20.33
6.23
Ar
0.10
0.61
Nitrogen (N 2 )
27.86
119.57
Oxygen (O 2 )
0.02
0.09
H 2 O
1.50
4.14
TOTAL (approximately)
362
362
(368
(368
including
including
other output)
other output)
OTHER OUTPUTS:
Approximate output from bottom of
Gasifier: 6.27 lbs/hr Slag/Vitrified slag
Note:
187.73 lbs/hr of usable syngas (CO and H 2 ) and about 6.27 lbs/hr Slag/Vitrified slag was produced.
Note:
The feed ratio of carbon to CO 2 is 0.610 lbs/lbs, and the feed ratio of Steam (H 2 O) to CO 2 is 0.383 lbs/lbs The feed ratio of total oxygen O 2 to CO 2 is 0.292 lbs/lbs
Note:
Water in = 40.00 lbs/hr or 2.22035 lbs-mole/hr; Carbon in = 63.7 lbs/hr or 5.3058 lbs-mole/hr; and Water out = 4.14 lbs/hr or 0.2298 lbs-mole/hr. Such that % Water consumed/carbon in × 100 = [(2.22035 − 0.2298)/5.30580] × 100 = 37.5%
[0039] In this test, the CO 2 conversion rate was 55.0% (includes CO 2 generated in-situ of 7.0 lb/hr). However, the gasification temperature of 1900° F. was again below the target temperature of 2426° F. because the plasma heat torch did not have the power to supply the desired energy to bring the chamber to the target temperature of 2426° F. This gasification temperature was 50° F. less than the temperature of Case 1 shown in Table 5. Also, as in Case 1, the reaction chamber used a coke bed to provide the carbon that was depleted at a rate of six inches per hour, which translates to a 70 lbs/hr flow rate.
[0040] Thus, as set out above, it is seen that at the completion of the process the carbon dioxide (CO 2 ) has been reduced by about 55.0%. As discussed above, the input mass to the reactor must, of course, equal the mass output from the reactor. The inputs outputs of the reaction chamber shown in Table 6 are clearly equal. Specifically, the total lbs/hr input equals approximately 362 lbs/hr and the total mass output also equals approximately 362 lbs/hr. It is again noted, there was no measurable uncombined carbon (C) in the output. In addition to the reduction of CO 2 , the process produces 187.73 lbs/hr of CO and H 2 , i.e., basic components of Syngas. The total Syngas production is 362 lbs/hr (97 SCFM).
[0041] Although the reduction of the CO 2 was less than in Case 1, the amount of Syngas produced still provides a significant economic advantage. The reason that Case 1 had a greater reduction of CO 2 than Case 2 may be because the higher C/CO 2 ratio and O 2 /CO 2 ratio of Case 2, produces proportionately more in-situ CO 2 that likely ends up in the syngas and consequently lowers the overall CO 2 conversion rate combined with the higher H 2 O/CO 2 more CO 2 may have been created in the syngas due to a water-gas shift reaction: CO+H 2 O⇄CO 2 +H 2 as is indicated by less H 2 O, less CO and more H 2 in the syngas.
[0000]
TABLE 7
(Case 3)
OUTPUT FROM
GASIFIER
INPUTS
1900° F. (1038° C.)
TO GASIFIER
and 14.696 psia
COMPONENT
(SCFM)
(lb/hr)
(Vol %)
(lbs/hr)
Shroud CO 2
15.09
104.75
Torch Air
29.0
132.24
(Approximately
30.55 lbs/hr O 2 &
99.87 lbs/hr N 2 & Ar)
Nitrogen purge
5.0
21.95
Coke, 70 lb/hr total
63.70
at 91.0% Carbon
H 2 O (steam)
23.00
SYNGAS OUTPUT
Carbon monoxide (CO)
39.28
160.9
Carbon dioxide (CO 2 )
7.54
48.53
Hydrogen (H 2 )
20.49
5.99
Ar
0.10
0.58
Nitrogen (N 2 )
30.65
125.55
Oxygen (O 2 )
0.02
0.09
H 2 O
1.50
3.95
TOTAL (approximately)
346
346
(352
(352
including
including
other output)
other output)
OTHER OUTPUTS:
Approximate output from bottom of
Gasifier: 6.27 lbs/hr Slag/Vitrified slag
Note:
166.89 lbs/hr of usable syngas (CO and H 2 ) and about 6.27 lbs/hr Slag/Vitrified slag was produced.
Note:
The feed ratio of carbon to CO 2 is 0.608 lbs/lb, and the feed ratio of Steam (H 2 O) to CO 2 is 0.220 lbs/lb. The feed ratio of total oxygen O 2 to CO 2 is 0.292 lbs/lb.
Note:
Water in = 23.00 lbs/hr or 1.27670 lbs-mole/hr; Carbon in = 63.70 lbs/hr or 5.3035 lbs-mole/hr; and Water out = 3.95 lbs/hr or 0.2188 lbs-mole/hr. Such that % Water consumed/carbon in × 100 = [(1.27670 − 0.2188)/5.3035] × 100 = 19.9%
[0042] In this test, the CO 2 conversion rate was 56.6% (includes CO 2 generated in-situ of 7.0 lbs/hr). However, the gasification temperature of 1900° F. was below the target temperature of 2426° F. because the plasma heat torch did not have the power to supply the desired energy to bring the chamber to the target temperature of 2426° F. This gasification temperature was 50° F. less than the temperature of Case 1 shown in Table 5. Also, as in Case 1 and 2, this test run used a coke bed in the reactor that was depleted at a rate of six inches per hour, which translates to 70 lbs/hr.
[0043] Thus, as set out above, it is seen that at the completion of the process the carbon dioxide (CO 2 ) has been reduced by about 56.6%. Also as was true in the previous two cases, the input mass to the reactor must, of course, equal the mass output from the reactor. The mass inputs and outputs of the reaction chamber shown in Table 7 are equal. Specifically, the total lbs/hr input equals approximately 346 lbs/hr and the total mass output also equals approximately 346 lbs/hr.
[0044] Although the reduction of the CO 2 for this Case 3 was less than in Case 1, but better than Case 2, the amount of Syngas produced (166.89 lbs/hr) was still less than Case 2. However, the amount of syngas produced in Case 3 still provides a significant economic advantage. In addition to the reduction of CO 2 , the process produces 166.89 lbs/hr of CO and H 2 , i.e., basic components of Syngas. The total Syngas production is 346 lbs/hr (93 SCFM).
[0045] The reason that this Case 3 had a greater reduction of CO 2 than Case 2 even though the amount of CO 2 lbs/hr is about the same in both Cases, may be because a lower H 2 O (Steam)/CO 2 created less CO in the syngas as is indicated by the less CO and H 2 in the syngas as a result of the lower water feed in Case 3. Also, since the rate of water consumed with respect to the carbon consumed (i.e., 19.9%), the shortage of water results in less CO and H 2 being created via the reaction C+H 2 O CO+H 2 because whatever water is available preferentially converts available CO to CO 2 via the water-gas shift reaction, i.e., CO+H 2 O CO 2 +H 2 .
[0000]
TABLE 8
(Case 0)
OUTPUT FROM
GASIFIER
INPUTS
2150° F. (1177° C.)
TO GASIFIER
and 14.696 psia
COMPONENT
(SCFM)
(lb/hr)
(Vol %)
(lbs/hr)
Shroud CO 2
19.95
138.49
Torch Air
28.97
132.1
(Approximately
30.52 lbs/hr O 2 &
99.76 lbs/hr N 2 & Ar)
Nitrogen purge
5.0
21.95
Coke, 70 lb/hr total
63.70
at 91.0% Carbon
H 2 O (steam)
0.00
SYNGAS OUTPUT
Carbon monoxide (CO)
40.53
154.1
Carbon dioxide (CO 2 )
8.64
51.63
Hydrogen (H 2 )
11.34
3.08
Ar
0.10
0.54
Nitrogen (N 2 )
37.63
143.1
Oxygen (O 2 )
0.02
0.08
H 2 O
1.50
3.67
TOTAL (approximately)
356
356
(362
(362
including
including
other output)
other output)
OTHER OUTPUTS:
Approximate output from bottom of
Gasifier: 6.27 lbs/hr Slag/Vitrified slag
Note:
157.18 lbs/hr of usable syngas (CO and H 2 ) and about 6.27 lbs/hr Slag/Vitrified slag was produced
Note:
The feed ratio of carbon to CO 2 is 0.460 lbs/lbs, and the feed ratio of Steam (H 2 O) to CO 2 is 0.000 lbs/lbs The feed ratio of total oxygen O 2 to CO 2 is 0.220 lbs/lbs
Note:
Water in = 0.00 lbs/hr or 0.00 lbs-mole/hr; Carbon in = 63.7 lbs/hr or 5.3035 lbs-mole/hr; and Water out = 3.67 lbs/hr or 0.2037 lbs-mole/hr Such that % Water consumed/carbon in × 100 = [(0.00 − 0.2037)/5.3035] × 100 = −3.84%. That means that water is being produced.
[0046] In this Case 0, the CO 2 conversion rate was 64.5% (includes CO 2 generated in-situ of 7.0 lbs/hr) which is almost the same as in Case 1 (64.0%). However, since the feed ratios of Case 1 and Case 0 are almost the same, with the exception of the H 2 O(steam)/CO 2 ratio, it is likely that a similar amount of in-situ CO 2 is created in the syngas of each. However, with no steam feed in Case 0, the energy supply from heat by the Plasma torch allows the temperature to reach 2,150° F. compared to only 1,950° F. for Case 1. Even so, the lower water feed to the Chamber in this Case 0 results in both lower CO and H 2 in the syngas. Consequently, it is seen that water/steam in the feed promotes a syngas of higher quality (i.e. more CO and H 2 ). This higher quality is believed to be a result of the reaction CO+H 2 O→CO 2 and H 2 ; and the reaction C+H 2 O→CO+H 2 . The decrease in the quantity of syngas produced as well as the lower quality of syngas (i.e. less CO and H 2 ) in Case 0 is believed to be because less water (H 2 O) is formed by the reaction H 2 +½O 2 and consequently less CO and H 2 formed via the C+H 2 O→CO+H 2 reaction. In addition, the water gas-shift reaction may affect H 2 production via CO+H 2 O→CO 2 +H 2 . It should also be noted that coke contains Hydrogen that may potentially form water. The lower production of H 2 and CO in Case 0 is likely due to insufficient amounts of water in the feed material. Also, as in cases 1-3, to provide the carbon, a coke bed in the reactor was depleted at a rate of six inches per hour, which translates to 70 lbs/hr.
[0047] Data from additional experimental test runs that took place at a later date and that also used equipment substantially as shown in FIG. 2 is set out in Tables 9-1 and 9-2 below. The equipment used in these test runs was similar to the test runs of Tables 5-8, but used a higher powered torch, i.e., a Marc 11 L torch.
[0000]
TABLE 9-1
INPUT
DESCRIPTION
RUN 1
RUN 2
RUN 3
RUN 4
RUN 5
RUN 6
RUN 7
RUN 8
RUN 9
Mass Ratios
O 2 /C0 2 ( * )
0.459
0.392
0.346
0.281
0.292
0.418
0.255
0.279
0.455
C/CO 2
0.672
0.586
0.432
0.475
0.420
0.592
0.441
0.549
0.493
Steam/CO 2
0.307
0.396
0.393
0.393
0.223
0.224
0.261
0.260
0.392
Steam/C
0.457
0.677
0.910
0.827
0.529
0.378
0.591
0.473
0.795
Temp. ° F.
1,953
1,835
1,886
1,631
1,632
1,719
1,553
1,733
2,018
Torch Power in kWe to reach
554
546
484
404
411
468
424
470
460
Temp.
INPUTS
Torch Air (lbs/hr)
329
329
292
238
238
338
338
370
370
Torch Air Composition
Torch N 2 (lbs/hr)
248.5
248.5
220.5
179.7
179.7
255.26
255.26
279.42
279.42
Torch O 2 (lbs/hr)
76.0
76.0
67.5
54.97
54.97
78.08
78.08
85.47
85.47
Torch Ar (lbs/hr)
4.24
4.24
3.77
3.08
3.08
4.36
4.36
4.77
4.77
% Torch N 2 wt. %)
75.52%
75.52%
75.52%
75.52%
75.52%
75.52%
75.52%
75.52%
75.52%
% Torch O 2 wt. %)
23.10%
23.10%
23.10%
23.10%
23.10%
23.10%
23.10%
23.10%
23.10%
% Torch Ar wt. %)
1.29%
1.29%
1.29%
1.29%
1.29%
1.29%
1.29%
1.29%
1.29%
Coke (lbs/hr)
135
137
102
112
96
134
163
204
112
Carbon (83% Wt. %)
112.1
113.7
84.66
92.96
79.68
111.2
135.3
169.3
92.96
Shroud CO 2 (lbs/hr)
154.44
182.52
182.52
182.52
175.5
175.5
294.84
294.84
175.5
Generated CO 2 (lbs/hr)
11.63
11.63
13.30
13.15
13.15
11.96
11.96
13.09
13.09
Shroud N 2 (lbs/hr)
368
368
368
302
302
302
302
302
0
Steam (lbs/hr)
51
77
77
77
42
42
80
80
74
( * ) Free Oxygen was introduced into the chamber via the plasma torch air.
[0000]
TABLE 9-2
OUTPUT
RUN 1
RUN 2
RUN 3
RUN 4
RUN 5
RUN 6
RUN 7
RUN 8
RUN 9
Gas
Composition
CO (Vol. %)
30.30%
29.92%
24.23%
28.75%
25.74%
28.44%
34.88%
38.62%
35.40%
CO 2 (Vol. %)
3.68%
3.50%
4.65%
5.98%
8.61%
7.99%
6.70%
6.05%
7.05%
H 2 (Vol. %)
5.81%
7.97%
6.66%
7.98%
4.80%
4.85%
7.07%
6.63%
6.57%
N 2 (Vol. %)
56.48%
53.38%
55.16%
52.15%
57.06%
56.22%
47.15%
44.98%
40.44%
H 2 O (Vol. %)
1.70%
2.50%
4.70%
4.60%
3.00%
2.00%
3.30%
3.20%
8.60%
O 2 (Vol. %)
2.03%
2.74%
4.61%
0.53%
0.78%
0.50%
0.90%
0.51%
1.94%
TOTAL (Vol. %)
100%
100%
100%
100%
100%
100%
100%
100%
100%
CO (Wt. %)
31.43%
31.80%
25.38%
30.44%
25.87%
28.60%
36.25%
40.14%
37.21%
CO 2 (Wt. %)
5.99%
5.84%
7.66%
9.95%
13.60%
12.63%
10.95%
9.88%
11.65%
H 2 (Wt. %)
0.43%
0.60%
0.50%
0.60%
0.34%
0.35%
0.52%
0.49%
0.49%
N 2 (Wt. %)
58.60%
56.72%
57.78%
55.22%
57.35%
56.55%
49.00%
46.74%
42.51%
H 2 O (Wt. %)
1.13%
1.71%
3.17%
3.13%
1.94%
1.29%
2.21%
2.14%
5.81%
O 2 (Wt. %)
2.41%
3.33%
5.52%
0.65%
0.90%
0.57%
1.07%
0.61%
2.33%
TOTAL (Wt. %)
100%
100%
100%
100%
100%
100%
100%
100%
100%
CO (lbs/hr)
325.94
347.74
259.36
277.51
220.69
283.67
427.20
502.21
272.31
CO 2 (lbs/hr)
62.16
63.87
78.26
90.72
115.98
125.30
128.99
123.60
85.26
H 2 (lbs/hr)
4.46
6.61
5.09
5.50
2.94
3.46
6.18
6.16
3.61
N 2 (lbs/hr)
607.68
620.36
590.44
503.40
489.14
560.79
577.48
584.88
311.08
H 2 O (lbs/hr)
11.76
18.68
32.34
28.54
16.53
12.83
25.99
26.75
42.53
O 2 (lbs/hr)
25.01
36.36
56.38
5.90
7.68
5.70
12.59
7.65
17.02
TOTAL (lbs/hr)
1,037.01
1,093.63
1,021.88
911.57
852.96
991.74
1,178.43
1,251.24
731.81
Total CO 2 In
166.07
194.31
195.95
195.78
188.76
187.61
306.95
308.10
188.76
(lbs/hr)
CO 2 Out
62.16
63.87
78.26
90.72
115.98
125.30
128.99
123.60
85.26
(lbs/hr)
% CO 2
62.60%
67.13%
60.06%
53.66%
38.56%
33.21%
57.98%
59.88%
54.83%
Reduction
Note:
No slag was recovered from these tests. The only potential for slag would be ash from the coke, in which case there was very little.
[0048] The effect on CO 2 reduction by four (4) input variables determined from the data in Tables 9-1 and 9-2, is discussed in more detail and illustrated in Tables 10-13. The four input variables were the C/CO 2 ratio, the H 2 O (Steam)/CO 2 ratio, the O 2 /CO 2 ratio and the chamber exit temperature were analyzed, and a predictive equation (Equation (6) shown below) illustrating the effect of the four input variables on the CO 2 reduction was developed by statistical analysis from data in Tables 9-1 and 9-2 above.
[0000] CO 2 Reduction=0.19145−0.07949×C/CO 2 +0.04844×H 2 O/CO 2 −0.34342×O2/CO2+0.00115×TorchPower Equation (6)
where, CO/CO2, H2O/CO2 and O2/CO2 are mass ratios, Torch Power is input (KW), and % CO 2 Reduction ═CO 2 Reduction×100
[0050] Based on the Predictive Equation (6), the curves of FIG. 3 compare the effect of the four input variables on the amount of CO 2 reduction. As shown, the greater the slope of the curve, the greater a change in the variable will have on the amount of CO 2 reduction. As shown, the curve with the greater change shows the CO 2 reduction as a function of Temperature. However, the Predictive Equation (6) was developed with respect to Torch Power. Although, there is not a strict linear relationship between torch power and the chamber or exhaust temperature, it will be appreciated by those skilled in the art, that the torch power is directly related to the temperature. It is also noted that the negative effect of the presence of free O 2 in the chamber, as was discussed above, is clearly illustrated.
[0051] In addition, second order curves shown in FIGS. 4-7 were prepared with the data from Tables 9-1 and 9-2, and represent the reduction of CO 2 as a function of the four variables (i.e., the C/CO 2 ratio, the H 2 O/CO 2 ratio, the O 2 /CO 2 ratio, and the temperature, respectively. The shaded areas of each curve reflect the range of data actually measured during the tests, and the portions of the curves outside the shaded areas represent an estimated extension of each of the second order curves.
[0052] As mentioned above, FIG. 2 is representative of the equipment used in the test runs that resulted in Tables 9-1 and 9-2 which show the different inputs for each test run. A Carbon source was provided during the tests to maintain the carbon bed or layer in the reactor at a constant level. To accomplish this, the carbon source provided carbon to the reactor at the same rate it was used or consumed during the reaction. Thus, the carbon feed rate also represents the carbon consumption rate. Also, of course, the different inputs for each test results in different outputs. Four of the more significant test runs are identified as Tables 10-13 below and represent Runs 1, 2, 7 and 8. The inputs and the resulting outputs from these test runs (Tables 9-1 and 9-2) are isolated and set out below in Tables 10-13. As was true with the earlier actual test run Cases 1-4/(0), although there is a bed of carbon that remains in the reaction chamber, there was no measurable amount of unreacted carbon (C) discharged in the exhaust or syngas.
[0053] In addition, to further aid in understanding the invention, four curves showing the ratio of input carbon to the total carbon dioxide (C/CO 2 ), input steam to total carbon dioxide (H 2 O/CO 2 ) and total oxygen to total carbon dioxide (O 2 /CO 2 ) for all nine runs are illustrated with the resulting percent CO 2 reduction (expressed as a fraction) of carbon dioxide (i.e., CO 2 out/CO 2 in) in FIG. 8 .
[0054] In addition, and although there is clearly a correlation, it should be noted from FIG. 8 , that the conditions that result in the greatest reduction in CO 2 does not necessarily generate the most syngas. Therefore, FIG. 9 illustrates on the same graph the reduction percentage of CO 2 and the amount of syngas (CO lbs/hr and H 2 lbs/hr) produced for each of the nine runs so that the effect of the input parameters can be evaluated for the maximum CO 2 reduction and the maximum syngas out.
[0000]
TABLE 10
(Run 1)
CHAMBER CONDITIONS 1953° F. (1067.2° C.) AND 14.696 PSI
Input To
Output From
Chamber
Chamber
COMPONENT
(Lbs/Hr)
(Lbs/Hr)
Total Input CO 2 from Shroud; Total Output
154.44
62.16
CO 2 from Syngas
Input Carbon (C) (Coke at 83% Carbon)
135 (111.7)
—
H 2 O
51.00
11.76
Total Nitrogen (N 2 ) Input & Output
616.5
607.68
(Input N 2 = Shroud + Torch)
Oxygen O 2 (From Torch)
76.0
25.01
Syngas Out
Carbon Monoxide (CO)
—
325.94
Hydrogen (H 2 )
—
4.46
TOTALS (note, no slag was recovered
1033.
1037.
from the output)
RATIOS: C/CO 2 = 0.672;
H 2 O/CO 2 = 0.307;
O 2 /CO 2 = 0.459 62.6% reduction
Note, the mass balance of input and output agree by 99.6%.
[0000]
TABLE 11
(Run 2)
Reactor Conditions 1835° F. (1001.7° C.) and 14.696 psi
Input To
Output From
Chamber
Chamber
COMPONENT
(Lbs/Hr)
(Lbs/Hr)
Total Input CO 2 from Shroud; Total Output
182.52
63.87
from Syngas
Input Carbon (C) (Coke at 83% Carbon)
137 (113.7)
0.00
H 2 O
77
18.68
Total Nitrogen (N 2 ) Input & Output
616.5
620.36
(Input N 2 = Shroud + Torch)
Oxygen O 2 (From Torch)
76
36.36
Syngas Out
Carbon Monoxide (CO)
—
347.74
Hydrogen (H 2 )
—
6.61
TOTALS (note, no slag was recovered
1089
1094
from the output)
RATIOS: C/CO 2 = 0.586;
H 2 O/CO 2 = 0.396;
O 2 /CO 2 = 0.392 67.1% reduction
Note, the mass balance of input and output agree by 99.5%.
[0000]
TABLE 12
(Run 7)
CHAMBER CONDITIONS 1553° F. (845.0° C.) AND 14.696 PSI
Input To
Output From
Chamber
Chamber
COMPONENT
(Lbs/Hr)
(Lbs/Hr)
Total Input CO 2 from Shroud; Total Output
294.84
128.99
CO 2 from Syngas
Input Carbon (C) (Coke at 83% Carbon)
163 (135.30)
—
H 2 O
80.00
25.99
Total Nitrogen (N 2 ) Input & Output
557.3
577.48
(Input N 2 = Shroud + Torch)
Oxygen O 2 (From Torch)
78.08
12.59
Syngas
Carbon Monoxide (CO)
—
427.20
Hydrogen (H 2 )
—
6.18
TOTALS (note, no slag was recovered from
1173
1178
the output)
RATIOS: C/CO 2 = 0.441;
H 2 O/CO 2 = 0.261;
O 2 /CO 2 = 0.255 57.98% reduction
Note, the mass balance of input and output agree by 99.6%.
[0000]
TABLE 13
(Run 8)
CHAMBER CONDITIONS 1733° F. (945.0° C.) AND 14.696 PSI
Input To
Output From
Chamber
Chamber
COMPONENT
(Lbs/Hr)
(Lbs/Hr)
Total Input CO 2 from Shroud; Total Output
294.84
123.6
CO 2 from Syngas
Input Carbon (C) (Coke at 83% Carbon)
204 (169.3)
—
H 2 O
80.00
26.75
Total Nitrogen (N 2 ) Input & Output
581.4
584.88
(Input N 2 = Shroud + Torch)
Oxygen O 2 (Input is from Torch)
85.47
7.65
Syngas Out
Carbon Monoxide (CO)
—
502.21
Hydrogen (H 2 )
—
6.16
TOTALS (note, no slag was recovered from
1246
1251
the output)
RATIOS: C/CO 2 = 0.549;
H 2 O/CO 2 = 0.260;
O 2 /CO 2 = 0.279 59.88% reduction
Note, the mass balance of input and output agree by 99.6%.
[0055] Therefore, by reviewing the computer simulated test runs and the fourteen actual test runs that validated the computer test runs, it can be predicted from the data obtained from these test runs that the preferred reaction temperature should be no lower than about 1500° F. (815.6° C.). It is also noted, that a temperature of about 2426° F. (1330° C.) was set as a target to achieve maximum CO 2 conversion, however, temperatures above 2426° F. (1330° C.) will also result in high CO 2 conversion, but may not provide any significant additional benefit.
[0056] To date, it has not been possible to operate present available test facilities at a temperature above 2150° F. However, the computer simulation tests clearly indicate, as discussed below, that if a higher temperature was to be used, the CO 2 reduction may well be increased to a level even better than the actual 67.13% achieved during one of the last nine test runs and without measurable uncombined carbon in the syngas output. However, a temperature below about 1500° F. (815.6° C.) may result in some unreacted carbon material in the carbon bed being exhausted such that unreacted carbon (C) could be present in the exhaust and/or syngas. Such unreacted carbon could also leave deposits on the chamber walls and possibly deactivate a catalyst if one were used.
[0057] The data results of the nine test runs verified that using temperatures between 1553° F. and 2018° F. for the inventive process provides a CO 2 reduction of between 33.21% and 67.13% when the ratio of C to CO 2 was maintained between about 0.420 and 0.670, the ratio of steam (H 2 O) to CO 2 was maintained between about 0.220 and 0.400; and the O 2 to CO 2 ratio was maintained between about 0.2 and 0.5. Further, and referring to Runs 7 and 8, it can be seen that although the total reduction of CO 2 was not as great as in Runs 1 and 2, the amount of commercially usable syngas (CO and H 2 ) produced was significantly higher (i.e. 433.38 lbs/hr and 508.37 lbs/hr respectively.
[0058] In addition, by extrapolating from the second order curves of FIGS. 4-7 and/or using the Predictive equation (6) above, it can also be predicted that satisfactory CO 2 reduction should also result at a C/CO 2 ratio of between about 0.200 and 0.900, a H 2 O/CO 2 ratio of between about 0.100 and 0.500, and the O 2 /CO 2 ratio should preferably be less than 0.600. In addition, it is believed, and the predictive equation confirms, that use of a chamber that can maintain temperatures of 2426° F. (1330° C.) and higher during the process, reduction rates of 90% or greater can be achieved.
[0059] As will be appreciated by those skilled in the art, other known ecologically friendly processes can be combined with the inventive process described above. As an example and referring to FIG. 10 , there is shown the process of, FIG. 1 wherein the source 22 for creating heat energy (i.e., electricity, steam, etc. is the syngas from gasification chamber 36 produced by a prior art plasma arc carbonaceous material gasification process that uses various waste products such as municipal solid waste (MSW) as a fuel source to produce the syngas. It should also be clearly understood, that the gasification chamber 36 discussed with the embodiment of FIG. 10 operates at a significantly lower temperature than the reaction chambers 10 discussed above with respect to this invention, and does not reduce a CO 2 stream to produce syngas. That is, the gasification chamber 36 does not convert carbon dioxide to syngas. Only the reactor 10 in FIG. 1 represents the reaction chamber of this invention. As shown, in FIG. 10 , the MSW (municipal Solid Waste) 34 is provided to the plasma arc Gasifier 36 along with an oxygen source 38 . Other carbon materials, such as coke could be used as. In any event, the Gasifier 36 converts the input coal, coke or other carbonaceous material (not CO 2 ) to a dirty or raw syngas and provides this syngas as indicated by line 40 a as an output. Other byproducts 42 include metals and vitrified slag. The dirty syngas is then provided to an emission control system 45 to remove various other byproducts 46 from the syngas such as sulfur and hydrochloric acid, etc. This leaves a clean syngas provided on line 40 b that is then used to provide the required energy to produce the necessary steam and heat energy used by the pyrolysis reaction chamber to reduce the input stream of carbon dioxide and convert it to syngas according to the teachings of this invention.
[0060] Referring now to FIG. 11 , there is again shown the process of FIGS. 1 and 2 . However, as shown, the syngas generated according to the teachings of this invention is now further processed to produce ethanol. As shown, the syngas 32 is provided by line 50 to a water-gas shift reactor 52 and then to a bio-catalytic or catalytic reactor 54 such as a Fischer-Tropsch synthesis reactor. As known by those skilled in the art, the Fischer-Tropsch reactor may be used to convert the syngas 32 to Ethanol as indicated by block 56 . More specifically, for a bio-catalytic reactor assuming that a flow of Syngas comprised of about 156,147 lbs/hr of carbon monoxide (CO), 2,545 lbs/hr of hydrogen (H 2 ), 75,195 lbs/hr of carbon dioxide (CO 2 ) is provided to the water-gas shift reactor 52 , water (steam) will be required to adjust the carbon monoxide (CO) and hydrogen (H 2 ) molar ratio to 3.00 moles of carbon monoxide (CO) for 1.00 each mole of hydrogen (H 2 ).
[0061] This adjustment is according to the reaction represented by:
[0000] CO+H 2 O→CO 2 +H 2 . Equation (5):
[0062] Thus, it will be appreciated that the water-gas shift reactor 52 can be adjusted to produce Syngas having a wide range of molar ratios to meet the needs of various conversion processes that convert or use Syngas. Conversion processes presently in use may successfully operate with carbon monoxide (CO) to hydrogen (H 2 ) ratios that range between 0.2 to 5.0 moles of carbon monoxide and 5.0 to 0.2 moles of hydrogen.
[0063] More specifically, a mass flow rate of 156,147 lbs/hr of carbon monoxide (CO) is 5,574.7 lbs-mole/hr, and 2,545 lbs/hr of hydrogen (H 2 ) is 1,262.4 lbs-mole/hr of hydrogen (H 2 ). Therefore, the water-gas shift reactor is set to shift or rearrange the amount of carbon monoxide (CO) and hydrogen (H 2 ) such that the final mixture ratio comprises 5,127.8 lbs-mole/hr of carbon monoxide (CO) and 1,709.3 lbs-mole/hr of hydrogen (H 2 ). This shift is selected to facilitate the reaction that produces Ethanol (C 2 H 5 OH). The reaction is shown below in Equation (7).
[0000] CO+H 2 +H 2 O→C 2 H 5 OH Equation (7)
[0064] Similar to the above discussion concerning Equation (5), this reaction takes place with a carbon monoxide (CO) to hydrogen (H 2 ) molar ratio of between 3.0 and 0.2 of Carbon Monoxide to 1.0 of hydrogen. With this adjustment, the production of Ethanol from a bio-catalytic reactor is about 60,136 lbs/hr of Ethanol, which is about 80,120,000 gallons/yr. after distillation.
[0065] This reaction does not produce carbon dioxide (CO 2 ). Therefore, from the start of the industrial gaseous stream 14 containing 160,000 lbs/hr of carbon dioxide (CO 2 ) to the discharge of the pyrolysis reactor 10 , the reduction in emitted carbon dioxide (CO 2 ) is 75,195 lbs/hr, or a reduction of about 53%. The water-gas shift adds about 19,667 lbs/hr of carbon dioxide (CO 2 ) for a total of 94,862 lbs/hr of carbon dioxide (CO 2 ) rather than the original 160,000 lbs/hr for about a total 40% reduction. Of course, in addition to the reduction in exhausted CO 2 , there is a bonus of 60,136 lbs/hr (or 80,120,000 gallons/yr.) of ethanol. It will be appreciated, of course, if the reduction of the CO 2 is at the higher rates (i.e., 67% to 90+%), as was discussed above, the overall reduction rate would be greater than the 40% illustrated.
[0066] Referring to FIGS. 12 , 12 a and 12 b , there is shown a more detailed block flow diagram for producing ethanol that uses two bio-catalytic reactors in series and which illustrates the flow rate of gases, steam, and carbonaceous materials, etc. The reference numbers of common elements or systems are the same as in FIG. 10 . However, as shown, rather than a single bio-catalytic converter 54 , there is a first bio-catalytic converter 54 a that results in the 80,114,836 gallons/yr. of Ethanol (block 56 ) after being distilled as indicated at 58 . As is also shown, however, the tail gas from the bio-catalytic converter 54 a comprises 94,862 lbs/hr of carbon dioxide (CO 2 ), as well as 21,714 lbs/hr of carbon monoxide (CO) and 1,897 lbs/hr of hydrogen (H 2 ) as indicated in block 60 . Therefore, according to this embodiment, the tail gas of block 60 is provided to a second bio-catalytic converter 54 b , that is assumed to operate at a 50% of the yield used in bio-catalytic reactor #1.
[0067] Another water-gas shift, as discussed above, is also indicated at block 52 . The output of the second bio-catalytic converter 54 b is another 6,055,899 gallons/yr. of ethanol, as indicated at block 64 , after passing the gas through a second distillation process 62 for a total of 86,170,735 gallons/yr. Since the process does not add carbon dioxide (CO 2 ), the tail gas indicated at block 66 from the second bio-catalystic converter 54 b still contains the 94,802 lbs/hr of carbon dioxide (CO 2 ) but reduced carbon monoxide (CO). However, even if the discharge of the tail gas from the second reactor is not recovered as a fuel, but is instead destroyed with a flare burn-off to the atmosphere, an additional 19,638 lbs/hr of carbon dioxide (CO 2 ) may be added to the 94,862 lbs/hr to give a remaining total of 114,500 lbs/hr of carbon dioxide (CO 2 ). However, this still represents a 28.4% reduction of carbon dioxide (CO 2 ) plus the bonus of 86,170,735 gallons/yr. of ethanol.
[0068] Referring again to FIG. 12 a and if a carbonaceous source contains some non-hydrocarbon impurities, the Syngas may then be provided to an emission control system 30 , as was also shown in FIGS. 1 and 10 , to remove impurities and clean up the syngas. Also as shown, the carbon dioxide (CO 2 ) in the syngas removed by the Emission Control System and syngas Cleanup processor 30 may be returned to the pyrolysis reactor, as indicated by dotted line 12 a . Depending upon the feed to the pyrolysis reactor, the impurities in the syngas could be about 0.5 wt. % chlorine and 0.8 wt. % sulfur based upon an elemental analysis of the feed, as an example. Most of the sulfur is converted to hydrogen sulfide (H 2 S) but some is converted to carbonyl sulfide (COS). Chlorine is converted to hydrogen chloride (HCl). Trace elements of mercury and arsenic can be found in the syngas prior to cleaning. Some particulate carryover may occur with the syngas from the pyrolysis reactor. Selection of the technology for gas cleanup depends upon the purity requirements of downstream processes using the syngas.
[0069] Particulate control is typically a Metal Candle filter or Water scrubber in combination with a cyclone. Sulfur recovery is typically of a Claus plant. The acid gases such as hydrogen chloride are recovered by solvent-based processes. Thus, syngas comprised of carbon monoxide (CO) and hydrogen (H 2 ) is available for further processing, as indicated at block 32 .
[0070] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
[0071] Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, means, methods, or steps. | A system and method for reducing the CO 2 in a gaseous stream between 33% up to and even in excess of 90%, by reducing CO 2 . A gaseous stream that includes substantial amounts of CO 2 is provided to a reaction chamber along with H 2 O (steam) and a carbon source such as charcoal, coke or other carbonaceous material. Carbon is provided to the chamber at a ratio (C/CO 2 ) of between about 0.100 to 0.850, and between about 0.200 to 0.900 of H 2 O to the provided CO 2 . The CO 2 , H 2 O and carbon are heated to between about 1500° F. and about 3000° F. at about one atmosphere to produce syngas (i.e. carbon monoxide (CO) and hydrogen (H 2 )) and reduces the amount of CO 2 . The Syngas may then be cleaned and provided to a Fischer-Tropsch synthesis reactor or a Bio-catalytic synthesis reactor to produce a fuel, such as Methanol, Ethanol, Diesel and Jet Fuel. | 2 |
This is a continuation of application Ser. No. 692,522 filed June 3, 1977 and now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a relatively small liquid sprayer suitable for distributing and spraying the liquid contained in a container.
There are many conventional sprayers of this type. In all the conventional sprayers, the liquid sucked into a cylinder is sprayed by increasing the pressure inside the cylinder through the depressing operation of a piston and therefore the internal pressure of the cylinder varies with the depressing speed of the piston. As a result, the condition of atomized liquid affected by the internal pressure of the cylinder is inevitably varied with the depressing speed of the piston. Therefore, when the piston speed is high, a good quality spray is generated, but when it is low, atomization is not good. When piston speed is further lowered, the liquid is not atomized but is ejected in a solid non-atomized jet, without achieving the prime object of a sprayer. Even when the depressing speed of the piston is high, the internal pressure of the cylinder is lowered when spraying of the liquid sucked in the cylinder is nearly completed, and therefore the liquid is discharged in the form of a jet or droplets from the nozzle, resulting in deterioration of the liquid cut-out performance. This phenomenon will cause not only non-uniformity of the liquid sprayed, but also a poor or dirty appearance of a sprayed surface due to stains, etc.
This invention contemplates overcoming the aforementioned disadvantages of the conventional liquid sprayer, and to provide a novel and improved liquid sprayer.
OBJECTS OF THE INVENTION
It is, therefore, an object of the present invention to provide a liquid sprayer which can always generate a good quality spray irrespective of the speed at which the piston is depressed.
It is another object of the present invention to provide a liquid sprayer which can maintain the pressure in the cylinder at a predetermined level irrespective of the speed of travel of the piston.
It is still another object of the present invention to provide a liquid sprayer which can always generate a good quality spray irrespective of the speed of travel of the piston.
It is yet another object of the present invention to provide a liquid sprayer which can maintain the pressure in the cylinder at a predetermined level irrespective of the speed of travel of the piston.
It is a further object of the present invention to provide a liquid sprayer which has a good liquid cut-out performance and is high in reliability.
It is a still further object of the present invention to provide a liquid sprayer which can be used in any position.
These and other objects, features and advantages of the present invention will become more fully apparent from the following description taken in conjunction with the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical cross-sectional view illustrating a first embodiment of a liquid spraying device constructed in accordance with the teachings of the present invention;
FIG. 2 is a fragmentary, enlarged vertical cross-sectional view of a limited portion of FIG. 1, with the discharge valve in closed condition;
FIG. 3 is a view taken on the line III--III of FIG. 2;
FIG. 4 is a vertical cross-sectional view generally similar to that of FIG. 1 but illustrating the device in operation;
FIG. 5 is a vertical cross-sectional view of another embodiment of the present invention in an inoperative state;
FIG. 6 is a vertical cross-sectional view of the embodiment of FIG. 5 showing the device in an operative state;
FIG. 7 is a further cross-sectional view of a third embodiment of the present invention in an inoperative state.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to the drawings, a liquid container 1 has a neck 2 to which a support member 3 is removably connected by a force-fit or screw-fit. The support member 3 has a cylinder 4 suspended therefrom and an external cylinder 4' extending upwardly. It also has a hole 5a at the center of the top wall 5 thereof. An actuator in the form of a cap 7 having a spray nozzle 6 at one side thereof is adapted to fit in the external cylinder 4'. A reciprocal means in the form of a movable valve 8 fitted in the actuator in the form of a cap 7 at its one end is adapted to be slidable in the cylinder 4 through the hole 5a of the support member 3. Thus a pressure chamber 9, which is defined by the movable valve 8 and the cylinder 4, is formed in the cylinder 4. In this manner, pressurized liquid spray means A is constituted.
The aforementioned movable valve 8 may be formed of synthetic resin integrally with a piston ring 8a or may be fitted in a piston ring separately formed of any other material. The bottom extension 10 of the cylinder 4, provides a suction chamber 10a for communication with the pressure chamber 9 and a suction tube 11 having a passageway 11a is associated with a passage 10b. The suction tube 11 is suspended from the passage 10b so that it may reach nearly to the bottom of the liquid container 1. In the pressure chamber 9, there is also provided a movable valve means in the form of an elongated rod 12 having an outer diameter smaller than the inner diameter of said movable valve 8 and having a valve element 13 at the top portion thereof. The lower portion of the valve rod extends into the suction chamber 10a. A compression spring 14 is disposed between the piston rod 12 and the bottom of the suction chamber 10a so that it may urge the movable valve rod 12 and the movable valve 8 upwardly to close a passage 15, all of which is clear from the view of FIG. 1.
The movable valve 8 and the movable valve rod 12 are disposed on the same axis so that they as a reciprocable means may be lowered by a piston-depressing-operation against the action of the compression spring 14 with the passage 15 of the movable valve 8 being closed. A ring-shaped elastic valve 16 (FIG. 2) is slidably fitted onto the movable valve rod 12. The elastic valve 16 is thus supported by the valve rod 12 so that it may reciprocate between an upwardly facing shoulder 17 (provided at the boundary portion 17a provided between the pressure chamber 9 and the suction chamber 10a) and a friction fitted annular control means 18 for said elastic valve means is seated in the aforementioned boundary portion. The control means 18 includes a perforation 19 through which the movable valve rod 12 is arranged to slide and, in addition, also provides a recess 20 between the upper portion thereof and the shoulder 17. A plurality of passages 21 (FIG. 3) are radially disposed on a downwardly facing shoulder portion of control means 18 and thereby provide for communication between the perforation 19 and the recess 20. The elastic valve 16 is thus moved upwardly and downwardly by the vertical movement of the valve rod 12 betwen the upwardly facing shoulder 17 and the downwardly facing shoulder of the recess 20. When the elastic valve 16 is moved downwardly to engage with the upwardly facing shoulder 17, a communication between the pressure chamber 9 and the suction chamber 10 is shut off. When the elastic valve 16 is moved upwardly, communication between the pressure chamber 9 and the suction chamber 10 is ensured through the passages 21. In this way, check valve means C is constituted as is best shown in greater detail in FIGS. 2 and 3.
Accordingly from the foregoing description, it will be observed that in the first embodiment shown in FIGS. 1 to 4, the movable valve 8 has a large-diameter portion into which the upper portion of the movable valve rod 12 is arranged to extend, and the compression spring 14 is disposed in the lower cavity in rod 12 between wall 12C and the bottom of suction chamber 10.
As distinguished therefrom, the second embodiment shown in FIGS. 5 and 6, shows the movable valve rod 12 is further provided adjacent to its upper portion with an annular flange 23 and the compression spring 14 surrounds the valve rod 12 and extends between the lower surface of the flange 23 and the control means 18.
In the third embodiment shown in FIG. 7, the movable valve rod 12 is provided adjacent to its upper portion with an elongated aperture 26 into which is inserted an extension element 12a with the extension being retained in the aperture 26 by convergent fingers 27. The extension element 12a has a dependent guide rod 25 provided at its terminus with portion 24 and is retained in the aperture 26 by the convergent fingers 27. Of course, it will be understood that the guide rod may be formed on the lower member and the tubular portion may be formed on the upper member. Thus the movable valve rod 12 is adapted to expand and contract within a predetermined range. As will be described later in greater detail, when the movable valve rod 12 is lowered by the action of the inside pressure of the pressure chamber 9, the lower member 12b is first lowered thereby causing the enlarged portion 24 to contact convergent fingers 27 and then the upper member 12a is caused to move downwardly together with the lower member 12b to thereby open the passage 15 of the movable valve 8. In this way, the movable valve rod 12 is adapted to be operated in two stages and, in addition, can achieve the same function and effect as those of the first and second embodiments.
Throughout the views, the reference numeral 28 designates air grooves longitudinally provided on the peripheral wall of the movable valve rod 12. When the piston 8 is at its lowermost position in the initial stage of spraying operation, (See FIG. 6) the air grooves 28 lets the pressure chamber 9 communicate with the suction chamber 10 to exhaust the air contained in the pressure chamber 9 into the liquid container 1 thereby ensuring downward movement of the movable valve 8, and suction of liquid into the pressure chamber 9. The reference numeral 29 (FIGS. 4-7) designates an air inlet provided at one side of the upper portion of the peripheral wall of the cylinder 4. The air inlet 29 prevents reduction of the pressure in the liquid container 1 when the liquid in the container 1 is sprayed.
The operation of the liquid sprayer according to the present invention will now be described.
In FIGS. 1, 5 and 7, each of which shows the inoperative condition of each embodiment, the movable valve 8 is lifted up by the movable valve rod 12 by the action of the compression spring 14 to thereby close the passage 15, and the elastic valve 16 is also at its uppermost position with the result that no liquid is sucked into the pressure chamber 9.
If the movable valve 8 is depressed from the above-mentioned position, the movable valve rod 12 is lowered with the passage 15 of the movable valve 8 being closed and when the air grooves 28 reach the position where they can make communication between the pressure chamber 9 and the suction chamber 10a, the air contained in the pressure chamber 9 is exhausted into the liquid container 1. Thereafter, if the depressing force applied on the movable valve 8 is removed, the movable valve rod 12 and the movable valve 8 is moved upwardly, and the elastic valve 16 is also moved upwardly to abut against the downwardly facing shoulder 18 where it stops. In this state, liquid is sucked from the container 1 into the pressure chamber 9 through the suction tube 11, suction chamber 10 and the passages 21. Accordingly, if the movable valve 8 is again depressed, the movable valve rod is lowered in the same manner as mentioned above and, therefore, the elastic valve 16 abuts against the upwardly facing shoulder 17 to shut off communication between the pressure chamber 9 and the suction chamber 10. Thus the downward movement of the movable valve 8 results in increase of the internal pressure of the pressure chamber 9. When the internal pressure of the pressure chamber 9 is further increased in this manner to exceed the resilient force of the compression spring 14, the movable valve rod is lowered by the action of the internal pressure of the pressure chamber 9 and, therefore, the passage 15 of the movable valve 8 is opened to spray liquid through the nozzle 6 by the action of the internal pressure of the pressure chamber 9. As the spraying operation proceeds, the internal pressure of the pressure chamber 9 gradually decreases and, therefore, the movable valve rod 12 is lifted up to close the passage 15 thereby to suddenly stop the liquid spray.
As mentioned above, the movable valve rod 12, which opens and closes the passage 15, is provided with an elastic valve 16 slidably and closely fitted thereto and having an outer diameter smaller than the inner diameter of the cylinder 4. Therefore, the pressure chamber 9 can be pressurized by depressing the movable valve 8. In addition, it is not until the internal pressure of the pressure chamber 9 reaches a predetermined level that the movable valve rod 12 is lowered to open the passage 15 of the movable valve 8 thereby spraying liquid. Thus, liquid can be sprayed in the atomized state irrespective of the depressing speed of the movable valve 8. Moreover, since the decrease in the internal pressure of the pressure chamber 9 results in the upward movement of the movable valve rod 12 and thereby closes the passage 15 to stop spraying, the liquid spraying can be stopped in the atomized state without creating a solid non-atomized jet and the liquid cut-out performance is improved.
It will be understood from the foregoing description that the liquid sprayer according to the present invention can increase the internal pressure of the pressure chamber to a predetermined level irrespective of the piston depressing speed; can always obtain good atomized conditions of liquid for any kinds of piston depressing operations since the internal pressure of the pressure chamber, after it has reached a predetermined level, lowers the movable valve rod to open the passage of the movable valve; can eliminate the generation of a non-atomized jet of liquid since the movable valve rod closes the passage of the movable valve to stop spraying of liquid at its atomized state; can improve the liquid cut-out performance; can be used at any position including vertical, oblique and horizontal positions since the check valve means for establishing or cutting off communications between the pressure chamber and the suction chamber has an elastic valve closely fitted onto the movable valve rod and the passage of the movable valve is opened and closed directly by the movable valve rod as mentioned above. | A liquid sprayer having a cylinder with a pressure chamber and a suction chamber, a hollow piston with a liquid passage therethrough and slidably fitted in said cylinder, an actuator mounted on the piston, a suction tube suspended from the bottom of the suction chamber into a liquid container, a movable valve rod vertically movable provided in the piston and cylinder and having a valve portion at the top end thereof for opening and closing the liquid passage of the piston, a compression spring for at all times urging the movable valve rod towards the direction of lifting up the piston with the liquid passage thereof being closed, and an elastic valve closely and slidably fitted onto the valve rod and adapted to establish communication between the pressure chamber and the suction chamber at its uppermost position and cut off communication therebetween at its lowermost position; whereby the passage of the piston communicating with a spray nozzle is opened when the internal pressure of the pressure chamber exceeds a predetermined level. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a CMOS, and more particularly, to a power supply switching circuit.
In an LSI using an EPROM and the like, it is necessary to apply a potential which is higher than a power supply potential (V DD ) for writing while in the write mode, and to use the standard potential and a potential which is higher than the standard potential as power supplies and to switch them.
Heretofore, as a circuit for switching power supplies as described above, there is, for example, a power supply switching circuit shown in FIG. 4.
This conventional circuit includes a first p-channel MOS transistor P1 and a second p-channel MOS transistor P2 which are connected in series, and a high potential V PP is supplied from IN2 to the source of the first p-channel MOS transistor P1, and a standard potential (V DD ) is supplied from a terminal 10 to the drain of the second p-channel MOS transistor P2.
An input terminal IN1, to which control signals are input, is connected to the input of a level shifter 8, through which the gate of the first p-channel MOS transistor P1 is connected. The input terminal IN1 is also connected to the gate of an inverter circuit 7 which comprises a p-channel MOS transistor P4 and an n-channel MOS transistor N5.
An output terminal OUT1 is connected to a connection point of the drain of the first MOS transistor and the source of the second MOS transistor, and grounded at GND0 via the p-channel MOS transistor P4 and is the n-channel MOS transistor N5. The gate of the second MOS transistor P2 is connected to a connection point of the p-channel MOS transistor P4 and the n-channel MOS transistor N5.
Now, the operation of this power supply switching circuit of the prior art will be explained.
An input signal is applied to the input terminal IN2 at the potential level V PP which is higher than the standard potential (V DD ).
The level shifter 8 is inserted for completely turning off the first p-channel MOS transistor P1 when the level "V DD " is input to the input terminal IN1, and is a circuit which outputs the level IN2 when the level "V DD " is input to the input terminal IN1, and outputs the level "GND" when the level "GND" is input.
First, when the level "GND" is input to the input terminal IN1, the level "GND", which is an output of the level shifter 8, is applied to the gate of the first p-channel MOS transistor P1, and the first p-channel MOS transistor P1 is turned on. Accordingly, a connection point 6 (node) of the drain of the first MOS transistor P1 and the source of the second MOS transistor P2 comes to the level "V PP ".
Furthermore, since the level "GND" is applied to the qate of the n-channel MOS transistor N5 of the inverter 7 connected to the input terminal IN1, the n-channel MOS transistor N5 is turned off. The level "GND" is also applied to the gate of the p-channel MOS transistor P4 connected to the input terminal IN1, and since the node 6 is at the level "V PP ", the p-channel MOS transistor P4 is turned on. The gate of the secOnd MOS transistor P2 comes to the level "V PP " via the turned-on p-channel MOS transistor P4, and the second MOS transistor P2 is completely turned off. Consequently, the level "V PP " is output from the output terminal OUT1.
When the level "V DD " is input to the input terminal IN1, the level "V PP ", which is an output of the level shifter 8, is applied to the gate of the first p-channel MOS transistor P1, and the first p-channel MOS transistor P1 is turned off. Furthermore, since the level "V DD " is applied to the gate of the n-channel MOS transistor N5 of the inverter 7 connected to the input terminal IN1, the n-channel MOS transistor N5 is turned on. The gate of the second p-channel MOS transistor P2 then becomes at the level "GND", and the second p-channel MOS transistor P2 is turned on. Hence, the node 6 comes to the level "V DD ". Since the gate and the source of the p-Channel MOS transistor P4 are both at the level "V DD ", the p-channel MOS transistor P4 is turned off. Hence, the level "V DD " of the node 6 is output as it is from the output terminal OUT1.
As described above, in the power supply switching circuit of the prior art shown in FIG. 4, the level "V PP " is output when the level "GND" is input to the input terminal IN1, and the level "V DD " is output from the output terminal OUT1 when the level "V DD " is input to the input terminal IN1.
When a potential applied to the high-potential input terminal IN2 is at a level equivalent to or higher than the level "V DD ", no forward-direction bias is applied to a parasitic diode D1 which exists between a source diffusion region (p-type) and an n-well of the first p-channel MOS transistor P1 as shown in FIG. 5, and so no current flows.
However, when a potential applied from the input terminal IN2 is lower than the level "V DD ", although the first p-channel MOS transistor P1 is turned off, a forward-direction bias is applied to the parasitic diode D1 to conduct it. Hence, a current path is formed between the V DD and the IN2 via the first and second p-channel MOS transistors P1 and P2, and the output level from the output terminal OUT1 decreases.
Since there exists the above-described inconvenience when a potential applied from the input terminal IN2 is lower than the level "V DD ", a high-potential input signal and other input signals can not use the terminal IN2 in common, and it is necessary to provide exclusive terminals for respective inputs.
SUMMARY OF THE INVENTION
The present invention has been made on the basis of the above-described background. It is an object of the present invention to provide a power supply switching circuit in which an input terminal can be used in common for other input signals, in a semiconductor device, such as a CMOS.LSI and the like, having inputs of many potential levels.
After performing research and development for solving the above-described problems, the inventor has found that, by further providing a third MOS transistor between a first MOS transistor and an output terminal OUT, the third MOS transistor is turned off even when a potential applied from an input terminal is lower than the level "V DD ", a reverse bias is applied to a parasitic diode to suppress the above-described conduction and securely maintain an output level from the output terminal OUT without decreasing the level, and it is possible to use the input terminal in common for other input signals, and thus completed the present invention.
That is, a power supply switching circuit of the present invention is a power supply switching circuit comprising first and second MOS transistors which are connected in series, for outputting a power supply potential by switching using a standard potential and at least one kind of potential which is different from the standard potential.
The invention includes a third MOS transistor between the first and second MOS transistors. The source of the third MOS transistor is connected to the drain of the first MOS transistor, the drain of the third MOS transistor is connected to the source of the second MOS transistor, and the back gate of the third MOS transistor is connected to an output.
A connection point of the drain of the third MOS transistor and the source of the second MOS transistor is made an output.
A high potential or a low potential is supplied to the source of the first MOS transistor, and a standard potential is supplied to the drain of the second MOS transistor.
In a preferred aspect of the present invention, the first, second and third MOS transistors may be p-channel transistors, and a high potential may be supplied to the source of the first MOS transistor.
In the aspect of providing p-channel transistors and supplying a high potential to the source of the first MOS transistor, a gate signal of the second MOS transistor may be made an output signal of an inverter comprising MOS transistors in which an output is from a source.
Furthermore, in the aspect of providing p-channel transistors and supplying a high potential to the source of the first MOS transistor, a gate signal of the first MOS transistor may be supplied from a level shifter which outputs a high potential or a ground potential.
In another aspect of the present invention, the first, second and third MOS transistors may be n-channel transistors, and a low potential may be supplied to the source of the first MOS transistor.
The function of the power supply switching circuit according to the present invention will be schematically explained.
In the power supply switching circuit of the present invention, the third MOS transistor is newly provided between the first and second MOS transistors. That is, the third MOS transistor is provided between the first MOS transistor and the output terminal OUT. Hence, the third MOS transistor is turned off even when a potential applied from the input terminal is lower than the level "V DD " of the standard potential, and a reverse bias is applied to a parasitic diode which exists between a source diffusion region and an n-well of the third MOS transistor to suppress conduction between the standard potential and the input terminal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit configuration diagram showing an embodiment of a power supply switching circuit according to the present invention;
FIG. 2 is an explanatory diagram of the circuit shown in FIG. 1;
FIG. 3 is a circuit configuration diagram showing a modified example of a power supply switching circuit according to the present invention;
FIG. 4 is a circuit configuration diagram showing an example of a power supply switching circuit of the prior art; and
FIG. 5 is an explanatory diagram for explaining disadvantages of the circuit example shown in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be further explained with reference to the drawings.
FIG. 1 is a circuit configuration diagram of an embodiment according to the present invention, and FIG. 2 is a circuit configuration diagram for explaining the function of the circuit of the embodiment.
A power supply switching circuit of the embodiment comprises a first MOS transistor P1 and a second MOS transistor P2 which are connected in series, and a third MOS transistor P3 between the first and second MOS transistors P1 and P2. The drain of the first MOS transistor P1 is connected to the source of the third MOS transistor P3, the source of the second MOS transistor P2 is connected to the drain of the third MOS transistor P3, and the back gate of the third MOS transistor is connected to an output OUT1. A connection point 6 of the drain of the third MOS transistor P3 and the source of the second MOS transistor P2 is made to the output OUT1, a high potential V PP is supplied to the source of the first MOS transistor P1 as input IN2, and a standard potential V DD is supplied to the drain of the second MOS transistor P2.
Accordingly, the output OUT1 is connected to IN2 via the transistors P3 and P1, to a standard potential V DD 10 via the transistor P2, and also to GND0 via transistors P4 and N5 which constitute an inverter circuit 7.
On the other hand, an input terminal IN1 for control signals is connected to the input of a level shifter 8, to the gate of the third p-channel MOS transistor P3, and also to the gate of the inverter circuit comprising the transistors P4 and N5.
Furthermore, the gate of the first p-channel MOS transistor P1 is connected to the output of the level shifter 8, and the gate of the second p-channel MOS transistor P2 is connected to a connection point of the p-channel MOS transistor P4 and the n-channel MOS transistor N5.
The level shifter 8 is inserted for completely turning off the first p-channel MOS transistor P1 when the level "V DD " is input to the input terminal IN1, and is a circuit which outputs the level IN2 when the level "V DD is input to the input terminal IN1, and outputs the level "GND" when the level "GND" is input.
Next, the operation of the circuit of the embodiment according to the present invention will be explained.
When a potential "V PP " which is no lower than the level "V DD " is applied to the IN2, the operation is as follows.
First, when a potential of the level "GND" is applied to the IN1, the gates of the first p-channel MOS transistor and the third p-channel MOS transistor P3 both becomes at the level "GND", the both transistors are turned on, and the node 6 becomes at the "V PP ". At this time, since a potential of the level "GND" is applied to the gate of the n-channel MOS transistor N5, the transistor N5 is turned off. Since a potential of the level "GND" is also applied to the gate of the p-channel MOS transistor P4, and the node 6 is at the level "V PP ", the transistor P4 is turned on. The gate of the second p-channel MOS transistor P2 comes to the level "V PP ", and the transistor P2 is completely turned off. Hence, the level "V PP " is output at the output terminal OUT1.
Next, when the level "V DD " is applied to the IN1, the gate of the first p-channel MOS transistor P1 comes to the level "V PP ", and the transistor P1 is turned off. Since the gate of the n-channel MOS transistor N5 comes to the level "V DD ", the transistor N5 is turned on, and since the gate of the second p-channel MOS transistor P2 comes to the level "GND", the second p-channel MOS transistor P2 is turned on. Hence, the node 6 comes to the level "V DD " . At this time, since both the gate of the p-channel MOS transistor P4 and the node 6 are at the level "V DD ", the transistor P3 is turned off.
Furthermore, since both the gate of the third p-channel MOS transistor P3 and the node 6 are at the level "V DD ", the third p-channel MOS transistor P3 is turned off. Hence, a potential of the level "V DD " is output at the OUT1.
A case in which a potential which is lower than the level "V DD " is applied to the IN1 will be hereinafter explained with reference to FIG. 2.
When a potential of the level "V DD " is applied to the IN1, the gate of the n-channel MOS transistor N5 comes to at the level "V DD ", the transistor N5 is turned on, and the gate of the second p-channel MOS transistor P2 comes to at the level "GND". Hence, the second p-channel MOS transistor P2 is turned on. Consequently, the node 6 comes to at the level "V DD ", and since the gate of the transistor P4 is at the level "V DD ", the transistor P4 is turned off. In this aspect, the gate of the third p-channel MOS transistor P3 is at the level "V DD "and the transistor P3 is turned off. Furthermore, since a potential which is lower than the level "V DD ", is applied to the IN2, and the node 6 is at the level "V DD ", a parasitic diode D2 which exists between a source diffusion region (p-type) and n-well of the transistor P3 is reverse-biased, and the transistor P3 is not conducting. Hence, irrespective of the condition of the MOS transistor P1, it is possible to interrupt by the transistor P3 a current path between the level "V DD " 10 of the standard potential and the high-potential input terminal IN2 via the transistors P1, P3 and P2. Accordingly, it becomes possible to suppress a decrease in the output level at the output terminal OUT1 which is a disadvantage of the conventional power supply switching circuit, and to securely output the level "V DD " at the OUT1.
The present invention is not limited to the above-described aspects, but various modified aspects are possible within the scope of the invention.
For example, the present invention can be applied to an aspect in which a low potential, such as a negative power supply or the like, is used instead of a high-potential power supply. As an example thereof, p-channel and n-channel transistors may be replaced by n-channel and p-channel transistors, respectively, as shown in FIG. 3.
Furthermore, the level shifter 8 may be of any type provided that it can completely turn off the first MOS transistor P1. The third MOS transistor P3 may also have an arbitrary structure, provided that it effectively interrupts a current path between the level "V DD " 10 of the standard potential and the high-potential or low-potential input terminal IN2.
The power supply switching circuit of the present invention has the following effects.
