Abstract:
Methods and apparatus for translating angular velocity and rotary motive force of an input drive to angular velocity and rotary motive force of an output drive, by providing a pair of devices rotatable at, relative to or about a common axis, and translating means for transmitting angular velocity and rotary motive force of a first of the devices to angular velocity and rotary motive force of a second of the devices. In a preferred embodiment, the translating means includes a variably and controlledly groundable reaction disk for varying the throughput from the input to the output. A generator captures energy spent on the rotating reaction disk.

Description:
This application is a continuation-in-part of U.S. patent application Ser. No. 670,263, filed Mar. 14, 1991, entitled: SPEED CONVERTER, now U.S. Pat. No. 5,312,306 and a continuation-in-part of U.S. patent application Ser. No. 08/076,010, filed Jun. 11, 1993, entitled: HIGH EFFICIENCY VARIABLE OUTPUT SPEED CONVERTER now abandoned, and PCT Patent Application Serial No. PCT/US92/02023, filed Mar. 13, 1992, entitled: SPEED CONVERTER, incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to mechanical power transmissions, and more particularly, to speed reducers and the like for use between a drive and driven shaft. 
     Speed conversion is an important capability in the efficient utilization of rotary motive force. The occasion often arises for reducing the speed of a drive member to a lower speed and higher torque at a driven member. In automobiles, for example, a hydraulic transmission, with various combinations of gear assemblies, accomplishes the task of translating the high rotary speed of the gasoline engine to the lower rotational requirements at the driven axle. Typically, such transmissions are quite complex, requiring many parts to operate in sophisticated syncopation, and are quite labor intensive for both assembly and service. 
     It is therefore an object of the present invention to provide a speed converter which is simplified in nature, highly efficient, and is robust in transmission capability. 
     It is yet another object of the present invention to provide speed converter which requires few moving pans and having high operational and volumetric efficiency. 
     It is a further object of the present invention to provide a transmission which is relatively easy to assemble and service. 
     It is yet an additional object of the present invention to provide optimized load sharing among the multi-elements that transmit the rotary motive force in a speed converter. 
     It is yet another object of the present invention to provide a high efficiency seamlessly shifting, variable speed converter for use as a vehicular transmission in a vehicle driven by an electric motor or by an internal combustion engine and operating at variable or constant speed. 
     SUMMARY OF THE INVENTION 
     In one illustrative embodiment, a motor vehicle transmission comprises a pair of cam devices rotatable about a common axis cooperating via translating means. This translating means transmits angular velocity and rotary motive force of a first of the devices (i.e., input) to angular velocity and rotary motive force of a second of the devices (i.e., output). The translating means includes a reaction disk having at least one slot (radial or axial depending upon the embodiment) for oscillation of an interacting element in the slot, the reaction disk being located with the conjugate pair about the common axis, wherein the interacting element couples the first device to the second device. As a result, the angular velocity and rotary motive force of the first device (input) is efficiently translated by the translating means into the angular velocity and rotary motive force of the second device (output). 
     In a preferred embodiment of the invention, the speed converter comprises, firstly, an input disk mounted on an input shaft, wherein the disk has a face that extends radially perpendicular to the shaft. This face contains a grooved cam track forming a drive cam track. The drive cam track, in simplest form, has one cycle starting at a base circle radius and proceeding rotatably about the center of the disk and shaft at a constantly increasing radius and at a constant angular rotation to a maximum radius at 180°, i.e., in the rise mode, and then proceeding rotatably in the fall mode at a decreasing radius of the same rate and constant angular rotation as in the rise mode back to the original base circle radius, completing 360° of rotation. 
     Next, the speed converter comprises an output disk mounted on an output shaft, wherein the disk has a face that extends radially perpendicular to the shaft. This face has a grooved cam track for forming a driven cam track, and which is mounted along the shaft in a position facing the face cam track of the drive cam. This driven face cam contains a plurality of rise and fall modes that are selected to achieve a desired speed conversion, which in this case is in ratio with the single cycle of the drive cam. Each rise and fall mode of the plurality of cycles in the driven cam are configured to have the same radial displacement, for uniform conversion. 