In a power supply switching circuit according to claim 1, a third MOS transistor is provided between a first MOS transistor and an output terminal OUT. Hence, the third MOS transistor is turned off even when a potential applied from an input terminal IN2 is lower than the level "V DD " of a standard potential. Furthermore, a reverse bias is applied to a parasitic diode which exists between a source diffusion region and an n-well of the third MOS transistor to suppress a conduction between the standard potential and the input terminal. Accordingly, it makes it possible to securely output the level "V DD " at the OUT1, even when the potential applied from the input terminal is lower than the level "V DD " of the standard potential.
Although an exclusive terminal for applying a high potential is necessary in a conventional circuit, an input terminal for the high-potential level "V PP "and other input terminals for different potentials can be used in common in a power supply switching circuit. Hence, the present invention is effective in reducing the number of pins.
In a power supply switching circuit, the present invention can also be applied to an aspect in which a low potential, such as a negative potential and the like, is used, and an input terminal for a low potential level and other input terminals for different potentials can be used in common. Hence, the present invention is similarly effective in reducing the number of pins. | A power supply switching circuit includes first to third MOS transistors (P1, P2 and P3) connected in series between a high-potential source and a standard-potential source. The circuit performs a switching operation using a standard-potential and at least one potential which is different from the standard-poential, and outputs plural power supply potentials. The third MOS transistor (P3) is inserted between the first and second MOS transistors (P1 and P2). The back gate of the third transistor (P3) is connected to an output terminal (OUT1) formed between the second transistor (P2) and the third transistor (P3) and prevents the formation of a current path via turned-off transistor (P1) due to the action of a parasitic diode in the first and second transistors caused by potential fluctuations. | 7 |
The present invention relates generally to semiconductor devices, and more particularly, to photodiode transistor isolation technology for use in semiconductor devices, including CMOS image sensors.
BACKGROUND OF THE INVENTION
CMOS image sensors are increasingly being used as low cost imaging devices. A CMOS image sensor circuit includes a focal plane array of pixel cells, each one of the cells includes a photogate, photoconductor, or photodiode having an associated charge accumulation region within a substrate for accumulating photo-generated charge. Each pixel cell may include a transistor for transferring charge from the charge accumulation region to a sensing node, and a transistor, for resetting the sensing node to a predetermined charge level prior to charge transference. The pixel cell may also include a source follower transistor for receiving and amplifying charge from the sensing node and an access transistor for controlling the readout of the cell contents from the source follower transistor.
In a CMOS image sensor, the active elements of a pixel cell perform the necessary functions of: (1) photon to charge conversion; (2) accumulation of image charge; (3) transfer of charge to the sensing node accompanied by charge amplification; (4) resetting the sensing node to a known state before the transfer of charge to it; (5) selection of a pixel for readout; and (6) output and amplification of a signal representing pixel charge from the sensing node.
CMOS image sensors of the type discussed above are generally known as discussed, for example, in Nixon et al., “256×256 CMOS Active Pixel Sensor Camera-on-a-Chip,” IEEE Journal of Solid-State Circuits, Vol. 31(12), pp. 2046-2050 (1996); and Mendis et al., “CMOS Active Pixel Image Sensors,” IEEE Transactions on Electron Devices, Vol. 41(3), pp. 452-453 (1994). See also U.S. Pat. Nos. 6,177,333 and 6,204,524, which describe the operation of conventional CMOS image sensors and are assigned to Micron Technology, Inc., the contents of which are incorporated herein by reference.
A schematic diagram of a conventional CMOS pixel cell 10 is shown in FIG. 1 . The illustrated CMOS pixel cell 10 is a four transistor (4T) cell. The CMOS pixel cell 10 generally comprises a photo-conversion device 23 for generating and collecting charge generated by light incident on the pixel cell 10 , and a transfer transistor 17 for transferring photoelectric charges from the photo-conversion device 23 to a sensing node, typically a floating diffusion region 5 . The floating diffusion region 5 is electrically connected to the gate of an output source follower transistor 19 . The pixel cell 10 also includes a reset transistor 16 for resetting the floating diffusion region 5 to a predetermined voltage; and a row select transistor 18 for outputting a signal from the source follower transistor 19 to an output terminal in response to an address signal.
FIG. 2 is a cross-sectional view of a portion of the pixel cell 10 of FIG. 1 showing the photo-conversion device 23 , transfer transistor 17 and reset transistor 16 . The exemplary CMOS pixel cell 10 has a photo-conversion device 23 may be formed as a pinned photodiode. The photodiode 23 has a p-n-p construction comprising a p-type surface layer 22 and an n-type photodiode region 21 within a p-type active layer 11 . The photodiode 23 is adjacent to and partially underneath the transfer transistor 17 . The reset transistor 16 is on a side of the transfer transistor 17 opposite the photodiode 23 . As shown in FIG. 2 , the reset transistor 16 includes a source/drain region 2 . The floating diffusion region 5 is between the transfer and reset transistors 17 , 16 .
In the CMOS pixel cell 10 depicted in FIGS. 1 and 2 , electrons are generated by light incident on the photo-conversion device 23 and are stored in the n-type photodiode region 21 . These charges are transferred to the floating diffusion region 5 by the transfer transistor 17 when the transfer transistor 17 is activated. The source follower transistor 19 produces an output signal from the transferred charges. A maximum output signal is proportional to the number of electrons extracted from the n-type photodiode region 21 .
Conventionally, a shallow trench isolation (STI) region 3 adjacent to the charge collection region 21 is used to isolate the pixel cell 10 from other pixel cells and devices of the image sensor. The STI region 3 is typically formed using a conventional STI process. The STI region 3 is typically lined with an oxide liner 38 and filled with a dielectric material 37 . Also, the STI region 3 can include a nitride liner 39 . The nitride liner 39 provides several benefits, including improved corner rounding near the STI region 3 corners, reduced stress adjacent the STI region 3 , and reduced leakage for the transfer transistor 17 .
A common problem associated with a pixel cell is dark current—the discharge of the pixel cell's capacitance even though there is no light over the pixel. Dark current may be caused by many different factors, including: photodiode junction leakage, leakage along isolation edges, transistor sub-threshold leakage, drain induced barrier lower leakage, gate induced drain leakage, trap assisted tunneling, and other pixel defects. The obvious trend in the industry is to scale down the size of transistors in terms of both gate length and gate width (i.e., “scaling”). As devices are increasingly scaled down, dark current effect generally increases.
Therefore, it is desirable to have an improved isolation structure for reducing dark current and fixed pattern noise.
BRIEF SUMMARY OF THE INVENTION
A pixel cell is provided having a substrate with an isolation channel of higher carbon concentrate SiC provided in an exemplary embodiments of the invention. The channel comprising SiC or carbonated silicon is provided above the layer of Si in the substrate of the pixel cell to reduce the leakage of dark current.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other aspects of the invention will be better understood from the following detailed description of the invention, which is provided in connection with the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a conventional pixel cell;
FIG. 2 is a cross-sectional view of a conventional pixel cell;
FIG. 3 is a cross-sectional view of a pixel cell in accordance with an exemplary embodiment of the invention;
FIG. 4A depicts the pixel cell of FIG. 3 at an initial stage of processing;
FIGS. 4B-4L depict the pixel cell of FIG. 3 at intermediate stages of processing;
FIG. 5 is a cross-sectional view of a pixel cell according to another exemplary embodiment of the invention;
FIG. 6 is a cross-sectional view of a pixel cell according to yet another exemplary embodiment of the invention;
FIG. 7 is a block diagram of a CMOS image sensor according to an exemplary embodiment of the invention; and
FIG. 8 is a schematic diagram of a computer processor system incorporating the CMOS image sensor of FIG. 3 or 5 .
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof and illustrate specific embodiments in which the invention may be practiced. In the drawings, like reference numerals describe substantially similar components throughout the several views. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized, and that structural, logical and electrical changes may be made without departing from the spirit and scope of the present invention.
The terms “wafer” and “substrate” are to be understood as including silicon, silicon-on-insulator (SOI), silicon-on-sapphire (SOS), and silicon-on-nothing (SON) technology, doped and undoped semiconductors, epitaxial layers of silicon supported by a base semiconductor foundation, and other semiconductor structures. Furthermore, when reference is made to a “wafer” or “substrate” in the following description, previous process steps may have been utilized to form regions or junctions in the base semiconductor structure or foundation. In addition, the semiconductor need not be silicon-based, but could be based on silicon-germanium, germanium, or gallium-arsenide.
The term “pixel” or “pixel cell” refers to a picture element unit cell containing a photo-conversion device and transistors for converting electromagnetic radiation to an electrical signal. For purposes of illustration, a portion of a representative pixel cell is illustrated in the figures and description herein, and typically fabrication of all pixel cells in an image sensor will proceed concurrently and in a similar fashion.
FIG. 3 is a cross-sectional view of a pixel cell 300 according to an exemplary embodiment of the invention. The pixel cell 300 is similar to the pixel cell 10 depicted in FIGS. 1 and 2 , except that the pixel cell 300 includes an isolation channel 301 above the silicon layer 311 . The isolation channel 301 is preferably constructed of SiC or channeled carbonated Silicon. The use of a carbon rich layer of material increases the bandgap of the device. Isolation channel 301 has a higher bandgap than Si, typically sixteen (16) orders of magnitude lower than Si, and the resulting pixel cell 300 has a lower intrinsic carrier concentration. Therefore, the isolation channel 301 reduces the dark current level.
Until recently, growing high quality SiC substrates was prohibitively expensive and therefore SiC was used only in selective applications. Recent advances in growing SiC epitaxially have made it less expensive and decreased the defect densities. These advances have made it more possible to use SiC substrates in conventional applications. As the SiC channel can be built or grown on conventional Si layer and as part of a conventional Si process, it can be incorporated in a process that also forms a CMOS photodiode. Recent technological advances in forming the SiC layers can be found, for example, in “A new Si:C epitaxial channel nMosfet Architecture with improved drivability and short-channel characteristics”, T. Ernest et al, 2003 Symposium on VLSI Technology Digest of Technical Papers , pp. 2-93; “Fabrication of a novel strained SiGe:C-channel planar 55 nm nMosfet for High Performance CMOS”, T. Ernest et al, 2002 Symposium on VLSI Technology Digest of Technical Papers , pp. 92-93; and “Selective growth of high-quality 3C—SiC using a SiO2 sacrificial layer technique”, Thin Solid Films , Vol. 345 (2) (1999), pp. 19-99.
The use of SiC or Carbonated Silicon Channels as an isolation channel in a pixel cell reduces dark current levels. Because dark current levels are reduced, the present invention permits greater scaling in the pixel cells arrays. Greater scaling enables a larger fill factor.
The use of SiC or Carbonated Silicon Channels as an isolation channel in a pixel cell also creates additional advantages because of the inherent properties of the materials. Specifically, carbonated silicon materials permit a high temperature operation and enable a pixel cell the ability to sustain high electric fields. Additionally, these materials also have the property of effectively dissipating heat.
FIGS. 4A-4J depict the formation of pixel cell 300 according to an exemplary embodiment of the invention. The steps described herein need not be performed in any particular order, except for those logically requiring the results of prior actions. Accordingly, while the steps below are described as being performed in a general order, the order is exemplary only and can be altered if desired.
As illustrated in FIG. 4A , a pad oxide layer 441 , which can be a thermally grown oxide, is formed on the substrate 311 . A sacrificial layer 442 is formed on the pad oxide layer 441 . The sacrificial layer 442 can be a nitride or dielectric anti-reflective coating (DARC) layer.
FIG. 4B depicts the formation of a trench 430 in the substrate 11 and through the layers 441 , 442 on the substrate 311 . The trench 430 can be formed by any known technique. For example, a patterned photoresist layer (not shown) is used as a mask for an etching process. The first etch is conducted utilizing dry plasma conditions and difloromethane/carbon tetrafluoride (CH 2 F 2 /CF 4 ) chemistry. Such etching effectively etches both silicon nitride layer 442 and pad oxide layer 441 to form an opening extending therethrough which stops upon reaching the substrate 311 . A second etch is conducted to extend the openings into the substrate 311 . The second etch is a dry plasma etch utilizing difloromethane/hydrogen bromide (CH 2 F 2 /HBr) chemistry. The timing of the etch is adjusted to form the trench 430 within substrate 311 to the desired depth. A shorter etch time results in a shallower trench 430 . The photoresist mask (not shown) is removed using standard photoresist stripping techniques, preferably by a plasma etch.
A thin insulator layer 338 , between approximately 50 Å and approximately 250 Å thick, is formed on the trench 430 sidewalls 336 a , 336 b and bottom 308 , as shown in FIG. 4C . In the embodiment depicted in FIG. 4C , the insulator layer 338 is an oxide layer 338 is preferably grown by thermal oxidization.
The trench 430 can be lined with a barrier film 339 . In the embodiment shown in FIG. 4C , the barrier film 339 is a nitride liner, for example, silicon nitride. The nitride liner 339 is formed by any suitable technique, to a thickness within the range of approximately 50 Å to approximately 250 Å. Silicon nitride liner 339 can be formed by depositing ammonia (NH 3 ) and silane (SiH 4 ), as is known in the art.
The trench 430 is filled with a dielectric material 337 as shown in FIG. 4C . The dielectric material 337 may be an oxide material, for example a silicon oxide, such as SiO or silicon dioxide (SiO 2 ); oxynitride; a nitride material, such as silicon nitride; silicon carbide; a high temperature polymer; or other suitable dielectric material. In the illustrated embodiment, the dielectric material 337 is a high density plasma (HDP) oxide.
A chemical mechanical polish (CMP) step is conducted to remove the nitride layer 339 over the surface of the substrate 311 outside the trench 430 and the nitride layer 442 , as shown in FIG. 4E . Also, the pad oxide layer 441 is removed, for example, using a field wet buffered-oxide etch step and a clean step.
FIG. 4F depicts the formation of isolation channel 301 . The epitaxial isolation channel 301 is preferably grown by conventional means (e.g., the method outlined by Ernst, supra.). In a preferred embodiment, the epitaxial channel is grown at a low temperature. The isolation channel 301 in a preferred embodiment is preferably SiC or Carbonated Channel Silicon. The isolation channel 301 need not be grown uniformly; therefore, the depth of the isolation channel 301 over the field regions (e.g., trench 430 ) may be smaller than the depth of the layer of isolation channel over the non-field regions.
In a preferred embodiment, the carbon concentration is the isolation channel 301 is adjusted. It is known that controlling the temperature at which the Si:C is grown affects the carbon concentration of the isolation channel 301 .
In one embodiment of the invention, the isolation channel is only located in the transistor region. In another embodiment of the invention, the isolation channel is grown over another region of the substrate, e.g., a photo diode region. In yet another embodiment, the isolation channel is grown over the periphery array of the intended cell. In yet another embodiment, the isolation channel is grown over several regions, i.e., combinations of previously mentioned locations, for example, as shown in FIGS. 5 and 6 as described below. Although not shown, a nitride layer is formed prior to the formation of the isolation channel. The nitride deposition is patterned to expose particular areas to the formation of the isolation channel 301 depending on the aspect of the invention.
A planarization is conducted on the isolation channel 301 , resulting in a relatively uniform height of the layer as seen in FIG. 4G . The layer height can range from 100 Å to 500 Å, where the typical height is approximately 250 Å. In one embodiment of the invention, the height of the isolation channel 301 is approximately 250 Å above the non-field region and the height of the isolation channel 301 is less than approximately 250 Å above the field regions.
Following the planarization step, the nitride layer deposited prior to the formation of the isolation channel 301 is removed by a chemical mechanical polish (CMP) step. The nitride may be selectively removed depending on the embodiment of the invention. For example, in a certain embodiment, it may be desirable not to remove the nitride layer along the periphery of the cell.
FIG. 4H depicts the formation of the transfer transistor 317 ( FIG. 3 ) gate stack 407 and the reset transistor 316 ( FIG. 3 ) gate stack 406 . Although not shown, the source follower and row select transistors 19 , 18 ( FIG. 1 ), respectively, can be formed concurrently with the transfer and reset transistors 317 , 316 as described below.
To form the transistor gate stacks 407 , 406 as shown in FIG. 4H , a first insulating layer 401 a of, for example, silicon oxide is grown or deposited on the substrate 311 . In a preferred embodiment, the gate oxidation is formed by either rapid thermal oxidation (“RTO”) or in-site stem generation (ISSG). The first insulating layer 401 a serves as the gate oxide layer for the subsequently formed transistor gate 401 b . Next, a layer of conductive material 401 b is deposited over the oxide layer 401 a . The conductive layer 401 b serves as the gate electrode for the transistors 317 , 316 ( FIG. 3 ). The conductive layer 401 b may be a layer of polysilicon, which may be doped to a second conductivity type, e.g., n-type. A second insulating layer 401 c is deposited over the conductive layer 401 b . The second insulating layer 401 c may be formed of, for example, an oxide (SiO 2 ), a nitride (silicon nitride), an oxynitride (silicon oxynitride), ON (oxide-nitride), NO (nitride-oxide), or ONO (oxide-nitride-oxide).
The gate stack layers 401 a , 401 b , 401 c may be formed by conventional deposition methods, such as chemical vapor deposition (CVD) or plasma enhanced chemical vapor deposition (PECVD), among others. The layers 401 a , 401 b , 401 c are then patterned and etched to form the multilayer gate stacks 407 , 406 shown in FIG. 4F .
The invention is not limited to the structure of the gate stacks 407 , 406 described above. Additional layers may be added or the gate stacks 407 , 406 may be altered as is desired and known in the art. For example, a silicide layer (not shown) may be formed between the gate electrodes 401 b and the second insulating layers 401 c . The silicide layer may be included in the gate stacks 407 , 406 , or in all of the transistor gate stack structures in an image sensor circuit, and may be titanium silicide, tungsten silicide, cobalt silicide, molybdenum silicide, or tantalum silicide. This additional conductive layer may also be a barrier layer/refractor metal, such as titanium nitride/tungsten (TiN/W) or tungsten nitride/tungsten (WN x /W), or it could be formed entirely of tungsten nitride (WN x ).
Doped p-type wells 334 , 335 are implanted into the substrate 311 as shown in FIG. 4I . The first p-well 334 is formed in the substrate 311 surrounding the isolation region 333 and extending below the isolation region 333 . The second p-well 335 is formed in the substrate 311 from a point below the transfer gate stack 407 extending in a direction in the substrate 311 away from where the photodiode 323 ( FIG. 3 ) is to be formed.
The p-wells 334 , 335 are formed by known methods. For example, a layer of photoresist (not shown) can be patterned over the substrate 311 having an opening over the area where the p-wells, 334 , 335 are to be formed. A p-type dopant, such as boron, can be implanted into the substrate 311 through the opening in the photoresist. The p-wells 334 , 335 are formed having a p-type dopant concentration that is higher than adjacent portions of the substrate 311 . Alternatively, the p-wells 334 , 335 can be formed prior to the formation of the trench 430 .
As depicted in FIG. 4J , a doped n-type region 321 is implanted in the substrate 311 (for the photodiode 323 of FIG. 3 ). For example, a layer of photoresist (not shown) may be patterned over the substrate 311 having an opening over the surface of the substrate 311 where photodiode 323 ( FIG. 3 ) is to be formed. An n-type dopant, such as phosphorus, arsenic, or antimony, may be implanted through the opening and into the substrate 311 . Multiple implants may be used to tailor the profile of region 321 . If desired, an angled implantation may be conducted to form the doped region 321 , whereby the implantation is carried out at angles other than 90 degrees relative to the surface of the substrate 311 .
As shown in FIG. 4J , the n-type region 321 is formed from a point adjacent the transfer gate stack 407 and extending in the substrate 311 between the gate stack 407 and the isolation region 333 . The region 321 forms a photosensitive charge accumulating region for collecting photo-generated charge.
The floating diffusion region 305 and source/drain region 302 are implanted by known methods to achieve the structure shown in FIG. 4J . The floating diffusion region 305 and source/drain region 302 are formed as n-type regions. Any suitable n-type dopant, such as phosphorus, arsenic, or antimony, may be used. The floating diffusion region 305 is formed on the side of the transfer gate stack 407 opposite the n-type photodiode region 321 . The source/drain region 302 is formed on a side of the reset gate stack 406 opposite the floating diffusion region 305 .
FIG. 4K depicts the formation of a dielectric layer 307 . Illustratively, layer 307 is an oxide layer, but layer 307 may be any appropriate dielectric material, such as silicon dioxide, silicon nitride, an oxynitride, or tetraethyl orthosilicate (TEOS), among others, formed by methods known in the art.
The doped surface layer 322 for the photodiode 323 is implanted, as illustrated in FIG. 4L . Doped surface layer 322 is formed as a highly doped p-type surface layer and is formed to a depth of approximately 0.1 μm. A p-type dopant, such as boron, indium, or any other suitable p-type dopant, may be used to form the p-type surface layer 322 .
The p-type surface layer 322 may be formed by known techniques. For example, layer 322 may be formed by implanting p-type ions through openings in a layer of photoresist. Alternatively, layer 322 may be formed by a gas source plasma doping process, or by diffusing a p-type dopant into the substrate 311 from an in-situ doped layer or a doped oxide layer deposited over the area where layer 322 is to be formed.
The oxide layer 307 is etched such that remaining portions form a sidewall spacer on a sidewall of the reset gate stack 406 . The layer 307 remains over the transfer gate stack 407 , the photodiode 323 , the floating diffusion region 305 , and a portion of the reset gate stack 406 to achieve the structure shown in FIG. 3 . Alternatively, a dry etch step can be conducted to etch portions of the oxide layer 307 such that only sidewall spacers (not shown) remain on the transfer gate stack 407 and the reset gate stack 406 .
Conventional processing methods can be used to form other structures of the pixel 300 . For example, insulating, shielding, and metallization layers to connect gate lines, and other connections to the pixel 300 may be formed. Also, the entire surface may be covered with a passivation layer (not shown) of, for example, silicon dioxide, borosilicate glass (BSG), phosphosilicate glass (PSG), or borophosphosilicate glass (BPSG), which is CMP planarized and etched to provide contact holes, which are then metallized to provide contacts. Conventional layers of conductors and insulators may also be used to interconnect the structures and to connect pixel 300 to peripheral circuitry.
FIG. 5 depicts a pixel cell 500 in accordance with another exemplary embodiment of the invention. The pixel cell 500 is similar to the pixel cell 300 ( FIG. 3 ) except that isolation channel 507 is only applied to a portion of the image sensor array of pixel cell 500 .
FIG. 6 depicts a pixel cell 501 in accordance with another exemplary embodiment of the invention. The pixel cell 501 is similar to the pixel cell 300 ( FIG. 3 ) except that isolation channel 517 is only applied to a portion of the image sensor array of pixel cell 501 . In a preferred embodiment, the isolation channel 517 is applied to the source drain regions surrounding the array transistor and on the surface region of the photodiode 303 , as seen in FIG. 6 .
While the above embodiments are described in connection with the formation of p-n-p-type photodiodes the invention is not limited to these embodiments. The invention also has applicability to other types of photo-conversion devices, such as a photodiode formed from n-p or n-p-n regions in a substrate, a photogate, or a photoconductor. If an n-p-n-type photodiode is formed the dopant and conductivity types of all structures would change accordingly.
Although the above embodiments are described in connection with 4T pixel cell 300 , the configuration of pixel cell 300 is only exemplary and the invention may also be incorporated into other pixel circuits having different numbers of transistors. Without being limiting, such a circuit may include a three-transistor (3T) pixel cell, a five-transistor (5T) pixel cell, a six-transistor (6T) pixel cell, and a seven-transistor pixel cell (7T). A 3T cell omits the transfer transistor, but may have a reset transistor adjacent to a photodiode. The 5T, 6T, and 7T pixel cells differ from the 4T pixel cell by the addition of one, two, or three transistors, respectively, such as a shutter transistor, a CMOS photogate transistor, and an anti-blooming transistor. Further, while the above embodiments are described in connection with CMOS pixel cell 300 the invention is also applicable to pixel cells in a charge coupled device (CCD) image sensor.
A typical single chip CMOS image sensor 600 is illustrated by the block diagram of FIG. 7 . The image sensor 600 includes a pixel cell array 680 having one or more pixel cell 300 , 500 , or 501 ( FIGS. 3 , 5 , or 6 respectively) described above. The pixel cells of array 680 are arranged in a predetermined number of columns and rows.
The rows of pixel cells in array 680 are read out one by one. Accordingly, pixel cells in a row of array 680 are all selected for readout at the same time by a row select line, and each pixel cell in a selected row provides a signal representative of received light to a readout line for its column. In the array 680 , each column also has a select line, and the pixel cells of each column are selectively read out in response to the column select lines.
The row lines in the array 680 are selectively activated by a row driver 682 in response to row address decoder 681 . The column select lines are selectively activated by a column driver 684 in response to column address decoder 685 . The array 680 is operated by the timing and control circuit 683 , which controls address decoders 681 , 685 for selecting the appropriate row and column lines for pixel signal readout.
The signals on the column readout lines typically include a pixel reset signal (V rst ) and a pixel image signal (V photo ) for each pixel cell. Both signals are read into a sample and hold circuit (S/H) 686 in response to the column driver 684 . A differential signal (V rst −V photo ) is produced by differential amplifier (AMP) 687 for each pixel cell, and each pixel cell's differential signal is digitized by analog-to-digital converter (ADC) 688 . The analog-to-digital converter 688 supplies the digitized pixel signals to an image processor 689 , which performs appropriate image processing before providing digital signals defining an image output.
FIG. 8 illustrates a processor-based system 700 including the image sensor 600 of FIG. 7 . The processor-based system 700 is exemplary of a system having digital circuits that could include image sensor devices. Without being limiting, such a system could include a computer system, camera system, scanner, machine vision, vehicle navigation, video phone, surveillance system, auto focus system, star tracker system, motion detection system, and other systems requiring image acquisition.
The processor-based system 700 , for example a camera system, generally comprises a central processing unit (CPU) 795 , such as a microprocessor, that communicates with an input/output (I/O) device 791 over a bus 793 . Image sensor 600 also communicates with the CPU 795 over bus 793 . The processor-based system 700 also includes random access memory (RAM) 792 , and can include removable memory 794 , such as flash memory, which also communicate with CPU 795 over the bus 793 . Image sensor 600 may be combined with a processor, such as a CPU, digital signal processor, or microprocessor, with or without memory storage on a single integrated circuit or on a different chip than the processor.
It is again noted that the above description and drawings are exemplary and illustrate preferred embodiments that achieve the objects, features and advantages of the present invention. It is not intended that the present invention be limited to the illustrated embodiments. Any modification of the present invention which comes within the spirit and scope of the following claims should be considered part of the present invention. For example, although described the exemplary embodiment is described with reference to a CMOS p-n-p pixel cell, the invention is not limited to that structure (e.g., and is applicable to other configurations of pixel cells, both active and passive), nor is the invention limited to that technology (e.g., and is applicable to CCD technology as well). | A pixel cell having a substrate with a isolation channel formed of higher carbon concentrate such as SiC or carbonated silicon. The channel comprising SiC or carbonated silicon is provided over the substrate of the pixel cell to reduce the dark current leakage. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation application of U.S. patent application Ser. No. 13/452,286, filed Apr. 20, 2012, which is a Continuation application of U.S. patent application Ser. No. 12/172,577, filed on Jul. 14, 2008, and issued as U.S. Pat. No. 8,266,394, which are commonly assigned, and incorporated herein by reference in their entireties.
GOVERNMENT RIGHTS
This invention was made with Government support under Contract No.: HR0011-07-9-0002. The Government has certain rights in this invention.
BACKGROUND
Technical Field
The present invention relates to information protection and queues and, more particularly, to methods for single-owner multi-consumer work queues for repeatable tasks.
Description of the Related Art
Single-owner multi-consumer work queues, also commonly referred to as work stealing queues, are typically used to hold the work created by a thread, while allowing other threads to steal work if their own work queues are empty. Since a work queue may be accessed concurrently by the queue's owner and other threads attempting to steal work, synchronization is needed. In particular, the thread's owner is required to use “special” atomic instructions (e.g., compare-and-swap instructions, also interchangeably referred to herein by the acronym “CAS”), which are typically significantly slower than regular instructions.
In general, each task in the work queue should be extracted exactly once from the queue (and hence performed exactly once, e.g., transfer money). However, in many other cases (e.g., perform a calculation), it is acceptable for tasks to be performed one or more times, i.e., when tasks are idempotent. For such latter class of tasks (i.e., those tasks to be performed one or more times), this should be an opportunity to design work stealing queues that guarantee correct concurrent access with less synchronization overheads than work stealing queues that guarantee that each task is extracted exactly once.
SUMMARY
The shortcomings of the prior art are overcome and additional advantages are provided through the provision of methods for lock-free work stealing queue for repeatable tasks.
According to an aspect of the present principles, there is provided a method. The method includes permitting a single owner thread of a single owner, multi-consumer, work queue to access the work queue using atomic instructions limited to only a single access and using non-atomic operations. The method further includes restricting the single owner thread from accessing the work queue using atomic instructions involving more than one access. The method also includes synchronizing amongst other threads with respect to their respective accesses to the work queue.
According to another aspect of the present principles, there is provided a program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform method steps for queue access management. The method steps include permitting a single owner thread of a single owner, multi-consumer, work queue to access the work queue using atomic instructions limited to only a single access and using non-atomic operations. The method steps further include restricting the single owner thread from accessing the work queue using atomic instructions involving more than one access. The method steps also include synchronizing amongst other threads with respect to their respective accesses to the work queue.
These and other features and advantages will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
The disclosure will provide details in the following description of preferred embodiments with reference to the following figures wherein:
FIG. 1 shows an exemplary work queue 100 with two tasks, to which the present principles may be applied, in accordance with an embodiment of the present principles;
FIGS. 2A, 2B, and 2C respectively show exemplary methods 200 , 230 , and 260 relating to double-ended extraction on a work queue, in accordance with an embodiment of the present principles;
FIG. 3 shows an exemplary work queue 300 with two tasks, to which the present principles may be applied, in accordance with an embodiment of the present principles;
FIGS. 4A, 4B, and 4C respectively show exemplary methods 400 , 430 , and 460 relating to double-ended extraction on a work queue, in accordance with an embodiment of the present principles;
FIGS. 5A and 5B respectively show exemplary methods 530 and 560 relating to first in first out (FIFO) extraction on a work queue, in accordance with an embodiment of the present principles;
FIG. 6 shows an exemplary work queue 600 with two tasks, to which the present principles may be applied, in accordance with an embodiment of the present principles; and
FIGS. 7A, 7B, and 7C respectively show exemplary methods 700 , 730 , and 760 relating to last in first out (LIFO) extraction on a work queue, in accordance with an embodiment of the present principles.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
As noted above, the present principles are directed to methods for lock-free work stealing queue for repeatable tasks.
In an embodiment, the present principles permit the queue owner to perform its operations (insertion and extraction) from the queue without regard for concurrent stealing operations. Thus, in an embodiment, the operations of the queue owner do not use any complex or special atomic instructions (as explicitly defined herein). On the other hand, the stealing threads (thieves) synchronize among each other in order to maintain the integrity of the queue.
In an embodiment, in order to maintain the integrity of the queue even when the owner is not using atomic operations, the owner never writes shared variables written by thieves (other than for initialization) and thieves never write shared variables written by the owner.
FIG. 1 shows an exemplary work queue 100 with two tasks, to which the present principles may be applied, in accordance with an embodiment of the present principles.
The reference character W represents a circular array of work items of size M. With respect to array W, the queue owner puts work items into the array, and the owner and other threads may take work items from the array. During normal queue operations (put, take, and steal), the size of the array is treated as constant. However, the owner of the queue can resize the array in a straightforward manner as described herein.
The reference character H denotes a single variable that can be accessed atomically. H includes three integer components corresponding to the head of the work queue 100 , the size of the work queue 100 , and tag for the work queue 100 , respectively. The head of the work queue corresponds to the index of the head of the work queue, i.e., the next item to be extracted from the queue by threads other than the queue owner's thread. The size of the work queue corresponds to the number of items in the work queue 100 . The tag for the work queue is a number that is incremented on every extraction. Preferably, the size of the tag is large enough (e.g., 40 bits) such that it is impossible for the tag to make a complete wrap-around during a single operation on the queue by a thread. The initial value of H is all zeros.
FIGS. 2A, 2B, and 2C respectively show exemplary methods 200 , 230 , and 260 relating to double-ended extraction on a work queue, in accordance with an embodiment of the present principles. In further detail, the method 200 of FIG. 2A corresponds to a Put(w) operation, the method 230 of FIG. 2B corresponds to a Take( ) operation, and the method 260 of FIG. 2C corresponds to a Steal( ) operation, each corresponding to double-ended extraction on a work queue. The methods 200 , 230 , and 260 may be applied, for example, to the work queue 100 of FIG. 1 .
Initially, the Put(w) operation will be generally described, following by a description of the method 200 of FIG. 2A . Only the owner thread (i.e., owner) of the queue can perform a Put(w) operation on the queue. The owner puts a new work item at the tail end of the work queue. The Put(w) operation takes as a parameter the work item to be added to the queue.
Referring to method 200 of FIG. 2A , at step 204 , three integer values (corresponding to head, size, and tag, respectively) are atomically read from a variable H into local variables h, s, and tag, respectively. At step 208 , it is then determined whether or not the value of s is equal to the capacity of the queue (i.e., the size M of the array W).
If so (i.e., the value of S is equal to M), then at step 212 , an indicator is provided that the queue is full. In such a case, the owner of the queue may be permitted to decide the next course of action including, but not limited to, extending the size of the array W.
If the value of S is not equal to M (i.e., it is smaller than M), then at step 216 , the queue owner writes the item w into the entry of array W with index h+s % M. This write operation does not have to be atomic.
At step 220 , the queue owner atomically writes to the variable H the three values h, s+1, tag. That is, the head index is unchanged, but the size of the queue has increased by one.
At step 224 , the Put(w) operation returns a success indicator.
With respect to the Take( ) operation, initially, the Take( ) operation will be generally described, following by a description of the method 230 of FIG. 2B . Only the owner thread (i.e., owner) of the queue can perform a Take( ) operation on the queue. The Take( ) operation returns a work item that was put earlier by the owner thread, or an indictor of an empty queue if the queue is empty. The Take( ) operation extracts a work item from the tail end of the queue, i.e., the most recent item put in the queue by the owner.
Referring to FIG. 2B , at step 234 , three integer values (head, size, tag) are atomically read from variable H into local variables h, s, and tag, respectively. At step 238 it is determined whether or not s is equal to zero.
If so (i.e., the value of S is equal to zero), then at step 242 , an indicator is provided that the queue is empty.
If the value of S is not equal to zero (i.e., it is greater than zero), then at step 246 , the queue owner reads the entry of array W with index h+s−1% M (i.e., the most recently added item). This read operation does not have to be atomic.
At step 250 , the owner writes atomically to the variable H the three values h s−1, and tag+1. That is, the head index is unchanged, but the size of the queue has decreased by one, and the extraction tag is incremented.
At step 254 , the Take( ) operation returns the extracted item.
With respect to the Steal( ) operation, initially, the Steal( ) operation will be generally described, following by a description of the method 260 of FIG. 2C . A Steal( ) operation is executed by a thread different (hereinafter referred to as “other thread” or “other thread(s)”) from the thread owner. Typically, the other thread has an empty work queue, and hence is looking to help other threads with their work. The Steal( ) operation returns a work item that was put in the queue by the queue's owner, an indicator of an empty queue if the queue is empty, or an indicator of conflict. The Steal( ) operation extracts a work item from the head of the queue, i.e., the oldest item in the queue.
Referring to FIG. 2C , at step 264 , three integer values (corresponding to head, size, tag) are atomically read from a variable H into local variables h, s, and tag, respectively. At step 268 , it is determined whether or not s is equal to zero.
If so (i.e., the value of S is equal to zero), then at step 272 , an indicator is provided that the queue is empty.
If the value of S is not equal to zero (i.e., it is greater than zero), then at step 276 , the other thread reads the entry of array W with index h, i.e., at the head of the queue. This read need not be atomic.
At step 280 , the other thread atomically checks that the value of H is the same as that read in the first step (i.e., step 264 ).
If not (i.e., the value of H is different), then at step 292 , an indicator is provided that a conflict exists. In such a case, the other thread may be permitted to decide on the next course of action including, but not limited to, for example, retrying the operation on this work queue or trying a different work queue.
If the value of H is the same (between steps 264 and 280 ), then at step 284 , the other thread writes to H the three values h+1% M, s−1, tag+1. The read-check-write are all done atomically using complex atomic instructions such as, but not limited to, for example, compare-and-swap.
At step 288 , the Steal( ) operation returns the extracted item.
In an embodiment, the methods 200 , 230 , and 260 of FIGS. 2A, 2B, and 2C , respectively, may be represented by the following pseudo code. In the following pseudo code, the operations Put(w) and Take( ) are performed by the owner only.
Structures
H: <integer,integer,integer> // <Head,Size,Tag>
W: array of tasks of size M
Initialization
H := <0,0,0>
Put(w)
1
<h,s,tag> := H
if (s == M) return FULL
2
W[h+s%M] := w
3
H := <h,s+1,tag>
return SUCCESS
Take( )
1
<h,s,tag> := H
if (s == 0) return EMPTY
2
w := [h+s−1%M]
3
H := <h,s−1,tag+1>
return w
Steal( )
1
<h,s,tag> := H
if (s == 0) return EMPTY
2
w := [h%M]
3
if !CAS(H,<h,s,tag>,<h+1%M,s−1,tag+1>) return CONFLICT
return w
It should be understood that the elements shown in the FIGURES may be implemented in various forms of hardware, software or combinations thereof. Preferably, these elements are implemented in software on one or more appropriately programmed general-purpose digital computers having a processor and memory and input/output interfaces.
Embodiments of the present invention can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment including both hardware and software elements. In a preferred embodiment, the present invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, etc.
Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer readable medium can be any apparatus that may include, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read/write (CD-R/W) and DVD.
A data processing system suitable for storing and/or executing program code may include at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code to reduce the number of times code is retrieved from bulk storage during execution. Input/output or I/O devices (including but not limited to keyboards, displays, pointing devices, etc.) may be coupled to the system either directly or through intervening I/O controllers.
Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters.
Reference in the specification to “one embodiment” or “an embodiment” of the present principles, as well as other variations thereof, means that a particular feature, structure, characteristic, and so forth described in connection with the embodiment is included in at least one embodiment of the present principles. Thus, the appearances of the phrase “in one embodiment” or “in an embodiment”, as well any other variations, appearing in various places throughout the specification are not necessarily all referring to the same embodiment.
It is to be appreciated that the use of any of the following “/”, “and/or”, and “at least one of”, for example, in the cases of “A/B”, “A and/or B” and “at least one of A and B”, is intended to encompass the selection of the first listed option (A) only, or the selection of the second listed option (B) only, or the selection of both options (A and B). As a further example, in the cases of “A, B, and/or C” and “at least one of A, B, and C”, such phrasing is intended to encompass the selection of the first listed option (A) only, or the selection of the second listed option (B) only, or the selection of the third listed option (C) only, or the selection of the first and the second listed options (A and B) only, or the selection of the first and third listed options (A and C) only, or the selection of the second and third listed options (B and C) only, or the selection of all three options (A and B and C). This may be extended, as readily apparent by one of ordinary skill in this and related arts, for as many items listed.
As used herein, the word “owner” and the phrases “thread owner”, “owner thread”, and variations thereof, each interchangeably refer to a thread that currently has ownership (e.g., a lock) on a particular queue. The particular queue may be referred to as the “owned queue” and variations thereof.
Moreover, as used herein, the phrase “atomic operation” refers to a set of operations that can be combined so that they appear to be (to a corresponding system in which they are used) single operation. Examples of atomic instructions include a read only, a write only, and so forth, where each of these instructions involves only one access.
Further, as used herein, the phrases “complex atomic instruction” and “special atomic instruction” interchangeably refer to atomic instructions that necessarily involve more than one access. Examples of complex atomic instructions include a read-modify-write, a read-check-write, and so forth. The read and the write are accesses to shared memory, while the check and modify are applied privately to the read value.
FIG. 3 shows an exemplary work queue 300 with two tasks, to which the present principles may be applied, in accordance with an embodiment of the present principles.
The reference character W represents a circular array of work items of size M. With respect to array W, the queue owner puts work items into the array, and the owner and other threads may take work items from the array. During normal queue operations (put, take, and steal), the size of the array is treated as constant. However, the owner of the queue can resize the array in a straightforward manner as described herein.
The reference character H denotes a single integer variable indicating the head of the queue. The initial value of H is zero.
The reference character T denotes a single integer variable indicating the tail of the queue. The initial value of T is zero.
FIGS. 4A, 4B, and 4C respectively show exemplary methods 400 , 430 , and 460 relating to double-ended extraction on a work queue, in accordance with an embodiment of the present principles. In further detail, the method 400 of FIG. 4A corresponds to a Put(w) operation, the method 430 of FIG. 4B corresponds to a Take( ) operation, and the method 460 of FIG. 4C corresponds to a Steal( ) operation, each corresponding to double-ended extraction on a work queue. The methods 400 , 430 , and 460 may be applied, for example, to the work queue 300 of FIG. 3 .
Initially, the Put(w) operation will be generally described, following by a description of the method 400 of FIG. 4A . Only the owner thread (i.e., owner) of the queue can perform a Put(w) operation on the queue. The owner puts a new work item at the tail end of the work queue. The Put(w) operation takes as a parameter the work item to be added to the queue.
Referring to method 400 of FIG. 4A , at step 404 , the owner atomically reads the value from T into local variable t.
At step 408 , the owner atomically reads the value from H into local variable h.
At step 412 , it is determined if t-h is equal to M.
If so (i.e., if t-h is equal to M), then at step 416 , an indicator is provided that the queue is full.
If t-h is not equal to M, then at step 420 , the owner writes the item w into the entry of array W with index t % M. This write operation does not have to be atomic.
At step 424 , the owner atomically writes the value t+1 to the shared variable T.
At step 428 , the Put(w) operation returns a success indicator.
Initially, the Take( ) operation will be generally described, following by a description of the method 230 of FIG. 2B . Only the owner thread (i.e., owner) of the queue can perform a Take( ) operation on the queue. The Take( ) operation returns a work item that was put earlier by the owner thread, or an indictor of an empty queue if the queue is empty. The Take( ) operation extracts a work item from the tail end of the queue, i.e., the most recent item put in the queue by the owner.
Referring to FIG. 4B , at step 432 , the value of T is atomically read, and the value of T minus 1 is kept in a local variable t.
At step 434 , the owner atomically writes the value of local variable t into the shared variable T.
At step 436 , the owner atomically reads the value from H into a local variable h.
At step 438 , it is determined whether or not t is smaller than h (i.e., the queue is empty).
If so (i.e., t is smaller than h), then at step 440 , the owner writes the value h into T. At step 442 , the Take( ) operation returns an empty queue indicator.
If t is not smaller than h, then at step 444 , it is determined whether or not t is equal to h.
If so (i.e., t is equal to h), then at step 446 , the owner atomically writes the value h+1 into T. At step 448 , the owner atomically writes h+1 into H.
If t is not equal to h (and also following step 448 ), the Take( ) operation returns the item with index t % M in the array W.
With respect to the Steal( ) operation, initially, the Steal( ) operation will be generally described, following by a description of the method 460 of FIG. 4C . A Steal( ) operation is executed by a thread different (hereinafter referred to as “other thread” or “other thread(s)”) from the thread owner. Typically, the other thread has an empty work queue, and hence is looking to help other threads with their work. The Steal( ) operation returns a work item that was put in the queue by the queue's owner, an indicator of an empty queue if the queue is empty, or an indicator of conflict. The Steal( ) operation extracts a work item from the head of the queue, i.e., the oldest item in the queue.
Referring to FIG. 4C , at step 462 , the Steal( ) operation atomically reads from variable H into local variable h.
At step 464 , the other thread(s) atomically reads from variable T into local variable t.
At step 466 , it is determined whether or not h is greater than or equal to t.
If so (h is greater than or equal to t), then at step 468 , an indicator is provided of an empty queue.
If h is not greater than or equal to t, then at step 470 , the other thread(s) reads the entry of array W with index h, i.e., at the head of the queue. This read operation does not have to be atomic.
At step 472 , it is determined whether or not the value H is the same as that read in the first step (i.e., step 462 ). The read-check-write in steps 472 and 476 are complex atomic instructions.
If not (i.e., the value of H is different), then at step 474 , an indicator is provided that a conflict exists. In such a case, the other thread may be permitted to decide on the next course of action including, bit not limited to, retrying the operation on this work queue or trying a different work queue.
If the value of H is the same (between steps 462 and 472 ), then at step 476 , the other thread(s) atomically writes the value h+1 to H.
At step 480 , the Steal( ) operation returns the extracted item.
In an embodiment, the methods 400 , 430 , and 460 of FIGS. 4A, 4B, and 4C , respectively, may be represented by the following pseudo code. In the following pseudo code, the operations Put(w) and Take( ) are performed by the owner only.
Structures
H: integer // Head
T: integer // Tail
W: array of tasks of size M
Initialization
H := 0
T := 0
Put(w)
1
t := T
2
h := H
if (t−h == M) return FULL
3
W[t%M] := w
4
T := t+1
return SUCCESS
Take( )
1
t := T−1
2
T := t
3
h := H
4
if (t<h) T := h; return EMPTY
if (t==h)
5
T := h+1
6
H := h+1
7
return W[t%M]
Steal( )
1
h := H
2
t := T
if (h>=t) return EMPTY
3
w := W[h%M]
4
if !CAS(H,h,h+1) return CONFLICT
return w
FIGS. 5A and 5B respectively show exemplary methods 530 and 560 relating to first in first out (FIFO) extraction on a work queue, in accordance with an embodiment of the present principles. In further detail, the method 530 of FIG. 5A corresponds to a Take( ) operation and the method 560 of FIG. 5B corresponds to a Steal( ) operation, each corresponding to first in first out (FIFO) extraction on a work queue. The methods 530 and 560 may be applied, for example, to the work queue 300 of FIG. 3 . It is to be noted that the Put(w) operation relating to first in first out extraction on a work queue is the same as that described for the Put(w) operation of FIG. 4A (and is, hence, not reproduced again with respect to FIFO extraction for reasons of brevity).
Initially, the Take( ) operation will be generally described, following by a description of the method 530 of FIG. 5A . Only the owner thread (i.e., owner) of the queue can perform a Take( ) operation on the queue. The Take( ) operation returns a work item that was put earlier by the owner thread, or an indictor of an empty queue if the queue is empty. The Take( ) operation extracts a work item from the head end of the queue, i.e., the oldest item put in the queue by the owner.
Referring to FIG. 5A , at step 534 , the Take( ) operations atomically reads the value of H into a local variable h.
At step 538 , the owner atomically reads the value from T into a local variable t.
At step 542 , it is determined whether or not h is equal to t.
If so (i.e., h is equal to t), then at step 546 , an indicator is provided that the queue is empty.
If h is not equal to t, then at step 550 , the owner reads the entry of array W with index h % M, i.e., the oldest item in the queue. This read operation does not have to be atomic.
At step 554 , the owner atomically writes the value h+1 into H.
At step 558 , the Take( ) operation returns the extracted item.
With respect to the Steal( ) operation, initially, the Steal( ) operation will be generally described, following by a description of the method 560 of FIG. 5B . A Steal( ) operation is executed by a thread different (hereinafter referred to as “other thread” or “other thread(s)”) from the thread owner. Typically, the other thread has an empty work queue, and hence is looking to help other threads with their work. The Steal( ) operation returns a work item that was put in the queue by the queue's owner, an indicator of an empty queue if the queue is empty, or an indicator of conflict. The Steal( ) operation extracts a work item from the head of the queue, i.e., the oldest item in the queue.
Referring to FIG. 5B , at step 564 , the Steal( ) operation atomically reads from variable H into local variable h.
At step 568 , the other thread(s) atomically reads from the variable T into a local variable t.
At step 572 , it is determined whether or not h is equal to t.
If so (i.e., h is equal to t), then at step 576 , an indicator is provided of an empty queue.
If h is not equal to t, then at step 580 , the other thread(s) reads the entry of array W with index h % M, i.e., at the head of the queue. This read operation does not have to be atomic.
At step 584 , it is determined whether or not the value of H is the same as that read in the first step (i.e., step 564 ).
If not (i.e., the value of H is different), then at step 588 , an indicator is provided that a conflict exists. In such a case, the other thread may be permitted to decide on the next course of action including, but not limited to, retrying the operation on this work queue or trying a different work queue.
If the value of H is the same (between steps 564 and 584 , then at step 592 , the other thread(s) atomically writes the value h+1 into H. It is to be noted that read-check-write in steps 592 and 596 are complex atomic instructions.
At step 596 , the Steal( ) operation returns the extracted item.
In an embodiment, the method 530 and 560 of FIGS. 5A and 5B and 5C , respectively, may be represented by the following pseudo code. In the following pseudo code, the operations Put(w) and Take( ) are performed by the owner only. It is to be that noted pseudo code for a Put(w) operation corresponding to first out (FIFO) extraction on a work queue may be represented by the pseudo code provided above with respect to the method 400 of FIG. 4A .
Structures
H: integer // Head
T: integer // Tail
W: array of tasks of size M
Initialization
H := 0
T := 0
Take( )
1
h := H
2
t := T
if (h == t) return EMPTY
3
w := W[h%M]
4
H := h+1
return w
Steal( )
1
h := H
2
t := T
if (h == t) return EMPTY
3
w := [h%M]
4
if !CAS(H,h,h+1) return CONFLICT
return w
FIG. 6 shows an exemplary work queue 600 with two tasks, to which the present principles may be applied, in accordance with an embodiment of the present principles.
The reference character W represents a circular array of work items of size M. With respect to array W, the queue owner puts work items into the array, and the owner and other threads may take work items from the array. During normal queue operations (put, take, and steal), the size of the array is treated as constant. However, the owner of the queue can resize the array in a straightforward manner as described herein.
The reference character T denotes a single variable that can be accessed atomically. T includes two integer components corresponding to the tail of the work queue 600 and tag for the work queue 600 , respectively. The tail of the work queue corresponds to the index of the tail end of the work queue. The tag for the work queue is a number that is incremented on every extraction. Preferably, the size of the tag is large enough (e.g., 40 bits) such that it is impossible for the tag to make a complete wrap-around during a single operation on the queue by a thread. The initial value of T is all zeros.
FIGS. 7A, 7B, and 7C respectively show exemplary methods 700 , 730 , and 760 relating to last in first out (LIFO) extraction on a work queue, in accordance with an embodiment of the present principles. In further detail, the method 700 of FIG. 7A corresponds to a Put(w) operation, the method 730 of FIG. 7B corresponds to a Take( ) operation, and the method 760 of FIG. 7C corresponds to a Steal( ) operation, each corresponding to last in first out (LIFO) extraction on a work queue. The methods 700 , 730 , and 760 may be applied, for example, to the work queue 600 of FIG. 6 .
Initially, the Put(w) operation will be generally described, following by a description of the method 700 of FIG. 7A . Only the owner thread (i.e., owner) of the queue can perform a Put(w) operation on the queue. The owner puts a new work item at the tail end of the work queue. The Put(w) operation takes as a parameter the work item to be added to the queue.
Referring to method 700 of FIG. 7A , at step 704 , the Put(w) operation atomically reads two integer values (corresponding to tail and tag, respectively) are atomically read from variable T into local variables t and tag.
At step 708 , it is determined whether or not t is equal to the capacity of the queue (i.e., the size M of the array W).
If so (i.e., the value of t is equal to M), then at step 712 , an indicator is provided that the queue is full. In such a case, the owner of the queue may be permitted to decide the next course of action including, but not limited to, extending the size of the array W.
If the value of t is not equal to M (e.g., it is smaller than M), then at step 716 , the owner writes the item w into the entry of array W with index t. This write operation does not have to be atomic.
At step 720 , the queue owner atomically writes to the variable T the two values t+1 and tag.
At step 724 , the Put(w) operation returns a success indicator.
With respect to the Take( ) operation, initially, the Take( ) operation will be generally described, following by a description of the method 730 of FIG. 7B . Only the owner thread (i.e., owner) of the queue can perform a Take( ) operation on the queue. The Take( ) operation returns a work item that was put earlier by the owner thread, or an indictor of an empty queue if the queue is empty. The Take( ) operation extracts a work item from the tail end of the queue, i.e., the most recent item put in the queue by the owner.
Referring to FIG. 7B , at step 734 , the Take( ) operations atomically reads two integer values (corresponding to tail and tag, respectively) from variable T into local variables t and tag.
At step 738 , it is determined whether or not t is equal to zero.
If so (i.e., the value of t is equal to zero), then at step 742 , an indicator is provided that the queue is empty.
If the value of t is not equal to zero, then at step 746 , the owner reads the entry of array W with index t−1, i.e., the most recently added item. This read operation does not have to be atomic.
At step 750 , the owner atomically writes to the variable T the two values t−1 and tag+1.
At step 754 , the Take( ) operation returns the extracted item.
With respect to the Steal( ) operation, initially, the Steal( ) operation will be generally described, following by a description of the method 760 of FIG. 7C . A Steal( ) operation is executed by a thread different (hereinafter referred to as “other thread” or “other thread(s)”) from the thread owner. Typically, the other thread has an empty work queue, and hence is looking to help other threads with their work. The Steal( ) operation returns a work item that was put in the queue by the queue's owner, an indicator of an empty queue if the queue is empty, or an indicator of conflict. The Steal( ) operation extracts a work item from the tail of the queue, i.e., the most recent item in the queue.
Referring to FIG. 7C , at step 764 , the Steal( ) operation atomically reads two integer values (corresponding to tail and tag, respectively) from variable T into local variables t and tag.
At step 768 , it is determined whether or not t is equal to zero.
If so (i.e., if t is equal to zero), then at step 772 , an indicator is provided that the queue is empty.
If the value of t is not equal to zero, then at step 776 , the other thread(s) read the entry of array W with index t−1. This read operation does not have to be atomic.
At step 780 , it is determined whether or not the value of t is the same as that read in the first step (i.e., step 764 ).
If not (i.e., the value of t is different), then at step 784 , an indicator is provided that a conflict exists. In such a case, the other thread may be permitted to decide on the next course of action including, but not limited to, retrying the operation on this work queue or trying a different work queue.
If the value of t is the same (between steps 764 and 780 ), then at step 788 , the other thread atomically writes to the variable H the two values t−1 and tag+1. It is to be noted that the read-check-write steps of 780 and 788 are complex atomic instructions.
At step 792 , the Steal( ) operation returns the extracted item.
In an embodiment, the methods 700 , 730 , and 760 of FIGS. 7A, 7B, and 7C , respectively, may be represented by the following pseudo code. In the following pseudo code, the operations Put(w) and Take( ) are performed by the owner only.
Structures
T: <integer,integer> // <Tail,Tag>
W: array of tasks of size M
Initialization
T := <0,0>
Put(w)
1
t,tag := T
if (t == M) return FULL
2
W[t] := w
3
T := <t+1,tag>
return SUCCESS
Take( )
1
<t,tag> := T
if (t == 0) return EMPTY
2
w := W[t−1]
3
T := <t−1,tag+1>
return w
Steal( )
1
<t,tag> := T
if (t == 0) return EMPTY
2
w := W[t−1]
3
if !CAS(T,<t,tag>,<t−1,tag+1>) return CONFLICT
return w
One or more extensions of the present principles, in accordance with one or more embodiments thereof will now be described. For example, in an embodiment, any of the queues described herein can be grown unbounded. The owner can simply replace the circular array with another circular array with a different size after copying the items in the old array to the corresponding locations (modulo array sizes) in the new array. In systems with automatic garbage collection, the old array is reclaimed automatically. In systems with explicit memory de-allocation, using any of the known safe memory reclamation methods, such as hazard pointers, can be used to reclaim the old array.
Having described preferred embodiments of methods (which are intended to be illustrative and not limiting), it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is therefore to be understood that changes may be made in the particular embodiments disclosed which are within the scope and spirit of the invention as outlined by the appended claims. Having thus described aspects of the invention, with the details and particularity required by the patent laws, what is claimed and desired protected by Letters Patent is set forth in the appended claims. | There are provided methods for single-owner multi-consumer work queues for repeatable tasks. A method includes permitting a single owner thread of a single owner, multi-consumer, work queue to access the work queue using atomic instructions limited to only a single access and using non-atomic operations. The method further includes restricting the single owner thread from accessing the work queue using atomic instructions involving more than one access. The method also includes synchronizing amongst other threads with respect to their respective accesses to the work queue. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. National-Stage entry under 35 U.S.C. §371 based on International Application No. PCT/EP2008/002080, filed Mar. 14, 2008, which was published under PCT Article 21(2) and which claims priority to PCT Application No. PCT/EP2007/002511, filed Mar. 21, 2007, which are all hereby incorporated in their entirety by reference.
TECHNICAL FIELD
[0002] The present invention relates to a method and to apparatus for jointly controlling multiple devices, in particular for controlling various subsystem in a motor vehicle.
BACKGROUND
[0003] In recent years, a large variety of control subsystems for motor vehicles have been developed which assist the driver in different respects. A well-known type of control subsystem is an automatic brake control, which detects variations between rotating speeds of the wheels of a vehicle and controls braking force applied to the wheels so as to prevent these from slipping. Another prior art control subsystem known as ESP, electronic stability program, detects a steering wheel angle corresponding to a track curvature desired by the driver, compares it to an actual track curvature and, in case of a substantial discrepancy, brakes certain wheels in order to have the vehicle follow the desired track. Another control subsystem may adapt the damping efficiency of the vehicle suspension to the driving situation, so that, for example, the vehicle occupants may experience a feeling of cruising gently while driving at high speed on a smooth, straight lane, while providing a more direct feedback to the driver while driving, for example, off road.
[0004] In order to provide a comfortable driving experience, and, most of all, to enable safe driving, operating states of these various control subsystems must be adapted to each other. If instructions to switch over from one state to another are sent successively to the various subsystems, the subsystems may temporarily be in a combination of states which is ill-adapted to the current driving situation. In order to avoid such a situation, one might consider sending to each subsystem an instruction specifying not only the state which the subsystem is to assume but also a delay after which the changeover to the specified state is to happen, so that instructions may be sent to the subsystems one after the other, but once all instructions have been sent, the changeover can be carried out at the same time in all subsystems. However, for such a scheme to work, the delay must at least be long enough to allow instructions to be sent to each subsystem. Accordingly, there may be a considerable delay between the instant in which a new combination of states for the control subsystems is decided and the instant in which the control subsystems indeed switched over to the new states. This delay is the longer the higher the number of subsystems is, so that it is extremely difficult to integrate new subsystems on an existing platform. Further, the length of the delay must be known before the first instruction is transmitted to a subsystem.
[0005] At least one object of the present invention is, therefore, to provide a method and apparatus for jointly controlling a plurality of devices which allow to send instructions specific to each of the said devices simultaneously to all of these devices. In addition, other objects, desirable features, and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.
SUMMARY
[0006] This object is achieved by a method, a vehicle control unit, a vehicle subcontrol unit, by a computer program product, and by a data carrier.
[0007] According to an embodiment of the invention, a plurality n, n being an integer greater than 1, of devices, in particular vehicle subcontrol units, connected to a same communication channel, each device D l , l=1, . . . , n being capable of assuming a number m l of states, comprises the steps of:
[0008] unambiguously assigning to each combination of states of said n devices an integer code number M, wherein
[0000]
M
∈
[
x
,
x
+
∏
l
=
1
n
m
l
[
,
[0000] x being an arbitrary number;
[0009] for a combination of states to be set in the devices, selecting the code number M assigned to said combination;
[0010] broadcasting said code number M to all devices D l , l=1, . . . , n via said communication channel;
[0011] decoding, in each device, the state to be set in that device from said code number M; and
[0012] setting the decoded state in each device.
[0013] Since the total number of possible combinations is
[0000]
∏
l
=
1
n
m
l
,
[0000] the fact that M is in the interval
[0000]
[
x
,
x
+
∏
l
=
1
n
m
l
[
[0000] implies that each integer in
[0000]
[
x
,
x
+
∏
l
=
1
n
m
l
[
[0000] has a combination of states unambiguously assigned to it.
[0014] The number of states supported by each device is arbitrary, in particular there may be at least one device, the number of states of which is divisible by a prime number larger than 2.
[0015] According to a preferred embodiment, the m 1 states of each device D l , l=1, . . . , n are assigned integer indices S l,j =y l ,y 1 +1, . . . , y l +m l −1, wherein y l is an arbitrary integer, preferably 0 or 1, and in step a), each combination of states {S 1,j1 , S 2,j2 , . . . , S n,jn } is assigned a code number
[0000]
M
=
x
+
S
n
,
jn
-
y
n
+
∑
l
=
1
n
-
1
(
S
l
,
jl
-
y
l
)
∏
j
=
1
+
l
n
m
j
.
(
1
)
[0016] This code number may conveniently be decoded in each device D l by calculating
[0000]
S
l
,
jl
=
y
l
+
I
+
∞
(
M
+
1
-
x
N
l
)
-
I
-
∞
(
M
-
x
N
l
m
l
)
m
l
-
1
,
(
2
)
[0000] where
I +∞ (a) is the integer nearest to a which is greater than or equal to a, I −∞ (a) is the integer nearest to a which is smaller than or equal to a, and
[0000]
N
l
=
{
∏
k
=
l
+
1
n
m
k
if
k
<
n
1
if
k
=
n
.
[0019] In this way, each device can find out the index of the state it is to assume independently from the other devices. Further, the method is easily adaptable to different versions of the devices supporting different numbers of states, since all a given device has to know about the other devices for correctly decoding the received code word M is the number of states supported by the devices.
[0020] By further providing an initialising step of transmitting to each device D l the state numbers of at least each other device D l , . . . , D l−1 , D l+1 , . . . , D n , it is possible to replace or modify individual devices; for ensuring a correct decoding of the code word, it is sufficient that the state number of a modified device is made known to the other devices.
[0021] This can be achieved quickly and simply by broadcasting the state numbers M n of all devices D l , . . . , D n .
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and.
[0023] FIG. 1 is a schematic diagram of a motor vehicle in which the present invention is implemented;
[0024] FIG. 2 is a flowchart of an embodiment of the method of the invention; and
[0025] FIG. 3 illustrates a specific example of carrying out the method.
DETAILED DESCRIPTION
[0026] The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background and summary or the following detailed description.
[0027] FIG. 1 is a schematic diagram of a motor vehicle illustrating in block form some components which are relevant to the present invention. It should be understood that these components are not necessarily essential to the invention, and that the invention may be applicable to other components that those shown, too.
[0028] A steering wheel 1 controls the steering angle of front wheels 2 of the motor vehicle by means of a power steering controller 3 . The power steering controller 3 has actors for turning the front wheels 2 in proportion to the angular position of steering wheel 1 , and actors for exercising on the steering wheel 1 , a counter-torque to a torque imposed by the driver. The power steering controller 3 supports a plurality of operating states which differ from each other by the degree of assistance provided to the driver, i.e., by the proportion between the force required for turning the front wheels 2 and the counter-torque experienced by the driver. The power steering controller 3 further has a so-called Active Front Steering functionality, i.e., it supports a number of states having different ratios between the angle by which the driver turns steering wheel 1 and the corresponding yaw angle of the front wheels 2 .
[0029] An accelerator pedal 4 controls the load of an engine 5 via an electronic engine controller 6 . Engine controller 6 supports a plurality of states which use different characteristics for controlling the motor load as a function of the accelerator pedal position. For example, there may be a “calm” state in which the load varies little with the pedal position, and there may be a “nervous” state in which the load varies strongly with the pedal position.
[0030] A transmission controller 7 controls a gearbox 8 based primarily on engine load and speed detected by sensors, not shown, at engine 5 . A gearshift lever 9 is connected to the transmission controller 7 , so as to enable the driver to choose between different states of the transmission controller 7 , which use different algorithms for selecting the gear ratio in gearbox 8 based on engine speed and load, or for overriding a gear ratio selected by transmission controller 7 .
[0031] The transmission controller 7 may also be adapted to switch over between a two-wheel drive state and a four-wheel drive state, either based on the input from the driver or automatically, based, for example, on driving speed.
[0032] Electronic brake controller 10 controls the reaction of brakes, not shown, provided at the vehicle wheels, to the driver pressing a brake pedal 13 . The brake controller 10 may implement conventional brake control schemes such as an anti-blocking system or an electronic stability program, and different states of the brake controller 10 may vary in the amount of wheel slippage permitted before the anti-blocking system or the ESP is activated.
[0033] A suspension controller, not shown, is provided for controlling the stiffness of the vehicle's wheel suspension, different states of the suspension controller corresponding to different degrees of rigidity it imposes upon shock absorbers of the wheels.
[0034] All these controllers 3 , 6 , 7 , 10 are connected as sub-controllers or slave controllers to a master controller 11 by a bus system 12 .
[0035] The bus system 12 may have a linear structure in which all controllers are connected in parallel to a same bus line and data transmitted on the bus by one of the controllers are received in parallel by all others.
[0036] In FIG. 1 , the bus system 12 is shown to have an annular structure with bus segments extending from master controller 11 to engine controller 6 , from engine controller 6 to transmission controller 7 , and so on, and finally, from brake controller 10 back to master controller 11 . In such a bus system, the master controller 11 can judge that data sent by it were received correctly by all other controllers, if these data, after making a complete turn on the bus system 12 , are received uncorrupted at the master controller 11 again.
[0037] The task of the master controller 11 is to coordinate the various states the sub-controllers 3 , 6 , 7 , 10 can assume based on direct input from the driver, on his driving behaviour, road conditions, or the like. Since not all possible combinations of states of the various sub-controllers ensure a harmonic driving behaviour of the vehicle, it may be necessary to change the states of several controllers simultaneously. An operating method of master controller 11 and an arbitrary one of sub-controllers 3 , 6 , 7 , 10 by which this goal is achieved is described referring to the flowchart of FIG. 2 . The method may be implemented by appropriately programming data processing devices which embody the various controllers 3 , 6 , 7 , 10 , 11 .
[0038] In FIG. 2 , it is assumed that the number of sub-controllers D l is n, and that each sub-controller D l supports a plurality m l , l=1, . . . , n of states. In an initialising step m 1 , the master controller 11 broadcasts the complete set of state numbers m l , . . . , m n to all sub-controllers. Each sub-controller, in step s 1 , receives the set of state numbers m l , . . . , m n and records these in a local memory.
[0039] The initialising steps m 1 , s 1 can be carried out whenever the engine is started, or only if modifications to the control system have been carried out, which might have modified the state number m l , . . . , m n of any of the sub-controllers or the total number n of the sub-controllers. The total number n may also be broadcast in step m 1 , but this is not compulsory, since the sub-controllers can tell the number n by counting the state numbers m l , . . . , m n received.
[0040] The master controller then broadcasts a code number M in step m 2 . The term “broadcast” is used here to specify that although the bus system 12 is capable of transmitting data accompanied by an address so that they will be taken account of only by the controller to which they are addressed, broadcast data are received and taken account of by all sub-controllers, so that these data need not to be transmitted more than once.
[0041] At this time, the code number M can be a default code number specifying a set of states of the sub-controllers which is appropriate for low speed driving and accelerating. Alternatively, it might specify the states in which the sub-controllers were before turning off the engine 5 . The master controller 11 then, in step m 3 , observes for a certain time the behaviour of the driver, for example, the frequency and intensity of accelerating and/or braking, road conditions (e.g., roughness, slipperiness etc.), and based on these observations, decides in step m 4 on a combination of states S 1,j1 , . . . , S n,jn , of the various sub-controllers which is suited to the driver's requirements and to the road conditions.
[0042] Each of these states has an integer index associated to it, which will be referred to here by S l,jl , l=1, . . . , n, too. For the sake of convenience, it will be assumed that these indices can take integer values 0, 1, . . . , m l −1. In that case, a code number M is calculated in step m 5 for the selected combination of states based on the following formula:
[0000]
M
=
x
+
S
n
,
jn
+
∑
l
=
1
n
-
1
S
l
,
nl
∏
j
=
1
n
-
l
m
j
[0043] It should be noted here that the indices assigned to the states of device D l might as well begin not with 0 but with an arbitrary integer y l , l=1, . . . , n. In that case, a code number can be calculated according to the formula:
[0000]
M
=
x
+
(
S
n
,
jn
-
y
n
)
+
∑
l
=
1
n
-
1
(
S
l
,
nl
-
y
l
)
∏
j
=
1
n
-
l
m
j
[0044] What is important is that for the lowest numbered index S l,nl , the term (S l,nl −y l ) is 0, in order to ensure that the possible combinations of states of the various sub-controllers are assigned to consecutive integer numbers M.
[0045] After calculating the code number M, the method returns to step m 2 , and the code number M is broadcast to the sub-controllers.
[0046] Decoding of the code number M in each of the sub-controllers is carried out in step S 2 according to the formula
[0000]
S
l
,
jl
=
y
l
+
I
+
∞
(
M
+
1
-
x
N
l
)
-
I
-
∞
(
M
-
x
N
l
m
l
)
m
l
-
1
,
(
2
)
[0000] where
I +∞ (a) is the integer nearest to a which is greater than or equal to a, I −∞ (a) is the integer nearest to a which is smaller than or equal to a, and
[0000]
N
l
=
{
∏
k
=
l
+
1
n
m
k
if
l
<
n
1
if
l
=
n
.
[0000] In the case of x=y l =1 for all l=1, . . . , n, eq. (2) reduces to
[0000]
S
l
,
jl
=
I
+
∞
(
M
N
l
)
-
I
-
∞
(
M
-
1
N
l
m
l
)
m
l
(
3
)
[0049] Although all sub-controllers use the same decoding formula (2) or (3), the result of the decoding is specific to each sub-controller and depends on the number 1 assigned to it. Since these numbers need not change in the lifetime of the vehicle, they can be wired in each of the sub-controllers.
[0050] Equivalently, decoding may be carried out using the formula
[0000]
S
l
,
jl
=
y
l
+
I
-
∞
(
M
-
x
N
l
)
mod
m
l
(
4
)
[0000] Or, in case of x=y l =0,
[0000]
S
l
,
jl
=
I
-
∞
(
M
N
l
)
mod
m
l
,
(
5
)
[0000] wherein mod denotes the modulo operator, i.e. a mod b is the remainder of an integer division of a by b.
[0051] A further equivalent way of decoding is to use the formula
[0000]
S
l
,
jl
=
y
l
+
I
-
∞
(
M
-
x
N
l
)
-
I
-
∞
(
M
-
x
N
l
m
l
)
m
l
-
1
,
(
6
)
[0000] which, for x=y l =0, reduces to
[0000]
S
l
,
jl
=
I
-
∞
(
M
N
l
)
-
I
-
∞
(
M
N
l
m
l
)
m
l
(
7
)
[0052] A numerical example of the encoding and decoding procedure is given referring to FIG. 3 . For example it is assumed that three sub-controllers D 1 , D 2 , D 3 exist, supporting m 1 =4, m 2 =3 and m 3 =4 states, respectively. If arbitrary constants x, y l are set to 1, selecting states S 1 =1, S 2 =3 and S 3 =2 gives a code number M=10.
[0053] In the sub-controllers, divisors, N 1 =12, N 4 =4, N 3 =1 are calculated. Since for l>1, N l depends on the number of states supported by sub-controllers D k , k≠l, N l is not wired, so that it can easily be updated in all sub-controllers if the number of states of one of the sub-controllers is changed.
[0054] Based on these different divisors, sub-controller D l calculates S 1 =0, D 2 calculates S 2 =2, and D 3 calculates S 3 =1. In this way, each sub-controller derives from the same code number M the state which it is to assume. Since the code number M is available at the same time at all sub-controllers, switching of their respective states in step s 3 is easily synchronized.
[0055] While at least one exemplary embodiment has been presented in the foregoing summary and detailed description, 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 in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, 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 as set forth in the appended claims and their legal equivalents. | A method is provided for jointly controlling a plurality n, n being an integer greater than 1, of devices connected to a same communication channel, each of said devices D l , l=1, . . . , n, being capable of assuming a number m l of states. The method includes, but is not limited to unambiguously assigning to each combination of states of said n devices an integer code number M, wherein
M
∈
[
x
,
x
+
∏
l
=
1
n
m
l
[
,
x being an arbitrary number, for a combination of states to be set in the devices, selecting the code number M assigned to said combination (m 5 ), roadcasting (m 2 ) said code number M to all devices D l , l=1, . . . , n via said communication channel;decoding (s 2 ), in each device, the state to be set in that device from said code number M; setting (s 3 ) the decoded state in each device. | 6 |
TECHNICAL FIELD
The invention relates to a unit for adsorbing gases and odor from the ambient atmosphere utilizing a container or canister filled with molecular beads constituting a molecular sieve, and more particularly to such a unit wherein the container and molecular sieve bed therein have a passage extending therethrough, through which the ambient atmosphere is directed, the passage being defined by a foraminous wall through which the bed is exposed to the atmosphere.
BACKGROUND ART
It is well known that a bed of molecular beads (constituting a molecular sieve) in a container will adsorb gases and odors from air forced through the container and the molecular sieve bed. The gases and odors are pulled down inside the minute pores of the molecular beads. The gas and odor molecules have a critical diameter rated from two to ten angstroms. By selecting an appropriate molecular sieve (for instance a three A, four A, five A, or ten A molecular sieve, or a mixture of such molecular sieves), different undesirable gases and odors can be adsorbed.
A problem arises when forcing air through a molecular sieve bed to remove gases and odors. This problem is based on the fact that the molecular beads of the bed also have an affinity for moisture. Moisture in the air being filtered will first collect on the surfaces of the beads, and will thereafter work its way into the bead pores. Moisture in the bead pores reduces the amount of gases and odors that can be drawn into the pores and therefore reduces the working life of the molecular sieve.
The present invention is based upon the discovery that, if a central passage is provided through the molecular sieve bed and its container, and if the passage is defined by at least one foraminous wall exposing the molecular sieve bed to air flowing through the passage, gases and odors from the flowing air will be drawn into the pores of the molecular sieve, with far less moisture being adsorbed by the molecular sieve than when the air to be filtered is passed directly through the molecular sieve bed. Since the bulk of the moisture in the air to be filtered flows on through the passage, the working life of the molecular sieve, for the removal of gases and odors, is markedly increased.
While good results are achieved in a static version of the unit wherein the air flows through the passage by the flue effect, for more rapid and efficient gas and odor removal, it is preferred to draw the air through the passage by means of a fan.
The passage may be open, or it may be filled with polyester, fiberglass, or baffle means to slow down or diffuse the air to allow and encourage the small gas and odor molecules to sort of "sling off" toward the openings in the foraminous wall of the passage.
An indicator material may be mixed in the molecular sieve which will change color when the adsorbing property of the molecular sieve has been spent, and the bed needs replacement. Under these circumstances, the container for the bed should be transparent so that the indicator can be viewed.
DISCLOSURE OF THE INVENTION
According to the invention, there is provided an improved gas and odor adsorbing unit for the removal of unwanted gases and odor from the ambient atmosphere. The unit comprises a container or canister having a bed of particulate odor and gas adsorbing molecular beads therein, constituting a molecular sieve. The molecular sieve bed and its container are provided with a tubular passage defined by a perforated peripheral wall adjacent the bed. The bed is fully enclosed except for the perforated tube wall. Air containing moisture, gases and odors is drawn through the tubular passage. The molecular sieve bed has an affinity for gases, odors and moisture in the air drawn through the passage. However, by drawing the air through the passage, rather than directly through the molecular sieve bed itself, more gases and odors and less moisture will be adsorbed by the bed, thus markedly increasing the working life of the bed.
This effect may be further improved if the passage is provided with diffuser material such as baffles, polyester, or fiberglass, to slow down and disperse the air passing therethrough.
The molecular sieve preferably contains indicator particles which change color when the adsorbing properties of the molecular sieve are spent. It is therefore desirable to provide a container for the molecular sieve made of transparent material, allowing visual inspection of the bed and replacement thereof when the indicator particles have changed color.
While the ambient air may be drawn through the passage of the unit by the flue effect, it is preferable that a small fan be provided in the unit for this purpose. This enables more rapid and efficient pickup of gases and odors, although the molecular sieve will be spent more rapidly.
The molecular sieve will be chosen for its pore sizes, depending upon the diameter of the gas and odor molecules to be adsorbed.
The gas and odor adsorbing unit of the present invention can be made as a portable unit to be carried on the person of the user.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an exemplary embodiment of a gas and odor adsorbing unit of the present invention.
FIG. 2 is a plan view of the unit of FIG. 1.
FIG. 3 is an elevational view of the unit of FIG. 1.
FIG. 4 is a cross-sectional view taken along section line 4--4 of FIG. 3.
FIG. 5 is a bottom view of the unit of FIG. 1.
FIG. 6 is a perspective view of another embodiment of the present invention.
FIG. 7 is a fagmentary cross sectional view of the upper portion of the unit of FIG. 6.
FIG. 8 is a fragmentary cross sectional view of the bottom portion of the unit of FIG. 6.
FIG. 9 is a fragmentary perspective view of yet another embodiment of the present invention.
FIG. 10 is a side elevational view, partly in cross section, of a portable embodiment of the present invention mounted on the user.
DETAILED DESCRIPTION OF THE INVENTION
In order to describe the nature of the invention, reference is made to FIGS. 1-5 wherein an exemplary embodiment of the present invention is illustrated. The unit of FIGS. 1-5 is generally indicated at 1 and is a table-top unit.
Unit 1 comprises a canister 2 and a base member 3. The canister 2 is best seen in FIGS. 1 and 4. Canister 2 comprises a main body portion 4 and a removable bottom 5. While the shape of canister 2 does not constitute a limitation of the present invention, for purposes of an exemplary showing, the main body portion 4 is illustrated as comprising a sidewall 4a of circular cross-section and a substantially planar top 4b. The top 4b may constitute an integral one-piece part of sidewall 4a. Sidewall 4a may have a slight upward and inward taper, if desired. The main body portion 4 is preferably made of transparent glass or transparent plastic.
The bottom end of main body portion 4 is open and is closable by removable bottom 5. To this end, sidewall 4a, near its lower end, is provided with a series of external threads 6. The substantially planar removable bottom 5 is provided with an upstanding peripheral flange 7 which is internally threaded as at 8. The threads 6 and 8 cooperate to removably attach bottom 5 to canister main body portion 4. It would be within the scope of the invention to substitute a snap fit engagement between the cannister bottom 5 and side wall 4a, instead of the above described threaded engagement. The bottom 5 is completed by the provision of an upstanding annular flange 9 on its inside surface and a plurality of perforations 10 extending through the bottom and located within the confines of annular flange 9. The purposes of annular flange 9 and perforations 10 will be described hereinafter.
The top portion 4b of canister 2 has a central opening 11 formed therein. On its inside surface, the top portion 4b has a downwardly depending, annular flange 12 which surrouhds the opening 11. The annular flange 12 has a groove 13 formed therein. The groove 13 is adapted to receive the upper end of a tubular member 14. The lower end of tubular member 14 is just nicely received within the confines of annular flange 9 of removable bottom 5.
The inside surface of annular flange 12 is threaded as at 12a. The threads 12a are adapted to cooperate with threads 15 formed on the exterior surface of a downwardly depending annular flange 16 constituting an integral, one-piece part of a cap 17. The cap 17 may be provided with an upstanding rib 18 by which it can be rotated for engagement and disengagement with the threads 12a. It will be noted that cap 17 is provided with a plurality of perforations 19, similar to perforations 10 in removable bottom 5. The purpose of perforations 19 will be apparent hereinafter.
The tubular member 14 is illustrated in FIGS. 1 and 4 as being cylindrical with a circular cross-section. While this is a preferred configuration, the tubular member 14 may have any appropriate cross-sectional configuration. The tubular member 14 is defined by a foraminous wall 20, the perforations of which are most clearly shown at 21 in FIG. 1. Tubular member 14 may be made of perforated metal, plastic, cardboard, paper or the like. The tubular member 14 may also be made of screen material.
The holes 21 in tubular member 14 Preferably have a diameter of about 0.04 inch and the number of holes is such that at least half the surface of wall 20 is open.
The annular chamber defined by canister wall portion 4a, top portion 4b, tubular member 14 and removable bottom 5 is filled with molecular beads constituting a molecular sieve bed 22.
Since the gas and odor molecules to be removed from the ambient air will normally have a diameter falling within the range of 2 to 10 angstroms, the molecular sieve should be chosen to have beads with comparable pore sizes. Exemplary, but non-limiting molecular sieve beds are made of sodium or calcium aluminosilicate and are available in pore sizes of 2 angstroms, 3 angstroms, and up to 10 angstroms.
It is preferred that the molecular sieve bed 22 be of the general type taught in U.S. Pat. No. 3,705,480. In this patent it is taught that the molecular particles of the molecular sieve bed may have interspersed therein particles of a dew point indicating material. An exemplary, but non-limiting example of such dew point indicating material is silica gel coated with cobalt chloride. The dew point indicating particles or beads change color from blue to pink progressively, as the particles gradually attract and entrap moisture. Preferably, the blue gel indicator particles are interspersed indiscriminately or at random throughout the mass or bed of particles constituting the molecular sieve. The blue gel particles may constitute about 20% of the bed by volume. When distributed at random in the molecular sieve bed 22, the color change dew point indicating material furnishes a progressively continuous indication of the moisture content of the molecular sieve bed 22, until a point is reached wherein the bed 22 is considered to be spent, and requires replacement. It is for this reason that the main body portion 4 of canister 2 is preferably made of transparent material, so that the color change dew point indicating material can be observed.
Returning to FIG. 4, it will be apparent that the tubular member 14 defines a passage 23 through the molecular sieve bed 22. The passage 23 is connected to ambient atmosphere through perforations 10 in removable bottom 5 and perforations 19 in cap 17. Furthermore, the molecular sieve bed 22 is exposed to ambient atmosphere only at foraminous wall 20 of tubular member 14. The canister 2 may be designed and made to be disposable when the molecular sieve bed 22 therein is spent. Alternatively, the bottom 5 may be removed from canister 2 and the spent molecular sieve bed 22 is replaced by a fresh molecular sieve bed.
The embodiment of FIGS. 1-5 is intended to have ambient air forced through passage 23 by means of an electric fan unit, generally indicated at 24. The precise nature of fan unit 24 does not constitute a limitation of the present invention. Any appropriate, commercially available fan can be used. It has been found that excellent results are achieved using a fan having the capacity of moving from about 2 to about 5 cubic feet of air per minute.
In the embodiment of FIGS. 1-6, the canister is mounted upon a base member, generally indicated at 3. While base member 3 may have any appropriate configuration and may be made of any appropriate material, for purposes of an exemplary showing it is illustrated as being molded of plastic with a substantially planar top 26 and planar sides 27 through 30. Each of the sides 27 through 30 is provided with a notch in its lower edge, as indicated at 27a through 30a, respectively. Notches 27a through 30a permit circulation of air within base 3.
The base top 26 is provided with a downwardly depending annular wall portion 31 terminating in an annular shoulder 32. The annular shoulder 32, in turn, terminates in a downwardly depending wall 33 which defines a circular opening 34 in the base top 26. The annular wall 31 and shoulder 32 are so sized as to just nicely receive the removable bottom 5 of canister 2, as is shown in FIGS. 1 and 4.
The underside of shoulder 32 carries a series of four downwardly depending lugs 35, each provided with a threaded bore 36. The threaded bores 36 of the four lugs 35 are adapted to receive mounting bolts 37, by which the electric fan unit 24 is affixed to base 3. The mounting bolts 37 also support a bottom plate 38 for base 3. The bottom plate 38 is provided with a large central opening 39 exposing the majority of fan unit 24.
In the embodiment illustrated, the fan unit 24 is adapted to draw air through perforations 19 in cap 17, passage 23, perforations 10 in removable canister bottom 5 and into the interior of base 25. The fan unit 24 returns this air to the exterior of the unit through the notches 28a through 30a of the base. It will be understood by one skilled in the art that it is within the scope of the invention to provide a fan unit which will circulate the air in the opposite direction to that just described. The electric fan unit 24 is connected to a source of current by lines 40 and 41, fragmentarily shown in FIGS. 1, 2, 4 and 5. Lines 40 and 41 may terminate in a conventional plug to be engaged in a wall outlet or the like. One of the lines 40 and 41 will contain an on-off switch. Such a switch is shown at 42 in FIGS. 1-5, in the form of a conventional push button switch. It would be within the scope of the invention to substitute a timer switch, such as a dial type manual-set timer switch, for switch 42.
The embodiment of FIGS. 1-5 having been described in detail, its operation can now be set forth. As indicated above, the molecular sieve bed 22 has an affinity for gases, odors and moisture. If ambient air to be filtered is simply drawn through the molecular sieve bed directly, it has been found that moisture will collect on the surfaces of the molecular sieve beads and ultimately will penetrate the pores of the beads, reducing the number of gas and odor molecules which can be trapped in the pores of the molecular sieve beads. It has been discovered, however, that with the provision of passage 23 through the molecular sieve bed 22, less moisture and more gas and odor molecules are adsorbed by the bed. This greatly increases the working life of the molecular sieve bed 22 from the standpoint of adsorption of gases and odors.
Since some moisture adsorption is unavoidable, the color change dew point indicating material within the bed will still serve as an adequate visual indication of when the bed is spent. Since the molecular sieve bed 22 is exposed to only that portion of the ambient air being drawn through passage 23, by virtue of foraminous wall 20, bed saturation will occur adjacent foraminous wall 20 first, and thereafter will work its way slowly toward canister wall portion 4a. Thus, when the color change dew point indicating beads adjacent canister wall portion 4a change from blue to pink, this is a good indication that the entire bed 22 is saturated and should be replaced.
Under some circumstances, the location of diffusing means in the passage 23 will slow down and disperse the air being drawn therethrough, increasing the chances of the small gas or odor molecules passing through the perforations in passage wall 20 and into the molecular sieve bed 22. Polyester or fiberglass filter material, can be used for this purpose. The use of baffles within passage 23 will also serve this purpose. The amount of air flowing through passage 23 can also be controlled by properly sizing perforations 19 and 10.
The size of the unit 1 and its molecular sieve bed can be varied, according to the size of the room or space, the ambient air of which is to be filtered.
It has been found that adequate filtering can be achieved in a typical room when the canister is sized to contain about one quart of molecular sieve bed particles per 400 square feet of floor space. A molecular sieve bed, so sized, will remain effective for about 1 and 1/2 weeks with the electric fan assembly 24 running.
It has further been found that when the fan unit 24 is turned off, the unit 1 will continue to operate as a static gas and odor adsorber, the molecular sieve bed continuing to attract gas and lingering odor molecules from the ambient air. The ambient air will tend to move upwardly through passage 23 by virtue of the flue effect. Under these circumstances, adsorption is slower, but the effectiveness of the molecular sieve bed will last some ten times longer.
If the ambient air is filled with foreign material, or in order to retain a diffusing medium within passage 23, it is sometimes desirable to locate a disk of filter paper at one or both ends of passage 23. For such purposes, a 50 micron particle filter has been found adequate.
When a filter sheet is to be located at the upper end of passage 23, a properly cut filter disk 43 (see FIG. 4) can be located on and supported by an annular lip 44 formed on the annular lug 12. If a similar filter disk is to be located at the bottom of passage 23, it can simply be laid upon that portion of the inside surface of removable bottom 5 located within the confines of tubular wall 20.
The embodiment of FIGS. 1-5 is a dynamic embodiment, in that the fan unit 24 causes air to pass through passage 23. As indicated above, even when the fan unit 24 is turned off, the unit 1 will continue to function as a gas and odor adsorber in a static fashion, i.e., without mechanically induced air movement. Adsorption of gases and odors, under these circumstances, is slower. Nevertheless, the provision of a passage through the molecular sieve bed continues to reduce moisture pickup, thus extending the working life of the bed with respect to adsorption of gases and odors.
Reference is now made to FIGS. 6, 7, and 8, wherein a static adsorber, involving the principles of the present invention, is shown. The adsorber is generally indicated at 45. The adsorber comprises a vessel or canister 46, preferably made of transparent glass or plastic. While not required, the canister is illustrated as being of cylindrical configuration and having a neck portion 47 of lesser diameter, so as to form an annular shoulder 48. The exterior surface of neck portion 47 is threaded.
A cap 49 is provided, having a substantially planar upper surface 50 and a downwardly depending skirt portion 51. The inside surface of skirt portion 51 is threaded so as to cooperate with the threads of the neck portion 47 of the canister, with the result that the cap 49 is removably affixable to the canister 46. The assembly may be provided with a mounting bracket 52. The mounting bracket 52 has a circular opening 53 formed therein, so as to just nicely receive the neck portion 47 of canister 46. When the cap 49 is affixed to canister 46, the mounting bracket 52 is trapped between the canister shoulder 48 and the bottom edge of the downwardly depending skirt 51 of cap 49.
The adsorber 45 of FIGS. 6-8 is provided with a foraminous tubular member 54 similar to the foraminous tubular member 14 of the embodiment of FIGS. 1-5. As is shown in FIG. 8, the bottom of canister 46 may be provided with a central perforation 55 through which the end of foraminous tubular member 54 extends. The amount by which the foraminous tubular member 54 extends through perforation 55 is determined by an annular rib 56 formed on the tubular member 54 which abuts the bottom of canister 46. The upper end of tubular member 54 is engaged within an annular rib 57 formed on the inside surface of cap 49. A plurality of holes 58 are formed in the cap 49 within the area encircled by annular rib 57. Thus, it will be apparent that tubular member 54 is open to the ambient atmosphere at both of its ends.
The tubular member 54 may be made of any of the materials and in any of the ways described with respect to tubular member 14 of FIG. 4. The tubular member 54 is surrounded by a molecular sieve bed which may be identical to bed 22 of FIG. 4 and preferably contains the color change dew point indicating beads as described above. If desired, the tubular member 54 may be provided with diffusion means of the same type and in the same manner described above. One or both ends of tubular member 54 may be provided with a filter paper disk (not shown), as described above. Such a disk at the upper end of tubular member 54 can simply be trapped and held between the upper end of the tubular member and the adjacent portion of cap 49. At the lower end of tubular member 54, some appropriate form of retaining means (not shown) would have to be provided for the filter disk, as for example, a cap similar to cap 17 of FIG. 4. Alternatively, both ends of the tubular member could be open. For example, a single large opening could be substituted for the openings 58 in cap 45.
The operation of the embodiment of FIGS. 6-8 is identical to that described with respect to the embodiment of FIGS. 1-5 with the exception that the embodiment of FIGS. 6-8 relies solely on the flue effect for movement of ambient air through tubular member 54. It will be understood that adsorption of gases and odors will be slower with the unit of FIGS. 6-8 but the working life of the molecular sieve bed will be considerably longer than with a dynamic unit.
Yet another embodiment of the present invention is illustrated in FIG. 9. In FIG. 9, the adsorber unit is generally indicated at 59. The adsorber unit 59 comprises a rectangular canister having a top 60, a bottom 61, sides 62 and 63 and ends 64 and 65. In this embodiment both the top 60 and the bottom 61 are removable members.
The entire canister may be made of transparent plastic material or the like. It is desirable that at least sides 62 and 63 be made of transparent material since the unit will use the same type of molecular sieve bed described with respect to the previous embodiments, having a quantity of color change dew point indicating material mixed therein. The molecular sieve bed completely fills the canister. By making at least sides 62 and 63 of transparent material, the molecular sieve bed can be visually inspected to determine when it has become saturated and requires replacement.
The unit 59 is located between and is affixed end-to-end to segments 66 and 67 (shown in broken lines) of a heating and/or air conditioning duct. The unit 59 has a plurality of foraminous tubular members extending from end 64 through end 65 of unit 59. The number of foraminous tubular members does not constitute a limitation of the present invention. For purposes of clarity, two foraminous tubular members are shown in broken lines at 68 and 69. While the tubular members 68 and 69 may be rectalinear in configuration, they can also be of sinuous configuration, as shown in FIG. 9. This enables the unit 59 to be shorter from end wall 64 to end wall 65. Again, the foraminous tubular member 68 and 69 can be made of the same materials and in the same manner decribed with respect to the embodiment of FIGS. 1-6. Diffuser means may also be located within the tubular members, if desired.
It will be evident that this is a dynamic application of the adsorber of the present invention. In this instance, movement of air through the unit 59 and in the direction of arrow A is caused by the furnace fan. Use of the embodiment of FIG. 9 could be most advantageous to those suffering from allergies and the like.
When the blue indicator beads of the molecular sieve bed, located near sidewalls 62 and 63, turn from blue to pink, it is evident that the molecular sieve bed is saturated and should be replaced. By removal of bottom 61, the old bed can be discharged from unit 59. Thereafter, the bottom 61 is replaced and the top 60 is removed so that the unit 59 can be filled with a fresh molecular sieve bed.
Again, it will be appreciated that the provision of foraminous tubular members 68 and 69 will provide the same advantage found in the embodiments of FIGS. 1-8. Most of the moisture in the air passing through duct 66/67 will remain in the moving air, while gases and odors will be removed by the molecular sieve bed.
It would be within the scope of the invention to so size unit 59 that it could be removably located within a furnace and/or air conditioning duct, substantially filling the cross section of the duct. To replace the molecular sieve bed, the unit 59 would be removed from the duct by means of a door or removable panel in the duct.
Reference is now made to FIG. 10, wherein a portable version of the gas and odor adsorbing unit of the present invention is illustrated. The unit is generally indicated at 70, and is affixed to the body of the user 71 in any appropriate manner, as for example, by adjustable straps 72 and 73.
The unit 70 comprises an upper housing portion 74 and a lower cannister portion 75. The cannister portion 75 can be similar to that illustrated in FIGS. 1 through 6. Cannister portion 75 comprises a side wall 76, a top 77 and a bottom 78. A foraminous tubular member 79 defines an air passage 80 through the cannister portion. A molecular sieve bed 81 fills the space between tubular member 79, side wall 76, top 77 and bottom 78. Again, the molecular sieve bed may contain color change dew point indicating beads, as described above. When this is the case, the cannister portion 75 is preferably made of transparent plastic or the like. The upper and lower ends of tubular member 79 may be open, or they may be provided with cover members (not shown) provided with perforations. Such cover members may be provided to retain diffusion means within tubular member 79, or to determine the amount of air passing through tubular member 79, if desired. The tubular member 79 could also be provided with baffle means, as described with respect to FIGS. 1 through 6.
The cannister portion 76 is detachably affixed to the bottom of housing portion 74 in any appropriate way including clamp means, a threaded engagement, a snap fit, or the like.
The housing portion 74 contains a small electric fan unit, generally indicated at 82. The electric fan unit 82 may be powered by any appropriate power source 82a such as batteries or a rechargeable power source.
The upper end of housing portion 74 is provided with an opening 83 to which a duct member 84 is connected. In this way, air drawn through the cannister portion 76 by fan unit 82 is directed toward the nose and mouth of the user 71.
The unit 70 could be advantageously employed by one working in adverse atmospheric conditions, or one suffering from respiratory problems or allergies. The duct 84 is preferably made flexible and adjustable. Alternatively, the duct 84 could be replaced by a face mask. While the unit 70 is shown mounted on the user's chest, with appropriate modifications to the duct 84, or with the use of a face mask, the unit could be affixed to the user's back so as to be out of the way, if the user is required to perform various manipulations.
The positions of the housing portion 74 and cannister portion 76 could be reversed. In this instance the cannister portion would be located above the housing portion 74 and the duct 84 or face mask would be attached to the upper end of the cannister portion. Fan unit 82 would push air through tubular member 79, rather than draw air therethrough.
In all of the embodiments taught herein, a molecular sieve bed can be used which does not contain color change dew point indicating material. Under these circumstances, the cannister portion 76 need not be made of transparent material, and the molecular sieve bed should be replaced at predetermined intervals.
Modifications may be made in the invention without departing from the spirit of it. | An improved gas and odor absorbing unit. The unit comprises a container having a bed of particulate odor and gas absorbing material therein constituting a molecular sieve. A tubular passage extends through the container and bed and is provided with a perforated peripheral wall adjacent the bed. The bed is fully enclosed except at the perforated tube wall. Air containing moisture, gases and odors is directed through the tubular passage. The molecular sieve bed has an affinity for gases and odors and an affinity for moisture as well. By directing the air through the tubular passage, rather than directly through the bed itself, more of the gases and odord and less moisture will be absorbed by the bed, increasing the working life of the bed. This effect may be further improved if the tubular passage is provided with diffuser material such as baffles, polyester, or fiberglass to slow down and disperse the air passing therethrough. The molecular sieve bed preferably contains indicator particles which change color when the bed needs to be changed. To this end, the container is preferably transparent allowing visual inspection of the bed. The unit can be either static or dynamic, depending upon whether air is directed through the tubular passage by the flue effect or by fan means. | 1 |
STATEMENT OF INVENTION
This invention relates to electronic assemblies and more particularly to an assembly with edge connected modules.
BACKGROUND OF THE INVENTION
The trend in high performance computers is to use increasing numbers of processors operating common memory modules referred to sometimes as Basic Storage Modules (BSM). The coupling between these processors and common memory modules is by some form of network. The coupling can be tightly coupled or loosely coupled. IBM Corporation System/390™ 9000 Series (System/390 is a trademark of International Business Machines Corporation) family is an example of a tightly coupled multi-processor system. In a tightly coupled system the processors share real storage, are controlled by the same control program, and can communicate directly with each other. In a tightly coupled system there may be N processors and M BSMs. All processors have equal access to a BSM through some form of N×M switch, such as a cross-bar switch to select the path between a given processor and a currently addressed memory for storing and fetching data. In loosely coupled systems the processors share access to direct access storage and are coupled, for example, by channel to channel adapters for passing control information. This present invention is most suitable for tightly coupled applications.
The performance parameters of most importance to the system are the processor cycle time, bandwith, electrical path length, round trip delay and timing skew. The cycle time is minimized by placing the cycle determining path elements in the closest possible proximity to each other. The bandwidth between processor and memory is achieved by using the fastest data rate over a large number of parallel connections between processors and switches and between switches and BSMs. The electrical path length is the length between data latching points on different, but interconnected, functional units as measured in nanoseconds. The total round trip delay from a processor to a memory and back is known as the memory latency. The skew is the electrical path length differences due to variations in routing from one point to another.
Applicant's U.S. Pat. No. 5,058,053 shows one system for providing some of these parameters of importance in a system with unidirectional information flow through the memory modules. Applicant has other pending applications with plural memory modules, BSMs and request and response switches. They are: U.S. application Ser. No. 07/675,583 filed Mar. 26, 1991 entitled "High Performance Computer System Package" and U.S. application Ser. No. 07/675,243 filed Mar. 26, 1991 entitled "Integrated Circuit Chip Package Having Signal Input/Output Connections Located at Edges of the Substrate," now U.S. Pat. No. 5,168,347. These applications are incorporated herein by reference. This present invention provides shorter path lengths between processors and BSMs.
SUMMARY OF THE INVENTION
In accordance with one embodiment of the present invention a high density assembly includes a rack frame with orthogonal members. The frame has multiple pairs of slidable guide members, each pair in one given plane, and a plurality of flat packages are slidably mounted in said frame in the guide members. Each package includes power supply means and an edge connected module extending in said one given plane beyond the frame. The edge connected modules include a plurality of multicircuit semiconductor chips mounted on a carrier and having connection means along the edges. A planar circuit board extends perpendicular to said one given plane mounted forward of the frame juxtapositioned to said edge connected modules. The circuit board includes connectors facing the edge connected modules and coupled to the edge connection means along the edges. The circuit board has coupling means between opposite broad surfaces thereof to couple signal from one side of the board to the other via a network. A plurality of memory circuit cards having connectors along one of the edges are coupled to the circuit board on the surface opposite the side coupled to said edge connected modules.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric sketch illustrating the system according to the present invention with a support rack.
FIG. 1A illustrates a portion of the support rack.
FIG. 2 is an isometric sketch showing the front of the system according to the present invention with the support frame removed.
FIG. 3A is a front elevation functional sketch illustrating placement of system elements in a four-way cluster.
FIG. 3B is a front elevation of two identical four-way clusters tightly coupled.
FIG. 4 is a sketch of a package including an edge connected module in the system of FIGS. 1-3.
FIG. 5 is an exploded view of the edge connected module of FIG. 4.
FIG. 6 is a sketch of the power planes and wiring to couple the signals and power in the edge connected module of FIG. 5, and it illustrates the circuit board interconnections between the memory cards and the modules.
FIG. 7 illustrates the flex connector of FIG. 5.
FIG. 8 illustrates the insertion of the edge connected package into the PC
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 there is shown the support system 10 with a support frame 11 comprising orthogonal elements 11a, 11b and 11c extending in respective three XYZ directions. The support frame 11 includes support racks 13 fixed to vertical members 11b extending in the Y direction (see FIG. 1A). The racks 13 comprise channel support elements 13a fixed in the X direction or horizontal plane and in the Y-direction or vertical plane to the vertical members 11b, as shown in FIG. 1a. Planar packages 15 are slid into these racks 13. A power bus 17 extends parallel to the vertical support elements 11b in the Y direction that couples power via connectors 15c (see FIG. 4) to the packages 15 in the racks 13. Horizontal members 11a extend in the X direction and cross the vertical members 11b at top and bottom of the frame 11. Members 11c extend in the front to back or Z direction.
Referring to FIGS. 2, 3A and 3B, there is illustrated the system 10 without the frame 11. The planar packages 15 include a power supply section 15a joined to the power bus 17 to supply power to the power supply sections of the packages. The section 15a extends in the Z direction from the rear of the support frame 11 to cross support elements 16 of elements 11a as shown in FIG. 1. A pair of circuit boards 19 and 20 are mounted to these cross members 16 such that the boards extend in the YZ plane orthogonal to the front face of the frame 11. The packages 15 include edge connected modules (ECMs) 21 extending from the power supply sections 15b and when mounted in the frame 11 extend forward of the orthogonal members 16 in FIG. 1. The edge connected modules (ECM) 21 extend in the XZ plane between the circuit boards 19 and 20. These ECMs are each powered by the corresponding power supply in sections 15a and 15b of the same package 15. The ECMs, as the names imply, have edge connected input and output connectors 29 and 30 as shown in FIGS. 4 and 5. These edge connectors are coupled to one or both of the circuit boards 19 and 20 on the broad surfaces facing each other. The ECMs are fixed to the power supply sections 15a and 15b of the package 15 and the whole package 15 is slid in position from the rear in the Z direction so that the package 15 is supported in the channels 13a and the ECM is slid between ZIF (Zero Insertion Force) edge connectors 29 and 30 on the circuit cards 19 and 20. The module 21 includes the array of chips 21a, cooling plate 21b, an array interposer connector 21c, a high density board 21d, a power interposer connector 21e and power planes 21f. Referring to FIG. 6 there is a sketch showing how these elements are connected. The chip 102 is on the substrate 101. This combination forms the array 21a with the other chips. The cooling plate 21b is above the chip. The surface input/output pads 103 are on the surface of board 21d and these input/output pads are coupled to interposer wires in array interposer 21c and the substrate 101 has vias 101a coupling the array interposer wires 105 in interposer 21c to the chips 102. The power for the arrays is coupled via the power planes 21f through vias 105b to the power interposer wires 104a to the board 21d and via the board 21d vias 107a to the wires 105 of the array interposer connector and through vias 101a separate from the signal carrying vias to the chip 102. The ZIF film connectors 29 or 30 are shown in FIGS. 7 and may be like those shown and described in applicant's joint U.S. Pat. No. Re. 33,604 or U.S. Pat. No. 5,123,852, Ser. No. 07/702,258, filed May 17, 1991, entitled "Modular Electrical Connector". These patents are incorporated herein by reference. The flex-film connector couples to the PC board 19 or 20 and the board couples over the card connector to the memory card 25.
In FIG. 3A there is illustrated a four-way cluster with the processor ECMs (CPO-CP3) near the top and the switch module SCE-A 33 at the bottom. The interconnection wiring circuit board 20 couples to the memory cards 25, the processor modules CP0-CP3, switch module 33 and to connector 119 for connection to a second switch module. The switch module SCE-A also has connectors 33a for connection to a second memory card.
The ECMs as shown in FIG. 3B for two tightly coupled four-way clusters are stacked in the rack with two central ECMs 21 containing the SCE or switch control elements 33 (SCE-A and SCE-B) and the upper four and lower four ECMs 21 (CP0-CP7) containing the processor elements. In accordance with one embodiment of the present invention, these processor ECMs 21 contain a combination of scalar, vector and crypto type processor elements. The top most and bottom most ECMs 31 contain the memory power supplies. Memory cards 25 are mounted in the XY plane orthogonal to the printed boards 19 and 20 and have connectors along one edge to couple into the circuit boards 19 and 20 on the side opposite that of the edge connectors for the ECMs. The connectors 25a for the memory cards are adjacent to the center packages containing the SCE 33 ECMs.
The memory cards 25 are stacked in the Z direction as shown in FIG. 1. Either above or below these memory cards in the Y direction are the fans 27 to cool the memory cards, and if need be, additional memory power supplies. As shown in FIG. 4 a water manifold provides cooling water to the power supply sections of the packages 15 and the ECMs include a cooling plate 21b as shown in FIG. 5. The power planes in the ECM are coupled into the power supply portions. There are vias or feedthrough pins that carry the power from the power planes in the ECMs to the chips arrays. These vias and power planes are shown in copending application Ser. No. 07/675,243 and continuing application Ser. No. 07/873,530 filed Apr. 21, 1992. The frame 11 includes air chillers 110 (FIG. 1) extending in the XZ plane that are fixed to the front surface of the front vertical member 11b that direct air through the cards. The SCE can be request and response switches like that shown in FIGS. 3 and 5 in U.S. Pat. No. 5,058,053 of Gillett, incorporated herein by reference.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. | A high density computer interconnection assembly is provided by a plurality of flat packages slidably mounted along a rack in a frame in one given plane. The packages include edge connected processors and switch modules with associated power supply. One or two interconnection wiring circuit boards extend perpendicular to the one given plane and adjacent and along the edge of the edge connected modules to couple thereto whereby the interconnection circuit board couples said switch modules to said processor modules along one broad surface of said interconnection circuit board. Memory cards are coupled to the opposite broad surface of the interconnection circuit board. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention.
This invention relates to the field of stereophonic FM broadcasting, and more particularly to a method and circuitry for precluding or minimizing to a negligible level the degree of overshoot of a lowpass filter network beyond a predetermined signal excursion limit.
2. Description of the Prior Art.
A preliminary patentability search was conducted in the following classes and sub-classes with respect to the subject invention:
Class 307--sub-classes 543; 546; 547 and 556.
Class 328--sub-classes 169; 170; 171 and 175.
Class 330--sub-classes 126 and 151; and
Class 381--sub-classes 13; 14; 94 and 106
As a result of the search in this area, eight (8) U.S. patents as follows were found:
U.S. Pat. Nos. 3,651,339; 3,968,384; 3,986,049; 4,110,692; 4,103,243; 4,208,548; 4,241,266; 4,441,199.
In addition, three additional U.S. patents have come to my attention and have been considered, and are identified as U.S. Pat. Nos. 4,134,074; 4,383,229; and 4,460,871
Of the eight patents listed above that were found as a result of the search, none appear to be relevant with respect to the invention described herein. Of the three patents listed in the immediately preceeding paragraph, only U.S. Pat. Nos. 4,134,074 and 4,460,871 appear to have any pertinency.
U.S. Pat. No. 4,134,074 to Hershberger directly addresses the problem of lowpass filter overshoots in stereophonic FM broadcasting. However, the method and apparatus taught by Hershberger are different in structure and function from the method and apparatus forming the subject matter of the instant invention. In Hershberger, two nearly identical lowpass filters are placed in the signal path. The amplitude overshoots of the first filter are isolated from and recombined with the signal in such a way that they cancel not only the first filter overshoots, but predict and inhibit overshoots in the second filter as well. Thus, the Hershberger U.S. Pat. No. 4,134,074 circuit satisfies the requirement with full consideration to the bandwith and amplitude constraints, but at the expense of a second, otherwise redundant lowpass filter circuit. In addition, another disadvantage of the Hershberger circuit, is that it calls for a constant "group delay" characteristic in the second filter, no small matter in filters of the higher order, more complex designs common to FM broadcasting.
U.S. Pat. No. 4,460,871, issued approximately five and a half years after Hershberger U.S. Pat. No. 4,134,074, constitutes a refinement of the concept disclosed by Hershberger. In Orban's U.S. Pat. No. 4,460,871 circuit, the primary lowpass filter is permitted to overshoot in the expected manner. Overshoots are again isolated and reintroduced to the signal path in a manner which opposes and thus cancels the amplitude over excursions. Rather than pass the entire "corrected" signal through a second lowpass filter as is done in Hershberger, only the isolated overshoots are filtered before reintroduction. Thus, in addition to an otherwise redundant low-pass filter, Orban's U.S. Pat. No. 4,460,871 calls for signal equalization, a second "safety" clipper and a third, yet simple, lowpass filter element.
Thus, with respect to U.S. Pat. Nos. 4,134,074 and 4,460,871, each of these patents discloses at least one low-pass filter or other means of program bandwith restriction which, itself, exhibits normal amplitude overshoot characteristics.
Additionally, in each of these patents some means is required to isolate and control the amplitude overshoots of the first lowpass element, but at the expense of harmonic generation.
Still further, in each of these patents, a second low pass filter element is employed to suppress signal harmonics generated by overshoot correction circuitry.
Accordingly, one of the primary objects of the present invention is to eliminate much of the circuitry required by these patents and to provide overshoot protection by a much simpler circuit utilizing fewer components.
Still another object is the provision of an overshoot protection circuit which eliminates the need for multiple low-pass filter assemblies.
A still further object is the provision of a filter overshoot control circuitry that may be used with almost any variety of existing lowpass filter designs including those already in place in commercial broadcasting equipment.
Yet another object of the invention attendant to the factor of simplicity in design, is the provision of filter overshoot control circuitry which presents a more direct signal path to the audio program, lessening the chance for sonic degradation.
Since the filter overshoot control circuitry of this invention may be utilized with existing lowpass filter designs that are already in place in commercial broadcast equipment, another object of the invention is to lessen considerably the cost of implementing filter overshoot control circuitry in already in place commercial broadcast equipment.
The invention possesses other objects and features of advantage, some of which, with the foregoing, will be apparent from the following description and the drawings. It is to be understood however that the invention is not limited to the embodiment illustrated and described since it may be embodied in various forms within the scope of the appended claims.
SUMMARY OF THE INVENTION
In terms of broad inclusion, the filter overshoot control circuitry of the invention comprises a first clipping circuit which functions to establish input signal amplitude limits, cooperating with a phase-lag network which displaces high frequency signal components with respect to low frequency signal components, and a second clipping circuit to re-establish signal amplitude limits, with the output therefrom being fed into a comparator circuit which recovers those signal components lost in the second clipping process, and which feeds such signal components into combining circuitry to re-introduce recovered, clipped signal components from the second clipping operation back into the primary information signal, but in opposite phase.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the filter overshoot control circuitry.
FIG. 2 is a schematic diagram of the filter overshoot control circuitry.
FIG. 3 is a schematic diagram of a lowpass filter design typical of what might be encountered in broadcasting practice. This example 7-pole, elliptic-function active filter is derived from textbook formulas and no claim of novelty or patentable invention is made with respect thereto.
FIGS. 4(A), 4(B), 4(C), 4(D), 4(E) and 4(F) illustrate signal wave-forms at various circuit points.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The current or conventional system for stereophonic FM radio broadcasting used world-wide is believed to be one of frequency-division multiplexing. The stereophonic program consists of a "left" and a "right" channel of audio information. The left-plus-right "sum" signal modulates an audible-range "base band" which extends in frequency from a nominal 30 Hz to 15 kHz. The left-minus-right "difference" signal amplitude-modulates a suppressed-carrier "subcarrier" centered at 38 kHz, the resultant sidebands occupying the range of 23 kHz to 53 kHz. A "pilot" signal is inserted at 19 kHz, and additional subcarriers not related to the program signal may optionally be added above the upper sideband edge beyond 53 kHz. An analysis of the total "composite" signal shows that if the program audio signal contains frequency components above 15 kHz, these higher frequencies could interfere with the pilot and non-program subcarrier signals, or even cause the base band and lower sideband to "alias" or interfere with one another. To prevent these potential problems, sharp-cut off lowpass filters are customarily placed in the audio signal path to strictly limit the program frequency range to 15 kHz.
Common broadcasting practice also places a limit on the peak deviation, or modulation of the FM broadcast "carrier" frequency to guard against interference between stations. This translates directly to a limit placed on the peak amplitude of the modulating program audio signal in addition to the limit imposed on signal bandwith.
The two signal constraints are difficult to realize simultaneously. Even the most fastidious lowpass filter designs will invariably exhibit a certain degree of signal overshoot, due both to the naturally uneven phase response of the filter and to the filters normal and desired elimination of higher order frequency components which, themselves, help define the instantaneous signal peak amplitude. It is not uncommon for the comparatively steep filters used in FM broadcasting to deliver output amplitude excursions up to twice the value of an amplitude-limited input signal. Means to compensate for, or to negate lowpass filter amplitude overshoots, have thus been necessarily devised.
Some solutions which have been devised to cope with lowpass filter overshoots generally fall into the "brute" force category. Though they may meet the requirements in a literal sense, they are not without a performance tradeoff, usually resulting in audible degradation of the audio program signal.
In one instance, for example, a frequency-selective clipping circuit has been proposed. This circuit reduces the signal clipping threshold as the audio frequency increases. Overtones which are harmonically related to low frequency fundamentals are reduced to levels which cause no filter overshoots. However, high frequency fundamental signals which would not necessarily cause an overshoot problem in the first place are similarly limited. Not only is the high frequency performance of the system audibly degraded, but the unnecessary clipping increases signal intermodulation distortion to intolerable levels.
Another "solution" is the arrangement of a succession of cascaded filter and clipping circuits to approximate the required signal control. In practice, however, a filtering circuit as the final stage will still exhibit overshoots and, similarly, a last-stage clipper will generate harmonics which exceed the signal bandwidth constraint.
Nonetheless, a refinement of this "solution" is the subject of U.S. Pat. No. 4,383,229 to Jones noted above. This patent specifically references the FM broadcasting dilemma, and the design concept illustrated by the patent suggests that certain resonant elements of the subject lowpass filter can eliminate the harmonics generated by clipping circuits embedded within the filter circuitry. Reduction to practice of this design reveals the primary shortcomings, which are that clipping-generated harmonics are reduced in only a relatively narrow range of frequencies, and that the harmonic attenuation even at these critical frequencies is only marginally sufficient by accepted broadcasting standards. Both of these facts are noted in the patent.
As noted above, U.S. Pat. No. 4,134,074 specifically addresses the problem of filter overshoot with reference to FM broadcasting. In this patent, two nearly identical lowpass filters are placed in the signal path, one after the other. The amplitude overshoots of the first filter are isolated from, and recombined with the filtered signal in such a way that they "predict" similar overshoots in the second filter and provide a subtraction and cancellation thereof. This "solution" satisfies the requirement with full consideration of the bandwith and amplitude constraints, and reduced to practice, it performs very acceptably, but does require an otherwise-redundant lowpass filter circuit. In addition, this patent calls for a constant "group delay" characteristic in the second filter, thus measurably increasing the cost of the "solution".
To be convinced that the problem is not a simple one, and that the industry has been looking for a long time for a solution to the problem, all that is required is that one analyze U.S. Pat. No. 4,460,871. The "solution" taught by this patent is to provide a program audio signal which is both amplitude-and-bandwith-limited by a complex scheme which utilizes a system of frequency division, linear gain control within mulitple frequency bands, signal clipping and lowpass filtering. The resultant signal nonetheless contains amplitude overshoots which are then isolated by a "center-clipper", lowpass-filtered to remove clipping-induced harmonics, and finally subtracted from the primary program signal to effectively cancel the overshoots without adding out-of-band frequency components. Nonetheless, a final phase-corrected lowpass filter and "safety" clipper circuit follow the overshoot-compensation circuitry. While this design has been proved in practice, it is relatively complicated. For instance, it calls for the use of three separate lowpass filter elements, two signal relay networks, and special frequency equalization within certain branches of the signal path.
It should therefore be apparent that there is a real need in this industry for a relatively simple and low cost circuitry to provide filter overshoot protection. It is believed that the circuit forming the subject matter of this invention fills that need.
Thus, in terms of greater detail, my invention comprises comparatively simple signal-conditioning circuitry which not only places limits on the peak amplitude excursions of an input signal, but further conditions the limited input signal so as to inhibit overshoots in a subsequent lowpass filter assembly. Additionally, the lowpass filter attendant to the invention need not be tailored for use with this invention. Any popular passive or active lowpass filter configuration common to FM broadcasting service is equally suited for use in connection with this invention.
As illustrated in FIGS. 1 and 2, a simple diode input clipping circuit 2 is biased to a DC level (+/-Vref) representing the desired output amplitude limit. Signals not otherwise restricted in level by usual compression or amplitude limiting means common to broadcasting practice are input through lead 3 and will be clipped at the +/-Vref. voltage by the input clipper 2.
Due either to this clipping action or to the effects of previous program signal processing, or simply to the harmonic phase relationships within the complex program input signal, the input clipper 2 ouput signal 4 will necessarily contain frequency components which would otherwise cause a subsequent lowpass filter to overshoot the amplitude constraints of +/-Vref. As illustrated in FIG. 4(B), the signal 4 is simplified for this discussion to a worst-case, "squared-off" wave form with a lower fundamental frequency 6 and higher-order harmonics taking the form of steep, fast-rise leading and trailing wave form edges 7 and 8, respectively.
A first-order phase-lag network 9 shifts the fundamental/harmonic relationship of the squared wave form 4 to offset the harmonics in time as indicated at 12. This single-section phase-lag network 9 can shift the phase of the higher signal frequency components a maximum of 180 degrees, a figure of fundamental/harmonic phase displacement generally acknowledged as indiscernible in subjective listening tests, but in any case secondary to the greater displacement attributable to the inevitable lowpass filter.
The phase-lag network 9 thus provides a controlled and predictable signal waveform risetime 13 and falltime 14 as indicated in FIG. 4(C), but at the expense of re-violating the +/-Vref. amplitude constraint. Stated in other words, the signal harmonics 16 and 17 (FIG. 4C) have been shifted in time and out of the "risetime domain" so that they instead add back to the amplitude of the fundamental frequency.
A second clipper circuit 18 restores the +/-Vref. amplitude limit 18, but in so doing, it removes the original signal harmonics. A differential comparator circuit 21 monitors both the input to lead 12 and therefore the second clipper 18, and the output 19 from the second clipper 18 to recover the clipped-off harmonics at the output 22 of the comparator. These clipped-off harmonics are then recombined with the amplitude-limited signal 19 in a summing amplifier 23. Because the comparator 21 inverts the phase of the clipped harmonics at 22, they subtract from, rather than add to the amplitude of the limited fundamental signal 19. Thus the final output signal at 24 does not exceed the +/-Vref. limits within the passband of the subsequent lowpass filter 26, and the signal-conditioned output signal 24 from the overshoot control circuitry can be said to "undershoot" by an amount equal to the overshoot of the lowpass filter.
The re-clipped signal 19 is illustrated in FIG. 4(D), while the clipped-off harmonics 22 constituting the output of comparator 21 are illustrated in FIG. 4(E). The effect of recombining the clipped-off harmonics with the amplitude-limited signal 19 is illustrated in FIG.(4F). It may thus be said that the input to the lowpass filter has been "pre-conditioned" by anticipating the amount of the overshoot of the lowpass filter, and conditioning the input by subtracting that amount (undershoot) from the input signal 24.
While the circuitry described above compensates for, and thus eliminates overshoot in a subsequent lowpass filter, this serves only to satisfy the program signal amplitude contraints. It is assumed for purposes of this discussion that the program bandwith constraint is satisfied by adequate design of the lowpass filter circuit itself.
In practice, certain component parts within the overshoot control circuitry may be made variable so as to compensate for the overshoot characteristics of a wide range of lowpass filter circuit designs traditionally utilized in broadcasting. Such a filter design is diagrammed in FIG. 3. The circuit illustrated in FIG. 3 constitutes, as an example, a 7-pole, elliptic-function active filter and is derived from textbook formulas and is typical of what might be encountered in broadcasting practice. No claim of novelty or patentable invention in the circuit illustrated in FIG. 3 is claimed herein. I have found that sinewave response of the overshoot control circuitry is frequency-flat and unaffected at levels below the predetermined output limit (+/-Vref.), save for a 180 degree (or less) phase lag at the highest audio frequency. Though this delay adds to similar, yet normally much greater high frequency delays in the subsequent lowpass filter assembly, even several "rotations" (multiples of 360 degrees) at a 15 kHz cutoff frequency are typical and considered of no sonic importance. The preferred form of the overshoot control circuit illustrated in FIG. 2 possesses values complementary to, and provide overshoot compensation for, the example lowpass filter diagrammed in FIG. 3. Nevertheless, while this complementary relationship exists between the circuit of FIG. 2 and the circuit of FIG. 3, the overshoot control circuitry has been proven in practice to similarly provide compensation for a variety of active and passive lowpass filter designs of various orders. Additionally, the overshoot control circuit of the invention has been proven in practice to provide overshoot compensation for lowpass filter circuits utilized in applications other than FM broadcasting which, likewise, place simultaneous constraints on the amplitude and bandwith of an information signal.
In the interest of brevity in this descscription, the values of components utilized in the circuit have been shown in FIG. 2. All resistors are 5% carbon film type unless specified as 1%. Additionally, all of the operational amplifier sections are 1/2 National Semiconductor type LF353 or equivalent, and the diodes are general purpose type 1N4151 manufactured by Motorola, or equivalent.
Referring to FIG. 3, all resistors shown as 1%, the numeric value listed is in ohms, and the resistors are metal-film type. All capacitors shown are 0.0033 uF, 2.5%, polypropylene type, and all of the operational amplifiers are 1/2 National Semiconductor type LF353, or equivalent.