     In this preferred embodiment, the speed converter includes a reaction disk having a plurality of slots for respective receipt of respective transmission elements (i.e., balls), all within a common housing. The invention produces constant velocity for 360 degrees rotation at the output, with torque transmission through each of the transmission elements for 360 degrees of rotation at the output. All of the transmission elements share the load continuously, thereby decreasing the unit load on each transmission element. 
     In a speed reverser embodiment of the invention, the drive cam, reaction disk and driven cam are still required, although with variation of the cam curvature and ball geometry. Thus it is possible to interchange a reverse motion drive cam for the drive cam of the above speed reducer. 
     In a particular embodiment of the invention, a seamlessly-shifting variable-speed transmission is taught in which the reaction disk acts as a splitter/modulation device. The reaction disk has an outer circumference configured with a coupling arrangement, such as gear teeth. A corresponding coupling, such as a gear, is provided on the shaft of a controller device coupled to the outer circumference of the reaction disk. When the controller device is at a stand still, it grounds the reaction disk and all torque throughput is taken out at the speed reducer output. As the controller device permits rotation of the reaction disk it varies the degree of grounding of the reaction disk and as a result splits off some of the speed reducer input via the reaction disk, the speed converter output being reduced accordingly. Thus as the reaction disk rotation is modulated, the effective speed converter output modulates accordingly. 
     In a further embodiment, a seamlessly-shifting wide range transmission is provided having a primary drive loop and a high speed loop. Computer (e.g., a microcomputer or microprocessor) controlled controllers vary the degree of grounding of the associated reaction disks for accommodation of higher and lower torque demands. These demands reflect momentary conditions and changes thereof, such as acceleration, deceleration, and coasting. 
     One embodiment of this system preferably is provided with an energy recapture function. In this recapture function, a capture device, such as a &#34;generator&#34; (e.g., a generator, alternator, compressor, pump, or the like), captures and harnesses the energy outputted via the reaction disk and uses or stores it accordingly. The generator output thus can be stored for later use, so as to obtain optimal operating efficiency. This optimization comes from the fact that the generator is operated with otherwise lost energy, and only as optimally delivered under computer control. 
     This computer-regulated system enables running the conventional auxiliary power systems, such as for electrical power, braking and power steering, using rotary energy available at the reaction disks. This energy can be increased or decreased as such load requires. Hence recaptured energy at the reaction disk is stored or used efficiently, and can be increased or decreased as needed. This will yield optimal fuel efficiency. 
     The present cam invention provides a highly efficient replacement for gear type transmissions. In the prior art gear assemblies, as the commonplace gears turn, they interact with each other by their teeth, essentially one tooth at a time. As these teeth engage, frictional losses occur as the tooth surfaces rub and slide against each other. Also, driving with single teeth puts all of the effort and stress on those single teeth, and these teeth can bend and break, meanwhile the other teeth are not utilized at all. Only using one or a few teeth at a time makes conventional gears inherently inefficient. 
     Meanwhile, the disclosed preferred cam devices minimize frictional loss and inefficiency, while maximizing torque throughput. In the preferred embodiments, these cam devices obtain highly efficient speed conversion because all of the cycles (&#34;teeth&#34;) of the cams work together simultaneously and synchronously (not one tooth at a time as in gears). As a result of this simultaneous synchronous action, such transmissions are inherently more efficient than the gear assemblies they are intended to replace. 
     Furthermore, the flatness of these cam disk devices permits fabrication out of space-aged materials, such as ceramics and epoxies, in addition to conventional materials. Thus these cam devices are inherently more efficient and can operate at higher temperatures with longer operating life compared to convention gears made with conventional materials. 
     The high volumetric and operational efficiency of the present invention has many benefits in energy and performance-conscious applications. And the seamlessly-shifting and variable feature of the transmission disclosed herein will yield improved user comfort. 
     A preferred coaxial, in-line embodiment of the invention has an input drive source (e.g., an electric motor) coupled to a primary input shaft which rotates primary drive cam. The rotating cam drives balls radially in a first set of radial slots of reaction disk, and these balls in turn drive secondary driven cam, which in turn rotates the output shaft. 