Having thus described the invention, what is thought to new and novel and sought to be protected by Letters Patent of the United States is as follows. | Presented is a control circuit for controlling, i.e., preventing, filter overshoot in stereophonic broadcast equipment, particularly stereophonic FM broadcasting equipment. The circuitry includes an input clipper cooperating with a phase-lag network and a second clipper to condition the primary information signal to anticipate filter overshoot and counteract it through cooperation of comparator and summing circuits that add back into the amplitude-limited signal the clipped off components that exceed in amplitude the amplitude-limited signal, but which are added back in opposite phase. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority of German Application No. 10 2007 004 440.4, filed Jan. 25, 2007, the complete disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
a) Field of the Invention
The invention is directed to an arrangement for generating extreme ultraviolet radiation by means of an electrically operated gas discharge, containing a discharge chamber which has a discharge area for a gas discharge for forming a radiation-emitting plasma, a first disk-shaped electrode and a second disk-shaped electrode, at least one of which electrodes is rotatably mounted and has an edge area to be coated by a molten metal, an energy beam source for supplying a pre-ionization beam, and a discharge circuit connected to the electrodes for generating high-voltage pulses.
The invention is further directed to a method for generating extreme ultraviolet radiation by means of an electrically operated gas discharge for forming a radiation-emitting plasma from pre-ionized emitter material in which at least one rotatably mounted, disk-shaped electrode of a pair of electrodes provided for the gas discharge is coated in the edge area by a molten metal.
b) Description of the Related Art
Studies of a large number of electrode shapes for gas discharge sources such as, e.g., Z-pinch electrodes, hollow-cathode electrodes or plasma focus electrodes have shown that the life of electrodes constructed in these ways is insufficient for EUV projection lithography.
In contrast, rotary electrodes, as they are called, have turned out to be a very promising solution for appreciably increasing the life of gas discharge sources. One advantage is that these electrodes, which are disk-shaped in particular, can be cooled better. Another advantage consists in that inevitable electrode erosion can be prevented from shortening life by a constant renewal of the electrode surface.
A device previously known from WO 2005/025280 A2 uses rotating electrodes which are immersed in a vessel containing molten metal, e.g., tin, for regenerative application of a molten metal. The metal applied to the electrode surface is evaporated by laser radiation at the location where the two electrodes are closest together, whereupon the vapor is ignited by a gas discharge to form a plasma. The cooling of the electrodes is carried out by the metal baths.
The solution proposed in WO 2005/025280 has the following disadvantages: Because of the immersion process, the rotating speed of the electrodes is limited and is not sufficient for the required output specification of an EUV source. Owing to insufficient rotating speed, subsequent arrival of unconsumed electrode portions in the discharge area is too slow, which causes instabilities in the plasma generation. The rotating speed should be designed in such a way that the electrodes continue to rotate between two successive discharge pulses by an amount that is greater than the radius of the region of influence of the preceding discharge pulse on the electrode surface.
Because of the short dwell period of the electrodes in the molten metal, cooling the electrodes by means of the melt is insufficient for the required high output specifications. However, an additional cooling of the electrodes, for example, by a throughflow of water, would allow the temperature of the electrode surface to fall below the melting temperature of the metal applied by means of the molten baths during the prolonged pauses in the pulse operation provided for radiation generation which are common in exposure processes in semiconductor fabrication. This would result in a heavy, uncontrolled accumulation of the metal layer on the electrodes. Rapidly switching the additional cooling off and on would lead to a temperature gradient between the electrode surface and the interior of the electrode. Since this temperature gradient balances out when the additional cooling is switched off, an impermissibly high heating of the coolant can occur so that any gas bubbles that might possibly occur form a thermally insulating layer which prevents efficient cooling. Further, it is difficult to adjust the layer thickness of the applied material.
OBJECT AND SUMMARY OF THE INVENTION
Therefore, it is the primary object of the invention to facilitate adjustment of the layer thickness and, in particular, to prevent an uncontrolled accumulation of the metal layer to be applied to the rotary electrodes during pauses in the pulse operation for generating radiation when, e.g., liquid flows through these rotary electrodes for efficient cooling. In this connection, the rotating speed of the rotary electrodes can be increased in particular until there is always a freshly coated surface region of the electrodes in the discharge area at repetition frequencies of several kilohertz.
This object is met in an arrangement for generating extreme ultraviolet radiation by means of an electrically operated gas discharge of the type mentioned above in that the edge area to be coated has at least one receiving area, which extends in a closed circumference along the electrode edge on the electrode surface and which is formed so as to be wetting for the molten metal, and a coating nozzle for regenerative application of the molten metal having a shutoff valve connected to a valve regulating device is directed to this receiving area.
Particularly advisable, advantageous constructions and further developments of the arrangement according to the invention are indicated in the dependent claims.
The valve regulating device is preferably connected to a temperature measuring device for measuring the surface temperature of the electrodes.
The disk-shaped electrodes are outfitted with a permanently operating cooling device. The coolant to be used can have an operating temperature below the melting temperature of a material provided for the molten metal. For example, cooling channels through which a liquid flows and which can also have temperature regulating means can be provided in the disk-shaped electrodes for cooling purposes.
The coating nozzle can be directed to the electrode surface in an area of the electrode which is located opposite the discharge area and which is provided for applying the molten metal.
In another advantageous further development of the invention, the electrodes are constructed as circular disks, are rigidly connected to one another at a mutual distance and are supported so as to be rotatable around a common axis of rotation which coincides with their center axes of symmetry. Each of the electrodes contains, on electrode surfaces facing one another, the at least one receiving area which is formed so as to be wetting for the molten metal and to which a coating nozzle is directed.
In order to prevent electrical short-circuiting, it is advantageous when a disk-shaped insulating body which penetrates into the intermediate space between the two electrodes is provided in the electrode area to which the molten metal is to be applied. In this construction, the coating nozzles which are directed to the electrode surfaces of the two electrodes can be guided through the disk-shaped insulating body from opposite sides.
The arrangement according to the invention can be further developed in a particularly advantageous manner in that the coating nozzle comprises two microstructured plates which lie one on top of the other, and a portion of a first plate is perforated by a hole structure, the second plate being outfitted with a membrane which lies opposite to the hole structure and which is flexible toward the hole structure. A closure element for the hole structure which can be pressed against the hole structure by actuating means acting at the flexible membrane is arranged on the flexible membrane so that the flow of molten metal can be interrupted. Accordingly, a movement away from the hole structure allows the molten metal to resume flowing. The two plates enclose a channel into which the hole structure opens and which is guided out of the first plate as a nozzle outlet.
The hole structure can also serve as a filter for larger particles in order to prevent clogging of the coating nozzle in that the hole structure has hole diameters that are smaller than the diameter of the nozzle outlet. Further, the coating nozzle can be constructed so as to be heatable by means of a current-carrying resistor which is arranged on the surface of at least one of the plates.
A pre-ionization of the emitter material is advantageous for igniting the plasma, particularly the evaporation of a droplet of advantageous emitter material that is injected between the electrodes. For this purpose, on the one hand, an injection device is directed to the discharge area and supplies a series of individual volumes of an emitter material, which is used to generate radiation, at a repetition frequency corresponding to the frequency of the gas discharge and by limiting the amount of the individual volumes so that the emitter material which is injected into the discharge area at a distance from the electrodes is entirely in the gaseous phase after the discharge. On the other hand, the pre-ionization beam supplied by the energy beam source is directed synchronous to the frequency of the gas discharge to a location for plasma generation in the discharge area at a distance from the electrodes at which the individual volumes arrive and are successively ionized by the pre-ionization beam.
Alternatively, the ignition of the plasma can also be initiated in that the regeneratively applied molten metal is emitter material serving for the generation of radiation and the pre-ionization beam supplied by the energy beam source is directed to the emitter material synchronous to the frequency of the gas discharge in the discharge area.
Because of the discharge process in which a plasma radiating in the EUV range is formed, a portion of the layer applied to the electrode surface in the region of influence of the plasma is evaporated or is expelled as molten material. This amounts to several 10 −7 to several 10 −6 grams per pulse. This loss of mass is compensated by the steady supply of molten metal so that a constant protective layer remains on the electrode surface even under discharge conditions with repetition frequencies of several kilohertz.
The inventive application of molten metal is also particularly advantageous because the contact between the rotary electrodes and the discharge circuit can have a particularly low inductance owing to a horizontal arrangement of the two rotary electrodes.
Therefore, in another construction of the invention, the electrodes are in electrical contact with contact elements which are oriented coaxial to the axis of rotation and which are immersed in ring-shaped, electrically separated molten metal baths which are electrically separated from one another and which communicate with a discharge circuit of the high-voltage supply.
In another construction, the electric contacting can also be carried out by means of the coating nozzle and the liquid jet.
The above-stated object is further met according to the invention by a method for generating extreme ultraviolet radiation of the type mentioned above in that the regenerative coating of the edge area is controlled during the rotation depending on the electrode surface temperature.
According to the method, the coating is interrupted when the temperature drops below a limit temperature lying above the melting temperature of a material provided for the molten metal and is continued when the temperature rises above the limit temperature.
In a particularly advantageous manner, the electrodes are cooled during coating by a coolant which has an operating temperature below the melting temperature of the material provided for the molten metal. Further, the cooling can be regulated.
The invention will be described more fully in the following with reference to the schematic drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 shows the principle according to the invention for applying a defined thin layer of a molten metal along a track on a rotating electrode surface;
FIG. 2 shows an arrangement for applying a molten metal to oppositely located, liquid-cooled electrode surfaces of two electrodes that are rigidly connected to one another and mounted so as to be rotatable around a common axis;
FIG. 3 shows the isothermal curve inside an electrode during pulse operation;
FIG. 4 shows the isothermal curve inside an electrode during a pause in the pulse operation;
FIG. 5 shows the time temperature curve on the electrode surface depending on the operating state of the radiation source;
FIG. 6 is a sectional view showing an arrangement of a controllable coating nozzle between two electrodes;
FIG. 7 shows a perspective view of a coating nozzle;
FIG. 8 shows a first construction of a radiation source with a rotary electrode arrangement according to the invention; and
FIG. 9 shows a second construction of a radiation source with a rotary electrode arrangement according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 , which serves to illustrate the principle of the invention, a disk-shaped electrode 1 is rigidly connected to a rotatable shaft 2 in such a way that the center axis of symmetry of the electrode coincides with the axis of rotation R-R. A circumferential edge track on the electrode surface serves as a receiving area 3 for a molten metal, e.g., tin or a tin alloy, and is formed so as to be wetting for this material. Surfaces for the edge track having a wetting action can be, e.g., copper, chromium, nickel or gold. However, a structural steel, heat-treated molybdenum or other electrically conductive materials are also suitable.
The rest of the electrode surface, or at least a portion of the electrode surface adjoining the receiving area, should not be wetting for the material to be applied because application of the molten metal to these areas is not wanted. Suitable non-wetting surfaces can comprise, e.g., PTFE, stainless steel, glass, or ceramic.
A coating nozzle 4 of a liquid generator, not shown, is directed to the receiving area 3 to apply the molten metal as a liquid jet 5 to the receiving area 3 in a regenerative manner during the rotation of the electrode 1 . Due to the fact that the applied liquid metal is propelled to the edge of the electrode by the centrifugal force, it is necessary to provide a spray guard 6 to prevent detaching molten metal from spreading in an uncontrolled, unlimited manner.
An energy beam, e.g., a laser beam, which serves as a pre-ionization beam 7 is directed in a discharge area 8 to an injected droplet of advantageous emitter material in order to evaporate the latter.
The adjustment of a defined layer thickness for the metal to be applied within a range between 1 μm and 20 μm requires an electrode surface temperature above the melting temperature of the material to be applied. A temperature measuring device 9 , for example, a pyrometer, carries out the measurement of the electrode surface temperature. A valve regulating device 10 connected to the temperature measuring device 9 ensures by means of a shutoff valve 11 that the supply of material and, therefore, the regenerative coating of the receiving area 3 , is interrupted at a limit temperature that is still above the melting temperature of the material to be applied. However, when the electrode surface temperature increases again above the limit temperature, the shutoff valve 11 in the material feed is opened again proceeding from the valve regulating device 10 and the coating process is continued.
In the construction shown in FIG. 2 , a first and a second disk-shaped electrode 1 , 12 are rigidly connected at a distance from one another to the rotatably mounted shaft 2 in such a way that the center axes of symmetry of the electrodes 1 , 12 coincide with the axis of rotation (R-R) of the shaft 2 . Each of the electrodes 1 , 12 contains, on surfaces that face one another, a receiving area 3 , 13 which is formed as an edge track and which has a wetting action for the molten metal, a coating nozzle 4 , 14 being directed to these receiving areas 3 , 13 . The receiving areas 3 , 13 are arranged on the electrode surfaces in such a way that they are located opposite one another.
A disk-shaped insulating body 16 , particularly an electrically insulating ceramic plate which is immersed in the intermediate space between the two electrodes 1 , 12 in an area of the electrode provided for applying the molten metal is provided for preventing electric short-circuiting between the electrodes 1 , 12 due to the liquid jets 5 , 15 of molten metal. As is shown in FIG. 2 , the two coating nozzles 4 , 14 are guided through the electrically insulating ceramic plate from opposite sides. One coating nozzle 4 acts in the direction of the force of gravity and the other coating nozzle 14 acts counter to the direction of the force of gravity.
The disk-shaped electrodes 1 , 12 are penetrated by cooling channels 17 , 18 through which a cooling liquid flows. Because cooling of this kind is relatively sluggish and therefore cannot be regulated quickly, it may happen during relatively short pauses in pulse operation that the temperature of the electrode surface drops below the melting temperature of the material to be applied. Therefore, as is described with reference to FIG. 1 , the material feed is regulated depending on the electrode surface temperature and is interrupted by shutoff valves 11 , 19 particularly when it falls below a limit temperature.
The curve of the isotherms 20 which is shown in FIG. 3 reflects a strong temperature gradient which results between electrode surfaces and the cooling channels during an ongoing pulse operation at maximum output. At a given temperature of the electrode surface of, e.g., around 500° C. at which the material applied to the edge area is liquid and at a cooling water temperature of, e.g., around 80° C., the regenerative rotational coating takes place.
On the other hand, if the temperature gradient flattens out during a pause in the pulse operation, the temperature of the electrode surface at about 120° C. lies below the melting temperature of the coating material. The temperature of the cooling water has fallen to approximately 40° C. The rotational coating is interrupted according to the invention ( FIG. 4 ).
FIG. 5 shows the time-temperature curve on the electrode surface during period t pulse of the pulse operation for the pulsed generation of radiation and during a period t pause in which the pulse operation is adjusted and during which, accordingly, no radiation is generated. When after a sharp rise in temperature at the start of the pulse operation the temperature exceeds a limit temperature T limit above the melting temperature T melt of the material to be applied, the rotational coating is switched on for a period T coat . Depending on the length of the pulse operation, an equilibrium temperature T equilibrium can occur until the temperature drops at the end of the pulse operation and, therefore, at the end of the pulsed generation of radiation. The rotational coating continues to be carried out until the temperature falls below the limit temperature T limit . This results in the formation of a sacrificial layer which can be consumed at the start of the next pulse operation for as long as the electrode temperature remains below the limit temperature T limit for the rotational coating and the coating nozzles 4 , 14 are switched off.
A coating nozzle carrying out the coating function according to FIG. 2 must have a flat structural shape in order to be able to penetrate into the gap between the disk-shaped electrodes. Further, a coating nozzle of this kind must be heatable to ensure that the molten metal remains liquid.
A coating nozzle according to FIG. 6 which is manufactured using silicon layer technology and which contains an integrated shutoff valve comprises two silicon plates 22 , 23 , which are preferably anodically bonded, and is oriented with respect to its position to the edge area of an electrode, in this instance electrode 12 , by holding elements 24 , 25 . The silicon plates 22 , 23 are formed by established methods of silicon structuring, corresponding to the nozzle function to be carried out by them, as microstructured components. Openings in the form of a hole structure 26 with hole diameters which are preferably smaller than the diameter of a nozzle outlet 27 are incorporated in the silicon plate 22 which, in this instance, lies on top. A channel 28 that is fashioned in the silicon plate 22 leads to the nozzle outlet 27 and communicates with a recess 29 in the other silicon plate 23 into which the hole structure 26 opens. The hole structure 26 can advantageously form a filter for larger particles to prevent clogging of the nozzle structure.
A flexible membrane 30 which is arranged opposite the hole structure 26 and has a die-like closure element 31 that can be moved against the hole structure 26 by the bending of the membrane 30 is incorporated in the bottom silicon plate 23 referring to the drawing. Accordingly, by means of actuating means 32 accommodated in the holding element 25 , the closure element 31 can be pressed against the hole structure 26 so that, if necessary, the supply of liquid coating material 33 , a supply channel 34 being incorporated in the holding element 24 for this purpose, can be interrupted (shown in dashes). When the force of the actuating means 32 is withdrawn, the closure element 31 disengages from the hole structure 26 so that the flow of coating material 33 can resume.
By integrating the shutoff valve in the coating nozzle, the dead volume can be advantageously minimized in such a way that afterrunning of coating material or a delay in switching on can be prevented to a great extent, which is important particularly for fast switching cycles.
Finally, the coating nozzle 21 can be constructed so as to be heatable by a current-carrying resistor 35 ( FIG. 7 ) arranged on the surface so that the molten metal does not solidify inside the coating nozzle 21 . The current-voltage characteristic of the layer-type resistor 35 can be used simultaneously as a temperature measurement signal for regulating the temperature of the coating nozzle 21 .
The radiation source shown in FIG. 8 comprises a rotary-electrode arrangement according to FIG. 2 in a discharge chamber 38 that can be evacuated by means of vacuum pumps 36 , 37 . Electric feeds to the electrodes 1 , 12 are preferably formed by ring-shaped, electrically separated melt baths 39 , 40 of molten metal, e.g., tin or other low-melting metal baths such as, e.g., gallium, in which the electrodes 1 , 12 are immersed by contact elements 41 , 42 . The contact elements 41 , 42 are either formed of a plurality of individual contacts (contact element 41 ) which are arranged along a circular ring on one electrode 12 and guided through openings 43 in the other electrode 1 so as to be electrically insulated, or they are formed as a closed cylindrical ring (contact element 42 ). Suitable partial covers of the metal baths 39 , 40 in the form of inwardly turned-down outer walls 44 , 45 prevent the pressed out molten metal from exiting from the vessels for the melt baths 39 , 40 .
Since an arrangement of the type mentioned above requires horizontally placed disk-shaped electrodes 1 , 12 or a vertically directed axis of rotation R-R, a technique for applying a molten metal such as that provided by the invention is particularly advantageous because, contrary to what was previously known, the molten metal can be applied to the electrodes 1 , 12 against the force of gravity.
By means of the rotary-electrode arrangement according to the invention, current pulses can be supplied to the electrodes 1 , 12 without wear and, above all, with low inductance. Further, to this end, there is an electrical connection leading out of the discharge chamber 38 from the melt baths 39 , 40 to capacitor elements 48 , 49 via vacuum feedthroughs 46 to 47 . The capacitor elements 48 , 49 are part of a discharge circuit which, by generating high-voltage pulses at a repetition rate between 1 Hz and 20 kHz and with a sufficient pulse size, ensures that a discharge is ignited in the discharge area 8 which is filled with a discharge gas and that a high current density is generated which heats pre-ionized emitter material so that radiation of a desired wavelength (EUV radiation) is emitted by an occurring plasma 50 .
After passing through a debris protection device 51 , the emitted radiation arrives at collector optics 52 which direct the radiation to a beam outlet opening 53 in the discharge chamber 38 . An intermediate focus ZF which is located in or in the vicinity of the beam outlet opening 53 is generated by the formation of the plasma 50 by means of the collector optics 52 and serves as an interface to exposure optics in a semiconductor exposure installation for which the radiation source, preferably formed for the EUV radiation range, can be provided.
In a particularly advantageous manner, the ignition of the plasma 50 can be initiated by evaporation of a droplet of advantageous emitter material injected between the electrodes 1 , 12 . An advantageous emitter material of this kind can be xenon, tin, a tin alloy, a tin solution, or lithium. As was already shown in FIG. 1 , the pre-ionization beam 7 which is directed to an injected droplet in the discharge area 8 synchronous to the frequency of the gas discharge serves to pre-ionize the emitter material. Therefore, in another construction according to FIG. 9 , the emitter material is introduced into the discharge area 8 in the form of individual volumes 54 , particularly at a location in the discharge area 8 provided at a distance from the electrodes 1 , 12 at which the plasma generation is carried out. The individual volumes 54 are preferably supplied as a continuous stream of droplets in dense, i.e., solid or liquid, form through an injection device 55 directed to the discharge area 8 at a repetition frequency corresponding to the frequency of the gas discharge. The pulsed pre-ionization beam 7 , preferably a laser beam of a laser radiation source, which is provided by an energy radiation source 56 , is directed to the location of the plasma generation in the discharge area 8 synchronous to the frequency of the gas discharge in order to evaporate the droplet-shaped individual volumes 54 .
When the molten metal applied to the electrodes 1 , 12 for purposes of regeneration comprises emitter material, the energy beam 7 for the pre-ionization of the emitter material can also be directed thereto synchronous with the frequency of the gas discharge, specifically either to only one electrode 1 or 12 or to both electrodes 1 , 12 simultaneously, or alternately to one and then the other electrode 1 or 12 .
While the foregoing description and drawings represent the present invention, it will be obvious to those skilled in the art that various changes may be made therein without departing from the true spirit and scope of the present invention. | The object of an arrangement and a method for generating extreme ultraviolet radiation by an electrically operated gas discharge is to improve the adjustment of the layer thickness and, in particular, to prevent an uncontrolled accumulation of the metal layer to be applied to the rotary electrodes during pauses in the pulse operation for generating radiation when, e.g., liquid flows through these rotary electrodes for efficient cooling. In this connection, the rotating speed of the rotary electrodes can be increased in particular until there is always a freshly coated surface region of the electrodes in the discharge area at repetition frequencies of several kilohertz. An edge area to be coated on at least one electrode has at least one receiving area which extends in a closed circumference along the electrode edge on the electrode surface and which is formed so as to be wetting for the molten metal. A coating nozzle for regenerative application of the molten metal is directed to this receiving area and has a shutoff valve connected to a valve regulating device. | 7 |
BACKGROUND OF INVENTION
This invention relates generally to a radiation exposure limiting scheme and more particularly to a radiation exposure limiting scheme for reducing the radiation exposure of a physician during the operation of an imaging system.
In at least one known computed tomography (CT) imaging system configuration, an x-ray source projects a fan-shaped, or a cone-shaped, beam which is collimated to lie within an X-Y-Z volume of a Cartesian coordinate system, wherein the X-Y-Z volume is generally referred to as an “imaging volume” and usually includes a set of X-Y planes generally referred to as the “imaging planes”. An array of radiation detectors, wherein each radiation detector includes a detector element, are disposed within the CT system so as to received this beam. An object, such as a patient, is disposed within the imaging plane so as to be subjected to the x-ray beam wherein the x-ray beam passes through the object. As the x-ray beam passes through the object being imaged, the x-ray beam becomes attenuated before impinging upon the array of radiation detectors. The intensity of the attenuated beam radiation received at the detector array is responsive to the attenuation of the x-ray beam by the object, wherein each detector element produces a separate electrical signal responsive to the beam attenuation at the detector element location. These electrical signals are referred to as x-ray attenuation measurements.
In addition, the x-ray source and the detector array may be rotated, with a gantry within the imaging volume, around the object to be imaged so that the angle at which the x-ray beam intersects the object constantly changes. A group of x-ray attenuation measurements, i.e., projection data, from the detector array at one gantry angle is referred to as a “view”. A “scan” of the object comprises a set of views made at different gantry angles during one revolution of the x-ray source and the detector array. In an axial scan, the projection data is processed so as to construct an image that corresponds to two-dimensional slices taken through the object.
One method for reconstructing an image from a set of projection data is referred to as the “filtered back-projection technique”. This process converts the attenuation measurements from a scan into discrete integers, ranging from −1024 to +3072, called “CT numbers” or “Hounsfield Units” (HU). These HU's are used to control the brightness of a corresponding pixel on a cathode ray tube or a computer screen display in a manner responsive to the attenuation measurements. For example, an attenuation measurement for air may convert into an integer value of −1000HU's (corresponding to a dark pixel) and an attenuation measurement for very dense bone matter may convert into an integer value of +3000 (corresponding to a bright pixel), whereas an attenuation measurement for water may convert into an integer value of 0HU's (corresponding to a gray pixel). This integer conversion, or “scoring” allows a physician or a technician to determine the density of matter based on the intensity of the computer display.
Once a suspicious mass, such as a tumor, cyst and/or lesion, is discovered an interventional procedure, such as a needle biopsy or a needle aspiration, is usually performed to obtain tissue samples needed to determine whether the mass is cancerous or benign. To do this, a needle controlled by a physician is guided to the mass using simultaneous images, such as fluoro images, produced by the imaging system. This allows a physician to manipulate the needle tip towards the suspected tumor tissue so as to obtain a tissue sample that may be used for analysis.
However, although an interventional procedure using an imaging system is an excellent diagnostic and evaluation tool, each time an interventional procedure is performed by a physician, the physician's hand is exposed to radiation emitted from the imaging system. As such, if a physician performs a large number of interventional procedures over time, the cumulative radiation dose exposure to the physician's hand over time may become quite large. Given that health problems are known to be related to increasing exposure to radiation there is concern within the medical community that physicians performing these procedures may be over exposed to imaging system radiation.
One method to address the problem of physician radiation dose exposure includes minimizing the emitter current of the imaging system and using special forceps to keep the physician's hands out of the radiation beam. Unfortunately, forceps have not been well received by the medical community because they restrict the tactile sensitivity and thus limits the delicate physician control required for interventional procedures. Moreover, it has been found that minimizing the emitter current of the imaging system during an interventional procedure while still providing sufficient radiation for qualitative image generation still results in a significant cumulative radiation dose to the physician repeatedly performing the interventional procedures. As such, these methods are not well suited for repeated interventional procedures.
The above discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.
SUMMARY OF INVENTION
The above discussed and other drawbacks and deficiencies are overcome or alleviated by a method for reducing radiation exposure from an imaging system comprising: determining an entry location; operating the imaging system so as to cause the imaging system to emit radiation having a radiation intensity; controlling the radiation intensity in a manner responsive to the entry location so as to create image data; and processing the image data so as to create processed image data.
In an alternative embodiment, a medium encoded with a machine-readable computer program code for reducing radiation exposure from an imaging system, the medium including instructions for causing a controller to implement the aforementioned method.
In another alternative embodiment, a method for reducing radiation exposure from an imaging system comprising: obtaining an object to be scanned; operating the imaging system so as to create image data; displaying the image data on an output device; and processing the image data using a processing device, wherein the processing device, determines an entry location; operates the imaging system so as to cause the imaging system to emit radiation having a radiation intensity; controls the radiation intensity in a manner responsive to the entry location so as to create image data; and processes the image data so as to create processed image data.
In another alternative embodiment, a system for reducing radiation exposure from an imaging system comprising: a gantry having an x-ray source and a radiation detector array, wherein the gantry defines a patient cavity and wherein the x-ray source and the radiation detector array are rotatingly associated with the gantry so as to be separated by the patient cavity; a patient support structure movingly associated with the gantry so as to allow communication with the patient cavity; and a processing device, wherein the processing device, determines an entry location; operates the imaging system so as to cause the imaging system to emit radiation having a radiation intensity; controls the radiation intensity in a manner responsive to the entry location so as to create image data; and processes the image data so as to create processed image data.
In another alternative embodiment, a system for reducing radiation exposure from an imaging system comprising: an imaging system; a patient support structure movingly associated with the imaging system so as to allow communication between the imaging system and a patient, wherein the imaging system generates image data responsive to the patient; and a processing device, wherein the processing device, determines an entry location; operates the imaging system so as to cause the imaging system to emit radiation having a radiation intensity; controls the radiation intensity in a manner responsive to the entry location so as to create image data; and processes the image data so as to create processed image data.
The above discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.
BRIEF DESCRIPTION OF DRAWINGS
Referring to the exemplary drawings wherein like elements are numbered alike in the several Figures:
FIG. 1 is a perspective view of a CT imaging system and a patient disposed for imaging;
FIG. 2 is a block schematic diagram of a CT imaging system;
FIG. 3 is a block diagram describing a method for reducing radiation exposure from an imaging system;
FIG. 4A is a distribution diagram showing the angular radiation distribution of an imaging system;
FIG. 4B is a distribution diagram showing the angular radiation distribution of an imaging system in accordance with an exemplary embodiment;
FIG. 5 is a graph of the radiation dose as a function of imaging system gantry angle in accordance with an exemplary embodiment; and
DETAILED DESCRIPTION
Referring to FIG. 1 and FIG. 2 a representative CT imaging system 1 is shown and preferably includes a gantry 2 having an x-ray source 4 , a radiation detector array 6 , a patient support structure 8 and a patient cavity 10 , wherein x-ray source 4 and radiation detector array 6 are opposingly disposed so as to be separated by patient cavity 10 . A patient 12 is preferably disposed upon patient support structure 8 which is then disposed within patient cavity 10 . X-ray source 4 projects an x-ray beam 14 toward radiation detector array 6 so as to pass through patient 12 . X-ray beam 14 is preferably collimated by a collimate (not shown) so as to lie within an X-Y-Z volume a Cartesian coordinate system referred to as an “imaging volume”. After passing through and becoming attenuated by patient 12 , attenuated x-ray beam 16 is preferably received by radiation detector array 6 . Radiation detector array 6 preferably includes a plurality of detector elements 18 wherein each of the detector elements 18 receives attenuated x-ray beam 16 and produces an electrical signal responsive to the intensity of attenuated x-ray beam 16 .
Although the embodiments described herein are described as applying to a computed tomography imaging system 1 , it should be stated that the embodiments described herein may be applied to any imaging system suitable to the desired end purpose, such as an imaging system having a stationary ring and/or arc of detector arrays which surround the patient cavity, wherein the radiation source moves around patient 12 irradiating the detector elements within the stationary ring and/or arc.
In addition, x-ray source 4 and radiation detector array 6 are preferably rotatingly disposed relative to gantry 2 and patient support structure 8 , so as to allow x-ray source 4 and radiation detector array 6 to rotate around patient support structure 8 when patient support structure 8 is disposed within patient cavity 10 . X-ray projection data is obtained by rotating x-ray source 4 and radiation detector array 6 around patient 12 during a scan. X-ray source 4 and radiation detector array 6 are preferably communicated with a control mechanism 20 associated with CT imaging system 1 . Control mechanism 20 preferably controls the rotation and operation of x-ray source 4 and/or radiation detector array 6 .
Control mechanism 20 preferably includes an x-ray controller 22 communicated with x-ray source 4 , a gantry motor controller 24 , and a data acquisition system (DAS) 26 communicated with radiation detector array 6 , wherein x-ray controller 22 provides power and timing signals to x-ray source 4 , gantry motor controller 24 controls the rotational speed and angular position of x-ray source 4 and radiation detector array 6 and DAS 26 receives the electrical signal data produced by detector elements 18 and converts this data into digital signals for subsequent processing. CT imaging system 1 also preferably includes an image reconstruction device 28 , a data storage device 30 and a processing device 32 , wherein processing device 32 is communicated with image reconstruction device 28 , gantry motor controller 24 , x-ray controller 22 , data storage device 30 , an input device 34 and an output device 36 . Moreover, CT imaging system 1 also preferably includes a table controller 38 communicated with processing device 32 and patient support structure 8 , so as to control the position of patient support structure 8 relative to patient cavity 10 .
In accordance with an exemplary embodiment, patient 12 is preferably disposed on patient support structure 8 , which is then positioned by an operator via processing device 32 so as to be disposed within patient cavity 10 . Gantry motor controller 24 is operated via processing device 32 so as to cause x-ray source 4 and radiation detector array 6 to rotate relative to patient 12 . X-ray controller 22 is operated via processing device 32 so as to cause x-ray source 4 to emit and project a collimated x-ray beam 14 toward radiation detector array 6 and hence toward patient 12 . X-ray beam 14 passes through patient 12 so as to create an attenuated x-ray beam 16 , which is received by radiation detector array 6 .
Detector elements 18 receive attenuated x-ray beam 16 , produces electrical signal data responsive to the intensity of attenuated x-ray beam 16 and communicates this electrical signal data to DAS 26 . DAS 26 then converts this electrical signal data to digital signals and communicates both the digital signals and the electrical signal data to image reconstruction device 28 , which performs high-speed image reconstruction. This information is then communicated to processing device 32 , which stores the image in data storage device 30 and displays the digital signal as an image via output device 36 .
Referring to FIG. 3 , a flow diagram describing a method for reducing radiation exposure 100 from an imaging system 1 is shown and discussed. In accordance with an exemplary embodiment, an entry location 40 is determined, as shown in step 102 . During an interventional procedure an instrument, such as a needle, is guided by a physician's hand with the help of imaging system 1 and entry location 40 represents the location of the physician's hand which is disposed within patient cavity 10 and hence within a radiation field 42 , wherein radiation field 42 includes an average radiation distribution 44 and an angular radiation distribution 46 . In addition, entry location 40 may be disposed within a predetermined entry angular range 50 . Although, entry location 40 is preferably determined via an entry cursor and/or a target location cursor, wherein the entry cursor and/or target location cursor is communicated with processing device 32 via input device 34 , entry location 40 may be determined and/or estimated using any information, method and/or device suitable to the desired end purpose, such as processing of data extracted from a Fluoro scan procedure. For example, an on-line assessment of the angular position of entry location 40 (& hence physician's hand) may be performed in a manner responsive to changes of the x-ray attenuation distribution during the intervention process and/or a manner responsive to the x-ray distribution determined during the primary non-fluoro scan and/or in a manner responsive to any other suitable means of detection, such as Ultrasound and/or optical.
Referring to FIG. 4 a, imaging system 1 is operated so as to cause x-ray source to emit radiation in the form of x-ray beam 14 . As x-ray source 4 and radiation detector array 6 rotate around patient cavity 10 x-ray beam 14 creates radiation field 42 within patient cavity 10 wherein radiation field 42 includes average radiation distribution 44 and angular radiation distribution 46 , as shown in step 104 . As x-ray source 4 rotates around patient cavity 10 the gantry angular position or the angle at which x-ray beam 14 intersects patient 12 , varies between 0° and 360°.
Radiation intensity level 48 is then controlled in a manner responsive to entry location 40 and/or entry angular range 50 so as to create image data, as shown in step 106 . Referring to FIG. 4 B and FIG. 5 , for a 360° image reconstruction 52 as the gantry angular position approaches entry location 40 and/or entry angular range 50 , radiation intensity level 48 is decreased by a predetermined minimization amount so as to minimize the radiation intensity level 48 in the area of entry location 40 . Similarly, as the gantry angular position approaches 180° from entry location 40 and/or entry angular range 50 , radiation intensity level 48 is increased by a predetermined minimization amount so as to maximize the radiation intensity level 48 in the area of 180° from entry location 40 . Predetermined minimization amount may be equal to the radiation intensity level so as to reduce the radiation intensity level at entry location 40 and/or within entry angular range 50 to be zero. Moreover, predetermined minimization amount may be any value suitable to the desired end purpose.
For a 180° image reconstruction 60 , as the gantry angular position approaches entry location 40 and/or entry angular range 50 , radiation intensity level 48 is decreased by a predetermined minimization amount so as to minimize the radiation intensity level 48 in the area of entry location 40 . Similarly, as the gantry angular position approaches ±90° from entry location 40 and/or entry angular range 50 , radiation intensity level 48 is increased by a predetermined minimization amount so as to maximize the radiation intensity level 48 in the area of ±90° from entry location 40 and/or entry angular range 50 . This advantageously allows for a nearly constant average radiation distribution 44 through out the scan while allowing for the angular radiation distribution 46 to be modified. This advantageously allows the noise level of the image to be compensated by amplification of the emitter tube current at the opposing angle (180° for 360° recon) or the perpendicular angles (±90° for 180° recon). Moreover, the radiation exposure to the physician's hand will be dramatically reduced by the absorption of the patient's body (and, in most cases, by the patient table).
In addition, radiation intensity level 48 may be controlled by using a pre-determined radiation absorption angular profile (as measured during a previous rotation of the fluoroCT process and/or from a previously acquired static scan) as an input for additional modulation of x-ray beam 14 in order to significantly reduce patient radiation exposure dose. This pre-determined measure of radiation may be dependent upon the anatomy of patient 12 within the scan field. For example, if patient absorption at specific radiation source angles is low, as may be the case when x-ray source 4 is positioned anterior or posterior to the chest area of patient 12 , then the radiation beam intensity may be significantly reduced at these angles without affecting image quality. Alternatively, when patient absorption is high, as may be the case for lateral radiation source angles, such as through the shoulder area or hip area of patient 12 , x-ray source 4 may deliver a full un-modulated radiation exposure dose.
Another related feature includes using the angular current profile as an input for a weighting function in the reconstruction of the image. As the x-ray radiation is reduced the limited photon statistics give rise to increased image noise. Special noise reduction techniques and algorithms may be applied in the reconstruction process to reduce any image performance degradation. These algorithms may be controlled either by obtaining a measure of actual photon statistics during the acquisition process and/or by the priory knowledge of the angular current profile.
Furthermore, in order to eliminate streaks and other noise pattern artifacts, in the fluoro images, more than 180+fan degrees of data may be used for image reconstruction (e.g. 270 deg). The additional data beyond the last 180 degrees of scanning may be used to reduce image noise and streaks and significantly improve the image quality. The reduction in temporal resolution that this “over-scan” reconstruction entails may not be significant while using very fast rotation speed (≦0.5 sec) and a weighting function that includes only a small amount of “old” data.
Furthermore, in order to eliminate streaks and other noise pattern artifacts, in the final (static) image, more than 360 degrees of data may be used for image reconstruction (e.g. 540 deg). This implementation may occur following the ‘dynamic’ image reconstruction and display phase of FluoroCT imaging and may be used as a means of improving the quality of the final static image that remains on output device 36 after the real-time imaging has stopped. The additional data beyond the last 360 degrees of scanning may be used to reduce image noise and streaks and significantly improve the static image quality of this final image. The reduction in temporal resolution that this over-scan reconstruction entails may not be significant when viewing the static image at the completion of the FluoroCT procedure.
Referring to FIG. 6 , the radiation intensity level 48 may also be controlled in a manner responsive to entry location 40 and/or entry angular range 50 so as to prevent radiation from being emitted from imaging system 1 while the gantry angular position approaches the entry location 40 and/or is within entry angular range 50 . Radiation may be prevented from being emitted from imaging system 1 via any means suitable to the desired end purpose, such as by an electrical means (switch), a mechanical means (shutter) and/or an electro-mechanical means. This reduces and/or eliminates radiation exposure to a physician's hand while allowing the interventional procedure to continue. Moreover, direct radiation to the physician's hand will be eliminated while indirect radiation will be dramatically reduced by the absorption of the patient's body.
This image data is then processed so as to create processed image data, as shown in step 108 . This advantageously allows for a significant dose reduction to the physician during interventional procedures using a FluoroCT scan while preserving patient dose and image quality.
This invention advantageously allows for interventional procedures to be performed while minimizing and/or eliminating radiation exposure to the performing physician. In addition, potential health problems may advantageously be avoided by reducing the physicians' exposure to x-ray radiation to more acceptable levels.
In accordance with an exemplary embodiment, a method for reducing radiation exposure from an imaging system 100 may be applied by any imaging system suitable to the desired end purpose, such as a magnetic resonance imaging (MRI), ultrasound, X-Ray, CT and/or PET.
In accordance with an exemplary embodiment, processing of FIG. 3 may be implemented through processing device 32 operating in response to a computer program. In order to perform the prescribed functions and desired processing, as well as the computations therefore (e.g., the execution of Fourier analysis algorithm(s), the control processes prescribed herein, and the like), the controller may include, but not be limited to, a processor(s), computer(s), memory, storage, register(s), timing, interrupt(s), communication interfaces, and input/output signal interfaces, as well as combinations comprising at least one of the foregoing. For example, the controller may include input signal filtering to enable accurate sampling and conversion or acquisitions of such signals from communications interfaces. It is also considered within the scope of the invention that the processing of FIG. 3 may be implemented by a controller located remotely from processing device 32 .
As described above, the present invention can be embodied in the form of computer-implemented processes and apparatuses for practicing those processes. The present invention can also be embodied in the form of computer program code containing instructions embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, or any other computer-readable storage medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the invention. Existing systems having reprogrammable storage (e.g., flash memory) can be updated to implement the invention. The present invention can also be embodied in the form of computer program code, for example, whether stored in a storage medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, such as electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the invention. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.
While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. | A method and system for reducing radiation exposure from an imaging system including determining an entry location, operating the imaging system so as to cause the imaging system to emit radiation having a radiation intensity, controlling the radiation intensity in a manner responsive to the entry location so as to create image data and processing the image data so as to create processed image data. In an alternative embodiment, a medium encoded with a machine-readable computer program code for reducing radiation exposure from an imaging system, the medium including instructions for causing a controller to implement the aforementioned method. | 0 |
RELATED APPLICATION DATA
This application claims benefit of U.S. provisional application Ser. No. 60/261,753 filed on Jan. 17, 2001, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates to usage rights for controlling the distribution and use of digital content, and more particularly to a method and an apparatus for managing usage rights to be associated with content.
The Internet is a worldwide network of computers linked together by various hardware communication links all running a standard suite of protocols known as TCP/IP (transmission control protocol/Internet protocol). The growth of the Internet over the last several years has been explosive, fueled in the most part by the widespread use of software tools (known as “browsers”) which allow both HTML (hypertext markup language) viewing and HTTP (hypertext transfer protocol) navigation. Browsers allow a simple GUI (graphical user interface) to be used to communicate over the Internet. Browsers generally reside on the computer used to access content on the Internet, i.e. the client computer. HTTP is a component on top of TCP/IP and provides users access to documents of various formats using the standard page description language known as HTML and more recently XML (extensible markup language) and XHTML (extensible hypertext markup language), a reformulation of HTML into XML. The collection of servers on the Internet using HTML/HTTP has become known as the “World Wide Web” or simply the “Web.”
Through HTML, XHTML, and interactive programming protocols, the author of content is able to make the content available to others by placing the content, in the form of a Web page, on an Internet Web server. The network path to the server is identified by a URL (Uniform Resource Locator) and, generally, any client running a Web browser can access the Web server by using the URL. A client computer running a browser can request a display of a Web page stored on a Web server by issuing a URL request through the Internet to the Web in a known manner.
Since the Web utilizes standard protocols and a standard rendering engine, i.e. the rendering engine of the browser, the Web has become ubiquitous. One of the primary applications of the Web has been distribution of content in the form of documents. A “document”, as the term is used herein, is any unit of information subject to distribution or transfer, including but not limited to correspondence, books, magazines, journals, newspapers, other papers, software, photographs and other images, audio and video clips, and other multimedia presentations. A document may be embodied in printed form on paper, as digital data on a storage medium, or in any other known manner on a variety of media.
However, one of the most important issues impeding the widespread distribution of digital documents, i.e. documents in forms readable by computers, via electronic means, and the Internet in particular, is the current lack of protection of the intellectual property rights of content owners during the distribution and use of those digital documents. Efforts to resolve this problem have been termed “Intellectual Property Rights Management” (“IPRM”), “Digital Property Rights Management” (“DPRM”), “Intellectual Property Management” (“IPM”), “Rights Management” (“RM”), and “Electronic Copyright Management” (“ECM”), collectively referred to as “Digital rights management (DRM)” herein.
In the world of printed documents, a work created by an author is usually provided to a publisher, which formats and prints numerous copies of the work. The copies are then sent by a distributor to bookstores or other retail outlets, from which the copies are purchased by end users. While the low quality of copying and the high cost of distributing printed material have served as deterrents to unauthorized copying of most printed documents, it is far too easy to copy, modify, and redistribute unprotected digital documents. Accordingly, some method of protecting digital documents is necessary to make it more difficult to copy and distribute them without authorization.
Unfortunately, it has been widely recognized that it is difficult to prevent, or even deter people from making unauthorized distributions of electronic documents within current general-purpose computing and communications systems such as personal computers, workstations, and other devices connected over communications networks, such as local area networks (LANs), intranets, and the Internet. Many attempts to provide hardware-based solutions to prevent unauthorized copying have proven to be unsuccessful. The proliferation of “broadband” communications technologies will render it even more convenient to distribute large documents electronically, including video files such as full length motion pictures, and thus will remove any remaining deterrents to unauthorized distribution of documents. Accordingly, DRM technologies are becoming very useful.
Two basic schemes have been employed to attempt to solve the document protection problem: secure containers and trusted systems. A “secure container” (or simply an encrypted document) offers a way to keep document contents encrypted until a set of authorization conditions are met and some copyright terms are honored (e.g., payment for use). After the various conditions and terms are verified with the document provider, the document is released to the user in clear form. Commercial products such as Cryptolopes by IBM™ and by InterTrust's ™ Digiboxes fall into this category. Clearly, the secure container approach provides a solution to protecting the document during delivery over insecure channels, but does not provide any mechanism to prevent legitimate users from obtaining the clear document and then using and redistributing it in violation of content owners's intellectual property.
Cryptographic mechanisms are typically used to encrypt (or “encipher”) documents that are then distributed and stored publicly, and ultimately privately deciphered, i.e. unencrypted, by authorized users. This provides a basic form of protection during document delivery from a document distributor to an authorized user over a public network, as well as during document storage on an insecure medium.
In the “trusted system” approach, the entire system is responsible for preventing unauthorized use and distribution of the document. Building a trusted system usually entails introducing new hardware such as a secure processor, secure storage and secure rendering devices. This also requires that all software applications that run on trusted systems be certified to be trusted. While building tamper-proof trusted systems is still a real challenge to existing technologies, current market trends suggest that open and untrusted systems such as PC's and workstations using browsers to access the Web, will be the dominant systems used to access copyrighted documents. In this sense, existing computing environments such as PC's and workstations equipped with popular operating systems (e.g., Windows™, Linux™, and UNIX) and rendering applications such as browsers are not trusted systems and cannot be made trusted without significantly altering their architectures. Of course, alteration of the architecture defeats a primary purpose of the Web, i.e. flexibility and compatibility.
U.S. Pat. No. 5,715,403, the disclosure of which is incorporated herein by reference, discloses a system for controlling the distribution of digital documents. Each rendering device has a repository associated therewith. Usage rights labels are associated with digital content. The labels include usage rights that specify a manner of use of the content and any conditions precedent for exercising the manner of use. U.S. Pat. No. 5,052,040 discloses the use of a label prefixed to digital files so that different users can have specific encryption capability and rights with respect to the same file.
The proliferation of the Web, and its usefulness in document distribution, makes it desirable to apply DRM features to many documents in various systems. However, there are no universally accepted formats or mechanisms for creating usage rights, associating usage rights with content, or generally managing usage rights. Accordingly, applications form various vendors are not compatible with usage rights associated with various documents in a consistent manner.
SUMMARY OF THE INVENTION
The embodiment described below provides an easy to use application or GUI so any authorized user can create and mange usage rights. This is accomplished by providing an object oriented model that comprehends rights specification at different levels of the document life cycle (creation, distribution, retail, etc), and provides powerful capabilities (such as batch support and rights delegation).
A first aspect of the invention is a system for manipulating and managing usage rights adapted to be associated with digital content. The system comprises a rights module operative to specify a manner of use, a conditions module operative to specify one or more conditions necessary for exercising a manner of use, and an offers module operative to combine one or more rights specified by said rights module and one or more conditions specified by the conditions module to create a rights offer object of usage rights and associated conditions necessary for exercising a manner of use indicated by the usage rights.
A second aspect of the invention is a label for expressing usage rights adapted to be associated with digital content. The label comprises usage rights specifying a manner of use, conditions specifying one or more conditions necessary for exercising a manner of use, wherein one or more of said usage rights and one or more of said conditions are combined to create a rights offer object, and a label container including at least one rights offer object.
BRIEF DESCRIPTION OF THE DRAWING
The invention is described through preferred embodiments and the attached drawing in which:
FIG. 1 is a block diagram of a content distribution system that can be used with the preferred embodiment;
FIG. 2 is schematic illustration of a rights label in accordance with the preferred embodiment;
FIG. 3 is a block diagram of the editor of the preferred embodiment;
FIG. 4 is an example of an offer creation and editing screen of the preferred embodiment;
FIG. 5 is an example of a label creation and editing screen of the preferred embodiment;
FIG. 6 is an example of a license editing screen of the preferred embodiment;
FIG. 7 is an example of a simple edit screen of the preferred embodiment;
FIG. 8 is an example of an advanced edit screen of the preferred embodiment; and
FIG. 9 is an example of a label management screen of the preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a block diagram of a system for the electronic distribution that can be used with the preferred embodiment. Author 110 creates original content and passes it to distributor 120 for distribution. Ordinarily, author 110 is the creator of the content. However, the term “author” as used herein can be the creator, owner, editor, or other entity controlling the content or an agent (e.g. a publisher) of one of those entities. Also author 110 may distribute documents directly, without involving another party such as distributor 120 , and thus the author and distributor may be the same entity. However, the division of functions set forth in FIG. 1 is efficient, as it allows author 110 to concentrate on content creation and not the administrative functions of distribution. Moreover, such a breakdown facilitates economies of scale by permitting distributor 120 to associate with a number of authors 110 . The term “document”, as used herein, generally refers to any type of document, such as text, audio, or other data, including any encryption, formatting, or the like. The term “content”, as used herein, generally refers to a document or any other object that can have usage rights associated therewith. For example the content can be a document service, such as a Web service defined by Web Service Description Language (WSDL) and published in a Uniform Description, Discovery, and Integration (UDDI) directory.
Distributor 120 associates a rights label, which is described in detail below, with the content. The rights label can be registered with clearinghouse 150 and stored in a label repository, such as a memory device associated with clearinghouse 150 . The content can be stored in a content repository, such as a storage device associated with distributor 120 . Alternatively, the label and content can be stored on the same device. Distributor 120 distributes content to user 130 , through a digital storefront on the Web or the like, upon request. In a typical electronic distribution model, the content is distributed in encrypted form. Distributor 120 encrypts the content with a random key and then encrypts the random key with a public key corresponding to user 130 . Thus the encrypted document is customized solely for the particular user 130 . User 130 is then able to use their private key to unencrypt the random key and use it to unencrypt and view the document. For example, PKI technology is used with the preferred embodiment. However, any other type of ciphering, encryption, watermarking, or other security or obfuscation methods can be used.
The private key, or other identification information is issued to user 130 upon purchase of an appropriate rights label (described in detail below) from clearinghouse 150 . In particular, payment for the document is passed from user 130 to distributor 120 by way of clearinghouse 150 which collects requests from user 130 and from other users who wish to use particular content. Clearinghouse 150 also collects payment information, such as debit transactions, credit card transactions, or other known electronic payment schemes, and forwards the collected payments as a payment batch to distributor 120 . Of course, clearinghouse 150 may retain a share of the payment as a fee for the above-noted services. Distributor 120 may retain a portion of the batch payment from clearinghouse 150 for distribution services and forward a payment (for example royalties) to author 110 .
User 130 requests a rights label corresponding to desired content from clearinghouse 150 and provides clearinghouse 150 with information, such as credit card and charge authorization information, personal information, or the like to permit clearinghouse 150 to authorize user 130 in a known manner. Once user 130 has been authorized and obtained the rights label from clearinghouse 150 , user 130 may request the associated content from distributor 120 by submitting the rights label, including authorization identification, such as a private key, obtained from clearinghouse 150 . Distributor 120 parses the rights label to determine which content is associated therewith and permits the content to be decrypted and used in accordance with the usage rights in the rights label in a known manner. If the rights label is not presented, or the conditions thereof are not satisfied, the content is not made available for use.
Each time user 130 requests a rights label corresponding to a document, an accounting message is sent to audit server 140 which ensures that each label request by user 130 matches with a subsequent document sent by distributor 120 to user 130 . Accounting information is received by audit server 140 directly from distributor 120 . Any inconsistencies are transmitted via a report to clearinghouse 150 , which can then adjust the payment batches made to distributor 120 accordingly. This accounting scheme is present to reduce the possibility of fraud in electronic document distribution and to handle any time-dependent usage permissions that may result in charges that vary, depending on the duration or other extent of use. Audit server 140 and clearinghouse 150 , in combination, can serve as transaction aggregator 160 which functions to aggregate plural transactions over a period of time, and charge distributor 120 in an appropriate manner to reduce the accounting overhead of distributor 120 . The model for electronic document distribution illustrated in FIG. 1 can be applied to distribution of documents using rights labels of the preferred embodiment disclosed herein.
The preferred embodiment incorporates a model for usage rights specifications or “rights specifications.” Software applications and user interfaces can be created to conform to the model to facilitate the workflow in creating a rights specification. As an example, the underlying mechanism can use a grammar, such as that disclosed in U.S. Pat. No. 5,715,403, U.S. provisional application Ser. No. 60/261,753, the disclosure of which are incorporated herein by reference. The invention can be applied to any language or grammar for rights specifications. The term “rights specification” as used herein refers generally to the association of usage rights with content.
The model includes four components, a rights component, a conditions component, an offer component, and a label component. Each component can be created by a corresponding software module. Of course, the modules need not be separate physical entities, or even separate lines of code, but are merely used as in the preferred embodiment a way of describing the functional aspect of the software used to create usage rights labels in accordance with the preferred embodiment. Each component is discussed in detailed below.
Usage rights or “rights”, specify manners of use. For example, a manner of use can include the ability to view, print, copy distribute or the like as set forth in U.S. Pat. No. 5,715,403 the disclosure of which is incorporated herein by reference. Rights can also be bundled as in “view and print.” More sophisticated usage rights can be, for example, the right to sell if the principal is an intermediary such as a wholesaler.
Conditions must be satisfied in order to exercise the manner of use in a specified usage right. For, example a condition may be the payment of a fee, submission of personal data, or any other requirement desired before permitting exercise of a manner of use. Conditions can also be “access conditions” for example, access conditions can apply to a particular group of users, say students in a university, or members of a book club. In other words, the condition is that the user is a particular person or member of a particular group. Rights and conditions can exist as separate entities, but by themselves are not very useful. For example, a right, such as right to view content, can be specified, but without any association to conditions it is not very useful.
Rights offers, or “offers” include a rights component and a conditions component and a relationship therebetween. Accordingly, an offer can present a choice that a consumer, i.e. user of content, can make. For example, and offer can be to view and print unlimited number of copies (usage rights) for a payment of $5.00 (condition). An offer can be created by selecting rights and the conditions that are associated with each right or bundle of rights. In more sophisticated examples, a rights offer could be, for example, an offer to allow the sale of 500 copies at a specified fee if the user is a wholesaler.
FIG. 2 schematically illustrates rights label 200 in accordance with the preferred embodiment. Rights labels, or “labels” are collections of rights offers 220 . For example, label 100 can include one or more offers 220 , and a user has the option to select any of the offers 220 to use the content in accordance with the usage rights 222 of the selected 220 offer after satisfying the conditions 224 of the selected offer 220 . Labels 200 can be constructed by selecting one or more offers and bundling them together in a package.
As noted above, rights and conditions, as distinct entities, are an abstract concept with little practical use. For example, distributors and the like do not generally need to create rights and conditions independently of offers. In the model of the preferred embodiment, the basic elements that are going to be used and reused are rights offers 220 and rights labels 200 . Rights offers 220 are very useful because they form the basis for offering something, i.e. content for use. As noted above, an offer 220 can consist of a “bundle” of rights 222 and the condition 224 or conditions for that bundle. So the bundling of rights 222 can be accomplished when an offer 220 is created. For example, as a single offer 220 , a publisher may wish to provide both view and print together as usage rights 222 . Conditions 224 can also be specified when offer 220 is created. Thus offer 220 precisely defines right 222 or a rights bundle and the associated condition 224 or conditions. Offers 220 have practical use independent of labels as will became apparent form the description below.
The preferred embodiment permits manipulation of offers 220 in an object oriented manner. For example a distributor or author may create many offers 220 and keep them organized in a folder, i.e. directory, represented as a graphical object. The offers 220 , as objects, may be named with descriptive practical names such as “Confidential Doc for Mgrs.ofr”. Note that offer objects are denoted with the file extension “.ofr” in the preferred embodiment. However, any file extensions or nomenclature can be used to name offer objects. Offer objects, the corresponding graphical icon, and offers 220 themselves represent the same entity and thus will be collectively referred to as “offers 220 .”
In order to be used to regulate the use of content, offers 220 should be associated with content. Rights labels 200 , or “labels” specify the association of offers 220 to content. Labels 200 specify the digital content, through a link or the like known as content specification 226 , and can also include metadata of the content. For example, metadata in a label can include the title of the content, the author, or any other relevant information. Further, labels 200 can specify, i. e., be associated with, portions of the content (as in a composite document) and can include metadata associated with each portion. Thus, a single label 200 can include metadata for the entirety of content and metadata for portions of the content.
Content can be associated with one or more offers of a label. Further, labels can support “precedence rules” to facilitate specification. For example, if every portion of content has the same offer, the offer can be associated with the first portion of content. As objects, labels can be deleted, renamed, or organized in a folder as will become apparent from the disclosure below.
An editor, in the form of computer software to be run on a general purpose computer (such as a personal computer running the Microsoft Windows 2000™, operating system) can be provided to create and edit offers and labels and to manage the same. The editor can also be used to create label templates, or “templates.” A label template contains one or more offers, but has no document association. Otherwise, a label template is similar to a label. Templates can be used, an reused, as is or edited prior to being associated with content to facilitate the creation of labels. For example, common combinations of offers can be used as a template to reduce the need to create a new label each time the combination of offers is needed.
FIG. 3 illustrates label editor 300 of the preferred embodiment capable of creating and manipulating offers, creating and manipulating label templates, and creating and manipulating labels. Further, editor 300 provides object oriented managing functions as described below. Editor 300 includes rights module 322 for specifying usage rights 222 , conditions module 324 for specifying conditions 224 , offer module 326 for combining usage rights 222 and conditions 324 into offers 220 , and label module 328 for combining one or more offers 220 and associating the same with content to define labels 200 . User interface module 330 provides a graphical user interface for each of the other modules as described in detail below.
User interface module 330 presents the editor, i.e., a person creating, editing, or managing offers and labels, with a screen display window where all existing labels are listed as described below. Menu items will allow the user to create a new label or to edit/copy/delete and otherwise manage a selected label or offer or a selected group of labels and or offers. Labels and offers can be represented as graphical objects, i.e. icons, and the user can either select an existing icon and select an “edit” command or select the “new” command to create a new label or offer.
Assuming a new offer is to be created and the user has selected the “new” command, the user is presented with the “new offer” screen illustrated in FIG. 4 . In this screen, the user will be able to enter the name of the offer in field 406 . For example a descriptive name such as “view and print for one dollar” can be used. As will become apparent below, the functionality of rights module 322 , conditions module 324 , and offers module 326 are presented through user interface module 330 to permit creation and editing of offers 220 .
Pull down menus 402 each include a list of various predetermined rights to permit the user to select from the lists one or two usage rights or combinations of usage rights. Of course, there can be more than two pull down menus 402 to permit a more flexible selection of usage rights. Usage rights in the list can include “PRINT,” “COPY,” “VIEW,” “DISTRIBUTE,” or any other manner of use. Also, each list can include combinations of rights, such as “PRINT and VIEW.” Similarly, pull down menus 404 each include lists of various predetermined conditions to permit the user to select from the lists conditions or combinations of conditions. It can be seen that the conditions lists are divided into a “FEE” list, a “TIME” list, and an “ACCESS” list. Of course, these lists can be combined or segregated further to include other lists. Fees can include various monetary amounts, times can include various time periods (such as one month after purchase), and access can include various persons, groups, or everyone. It can be seen that the combination of selections from pull down menus 404 can be used to flexibly define conditions, such as “upon payment of $1.00, anyone can use the content in accordance with the usage rights for an unlimited time period” as in for example FIG. 4 . An icon corresponding to an existing offer can be “opened” by double clicking with a mouse for example, to present screen 400 and permit rights and conditions to be edited by making selections from pull down menus 402 and 404 .
Once offers 220 are created, they can be managed like any other kind of objects and manipulated to create labels 200 through label module 328 and user interface 330 . FIG. 5 illustrates a display screen for selecting offers 220 , in a graphical manner, bundling the offers, and associating the bundle with content to create labels 200 . In the example of FIG. 5 , there are four offers 220 , each represented by an icon in list window 502 and having a descriptive name. Of course, there can any number of offers 220 and they can be displayed in any manner, such as in the form of a list, a directory tree, or the like. User interface module 330 is operative to permit the user browse through offers 220 and “open” offers 220 examine the conditions and rights thereof, through a display similar to that in FIG. 4 , for example. Creation of label 200 can be accomplished by “dragging” one or more desired offers 220 into offers window 504 representing a “rights label container.” Drop down menus 506 can be used to specify the filename of content to be associated with the offers, the portion of the content corresponding to the offers, and metadata relating to the content. Note that the drop down menu 506 corresponding to metadata is merely a generic representation for the sake of simplicity. However drop down menus or data entry fields for “author,” “title,” “publication date,” or any other specific metadata can be provided. Editing of Labels 200 can be accomplished in a similar manner by selecting icons representing labels 200 to open a window similar to that of FIG. 5 . Opening one of offer icons 220 will display a screen similar to that of FIG. 4 for editing offers 220 . Label 200 can be can saved as and object by entering a descriptive name in field 508 and selecting a “save” command.
User interface module 330 can present the user with sections through pull down menus or lists, browse boxes, fields, buttons, or any other interface for selecting or specifying the various values. Labels 200 can be saved, copied, moved and the like, as an object, similar to any type of file or object. The model of the preferred embodiment provides a level of abstraction that shields, the editor from computer code. However, labels 200 actually are comprised of some type of underlying computer readable file having code, data, grammar, or the like, all referred to as “code” herein. For example, the underlying code can be in the XrML™ grammar or in the grammar disclosed in U.S. Pat. No. 5,715,403. In some cases, it may be desirable to have access to this computer readable code of labels 200 to manipulate labels 200 in various ways.
FIG. 6 shows a screen presented by user interface module 330 for facilitating editing the code of label 200 . In window 602 , the hierarchical structure of thef file named “license” and corresponding to a label 200 is presented at 602 . For the license file can include a work 604 , i.e., content, that has been encrypted, and corresponding signatures or keys 606 for each work. A description of the selected work is presented in window 604 . Editor 300 can load files, such as XrML files and check their syntax and semantics. Also, editor 300 can be used to manipulate the underlying files to label 200 to permit more flexible creation of labels. For different industries (such as the music industry or book publishing industry), different templates can be created to customize to the needs of that industry. For example, units used for book publishers may be chapters, pages, or volumes, while units used for the music industry can be tracks or minutes. For each industry, one general purpose template that covers the conventional parameters can be used as the default template. By using the hierarchical, i.e., free, structure of FIG. 6 , one node can be copied to another node, making the changes in the relevant fields much easier and faster. For the management of the labels 200 (for example, finding expired labels 200 ), labels 200 can be selected in order by issue date or expiration date as described below.
Upon opening file user interface module 330 displays a code editor screen. FIG. 7 shows an example of a screen of a code editor presented by user-interface module 330 , which has two settings: “Simple Edit” and “Advanced Edit.” When “Simple Edit” is selected a simple menu interface 700 , is displayed for managing labels 200 , as shown in FIG. 7 . The simple interface includes display fields for the label name, the URL of the label, rights, fees, and metadata.
FIG. 8 is an example of a screen displayed when advanced edit is selected. It can be seen that the code, XrML code in the preferred embodiment, is displayed in an edit window for direct editing with a conventional text editor interface or the like. This permits a “hands on” approach to label editing that is very flexible and leverages the full power of the code used for creating labels 200 . Only a potion of the code is illustrated in FIG. 8 . It can be seen however, that the code includes metadata, a key, and other information in the XrML format.
FIG. 9 illustrates another screen displayed by user interface module 330 for management of labels 200 . Labels 200 are displayed as a list of label names. The list can be sorted based on the date or any other parameter in the corresponding label 200 . Label searches can be conducted by title and/or date of last modification. Some or all labels can be selected, highlighted, edited, or deleted. For multiple selections, the same settings are applied to all selected labels to accomplish batch processing on labels. For example, in batch processing, all prices of similar books can be set at $10.00, simultaneously. Editing can be accomplished through screens similar to those described above. Labels 200 can be organized in folders, as noted above. When an offer 220 or rights template is applied to a folder, all labels 200 inside the folder will be associated with that offer or template.
The interface and model of the preferred embodiment offers multiple advantages over conventional systems. For example, the process of preparing labels can be automated by assigning an offer or template to a label container, adding content and metadata to the container in the manner described above. The container can be in the form of a folder or window and the objects can be dragged into the folder or window.
Further, content preparation functions can be integrated into existing applications (for example, into a DocuShare™ application where the content is “prepared” on its way to the repository). Another example is “preparation-on-the-fly” for “just-in-time” publishing applications. Since labels, offers, and templates are in the form of objects, they can be easily integrated with existing applications. Information in the label, particularly the metadata can be indexed for additional functionality. The index can be searchable. Search results point back to the label and to the document it associates with. The general index can be the basis of a portal for content. This permits very flexible searching and distribution of content within a DRM system. Also, rights can be delegated. For example, a publisher can give a distributor limited distribution for content merely by assigning the publishers label is to the distributor, but with limitations.
While a preferred embodiment of the invention has been described in detail above, it should be recognized that other forms, alternatives, modifications, versions and variations of the invention are equally operative and would be apparent to those skilled in the art. The disclosure is not intended to limit the invention to any particular embodiment, and is intended to embrace all such forms, alternatives, modifications, versions and variations. Accordingly, the true scope of the invention is defined by the appended claims and legal equivalents. | A method and an apparatus for specifying and editing rights associated with a content includes a general model that comprehends rights specification at different levels of the content life cycle. The rights specification includes content association, and the protection of the content is a byproduct of the content and rights association. The general model includes a rights component, a conditions component, a rights offer component, and a rights label component. The rights offers specify the relationship between rights and conditions. The rights labels are collections of the offers. | 8 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 12/766,961, filed Apr. 26, 2010, now U.S. Pat. No. 8,197,910, which claims priority to U.S. Provisional Patent Application No. 61/172,909, filed Apr. 27, 2009, the entire contents of these disclosures being incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to methods for producing synthetic surfaces that mimic collagen coated surfaces as well as surfaces prepared by such methods.
BACKGROUND OF THE INVENTION
Collagen coated surfaces have been widely used in cell culture to promote attachment of fastidious cells, including primary cells such as hepatocytes and keratinocytes. Generally, collagen derived from a non-human animal (e.g., rat tail) is employed to coat surfaces for cell culture. However, the use of such collagen can be problematic, for example, in human therapeutic applications. Although human collagen can be used for coating such surfaces, the cost is very high. Likewise, although surfaces coated with peptide sequences that mimic collagen coated surfaces have also been made to culture cells, the cost of producing such surfaces is relatively high and simply not suitable for large scale manufacturing. Thus, there is a need for methods to produce animal-free, synthetic, chemically defined surfaces that mimic collagen coated surfaces which are less costly than those presently available and suitable for large scale manufacturing as well as surfaces produced by such methods.
SUMMARY OF THE INVENTION
The present invention discloses methods for producing animal-free, synthetic, chemically defined surfaces that mimic collagen coated surfaces for cell culture. Advantageously, such methods not only reduce the cost and/or issues associated with animal-derived collagen but are also amenable to large scale manufacturing.
In particular, the present invention provides methods for producing a synthetic surface that mimics a collagen coated surface for cell culture comprising:
i) providing a monomer source comprising one or more organic compounds which are capable of polymerization, wherein at least one organic compound is prolinol; ii) creating a plasma of the monomer source; and iii) contacting at least a portion of a surface with the plasma to provide a plasma polymer coated surface wherein the plasma polymer coated surface mimics one or more functional characteristics of a collagen coated surface.
In addition, the present invention provides surfaces useful for cell culture produced by the methods described above.
The present invention also provides a surface for cell culture wherein at least a portion of the surface comprises a coating of prolinol.
The present invention further provides a surface for cell culture wherein at least a portion of the surface comprises a coating comprising a single type of amino acid wherein the single type of amino acid is proline.
These and other features of the invention will be better understood through a study of the following detailed description.
BRIEF DESCRIPTION OF THE FIGURE
FIG. 1 is a flowchart representing a method in accordance with the subject invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention discloses methods for producing a synthetic surface that mimics a collagen coated surface for cell culture. Likewise, the present invention provides surfaces useful for cell culture. Collagen is a triple helical coiled coil structure with a regular arrangement of amino acids in each of the helical unit. The sequence often follows the pattern Gly-Pro-Y or Gly-X-Hyp (hydroxyproline), where X and Y may be any of various amino acid residues and wherein the motif Gly-Pro-Hyp occurs frequently.
Though not meant to be limited by any theory with the subject invention, a proline-like monomer fixed or immobilized to a surface may mimic one or more functional characteristics of a collagen coated surface. Preferably, the proline-like monomer is fixed by plasma polymerization. Generally, monomers with relatively high vapor pressure are required so that a monomer can readily be introduced into the vacuum chamber as a vapor during the polymerization process. For example, monomers commonly used in plasma polymerization, such as allylamine and acrylic acid, have relatively high vapor pressure. In contrast, monomers with relatively low vapor pressure, such as amino acids, although useable, are not preferred for use in plasma polymerization.
Prolinol, a commercially available chiral amino-alcohol (e.g., D-Prolinol is available from Sigma-Aldrich under Catalog No. 81744) is a derivative of proline. As prolinol is a liquid with greater vapor pressure than the amino acid proline, prolinol is more amenable for use as a monomer source in creating a plasma for coating a surface therewith. In particular, treating a surface for cell culture by plasma polymerization of prolinol provides a synthetic surface that mimics a collagen coated surface. In fact, human hepatocytes are able to attach to a surface coated with prolinol alone without any further extracellular matrix protein coating.
For plasma polymerization, the cell culture vessels to be coated are loaded into a chamber of a plasma polymerization reactor. The chamber is then pumped down to create a vacuum. The vapor of monomer source comprising prolinol is introduced into the chamber. A radio-frequency power is then turned on to initiate the polymerization of prolinol on the surface(s) of the cell culture vessels inside the chamber.
In one embodiment, a RF excited plasma is employed for plasma polymerization. However, any method of generating a gaseous plasma may be used, for example a glow discharge or a corona discharge. For example, microwave frequencies may be employed instead of, or in addition to, RF excitation.
In one embodiment, the plasma is a pulsed plasma. Exemplary conditions for plasma polymerization wherein the plasma is pulsed include, but are not limited to, an on/off pulse of 1 ms/50 ms and an RF power of 100 W; an on/off pulse of 10 ms/100 ms and an RF power of 5 W; on/off pulse of 30 ms/100 ms and an RF power of 5 W; and on/off pulse of 5 ms/50 ms and an RF power of 100 W.
In another embodiment, the plasma is a continuous wave plasma. Exemplary conditions for plasma polymerization wherein the plasma is a continuous wave plasma include, but are not limited to, an RF power of 5 W.
Gases typically used with plasma treatment and introduced into the plasma chamber include Ar, He, Ne, He, He/H 2 , O 2 , N 2 , NH 3 , and CF 4 .
In one embodiment, prolinol is deposited onto the surface by plasma polymerization. A flowchart depicting a method for producing a synthetic surface by plasma polymerization of prolinol is shown in FIG. 1 . In one embodiment, the surface mimics one or more functional characteristics of a collagen coated surface. In one embodiment, human hepatocytes attach to the coating. In one embodiment, the coating consists essentially of prolinol.
Alternative means for coating a surface with prolinol include, but are not limited to, chemical vapor deposition or immobilization by covalent attachment to one or more carboxyl functional groups, one or more amine functional groups or a combination thereof. Notably, chemical vapor deposition is discussed in Dobkin and Zuraw (Dobkin and Zuraw (2003). Principles of Chemical Vapor Deposition. Kluwer). In one embodiment, prolinol is deposited onto the surface by chemical vapor deposition.
In another embodiment, prolinol is immobilized on the surface by covalent attachment to one or more carboxyl functional groups, one or more amine functional groups or a combination thereof. It is understood that for covalent attachment, the surface may require pre-activation such that the surface comprises one or more carboxyl functional groups, one or more amine functional groups or a combination thereof to facilitate the binding of prolinol thereto. Exemplary means of covalent immobilization of prolinol include, but are not limited to, providing a carboxyl functionalized surface (i.e., wherein the carboxyl groups are activated) using carbodiimide chemistry (e.g., EDC/NHS) followed by linking of prolinol to such surface through an amine reaction with the NHS groups on the surface. Alternatively, covalent immobilization may be achieved by providing an aldehyde functionalized surface followed by linking prolinol to such surface through an amine reaction with the aldehyde groups on the surface through Schiff base formation followed by stabilization of the Schiff base through sodium borohydride reduction.
Similarly, though not meant to be limited by theory with the subject invention, a single type of amino acid, e.g., proline, fixed or immobilized to a surface may mimic one or more functional characteristics of a collagen coated surface. Notably, proline makes up about 9% of collagen.
In one embodiment, proline is immobilized by covalent attachment to one or more carboxyl functional groups, one or more amine functional groups or a combination of two or more thereof. In one embodiment, the surface mimics one or more functional characteristics of a collagen coated surface. In one embodiment, human hepatocytes attach to the coating. In one embodiment, the coating consists essentially of proline.
Exemplary means for coating a surface with proline include, but are not limited to, covalent attachment to one or more carboxyl functional groups, one or more amine functional groups or a combination thereof. It is understood that for covalent attachment, the surface may require pre-activation such that the surface comprises one or more carboxyl functional groups, one or more amine functional groups or a combination thereof to facilitate the binding of proline thereto.
Similar to covalent immobilization of prolinol, exemplary means of covalent immobilization of proline include, but are not limited to, providing a carboxyl functionalized surface (i.e., wherein the carboxyl groups are activated) using carbodiimide chemistry (e.g., EDC/NHS) followed by linking of proline to such surface through an amine reaction with the NHS groups on the surface. Alternatively, covalent immobilization may be achieved by providing an aldehyde functionalized surface followed by linking proline to such surface through an amine reaction with the aldehyde groups on the surface through Schiff base formation followed by stabilization of the Schiff base through sodium borohydride reduction.
In one embodiment, the surface is a multiwell plate, a dish, or a flask. In one embodiment, the monomer source consists essentially of prolinol.
The phrase “mimics one or more functional characteristics of a collagen coated surface” as used herein with reference to a surface coated with prolinol or proline includes but is not limited to functional characteristics of collagen that includes attachment of cells to a collagen coated surface. For example, the attachment of human hepatocytes to a collagen coated surface. In one embodiment, one or more functional characteristics of a collagen coated surface comprises attachment by human hepatocytes.
EXAMPLE A
To explore the ability of the prolinol-coated surface to mimic one or more functional characteristics of a collagen coated surface, human hepatocytes were seeded and monitored on both collagen-coated and prolinol-coated surfaces under the same culture conditions. In brief, cryopreserved hepatocytes were removed from liquid nitrogen storage and immediately placed in a 37° C. waterbath until the cells were nearly thawed. The contents were then transferred to 50 mls of pre-warmed ISOM's Seeding Media. The tubes were centrifuged in a Low-speed centrifuge at 50×g for 5 minutes at room temperature. The supernatant fluid was aspirated and discarded. The cell pellet was resuspended in 1-2 mLs of ISOM's Seeding Media. Cells were counted and then diluted to a density of 10 6 cells/ml ISOM's Seeding Media. Cells were seeded at a density of 4×10 5 cells/well (i.e., a volume of 400 mL/well of 10 6 cells/mL) onto a 24-well plate. Specifically, a prolinol coated or Collagen Type I coated plate. The plates were placed in an incubator at 37° C. with 5% CO 2 for about 4 hrs. After such time, the ISOM's Seeding Media was aspirated and cells were fed with 400 μL/well of HepatoSTIM™ media (BD, Catalog #355056). Hepatocyte cell attachment was observed after 24 hours.
In addition, cell attachment and spreading on the surfaces were analyzed and microscopic images taken following several days of cell culture. Notably, human hepatocyte attachment to the prolinol-coated surface is similar to that observed for a collagen-coated surface. Moreover, it should be noted that human hepatocytes attached to the prolinol-coated surface without any further extracellular matrix protein coating. | The present invention discloses methods for producing synthetic surfaces that mimic collagen coated surfaces for cell culture comprising: providing a monomer source comprising one or more organic compounds which are capable of polymerization, wherein at least one organic compound is prolinol; creating a plasma of said monomer source; and contacting at least a portion of a surface with the plasma to provide a plasma polymer coated surface. Advantageously, such methods provide an animal-free, synthetic, chemically defined surface that mimics a collagen coated surface for cell culture. Advantageously, such methods not only reduce the cost and/or issues associated with animal-derived collagen but are also amenable to large scale manufacturing. | 8 |
This application is a continuation of application Ser. No. 813,455, filed 12/26/85 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method of characterizing 3-dimensional flaws of general shape with ultrasound through the use of 2-dimensional tomographic image reconstructions.
By employing the current state-of-the-art ultrasound inspection techniques it is not yet feasible to determine the identity, shape, and orientation of a flaw if its size is smaller than the ultrasound beam diameter. For such a small flaw the composition and geometrical parameters are frequently estimated from their acoustic scattering pattern. In the three-dimensional inverse Born Approximation the back-scattered amplitude A(ω,Ω) of plane acoustic wave incident on an isotropic homogenous flaw in an isotropic homogenous medium can be written in the form:
A(ω, Ω)=ω.sup.2 F({μ}) S(2ω/v,Ω) (1)
where F{μ} is a function of {μ} which denotes collectively the material parameters of the medium and the flaw, and S(k, Ω) is equal to the Fourier transform of the characteristic function ρ(r) of the flaw in the direction Ω of the incident plane wave (see Rose, J. H. and Krumhansl, J. A., J. Appl. Phys. 50 (1979) 2951, 52). Here the characteristic function ρ(r) specifies the flaw shape and is defined as equal to 1 inside the flaw and equal to 0 outside. With the substitution k=ω/v and rearranging, equation (1) can be written in the form
S(k,Ω)=4A(kv/2,Ω)/[k.sup.2 v.sup.2 F({μ)] (2 )
In other words an ultrasonic inspection of a flaw at an angle Ω yields a line of Fourier components of the characteristic function ρ(r) of the flaw, with the line oriented in the same direction Ω in the Fourier space and passing through the origin. This situation is illustrated in FIG. 1, where (x, y, z) denotes spatial coordinates in object space and (k x , k y , k z ) denotes spatial frequency coordinates in Fourier space. Therefore inspecting the flaw at all angles in a half space will yield all the Fourier components of ρ(r), and from these Fourier components ρ(r) can be reconstructed through 3-dimensional inverse Fourier transformation. The material parameters of the flaw can be determined from pitch catch measurements if desired (see Rose, J. H., and Richardson, J. M., J. Nondestr. Eval., 3 (1982) 45.)
Thus in order to characterize the flaw one has to inspect it from all 4π angles in 3 dimensions and perform an inverse 3-dimensional Fourier transform. Such a procedure involves a number of difficulties: (1) a large amount of data to take and process; (2) some angles may not be accessible to inspection; (3) complications associated with 3-dimensional image reconstructions, such as 3-dimensional interpolation, long computing time, etc. For these reasons the method is usually simplified and restricted to characterize symmetrically shaped flaws, which can be characterized by using only a small number of pulse echoes. This simplified procedure is known as the 1-dimensional inverse Born Approximation (see Rose, J. H. et al, "Inversion of Ultrasonic Scattering Data", Acoustic, Electromagnetic and Elastic Wave Scattering, V. V. Varadan and V. K. Varadan (Eds.), Pergamon, 1980). Though the procedure is simple, it cannot be applied to characterize flaws of more general shape.
SUMMARY OF THE INVENTION
An object of the invention is to develop a method to simplify the problem of characterizing 3-dimensional flaws of general shape with ultrasound by reducing it to a series of 2-dimensional tomographic image reconstructions. A standard computerized tomography (CT) algorithm is then used to get the 3-D shape.
Another object is to determine the size and shape of relatively small, non-symmetrically shaped flaws in an object by a simplified method that eliminates the drawbacks associated with 3-dimensional image reconstructions.
The improved method of characterizing 3-dimensional flaws of general shape with ultrasound is as follows. Pulse echo measurements are taken and return echo waveforms are acquired using broadband pulses of ultrasound that are incident on the flaw at many angles in a plane. The time Fourier transform of each pulse echo waveform gives the corresponding line of Fourier components, as mentioned above. Hence combining the inspections from many angles yields a plane of Fourier components of the characteristic function which specifies the shape of the flaw. From these Fourier components the 2-dimensional projection image is reconstructed. Then the plane on which the pulse echo measurements are made is rotated, and the foregoing steps are repeated; a plurality of 2-dimensional projection images are produced. The 3-dimensional flaw shape is reconstructed from the 2-dimensional projection images through a 3-D reconstruction process. If the flaw shape is not too irregular or fine details of the shape are not of interest, only a few projection images suffice to characterize the flaw.
Two implementations of the method are given. The first comprises deriving, from each line of Fourier components of the characteristic function, the spatial Fourier components of the flaw shape. A 1-dimensional inverse Fourier transform is then performed, line by line, to yield 1-dimensional projections of the 2-dimensional projection image. From the 1-dimensional projections the 2-dimensional projection image is reconstructed through a 2-D reconstruction.
The second implementation comprises angularly orienting and superimposing the lines of spatial Fourier components of the flaw shape. From the 2-D Fourier components the 2-dimensional projection image is reconstructed through a 2-D inverse Fourier transformation.
There are several advantages of the improved flaw characterization method. Among these are that it saves a lot of measurement time and computing time. In most cases, better image quality is achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
Figs. 1a and 1b (prior art) illustrate a pulse echo reflected from a flaw located at the origin, and the line of Fourier components calculated from it.
FIGS. 2a and 2b illustrate combining the pulse echo inspections from many angles to obtain many lines of Fourier components in Fourier space.
FIG. 3 shows a 3-dimensional flaw and 2-dimensional and 1-dimensional projected images.
FIG. 4 illustrates 2-dimensional image reconstruction from projections.
FIG. 5 shows one embodiment of an improved system to locate and inspect flaws by the method of this invention.
FIG. 6 shows graphically the complete procedure for reconstructing a 2-dimensional projection from pulse echoes.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 2a and 2b, let inspections be performed at all πangles in the x-y plane with the flaw 10 located at the origin. Only five transmitting and receiving transducers T and pulse echoes P are shown; the object containing the flaw is moved to scan over 180° Broadband narrow pulses are used to achieve good high frequency resolution; a single pulse gives a line of Fourier components. The time Fourier transform of each pulse waveform, after dividing by the Fourier transform of the pulse shape of the transducer pule shape (deconvolution), and dividing by k 2 . gives the corresponding line of Fourier components S(k) of ρ(r) in the Fourier space, as seen in Fig. 1b. Hence combining the inspections from all angles in the x-y plane, one obtains all lines of Fourier components 11 of ρ(r) lying in the k x -k y plane in the Fourier space.
The projection p z (x,y) of ρ(r) in the z direction is defined by the equation:
p.sub.z (x,y)=∫ρ(x,y,z) dz (3)
As illustrated in FIG. 3, the projection p z (x,y) or 2-dimensional projected image 12 represents the 2-dimensional shadow or silhouette of the 3-dimensional object viewed in the z direction. Now the Fourier components of ρ(r) in the k.sub. -k y plane can be viewed as the 2-dimensional Fourier transform of the projection ρ z (x,y) in the z direction: ##EQU1## where S (k x , k y , k z ) is the Fourier transform of the arbitrary 3-dimensional function (x, y, z). Hence from the plane of Fourier components the projection p z (x, y) can be reconstructed through 2-dimensional inverse Fourier transformation. In a similar manner the 2-dimensional projection of ρ(r)in any azimuthal direction can be reconstructed from the corresponding plane of Fourier components obtained from the echo waveforms. If there are missing Fourier components, they can be recovered by using the 2-dimensional version of the limited-angle reconstruction techniques discussed in the published paper by the inventor and V. PerezMendez, J. Opt. Soc. Am. 71 (1981) 582-592.
The waveforms should be normalized before attempting image reconstruction, because the magnitude of the pulse echo waveforms depends on such variables as the distance between the transducer and the flaw, the transmission coefficient at the object medium/water interface, and the solid angle subtended by the projection of the transducer area on the interface at the flaw, all of which usually change with the inspection angle. Normalization can be achieved by multiplying each deconvolved waveform by the reciprocal of the total area of the positive portion of the waveform or, equivalently, by the reciprocal of the value of the zeroth frequency component of the Fourier transform of the waveform.
The principle of the reconstruction of a 2-dimensional function p z (x,y), 15, from its 1-dimensional projections 13 is graphically illustrated in FIG. 4. By virtue of the projection theorem in computerized tomography, the Fourier transform of each 1-dimensional projection gives rise to a line of Fourier components 14 in the Fourier space. Therefore the entire 2-dimensional transform of p z (x,y) can be obtained by combining all of these lines of Fourier components, and p z (x,y) itself, 2-dimensional projection image 15, can be reconstructed by 2-dimensional inverse Fourier transformation.
The physical meaning of the 1-dimensional projection 13 can be seen in FIG. 3, where P z is the projection along the z direction and P y is the projection along the y direction. The function p yz (x) is defined which is the 1-dimensional projection or projected image of ρ(x,y,z) onto the x axis; P yz (x) can be considered as the 1-dimensional projection of the 2-dimensional function p z (x,y) projected along the y direction onto the x axis. Given enough of these projections of p z (x,y) at all angles from o to π in the x-y plane, the function p z (x,y) itself can be reconstructed uniquely. This is the well known result in computerized tomography. That only projections from o to π instead of o to 2π are needed is due to the inversion symmetry of the projection operation, i.e. the projection at angle θ is the same as the projection at angle θ+π. The reconstruction of p z (x,y) from its projections can be accomplished using object-space reconstruction algorithms such as filtered back projection, or it can proceed in Fourier space after taking the transform of the projections. The 1-dimensional function previously was used to derive a 1-dimensional projection, or, if there are many, to perform a 3-dimensional image reconstruction. This invention recognizes that the 1-dimensional functions in one plane can be used to perform a 2-dimensional image reconstruction.
It has been shown that p z (x,y) is the 2-dimensional image of the flaw shape projected along the z direction onto the x-y plane. The numerical value of the function is a measure of the thickness of the 3-dimensional object at each lateral position (x,y), and its shape represents the shadow or silhouette of the object viewed in the z direction. By rotating the plane on which the pulse echo measurements are made, one can obtain the 2-dimensional projection of ρ(r) in other directions. If the shape of the flaw is not too irregular or if the fine details of the shape are not of interest, only a few of these projection images suffice to characterize the flaw. Only a few views of the flaw (less than 10) are needed to give an overall idea of its shape and size, and one needs only to inspect the flaw in the planes perpendicular to the views of interest. Of course, if enough of these 2-dimensional projections are measured ρ(r) itself can be reconstructed completely.
There are several advantages in reducing the flaw characterization problem from reconstructing the 3-dimensional flaw shape to reconstructing the individual 2-dimensional projections of the flaw. First of all, it saves a lot of measurement time and computing time. As mentioned before, a small number of 2-dimensional projections usually suffice to give a fairly good estimate of the 3-dimensional flaw shape. Therefore only measurements in those planes are needed. In contrast, with 3-dimensional image reconstruction, inspections at all 4π steradians are always needed even if only a few views are actually of interest.
The second advantage of reducing the 3-dimensional image reconstruction to 2-dimensional image reconstruction is that in most cases better image quality can be achieved. It often happens that the flaw cannot be inspected in some angular range, and therefore the corresponding Fourier components at those angles are not available in reconstructing the flaw shape. The quality of the reconstructed image will be degraded if the reconstruction is performed in a 3-dimensional manner involving all the 4π Fourier components in the 3-dimensional Fourier space. In the reconstruction of a 2-dimensional projection of the flaw shape, however, only the Fourier components on the corresponding plane in the Fourier space are needed. Therefore it is possible to reconstruct some 2-dimensional projections without loss of information if, for these projection images, inspection is accessible at all the 2π angles in the corresponding inspection plane.
The third advantage is that if the flaw shape is convex, the reconstructions can be done much easier. In general, all the details in the pulse echo waveforms are needed in reconstructing the 2-dimensional projection images. But if the 3-dimensional flaw shape is convex, it can be shown that its 2-dimensional projection images are also convex. In this case these projection images can be reconstructed using only the shape of the pulse echo waveforms, their magnitude scale becomes unimportant. This simplified reconstruction procedure is especially advantageous in ultrasound inspection since the pulse echoes at different angles are not on the same scale, as mentioned before.
Even if the flaw shape is not convex and therefore its 2-dimensional projections may not be convex, using only the shape of the waveforms one can reconstruct the convex hull of the 2-dimensional projections. For a flaw not too irregular in shape, the convex hulls of its 2-dimensional projections are fairly good approximations for the projections themselves.
FIG. 5 shows a practical realization of the invention. An object 16 containing the flaw 10, typically a metallic workpiece having a void or inclusion, is inspected in a water bath 17. A number of matching unfocused transducers T (5 shown in the figure) are used to locate and inspect flaws. The transducers are positioned on a plane. The positions of the transducers in the plane can be adjusted to view the object at different polar angles by means of mechanical arms which can move the transducers around and tilt them at different angles. The azimuthal angle of the plane can also be varied by means of the same mechanical arms. The object 16 is rotated in order to inspect another plane. The movements of the mechanical arms are controlled by a movement controller 19 which is a microprocessor controlled by signals sent from the signal processing computer 20. After the transducers 18 are stabilized in each position and orientation the movement controller 19 sends a pulse command signal to start a pulser-receiver 21 whose pulses activate transducers T. The return echoes from the flaw 10 are detected by the transducers, sent to the pulser-receiver 21, and then to a transient recorder 22 which digitizes the analog waveforms for input to the signal processing computer 20. In the computer the digitized pulse echo waveforms are processed to yield the 2-dimensional projection images of the flaw shape.
The complete procedure and two alternative methods for reconstructing p z (x,y), the reconstructed 2-dimensional image, from the pulse echoes are graphically illustrated in FIG. 6. In the first block 23, pulse echo measurements using broadband incident pulses are taken at each incident angle in the x-y plane. Only three transducers an pulse echoes are used to explain the principle. The analog waveforms are illustrated in block 24. Each waveform is subjected to a 1-dimensional Fourier transform to yield the corresponding line of Fourier components in the Fourier space. Each line of Fourier components is normalized by multiplying each Fourier component by the reciprocal of the corresponding Fourier component of the waveform backscattered from the front surface of the medium, and by the reciprocal of the zeroth frequency Fourier component on the line. The purpose for the latter is to correct for the difference in the magnitude scale of the different pulse echos. The final result obtained (block 25) is the scattering amplitude A(ω,Ω) in equation (1). This is the measured quantity. The factor S (ω,Ω) is obtained from A(ω, Ω) by dividing by ω 2 . Alternatively, referring to equation (2), A(ω,Ω) is divided by k 2 , a quantity proportional to the square of the angular frequency (ω) of the incident ultrasonic wave, to obtain the spatial Fourier components S(k, Ω) of the flaw shape as seen in block 26.
At this point there are two alternatives, diagramed in blocks 27a and 27b to obtain the 2-dimensional projection image 15 and p z (x,y). The first method processes one line at a time, or line by line, as is typically done in CT imaging. A 1-dimensional inverse Fourier transform is performed on every line of spatial Fourier components and gives the quantities p yz (x), the 1-dimensional projected image. From these 1-dimensional projections (see block 28) the quantity p z (x,y), the 2-dimensional projection image 15 of the flaw shape, is reconstructed, using object-space reconstruction algorithms.
The second method, illustrated by block 27b, comprises angularly orienting and superimposing the quantities S(k, Ω), the lines of spatial Fourier components, to obtain a plane of 2-D Fourier components. A 2-dimensional inverse Fourier transformation yields the 2-dimensional projection image 15 of the flaw shape. The final steps are to acquire a plurality of 2-dimensional projection images by rotating the plane on which pulse echo measurements are made and repeating the foregoing procedures. Referring to block 29, the 3-dimensional flaw shape 30 is reconstructed from these 2-dimensional projection images through a 3-dimensional reconstruction process.
Since the invention is capable of both reconstructing 3-dimensional flaws of general shape and yielding the material parameters of flaws of general shape, it has a wide range of applications in industrial ultrasound inspection. Among other things, it can be applied to identify flaws in the critical parts in nuclear reactors, aircraft engines, turbines, and other high-cost equipment.
Further explanation is given in "3-Dimensional Flaw Characterizations Through 2-Dimensional Image Reconstructions", Review of Progress in Nondestructive Evaluation, Vol. 5, Plenum Press, pp. 541-553. The same technical paper is published as TIS Report No. 85CRD199, Nov. 1985, General Electric Co., Corporate Research and Development, Schenectady, N.Y. 12345.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention. | This ultrasound imspection method using the Born approximation simplifies the problem of characterizing 3-dimensional flaws of general shape by reducing it to a series of 2-dimensional tomographic image reconstructions. The reconstructed 2-dimensional images represent the 2-dimensional projections or shadows of the 3-dimensional flaw characteristic function which specifies the shape of the flaw. Each projection image is reconstructed independently using well developed computerized tomography techniques. If the shape of the flow is not too irregular or fine details are not of interest, only a few of these projection images are needed. The 3-dimensional flaw shape is reconstructed from the 2-dimensional projection images through a 3-D reconstruction process. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This disclosure is a continuation U.S. patent application Ser. No. 13/587,390 (now U.S. Pat. No. 8,787,293), filed Aug. 16, 2012 which claims the benefit of Provisional Patent Application Ser. No. 61/530,220, filed Sep. 1, 2011, entitled “ACL Packets Size Spoofing for Coexistence TDM solutions,” the disclosure thereof incorporated by reference herein in its entirety.
FIELD
The present disclosure relates generally to the field of wireless communication. More particularly, the present disclosure relates to avoiding interference between different wireless communication technologies that use adjacent or overlapping frequency bands.
BACKGROUND
The popularity of multiple wireless communication technologies for handheld platforms has created a need to integrate wireless communication technologies on a single wireless communication device. However, frequency bands of some of these technologies are close enough to result in interference. For example, an un-licensed 2.4 GHz Industrial, Scientific and Medical (ISM) frequency band is adjacent to some of the bands used by Mobile Wireless Standards (MWS) technologies to result in adjacent channel interference. In many electronic devices such as smartphones, both ISM and MWS technologies are implemented in a same device. For example, a smartphone may employ LTE (Long Term Evolution) for transmitting and receiving data, and Bluetooth for headsets. LTE transmissions from the smartphone will cause adjacent channel interference with incoming Bluetooth signals. Similarly, Bluetooth from the smartphone will cause adjacent channel interference with incoming LTE signals. This adjacent channel interference can significantly degrade performance not only at the smartphone, but also at connected MWS base stations.
SUMMARY
In general, in one aspect, an embodiment features an apparatus comprising: a Long Term Evolution (LTE) transceiver configured to transmit and receive wireless LTE signals according to an LTE schedule, and to provide LTE schedule information that represents the LTE schedule; and a Bluetooth transceiver configured to transmit and receive wireless Bluetooth signals according to a Bluetooth schedule having a plurality of Bluetooth schedule slots, wherein the wireless Bluetooth signals represent Bluetooth Asynchronous Connection-oriented [logical transport] (ACL) packets; a Bluetooth packetizer configured to generate a Bluetooth ACL packet; and a Bluetooth scheduler configured to select a spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet based on the LTE schedule information, wherein M is a positive integer; wherein the Bluetooth packetizer is further configured to select a Bluetooth ACL packet type based on the spoofed number M of the Bluetooth schedule slots, and to indicate the selected Bluetooth ACL packet type in a type field of the Bluetooth ACL packet, prior to the Bluetooth transceiver transmitting the wireless Bluetooth signals representing the Bluetooth ACL packet.
Embodiments of the apparatus can include one or more of the following features. In some embodiments, the Bluetooth ACL packet generated by the Bluetooth packetizer requires only N of the Bluetooth schedule slots, wherein N is a positive integer, and wherein M>N; and the Bluetooth scheduler is further configured to determine the spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet based on the LTE schedule information and the integer N. In some embodiments, the LTE schedule includes uplink time slots and downlink time slots, wherein the LTE transceiver is allowed to transmit the wireless LTE signals only during the uplink time slots; the Bluetooth schedule slots include transmit time slots and receive time slots, wherein the Bluetooth transceiver is allowed to begin transmitting each of the wireless Bluetooth signals only during one of the transmit time slots; and the Bluetooth scheduler is further configured to determine the spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet so that a corresponding reply Bluetooth ACL packet is received during one of the downlink time slots. In some embodiments, the LTE schedule information represents a duration of the uplink time slots, a duration of the downlink time slots, and a frame synchronization indicator. In some embodiments, M=3 or 5. In some embodiments, the Bluetooth scheduler is further configured to determine a time for transmitting the wireless Bluetooth signals representing the Bluetooth ACL packet based on an alignment between the time slots of the LTE schedule and the time slots of the Bluetooth schedule. Some embodiments comprise one or more integrated circuits comprising the apparatus. Some embodiments comprise an electronic device comprising the apparatus.
In general, in one aspect, an embodiment features a method for an electronic device, the method comprising: transmitting and receiving wireless Long Term Evolution (LTE) signals according to an LTE schedule; transmitting and receiving wireless Bluetooth signals according to a Bluetooth schedule having a plurality of Bluetooth schedule slots, wherein the wireless Bluetooth signals represent Bluetooth Asynchronous Connection-oriented [logical transport] (ACL) packets; generating a Bluetooth ACL packet; selecting a spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet based on information representing the LTE schedule, wherein M is a positive integer; selecting a Bluetooth ACL packet type based on the spoofed number M of the Bluetooth schedule slots; and indicating the selected Bluetooth ACL packet type in a type field of the Bluetooth ACL packet prior to transmitting the wireless Bluetooth signals representing the Bluetooth ACL packet.
Embodiments of the method can include one or more of the following features. In some embodiments, wherein the Bluetooth ACL packet requires only N of the Bluetooth schedule slots, wherein N is a positive integer, the method further comprises: determining the spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet based on the LTE schedule information and the integer N, wherein M>N. In some embodiments, the LTE schedule includes uplink time slots and downlink time slots, wherein the electronic device is allowed to transmit the wireless LTE signals only during the uplink time slots; the Bluetooth schedule slots include transmit time slots and receive time slots, wherein the electronic device is allowed to begin transmitting each of the wireless Bluetooth signals only during one of the transmit time slots; and the method further comprises determining the spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet so that a corresponding reply Bluetooth ACL packet is received during one of the downlink time slots. In some embodiments, the LTE schedule information represents a duration of the uplink time slots, a duration of the downlink time slots, and a frame synchronization indicator. In some embodiments, M=3 or 5. Some embodiments comprise determining a time for transmitting the wireless Bluetooth signals representing the Bluetooth ACL packet based on an alignment between the time slots of the LTE schedule and the time slots of the Bluetooth schedule.
In general, in one aspect, an embodiment features computer-readable media embodying instructions executable by a computer in an electronic device to perform functions comprising: transmitting and receiving wireless Long Term Evolution (LTE) signals according to an LTE schedule; transmitting and receiving wireless Bluetooth signals according to a Bluetooth schedule having a plurality of Bluetooth schedule slots, wherein the wireless Bluetooth signals represent Bluetooth Asynchronous Connection-oriented [logical transport] (ACL) packets; generating a Bluetooth ACL packet; selecting a spoofed number M of Bluetooth schedule slots for the Bluetooth ACL packet based on information representing the LTE schedule, wherein M is a positive integer; selecting a Bluetooth ACL packet type based on the spoofed number M of the Bluetooth schedule slots; and indicating the selected Bluetooth ACL packet type in a type field of the Bluetooth ACL packet prior to transmitting the wireless Bluetooth signals representing the Bluetooth ACL packet.
Embodiments of the computer-readable media can include one or more of the following features. In some embodiments, the Bluetooth ACL packet requires only N of the Bluetooth schedule slots, wherein N is a positive integer, and wherein the functions further comprise: determining the spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet based on the LTE schedule information and the integer N, wherein M>N. In some embodiments, the LTE schedule includes uplink time slots and downlink time slots, wherein the electronic device is allowed to transmit the wireless LTE signals only during the uplink time slots; the Bluetooth schedule slots include transmit time slots and receive time slots, wherein the electronic device is allowed to begin transmitting each of the wireless Bluetooth signals only during one of the transmit time slots; and wherein the functions further comprise determining the spoofed number M of the Bluetooth schedule slots for the Bluetooth ACL packet so that a corresponding reply Bluetooth ACL packet is received during one of the downlink time slots. In some embodiments, the LTE schedule information represents a duration of the uplink time slots, a duration of the downlink time slots, and a frame synchronization indicator. In some embodiments, M=3 or 5. In some embodiments, the functions further comprise: determining a time for transmitting the wireless Bluetooth signals representing the Bluetooth ACL packet based on an alignment between the time slots of the LTE schedule and the time slots of the Bluetooth schedule.
The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
FIG. 1 shows elements of a user equipment according to one embodiment.
FIG. 2 shows a timeline for conventional Bluetooth and LTE schedules with frame alignment.
FIG. 3 shows a timeline for conventional Bluetooth and LTE schedules with no frame alignment.
FIG. 4 shows a timeline for a coexistence solution with no frame alignment according to one embodiment.
FIG. 5 shows a timeline for a conventional coexistence solution with frame alignment.
FIG. 6 shows a timeline for a coexistence solution with frame alignment according to one embodiment.
FIG. 7 shows a process for the user equipment of FIG. 1 according to one embodiment.
FIG. 8 shows the packet format of a Bluetooth Asynchronous Connection-oriented [logical transport] (ACL) packet.
FIG. 9 shows the format of the payload field of FIG. 8 .
FIG. 10 shows the format of the payload header field of FIG. 9 for a Bluetooth ACL packet.
The leading digit(s) of each reference numeral used in this specification indicates the number of the drawing in which the reference numeral first appears.
DETAILED DESCRIPTION
Embodiments of the present disclosure provide coexistence in an electronic device, also referred to herein as “user equipment,” having both a Long Term Evolution (LTE) radio and a Bluetooth radio. According to the described embodiments, the Bluetooth radio modifies (that is, “spoofs”) a packet type of a transmitted Bluetooth Asynchronous Connection-oriented [logical transport] (ACL) packet. Because the packet type indicates a number of Bluetooth schedule slots required to transmit the packet, spoofing the packet type can be used to shift an arrival time of a corresponding reply packet to a time when the arriving packet will not interfere with reception of LTE signals by the co-located LTE radio. While described in terms of an LTE radio, the disclosed embodiments apply to other Mobile Wireless Standards (MWS) radios such as Worldwide Interoperability for Microwave Access (WiMAX) and the like.
FIG. 1 shows elements of a user equipment 100 according to one embodiment. Although in the described embodiments, elements of the user equipment 100 are presented in one arrangement, other embodiments may feature other arrangements. For example, elements of the user equipment 100 can be implemented in hardware, software, or combinations thereof. The user equipment 100 can be implemented as any sort of electronic device capable of performing functions described herein. For example, the user equipment 100 can be implemented as a smartphone, tablet computer, or the like. Elements of user equipment 100 can be implemented as one or more integrated circuits.
Referring to FIG. 1 , the user equipment 100 includes an LTE radio 102 and a Bluetooth radio 104 . The LTE radio 102 includes an LTE transceiver 106 , and stores an LTE schedule 108 . The LTE transceiver 106 transceives (that is, transmits and receives) wireless LTE signals 110 according to the LTE schedule 108 using one or more antennas 112 . The Bluetooth radio 104 includes a Bluetooth transceiver 114 , a Bluetooth packetizer 116 , and a Bluetooth scheduler 118 . The Bluetooth scheduler 118 stores a Bluetooth schedule 120 . The Bluetooth transceiver 114 transceives wireless Bluetooth signals 122 according to the Bluetooth schedule 120 using one or more antennas 124 . In some embodiments, one or more of the antennas 112 , 124 can be combined. The Bluetooth scheduler 118 can be implemented as a processor. The LTE radio 102 and the Bluetooth radio 104 can be implemented as one or more integrated circuits. The LTE radio 102 provides LTE schedule information 126 to the Bluetooth radio 104 .
In some cases, it is easy for the Bluetooth scheduler 118 to find time for Bluetooth ACL transmission, for example when there is frame alignment between the LTE schedule and the Bluetooth schedule. FIG. 2 shows a timeline 200 for conventional Bluetooth and LTE schedules with frame alignment. Referring to FIG. 2 , the Bluetooth schedule is shown at 202 , and consists of alternating receive time slots Rx and transmit time slots Tx. The Bluetooth transceiver 114 is allowed to begin transmitting the wireless Bluetooth signals 122 only during a transmit time slot Tx. All receive time slots Rx and transmit time slots Tx have the same duration 625 us. The LTE schedule is shown at 204 , and consists of alternating downlink time slots (DL) and uplink time slots (UL). The LTE transceiver 106 is allowed to transmit the wireless LTE signals 110 only during the uplink time slots UL. In the example of FIG. 2 , a duration of each LTE downlink time slot DL is 2.7865 ms, and a duration of each LTE uplink time slot UL is 2.2145 ms.
Frame alignments between the Bluetooth schedule 202 and the LTE schedule 204 are indicated at 212 A and 212 B. Frame alignments 212 occur where a boundary between a Bluetooth transmit time slot Tx and a following Bluetooth receive time slot Rx occurs at the same time as a boundary between an LTE uplink time slot UL and a following LTE downlink time slot DL. In the example of FIG. 2 , frame alignment 212 A occurs at a boundary between Bluetooth time slots Tx2 and Rx3 and a boundary between LTE time slots ULa and DLb. Frame alignment 212 B occurs at a boundary between Bluetooth time slots Tx6 and Rx7 and a boundary between LTE time slots ULb and DLc. Frame alignments can also occur where the boundary between a Bluetooth receive time slot Rx and the following Bluetooth transmit time slot Tx occurs at the same time as a boundary between an LTE downlink time slot DL and a following LTE uplink time slot UL. Frame alignment can sometimes be obtained by adjusting a phase of a Bluetooth clock in accordance with the LTE schedule 108 .
In the described embodiments, the Bluetooth transceiver 114 acts as a Bluetooth master device. In FIG. 2 , the Bluetooth ACL packets (ACL Tx) transmitted by the Bluetooth transceiver 114 to a Bluetooth slave device are shown at 206 , and the Bluetooth ACL packets (ACL Rx) received by the Bluetooth transceiver 114 from a Bluetooth slave device are shown at 208 . A Bluetooth ACL packet can occupy 1, 3, or 5 Bluetooth time slots. A Bluetooth ACL packet that occupies 3 or 5 Bluetooth time slots is referred to as a “multi-slot” packet. Packets sent by the Bluetooth master must begin in a transmit time slot Tx. Packets sent by the Bluetooth slave must begin in a receive time slot Rx. A Bluetooth slave device sends Bluetooth packets only in response to a Bluetooth packet transmitted by the master device, and starting only in the time slot following the received packet.
In the example of FIG. 2 , these conditions are easy to satisfy thanks to the frame alignments 212 . The Bluetooth scheduler 118 can simply schedule a packet to be transmitted so transmission of the packet ends at the frame alignment 212 . Then the reply packet is sent by the Bluetooth slave right after the frame alignment 212 . For example, in FIG. 2 , the Bluetooth transceiver 114 transmits a three-slot packet ACL Txa right before the frame alignment 212 A, thereby causing the Bluetooth slave to transmit a reply packet ACL Rxa right after the frame alignment 212 A. Similarly, the Bluetooth transceiver 114 transmits a one-slot packet ACL Txb right before the frame alignment 212 B, thereby causing the Bluetooth slave to transmit a reply packet ACL Rxb right after the frame alignment 212 B. In both cases, the Bluetooth packet transmissions are aligned with the LTE uplink time slots UL, and the Bluetooth packet receptions are aligned with the LTE downlink time slots DL, resulting in minimal mutual interference.
In other cases, it is difficult for the Bluetooth scheduler 118 to find time for Bluetooth ACL transmission, for example when there is no frame alignment between the LTE schedule and the Bluetooth schedule. FIG. 3 shows a timeline 300 for conventional Bluetooth and LTE schedules with no frame alignment. Referring to FIG. 3 , the Bluetooth schedule is shown at 302 , and the LTE schedule is shown at 304 . The time slot durations are the same as in FIG. 2 . In FIG. 3 , it is impossible to find any time for the Bluetooth ACL transmission, even for one-slot packets. For example, if the Bluetooth transceiver 114 sends a Bluetooth packet in time slot Tx1, the slave cannot reply in the next time slot Rx2 because an LTE uplink time slot ULa overlaps with time slot Rx2.
The described embodiments solve this problem by spoofing the packet type of the Bluetooth packets transmitted by the Bluetooth transceiver 114 . In particular, the spoofed packet type makes the packet appear longer to the Bluetooth slave than the actual packet length. This spoofing is used to shift the reply packet to an LTE downlink time slot in order to minimize mutual interference.
FIG. 4 shows a timeline 400 for a coexistence solution with no frame alignment according to one embodiment. Referring to FIG. 4 , a Bluetooth schedule is shown at 402 , and an LTE schedule is shown at 404 . The time slot durations are the same as in FIGS. 2 and 3 . The Bluetooth ACL packets (ACL Txa/b) transmitted by the Bluetooth transceiver 114 to a Bluetooth slave device are shown at 406 , and the Bluetooth ACL packets (ACL Rx) received by the Bluetooth transceiver 114 from a Bluetooth slave device are shown at 408 . The Bluetooth radio 104 employs packet type spoofing in the transmitted packets ACL Txa and ACL Txb. Each packet ACL Txa and ACL Txb includes a “Data OK” portion and an “Empty” portion. Data can be transmitted in the “Data OK” portion because the “Data OK” portion is aligned with an LTE uplink time slot ULa. However, the “Empty” portion occurs during an LTE downlink time slot where Bluetooth transmission is not allowed. But because there is no data in the “Empty” portion, no Bluetooth signals are transmitted during that time. The “Empty” portion is shown only to indicate an interval spanned by the packet type spoofing. The time of the Bluetooth slave reply packets ACL Rxa and ACL Rxb is determined by the spoofed packet type. Therefore the Bluetooth slave does not reply until after the “Empty” portion of a corresponding master packet ACL Txa and ACL Txb. In this manner the spoofed packet type can be chosen so as to shift the reply packet to an LTE downlink time slot DL.
The described embodiments can also be used in the presence of frame alignment to improve throughput compared with conventional coexistence solutions. FIG. 5 shows a timeline 500 for a conventional coexistence solution with frame alignment. Referring to FIG. 5 , the Bluetooth schedule is shown at 502 , and the LTE schedule is shown at 504 . A frame alignment between the Bluetooth schedule 502 and the LTE schedule 504 is shown at 512 . A Bluetooth ACL packet (ACL Txa) transmitted by the Bluetooth transceiver 114 to a Bluetooth slave device is shown at 506 , and the Bluetooth ACL packets (ACL Rx) received by the Bluetooth transceiver 114 from a Bluetooth slave device are shown at 508 . In the example of FIG. 5 , the Bluetooth radio 104 can send only a one-slot packet ACL Txa at frame alignment 512 .
FIG. 6 shows a timeline 600 for a coexistence solution with frame alignment according to one embodiment. Referring to FIG. 6 , the Bluetooth schedule is shown at 602 , and the LTE schedule is shown at 604 . A frame alignment between the Bluetooth schedule 602 and the LTE schedule 604 is shown at 612 . The Bluetooth scheduler 118 determines times for transmitting the wireless Bluetooth signals representing the Bluetooth ACL packet based on frame alignment 612 . A Bluetooth ACL packet (ACL Txa) transmitted by the Bluetooth transceiver 114 to a Bluetooth slave device is shown at 606 , and the Bluetooth ACL packets (ACL Rx) received by the Bluetooth transceiver 114 from the Bluetooth slave device are shown at 608 . In the example of FIG. 6 , the Bluetooth radio 104 employs packet type spoofing to send two slots of data, resulting in a two-fold throughput improvement compared with the conventional coexistence solution of FIG. 5 . In some embodiments, greater throughput multiples can be achieved.
FIG. 7 shows a process 700 for the user equipment 100 of FIG. 1 according to one embodiment. Although in the described embodiments the elements of process 700 are presented in one arrangement, other embodiments may feature other arrangements. For example, in various embodiments, some or all of the elements of process 700 can be executed in a different order, concurrently, and the like. Also some elements of process 700 may not be performed, and may not be executed immediately after each other. In addition, some or all of the elements of process 700 can be performed automatically, that is, without human intervention.
Referring to FIG. 7 , at 702 , the Bluetooth packetizer 116 generates a Bluetooth ACL packet. The Bluetooth ACL packet generated by the Bluetooth packetizer 116 requires only N Bluetooth schedule slots, where N is a positive integer. In some embodiments, the Bluetooth scheduler 118 determines the number of slots N for the Bluetooth ACL packet based on the LTE schedule information 126 provided by the LTE radio 102 . In some embodiments, the LTE schedule information 126 represents the duration of the uplink time slots UL, the duration of the downlink time slots DL, and a frame synchronization indicator that indicates the timing of the occurrence of time slots UL, DL.
At 704 , the Bluetooth scheduler 118 determines a spoofed number M of Bluetooth schedule slots for the Bluetooth ACL packet based on the LTE schedule information 126 , where M is a positive integer, and where M>N. In particular, the Bluetooth scheduler 118 selects a value of M that will shift the reply packet to an LTE downlink slot. The determination of the spoofed number M of Bluetooth schedule slots can include consideration of the required number of slots N.
At 706 , the Bluetooth packetizer 116 selects a Bluetooth ACL packet type based on the spoofed number M of the Bluetooth schedule slots. There are seven types of Bluetooth ACL packets: DM1, DH1, DM3, DH3, DM5, DH5, and AUX1. Each type indicates a number of Bluetooth schedule slots for the packet. The DM1, DH1, and AUX1 packet types indicate one Bluetooth schedule slot. The DM3 and DH3 packet types indicate three Bluetooth schedule slots. The DM5 and DH5 packet types indicate five Bluetooth schedule slots. When M=1, the Bluetooth packetizer 116 selects the DM1, DH1, or AUX1 packet type. When M=3, the Bluetooth packetizer 116 selects the DM3 or DH3 packet type. When M=5, the Bluetooth packetizer 116 selects the DM5 or DH5 packet type.
At 708 , the Bluetooth packetizer 116 indicates the selected packet type in the type field of the Bluetooth ACL packet. At 710 , the Bluetooth transceiver 114 transmits wireless Bluetooth signals 122 representing the Bluetooth ACL packet with the selected packet type in the type field. In some embodiments, the Bluetooth scheduler 118 determines the time for transmitting the wireless Bluetooth signals 122 based on a frame alignment between the time slots of the LTE schedule 108 and the time slots of the Bluetooth schedule 120 , for example as discussed with reference to FIGS. 5 and 6 .
FIG. 8 shows the packet format of a Bluetooth ACL packet 800 . Referring to FIG. 8 , the Bluetooth ACL packet 800 includes a 72-bit access code field 802 , a 54-bit header field 804 , and a payload field 806 with a length of 0 to 2745 bits.
FIG. 9 shows the format of the payload field 806 of FIG. 8 . Referring to FIG. 9 , the payload field 806 includes a payload header field 902 with a length of 8 to 16 bits, a body field 904 with a length indicated in the payload header field 902 , and a 16-bit cyclic redundancy check (CRC) code field 906 .
FIG. 10 shows the format of the payload header field 902 of FIG. 9 for a Bluetooth ACL packet. Referring to FIG. 10 , the payload header field 902 includes a 3-bit temporary address (Am_addr) field 1002 , a 4-bit Type field 1004 , a 1-bit Flow field 1006 , a 1-bit Arqn field 1008 , a 1-bit sequence number (Seqn) field 1010 , and an 8-bit header error check (HEC) field 1012 . In some embodiments, the Bluetooth packetizer 116 places the packet type, selected based on the spoofed number M of Bluetooth schedule slots, in the Type field 1004 .
Various embodiments of the present disclosure can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations thereof. Embodiments of the present disclosure can be implemented in a computer program product tangibly embodied in a computer-readable storage device for execution by a programmable processor. The described processes can be performed by a programmable processor executing a program of instructions to perform functions by operating on input data and generating output. Embodiments of the present disclosure can be implemented in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. Each computer program can be implemented in a high-level procedural or object-oriented programming language, or in assembly or machine language if desired; and in any case, the language can be a compiled or interpreted language. Suitable processors include, by way of example, both general and special purpose microprocessors. Generally, processors receive instructions and data from a read-only memory and/or a random access memory. Generally, a computer includes one or more mass storage devices for storing data files. Such devices include magnetic disks, such as internal hard disks and removable disks, magneto-optical disks; optical disks, and solid-state disks. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM disks. Any of the foregoing can be supplemented by, or incorporated in, ASICs (application-specific integrated circuits).
A number of implementations have been described. Nevertheless, various modifications may be made without departing from the scope of the disclosure. Accordingly, other implementations are within the scope of the following claims. | A wireless device including a first transceiver to communicate according to a first schedule using a first communication protocol. The first schedule includes information of uplink and downlink slots. A second transceiver communicates according to a second schedule using a second communication protocol. The second schedule includes a first number of slots for transmitting packets. A scheduler changes, based on the first schedule, the first number of slots to a second number of slots. The second number of slots is greater than the first number of slots. A packetizer selects a packet type of a first packet for transmission from the first transceiver to a remote device. The packet type indicates that the first packet requires the second number of slots for transmission and shifts transmission of a response from the remote device to one of the downlink slots to minimize interference between communications of the first and second transceivers. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to layout tools for framing squares and particularly to layout tools that have alignment mechanisms and markings, which attach to framing squares.
2. Description of the Prior Art
Framing squares are a ubiquitous tool of carpenters and other builders. This tool is used to layout rafters and stair stringers as well as many other functions. In the case of rafters and stairs, many calculations are required, depending on the type of rafter (e.g., hip rafter, valley rafter, etc.) and stairs. It takes a lot of experience to do this work properly and consistently. Once the calculations have been made, the carpenter uses the framing square to mark construction material with the lines used to cut the rafter or stair stringers. Again, care must be used to ensure that the cut lines are correct as time and material are wasted once a board has been cut improperly. Another problem with using the square is that rafters and stair stringers require many layout marks. A square, by itself, must be positioned, and aligned with the proper measurements each time a cut is made; this takes time and adds to the possibility of error.
Over the years, people have developed tools that can assist the carpenter in making these measurements and cuts. One such example is found in U.S. Pat. No. 935,067 To Taylor. This too shows a small square that has a groove cut into each major axis of the square. A straight rule, with two grooves cut in it is attached to the square and held by to fasteners that are placed through the grooves in both the rule and the square. The rule can then be positioned across the square and locked into the measured lengths so that repeated marks can be made with minimal error. The problem with this device is that it requires the square to have the grooves into which the fasteners are secured. Moreover, to use the square for other applications, the rule must be removed, which takes time. Another tool that helps is found in U.S. Pat. No. 6,070,334 to Pretsch, Jr. This design is a simple straightedge that is secured to a common framing square so that it forms a straight edge that can be abutted against a board so that the proper cut lines can be drawn. This tool is better than the Taylor device in that it can be used on a standard framing square. However, the user must make the calculations as before; thus, there is limited advantage to using this tool. Another tool is found in U.S. Pat. No. 7,197,833 to Ekern. In this design, the tool has a pair of groves cut through the tool. The framing square is slid into these grooves and placed in the proper position. Then, the tool is locked in place and the tool can be used as a straight edge. One advantage of the Ekern tool as compared to the Pretsch, Jr. tool is that, because of the body groove, the tool has a body on both the top and bottom of the square. This allows the tool to the placed against the board above or below the top surface of the board. However, as before, this tool still requires the user to calculate the angles and determine the position of the straight edge on the square as before.
BRIEF DESCRIPTION OF THE INVENTION
The instant invention overcomes these difficulties. It is an object of this invention to produce an attachment for a framing square that allows for the layout and cutting of common rafters from one pivot point by placing the tool on the framing square and directly arriving at the desired angle without making prior calculations.
It is another object of this invention to produce an attachment for a framing square that allows for the scribing angles by directly using the tool.
It is yet another object of this invention to produce an attachment for a framing square that allows for the layout and cutting of hip and valley rafters from one pivot point by placing the tool on the framing square and directly arriving at the desired angle without having to make prior calculations.
It is another object of this invention to produce an attachment for a framing square that allows for the determination of the length per foot of run from one pivot point to determine the appropriate rafter length.
It is yet another object of this invention to produce an attachment for a framing square that allows for level cuts for truss fabrication and roof framing.
It is yet another object of this invention to produce an attachment for a framing square that allows for the layout and cutting of stair stringers by placing the tool on the framing square and directly arriving at the desired angle without having to make prior calculations.
It is yet another object of this invention to produce an attachment for a framing square that allows for the use of the framing square as a Tee square.
With those objects in mind, the invention is made of a pair of straight members that are fastened together with a space therebetween. Each of the members has a pair of horizontal grooves that are aligned. A fastener is positioned within each of the grooves to lock a framing square in place once the desired setting have been determined. The tool has markings on each face that are used to establish angles for desired cuts. Using pivot points that are placed on the tool, the framing square can be set at one point and then pivoted to the desired angle using the markings on the tool without having to calculate anything. In this way, many different types of building members including: rafters, trusses and stairs can be laid out, marked and cut with minimal error and optimal efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a first embodiment of the invention.
FIG. 1 a is an enlarged view of the left side of FIG. 1 .
FIG. 1 b is an enlarged view of the right side of FIG. 1 .
FIG. 1 c is an enlarged view of a portion of FIG. 1 a.