     A control drive source (e.g., an electric motor) rotates control drive cam. The rotating cam drives balls radially in a second set of radial slots of the reaction disk, and these balls in turn are reacted by the secondary cam which is fixed to the local ground, and the drive motor is mounted to the local ground. 
     The reaction disk is rotatably mounted on the input shaft. When the control motor is at rest, the reaction disk is grounded via the balls between grounded secondary cam 222 and the at rest primary control cam 216, the angle of attack of the balls to the primary control cam being essentially perpendicular and therefore cannot create a rotary tangential force adequate to backdrive the motor. Therefore, essentially all of the input rotation of primary drive cam will be converted to rotation of the output secondary cam, at the appropriate speed reduction, because the grounded reaction disk cannot be backdriven and is fixed in space. As well, the control motor therefore does not have to react the torque on the reaction disk from the primary drive. Grounding of the reaction disk is necessary to oppose its tendency to rotate (if unconstrained) in view of the torque which it is reacting. 
     When the control motor is energized and begins to rotate, the reaction disk begins to rotate at the speed reduction dictated by the relationship of the cams, which lessen the constraints against reaction disk rotation, since the balls begin to drive in the slots which in turn drives the reaction disk in a rotary motion. And this direction is consistent with the tendency of the reaction disk to rotate. Therefore the reaction disk will rotate as permitted by rotation of the control motor, even though the rotating control motor does not have to react the torque on the rotating reaction disk because the reaction disk is not backdriveable into the control motor. 
     The present invention preferably incorporates the teachings of U.S. patent application Ser. No. 670,263, filed Mar. 14, 1991, entitled: SPEED CONVERTER, incorporated herein by reference, and PCT Patent Application Serial No. PCT/US92/02023, filed Mar. 13, 1992, entitled: SPEED CONVERTER, incorporated herein by reference. In such disclosures, the drive cam has at least one cycle and the driven cam has a plurality of cycles, wherein the angle G separating the slots must be greater than the angle r subtended by each of the driven cam cycles, for decreasing speed at the output. The minimum angle G is computed as ##EQU1## 
     Or the angle G separating the ball slots must be less than the angle r subtended by each of the drive cam cycles, for increasing speed at the output. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features and advantages of the present invention will be more fully understood by reference to the following detailed description in conjunction with the attached drawing in which like reference numerals refer to like elements and in which: 
     FIG. 1 is a schematic view of an variable speed automotive transmission embodiment of the invention. 
     FIG. 2 shows the basic elements of the speed reducer of the invention. 
     FIG. 3 is a schematic view of a seamlessly-shifting, variable speed vehicular transmission with high speed mode according to the invention. 
     FIG. 4 is a multi-stage embodiment of the invention of FIG. 3. 
     FIG. 5 is a schematic view of a preferred seamlessly-shifting, variable speed vehicular transmission according to the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A single-stage embodiment of the present invention is shown in FIG. 1 as part of a motor vehicle. Variable speed reducer assembly 10 includes a housing 12, a plurality of interacting elements (e.g., balls 14), a drive cam member 16 coupled to a rotary input source 18 (e.g., an engine or motor) via input shaft 20, and a driven cam member 22 coupled to the wheels 24 of the vehicle via output shaft 26. A slotted reaction disk 28 is coupled to housing 12 via control assembly 30. The drive member is mounted in housing 12 by means of an input bearing or bushing and the driven member is mounted in housing 12 by means of an output bearing or bushing. Preferably the drive member and the driven member are each symmetrical about the drive axis A. 
     The basic components of a 12:1 speed reducer are shown in FIG. 2, wherein the drive cam member 16 includes a drive cam disk 16a with a single cycle drive cam track 16b formed in the face thereof; and the multi-cycle driven cam member 22 includes a driven cam disk 22a with a multi-cycle driven cam track 22b formed in the face thereof. The balls 14 oscillate in slots 29 of the slotted reaction disk 28 as the balls are driven by the rotating drive cam track 16b, and these oscillating balls, by their cooperation with the flanks of the multi-cycle driven cam track 22b, rotate the driven cam disk 22a with a reduction ratio based on the number of cycles of the driven cam member to the number of cycles of the drive cam member. 