FIG. 1 d is an enlarged view of a portion of FIG. 1 b.
FIG. 2 is a back view of the first embodiment of the invention.
FIG. 2 a is an enlarged view of the left side FIG. 2 .
FIG. 2 b is an enlarged view of the right side of FIG. 2 .
FIG. 2 c is an enlarged view of a portion of FIG. 2 a.
FIG. 2 d is an enlarged view of a portion of FIG. 2 b.
FIG. 3 is a top view of the first embodiment of the invention.
FIG. 3 a is an enlarged view of the right side of FIG. 3 .
FIG. 4 is a bottom view of the first embodiment of the invention.
FIG. 4 a is an enlarged view of the right side of FIG. 4 .
FIG. 5 is a detail view of the first embodiment of the invention being used to layout a common pitch setting for cutting common rafters.
FIG. 6 is a detail view of the first embodiment of the invention being used to layout a working stair setting for cutting a set of stair stringers.
FIG. 7 is a detail view of the first embodiment of the invention being used to layout a working hip pitch setting for hip rafters.
FIG. 8 is a detail view of the first embodiment of the invention being used as a working tee-square.
FIG. 9 is a front view of a second embodiment of the invention.
FIG. 9 a is an enlarged view of the left side of FIG. 9 .
FIG. 9 b is an enlarged view of the right side of FIG. 9 .
FIG. 9 c is an enlarged view of a portion of FIG. 9 a.
FIG. 9 d is an enlarged view of a portion of FIG. 9 b.
FIG. 10 is a back view of the second embodiment of the invention.
FIG. 10 a is an enlarged view of the left side of FIG. 10 .
FIG. 10 b is an enlarged view of the right side of FIG. 10 .
FIG. 10 c is an enlarged view of a portion of FIG. 10 a.
FIG. 10 d is an enlarged view of a portion of FIG. 10 b.
FIG. 11 is a top view of the second embodiment of the invention.
FIG. 11 a is an enlarged view of the left side of FIG. 11 .
FIG. 11 b is an enlarged view of the right side of FIG. 11 .
FIG. 12 is a bottom view of the second embodiment of the invention.
FIG. 12 a is an enlarged view of the right side of FIG. 12 .
FIG. 12 b is an enlarged view of a portion of the left side of FIG. 12 .
FIG. 13 is a detail view of the second embodiment of the invention being used to layout a common pitch setting for cutting common rafters.
FIG. 14 is a detail view of the second embodiment of the invention being used to layout a working stair setting for cutting a set of stair stringers.
FIG. 15 is a detail view of the second embodiment of the invention being used to layout a working hip pitch setting for hip rafters.
FIG. 16 is a detail view of the second embodiment of the invention being used as a working tee-square.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1 , 1 a , 1 b , 1 c and 1 d , a front view of the first embodiment of the invention is shown. This embodiment is designed to be used with standard framing squares. These squares, also known as steel squares have a short arm that is typically 16 inches long and a long arm, set at 90° to the short arm, that is typically 24 inches long. The front of the first embodiment consists of a panel 11 that has two slots 12 and 13 formed in it. In this embodiment, the slots 12 and 13 are 9 inches long and are 5/16 inches wide. A back panel 14 (see FIG. 2 ) is attached by fasteners 15 (see FIG. 3 a , or 4 a ) which can be considered as a means for attaching the front and back panels as well as a means for separating the two panels. The second panel has matching slots 12 a and 13 a in it such that when the two panels are connected, the slots align as shown. Knobs 16 are installed in the slots 12 , 12 a , 13 and 13 a , which allow the device to clamp down on a framing square that has been inserted in the device, as discussed below. The combination of the slots and knobs is considered as a means for temporarily locking the invention onto a framing square.
As shown, the front panel has a number of markings on it used for various purposes. FIG. 1 a is an enlarged view of the left side of FIG. 1 . FIG. 1 c is an enlarged view of a portion of FIG. 1 a . Here, markings 17 refer to common rafter roof pitches. Note that roof pitch is a measure of the steepness of a roof. It is typically expressed in ratios e.g., “3:12” or “5:12”). Pitch is expressed as rise over run. Thus, a “3:12” pitch means a 3-inch rise over a 12 inch run. Note also that common pitch is a 12 in run. The lines on the left of the device align with a framing square, as discussed below and indicate the rise of the pitch ranging from 1 to 14. These markings consist of 15 lines that begin with a vertical line that is placed at 12 inches from the pivot point 18 , discussed below.
The markings 17 consist of 16 lines placed at specific locations and angles. Below are the dimensions and the angles of the common pitch markings for the tool. These dimensions are measured from the 12″ pivot point:
TABLE 1
Placement of Common Rafter Lines
Roof Pitch
Distance from Pivot Point
Angle
1:12
12.042″
4.674 deg
2:12
12.166″
9.462 deg
3:12
12.369″
14.036 deg
4:12
12.649″
18.435 deg
5:12
13″
22.620 deg
6:12
13.416″
26.565 deg
7:12
13.892″
30.256 deg
8:12
14.422″
33.690 deg
9:12
15″
36.870 deg
10:12
15.621″
39.806 deg
11:12
16.279″
42.510 deg
12:12
16.971″
45 deg
13:12
17.692″
47.291 deg
14:12
18.439″
49.399 deg
15:12
19.209″
51.340 deg
16:12
20″
53.130 deg
FIG. 1 b is an enlarged view of the right side of FIG. 1 and FIG. 1 d is an enlarged view of a portion of FIG. 1 b.
This side has two important features. First, there is a 12-inch pivot point 18 . This is used with the pitch marks on the left of the tool to give the proper layout for common pitches, as discussed below. This pivot works for standard 16″×24″ framing squares or with smaller squares. As discussed below, the preferred embodiment is designed to work with any size square.
The right side of the front of the tool also has a number of lines that refer to angles ranging from 5 degrees to 45 degrees from the horizontal and from zero degrees to 45 degrees from the vertical. These lines act as a basic protractor 19 that is useful for scribing common angles, as described below.
FIG. 2 is a back view of the invention. Here, panel 14 is shown, with slots 12 a and 13 a and knobs 16 . This side too, has markings on both sides of the tool. FIG. 2 a is an enlarged view of the left side of FIG. 2 . FIG. 2 c is an enlarged view of a portion of FIG. 2 a . As before, the 12-inch pivot point 18 is again marked. Here also are lines 20 representing riser height. Note these lines are inverted as for measuring riser height the tool is positioned differently, as discussed below. Riser height here refers to stair riser (the vertical portion of a stair). Here, riser height ranges from 5 inches to 10 inches in ¼inch increments.
Below are the dimensions for the stair riser height lines 20 as measured from the 10″ Divot point:
TABLE 2
Stair Riser Line Placement
Riser Height
Distance From Pivot Point
Angle
5″
11.180″
26.565 deg
5.25″
11.294″
27.699 deg
5.5″
11.413
28.811 deg
5.75″
11.535″
29.899 deg
6″
11.662
30.964 deg
6.25″
11.792″
32.005 deg
6.5″
11.927″
33.024 deg
6.75″
12.065″
34.019 deg
7″
12.207″
34.992 deg
7.25″
12.352″
35.942 deg
7.5″
12.5″
36.870 deg
7.75″
12.652
37.776 deg
8″
12.806″
38.660 deg
8.25″
12.964
39.523 deg
8.5″
13.124″
40.365 deg
8.75″
13.288″
41.186 deg
9″
13.454″
41.987 deg
9.25″
13.622″
42.769 deg
9.5″
13.793″
43.531 deg
9.75″
13.966″
44.275 deg
10″
14.142″
45 deg
FIG. 2 b is an enlarged view of the right side of FIG. 2 . FIG. 2 d is an enlarged view of a portion of FIG. 2 b . Here, there is a marking for a 10-inch pivot point 21 , also inverted. This point is also used for stair measurements, as described below. On the bottom portion of the panel are marks 22 for measuring the angles for hip or valley type rafters. Here, the numbers range from 1 pitch to a 16 pitch. The technique for marking the rafters is discussed below.
The measurements for the marks 22 for the hip/val lines are as follows. Again, these lines are measured from the 12-inch pivot point:
TABLE 3
Placement of Hip/Val Lines
Roof Pitch
Distance from Pivot Point
Angle
1:12
12.021″
3.376 deg
2:12
12.083″
6.722 deg
3:12
12.186″
10.025 deg
4:12
12.329″
13.263 deg
5:12
12.510″
16.417 deg
6:12
12.728″
19.472 deg
7:12
12.981″
22.416 deg
8:12
13.267″
25.240 deg
9:12
13.583″
27.939 deg
10:12
13.929″
30.510 deg
11:12
14.300″
32.951 deg
12:12
14.697″
35.265 deg
13:12
15.116″
37.454 deg
14:12
15.557″
39.522 deg
15:12
16.016″
41.474 deg
16:12
16.493″
43.315 deg
17:12
16.986″
45.051 deg
18:12
17.493″
46.687 deg
FIG. 3 is a top view of the invention. As discussed above, panels 11 and 14 are connected by fasteners 15 (that are placed ½-inch from the end of the tool), which act as spacers that open a gap 15 a between the two panels. This gap allows a framing square to be inserted between, as discussed below. On this surface of the tool, a straight rule 23 is provided that can be used to mark the length of run for rafters as discussed below. Note that the zero mark 23 a corresponds to the 12-inch pivot point 18 on the faces of the panels. FIG. 3 a is an enlarged view of the right side of FIG. 3 . Here is ruler 23 is shown to be marked in one-inch segments on panel 14 and in ⅛-inch segments on panel 11 .
FIG. 4 is a bottom view of the invention. On this face, the tool has the tops of the riser height lines 20 on panel 14 brought down. On panel 11 , on the right side (see FIG. 4 a .) is a protractor 19 a showing angles ranging from zero degrees to 45 degrees. These are used as discussed below. Note too that the 12-inch pivot point 18 is shown. Note too, knobs 16 are shown as well.
FIG. 5 is a detail view of the first embodiment being used to layout a common pitch setting for cutting common rafters. Begin by installing a framing square 100 between the 2 panels of the tool as shown and aligning the 12″ pivot point 18 on the framing square at the 12-inch mark on the framing square. With the square now pivoting on the pivot point move the square up through the body of the tool until the body of the square lines up with the mark on the tool that denotes the desired roof pitch (here shown as point “X”. In the figure, a roof pitch of 8:12 is shown. When the square is in the desired position both set of knobs 16 are tightened causing friction that holds the framing square in place. With the tool held against the material a score along the body of the square using a scribe or pencil is made. In this way, multiple sets of rafters can quickly be marked and cut. Note that unlike the tools used in the prior art, no calculations are required to set the tool up. The user simply sets the pivot and moves the tool to the desired pitch line on the tool.
FIG. 6 is a detail view of the tool being used to layout a working stair setting for cutting stair stringers. Set the framing square to the corresponding 10″ pivot point 21 then set the square body to the desired riser height. Mark the layout with the parallel edge to your workpiece and scribe the stair stringer.
FIG. 7 is a detail view of the tool being used to layout a working hip pitch setting for hip rafters. Here, the back of the tool is used for this task. The square is set at the 12″ pivot point 18 just as when performing common rafter. Then, the body of the square is aligned with appropriate hip/val indicating line 22 (here, at point “Z”) and the procedure is completed as for common rafters.
FIG. 8 is a detail view of the tool being used as a working tee-square. With the tool 10 in a parallel position with the tongue or body of the framing square 100 , lock the tool in position with the knobs, which are tightened for this function. Once locked, the tool can be used with the square as a Tee-square for marking or for cutting sheetrock, for example. Locking the tool on the square in this position is also a good way to store the tool when it is not in use.
In addition to those functions described above, the tool can also be used for other functions. For example, to scribe angles. Here the tool is used in the same way as shown for cutting common rafters. The difference here is that the user references the degree increments located on the front (lines 19 on FIG. 1 b ) and or the degree markings found on the bottom side of the device (see protractor 19 a on FIG. 4 a ).
The device can also be used to measure length per foot of run. Here, the ruler 23 on the top of the device is used for this calculation. The square is set to the proper rise per foot as in the case of FIG. 8 and the 12″ mark on the square is set on the pivot point. When set, the dimension on the ruler 23 is multiplied by the number of feet in the required span to determine the appropriate rafter length.
Finally, the invention can be used to measure for level and angle cuts for truss fabrication and roof framing. Here the tool is set up as in FIG. 5 . The same procedure is used as in laying out a common rafter except the user marks the perpendicular end of the square 100 with the invention parallel with the building material for level roof and truss members that intersect with rafters.
As noted above, the use of the first embodiment is limited to framing squares of 16″×24″. The next embodiment is designed to work with framing squares of different sizes.
For FIGS. 9 , 9 a , 9 b , 9 c and 9 d a front view of the second embodiment of the invention 24 is shown. This embodiment is designed to be used with both standard and non-standard framing squares, making this embodiment a “universal” tool. For example with a larger square such as the “Chappell” square, which is 24×18. To that end, FIGS. 9 , 9 a , 9 b , 9 c and 9 d show the front of the second embodiment, which consists of a panel 25 that has two slots 26 and 27 formed in it. In this embodiment, the slots 26 and 27 and 13 are 11 inches long and are 5/16 inches wide. A second panel 28 (see FIG. 10 ) is attached by fastener/spacers 29 (see FIG. 11 , or 12 ). The second panel has matching slots 26 a and 27 a in it such that when the two panels are connected, the slots align as shown. Knobs 30 are installed in the slots 26 , 27 and 26 a and 27 a that allow the device to clamp down on a framing square that has been inserted in the device, as discussed below. The combination of the slots and knobs is considered as a means for temporarily locking the invention onto a framing square.
As shown, the front panel of the second embodiment has a number of markings on it used for various purposes. FIG. 9 a is an enlarged view of the left side of FIG. 9 . FIG. 9 c is an enlarged view of a portion of FIG. 9 a . Here, the markings are a number of lines that refer to angles ranging from 5 degrees to 90 degrees. These lines act as a basic protractor 31 that is useful for scribing common angles, as described below. Note too that there is a first pivot point 32 at the bottom of the front panel as shown. This pivot point is two inches from the left edge.
The right side of the front panel ( FIG. 9 b ) has markings 33 for common rafter roof pitches similar to those of the first embodiment. FIG. 9 d is an enlarged view of a portion of FIG. 9 b . Note, however, that the lines are a different position as compared to those in the first embodiment. Note also that on this side, there is no 12-inch pivot point on this side of the invention (as compared to the first embodiment).
FIG. 10 is a back view of the second embodiment of the invention. Here, panel 28 is shown, with slots 26 a and 27 a and knobs 30 . This side too, has markings on both sides of the tool. FIG. 10 a is an enlarged view of the left side of FIG. 10 . FIG. 10 c is an enlarged view of a portion of FIG. 10 a . Here, a 10-inch inch pivot point 34 is marked at the top of the tool. Here also are lines 35 for measuring the angles for hip or valley type rafters. Here, the numbers range from 1 pitch to an 18 pitch. Note that the numbers for the lines are located at the bottom of the device. FIG. 10 b is an enlarged view of the right side of the back of the tool. FIG. 10 d is an enlarged view of a portion of FIG. 10 b . On this side, are marks 36 for riser height. Note these lines are inverted as for measuring riser height the tool is positioned differently, as discussed below. Riser height here refers to stair riser (the vertical portion of a stair). Here, riser height ranges from 5 inches to 10 inches in ¼inch increments. Note that these lines have been relocated and modified for the second embodiment. Note too, the pivot 32 from the front of the tool, is marked at the bottom of the back, as shown.
FIG. 11 is a top view of the second embodiment of the invention. Here, the front panel 25 and the rear panel 28 are shown. Note too are the fastener/spacers 29 . On this face, the tool has the tops of the riser height lines 33 on panel 28 brought up. Note too that the 10-inch pivot point 34 is shown. Knobs 30 are shown as well. FIG. 11 a is an enlarged view of the left side of FIG. 11 . Here the tops of the lines 33 are shown as noted. FIG. 11 is an enlarged view of the right side of FIG. 14 . Here a detail of the pivot point 34 , which is still 12 inches on the square, is shown.
FIG. 12 is a bottom view of the second embodiment of the invention. As discussed above, panels 26 and 28 are connected by fasteners 29 , which act as spacers that open a gap 29 a between the two panels. This gap allows a framing square to be inserted between, as discussed below. On this surface of the tool, a straight rule 40 is provided that can be used to mark the length of run as discussed below. Note that the zero mark 41 corresponds to the pivot point 32 on the faces of the panels. FIG. 12 a is an enlarged view of the right side of FIG. 12 . The ruler is shown to be marked in one-inch segments on panel 26 . FIG. 12 b is an enlarged view of a portion of the left side of FIG. 12 . Here, the rule 40 is shown as well as the bottoms of the hip/val lines 35 on the face 28 .
FIG. 13 is a detail view of the second embodiment of the invention being used to layout a common pitch setting for cutting common rafters. The procedure is basically the same as that for the first embodiment. The major difference is the change on the pivot point. By placing the pivot point as shown, it is possible to use the tool with longer length squares. To use this embodiment, begin by installing a framing square 100 between the 2 panels of the tool as shown and aligning the pivot point 32 on the framing square at the 12-inch mark. With the square now pivoting on the pivot point move the square up through the body of the tool until the body of the square lines up with the mark on the tool that denotes the desired roof pitch. In the figure, a roof pitch of 6:12 is shown. When the square is in the desired position both set of knobs 16 are tightened causing friction that holds the framing square in place. With the tool held against the material a score along the body or tongue of the square using a scribe or pencil is made. In this way, multiple sets of rafters can quickly be marked and cut. Note that unlike the tools used in the prior art, no calculations are required to set the tool up. The user simply sets the pivot and moves the tool to the desired pitch line on the tool.
FIG. 14 is a detail view of the second embodiment of the invention 24 being used to layout a working stair setting for cutting a set of stair stringers. To use this embodiment, set the framing square 100 to the 10-inch pivot point 34 as shown. Then set the square body to the desired riser height 36 . Lock the tool to the framing square and mark the layout with the parallel edge to your workpiece and scribe the stair stringer.
FIG. 15 is a detail view of the second embodiment of the invention 24 being used to layout a working hip pitch setting for hip rafters. Here, the back of the tool is used for this task. The square is set at the pivot point 32 just as when performing common rafter. Then, the body of the square is aligned with appropriate hip/val indicating line 35 . The tool is locked into place and the procedure is completed as for common rafters.
FIG. 16 is a detail view of the second embodiment of the invention being used as a working tee-square. With the tool 24 in a parallel position with the tongue or body of the framing square 100 , lock the tool in position with the knobs, which are tightened for this function. Once locked, the tool can be used with the square as a Tee-square for marking or for cutting sheetrock, for example. Locking the tool on the square in this position is also a good way to store the tool when it is not in use. Note too, that it is possible to keep the edge of the square protruding from the tool when the tool is in the Tee square position to help stabilize the square and tool.
In addition, the device can be used to measure length per foot of run. Here, the ruler 40 on the bottom of the device is used for this calculation. The square 100 is set to the proper rise per foot as in the case of FIG. 13 and the proper mark on the square is set on the pivot point 32 on the tool 24 . When set, the outermost dimension 40 a on the ruler 40 is taken from the square 100 and multiplied by the number of feet in the required span to determine the appropriate rafter length. Thus for example, with a measurement of 22 inches for a 20-foot span results in a rafter length of 440 inches or 36.7 feet. Either the second embodiment or the first embodiment can be used for this measurement. Of course, the tool will be set up in accordance with that particular tool's markings.
The present disclosure should not be construed in any limited sense other than that limited by the scope of the claims having regard to the teachings herein and the prior art being apparent with the preferred form of the invention disclosed herein and which reveals details of structure of a preferred form necessary for a better understanding of the invention and may be subject to change by skilled persons within the scope of the invention without departing from the concept thereof. | An attachment tool for framing squares. The tool is made of a pair of straight members that are fastened together with a space therebetween. Each of the members has a pair of horizontal grooves that are aligned. A fasteners is positioned within each of the grooves to lock a framing square in place once the desired setting have been determined. The tool has markings on each face that are used to establish angles for desired cuts. Using pivot points that are placed on the tool, the framing square can be set at one point and the pivoted to the desired angle using the markings on the tool without having to calculate anything. In this way, many different types of building members including: rafters, trusses and stairs can be laid out, marked and cut with minimal error and optimal efficiency. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to single or multilayer smart susceptors used for achieving thermal uniformity in induction processing of organic matrix composites or metals. The improved smart susceptor has a coating to minimize oxidation during repeated use in induction process manufacturing.
An induction processing system used for fabrication of material combines, metals and the like are disclosed in U.S. Pat. Ser. Nos. 5,808,281, 5,728,309, and 5,645,744 and is hereby incorporated by reference. The induction processing system uses susceptors to translate electrical energy to heat energy for fabrication of various parts and structures. The susceptors are often referred to as smart susceptors because the material composition is specifically chosen to produce a set temperature point when used in an induction processing system.
The sheets of material used to construct the susceptor may consist of ferromagnetic materials including a combination of iron (Fe), nickel (Ni), and/or cobalt (Co). For the higher temperature applications the alloys may be Co based with additions of Fe and Ni. Each specific composition and combination of material sheets constructed is based on the Curie temperature characteristics desired of the susceptor. The Curie Point at which there is a transition between the ferromagnetic and paramagnetic phases of a material is used to set the equilibrium temperature point caused by inductive heating in the inductive processing system.
The use of smart susceptor alloys such as combinations of Co, Ni and Fe material in cycling to elevated temperatures in inductive processing systems may cause oxidation of the susceptor material. It has been found that at elevated temperatures these alloys may oxidize at a relatively aggressive rate. In addition, the iron oxide formed may create a low melting point intermetallic interface when positioned in close proximity to the die material at elevated temperature. These conditions may cause the susceptors to deteriorate prematurely requiring replacement thereof. Also, the susceptors may interact with the die material, a ceramic, which necessitates die repair or replacement.
The known approach to reducing the effects of the oxidation of the susceptor has been to insert an intermediate metal sheet of material, such as Inconel 625™, between the susceptor and the die. Material such as Inconel 625™ is a nickel base alloy that is non-magnetic and has oxidation resistive qualities. While this solves the interaction problem, it does not eliminate the oxidation problem and adds additional parts to the system tooling requirements.
One solution to oxidation of the metal surface is the coating thereof. Examples include coating of steel and other materials in internal combustion engines where the high temperature combined with exposure to air create an environment that may be corrosive and cause erosion of metal surfaces. A method of flame or plasma spraying a thin coating layer on the exposed metal surfaces has been used to reduce oxidation damage. Various materials have been used to coat metals and other materials depending on the application. U.S. Pat. No. 3,762,884 discloses one such process as well as surveying other methods. These coatings were not applied to environments such as those for which the present invention is intended nor have coating compositions been formulated to solve the smart susceptor problem.
The coated smart susceptor and method therefore improves the control of superplastic forming, hot forming and/or heat treating processes to achieve a higher quality fabricated part. The coated susceptor use also enables cold loading and unloading of parts that improves dimensional control. The quick thermal cycles with induction processing and the improved life of the susceptor due to the coating reduces the need for batch loading of material as such is no longer required for economic viability of the fabrication processes.
As can be seen, there is a need for a simple, effective protectant to minimize oxidation of susceptors used in induction processing systems.
SUMMARY OF THE INVENTION
An improved susceptor construction and method according to the present invention comprises a metal alloy composition susceptor having a nickel aluminide (NiAl) coating thereon.
In one aspect of the present invention, a susceptor for temperature control of a part fabrication in an induction processing system comprises a single layer or a lamination of layers of ferromagnetic material susceptible to heating by induction, each having a selected Curie point. The single layer or laminated material layers are then coated with a nickel aluminide surface coat for oxidation protection during temperature cycling for part fabrication in the induction processing system. Also, the temperature at which the nickel aluminide may be sprayed to coat a susceptor and any exothermic reaction from the process generates heat creating a sintering effect to bond the coating to the susceptor outer surface.
In another aspect of the invention, the multiplayer susceptor may include an Al 2 O 3 adherent layer formed on the surface coating to inhibit deterioration of the surface coating. The nickel aluminide coating may create it's own Al 2 O 3 layer at the surface. This oxide film and the very stable thermally resistant nickel aluminide layer underneath may form an oxidation barrier.
A further aspect of the present invention involves the method for producing a single or multilayer susceptor having a surface coat oxidation protective layer comprising the steps of fabricating a single layer or a plurality of laminated material layers of ferromagnetic material, introducing a wire or powder mixture of nickel and aluminum into a flame or plasma spray gun, operating the spray gun to heat the powder or wire to form droplets and to spray the droplets on an outer surface of the single or laminated material layers, and continuing the spraying to sinter a surface coating of nickel aluminide to the outer surface.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a schematic representation of an induction processing system according to the prior art;
FIG. 2 illustrates a partial cross-sectional view of the tooling with smart susceptor according to the prior art;
FIG. 3 illustrates a partial perspective view of an induction processing tool with temperature gradients according to the prior art;
FIG. 4 illustrates a transition diagram of the deposition of nickel aluminide coating of a susceptor according to the present invention;
FIG. 5 illustrates a cross-sectional view of an aluminum nickel formed wire for use in a plasma spray gun according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
Referring to FIG. 1, an induction processing system 10 has metal support plates 12 mounted on support posts 14 that may be used to constrain a tool 20 such as a phenolic box under pressure. The tool 20 includes ceramic die halves 22 which contain the part cavity 24 therebetween. A susceptor (not shown) is mounted in a cavity 24 .
The tool 20 includes reinforcing rods 26 for reinforcement of the ceramic dies 22 . The tool 20 also incorporates induction coils 28 for heating and coolant conduits 30 for temperature control. Flexible coil connections 32 are provided external to the dies 22 to connect induction coils 28 and coolant conduits 30 . In operation, electric power is applied to the induction coils 28 that due to magnetic induction heat the susceptor contained in the part cavity 24 .
Referring to FIG. 2, a portion of the tool 20 with ceramic dies 22 and reinforcing rods 26 includes part cavity 24 . A susceptor 40 with a fabrication part 42 may be contained therein. For a particular part 42 manufacture for super-plastic forming thereof a relative temperature in the part cavity 24 at the ceramic die 22 inner surface may be 1,650° F. A single layer susceptor 40 may be used when there is just one crucial processing temperature necessary for part fabrication. The susceptor 40 may be coated on all external surfaces.
Referring to FIG. 3, the ceramic die 22 has electric power applied at induction coil 28 . A temperature of 1,650° F. may be desired at the inner surface 36 of the ceramic die 22 in the part cavity 24 for interior point 33 heating of the susceptor (not shown). With the ceramic die 22 characteristics the temperature between the induction coil 28 and the inner surface 36 may be 333° F. at an intermediate point 38 . A susceptor may be maintained at the desired Curie Point when sufficient electric power is applied to the induction coils 28 and proper cooling is flowing through coolant conduits 30 . The environment point 34 may be room or ambient temperature.
In use, the induction processing system 10 may have material placed in it for heat treatment, forming, consolidation, etc. The system may then be closed and activated to raise and maintain the internal part cavity 24 at the desired temperature. The system may then be cooled and the part removed. This is a cycle process that is repeated for the production of each part.
Referring to FIG. 4, the susceptor 40 may consist of a single or lamination of sheets of highly ferromagnetic materials composed of a combination of Fe, Ni, and/or Co. In higher relative temperature applications the alloys may be Co based with additions of Fe and Ni. The higher the Fe content the more likely the susceptor 40 maintains a set temperature, that is, the smarter it appears.
The Fe and the elevated temperature may combine to form flakes of iron oxide on the susceptor 40 outer surface 44 as a result of the temperature cycling process. It has been found by experiment that coating the susceptor 40 with a nickel aluminide plasma spray coat 50 inhibits oxide formation. The approximate effective coating thickness may be about 0.005 inch to 0.010 inch.
To apply the coating 50 , a wire 56 consisting of a nickel powder 60 enclosed in an aluminum foil 58 as illustrated in FIG. 5 may be used in a flame or plasma spray gun. The composition of the wire 56 may be nickel powder of approximately −125 to +45 um (−120 to +325 mesh) range of granularity and represent approximately 79.5 to 80.5 percent of a unit cross section of the wire 56 by weight. The aluminum foil 58 may be approximately 0.010 to 0.015 inch thickness and approximately 19.5 to 20.5 percent of a unit cross section of the wire 56 by weight. A wire 56 that may be ⅛ inch in diameter may define a foil thickness to achieve an approximately 20 percent aluminum content wherein the foil thickness may be related to the diameter and powder density. The use of the flame or plasma spray gun as understood in the art melts the wire 56 and the resulting liquid may be sprayed on the susceptor 40 using a compressed gas.
A powder mixture of nickel and aluminum may also be used for spraying with a flame or plasma spray gun. The powder mixture may also have an approximate ratio of 80 percent nickel and 20 percent aluminum.
During the melting and spraying action the nickel and aluminum are mixed together and begin to react as droplets 54 . This may be an exothermic reaction and therefore heat may be generated. When the droplets 54 contact the susceptor 40 they may still be reacting and therefore tend to sinter to the outer surface 44 interface 52 due to the heat created. This combination of actions may result in a strong bond of converted nickel aluminide on the susceptor 40 .
It has been found that the nickel aluminde intermetallic is chemically very stable as evidenced by the exothermic reaction occurring during the spray coating. The nickel aluminide coating may form a stable adherent Al 2 O 3 surface layer 62 when used at the processing temperatures for the susceptor 40 . It has been found that after approximately two cycles of use of a coated susceptor 40 in manufacturing that an approximate 0.0002 inch to 0.0008 inch (5 to 20 microns) thick coating of Al 2 O 3 is formed on the nickel aluminide coating. If the Al 2 O 3 layer cracks during use, the ductile nickel aluminide coating can reform the oxide layer at elevated temperatures. The result may be a stable and strong oxidation resistant coating on the susceptor 40 .
It should be understood, of course, that the foregoing relates to preferred embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. | A single or multilayer smart susceptor for temperature control of part fabrication in an induction processing system generally consists of single layer or laminated layers of ferromagnetic material susceptible to heating by induction. The use of the susceptors in fabrication at elevated temperatures causes oxidation damage to the surface. The susceptor may be coated with a nickel aluminide surface coating to minimize oxidation of the susceptor outer surface. | 7 |
BACKGROUND OF THE INVENTION
Vehicles, such as cars, are almost a necessity in our civilization, and their care and maintenance becomes equally vital to the civilization. Many of the services required for the maintenance of a car are routine, and functions, such as draining the crankcase of a car have been fairly well organized in most service stations. Crankcase draining is usually accomplished by the use a funnel-like receiver, positioned under a crankcase drain tap, for draining oil and residue into a storage container of any type.
Other functions such as the servicing of an automatic transmission, (where drainage plugs may not be provided), are more troublesome since they may require the removal of a bulky oil pan with the potential spillage of the oils or greases in the pan. This becomes a messy and unpleasant chore that may require two mechanics, and is usually overlooked by maintenance men. The standard funnels for collecting crankcase oils are too small to be of use here, and are otherwise inadequate.
It is therefore an object of this invention to provide the combination of a work holder to support a portion of a car, such as the oil pan of an automatic transmission -- while it is being loosened or removed from a car -- and a catch pan substantially larger than the oil pan to catch any spillage from the oil pan during the process.
SUMMARY OF THE INVENTION
A catch pan is provided that is substantially larger than the oil pan of an automatic transmission or the portion of a car that is being serviced. This catch pan is supported by a central, hollow mounting tube or drainpipe that can fit into the tubular receiving tube of a storage container that may be of conventional size and shape. The storage container may be supported on casters in a well known manner to be free to be moved or positioned under a car being serviced.
A work holder is provided to be supported and held securely by the catch pan. The work holder must extend far enough above the catch pan to allow access to the portion of the under body of the car that is supported by the work holder.
The central, hollow mounting tube that supports the catch pan is free to move up and down in the tubular receiving tube of the storage container to adjust the work holder to the height of the portion of the underbody that is being serviced. At this height the tubes are secured by a lock screw, or the like, to hold the assembly until the operation is completed.
The device is readily moved into position under a car being serviced, and readily adjusted to the precise height for servicing any particular portion of the car. It must be strong enough to support the portion of the car while it is being serviced, and its catch pan must be large enough to catch any and all residue from this portion of the car while it is being serviced. The residue may drain into the storage container for later disposal, or it may be retained in the catch pan for observation or reuse. The entire operation can be handled by a single mechanic, with a minimum of time on the job and a minimum of clean-up time.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross section of the subject device in operation;
FIG. 2 shows a view of the work holder and catch pan from above; and
FIG. 3 shows an enlarged cross section of the mounting of the catch pan.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 shows a cross section of the device supported in a typical manner. A catch pan 10 has a bottom portion 11 and edge portions 12 that have recesses 13 for receiving the braces of a work holder 20. The catch pan may have a central indentation or depression 14 in the bottom portion, with a central drain hole through which a drain fitting 15 can be attached to a mounting tube 33, by means of screw threads 17, to secure and support the whole device. This is seen more clearly in FIG. 3. The drain fitting includes a strainer 16, and may have a removeable plug 18.
The work holder 20 comprises cross arms or braces 21 and 22 whose extremities engage the recesses 13 in the catch pan. The cross braces have flattened central portions 23 and 24, respectively, for supporting a typical portion of the underbody of a car, such as an automatic transmission oil pan 26, which is secured to the rest of the transmission by bolts 28.
A storage container 30 has a vertical receiving tube 31 with a lock screw 32 for securing the mounting tube 33 whose upper end is coupled to the catch pan. This coupling includes a flange or washer 34 where it engages and supports the catch pan. The storage container may also have a handle 37 and a pouring spout 38. Wheels or castors 41 and 42 may provide mobility in a well known manner.
FIG. 2 shows a plan view looking down on the work holder and catch pan, and has the same reference numbers for the same elements that are already described in the other figures.
FIG. 3 shows an enlarged cross section of the coupling between the bottom portion 11 of the catch pan and the mounting tube 33. This figure also shows, more clearly, typical screw threads 17 between the drain fitting 15 and the mounting tube 33 that may be used to secure the catch pan to the mounting tube.
In the typical coupling between the catch pan and the mounting tube shown here, the flanged, threaded drain fitting screws into the mounting tube, which may have a metal washer or flange 34 to provide better support for the catch pan and work holder. Gaskets, of well known types, now shown, may be included between the flange of the drain fitting, or the washer, and the bottom of the catch pan to avoid leakage.
In operation, the complete assembly, as seen in FIG. 1, is wheeled under a car or the like, until the work holder 20 is directly under a portion of the car to be serviced. The lock screw 32 is then released and the upper mounting tube 33 is raised until the flattened central portions 23 and 24 of the work holder engage the desired portion of the car. At this point, the lock screw is tightened to hold the assembly in position.
If it is desired to work on, or to provide routine maintenance on, an automatic transmission, for example, the mounting bolts 28 can then be unloosened by a single mechanic to release the transmission oil pan 26. Any excess oil or grease from the transmission will fall into the catch pan with a minimum of mess for the mechanic or the floor of the garage. The mounting tube may be lowered for working on the transmission, or the oil in the transmission pan may be dumped into the catch pan, or the whole assembly may be moved away at the convenience of the mechanic.
It should be noted that this whole operation can be handled by one mechanic, whereas without this device, it would take two mechanics, one to support the transmission oil pan and the other to loosen the bolts, to perform the same operation. It should also be noted that there would be extra time lost in the cleaning up of the floor of the garage with the inevitable spillage after any such operation.
There is a real need for this device for working on automatic transmissions and the like, but its use is not limited to such operations. The large collecting area of the catch pan and the access space above it would make this device useful for servicing brake drums, differentials, or radiators, etc., where there may be a substantial spillage of liquids, or risk of losing small parts.
The work holder, accordingly, may be removeable and is not limited to the typical shape or structure shown in FIGS. 1 and 2. It may be formed to accommodate the configuration of any special oil pan or other structure under a car. The work holder must extend far enough above the catch pan to permit access for whatever must be done, however, if the work holder is too high, there will be other disadvantages and problems. If necessary, a variable-height work holder can be provided.
This work holder is shown clipped into the catch pan, and can easily be snapped out for cleaning or replacement with another unit of the same or another shape. Other means, both separable and inseparable, for coupling the work holder to the catch pan, will suggest themselves to anyone skilled in the art. Clamps may be used to make a more rigid contact between the catch pan and the work holder, or they may be bolted together. The main factor in the combination of work holder and catch pan is that no part of the work holder projects beyond the edges of the pan so that all oil spillage will, ultimately, drain into the pan.
The typical catch pan shown in FIG. 2 is square, for convenience in manufacture; in this case by cutting, folding, and welding a piece of sheet metal. However, the pan could be almost any shape and could be stamped, or molded, or made in any well known manner. As noted earlier, the pan must be large enough to extend beyond the edges of the portion of the car being worked on, and must be strong enough to support the work holder, as well as the portion of the car being worked on, and any liquids in the pan.
The mounting tube 33 should be of a standard size to fit into the vertical receiving tube of a standard container. This will normally be strong enough to support the catch pan and the work holder when suitably secured by the drain fitting. However, in special circumstances, additional reenforcements may be necessary. If the mounting pipe and the bottom of the catch pan are not strong enough to support a large and heavy unit, additional braces can be added in a well known manner, to support any portion of the overall device.
The storage container may be one of the available types for use with a small funnel-like structure for catching crankcase oil. Some of the receiving tubes of these containers are of a standard, fairly-large size, and could be adapted to receive the mounting tube 33 without any modifications, except, possibly, a stronger lock screw 32. The base, including the wheels 41 and 42, must, of course, be wide enough and strong enough to accommodate the higher and heavier structure of the subject device.
If the lock screw 32 does not appear to be strong enough to support this device, additional or heavier lock screws may be provided. In addition, levering or jacking devices of well-known types may also be adapted to the moveable coupling between the receiving tube and the mounting tube to provide better support, or more easily and precisely controllable motion between the two.
The plug 18 would be convenient for containing any liquids that spill into the catch pan, in the event that they may be reuseable, or that they should be studied to observe color, consistency, or any other significant characteristic or contents. Similarly, the strainer 16 is desirable for catching nuts and bolts or small tools, etc., that may have fallen into the catch pan during the operation.
It is to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art. | A work holder mounted on a catch pan or drain provides a flat grid to support an oil or grease carrying portion of a vehicle or the like. The flat grid is supported by and positioned centrally above the catch pan, which is substantially larger than the oil carrying portion of the vehicle. The catch pan is supported by a hollow central mounting tube through which any liquids collected in the pan may drain into a storage container for disposal in a routine manner. The storage container may support the mounting tube. | 1 |
FIELD OF THE INVENTION
The invention relates to supplying information that has a relationship with content information being received by an end-user's consumer electronics (CE) apparatus.
BACKGROUND ART
The term “Interactive TV” (ITV) refers to enhancing TV programs with interactive services for the end-user. These services include, e.g., retrieving electronic information from, or sending electronic information to, specific Web sites via a dedicated set-top box (STB) within a context of the live-broadcast program. Examples of ITV are games for a TV audience, or interacting with an advertisement being broadcast. For example, Wink Communications provides an end-to-end system for low-cost electronic commerce on television. Their enhanced broadcasting system allows advertisers and others to create interactive enhancements to traditional TV programs. Viewers can purchase products or order brochures with a click of their remote control communicating with a STB or TV set that has the Wink client software built-in, during an enhanced program. OpenTV, Inc., provides software for STBs that enables digital interactive television for enhanced applications such as e-commerce.
SUMMARY OF THE INVENTION
ITV typically requires a dedicated infrastructure according to the specifications of the service provider, equipment manufacturer and network operator or cable provider. The inventor has realized that it is an advantage if the end-user or consumer receives the additional information related to a TV program, or a radio program, etc., without modifications being necessary to the conventional infrastructure used for supply of those programs to the end-user, including to the end-user device for receiving these programs, i.e. radios, TV sets and STBs. The inventor has also realized that the device receiving that additional information is preferably an item that is native to the home entertainment environment.
For these and other reasons, the inventor proposes to equip a remote control device (RC) with a communication apparatus such as a wireless telephone or pager, to receive the additional information from a server via a telephone network. The telephone or pager is preferably a built-in component. The RC has a display monitor that serves as a GUI. The monitor preferably has a touch screen functionality such as on the Pronto (TM) RC of Philips Electronics. The broadcast of the program causes the additional information to be sent to the RC. The additional information is displayed as, e.g., text or icons, on the GUI. User-interaction with the text or icons causes output data to be sent back via the telephone network to the server mentioned above or to another server.
Applications may need to be able to cope with the characteristic delays of the networks. Various services can be introduced on cell phones that rely on real-time or semi-real-time delivery of various data. E.g., subscribers can program a stock order system to provide an SMS alert when a stock price passes a certain value. Moreover, for accurate synchronization, watermarks can be embedded in the program. These allow, for example, that all the data required to respond to a certain event in the broadcast is already available on the RC but its rendering is triggered after the associated watermark is detected in the actual broadcast. Another method is to send data in advance and to put a time-stamp on it for its validity. Advantages are manifold. For example, interactive TV is enabled in a manner that is independent of a configuration of an STB, as the invention uses the telephone as communication medium. Further, the RC/telephone combination is independent of the STB's or TV's content delivery infrastructure (cable, satellite, etc.). TV shows or broadcast stations can fund a dedicated remote (e.g., distinguishable by the color of the housing, the ccf files controlling the GUI, the shape of the housing, etc.). The RC supports business models wherein TV shows, TV networks and stations and original content providers are revenue sources for the RC platform.
One way of implementing the synchronization between TV program and data delivery to the RC is to do everything in real-time. The current, so-called two-screen Interactive TV (watching TV while browsing the Web on a PC) uses a similar synchronization. Disney does this for “Millionaire” and MTV 2 does it with most of their programs as well.
Another way is to send messages to the phone or pager at the time that an EPG schedule indicates that a certain program is being broadcast. The phone does not need to have access to this schedule. A separate, central system interprets the EPG and triggers the relevant phones. This system needs to be aware of the differences in time in the different zones and it needs to be aware which RC-phones are present in which zones. A registration procedure may take care of this. Alternatively, cell-phone technology does have the possibility to track the geographical location of the device, e.g., through satellite based (e.g., GPS) or radio triangulation (e.g., MPS). Still another way of synchronizing is having the RC recognize the TV program. This implementation is robust against program shifts, both accidental and intended. Enabling technologies include, e.g., watermarks (embedded in the audio and/or video) and fingerprints (used to recognize the audio and/or video). The RC-phone detects the watermark, or calculates the fingerprint, calls the server, and requests instructions that match the watermark data or the fingerprint. For fingerprints in content information see, e.g., U.S. Pat. No. 5,668,603, herein incorporated by reference. Synchronizing with the playback of previously recorded content information is possible by the same mechanisms of watermarking and fingerprinting.
An aspect of the invention resides in a method of enabling a consumer to receive data under control of content information being played out at home equipment of the consumer. The content information has been supplied via a supply infrastructure, e.g., cable, satellite, etc. The method comprises supplying the data via a data network that is independent of the supply infrastructure. The data is supplied to a bi-directional telecom apparatus at the consumer, e.g., prior to the play-out of the content information or functionally simultaneously with the content being played out. The data is rendered upon the apparatus receiving a control signal caused by the content information being played out, either as streamed or received, or as played out from a recording apparatus. In an embodiment, the data is supplied by a server and is personalized according to a user profile based on an identity of the telecom apparatus. For example, the data represent instant buy buttons for products that relate to the semantic context of a TV broadcast. The buttons can be rendered on the display of the touch screen of the remote control device. In an example, the data for the buttons has been downloaded from the server on the remote for selectively being rendered upon detection of an associated watermark in the content being played out. The server downloads data for only specific ones of these buy buttons to this remote control as match the user profile. Alternatively, if all buttons have been downloaded, only specific ones are rendered under control of the watermark, as fit this user's profile. This selective rendering is achieved by, e.g., marking the data for each button as matching or conflicting.
For completeness, U.S. Pat. Nos. 5,414,761 and 5,748,716, both herein incorporated by reference, disclose an RC receiving control codes via a telephone line for being programmed into the remote's memory in the configuration phase of the remote. The remote does not have an onboard telephone or another telecom apparatus for enabling a user interactive broadcast based on operational use of the remote using typically bi-directional communication with a server within an Interactive TV context.
BRIEF DESCRIPTION OF THE EMBODIMENTS
The invention is explained in further detail below, by way of example, and with reference to the accompanying drawing, wherein FIG. 1 is a block diagram of a system in the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
As briefly discussed above, the invention relates to a remote control device (RC) for control of home entertainment equipment. The device comprises a telephone or another telecommunication apparatus for data communication. Other mechanisms can be used that allow the RC to communicate independently of the TV infrastructure. E.g., a modem and telephone line, wireless IP connection, two-way pager, etc. The device preferably comprises a GUI with a display monitor, e.g., one that has a touch screen functionality. The data received by the telephone are rendered on the display monitor. User-interaction with the rendered data is enabled through the touch screen or RC buttons.
Preferably, the data communication or data rendering is synchronized or otherwise put into a proper temporal relationship with the TV program or radio program being broadcast or being played back after having been recorded locally at the user's equipment. Therefore, the RC device comprises a detector for detecting a control signal in the content information being played out. The control signal serves to trigger the appropriate behavior of the RC device. The control signal is, e.g., embedded in the content information as an audio watermark. The detector is then operative to detect this audio watermark. As another example, the control signal is embedded as a video watermark. The device then cooperates with a detector (e.g., accommodated in the device or accommodated in another apparatus and communicating with the RC device through a short range coupling, e.g., Bluetooth) for detecting the video watermarking signal. Note that watermarking of the content information enables to render the data communication independent of time-shifting of the content's playback through recording.
An aspect of the invention resides in having content information for being broadcast comprising a control signal for control of data communication via a telephone. This enables synchronizing the communication with the content information being played out, e.g., as a live broadcast or time-shifted through a recording at a digital recorder.
FIG. 1 is a block diagram of a system 100 in the invention. System 100 comprises a TV broadcast station 102 and a TV receiver 104 of a consumer receiving a program broadcast by station 102 . The program has associated with it an interactive service that enables communication between the end-user and a server 106 via a data network 108 . The end-user has available a remote control device 110 . Device 110 allows the user to control his/her home equipment through IR or RF. Device 110 preferably has a display monitor 112 with touch screen functionality. Device 110 comprises, e.g., a Pronto (™) universal programmable remote control device as manufactured by Philips Electronics. In the control mode of device 110 , monitor 112 presents icons with which the user interacts through the touch screen. Interaction with an icon causes device 110 to send a specific IR or RF control command to the associated CE equipment, e.g., receiver 104 or a digital video recorder 114 , or another CE apparatus. Device 110 accommodates a telecommunications device 116 , e.g., a cell phone or a pager, to enable data communication with server 106 via network 108 . In a data communication mode of device 110 , the data communicated from server 106 is processed by processor 118 and rendered on screen 112 , e.g., as text and/or icons and/or another graphics representation. Selection of an item rendered is accomplished through user-interaction with touch screen 112 . The user-interaction causes data to be sent back to server 106 . Device 110 has an audio watermark receiver 120 . Receiver 120 detects a specific audio watermark embedded in the audio part of the content played out (live or from recorder 114 ) at TV receiver 104 . The watermark is used to control the data communication with server 106 . For example, during the play-out of a specific part of content information, receiver 120 detects a specific watermark The watermark detected is processed by processor 118 that extracts a request to retrieve certain information from server 106 . The request may be as little as a pointer to a specific piece of information, depending on the program broadcast. For example, processor 118 has received a look-up-table from server 106 that translates the watermark into a pointer. The request is sent via phone 116 to server 106 . The latter thereupon sends the information to phone 116 that passes it on to processor 118 . The information is processed and rendered on screen 112 under control of processor 118 . In this manner, the information supply via network 108 and the play-out of the content are synchronized under control of the watermark embedded in the content. A video watermark 122 can be used in addition to, or instead of, audio watermark detector 120 , but may be less practical when accommodated in remote 110 because of the line of sight needed between the display of TV receiver 104 and detector 122 . Video watermark detector 122 is built-in or added to TV receiver 104 and communicates with remote 110 using a short range RF communication protocol, e.g., Bluetooth. Processor 118 then controls communication device 116 in a manner similar to the one discussed above with respect to the audio watermark.
In an embodiment of the invention, telephone 110 has been registered as owned by this specific user. Together with the request extracted from the watermark, phone 116 sends a unique identifier to server 106 . Accordingly, server 106 can distinguish between different users and can adapt the supply of information accordingly.
In a further embodiment of the invention, the information supplied by server 106 comprises advertisements for goods or services that fit in with the semantic context of the content information being played out. For example, a specific scene of a movie being played out via the user's equipment takes place in a certain geographic environment. This scene comprises a watermark. Detection of the watermark causes telephone 116 to contact server 106 , that in turn sends an advertisement for a vacation in that environment. The advertisement is displayed on the RC's screen. An interested user can, e.g., respond to request additional information by mail, or save the text for studying it later in more detail. As another example, the information supplied by server 106 concerns information on merchandise that can be related to the broadcast. Processor 118 and the GUI on Screen 112 provide the option to buy it directly by sending the user's response to Server 106 . As still another example, assume that the content played out is a live broadcast. The information supplied by server 106 contains background information about the events being broadcast. This information may have been prepared in advance or has been compiled in real-time by an editor at the studio. The watermark now is being used as a synchronizing mechanism.
Note that the relationship between a watermark and the information caused to be supplied by server 106 when the mark is detected, is preferably modifiable, dynamic or personalized. For example, server 106 may keep a log of what has been supplied to this specific user on previous occasions. In this manner, the information can be different each time the user responds to the same content. If server 106 has a profile of this user, the information can be customized and tailored to the specific profile.
Incorporated by reference herein
U.S. Ser. No. 09/686,572 (attorney docket US 000183) filed Oct. 10, 2000 for Tom Dubil et al., for CONTROL CODES FOR PROGRAMMABLE REMOTE SUPPLIED IN XML FORMAT. This document relates to an Internet service that control codes available for use on a programmable universal remote. The remote controls CE equipment through IR or RF commands. A server supplies the control codes as XML data that gets processed at the receiver's set top box or PC, or the remote itself, for being properly installed on the remote.
U.S. Ser. No. 09/427,821 (attorney docket PHA 23,786) filed Oct. 27, 1999 for Joost Kemink et al., for PDA HAS WIRELESS MODEM FOR REMOTE CONTROL VIA THE INTERNET. This document relates to combining a PDA with a wireless modem to enable remote control of CE equipment via the Internet and a local home server.
U.S. Ser. No. 09/128,839 (attorney docket PHA 23,469) filed Aug. 4, 1998 for Jan van Ee et al., for REMOTE CONTROL HAS ANIMATED GUI. This document relates to a remote control device for remote control of home theater equipment. The device has a display with a touch screen representing a GUI. User-activation of the GUI causes its appearance to change. The change is effected through animation. Animation is the simulation of movement created by displaying a series of bitmaps. The animation lets the user perceive the change as a smooth transition. Thus the impression is avoided of an abrupt confrontation with a new lay-out.
U.S. Ser. No. 09/129,300 (attorney docket PHA 23,470) filed Aug. 5, 1998 for Jan van Ee et al., for GUI OF REMOTE CONTROL FACILITATES USER-FRIENDLY EDITING OF MACROS. This document relates to a remote control device for a home theater. The device has a macro creation/editing mode with authoring tools on the remote's GUI. One of the editing tools lets the user move a selected macro step visibly up or down the list of steps on the GUI. | A remote control device comprises a telephone and a touch screen functionality to enable the user to participate in interactive TV programs and interact with advertisements. This approach is independent of the infrastructure delivering traditional content, and independent of the configuration of an STB. | 7 |
FIELD
[0001] The specification relates to pleatable materials, or fabrics, for use in filtration, and more particularly for use as pleated “filter bags” in baghouse-type dust collectors, for example.
BACKGROUND
[0002] A dust collector is an equipment to remove particles in an industrial fume. Typically the collector contains between hundreds to thousands of cylindrical elements referred to as bags. The bags are made of a filtration fabric that is porous. As the gas flows through, the porous filtration fabric collects particles. The particles can form a cake on the surface after minutes of operation, and the bags are typically cleaned by a reversed jet.
[0003] One of the important parameters of the filtration fabric is the filtration efficiency. The efficiency of filtration of bags is related to the total surface area. Typically, if the surface area is increased, then the velocity of gas and particles going through the fabric will be reduced, which decreases the probability of undesired particles going through the fabric and can consequently reduces the particle emissions. Moreover, a higher surface area can reduce the probability of particles getting embedded into the fabric in a manner where they resist the reversed jet, thereby increasing the lifespan of the filter. It is also possible, by increasing the surface area, to increase the capacity of a dust collector. It is thus generally sought to increase the surface area of the bags in dust collectors, where possible.
[0004] Typically, pleated bags have a greater surface area than non-pleated bags (i.e. simply cylindrical bags). Using pleated bags instead of non-pleated bags is thus one way of increasing the surface area without necessarily increasing the overall size of the dust collector system. In many cases, replacement of non-pleated bags by pleated bags can increase the surface area by two to three times.
[0005] Pleated bags can be made using a pleatable material which keeps its shape after pleating. The pleating can be done with a pleating machine. Some pleating machines operate at room temperature.
[0006] Alternately, for some materials which require thermosetting to retain their pleats, pleating machines having heating blades are used to fold the fabric and keep pressure on the pleats until the fabric is cooled back to room temperature. Heretofore, such processes have been used with polymers that can be thermally formed and have a relatively small density.
[0007] Some materials that are not thermally formable per se can be made so by adding a thermo-setting resin. An example of this is fiberglass felt impregnated with phenolic resin. The temperature of blades allow setting of the phenolic resin which subsequently acts to maintain the shape of the pleats. The reaction being irreversible, the pleats subsequently keep their shape even at high temperature.
[0008] However, even given the state of the art, some filtration materials could not be pleated by the known means and therefore remained known as being unpleatable. Nevertheless, given some desired characteristics, at least one of these ‘unpleatable’ filtration materials remained a popular choice for some specific applications despite the fact that it was not available in pleated form. There thus remained a strong need for an equivalent to such ‘unpleatable’ materials in pleated form due to the many advantages of pleats in filtration. This called for improvement.
SUMMARY
[0009] As it will appear from the description below, a filtration material such as a PTFE felt covered by an E-PTFE membrane, which was traditionally known as unpleatable, can now be made pleatable by felting with a pleatable scrim, more particularly a pleatable metallic scrim. There are many metals which are pleatable when provided in apertured sheets, and the pleatability of a metallic scrim can take precedence on the pleatability of both the felted PTFE and the E-PTFE membrane. Felting by hydro-entanglement (spunlacing) can be better suited than needle-felting when using a metallic scrim.
[0010] In accordance with one aspect, there is provided a pleatable filtration material comprising a felt having PTFE fibers felted onto a pleatable metallic scrim, a permeability of at least 20 l/dm 2 /minute at 12 mm of water gauge and a weight between 100 and 1000 g/m2, the felt having a density between 150 and 1000 g/m 2 and a permeability greater than that of the scrim and between 20 and 250 l/dm 2 /minute at 12 mm of water gauge; and a membrane laminated onto the felt, made of E-PTFE and having a permeability of between 3 and 75 l/dm 2 /minute at 12 mm of water gauge, preferably between 12 and 50 l/dm 2 /minute at 12 mm of water gauge; wherein the filtration material can be pleated using a traditional pleater at room temperature and thenceforth retain its pleats.
[0011] In accordance with one aspect, there is provided a process of making a pleatable filtration material comprising felting PTFE fibers onto a pleatable metallic scrim having resistance characteristics at least comparable to that of the PTFE fibers, a permeability of at least 20 l/dm 2 /minute at 12 mm of water gauge and a weight between 100 and 1000 g/m2, until a felt density between 150 and 1000 g/m 2 in addition to the density of the scrim and a permeability greater than that of the scrim and between 20 and 250 l/dm 2 /minute at 12 mm of water gauge are reached; and laminating an E-PTFE membrane having a permeability of between 3 and 75 l/dm 2 /minute at 12 mm of water gauge, preferably between 12 and 50 l/dm 2 /minute at 12 mm of water gauge onto a face of the felted PTFE fibers.
[0012] In accordance with one aspect, there is provided a pleated filter bag for use in a bag house dust collector, the filter bag being elongated and comprising a longitudinal hollow center with an open end, and a pleated filter wall transversally circumscribing the hollow center, the pleated filter wall having a felt felted onto an apertured and pleatable scrim and having a permeability lower than a permeability of the scrim and appropriate for filtration applications, and a membrane having a permeability substantially lower than the permeability of the felt and covering the felt on the outer side thereof facing the hollow center, wherein all of the scrim, the felt, and the membrane are resistant to a harsh filtration environment of the dust collector.
[0013] In accordance with another aspect, there is provided a filter fabric construction which incorporates a pleatable scrim to the base felt. The pleatability of the scrim takes precedence on the pleatability of the remaining components of the filter fabric, thereby rendering the filter fabric pleatable. This construction, or associated production method, can make pleatable a material such as PTFE, which was traditionally known as non-pleatable.
[0014] In accordance with another aspect, there is provided a pleatable filtration fabric having an E-PTFE laminated PTFE felt. This filtration fabric is made pleatable while at least substantially maintaining the thermal and chemical resistance characteristics of the PTFE by making the PTFE felt with a pleatable, heat-resistant and chemical-resistant scrim. The pleatability of the metallic scrim takes precedence in the combination and makes the entire material pleatable.
[0015] It will be understood that in the instant specification, the expression “pleatable” is to be understood in the context of operability in filtration. A pleatable filtration element will retain its pleats for a reasonable lifespan in the context of a normal or recommended use. For instance, a felt of polyester with a polyester scrim can be viewed as a non-pleatable fabric, whereas spunbounded polyester, which is denser and stiffer, can be viewed as pleatable.
DESCRIPTION OF THE FIGURES
[0016] In the appended figures,
[0017] FIG. 1 is a perspective view, fragmented, showing an example of a felt having a pleatable scrim.
DETAILED DESCRIPTION
[0018] One example of a material which was still used in unpleated form is polytetrafluoroethylene (PTFE), at least partly because of its exceptional thermal and chemical resistance characteristics which made the only viable choice for some harsh environments. An example of an application where unpleated PTFE-based bags were still used is dust collectors of waste incineration facilities. Incinerated wastes typically contain plastics which emit aggressive chemicals such as HCl, H2SO4, and HF during combustion. PTFE was appreciated for resisting to the combination of high temperatures (˜150 to 260° C.) and aggressive chemicals present in such waste incineration gaseous by-products. In applications such as waste incineration where tolerated emission levels were quite low, the PTFE fabric can be covered by a membrane to get a more efficient degree of filtration. A porous expanded PTFE membrane (E-PTFE) can be used to this end, laminated on the PTFE felt.
[0019] Tests attempting to pleat a PTFE felt (with or without catalyst) with a PTFE scrim failed. After pleating, the shape was not kept in a satisfactory way. Further, adding resins to the PTFE was found inefficient, at least partly due to the lack of adhesion and wetting by many of the tested resins on PTFE fibers.
[0020] The mere continued use of non-pleated PTFE filtration bags in dust collectors of applications such as waste incineration facilities, in itself demonstrates the former unavailability of this material in pleated form, considering the strong incentives for using pleated bags instead of cylindrical bags.
[0021] As will be detailed below, it will be understood how such materials and others can now be pleatable by felting the fabric onto a pleatable scrim. A type of pleatable scrim which can be used in making a PTFE felt pleatable is a metallic scrim.
[0022] FIG. 1 shows an exemplary sample of a PTFE felt spunlaced onto a metallic scrim. In this example, the metallic scrim is a square steel screen. As shown in the cut-out portion on the bottom and left-hand side corner of the sample, the metallic scrim is sandwiched between two layers of PTFE felt. In fact, during hydro-entanglement of the PTFE fibers, the fibers are placed on one side of the scrim, and partially pass through it, to the other side. The right-hand side of the sample is shown pleated. The E-PTFE membrane (not shown in the illustration), can later be laminated onto one face of the PTFE felt with metallic scrim. The PTFE felt can act as a support layer for the E-PTFE membrane which has a permeability substantially lower than the permeability of the felt. In use, the E-PTFE membrane faces the outside of the filtration bag and determines the relatively low permeability of the filtration material. The felt can thus be used to provide a cushioned support to the membrane, and, in combination with the metallic scrim, gives mechanical resistance to the membrane which acts as the actual “filter” during use but which is not practically usable alone. In fact, in many applications, the stresses which would be imparted to the E-PTFE membrane by the scrim during use if it was adhered directly thereto instead of being supported via felt, would result in an E-PTFE membrane having a very short useful life. The metallic scrim additionally provides pleatability to the filtration material because its higher pleatability takes precedence in the assembly.
[0023] The felt can be made of expanded porous or non-expanded PTFE fibers. The felt can be made by spunlacing the fibers onto the metallic scrim by a water jet—a process commonly referred to as hydro-entanglement. Hydro-entanglement can allow to avoid or reduce damage to the metallic scrim which could result if using conventional needle felting instead. The felt can have a density between 150 and 1000 g/m 2 , preferably between 250 and 700 g/m 2 , and a permeability between 20 and 250 l/dm 2 /minute at 12 mm of water gauge, preferably above 100 l/dm 2 /minute, for example.
[0024] The metallic scrim can be made of galvanized steel, stainless steel, aluminum, aluminium alloy, bronze, brass, copper, copper-based alloy, nickel, nickel-based alloy, or any suitable metal or alloy, provided it has suitable pleatability and resistance, and that it is ductile enough to be pleated without breaking. The metal can be a woven mesh, a punched metal sheet or any method that will create a metal sheet with suitable apertures in it. The permeability of the material should be greater than the permeability which is desired of the felt, preferably at least 20 l/dm 2 /minute at 12 mm of water gauge. The weight of the metal scrim can be between 100 and 1000 g/m 2 , preferably between 300 and 700 g/m 2 for example. Metallic scrims of various known types of metals can have chemical and temperature resistance characteristics suitable for harsh applications.
[0025] The felted support layer can be treated with a binder prior to lamination of the membrane, or the binder can be omitted. The fibers of the felt can act in a binding manner in certain applications. If used, the binder can be a fluorinated ethylene propylene copolymer (FEP) or a hexafluoropropylene-tetrafluorethylene copolymer, for example, or any other suitable binder. The binder can be provided at a concentration of between 25-50% by weight in a liquid suspension, and be either sprayed on a selected side of the support layer or transferred thereon using a roll. The material can then be heated in an oven at ˜120 to 240° C., to evaporate the solvent. After evaporation, the weight of transferred solid binder can represent a relative weight of between 1% and 10% (relative to the weight of the fabric).
[0026] The membrane, which can be made of commercially available E-PTFE, preferably has a permeability between 3 and 75 l/dm 2 /minute at 12 mm of water gauge, more preferably between 12 and 50 l/dm 2 /minute at 12 mm of water gauge. The membrane can be laminated on the side having the binder at a temperature of 270° C.
[0027] It will be noted that in some instances, PTFE felt for use in applications such as incinerators can have particles of catalyst deposited on the surface or embedded into the PTFE fibers. This can be desirable in a pleatable fabric and typically does not affect pleatability. For example, some catalysts help reducing emissions of dioxin, furan or nitrous oxide from waste incineration. The catalyst typically is typically provided a volume less than 20% of the volume of the PTFE fibers. Examples of catalysts include titanium dioxide (TiO 2 ), iron and cobalt (provided in the form of oxides), nickel, platinum and palladium. Other examples of catalysts include zeolith, copper oxide, tungsten oxide, aluminum oxide, chromium oxide, gold, silver, rhodium etc. If used, the catalyst should be provided in a particles size of less than 10 microns, but can be of any suitable shape, such as spheres, whiskers, plates, flakes, etc.
[0028] A resulting pleatable filtration material, or fabric, can include PTFE fibers spunlaced to a steel scrim, covered by a membrane. Such a fabric can be pleated using a traditional pleater operating at room temperature. The use of a pleatable metallic scrim can render the use of heated pleater blades unnecessary. An exemplary embodiment thereof is provided below:
EXAMPLE 1
[0029] PTFE fibers are spunlaced onto a 400 g/m 2 stainless steel scrim by hydro-entanglement. After entangling the total weight is 800 g/m 2 . The permeability of the material at this step is about 200 l/dm 2 /minute. The resulting felted support material is then sprayed with a suspension of FEP particles to add about 25 g/m of FEP particles after drying at 150° C. Then, an E-PTFE membrane is laminated thereon with the temperature of the FEP particles raised to 270° C. The resulting filtration material has a weight of 825 g/m 2 , and a permeability between 15 and 30 l/dm 2 /minute at 12 mm of water gauge, and is pleatable at room temperature.
EXAMPLE 2
[0030] Titanium dioxide particles of less than 10 microns in size are mixed with a PTFE dispersion. The titanium dioxide can correspond to 1-90% by volume, preferably 25-85% by volume, for example. The paste is extruded and calendered to form a tape. The tape is slitted along the length, expanded and processed over a rotating pinwheel to form fibers. These fibers with catalyst on the surface are spunlaced onto a 500 g/m2 stainless steel 316 scrim by hydroentanglement. After entangling the total weight is 900 g/m2. The E-PTFE membrane is laminated directly on the surface of the catalytic felt, the fibers acting as the binding agent. The resulting material has a weight of 900 g/m2, a permeability between 15 and 30 l/dm2/min at 12 mm of water gauge and is pleatable at room temperature.
[0031] It is to be understood that above example is given for illustrative purposes only. Alternate embodiments can be realized. For instance, thicker or thinner fabrics can be realized using more or less spunlaced PTFE, and different E-PTFE membranes. The pleatable metallic scrim can be applied to materials other than PTFE. Further, other scrim materials than metals can have similar pleatability and resistance characteristics. The use of a catalyst is optional. Given the above, the scope is indicated by the appended claims. | The pleated filter bag, which can be used in a bag-house type dust collector, is elongated and has a longitudinal hollow center with an open end, and a pleated filter wall circumscribing the hollow center. The pleated filter wall has a felt such as PTFE fibers felted onto an apertured and pleatable scrim which can be made of metal, and having a permeability lower than a permeability of the scrim. A membrane of lower-permeability material, such as an E-PTFE membrane, covers the support felt on the outer side of the bag. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation of U.S. Ser. No. 10/229,313, filed Aug. 27, 2002 (now U.S. Pat. No. 6,698,335), which is a continuation-in-part of U.S. Ser. No. 09/838,091, filed Apr. 19, 2001 (now U.S. Pat. No. 6,439,107), which is a continuation-in-part of U.S. Ser. No. 09/703,993, filed Nov. 1, 2000 (now abandoned) which is a continuation in part of U.S. Ser. No. 09/567,676, filed May 9, 2000 (now abandoned) which is a continuation in part of U.S. patent application Ser. No. 09/426,210, filed Oct. 25, 1999 (now U.S. Pat. No. 6,058,830), which is a continuation in part of U.S. patent application Ser. No. 09/149,842, filed Sep. 8, 1998 (now U.S. Pat. No. 5,970,852), which is a continuation of U.S. Ser. No. 08/813,463 filed Mar. 10, 1997 (now U.S. Pat. No. 5,813,321), each of the above being incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to outdoor cooking devices and cooking accessories and more particularly to a natural gas fired outdoor cooker that is supplied with a source of fuel such as butane or propane from a canister and that includes a stand, pot, and pot liner, the improvement including a special configuration of the burner and a connected table that enables a user to quickly support a pot liner or basket upon the table after it is removed from the pot of boiling liquid.
2. General Background of the Invention
A number of outdoor cookers have been sold commercially for a number of years and are admitted as “prior art” type burners. These “prior art” burners have traditionally included a metallic frame that supports a burner nozzle, such as a cast iron burner nozzle. Such burner nozzles are commercially available and are used to fire most natural gas fired hot water heaters.
Examples of these prior art type outdoor cooking devices can be seen in the Jan. 1, 1996 brochure of Metal Fusion, Inc., of Jefferson, La. Patents have issued naming Norman Bourgeois as inventor that relate to burners and related cooking apparatus. Examples include U.S. Pat. No. 5,065,735 for a “Convertible Burner Apparatus” that features different primary burner frames and legs that can elevate the burner frames. Other Bourgeois patents that relate to cooking devices include the aforementioned U.S. Pat. Nos. 5,813,321; 5,970,852; and 6,058,830.
The burner nozzle can be a cast iron hot water heater type burner nozzle or a jet burner arrangement that uses a single outlet centered in a cylindrically-shaped, vertically oriented metallic tube. The most common version of the prior art “jet burner” arrangement is seen in Metal Fusion's catalog as Model No. 90PK. Another version of this type of cooker includes two spaced apart circular rings connected with struts and having a cylindrically-shaped wind guard or shroud. This type of prior art burner can be seen for example as Metal Fusion Model Nos. 82PK, 83PK, 85PK, 86PK, and 86PKJ.
For cooking some food items such as poultry items, it is sometimes desirable to fry the object in a basket that can be lifted from the pot. An example of this type of “prior art” arrangement is seen in the 1996 Metal Fusion catalog as Model No. 32TPK. For a combination cooking arrangement that includes a burner, pot and liner, the user typically places the poultry item in the basket and lowers it into boiling oil using a bail. In the prior art, bails have often been detachable from the basket so that the user can lower the basket into the pot and the contained boiling oil and then remove the handle or bail therefrom. This allows the user to eliminate the transfer of heat from the basket to the handle during the elongated cooking process.
A number of patents have issued that relate to cooking devices and utensils for use in combination with cooking vessels. The Walker U.S. Pat. No. 4,735,135 provides a utensil assembly and kit including same for cooking vessels used in preparing and supporting combustibles above the bottom of the cooking vessel and away from its inner walls. The utensil kit comprises a base supported above the bottom of the cooking vessel, a plurality of support attachments separately detachable and interchangeably mountable on the base for supporting selected combustible products, and releasable latch mechanism having two parts, one part disposed on the base, and the other part is disposed on each of the support attachments for engaging the base. One of the utensils is a poultry support attachment that fits inside the cavity of a chicken or other poultry enabling it to be positioned upright.
The Rappaport U.S. Pat. No. 3,053,169, discloses a poultry supporting device that sits upon a base in the form of a pan.
A rotisserie cooking arrangement is disclosed in the French Patent 2685862.
A roasting support for fowl is disclosed in U.S. Pat. No. 5,106,642. The apparatus includes a longitudinally extending rod that extends through the center of the turkey having an eyelet at its upper end.
A roaster for poultry and meat is disclosed in U.S. Pat. No. 5,301,602. The apparatus includes a vertical roasting apparatus wherein a predetermined amount of liquid for generating the moisture required to produce a high quality and flavorful roasting of the meat is included in a reservoir formed within the support structure itself and disposed internally of the poultry or meat being roasted.
A vertical spit for displaying roasting or warming is disclosed in U.S. Pat. No. 5,442,999.
A combination outdoor cooker and smoker is disclosed in U.S. Pat. No. 5,531,154. The apparatus includes a cooker having a gas burner coupled to an external gas source through a control valve by a gas supply conduit.
An Austrian patent 217592 discloses a cooking device that has a central member upon which a turkey or chicken is supported during the cooking operation.
British patent 2205734A discloses a device for use in preparing and cooking kebabs that includes walls which are interconnected to define a tube member and into which a first end wall is slidably received to further reinforce the shape formed by the sidewalls and whose end position is determined by the engagement of lips projecting inwardly from the sidewalls. The sidewalls are appertured longitudinally for receiving a knife to cut food within the tube member.
Issued patents to Barbour (U.S. Pat. Nos. 5,758,569 and 5,896,810) disclose a cooking apparatus directed to the frying of poultry items such as turkeys.
Several patents have issued that are directed to a cooker or pot having a spigot provided on the pot wall that enables liquid to be withdrawn from the pot via the spigot. An example of such an early patent is the Saroni U.S. Pat. No. 57,577 entitled “Apparatus for Steaming Vegetables.” In the Saroni 577 patent, a spigot B is provided for withdrawing liquid from the receptacle or pot.
The Paterson U.S. Pat. No. 74,123 discloses in FIG. 1 a spigot mounted on the wall of a pot.
The Durham U.S. Pat. No. 123,876 discloses a boiler (see FIGS. 1 and 3 ) in the form of a pot having handles and a lid H. The Durham '876 patent states that one or more of the lower components are using for cooking solids, and the others are either for soup or other liquid, the latter C or either of them being provided with a tap D at the bottom for drawing off the contents.
The Goodwyn patent provides a cooking vessel. A faucet B is provided at the lower end of the boiler A.
The Harper U.S. Pat. No. 1,054,114 discloses a furnace that includes a vat that can be fastened to the top of the fire box by means of a sleeve D formed integral therewith and adapted to fit over the smoke pipe E. This vat is provided with a cover D′ and also an outlet pipe E having a spigot E′.
A cooking vessel is disclosed in the Clayton U.S. Pat. No. 1,272,222 that includes a cooking vessel 10 having an outlet nipple 11 in which is rotatably mounted on a valve plug 12 . This valve structure enables the liquid to be easily drawn off.
The Jobe U.S. Pat. No. 1,390,908 discloses a cooking vessel that has an outer pipe 20 that has one end communicating with the inner receptacle for drawing liquids therefrom, the pipe extending through the outer receptacle and equipped with a valve 21 .
The Austin U.S. Pat. No. 1,827,131 provides a pot drain in the form of pipe 12 that is fitted with a cap 13 .
The Baker U.S. Pat. No. 2,350,335 discloses a brewer or cooker that has a drain valve 7 adjacent its lower end through which brewed coffee may be withdrawn.
The Shipman U.S. Pat. No. 3,838,680 discloses a combination heating and serving assembly having a drainage outlet or spigot 32 by which the liquid contents of the container may be drawn off from time to time.
One of the problems with outdoor cookers is the handling of very large pots that contain a high volume of cooking fluid such as vegetable oil. It is desirable that such an outdoor cooking apparatus have good stability to support the very heavy and often tall pot during cooking, and during placement of or removal of the pot, liner or both from the burner. Further, the cooking fluid is desirably reused for certain cooking fluids such as vegetable oils. One solution is to drain the pot, yet also provide for drainage without removal from the burner. However, the burner must enable such drainage and still provide a safe, stable cooking platform for very large capacity cooking pots.
BRIEF SUMMARY OF THE INVENTION
The present invention includes a burner frame having a base for engaging an underlying support surface, the burner having a nozzle for generating a high intensity flame for use in cooking, and a supply hose for supplying propane to the burner. The burner frame has a support surface for cradling a pot.
A pot is provided that includes a flat bottom portion and cylindrically-shaped continuous side walls, the pot having a generally cylindrically-shaped interior for receiving a basket. The basket or liner removably fits the pot interior. The basket can include a base that registers against the bottom of the pot and a vertically extending portion adjacent to the pot wall that connects to a bail.
The burner frame includes a ring that is supported above the bottom of the pot on the exterior of the pot for engaging the sidewall of the pot should the pot be tipped.
The upper ring is supported by a plurality of generally “L” shaped struts that extend from the upper ring downwardly along a generally vertical path and then horizontally to cradle the bottom of the pot.
The upper ring is specially configured as will be described more fully hereinafter to enable drainage of the pot and without removal from the burner.
As shown in FIGS. 1-3 , the cooking apparatus provides a plurality of food holding inserts that fit the pot interior, wherein a first insert is selectively connectable to and supported by a second insert and wherein the second insert has an upper end with a connector and is configured to extend between the pot bottom portion and the pot upper end portion and support a food item when it is not supporting nor connected to the first insert. The cooking apparatus also provides a lifting hook that selectively connects to or disconnects from the connector of the second insert.
BRIEF DESCRIPTION OF THE SEVERAL VIEW OF THE DRAWINGS
For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:
FIG. 1 is a perspective view of the preferred embodiment of the apparatus of the present invention;
FIG. 2 is a partial perspective view of the preferred embodiment of the apparatus of the present invention illustrating the basket, steam plate, and bail;
FIG. 3 is a partial perspective of the preferred embodiment of the apparatus of the present invention illustrating the basket portion thereof;
FIG. 4 is a fragmentary perspective view of the preferred embodiment of the apparatus of the present invention illustrating the burner portion thereof;
FIG. 5 is a fragmentary sectional elevation view of the burner of FIG. 4 ;
FIG. 6 is a fragmentary sectional elevation view of the burner of FIG. 4 ;
FIG. 7 is a sectional elevation view of the preferred embodiment of the apparatus of the present invention illustrating the burner, pot, and basket portions thereof during steaming;
FIG. 8 is a sectional elevation view of the preferred embodiment of the apparatus of the present invention illustrating the burner, pot, and basket portions thereof during boiling;
FIG. 9 is a perspective view of the preferred embodiment of the apparatus of the present invention showing an alternate burner construction;
FIG. 10 is a top view of the burner of FIG. 9 ;
FIG. 11 is a sectional view taken along lines 11 - 11 of FIG. 10 ;
FIG. 12 is a perspective view of an alternate embodiment of the apparatus of the present invention;
FIG. 13 is a sectional view taken along lines 13 - 13 of FIG. 12 ;
FIG. 14 is a sectional view taken along lines 14 - 14 of FIG. 12 ;
FIG. 15 is an exploded perspective view of a third embodiment of the apparatus of the present invention;
FIG. 16 is a perspective view of the third embodiment of the apparatus of the present invention;
FIG. 17 is a partial perspective view of the third embodiment of the apparatus of the present invention;
FIG. 18 is another partial perspective view of the preferred embodiment of the apparatus of the present invention;
FIG. 19 is a partial sectional elevation view of the third embodiment of the apparatus of the present invention;
FIG. 20 is a partial perspective view of the third embodiment of the apparatus of the present invention;
FIG. 21 is a perspective view of a fourth embodiment of the apparatus of the present invention;
FIG. 22 is a partial perspective view of the fourth embodiment of the apparatus of the present invention;
FIG. 23 is a partial perspective view of the fourth embodiment of the apparatus of the present invention illustrating the burner portion thereof;
FIG. 24 is a fragmentary view of the fourth embodiment of the apparatus of the present invention illustrating a portion of the burner and a portion of the pot illustrating its valved drain line;
FIG. 25 is a partial perspective view of the fourth embodiment of the apparatus of the present invention;
FIG. 26 is a perspective view of a fifth embodiment of the apparatus of the present invention; and
FIG. 27 is a partial perspective view of the fifth embodiment of the apparatus of the present invention illustrating the burner portion thereof.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides an outdoor cooking apparatus designated generally by the numeral 10 in FIG. 1 . The apparatus 10 includes a burner 11 , pot 12 , supply valve 13 , a commercially available flexible hose for supplying propane or like fuel for firing the burner 11 , and a basket 14 (see FIGS. 2-3 ) that can be lowered into the interior 15 of pot 12 . In FIGS. 4-8 , burner 11 includes a lower ring 16 and an upper ring 17 . Burner 11 has a nozzle or jet surrounded by cylindrically-shaped wind guard 22 .
The rings 16 , 17 are connected with a plurality of struts 18 . Each strut 18 includes radially extending, inclined lower strut section 19 , upper strut section 20 , and vertical center strut section 21 . Each of the lower strut sections 19 is linear in shape, and inclined to form a connection between the lower or base ring 16 and the bottom of central strut section 21 (see FIG. 6 ).
Upper strut sections 20 are generally “ell” shaped having a lower end portion 23 that forms a connection with the upper end of central strut section 21 and an upper end 24 that forms a connection with upper ring 17 .
The “ell” shaped upper strut sections 20 include upper linear section 24 , lower linear section 23 , and bend sections 25 , 26 . This configuration provides both a base for holding the bottom surface 27 of pot 12 and a vertically extending portion that envelopes the lower end of pot sidewall 28 .
In a preferred embodiment, the ring 17 can be positioned, for example, about 2-8 inches above the bottom surface 27 of pot 12 . Further, the upper ring 17 has an inside diameter indicated as 29 in FIG. 7 that closely approaches the outside diameter 30 of pot 12 . A clearance of about ½-1½ inches is provided in between the inside of ring 17 and the outside of pot wall 28 during use.
In FIGS. 1-3 , basket 14 includes a wire basket frame base 31 that can be, for example, in the form of a plurality of connected (e.g., welded) wire members arranged in a cross (see FIG. 3 ).
In FIGS. 2-3 , basket 14 includes a base comprised of a pair of linear intersecting members 32 , 33 , a pair of vertical members 34 , 35 and a bail 36 . The base can have feet for spacing it from the bottom 27 surface of pot 12 . Each vertical member 34 , 35 has a hook 37 , 38 respectively for connecting to the lower ends 39 , 40 of bail 36 , as shown in FIG. 2 . Bail 36 can be trapezoidal in shape, having handle portion 51 , sides 52 , 53 and cross beam 54 . The enlarged handle 51 enables a user to grip with both hands.
Steamer plate 41 can optionally be placed upon basket 14 if food items are to be steamed. Plate 41 has a generally circular shape, providing peripheral edge 42 and central opening 43 . Plate 41 is preferably perforated providing an array of openings therethrough that enable steam to access all surfaces of a food item that is placed on the upper surface 45 of plate 41 . Drippings from food items can flow through the openings as well.
Support 46 extends upwardly from base 31 of basket 14 . Support 46 has a dual function of holding steamer plate 41 as shown in FIGS. 2 and 7 and of supporting a food item such as chicken, turkey or other selected item as shown in FIG. 8 .
A pair of laterally extending posts 47 , 48 support the peripheral edge 42 of steamer plate 41 when the steamer plate is assembled to the basket 14 . Central opening 43 of steamer plate 41 rests upon support 46 when the steamer plate is put in an operational position. The steamer plate is thus supported at its periphery with posts 47 , 48 and at its center with support 46 . Steamer plate 41 has peripheral slots at 49 , 50 that fit vertical members 34 , 35 respectively.
The apparatus of the present invention thus provides a dual function cooking apparatus that enables a user to either steam food products such as crabs, lobsters, clams and the like, or boil food items such as fish, shellfish, or poultry items.
FIGS. 9-11 show an alternate embodiment of the apparatus of the present invention designated generally by the numeral 55 in FIGS. 12 and 17 - 18 .
Outdoor cooking apparatus 55 includes a burner for supporting pot 12 . Burner 55 ( FIGS. 9-11 ) includes upper ring 56 and a plurality of horizontal struts 57 - 59 . Vertical struts 60 - 62 are connected integrally to horizontal struts 57 - 59 respectively. As shown in FIGS. 9-11 , a plurality of legs 63 , 67 , 71 are attached to horizontal struts 57 , 58 , 59 respectively. Each leg 63 , 67 , 71 is formed of a pair of straight sections and a bend section. The leg 63 includes straight sections 64 and 66 connected by bend 65 . The leg 67 includes straight sections 68 , 70 connected by bend 69 . The leg 71 is similarly configured to legs 63 and 67 .
A cylindrical flue 72 is placed at the vertical central axis 91 of burner 55 as shown in FIGS. 10 and 11 . The cylindrical flue 72 attaches to each of the legs 63 , 67 , 71 by welding for example. Each leg 63 , 67 , 71 attaches to a horizontal strut 57 , 58 , 62 , preferably by welding. Each of the vertical struts 60 , 61 , 62 attaches to upper end 56 by welding, for example. A fuel supply line 73 is used to supply combustible gas such as propane or butane to nozzle 75 . The nozzle 75 is preferably attached to the vertical bore 74 of cylindrical flue 72 by welding or like means known in the art.
Circular plate 76 is attached to the inner end portions of horizontal struts 57 , 58 , 59 as shown in FIGS. 9-11 . This attachment of plate 76 to horizontal struts 57 , 58 , 59 can be by welding at welds 77 for example.
In FIG. 11 , the apparatus 55 of the present invention is shown in operating position wherein pot 12 occupies a position on top of the horizontal struts 57 , 58 , 59 . A flame 78 extends upwardly from nozzle 75 . The nozzle 75 can be ignited when propane, butane or like gas is transmitted to the nozzle 75 via pipe line 73 using a match, or like starter. Flame 78 strikes the bottom of plate 76 diverting flame 78 laterally to provide even distribution of heat to the bottom of pot 12 . This distribution of the flame 78 outwardly and laterally away from plate 76 is indicated schematically by arrows 79 in FIG. 11 .
FIGS. 12-14 show an alternate embodiment of the apparatus of the present invention designated generally by the numeral 81 in FIGS. 12-14 . Burner apparatus 81 includes a frame 82 comprised of a plurality of beams. Frame 82 can be of welded steel construction, for example. Frame 82 thus includes beams 83 , 84 that are parallel to each other and central beam 85 that is generally perpendicular to the beams 83 , 84 .
At the extreme end portions of frame 82 , beams 86 , 87 extend between respective end portions of beams 83 , 84 as shown in FIG. 12 . Each of these end beams 86 , 87 is connected to a leg 88 or 89 . As shown in FIG. 13 , attachments 93 (for example, welded attachments) form a connection between each leg 88 , 89 and frame 82 at beams 86 , 87 respectively.
In FIGS. 13 and 14 , each leg 88 , 89 is comprised of a horizontal member 90 and a pair of inclined members 91 , 92 .
In the embodiment of FIGS. 12-14 , a pair of burners 94 are provided, each comprising a cylindrically shaped shroud 95 , a contained burner element 96 positioned within the shroud 95 as shown in FIGS. 13 and 14 and grate members 98 that support shroud 95 and its contained burner element 96 . A ring 97 forms an interface between frame 82 and the plurality of grate members 98 . Rings 97 can be welded to the beams at the top of frame 82 . In FIG. 12 , ring 97 on the left hand side of FIG. 12 is welded to beams 83 , 84 , 85 and 86 . The ring 95 on the right hand side of FIG. 12 is welded to beams 83 , 84 , 85 , and 87 . Grate members 98 are welded to ring 97 at attachments 102 . Grate members 98 are also connected at attachments 103 to shroud 95 . The attachments 103 can be welded connections, for example.
FIGS. 15-20 show a third embodiment of the apparatus of the present invention, designated generally by the numeral 104 in FIGS. 15 and 16 . Cooking apparatus 104 is in the form of a combination smoker/burner. This apparatus enables a smoker to be used with the burner that is shown and described with respect to the first and second embodiments of FIGS. 1-14 . Smoker apparatus 104 provides a lower section 105 , middle section 106 , and upper section 107 . The upper section 107 basically functions as a cover. The middle section 106 is a cooking chamber. The lower section 105 can be used to contain a bowl that has a liquid that can include seasoning. Alternatively, the sections 105 , 106 , 107 can be assembled as a free standing smoker separate from burner 11 wherein the bowl 119 can be filled with charcoal.
Lower section 105 is specially configured to mate with and be supported by burner 11 . The lower section 105 provides a larger cylindrical side wall 109 and a smaller cylindrical side wall 113 . A tapered annular wall 114 joins the larger cylindrical side wall 109 and the smaller cylindrical side wall 113 as shown in FIG. 19 . A bottom panel 112 connects to the lower end of the smaller cylindrical side wall 113 . When not in use upon burner 11 , the smoker sections 105 , 106 , 107 can be supported by any means known in the art such as for example, a plurality of legs 115 or a separate base that is not a burner and that fits the contours of bottom 112 , small side wall 113 , tapered annular side wall 114 , and/or larger cylindrical side wall 109 .
An access door 120 can be provided in lower section 105 as can be air vent openings 116 . The lower section 105 can provide a flat, annular flange 117 or other suitable mating surface for supporting middle section 106 . Similarly, upper section 107 is configured to fit upon the upper edge 126 of middle section 106 .
A cooking grate 118 can be supported upon one or more supports 121 provided on the interior of lower section 105 . Similarly, a plurality of supports 121 can also be provided at the upper end portion of middle section 106 for supporting a cooking grate. Handles 122 can be provided on any of the sections 105 , 106 , 107 as desired for manipulating the various sections. The cover can be provided with usual thermometer and burner 11 can provide a jet or nozzle 125 and/or a flame diffuser 124 .
It should be understood that the general concept of a smoker that includes multiple sections such as 105 , 106 , 107 is old in the art, having been sold commercially a number of years such by Brinkman and others.
FIGS. 21-25 show a fourth embodiment of the apparatus of the present invention designated generally by the numeral 130 . Cooking apparatus 130 includes a pot 131 having a pot side wall 132 that is generally cylindrically shaped and provided with a pair of handles 133 . Pot 131 provides a generally flat, circular bottom 134 and has an interior 153 that can retain items to be cooked, cooking fluid and a perforated basket 135 or liner that enables food items to be inserted into the pot interior 153 and removed therefrom when cooking is completed. The perforated basket enables draining of any cooking fluid while retaining the food items that are to be cooked such as for example, crabs, poultry items, seafood items and the like. The perforated basket 135 can be lifted using bail 136 .
Drain outlet fitting 137 is provided in pot sidewall 132 and at a lower position that is next to pot bottom 134 as shown in FIGS. 21 , 22 and 24 - 25 . The drain outlet fitting 137 has an attached valve 138 that can be opened or closed by rotating valve stem 139 . Such an outlet 137 and valve 138 can be welded e.g. to the pot 131 wall 132 . This concept of providing a drain outlet fitting 137 with an attached valve 138 is per se known, being disclosed for example in the Durham U.S. Pat. No. 123,876; the Clayton U.S. Pat. No. 1,272,222, and the Baker U.S. Pat. No. 2,350,335 each of which is hereby incorporated herein by reference. Burner 140 supports pot 131 during cooking. The burner 140 includes a lower ring 141 , an upper ring 142 , and a plurality of struts 148 , 149 , 150 that extend between the upper ring 142 and lower ring 141 as shown in FIGS. 21 , 22 and 23 . A feature of the present invention is the special burner configuration at upper ring 142 that enables fluid to be drained from pot 131 without removing pot 131 from burner 140 .
Upper ring 142 has a U-shaped section 146 defined by bends 143 , 144 , 145 . The U-shaped section 146 thus extends below upper surface 147 of upper ring 142 as shown in FIGS. 21 , 22 and 24 - 25 . The U-shaped section 46 provides a recess 151 that enables valve 138 to extend a radial distance beyond the outer periphery of upper ring 142 as shown in FIGS. 21 , 22 and 24 - 25 . The combination of drain outlet fitting 137 and valve 138 provide a flow bore 152 during use. The valve 138 can be opened for draining fluid from the pot 131 . This can be helpful when cooking with large volumes of cooking fluid such as vegetable oil that is commonly used is the cooking of poultry items such as large turkeys. After the vegetable oil that is used to cook a turkey has cooled, it can be drained easily into its original one gallon container by opening the valve 138 with a rotation of stem 139 in a counterclockwise direction. Peanut oil, for example, is commonly used for frying turkeys and is commonly sold in one gallon containers.
Each of the struts 148 , 149 , 150 has a plurality of sections. These sections include a lower section 154 and an upper section 155 . As shown in FIG. 23 , the upper section 155 is generally L-shaped being attached to upper ring 142 at connection 157 (for example, a welded connection). The strut lower section 154 is an elongated, partially inclined and partially vertical member that attaches to upper section 155 at connection 156 , a connection that can be welded, for example. The lower section 154 is attached to lower ring 141 at connection 158 , preferably a welded connection. The upper sections 155 each provide a generally horizontal upper surface portion 159 that cradles the bottom 134 of pot 131 during use as shown in FIGS. 21 and 22 .
A wind guard or shroud 160 can be provided to burner 140 as shown in FIGS. 21 and 22 , surrounding these three struts 148 , 159 and being attached thereto by welding, for example. Shroud 160 can provide a support bar 161 for supporting a burner element 162 . The burner element 162 can be a common, commercially available cast iron burner element that is fueled by a gaseous fuel such as propane or butane.
A fifth embodiment of the apparatus of the present invention is shown in FIGS. 26 and 27 , designated generally by the numeral 164 . Cooking apparatus 164 includes a burner 165 that is configured to support a pot 131 having a generally cylindrically shaped pot side wall 132 and a generally circular, flat pot bottom 134 . In FIGS. 26 and 27 , burner 165 has a plurality of struts 166 , 167 , 168 that are attached to cylindrically shaped shroud 169 . The upper end portion of each of the struts 166 , 167 , 168 support upper ring 170 which is cylindrically shaped, having cylindrical ring wall 172 . Bolted connections 171 can be used to attach upper ring 170 to each of the struts 166 , 167 , 168 . The upper ring 170 provides an upper edge 173 and lower edge 174 . Recess 175 is cut out of upper ring 170 , wall 172 . Recess 175 is surrounded by surfaces 176 , 177 and 178 as shown in FIG. 27 . The recess 175 enables the pot drain outlet fitting 137 and valve 138 to extend radially beyond the circumference of ring 170 as shown in FIG. 26 .
Each strut 166 is comprised of a plurality of sections. However, each strut 166 can be an integral structure. In FIGS. 26 and 27 , each strut 166 , 167 , 168 is comprised of a vertical upper section 179 and horizontal section 180 that cradles the pot 131 during use. Vertical section 179 and horizontal section 180 are connected at bend 186 . The horizontal sections 180 each providing a flat upper surface 181 upon which the pot 131 bottom 134 rests during cooking. Vertical section 182 extends between bend 187 and bend 188 . Inclined section 183 of each strut 166 , 167 , 168 extends between bend 188 and curved foot 184 . The curved foot 184 connects to inclined section 183 at bend 189 . An upturned end portion 185 of each strut 166 , 167 , 168 can be fastened (for example bolted using bolted connection 171 ) to lower ring 190 .
PARTS LIST
The following is a list of suitable parts and materials for the various elements of the preferred embodiment of the present invention.
Part Number
Description
10
cooking apparatus
11
burner
12
pot
13
supply valve
14
basket
15
interior
16
lower ring
17
upper ring
18
strut
19
lower strut section
20
upper strut section
21
center strut section
22
wind guard
23
lower linear section
24
upper linear section
25
bend
26
bend
27
bottom surface
28
pot sidewall
29
inside diameter
30
outside diameter
31
base
32
intersecting member
33
intersecting member
34
vertical member
35
vertical member
36
bail
37
hook
38
hook
39
end
40
end
41
steamer plate
42
peripheral edge
43
central opening
44
openings
45
upper surface
46
support
47
horizontal post
48
horizontal post
49
slot
50
slot
51
handle portion
52
side
53
side
54
transverse beam
55
outdoor cooking apparatus
56
upper ring
57
horizontal strut
58
horizontal strut
59
horizontal strut
60
vertical strut
61
vertical strut
62
vertical strut
63
leg
64
straight section
65
bend
66
straight section
67
leg
68
straight section
69
bend
70
straight section
71
leg
72
cylindrical flue
73
fuel supply line
74
vertical bore
75
nozzle
76
circular plate
77
weld
78
flame
79
arrows
80
central axis
81
burner apparatus
82
frame
83
beam
84
beam
85
beam
86
beam
87
beam
88
leg
89
leg
90
horizontal member
91
inclined member
92
inclined member
93
attachment
94
burner
95
shroud
96
burner element
97
ring
98
grate member
99
horizontal section
100
vertical section
101
bend
102
attachment
103
attachment
104
smoker apparatus
105
lower section
106
middle section
107
upper section
109
cylindrical sidewall
110
open top
112
bottom panel
113
cylindrical sidewall
114
tapered annular wall
115
leg
116
air vent opening
117
annular flange
118
cooking grate
119
bowl
120
door
121
support
122
handle
123
thermometer
124
flame diffuser
125
nozzle
126
upper edge
130
cooking apparatus
131
pot
132
pot side wall
133
handle
134
bottom
135
perforated basket
136
bail
137
drain outlet fitting
138
valve
139
stern
140
burner
141
lower ring
142
upper ring
143
bend
144
bend
145
bend
146
U-shaped section
147
upper surface
148
street
149
strut
150
strut
151
recess
152
bore
153
pot interior
154
lower section
155
upper section
156
connection
157
connection
158
connection
159
upper surface
160
shroud
161
support bar
162
burner element
164
cooking apparatus
165
burner
166
strut
167
strut
168
strut
169
shroud
170
upper ring
171
bolted connection
172
ring wall
173
upper edge
174
lower edge
175
recess
176
surface
177
surface
178
surface
179
vertical section
180
horizontal section
181
flat surface
182
vertical section
183
inclined section
184
curved foot
185
upturned end portion
186
bend
187
bend
188
bend
189
bend
The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims: | A cooking apparatus enables a user to cook bu boiling, steaming or frying food items. The apparatus includes a burner having a base that is specially shaped to cradle a pot. The pot has a valved flowline that enables the user to drain any fluid that was used for cooking (eg. water, oil, seasoned water, stock, etc.). An upper section above the support surface of the burner for engaging the sidewall of the pot should the pot be tipped inadvertently. The burner includes upper members that are supported above the bottom of the pot and a lower member that engages an underlying supporting surface. The upper pot support members include a ring with a bent, U-shaped section that extends on opposite sides of and under the valved drain flowline. The burner frame can have a plurality of circumferentially spaced radially extending legs. Radial and circumferentially spaced struts define part of the frame and are shaped and cradle the bottom of the pot and its sidewall respectively. | 0 |
FIELD OF THE INVENTION
[0001] This invention relates in general to mounting devices, and in specific to an apparatus and method for rackmounting a chassis.
BACKGROUND OF THE INVENTION
[0002] Large-scale computer systems typically include a plurality of towers or racks of computer equipment. Each rack comprises several pieces of equipment or chassis. Each chassis may comprise a board that includes processors, memory, and/or power supplies. Other chassis might include telecommunications equipment, writing equipment, networking equipment, I/O equipment, and/or user interface equipment.
[0003] Ideally, the equipment should be removably mounted into the rack. This would allow the equipment to be easily serviced and/or installed. One way that the equipment can be removably attached to the rack is to use sliding rails that are attached to the workstation. The equipment or the chassis equipment may then be attached to the sliding rails. Thus, the chassis is supported by the sliding rails and can be moved into and out of the rack by the sliding rails, which slidably extend from the rack. The sliding rails may incorporate ball bearings to more readily facilitate the sliding action. Another way that the chassis can be slidably mounted into the rack is to use a shelf. The shelf is mounted inside the rack, and rails are provided on the shelf to guide the chassis in the shelf.
[0004] Both of these designs allow the chassis to be mounted in only one orientation. Thus, the chassis mounted so that the front of the chassis faces out of the rack; the chassis cannot be mounted so that the rear is facing out of the front of the rack, unless substantial modifications are made to the mounting system. Also, such modifications utilize parts that are not common for the left and right sides and increases the cost of the mounting kit. Note that the sliding rail design may use identical parts to comprise the rails for the left and right sides, but the assembly of these parts to form the sliding rails is different such that the sliding rails are different for the left side and the right side.
BRIEF SUMMARY OF THE INVENTION
[0005] A system for mounting a device into a rack comprising a mounting shelf that is attached to the rack, a first bracket that is attached to a first side of the device, and a second bracket that is attached to a second side of the device, wherein the second side is located opposite to the first side, wherein the first bracket and the second bracket are substantially similar, and wherein the device, with the first bracket and the second bracket attached thereto, is slideably positioned into the mounting shelf and attached to the mounting shelf via the first bracket and the second bracket.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] [0006]FIG. 1 depicts mounting a chassis in a front facing orientation consistent with the teachings of the invention.
[0007] [0007]FIG. 2 depicts an embodiment of the inventive arrangement of the slide brackets and mounting shelf.
[0008] [0008]FIG. 3 depicts a slide bracket of FIGS. 1 and 2.
[0009] [0009]FIG. 4 depicts an embodiment of the invention mounting a chassis in a rear-facing orientation.
[0010] [0010]FIG. 5 depicts an alternative embodiment of the slide bracket shown in FIG. 3.
[0011] [0011]FIG. 6 depicts an alternative embodiment of the inventive arrangement using the slide bracket of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
[0012] The invention preferably comprises a folded sheet metal slide bracket assembly and a folded sheet metal mounting shelf. Two slide brackets are preferably used with one slide bracket supporting the left side of the chassis and the other supporting the right side of the chassis. The rack mount shelf is preferably connected to the rack through the use of screws and mounting holes. The slide bracket is preferably attached to the chassis by screws through holes and provides alignment and final positioning of the chassis within the rack.
[0013] The slide bracket of the invention can be mounted on either side of the chassis. This allows the chassis to be mounted with either the front or rear of the chassis facing out of the front of the rack. This flexibility is desirable as some users require access to the front of the chassis, for example, to load/unload storage media, while other users prefer access to the rear of the chassis, for example, to allow connection/disconnection of cables.
[0014] After attachment of the slide brackets to the chassis, the chassis with the slide brackets is mounted onto the mounting shelf. Each slide bracket preferably includes a flange, which together are used to position the chassis on the mounting shelf. The mounting shelf preferably comprises flanges such that when the chassis is properly located on the mounting shelf, the flanges of the slide brackets align with the flanges of the mounting shelf. Fasteners or other forms of connectors can then be used to attach the slide bracket to the mounting shelf. Thus, the invention allows either front-or-rear-orientation equipment mounting and minimizes the costs of mounting by using common parts regardless of orientation.
[0015] [0015]FIG. 1 depicts an arrangement of the inventive rack mount 100 for mounting chassis 103 into rack 101 . The inventive mount 100 includes mounting shelf 102 which supports chassis or device or equipment 103 . Preferably attached to chassis 103 are two slide brackets 104 , with one bracket being mounted on one side, e.g., left, and the other bracket being mounted on the other side, e.g., right. Note that the inventive rack mount 100 preferably does not include rack 101 or chassis 103 .
[0016] Each slide bracket 104 preferably includes a flange 105 that is located on the front distal end of the slide bracket 104 . Flange 105 is used to position the chassis within the rack. As shown in FIG. 1, chassis 103 is being installed into (or removed from) the rack 101 . Flange 105 will stop the insertion of the chassis 103 when flange 105 encounters either rack 101 or mounting shelf 102 . Slide bracket 104 may then be attached to either rack 101 or mounting shelf 102 via connectors such as fasteners, screws, nuts and bolts, pins, adhesives, welds, hooks and slots, keyholes and keyhole standoffs, or any combination thereof.
[0017] Mounting shelf 102 is preferably attached to rack 101 by one or more connectors 204 (FIG. 2) which could comprise one or more pins, screws, nuts and bolts, adhesives, welds, fasteners, hooks and slots, keyholes and keyhole standoffs, or any combination thereof.
[0018] Note that mounting shelf 102 may be sized so as to receive chassis 103 and be able to be attached to rack 101 . Mounting shelf 102 may include adjustable supports or brackets (not shown) so as to attach to rack 101 . This means that the rack 101 does not have to be sized to exactly fit chassis 103 . Thus, rack 101 may be significantly larger than chassis 103 . As shown in FIG. 1, the chassis is mounted into rack 101 so that the front 106 of chassis 103 is accessible at front of rack 101 .
[0019] [0019]FIG. 2 depicts a view similar to that of FIG. 1 except that chassis 103 is not present for easier viewing of the components of the invention. The invention also preferably includes two handles 201 , one of which is mounted on each flange 105 . Handles 201 allow for chassis 103 to be more easily installed into and/or removed from the rack 101 .
[0020] [0020]FIG. 2 also depicts a preferred embodiment wherein shelf 102 includes two flanges 202 , each of which is located so as to contact a respective flange 105 of slide brackets 104 when the chassis 103 is properly located in rack 101 . Flange 105 and flange 202 preferably have co-located holes 203 which enables a connector to securely connect the slide brackets 104 , and hence, chassis 103 , to mounting shelf 102 .
[0021] [0021]FIG. 3 depicts an elevational view of one of the flanges 104 . Each flange 104 would preferably have a chassis mounting system that would allow the chassis 103 to be mounted in either a front orientation or a rear orientation.
[0022] In the embodiment shown in FIG. 3, mounting system 300 preferably comprises hole sets 301 and 302 . Each hole set is specifically configured and placed on flange 104 to enable flange 104 to be attached to a side of chassis 103 . For example, hole set 301 may enable the left side of the chassis to be attached to flange 104 , while hole set 302 enables the right side of chassis 103 to be attached to flange 104 . Thus, flange 104 could be attached to either side of chassis 103 . Note that the mounting system 300 could comprise one or more pins, screws, nuts and bolts, adhesives, welds, fasteners, hooks and slots, keyholes and keyhole standoffs, or any combination thereof.
[0023] Note that the flange shown in FIG. 3 is oriented to attach to the left slide of chassis 103 . The flange would be inverted to be attached to the right side of chassis 103 .
[0024] Note that the holes 203 and hole sets 301 , 302 are shown by way of example only. There could be more holes, fewer holes, holes located in different positions, different-sized holes, or whatever is needed to accommodate attachment of the flange 104 to the mounting shelf 102 or attachment with chassis 103 , respectively. Further note that the connectors 204 are shown by way of example only, as there could be more connectors, fewer connectors, connectors located in different positions, different-sized connectors, or whatever is needed to accommodate attachment of the shelf 102 to rack 101 .
[0025] [0025]FIG. 4 depicts an arrangement of the chassis 103 in the rack 101 such that the rear 401 of chassis 103 is located at the front of rack 101 .
[0026] [0026]FIG. 5 depicts an alternative embodiment 500 of the slide bracket that can be used in arrangements of FIGS. 1, 2 and 4 in place of the slide bracket 104 shown in FIG. 3. Slide bracket 500 includes at least one additional flange, e.g. 501 and/or 502 . The additional flange(s) 501 , 502 increase(s) the strength of the slide bracket 500 . Also, slide bracket 500 may be of sufficient height so that flange 501 interfaces with flange 503 of mounting shelf 102 , and thereby provide easier mounting of the chassis into the rack. Note that bracket 104 may also be of sufficient height so that its upper portion also interfaces with flange 503 .
[0027] [0027]FIG. 6 depicts an alternative embodiment 600 using the slide bracket 500 of FIG. 5. Note that in the embodiments shown in FIGS. 1, 2, and 4 , the slide bracket does not contact the upper flange 503 of the mounting shelf 102 , and the upper portion of chassis 103 may contact the upper flange 503 . Thus, the height of the chassis 103 is limited by the height of the mounting shelf 102 . In the alternative embodiment 600 , the flange 601 of mounting shelf 102 does not contact chassis 103 . The flange 601 preferably contacts the upper flange 501 of each slide bracket 500 . This would prevent vertical movement of the chassis, but would allow the chassis to be of any height. | A system and method for mounting a device into a rack comprises a mounting shelf that is attached to the rack, a first bracket that is attached to a first side of the device, and a second bracket that is attached to a second side of the device, wherein the second side is located opposite to the first side, wherein the first bracket and the second bracket are substantially similar, and wherein the device, with the first bracket and the second bracket attached thereto, is slideably positioned into the mounting shelf and attached to the mounting shelf via the first bracket and the second bracket. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] Embodiments of the invention generally relate to an electrochemical plating cell.
[0003] 2. Description of the Related Art
[0004] Metallization of sub 100 nanometer sized features is a foundational technology for present and future generations of integrated circuit manufacturing processes. However, metallization of sub 100 nanometer features presents several challenges to conventional metallization apparatuses and techniques. For example, conventional metallization techniques for integrated circuit applications generally include depositing a conductive seed layer onto surfaces that are to be metallized, and then electrochemically plating a conductive layer onto the seed layer to metallize and fill the features. The seed layer is often deposited by a physical vapor deposition (PVD) process and generally has a thickness of between about 300 Å and about 700 Å. However, seed layer deposition becomes increasingly difficult with sub 100 nanometer features, as the opening at the top of the features tends to close off from field or horizontal surface deposition before the sidewalls or vertical surfaces of the features are adequately metallized by the seed layer. This closure of the opening of the feature inhibits subsequent processes from metallizing or filling the main body of the feature with the desired conductive material.
[0005] Deposition of the thin seed layer required for sub 100 nanometer features also presents challenges with respect to the continuity or resistance of the thin seed layer. More particularly, since the thickness of the conductive seed layer is directly proportional to the resistance of the layer, the decreasing thicknesses of seed layers in sub 100 nanometer features results in a substantially higher seed layer resistance. This increased resistance is known to cause an edge high plating condition, i.e., thicker plating near the edge of the substrate as a result of the decreased electric field near the center of the substrate from the high seed layer resistance.
[0006] Another challenge in metallization of sub 100 nanometer features is the metallization or feature filling process that is conducted after the seed layer is deposited. Metallization of integrated circuit devices is generally conducted with an electrochemical plating process, however, the small size of the feature opening and high aspect ratio of the feature body makes it very difficult to obtain continuous bottom up fill of the main body of the feature without closing the opening of the feature and preventing subsequent plating in the feature, thus generating an unfilled void or pocket in the feature.
[0007] Therefore, there is a need for an apparatus and method for metallizing sub 100 nanometer integrated circuit devices and minimizing edge high plating effects that result from thin seed layers.
SUMMARY OF THE INVENTION
[0008] Embodiments of the invention provide an electrochemical plating cell configured to metallize sub 100 nanometer features on integrated circuit devices. The plating cell includes a fluid basin having an anolyte solution compartment and a catholyte solution compartment, an ionic membrane positioned between the anolyte solution compartment and the catholyte solution compartment, an anode positioned in the anolyte solution compartment, and a cathode electrode positioned to electrically contact and support a substrate for processing in the fluid basin. The anolyte compartment is divided into a first and second anolyte compartments, such that the anode is positioned in the first compartment and a counter electrode is positioned in the second compartment. The first and second compartments both have an anolyte fluid flow therethrough, however, the first and second compartments are electrically isolated from each other.
[0009] Embodiments of the invention may further provide an electrochemical plating cell having a fluid container having an ionic membrane positioned across the fluid container, the ionic membrane being positioned to fluidly separate a catholyte volume from a first anolyte volume in the fluid container. The plating cell further includes an anode assembly positioned in fluid communication with the first anolyte volume, a cathode substrate support member positioned to support a substrate at least partially in the catholyte volume for a plating process, a counter electrode positioned in fluid communication with a second anolyte volume, the second anolyte volume being electrically isolated from the first anolyte volume, and a vent member positioned in fluid communication with the catholyte volume, the vent member being in ionic communication with the second anolyte volume.
[0010] Embodiments of the invention may further provide a fluid processing cell for depositing a conductive layer onto a substrate. The cell generally includes a catholyte solution fluid volume positioned to receive a substrate for plating, a first anolyte solution fluid volume at least partially ionically separated from the catholyte solution fluid volume, an anode assembly positioned in the first anolyte solution fluid volume, a second anolyte solution fluid volume, the second anolyte solution fluid volume being electrically isolated from the first anode solution fluid volume and at least partially in ionic communication with the cathode solution fluid volume, and a cathode counter electrode positioned in the second anolyte solution volume.
[0011] Embodiments of the invention may further provide an electrochemical plating cell having a fluid basin having an ionic membrane positioned across a middle portion of the basin, the ionic membrane separating the fluid basin into an upper catholyte volume and a lower anolyte volume, an anode assembly positioned in the lower anolyte volume, and a cathode substrate support member removably positioned in the catholyte volume. The plating cell further includes a counter electrode positioned in an isolated anolyte volume, the isolated anolyte volume being positioned below the ionic membrane and not in direct electrical communication with the lower anolyte volume, and a counter electrode vent positioned in an upper portion of the fluid basin at a position proximate an edge of a substrate being plated in the fluid basin, the counter electrode vent being in electrical communication with the counter electrode via a fluid conduit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of 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.
[0013] FIG. 1 illustrates a sectional view of an exemplary electrochemical plating cell and head assembly of the invention.
[0014] FIG. 2A illustrates a schematic sectional view of an exemplary electrode and membrane configuration of the invention.
[0015] FIG. 2B illustrates a horizontal section of the exemplary plating cell showing the anolyte fluid flow patterns.
[0016] FIG. 3 illustrates another sectional view of the plating cell of the invention.
[0017] FIG. 4 illustrates a detailed sectional view of the fluid delivery conduits of the plating cell of the invention.
[0018] FIG. 5 illustrates a detailed sectional view of the fluid return conduits of the plating cell of the invention.
[0019] FIG. 6 illustrates a sectional view of the plating cell of the invention and representative electrical flux lines that are generated during plating operations.
[0020] FIGS. 7 a - 7 e illustrate exemplary anode configurations that may be used in the plating cell of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] The present invention is directed to a plating cell configured to support metallization processes for sub 100 nanometer integrated circuits. The plating cell generally includes a partitioned fluid basin, i.e., the fluid volume in the plating cell fluid basin is separated into a catholyte solution volume and an anolyte solution volume. An example of this type of separation of a plating cell into an anolyte volume and a catholyte volume may be found in commonly assigned U.S. patent application Ser. No. 10/627,336, filed Jul. 24, 2003 entitled “Electrochemical Processing Cell”, which is hereby incorporated by reference in its entirety. The anolyte volume of the plating cell includes at least one anode electrode and at least one counter electrode, however, the counter electrode is positioned and configured to be electrically isolated from the anode electrode.
[0022] FIG. 1 illustrates a simplified sectional view of an exemplary plating cell 100 and head assembly 102 of the invention in a processing position. FIG. 3 illustrates another sectional view of plating cell 100 of the invention without the head assembly 102 . Plating cell 100 includes a head assembly 102 configured to support a substrate for plating operations in a plating cell fluid basin 108 . The head assembly 102 generally includes a thrust plate member 104 and a cathode contact ring member 106 . Thrust plate 104 and contact ring 106 , which will be further discussed herein, are generally configured to support and electrically bias a substrate for electrochemical processing in plating cell 100 . Fluid basin 108 is configured to confine an inner fluid volume 110 and to receive a substrate for plating in the fluid volume 110 . Fluid basin 108 also includes an overflow weir 109 (a contiguous uppermost fluid overflow point) that spills into an outer collection volume 112 that circumscribes weir 109 . Collection volume 112 operates to drain overflow plating solution from the inner volume 110 such that the plating solution may be recirculated back to inner volume 110 . Fluid basin 108 optionally includes a fluid diffusion member 114 positioned across the inner volume 110 at a position below where the substrate 118 being plated is positioned. The fluid diffusion member 114 generally operates to dampen fluid flow variations in the direction of the substrate 118 , as well as operating to provide a resistive element in the plating bath between the anode and the substrate. A more thorough description of the diffusion member and other plating cell components and operational characteristics may be found in commonly assigned U.S. Pat. No. 6,261,433 and commonly assigned U.S. Pat. No. 6,585,876, both of which are hereby incorporated by reference in their entireties.
[0023] Fluid basin 108 further includes a membrane 116 positioned across the fluid basin 108 at a position below where the diffusion member 114 may be positioned, if used. Membrane 116 is generally an ionic membrane, and more particularly, a cationic membrane, that is generally configured to prevent fluid passage therethrough, while allowing ions, such as copper ions, to travel through the membrane 116 toward substrate 118 . As such, membrane 116 generally operates to separate a catholyte volume 119 of the plating cell 100 from an anolyte volume 120 of the plating cell 100 , wherein the catholyte volume 119 is generally defined as the fluid volume between the membrane 116 and the substrate 118 , and the anolyte volume 120 is defined as the fluid volume below the membrane 116 adjacent the anode. A more thorough description of the membrane 116 and the separation of the anolyte from the catholyte may be found in commonly assigned U.S. patent application Ser. No. 10/627,336, filed Jul. 24, 2003 entitled “Electrochemical Processing Cell”, which is hereby incorporated by reference in its entirety.
[0024] The anolyte volume 120 generally contains an anode assembly 122 that includes at least one electrically conductive member positioned in contact with the anolyte solution flowing through the anolyte volume 120 . The conductive member may be manufactured from a soluble material, such as copper, or from an insoluble material, such as platinum or another noble metal, etc. A counter electrode assembly 124 , which is generally positioned radially outward of the perimeter of anode assembly 122 , may also be manufactured from either a soluble or an insoluble material, such as copper, platinum, etc.
[0025] Although anode assembly 122 and the counter electrode 124 are generally positioned such that both assemblies 122 , 124 are in communication with an anolyte solution, the respective assemblies 122 , 124 are also positioned and configured such that the anode assembly 122 is electrically isolated from the counter electrode 124 . More particularly, an electrically insulating spacer 126 is generally positioned between anode assembly 122 and counter electrode 124 . Further, the anolyte solution fluid flow that is in fluid contact with the anode assembly 122 is not the same anolyte fluid flow that is in fluid contact with the counter electrode 124 , as will be further discussed herein with respect to FIG. 4 . Anode assembly 122 is in electrical communication with an anodic terminal of a power supply (not shown). The cathodic terminal of the same power supply is generally in electrical communication with the contact ring 106 , which is configured to electrically contact the substrate 118 and the counter electrode 124 . However, although only one power supply is discussed herein with respect to supplying the cathodic bias, it is understood that more than one independently controlled power supply may be used without departing from the scope of the invention.
[0026] A plating solution, also termed a catholyte, is supplied to the catholyte volume 119 by a fluid supply conduits 133 a , 133 b which is in fluid communication with a catholyte solution tank (not shown). The catholyte solution generally includes several constituents, including, for example, water, copper sulfate, halide ions, and one or more of a plurality plating additives (levelers, suppressors, accelerators, etc.). The catholyte solution supplied by conduits 133 a , 133 b overflows the weir 109 and is collected by collection volume 112 . The anolyte solution is supplied to anolyte volume 120 by an anolyte supply conduit 131 a and drained from anolyte volume 120 by an anolyte drain conduit 131 b positioned on an opposing side from the supply conduit 131 a . The positioning of the supply and drain conduits 131 a , 131 b generates directional flow of the anolyte across the upper surface of the anode 122 , as described in commonly assigned U.S. patent application Ser. No. 10/268,284, filed Oct. 9, 2002 entitled “Electrochemical Processing Cell”, which is hereby incorporated by reference in its entirety.
[0027] Plating cell 100 also includes a second anolyte fluid inlet 132 a and a second anolyte fluid drain 132 b . The second anolyte fluid inlet 132 a is configured to supply an anolyte solution to the volume 135 surrounding the counter electrode 124 , while not fluidly or electrically communicating with the main anolyte volume 120 contained in the volume adjacent the anode 122 and supplied by conduits 131 a , 131 b as illustrated in FIG. 2 a . Volume 135 is fluidly bound by membrane 116 on the upper side thereof. The fluid boundary is generally a result of the lack of fluid permeability of membrane 116 , combined with positioning two seals 136 adjacent electrode 124 , and more particularly, between the partition 126 and membrane 116 , and between the cell body portion 127 outward of electrode 124 and membrane 116 . The positioning of the two seals 136 , which may generally be circular o-ring-type seals, operates to channel the flow of anolyte supplied by conduit 132 a around volume 135 to drain conduit 132 b . As such, the anolyte supplied by conduit 132 a generally flows through the volume 135 above the counter electrode 124 in a semicircular pattern, as illustrated by arrows “A” in FIG. 2 b . As such, the anolyte fluid circulated through the volume 135 is collected by the second anolyte drain conduit 132 b on the opposing side of the cell from which the anolyte was supplied by conduit 131 a . Alternatively, the anolyte supplied to the anolyte compartment 120 generally flows directly across the anode 122 , as illustrated by arrows “B” in FIG. 2 b , and is collected by conduit 131 b . The fluid flows indicated by arrows “A” and “B” both occur below the membrane 116 . Flow “A” occurs between seals 136 , and flow “B” occurs across the top of the anode 122 radially inward of the inner seal 136 .
[0028] Although the membrane 116 provides a fluid barrier that prevents the anolyte solution from fluidly transferring therethrough, membrane 116 allows for ionic transfer, and more particularly, for positive ionic transfer. As such, although the anolyte cannot permeate membrane 116 , ions such as copper and hydrogen ions may transfer through the membrane 116 into vent conduit 140 , which contains catholyte. Thus, the combination of the volume 135 above the electrode 124 and the catholyte in vent conduit 140 generates an electrical path for current to travel from the cathode contact ring (the substrate) 106 to the counter electrode 124 .
[0029] FIG. 2 a illustrates the flux lines generated near the anode 122 and the counter electrode 124 during a plating process. The electrical flux immediately above the anode 122 is represented by the arrows labeled “C”. The flux above the anode 122 may be controlled by applying a different electrical power to the respective anode segments 122 a , 122 b , and 122 c . Anode segments 122 a , 122 b , 122 c may be concentric, symmetric, or any other configuration depending upon the desired flux. FIGS. 7 a - 7 e illustrate exemplary anode configurations that may be used in embodiments of the invention, wherein the anode segments 1 , 2 , and 3 are denoted. It is understood that each of segments 1 , 2 , and 3 of the respective anode arrangements may be individually powered to control and/or optimize plating parameters. Returning to FIG. 2 a , the anode segments 122 a , 122 b , 122 c may also be individually powered and are not limited to any particular number, i.e., there may be between 1 and about 10 or more anode segments in a plating cell. With regard to independently powering anode segments, anode segment 122 a illustrated in FIG. 2 a has more power applied thereto than anode segment 122 b . This is evident from the density of the flux lines “C” originating from segment 122 a is greater than those originating from anode segment 122 b , thus indicating the less power is being applied to segment 122 b.
[0030] FIG. 4 illustrates an enlarged sectional view of the electrode and membrane configuration of the plating cell of FIGS. 1 and 3 on the fluid supply side of the plating cell. More particularly, arrows “F” indicate the anolyte fluid flow path for the anolyte solution that is flowing over the upper surface of anode 122 . The anolyte fluid flow indicated by arrows “F” is generally supplied to conduit 131 a and directed to flow across the upper surface of anode 122 in the flow direction generally indicated by arrows “B” in FIG. 2 b . This fluid flow is generally perpendicular to any slots or elongated apertures formed into anode 122 for the purpose of receiving anode sludge or other dense fluids that may form on the anode surface during plating operations.
[0031] Arrows “G” in FIG. 4 indicate the anolyte ion flow path for the anolyte solution that is flowing over the counter electrode 124 , which also generally corresponds with the fluid flow indicated by arrows “A” in FIG. 2 b . As such, the anolyte ion flow “G” is generally supplied to volume 135 by conduit 132 a , which generates a semicircular flow of fluid over the top of the counter electrode 124 , below membrane 116 , and between seals 136 .
[0032] Arrows “E” indicate the fluid flow path for the catholyte solution that is supplied to the catholyte volume 119 of plating cell 100 . The catholyte solution flows upward through conduit 132 a , then generally horizontally across at least a portion of the upper surface of membrane 116 , and then upward to an opening, i.e., vent conduit 140 , that communicates with the catholyte region 119 . The flow of the catholyte over the upper surface of the membrane is generally configured to be at a position that overlaps the volume 135 above the counter electrode 124 , which provides a current path between the catholyte and the counter electrode 124 via transmission through membrane 116 . This current path generally travels from the cathode contact ring 106 through vent 140 via the catholyte solution residing therein, through membrane 116 , and through the anolyte residing in volume 135 to the counter electrode 124 , as indicated by arrows “H” in FIG. 6 .
[0033] FIG. 5 illustrates an enlarged sectional view of the electrode and membrane configuration of the plating cell of FIGS. 1 and 3 on the fluid drain side of the plating cell. Arrows “J” illustrate the flow direction for the anolyte being removed from the anode chamber 120 adjacent the anode 122 . The anolyte drain conduit 131 b is positioned to drain anolyte from the anode chamber 120 in a direction that is generally perpendicular to slots formed in the anode 122 , as illustrated by arrows “B” in FIG. 2 b . Arrows “K” illustrate the flow direction of the anolyte solution over the counter electrode 124 . The anolyte flowing over counter electrode 124 is removed from the volume 135 above the electrode 124 at a point that facilitates the semicircular flow pattern illustrated by arrows “A” in FIG. 2 b . Arrows “L” illustrate the catholyte flow direction for the catholyte traveling through supply conduits 131 a , 131 b to supply fresh catholyte to the catholyte chamber 119 . Arrows “M” illustrate the flow direction of the anolyte being drained from volume 135 above the counter electrode 124 .
[0034] In operation, counter electrode 124 is used in combination with anode member 122 , which may be one of the segmented anodes illustrated in FIGS. 7 a - 7 e or variations thereof, to control the electrical flux across the surface of the substrate 118 being plated. More particularly, counter electrode 124 , which is also in electrical communication with a power supply (not shown) is used to selectively reduce the electric flux near the edge of the substrate 118 to prevent edge high plating. Counter electrode 124 reduces the electric flux near the edge of the substrate by supplying an additional cathodic flux source to the area proximate the edge or perimeter of the substrate 118 . Counter electrode 124 supplies the additional flux, which is illustrated by arrows “H” in FIG. 6 , to the area proximate the edge or perimeter of the substrate by electrically communicating with the cathode volume 119 via vent 140 . Vent 140 , which is generally an annular vent that circumscribes the perimeter of the substrate, is positioned to conduct flux from the counter electrode 124 to the catholyte volume 119 in a manner that reduces the quantity of flux generated by the substrate/cathode near the perimeter of the substrate. More particularly, the combination of vent 140 and counter electrode 124 being cathodically biased essentially operates to flood the perimeter of the substrate with a flux source, which prevents the anode from conducting flux directly to the perimeter edge of the substrate where vent 140 is supplying flux. As such, the electrical flux originating on the substrate 118 is increased near the center of the substrate 118 , as illustrated by arrows “C” in FIG. 6 , while reducing the electrical flux at the substrate surface near the perimeter of the substrate 118 , as the flux represented by arrows “H” has essentially displaced the flux originating near the perimeter of the substrate 118 .
[0035] This reduction in the flux near the perimeter of the substrate, which may be controlled by the cathodic bias applied to the counter electrode 124 , generally operates to reduce edge or perimeter high plating characteristics of conventional plating cells. More particularly, the counter electrode 124 operates as a cathodic source near the edge of the substrate 118 via the flux traveling from counter electrode 124 through vent 140 to the anode assembly 122 , and therefore, reduces the flux near the edge of the substrate. This reduced flux has been shown to reduce the plating near the perimeter of the substrate.
[0036] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, wherein the scope is determined by the claims that follow. | A fluid processing cell for depositing a conductive layer onto a substrate is provided. The cell includes a catholyte solution fluid volume positioned to receive a substrate for plating, a first anolyte solution fluid volume at least partially ionically separated from the catholyte solution fluid volume, an anode assembly positioned in the first anolyte solution fluid volume, a second anolyte solution fluid volume, the second anolyte solution fluid volume being electrically isolated from the first anode solution fluid volume and at least partially in ionic communication with the cathode solution fluid volume, and a cathode counter electrode positioned in the second anolyte solution volume. | 2 |
FIELD OF THE INVENTION
[0001] The present invention is related to computer software and mare specifically to computer software for financial analysis of closed ended private fund investments.
BACKGROUND OF THE INVENTION
[0002] “Fund”, as used herein and throughout this description, refers to closed ended private fund investments. Examples of a Fund include but are not limited to private equity, private closed ended Funds of Funds, buy-out, venture capital, real estate, natural resources, and energy Funds that are not openly marketed to the general public and are generally subject to substantial restrictions on transferability. A Fund, in its singular form, refers to a single Fund, or a group of related Funds that have the same strategy and are managed by the same manager.
[0003] 1. Technical Field
[0004] This disclosure generally relates to a financial field combined with social networking, and more specifically relates to rating Funds through communication of information between potential buyers on a social network website.
[0005] 2. Background Art
[0006] Social media has become an important mean of communication in our modern world. Already a large amount of people have accounts with various social media applications including Facebook, Twitter, and LinkedIn allowing them to post messages and communicate to a large number of people. The social media now allows the user to create groups and communicate with other users on specific interests and express interest in specific products.
BRIEF SUMMARY OF THE INVENTION
[0007] This social media mechanism described in this method allows potential buyers and managers of Funds to communicate and exchange information regarding specific Funds. The method allows scoring the liquidity of each specific closed ended private Fund through analysis of the information gathered through the social media mechanism and information obtained through conventional means including, but not limited to, disclosure by the Fund manager, institutional buyers, and agents and information available in the public domain.
[0008] “Fund”, as used herein and throughout this description, refers to closed ended private fund investments. Examples of a Fund include but are not limited to private equity, private closed ended Funds of Funds, buy-out, venture capital, real estate, natural resources, and energy Funds that are not openly marketed to the general public and are generally subject to substantial restrictions on transferability. A Fund, in its singular form, refers to a single Fund, or a group of related Funds that have the same strategy and are managed by the same manager.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 shows a simplified view of the initial set up required for the method
[0010] FIG. 2 shows a simplified view of the system
[0011] FIG. 3 shows a flowchart of the method
DETAILED DESCRIPTION OF THE INVENTION
[0012] “Fund”, as used herein and throughout this description, refers to closed ended private fund investments. Examples of a Fund include but are not limited to private equity, private closed ended Funds of Funds, buy-out, venture capital, real estate, natural resources, and energy Funds that are not openly marketed to the general public and are generally subject to substantial restrictions on transferability. A Fund, in its singular form, refers to a single Fund, or a group of related Funds that have the same strategy and are managed by the same manager.
[0013] The claims and disclosure herein provide a new method that utilizes a social media mechanism and online communication over the internet to collect data and information from users over the internet, analyses it with other available data and information, and generates liquidity ratings for Funds. The preferred initial hardware embodiment required and its functionality is shown in FIG. 1 . The system comprises a computer-readable medium ( 8 ) in a server ( 6 ), connected ( 4 ) to the internet ( 2 ), which in turn is connected either with wires or remotely to a plurality of remote terminals ( 1 ) of financial data providers who have uploaded financial information ( 3 ). A specially designed program ( 9 ), comprising computer readable statements and instructions, is stored in the computer readable medium ( 8 ), written in a language such as Java, Python, ASP, Sal or any other computer programming language and is capable, when run by a processor ( 7 ), of sorting and intelligently filtering data (including semantics methods) ( 5 ) provided by users via social media mechanism, Fund managers, institutional investors, financial data providers, and financial intermediaries and reorganizing into a new database ( 10 ) that can be stored in the computer readable medium. The database ( 10 ) can be updated from time to time by accessing updated data ( 5 ) using internet ( 2 ) and internet connection ( 4 ).
[0014] The functionality of the method within hardware embodiment and hardware itself are shown in FIG. 2 . The system comprises a computer-readable medium ( 20 ) in a server ( 11 ), connected ( 4 ) to the internet ( 2 ), which in turn is connected either with wires or remotely to a plurality of remote terminals ( 14 ). A specially designed software application containing the social media mechanism ( 21 ), comprising computer readable statements and instructions, is stored in the computer readable medium ( 20 ), written in a language such as Java, Python, ASP, Sal or any other computer programming language and is capable, when run by a processor ( 22 ), of processing information ( 15 ) provided by remote terminals ( 14 ) over the internet ( 2 ) and of processing information from the database ( 10 ) that has been created in the initial stage. The program is configured to display information on a remote terminal ( 14 ) including information from the database such as current Fund information ( 17 ), Funds liquidity rating and ranking ( 19 ), and input parameters used to select the particular Fund ( 16 ). The system is designed to receive information from multiple users and terminals ( 14 , 14 a, and 14 b ).
[0015] The functionality of the preferred embodiment of the system is shown in FIG. 3 . First, the database should be created by the specially designed program in the server as described in FIG. 1 . Next, the user of the system would connect to the server that can process information from database as described in FIG. 2 . The users would provide Fund information, express their interest in specific Funds, and the users purchasing abilities using forms or wizards, including forms and wizards on social media mechanism, that will, in turn, be collected by the server and processed by the software application. The Fund data and users' interest in the Fund along with legal and financial capability of the users to invest into the Fund would be analyzed ( 23 ) by the software application and then the software application would assign and set the initial liquidity score for each Fund. The software application then would analyze each Fund ( 24 ), using information from the database ( 10 ), as to the restrictions in place for each specific Fund and comparing it against the ability of the interested users to invest in such Fund. The software application then would adjust and assign an adjusted liquidity score for each Fund. The software application then would analyze the potential size of trades for each specific Fund, and also analyse and compare the ability of users to conduct trades based on the potential size of transactions ( 25 ). The software application then would adjust and assign a new adjusted liquidity score for each Fund. The application software would analyse ( 26 ) the adjusted liquidity score for each Fund and assign a specific liquidity rating ( 27 ) based on the final liquidity score, ending the process.
[0016] The process may be extended further by allowing the software application to save the liquidity ratings and scores to the database ( 10 ). The method may allow the software application to rank Funds based on their liquidity ratings and create a Fund ranking. The method may further allow the software application to generate reports to the user, including liquidity rating reports for multiple Funds and rate the liquidity of a portfolio of Funds.
[0017] One skilled in the art will appreciate that many variations are possible within the scope of the claims. Thus, while the disclosure is particularly shown and described above, it will be understood by those skilled in the art that these and other changes in form and details may be made therein without departing from the spirit and scope of the claims. | Closed ended private investment Funds may require liquidity rating as those Funds are not readily traded on any exchange or alternative trading system, but traded on limited access market. A new social media mechanism allows assigning liquidity rating to closed ended private investment funds based on potential institutional buyers interest, potential institutional buyers' capacity and Funds' restrictions. | 6 |
BACKGROUND OF THE INVENTION
Technical Field
The present invention relates generally to multi-port medical devices. More particularly, the invention relates to a medical manifold having rotatable ports.
Background Information
During the course of a medical or surgical treatment, a patient may be incapable of adequately breathing on his/her own. In order to ensure that a sufficient supply of oxygen is provided to the patient, the physician may initiate a period of artificial ventilation. Artificial ventilation is typically carried out by inserting an endotracheal tube into the trachea of the patient via the mouth or nose, a process referred to as intubation. A mechanical ventilator supplies oxygen through the endotracheal tube (ETT) to the patient's lungs.
During management of such patients, it may be desirable to coaxially insert one or more catheters, etc., into the patient's trachea through the ETT. Such devices may be positioned to carry out a medical procedure, or as a diagnostic tool. Examples of medical procedures include placement of a balloon-tipped catheter (e.g., an endobronchial blocker) for lung isolation, as well as other procedures such as jet ventilation, etc. Examples of diagnostic procedures include monitoring of bodily temperature, pressure, gas composition, etc. In such cases, the distal end of the catheter typically extends beyond the distal end of the ETT, and in many instances, is inserted into either the right or left mainstem bronchus. To ensure adequate placement, the position of the catheter is generally viewed through the endotracheal tube with an elongated viewing instrument, such as a fiberoptic bronchoscope.
A multi-port manifold may be engaged with the proximal end of the ETT to allow for simultaneous placement through the ETT of a plurality of different medical devices. Examples of such devices include a catheter (such as the endobronchial blocker catheter described above), various diagnostic tools, a bronchoscope, and a wire guide. Additionally, the manifold provides a conduit for ventilation of the patient. In some manifolds, each of these features is carried out through a separate port.
A distal port of the manifold is connected to the ETT. Another port is generally positioned in-line with the distal port, and with the lumen of the ETT. When introducing a bronchoscope into the airway, the bronchoscope is inserted through the in-line port, and extended through the distal port to ensure suitable visualization into the trachea. In some applications, a wire guide is inserted through a working channel of the bronchoscope, and directed into the desired right or left mainstem bronchus under visualization through the bronchoscope.
Once the wire guide is positioned in the desired region, the bronchoscope is removed from the in-line port. The catheter (e.g., an endobronchial blocker) is inserted over the wire guide in the in-line port, and advanced in the direction of the desired mainstem bronchus. The bronchoscope is then inserted through a side (angled) port to visualize the advancement of the catheter, and to verify that the catheter has entered the proper mainstem bronchus. Difficulties may be encountered when advancing a bronchoscope through a side port. A bronchoscope is typically a delicate instrument which has the ability to be tip deflected from the proximal end. However, the tip deflecting ability of such instruments can be impaired if the proximal end of the scope is at an acute angle with respect to the distal tip. In addition, when the bronchoscope is inserted through an angled port, the optics are generally not as suitable when compared to entry and advancement through an in-line port. In addition to the bronchoscope, other delicate and/or fragile instruments may be subject to impairment or damage if inserted through an angled port.
It would be desirable to overcome the problems encountered in the art by providing a manifold having multiple entry ports, wherein such ports are rotatable such that more than one port can be selectively axially aligned with the lumen of the ETT. It would further be desirable to provide rotatable entry ports wherein each port is arranged on the manifold in a manner such that each said port maintains access to the target site, to allow simultaneous passage of a respective medical device through each of said ports.
BRIEF SUMMARY
The present invention addresses the shortcomings of the prior art. In one form thereof, the invention comprises an airway manifold having a manifold body comprising an upper body portion and a lower body portion. The body portions are engaged such that the upper body portion is rotatable relative to the lower body portion, whereby a generally hollow interior space is defined thereby. The lower body portion has a port open to the interior space, and the upper body portion includes a plurality of ports open to the interior space. A first upper body port is axially alignable with the lower body port to define a substantially linear passageway therebetween when the upper body portion is at a first rotatable position relative to the lower body portion. A second upper body port is axially alignable with the lower body port to define a substantially linear passageway therebetween when the upper body portion is at a second rotatable position relative to the lower body portion.
In another form thereof, the invention comprises an airway system, wherein a manifold comprises an upper body and a lower body. The upper body and the lower body are engaged such that the upper body is rotatable relative to the lower body, and a generally hollow interior space is defined thereby. The lower body includes a first port and a second port, wherein each of the lower body ports is open to the interior space. The upper body includes a first port and a second port, wherein each of the upper body ports is open to the interior space. The upper body first port is axially alignable with the lower body first port to define a substantially linear passageway therebetween when the upper body is at a first rotatable position relative to the lower body. The upper body second port is axially alignable with the lower body first port to define a substantially linear passageway therebetween when the upper body is at a second rotatable position relative to the lower body. An airway tube is engaged with the lower body first port. A ventilator is engaged with the lower body second port. A viewing device is insertable through the upper body first port and the lower body first port when the upper body is at the first rotatable position relative to the lower body, and insertable through the upper body second port and the lower body first port when the upper body is at the second rotatable position relative to the lower body. A guide device is insertable through one of the first and second upper body ports and extendable therefrom through the airway tube.
In still another form, the invention comprises a method of introducing a medical device into a mainstem bronchus of a patient. A manifold is positioned at a proximal end of an airway tube. The manifold comprises an upper body and a lower body engaged such that the upper body is rotatable relative to the lower body, and such that a generally hollow interior space is defined thereby. The lower body includes a first port and a second port, each of which opens to the interior space. The upper body includes a first port and a second port, each of which opens to the interior space. The upper body first port is axially alignable with the lower body first port to define a substantially linear passageway therebetween when the upper body is at a first rotatable position relative to the lower body. The upper body second port is axially alignable with the lower body first port to define a substantially linear passageway therebetween when the upper body is at a second rotatable position relative to the lower body. The airway tube proximal end is positioned at the lower body first port, and the airway tube distal end extends into the trachea of the patient. The respective distal ends of a viewing device and a guide device are introduced through the upper body first port when the upper body is at the first rotatable position relative to the lower body, and the distal ends are advanced through the lower body first port and airway tube, and into the trachea. The distal ends are advanced toward a target mainstem bronchus, and the guide device distal end is advanced into the target bronchus under visualization from the viewing device. The viewing device is withdrawn through the upper body first port, and a position of the guide device is maintained along the first port and the target bronchus. The upper body is rotated to the second rotatable position relative to the lower body. The viewing device distal end is introduced through the upper body second port, and advanced through the lower body first port and airway tube toward the target mainstem bronchus. The distal end of the medical device is introduced through the upper body first port, and advanced toward the target bronchus. The medical device may comprise an endobronchial blocking device having an inflatable balloon at a distal end thereof, and the viewing device may comprise a bronchoscope.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a prior art multi-port manifold;
FIG. 2 is a perspective view of a manifold having rotational ports according to an embodiment of the present invention;
FIG. 3 is a longitudinal sectional view of the manifold shown in FIG. 2 ;
FIG. 4 is another perspective view of the manifold of FIG. 2 , after a rotation of the upper body ports of the manifold;
FIG. 5 is a view of the upper body portion of the manifold;
FIG. 6 is a view of the lower body portion of the manifold;
FIG. 7 is a view of the manifold connected to an endotracheal tube, wherein a first upper body port is axially in-line with a lower body port, and a bronchoscope extends through the axially aligned ports;
FIG. 8 is a view of the manifold connected to an endotracheal tube as in FIG. 7 , wherein the bronchoscope has been withdrawn and the upper body ports have been rotated such that a second upper body port is axially in-line with the lower body port;
FIG. 9 is a view as in FIG. 8 , wherein the bronchoscope has been inserted through the second upper body port, and an endobronchial blocking device has been inserted through the first upper body port;
FIG. 10 is a view as in FIG. 9 , wherein the balloon of the blocking device has been inflated in a target bronchus; and
FIG. 11 is a view of an alternative embodiment wherein the manifold has three upper body ports.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
For purposes of promoting an understanding of the present invention, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It should nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
In the following discussion, the terms “proximal” and “distal” will be used to describe the opposing axial ends of the manifold, as well as the axial ends of various component features. The term “proximal” is used in its conventional sense to refer to the end of the manifold (or component) that is closest to the operator during use of the manifold. The term “distal” is used in its conventional sense to refer to the end of the manifold (or component) that is initially inserted into the patient, or that is closest to the patient during use.
FIG. 1 depicts an airway manifold 100 of a type known in the art. Manifold 100 includes a plurality of ports open to the interior of the manifold. A mechanical ventilation port 102 is configured for connection to a mechanical ventilator (not shown). An endotracheal tube connection port 104 is configured for connection to the proximal end of the endotracheal tube (not shown). A bronchoscope port 106 having an end cap 107 is positioned opposite to, and in-line with, the endotracheal tube connection port 104 . An auxiliary port 108 is positioned at an angle with reference to the bronchoscope port. The auxiliary port may be configured to receive a wire guide, a catheter, or other treatment or diagnostic device. One example of a prior art manifold as shown in FIG. 1 is described in U.S. Pat. No. 6,086,529, incorporated by reference herein.
FIG. 2 is a perspective view of a manifold 10 according to an embodiment of the present invention. FIG. 3 is a longitudinal sectional view of the manifold of FIG. 2 . As described herein, and as further shown in FIGS. 5 and 6 , manifold 10 comprises an upper, or proximal portion 12 ( FIG. 5 ), and a lower, or distal portion 30 ( FIG. 6 ). Upper and lower portions 12 , 30 are engaged to form manifold 10 , and are configured to permit relative rotation between upper portion 12 and lower portion 30 . In the non-limiting embodiment described in greater detail herein, manifold portions 12 , 30 are rotatably engaged via a snap fit.
Upper portion 12 comprises an annular ledge 14 , and includes ports 20 , 24 extending in a proximal direction from ledge 14 . As shown in FIG. 3 , annular ledge 14 includes an internal slot 16 formed circumferentially therearound. Ports 20 , 24 comprise respective generally tubular body members, and are spaced at an angle of, e.g., about 30-60 degrees relative to each other.
In the preferred embodiment shown, ports 20 , 24 have a proximal end provided with external threads 22 , 26 , respectively. Respective end caps 21 , 25 are sized and aligned for threaded connection with the external threads of ports 20 , 24 via corresponding internal threads (not shown). An opening 23 , 27 extends through each of the end caps and communicates with the hollow interior of manifold 10 . In a preferred embodiment, a conventional valve member, such as check-flow valve 29 ( FIG. 3 ) or a Tuohy valve, is provided internally of end cap 21 , 25 in well-known fashion to establish a fluid-tight connection with a device extending through respective opening 23 , 27 .
Lower portion 30 includes a ring-like tab 32 at its upper, or proximal, end. In the embodiment shown, tab 32 is sized and configured to be received in internal slot 16 by conventional means, such as a snap fit. Tab 32 is dimensioned relative to slot 16 in a manner to inhibit disengagement of the respective upper and lower manifold portions 12 , 30 during normal usage, but to permit relative rotation therebetween. Those skilled in the art will appreciate that other means for engagement of the respective upper and lower portions 12 , 30 may be substituted, as long as such alternative means is structured to provide secure engagement between the respective upper and lower portions, while at the same time permitting relative rotation therebetween as described herein.
As shown, e.g., in FIGS. 4 and 6 , lower portion 30 comprises a generally elongated body 34 . Elongated body 34 preferably tapers from the proximal end to at least a side port 40 that extends at an angle from elongated body 34 . Port 40 may extend at an angle of about 90 degrees from body 34 as shown. Those skilled in the art will appreciate that although this angle is preferred, other angles, such as angles between about 30 and 60 degrees, may be substituted for the angle shown, as long as the position of port 40 does not functionally interfere with the remaining ports, as described herein. Port 40 may be configured to include a conventional 15 mm ventilator fitting portion 41 for connection to a mating fitting of a ventilation apparatus. Although port 40 is shown herein as having a fitting portion configured for engagement to a conventional 15 mm ventilator, this is not required. As a further alternative, port 40 may be configured for engagement with connectors of other configurations, for example, as a luer lock fitting for engagement with a corresponding connector of a jet ventilation device.
A distal port 36 is provided at the distal end of elongated body 34 . Distal port 36 is configured for engagement with, e.g., a proximal end of an airway tube, such as an endotracheal tube or other breathing tube capable of supplying a ventilating fluid to the patient. In one embodiment, distal port 36 may be provided with external threads 38 that are sized and aligned for threaded connection with corresponding internal threads (not shown) of a connector 37 . Connector 37 may be sized and configured for engagement in conventional manner with a proximal end of the endotracheal tube.
Upper and lower manifold portions 12 , 30 are preferably formed of a generally rigid polymeric composition, such as a polycarbonate, polyamide (nylon), polyethylene, propylene, or other thermoplastic composition. Upper and lower portions 12 , 30 may be formed and shaped by conventional processes, e.g., injection molding, insert molding, or conventional machining techniques. Those skilled in the art will appreciate that the compositions and forming techniques described herein are only intended to represent non-limiting examples, and that other known compositions and techniques may be suitable for a particular application.
An example illustrating the use of manifold 10 will now be provided. This example describes the use of manifold 10 for introducing an endobronchial blocker into a mainstem bronchus of a patient, in this case, into the right mainstem bronchus. Those skilled in the art will appreciate that this example is not intended to be limiting in any manner. Thus, the manifold may likewise be utilized for the introduction of other medical and diagnostic devices, and for introducing such devices at other target sites in the body of the patient.
As described above, it is generally desirable to insert a device, such as a bronchoscope 200 , through a proximal port of the manifold that is axially in-line with the distal port 36 , and with the lumen of an endotracheal tube 220 that extends in a distal direction from distal port 36 . This arrangement is shown in FIG. 7 , wherein proximal port 20 is axially in-line with distal port 36 and endotracheal tube 220 . Endotracheal tube 220 extends into the trachea 230 of the patient, in well-known manner. Only the distal portion of trachea 230 that branches into the right and left mainstem bronchus 240 , 245 , respectively, is shown in FIGS. 7-10 . A ventilator 90 is schematically shown functionally engaged with port 40 in FIGS. 7-10 . Ventilators, e.g., mechanical ventilators, jet ventilators, etc., are well known in the art, and those skilled in the art can readily select an appropriate ventilator for use herein. The remaining body portions of the patient are not shown, as they are not necessary for understanding the example described herein.
Upon insertion of bronchoscope 200 into port 20 as described, the distal end 202 of the bronchoscope extends beyond distal end 222 of the endotracheal tube, and is directed in a conventional manner to approach the selected right 240 or left 245 mainstem bronchus. In this example, the bronchoscope distal end 202 is deflected toward right mainstem bronchus 240 in well-known fashion, e.g., utilizing conventional articulating features of the bronchoscope.
A guide device, such as wire guide 210 , is also inserted into port 20 . Preferably, wire guide 210 is inserted via a lumen extending through bronchoscope 200 . Under visualization provided by the bronchoscope, the distal end of wire guide 210 is advanced into right mainstem bronchus 240 , as shown in FIG. 7 . As described herein, it is desirable to obtain wire guide access to the selected bronchus, and to maintain such wire guide access during the period of time in which the medical device, e.g., the endobronchial blocker, is introduced and positioned in the selected mainstem bronchus. In addition, it is generally desirable to maintain wire guide access for a period of time thereafter, until it is confirmed that proper access has been achieved and that the device is functioning in a desired manner. By maintaining wire guide access to the target site, rapid reinsertion of a misplaced or non-functioning device, or rapid insertion of a replacement device, can be achieved if deemed necessary by the physician without the necessity to re-establish wire guide access to the target site, in this case, the right mainstem bronchus. Although referred to herein as a wire guide, those skilled in the art will appreciate that in some instances other thin-walled flexible devices, e.g., a thin-walled catheter or cannula, capable of carrying out the function of a wire guide as described herein may be substituted for a conventional wire guide.
Once it is confirmed that the wire guide has accessed the right mainstem bronchus, the bronchoscope may be withdrawn over the wire guide, leaving the wire guide in place. At this time, the proximal ports 20 , 24 of the upper manifold portion 12 may be rotated to a second position, as shown in FIG. 8 . Following rotation of the ports, port 24 is now in-line with distal port 36 and the lumen of endotracheal tube 220 . Although wire guide 210 and port 20 are no longer in-line with the distal port 36 , the wire guide continues to extend beyond the distal port and secure access into the mainstem bronchus 240 .
At this time, bronchoscope 200 may be inserted into newly-aligned port 24 such that bronchoscope distal end 202 once again extends beyond distal end 222 of the endotracheal tube, and is directed toward right mainstem bronchus 240 as before. A medical device, such as endobronchial blocker 236 , may be inserted into port 20 over wire guide 210 . Endobronchial blocker 236 includes a blocker balloon 237 at its distal end.
Endobronchial blocker 236 is advanced in the right mainstem bronchus under visualization provided by the bronchoscope until the balloon is determined to be in a suitable location for inflation. If desired, blocker 236 can be provided with a distal loop 238 as described, e.g., in U.S. Pat. Nos. 5,904,648 and 7,578,295, both incorporated by reference herein. In this example, the distal loop receives the bronchoscope, so that as the bronchoscope advances into the right mainstem bronchus, the blocker may be advanced along with the bronchoscope. This is shown in FIG. 9 .
Once the distal end of the endobronchial blocker enters the bronchus, the bronchoscope may be partially withdrawn, e.g., approximately to the entry position of the bronchus or proximal of the entry point. The blocker may then be advanced to the desired position in the bronchus, under continued visualization by the bronchoscope. Once the balloon is deemed to be in a favorable position in the bronchus, the balloon is inflated, as shown in FIG. 10 . Further discussion of the positioning of an endobronchial blocker in a desired mainstem bronchus is provided in the incorporated-by-reference patents.
Maintaining bronchoscopic visualization upon inflation of the balloon enables the physician to confirm proper placement, and inflation, of the balloon prior to removing the bronchoscope. Maintaining wire guide access to the target site enables the physician to quickly initiate remedial measures, such as replacement of the blocker, if deemed necessary, e.g., due to dislodgement or puncture of the balloon, etc. The rotatable features of the manifold enable the bronchoscope to be initially introduced, and re-introduced, through a port of the manifold that is axially in-line with the distal port, as described above.
FIG. 11 illustrates an alternate embodiment of a rotational manifold 70 . Manifold lower portion 30 may be formed to have the same configuration as the lower portion in the preceding embodiment, and similar reference numbers are utilized to describe the features of the lower portion. In this embodiment, upper portion 72 has three upper ports 76 , 80 , 84 extending from annular ridge 74 . Each of upper ports 76 , 80 , 84 may include a respective end cap 77 , 81 , 85 , and may be provided with external threads 78 , 82 , 86 , as described in the previous embodiment. Ports 76 , 80 , 84 may include respective openings 79 , 83 , 87 extending through each of the end caps.
In this embodiment, each of ports 76 , 80 , 84 communicates with the hollow interior of manifold 70 . Upper manifold portion 72 is rotatable in the manner of upper manifold portion 12 , such that a selected one of ports 76 , 80 , 84 may be axially in-line with port 36 at any particular time. As with the previous embodiments, a valve member (not shown) may be provided internally of the respective end cap to establish a fluid-tight connection. Those skilled in the art will appreciate that the presence of an additional port provides the opportunity to introduce additional devices, etc., to the target site without losing the access to that site provided by the wire guide.
It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention. | An airway manifold includes a manifold body having an upper body portion and a lower body portion. The body portions are engaged such that the upper body portion is rotatable relative to the lower body portion, whereby a generally hollow interior space is defined. The lower body portion has a port open to the interior space, and the upper body portion includes a plurality of ports open to the interior space. A first upper body port is axially alignable with the lower body port to define a substantially linear passageway therebetween when the upper body portion is at a first rotatable position relative to the lower body portion. A second upper body port is axially alignable with the lower body port to define a substantially linear passageway therebetween when the upper body portion is at a second rotatable position. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a new and improved construction of automatically engageable synchronous jaw clutch with hydraulic engagement-servo device.
With a state-of-the-art synchronous jaw clutch, as taught in German Pat. No. 1,181,992, and the corresponding U.S. Pat. No. 3,154,181 a respective toothed drive and power take-off clutch half and a clutch star are provided, the clutch star being guided to be axially displaceable by means of a first gear-tooth system upon one of the toothed clutch halves and can be engaged, by means of a second gear-tooth system, with the other clutch half. A screw socket controls, during clutching or engagement, the clutch star. This screw socket is in meshing engagement, by means of a pair of coarse-pitch thread means with one of the clutch halves and can be coupled, by means of a pawl blocking device, with the other clutch half. The engagement-servo device of the jaw clutch contains a piston which entrains the clutch star, and the displacement of the piston, initiated by the screw socket, controls an infeed channel leading to a servo cylinder chamber or compartment of the servo device, in order to hydraulically augment the engagement of the clutch. The screw socket is mounted to be axially non-displaceable in the clutch star and the piston is secured to a piston rod which, together with a head portion formed at its one end, likewise is mounted to be axially non-displaceable in the clutch star. The channel controlled by the piston extends through a fixed bushing in which there is guided the end portion of the piston rod which faces away from the head portion. This end portion has an annular groove at a spacing from the piston, this annular groove being continuously connected by bores with the cylinder compartment or chamber and, when the clutch is disengaged, does not flow communicate with the line controlled by the piston.
With this heretofore known clutch the clutching or engaging operation begins when the drive body, which is connected with a driving unit or machine, overtakes the power take-off body which is connected with a machine which should be driven. The overtaking phenomenon means that the clutch star temporarily leads, in relation to the screw socket, in the drive rotational direction, with the result that the pawl blocking device latches or engages, so that the screw socket is entrained in the drive rotational direction by the clutch star. Consequently, the screw socket carries out a relative rotation in relation to the power take-off body and the pair of coarse-pitch thread means insures that the screw socket carries out a screwing or threading motion towards the power take-off body. Since there is not possible any relative displacement of the screw socket in relation to the clutch star, the screw socket immediately entrains the clutch star in axial direction, whereby its second gear-tooth system begins to engage in the tooth gaps of the gear-tooth system of the power take-off body. In order to facilitate such both gear-tooth systems must be provided with helical portions. When such gear-tooth systems come into engagement with one another at a predetermined length, then the piston, which has been shifted in axial direction by the clutch star, reaches a position in which the channel controlled thereby is connected with the cylinder compartment. From this point on pressurized fluid medium flows without hinderance into the cylinder compartment and the pressure prevailing thereat displaces the piston and together therewith the clutch star further into the clutching or engagement direction, until the second gear-tooth system of the clutch star is completely coupled with the related gear-tooth system of the power take-off body.
The described known clutch has been found to be highly satisfactory even when working with large torques. However, if the clutch should be capable of transmitting extremely large rotational moments or torques, and thus, the clutch star must be dimensioned to be of a corresponding large size, then the moment of inertia of the clutch star can be so large that during a first phase of the engagement or clutching operation an appreciable torque must be transmitted by means of the clutch, in order to shift the clutch star in axial direction to such an extent until, during a second phase of the clutching or engagement operation, the axial force exerted by the pressurized fluid medium upon the piston and from such upon the clutch star, enables the clutch to completely engage. However, the rotational movement or torque required during the first phase, for instance when starting-up turbine-generator units, is not always available. On the other hand, the danger exists that the clutch star, at the end of the clutching operation, attains its end or terminal position, defined by stops, with too greater an axial velocity. Hence, owing to the large moment of inertia of the clutch star and the parts which are moved along their width, it is possible for damage to arise at the clutch itself and equally at the bearings of the shafts which are coupled by such clutch. With the heretofore known clutch it is possible to permit the piston, during the engagement operation, to displace the pressurized fluid medium into a second cylinder chamber or compartment, from where such pressurized fluid medium can outflow by means of a throttle location. However, it is difficult to regulate the throttling action such that it does not additionally render more difficult the incipient stage of the clutching or engagement operation of the clutch.
SUMMARY OF THE INVENTION
Therefore, with the foregoing in mind it is a primary object of the present invention to provide a new and improved construction of jaw clutch which is not afflicted with the aforementioned drawbacks and limitations of the prior art clutch discussed above.
Another and more specific object of the present invention aims at providing a self-synchronizing clutch which even then, if it is designed for transmitting large rotational moments or torques, only requires a minimum torque for the entire clutching operation, even for the first phase thereof.
A further noteworthy object of the present invention is to provide a new and improved construction of automatically engageable synchronous jaw clutch with hydraulic engagement-servo device, which is relatively simple in design and to manufacture, extremely reliable in operation, not readily prone to breakdown or malfunction, and requires a minimum of maintenance and servicing.
Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the synchronous jaw clutch with hydraulic engagement-servo device of the present invention is manifested by the features that, the engagement device is structured as a servo follow-up control wherein the piston as a follow-up piston, when hydraulically loaded or impinged, follows a sliding displacement of the leading screw socket which is axialy movable to a limited degree relative to the clutch star and to the piston and opens and closes the infeed channel to the servo cylinder chamber or compartment by means of a control groove provided at the piston.
By means of the invention there is achieved the beneficial result that, the torque transmitted by means of the pawl blocking device need only be so large that there is formed an axial force at the pair of coarse-pitch thread means, which is just large enough to alone axially displace the screw socket, whereas the clutch star and together therewith the piston initially remains stationary. The screw socket therefore leads the piston, and consequently, prior to the time that the clutch star has begun its axial movement, the pressurized fluid medium frees the path in the cylinder compartment, so that right from the start the force, exerted by the pressurized fluid medium upon the piston and via such upon the clutch star, axially shifts the clutch star in the clutching or engagement direction. This axial shifting or displacement however is accomplished in a controlled manner, since the inflow of the pressurized fluid medium to the cylinder compartment is automatically throttled or, in fact, completely interrupted when the piston leaves the screw socket.
According to a further feature of the invention a partial section or portion of the infeed channel extends through an axial extension or projection of the screw socket upon which there is guided the follow-up piston constructed as an annular or ring piston.
A further feature of the invention contemplates that the follow-up piston is displaceable, in the declutching or disengagement direction, relative to the clutch star.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a perspective cutaway view of a synchronous jaw clutch depicted in its disengaged or declutched state;
FIGS. 2a to 2e respectively show axial sectional views of the synchronization device of the synchronous jaw clutch of the arrangement of FIG. 1, and specifically;
FIG. 2a illustrates the clutch arrangement in its disengaged or declutched state;
FIG. 2b illustrates the clutch arrangement in a position ready for engagement or clutching;
FIG. 2c illustrates the clutch arrangement during synchronization;
FIG. 2d illustrates the clutch arrangement at the end of synchronization;
FIG. 2e illustrates the clutch arrangement in the engaged state;
FIG. 3a illustrates an enlarged detail sectional showing of the arrangement of FIG. 2a; and
FIG. 3b illustrates a corresponding detailed sectional showing of the arrangement of FIG. 2e.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, the exemplary illustrated synchronous jaw clutch will be seen to comprise a drive clutch or coupling half 12 which is fixedly connected with a drive machine or unit, for instance typically a gas turbine by way of example and not limitation, and a power take-off clutch or coupling half 14. The latter is arranged at a determined axial spacing from the drive clutch half 12, and this power take-off clutch half 14 is fixedly connected with a driven machine or unit, for instance typically a generator, again by way of example and not limitation. Further, the synchronous jaw clutch comprises a clutch star 16 arranged to be axially displaceable between the drive clutch half 12 and the power take-off clutch half 14. This clutch star 16 or equivalent structure has a straight gear-tooth system or straight gear teeth 18 which continuously mesh with a complementary internal gear-tooth system 20 of the drive clutch half 12. Additionally, the clutch star 16 is further provided with a second straight, helical external gear-tooth system or teeth 22. The external gear-tooth system or gear teeth 22, by axially displacing the clutch star 16, can be brought into engagement with a straight, helical internal gear-tooth system or teeth 24 of the power take-off clutch half 14. The clutch star 16 is connected, by means of a displacement or shift ring 26 and a rod 28 or equivalent structure, with a hydraulic control device or control means 30.
With the clutch disengaged, as best seen by referring to FIGS. 1, 2a and 3a, the clutch star 16 is supported and centered, on the one hand, by the gear-teeth systems or gear teeth 18 and 20 and, on the other hand, by a support tube 32 which is secured coaxially upon the drive clutch half 12. The support tube 32 possesses, for this purpose, a centering collar 34 which coacts with a portion 36 of reduced diameter of an axial bore of the clutch star 16 so long as the jaw clutch is not engaged. When the clutch is engaged the clutch star 16 is supported and centered, on the one hand, by the gear teeth systems or gear teeth 18 and 20 and, on the other hand, by the gear teeth 22 and 24, whereas there is then eliminated the supporting action at the centering collar 34, as best seen by referring to FIGS. 2e and 3b.
Internally of the power take-off clutch half 14 there are formed recesses or depressions 38 or equivalent structure, in which there is arranged a respective pawl 40 which bears by means of a pivot or tilt edge 42, formed at its outer surface, at the wall of such related recess 38. Operatively associated with the pawls 40 is an axially displaceable or shiftable screw socket 44 having a pawl gear-tooth system or ratchet 46 formed at the outer circumference thereof. The not particularly referenced teeth of the pawl gear-tooth system or ratchet 46 have a smaller or larger angular rotational spacing than the recesses 38 and, accordingly, the pawls. The product of the number of pawls 40 and the number of teeth of the ratchet 46 is equal to the number of teeth of the gear teeth or gear-tooth systems 20 and 22. Consequently, the gear teeth 20 and 22 always then can be engaged when one of the pawls 40 engages behind a tooth of the ratchet 46.
Each pawl has operatively associated therewith a pressure or compression spring 48 or equivalent structure, which is supported at the power take-off clutch half 14 in approximately radial direction. Each such compression spring 48 strives to press the related pawl 40 so as to engage or mesh with the ratchet or pawl gear-tooth system 46. The mass of each pawl 40, in relation to the tilt edge 42, is distributed in such a manner that, the pawls, under the action of the centrifugal forces which arise in the presence of high rotational speeds of the power take-off clutch half 14, strive to overcome the forces of the compression springs 48, to lift-off from the ratchet 46 and thus to avoid any further contact with the screw socket 44 or equivalent structure.
Formed internally of the screw socket 44 is a coarse-pitch threading or thread means 50 engaging with complementary external coarse-pitch threading or thread means 52 of a disk or plate 54 or equivalent structure. The disk 54 is fixedly connected, by means of a support shaft 56 with the support tube 32, and by means of the latter with the drive clutch half 12. The screw socket 44, which thus is centered by means of the coarse-pitch threading or thread means 50 and 52 in relation to the support tube 32, on the other hand possesses a tubular-shaped axial projection or extension 58. This axial projection or extension 58 is guided to be axially displaceable at the support tube 32 and limits therewith a substantially ring-shaped or annular servo cylinder compartment or chamber 60. A substantially ring-shaped or annular follow-up piston 62 is guided to be axially displaceable upon the axial projection or extension 58. This follow-up piston 62 protrudes, by means of its one end, into the servo cylinder compartment 60. At its other end such follow-up piston 62 carries a collar 64 engaging into an annular or ring-shaped groove 66 of the tube-shaped projection 58. The ring-shaped groove 66 is wider than the collar 64, so that it enables and limits axial movements of the follow-up piston 62.
The clutch star 16, the support tube 32 and the axial projection 58 of the screw collar 44 possess infeed channels or ducts 68, through which there is infed oil for any possible axial position of the screw socket 44. The infed oil is delivered by a lubrication system through the displacement ring 26 of the clutch star 16 to an external, substantially ring-shaped control groove 70 of the projection 58. The external control groove 70 has operatively associated therewith an internal control groove 72 which is machined at the follow-up piston 62. The internal control groove 72 is flow connected by channels or ducts 74 in the follow-up piston 62 with the servo cylinder compartment or chamber 60.
Continuing, it will be observed the follow-up piston 62 has an outer collar 76 with which there is operatively associated an inner shoulder 78 of an entrainment sleeve or bushing 80 secured at the clutch star 16, so that the follow-up piston 62 can axially entrain, in the clutching direction, the clutch star 16.
In the description to follow there will now be described the mode of operation of the clutch, there being assumed that the driving machine, and thus also the drive clutch half 12, initially is at standstill and the clutch is disengaged, with the gear teeth 22 and 24 therefore being out of engagement with one another. This condition has been shown in FIGS. 1, 2a and 3a. The hydraulic control device 30 exerts such a force upon the displacement ring 26--this force being directed towards the left of the showing of the drawings--that the clutch star 16 is retained in the disengaged or declutched position. Hence, the shoulder 78 of the entrainment sleeve 80 attached at the clutch star, presses the collar 76 of the follow-up piston 62 against the neighboring end surface of face of the support tube 32. The follow-up piston 62 thus retains, by means of its collar 64, the screw socket 44 fixed in axial direction. The pressurized fluid medium, here assumed to be oil under pressure, arriving by means of the displacement ring 26, the channels 68, the control grooves 70 and 72 and the infeed channels 74 in the servo cylinder compartment or chamber 60, exerts a force upon the follow-up piston 62 which, while opposing the retention force of the control device 30, is nonetheless considerably smaller so that the clutch remains in the disengaged state shown in FIGS. 1, 2a and 3a. Now it is assumed that the machine which is fixedly connected with the power take-off clutch half 14, and thus also the power take-off clutch half itself, already rotate at the normal operating rotational speed. The co-rotating pawls 40 are raised from the ratchet or pawl gear-tooth system 46, since the centrifugal force acting upon the pawls 40 is significantly greater than the force of the compression springs 48. Hence, there does not prevail any frictional contact between the stationary and the revolving components of the clutch.
Now if the drive machine should be coupled with the driven machine, then, on the one hand, the rotational speed of the driven machine is reduced, and, on the other hand, the drive machine is rotated at a relatively small rotational speed amounting to, for instance, 100 revolutions per minute. If the drive machine is assumed, for instance, to constitute a gas turbine, then such rotation typically occurs through the use of an auxiliary drive. The control device 30 is activated, for instance by a standard electromagnetic valve, although other switching devices can be employed, such that the holding force exerted by means of the displacement ring 26 upon the clutch star 16 in the declutching direction, is reduced, and consequently, becomes smaller than the hydraulic force which is effective at the follow-up piston 62 in the clutching direction. The oil pressure prevailing in the servo cylinder compartment or chamber 60 now displaces the follow-up piston 62 in the direction of the power take-off clutch half 14. The follow-up piston 62, together with its collar 76, is pressed against the shoulder 78 of the entrainment sleeve 80 and by means of such entrains the entire clutch star 16. This movement is transmitted, by the displacement ring 26 and the rod 28, to the control device 30.
Initially, the screw socket 44 does not participate in the aforedescribed displacement of the follow-up piston 62, because the collar 64 of the follow-up piston 62 has axial play in the ring or annular groove 66 of the tubular-shaped projection or extension 58. Therefore, the follow-up piston 62 initially is only displaced to such an extent in the clutching or engaging direction, until the control groove 70 no longer overlaps with the control groove 72, so that the oil infeed to the servo cylinder compartment 60 is interrupted. An equilibrium condition is established between the force of the control device 30, effective in the disengaging or declutching direction and the force of the follow-up piston 62, effective in the clutching or engagement direction. Hence, as shown in FIG. 2b, the clutch is now in its preparatory position.
If the machine, which should be driven by means of the synchronous jaw clutch, further slows down, then there is ultimately attained a rotational speed at which the force of the compression springs 48 overcomes the centrifugal force effective at the pawls 40 and pushes such pawls 40 against the ratchet 46, until finally one of the pawls 40 latches behind a tooth of the ratchet or pawl gear-tooth system 46. If the rotational speed of the machine which is to be driven drops further, then it finally falls below that of the drive machine. Consequently, the disk 54, attached at the support shaft 56, overtakes the screw socket 44, which, in turn, is hindered by the latched pawl 40 in overtaking the power take-off coupling half 14. Therefore, there prevails at the course-pitch threading or thread means 50 and 51 an axial force, effective in the clutching or engagement direction, which displaces the screw socket 44 in the direction of the power take-off clutch half 14, and specifically, relative thereto purely axially, but relative to the disk 54, and thus also to the drive clutch half 12 and to the clutch star 16, in a helical or screw motion corresponding to the pitch of the coarse-pitch threading 50 and 52. Owing to the axial movement of the screw socket 44 together with the projection or extension 58, while initially the follow-up piston 62 is still at standstill, the control grooves 70 and 72 again overlap one another, i.e., are in flow communication with one another, so that further oil can flow into the servo cylinder compartment 60, as this has been shown specifically in FIG. 2c. As a result, the follow-up piston 62 again is shifted in the clutching or engagement direction, until the oil inflow to the servo cylinder compartment 60 has again been interrupted, as the same has been illustrated in FIG. 2d.
In the preceding discussion, as a matter of simplicity, there has been considered to be negligible the throttle action prevailing between the edges of the control grooves 70 and 72. In reality, this throttle action has the result that the follow-up piston 62 does not move stepwise, rather continuously, and thus, the clutch star 16 continuously readjusts the screw socket 44. In this phase of the engagement operation the screw socket 44 need only fulfill a control function. The force for displacing the clutch star 16 is applied by the oil in the servo cylinder compartment 60, and thus there are generated large axial displacement forces, without the pawls 40 and pawl gear-tooth system or ratchet 46 being loaded with any appreciable torque or rotational moment.
The described displacement of the clutch star results in its outer or external gear-tooth system 22 threading into the internal gear-tooth system 24 of the power take-off clutch half 14, with a helical or screw motion, the pitch of which corresponds to that of the coarse-pitch threading 50 and 52.
As soon as there has been attained a certain axial overlapping of the teeth systems 22 and 24, then the previously mentioned, but not illustrated conventional electromagnetic valve is switched, with the result that there is reversed the direction of the mechanical force exerted by the hydraulic control device 30 through the intermediary of the rod 28 of the displacement ring 26 upon the clutch star 16. Consequently, this clutch star 16 is further accelerated in the engagement or clutching direction, until the gear-tooth systems 22 and 24 are completely engaged, as shown in FIG. 2e. The scew socket 44, during this last phase of the engagement or clutching motion, does not have any function and also does not participate in the further axial movement of the clutch star 16. Therefore, the shoulder 78 of the entrainment sleeve 80 is distanced from the collar 76 of the follow-up piston 62.
Now the drive machine is run-up to speed, and thus, the clutch can be loaded with its full operating torque, since the screw socket 44 only loosely co-rotates and the pawls 40 are no longer loaded. Hence, the pawls 40 can disengage or lift-off from the ratchet 46, as soon as there has been reached the rotational speed at which the centrifugal forces acting upon the pawls 40 are greater than the forces of the compression springs 48.
The disengagement of the synchronous jaw clutch can be triggered at any random rotational speed in conventional manner in that, the aforementioned electromagnetic valve has infed thereto a switching signal, and thus, pressurized oil is conducted to the disengaging side of the control device 30 and at the same time there is load relieved the engaging or clutching side thereof. As a consequence, the control device 30 displaces the clutch star 16 towards the drive clutch half 12, by means of the rod 28 and the displacement ring 26, so that the gear-tooth systems 22 and 24 come out of meshing engagement. The follow-up piston 62 is displaced back into its starting position, shown in FIGS. 1 and 2a, by the entrainment sleeve 80, the shoulder 78 of which presses against the collar 76, and in this starting position the follow-up piston 62 entrains by means of its collar 64 also the screw socket 44.
While there are shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims. Accordingly, | An automatically engageable synchronous jaw clutch with hydraulic engagement-servo device, comprising a respective toothed drive and power take-off clutch half and a clutch star, which is guided to be axially displaceable by means of a first gear-tooth system upon one of the toothed clutch halves and can be engaged, by means of a second gear-tooth system, with the other clutch half. A screw socket controls, during clutching or engagement, the clutch star. This screw socket is in meshing engagement, by means of a pair of coarse-pitch thread means with one of the clutch halves and can be coupled, by means of a pawl blocking device with the other clutch half. The engagement-servo device contains a piston which entrains the clutch star, and the displacement of the piston, initiated by the screw socket, controls an infeed channel leading to a servo cylinder chamber of the servo device, in order to hydraulically augment the engagement of the clutch. The engagement device is structured as a servo follow-up control wherein the piston as a follow-up piston, when hydraulically loaded or impinged, follows a sliding displacement of the leading screw socket which is axially movable to a limited degree relative to the clutch star and to the piston and opens and closes the infeed channel to the servo cylinder chamber by means of a control groove provided at the piston. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to apparatus for placing a uniform, predetermined charge onto a member having an insulating layer.
2. Description of the Prior Art
Although the corona-charging apparatus of the present invention has general applications, one preferred application is in the field of electrophotographic apparatus (herein called copiers). In copier corona-charging apparatus, a generally uniform electrostatic charge is deposited on a segment of an imaging member having a photoconductive insulating layer. The charged segment is then advanced to an exposure station where it is exposed to image-forming radiation to form a latent electrostatic image of a document to be copied. The latent image is thereafter developed and subsequently transferred to paper upon which the copied image is to appear.
Consistent, high quality reproduction can best be obtained when a uniform level of charge is applied to the imaging member by the corona-charging apparatus. The contrast value of the electrostatic latent image is related directly to the level of charge on the imaging member before exposure. If the photoconductor is not uniformly charged over the entire area, the contrast value of the latent image obtained upon exposure will vary in different areas of the imaging member, and a mottled effect will be visible on the image when developed.
The current from a corona-emitting electrode is a function of the electrode diameter and the potential applied thereto. Variations in the potential will cause relatively large changes in corona current with corresponding variations in the charging rate. The corona current is also affected by deposits of dust that may accumulate on the electrode and by variations of movement and ionized conditions of the air surrounding the electrode. Thus, minute differences in electrode diameter, slight accumulations of dust on the electrode, and variations in air current or in air pressure drastically affect the corona generating potential of the electrode, causing non-uniform electrostatic charging of the imaging member.
Conventional corona-charging apparatus employ an AC power supply coupled to the corona-emitting electrode through a series of rectifiers to obtain a high DC potential at the electrode. The need for high voltage components to rectify the AC supply current and to properly handle the total current demands of the system greatly add to the expense of the apparatus.
The need for rectification of an AC supply current applied to the corona-emitting electrode has been eliminated in known charging apparatus by locating a control electrode (known as a grid), to which has been applied a potential approximately equal to that to which the photoconductor is to be charged, between the corona-emitting electrode and the imaging member. A DC voltage is impressed upon the grid to regulate the flow of ions from the AC supplied corona-emitting electrode to the imaging member. Although this system produces a uniform charge without the need for rectifying the AC supply current, the system does so at the expense of more components, including a DC power supply for the grid.
In certain known corona-charging apparatus, such as disclosed in commonly-assigned U.S. Pat. No. 3,370,212 which issued on Feb. 20, 1968 to L. F. Frank, the need for a DC power supply for the grid has been eliminated by connecting the grid to reference potential through a rectifier and resistor. Even though there is no active power supply for the grid, there is a control voltage imposed at the grid, which voltage results from the current passing through the resistor.
While the level of charge placed on the imaging member by the Frank apparatus can be regulated to some extent by, for example, the relative movement of the corona-emitting electrode and the imaging member, such control methods are imprecise and involve complicated drive mechanisms. I have intended corona-charging apparatus for applying a potential to the insulating layer of an imaging member using only passive grid control elements in the grid circuit, wherein the applied potential is easily regulated and is extremely uniform.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a corona-charging apparatus for charging an insulating layer, wherein a grid acts to stabilize the corona current without the need of an active power supply to the grid and wherein the grid current is controlled in response to the sensed charge placed on the insulating layer. Such apparatus, when compared to corona-charging apparatus known in the prior art, is inexpensive, noncomplex, reliable, and compact.
The foregoing, as well as other objects and advantages, are accomplished by providing a corona-charging apparatus including a conductive control grid, at least one corona-emitting electrode, and means for providing a current supply to the electrode. Current is sinked from the grid through a variable impedance, and means are provided for sensing the voltage produced on the insulating surface to be charged.
In a preferred embodiment of the present invention, the electrode power supply is AC, and the grid current sink includes a rectifier circuit. Means, responsive to the sensed voltage adjust the conductivity of the variable impedance in accordance with a predetermined program to thereby maintain the charge on the surface substantially constant.
BRIEF DESCRIPTION OF THE DRAWINGS
In the detailed description of the preferred embodiments of the invention presented below, reference is made to the accompanying drawings in which:
FIG. 1 is a side elevational view in schematic form of a portion of electrophotographic apparatus in accordance with the invention;
FIG. 2 is an enlarged cross-section of an imaging member for the apparatus shown in FIG. 1;
FIG. 3 is a schematic of a portion of the apparatus shown in FIG. 1 that is directed to the depositing of a generally uniform charge upon an imaging member; and
FIG. 4 is a schematic diagram of a controller for use with the apparatus of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The corona-charging apparatus of the present invention has general applications, but will be described herein in a form particularly useful in electrophotographic apparatus (i.e., copiers). Because such apparatus is well known, the present description will be directed in particular to elements forming part of or cooperating more directly with the present invention.
With reference to FIG. 1, a web-type copier 10 includes an imaging member 12 mounted for movement in the direction of arrow 13 about an endless path, past various operative stations. As can be seen more clearly in FIG. 2, imaging member 12 includes a photoconductive insulating layer 14 (e.g., of the type disclosed in U.S. Pat. No. 3,615,414) overlying a thin, electrically-conductive layer 16 both supported on a film 18. The conductive layer is electrically connected to ground or other reference potential source by edge contact with rollers of the apparatus or by other techniques known in the art.
Operative stations of copier 10 include a charging station at which corona-charging apparatus 20 applies an overall primary charge to the external surface of photoconductive insulating layer 14. After receiving the primary charge, an image segment of imaging member 12 advances past an exposure station 22 where the segment is imagewise exposed to image-forming radiation. The resultant latent electrostatic image then residing on the segment is next advanced over a magnetic brush development station 24 where toner is attracted to the charge pattern corresponding to dark image areas of the document. The developed image is than advanced to a transfer station 26 where the toner image is transferred by corona discharge device 28 to paper, fed from supply 30.
The image segment from which the toner is transferred advances past a cleaning station 32 in preparation for another copy cycle. Erase illumination source 34 can be located after the cleaning station to dissipate residual charge prior to initiating another copy-making sequence of the image segment.
FIG. 3 illustrates details of a preferred embodiment of corona-charging apparatus of FIG. 1. A high voltage AC power supply 36 is connected to a corona-emitting electrode 38. Electrode 38 is enclosed in a grounded shield 40. Below shield 40 is a segment of an imaging member 12, such as illustrated in FIG. 2, which is to be charged.
A conductive grid 42 is positioned between corona-emitting electrode 38 and photoconductor 12. The grid is connected to ground through a pair of diodes 44 and 46 and their respective RC circuits 48 and 50. Each RC circuit includes a variable impedance such as adjustable resistors 52 and 54, and a capacitor 56 and 58. The capacitors are used for smoothing and stability, and may be considered to be optional.
OPERATION OF THE PREFERRED EMBODIMENT
Assuming that a positive charge is to be placed on imaging member 12, resistor 54 is adjusted to a small value; effectively a short circuit. During the positive half cycle of AC power supply, current flows from corona-emitting electrode both to grid 42 and to imaging member 12; the division of current being a function of the relative voltages of the grid and the imaging member. Grid current flows through diode 44 and adjustable resistor 48. Accordingly, the grid voltage and the aforementioned division of current are direct functions of the resistivity of the adjustable resistor.
During the negative half cycle of AC power supply, diode 46 maintains grid 42 at reference or ground potential, resistor 54 being shorted. As such, there is no charge flow to imaging member 12. If desired, resistor 50 could be adjusted to cause a slight charge flow to the imaging member. For placing a negative charge on the imaging member, the relative values of resistors 52 and 54 can be reversed.
The value of adjustable resistors 52 and 54 are regulated by a controller 60 and an electrometer 62. The electrometer is conventional and may include a scanning probe which is translated across imaging member 12 in a transverse direction for averaging purposes.
Controller 60 is responsive to the output of electrometer 12 to regulate the values of the resistors. FIG. 4 illustrates one embodiment of a controller, suitable for effecting a desired adjustment to resistors 52 and 54, although other controllers will readily occur to those skilled in the art.
A set of parallel differential comparators 64-68 compare reference voltages at the inverting input with the output of electrometer 62. When the electrometer voltage exceeds the reference voltage for a given comparator, a "high" signal is generated at the output of the comparator. The reference voltage for each comparator is set by a voltage divider network including variable resistors 69-75. Each differential comparator is associated with a respective light emitting diode (LED) 76 which is activated when the comparator generates a "high" signal. In turn, each LED causes one photoconductor cell 78 to conduct when the associated LED is active. A conducting photoconductive cell shorts out a portion 80-84 of variable resistor 52, removing that portion of the resistor from the total, and decreasing the value of resistor 52.
When only a small voltage is sensed on imaging member 12, none or only a few differential comparators are "high" starting from the bottom comparator in FIG. 4. Thus, all or most of photoconductive cells 78 are non-conductive to maximize the value of resistor 52 and thereby increase the voltage at grid 42. As the imaging member voltage increases, more LED's 76 are activated until a desired voltage is reached.
Resistor portions 80-84 may be equal to each other, or for non-linear control, may be of different values to optimize control about a presumed optimum value. Controller 60 has been rendered adjustable by allowing for adjustment of variable resistors 69-74. Thus, the imaging member voltage at which each individual comparator 64-68 goes "high" can be fine tuned to accommodate various machine parameters.
The present invention includes a feedback control of the grid voltage using measurements of potential on the imaging member, and it is highly desirable that that control be adjustable. However, the controller illustrated and described herein is exemplary, and programmable controller designs will readily occur to those skilled in the art.
For example, signals from the electrometer relating to imaging member potential may be digitized and fed to a computer which can calculate or provide through a look-up table in memory a desired grid potential. The output from the computer can illuminate the respective LED's 76 or render conductive suitable gate-actuatable rectifiers comprising the equivalent of photoconductors 78.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. | A corona-charging apparatus includes a conductive control grid, at least one corona-emitting electrode, and means for providing a current supply to the electrode. Current is sinked from the grid through a variable resistance, and means are provided for sensing the voltage produced on the insulating surface to be charged.
The electrode power supply is AC, and the grid current sink includes a rectifier circuit. Means, responsive to the sensed voltage adjust the conductivity of the variable resistance in accordance with a predetermined program to thereby maintain the charge on the surface substantially constant. | 6 |
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