     In the preferred embodiment, all cams of the invention cooperate as conjugate pairs. Each pair is considered to be conjugate because they must satisfy the condition that all of the balls travel at the same constant velocity all of the time, uniformly and simultaneously, except for the moment of each ball&#39;s change of direction in the slot. The slot is longer than the anticipated ball travel and therefor does not effect this change of direction. The cams are also configured such that at this change of direction, each ball is essentially unloaded, thus reducing frictional losses. The ideal maximum number of balls is determined as one fewer than the number of cycles on the driven cam. The number of slots on the reaction disk is selected accordingly. The number of cycles on the drive and driven cams are selected according to the desired speed conversion ratio. The illustrative ratio shown herein is 12:1, but any number of cycles can be chosen so as to obtain any desired ratio. 
     A controller assembly 30 is provided for control of the reaction disk to obtain an angular velocity at a controllable and variable rate. This removes energy form the speed converter and thus provides speed conversion at a controllable and variable rate at the speed reducer output. Thus, where the reaction disk is grounded or immobilized, the speed reducer output is constant and where the grounding of the reaction disk is varied or modulated, then the speed reducer output is varied accordingly. 
     By modulating the angular velocity of the reaction disk, a seamlessly-shifting variable speed transmission is provided. As a result, the power input to the speed converter (e.g., a gasoline engine or an electric motor) can operate at its optimum speed, and the speed of travel of the vehicle can be governed by modulating the angular velocity of the reaction disk. 
     In this embodiment, the reaction disk has a toothed circumference 32, such as might form a spur gear. By means of gear 32 and is coupled to the toothed coupling 34 (such as might form a cooperating spur gear) on the end of shaft 36 coupled to an electric control motor 38 of control assembly 30. Control assembly 30 also includes a microprocessor/driver circuit 40 for control of motor 38. The operator simply varies the speed of the control motor to control the angular velocity of the reaction disk so as to regulate the delivery of the speed converter input from engine 18 to the speed converter output 22 (coupled to the vehicle&#39;s wheels 24), and thus to control the speed of the vehicle. The control motor 38 on the reaction disk can thus be driven in one direction to oppose rotation of the reaction disk, i.e., to ground it, or in the other direction to accelerate rotation of the reaction disk, according to the desired vehicular speed. 
     Preferably the control motor 38 is provided with a second set of windings 42 so that when the motor is undriven and &#34;freewheeling&#34;, it can act as a generator to capture the rotary energy being bled from the system via the reaction disk. Alternatively, a stand-alone generator can be used for this energy recapture function. The generator is coupled to a battery 44 for storage of the recaptured energy. 
     Turning to FIG. 3, a seamlessly variable vehicular transmission 100 with high speed mode is shown according to an alternative practice of the invention. A motor or engine 102 is coupled via shaft 103 and gear 104 to the input disks 105, 106 of variable speed reducer assemblies 107, 108 via respective gears 109, 110 and shafts 111, 112. (Alternatively, these gears 109, 110 are formed on the back of the input cam disks 105, 106.) 
     Variable speed reducer assembly 107 comprises an input drive cam track 114 on the face of drive cam disk 105 and an output driven cam track 116 on the face of driven can disk 121, interacted by balls 120 which travel in the slots (see slots shown in FIG. 2) of reaction disk 120. The output at driven cam disk 121 is coupled via shaft 122 to gear 124, which is coupled via cooperating gear 126 ultimately to the wheels 128 of the vehicle. 
     The other variable speed reducer assembly 108 also comprises an input drive cam track 130 and an output driven cam track 132 interacted by balls 136 which travel in the slots (described earlier) of reaction disk 138. The output from the driven disk 139 is coupled via shaft 140 to gear 142, which is coupled via cooperating gear 126 ultimately to the wheels 128 of the vehicle. 
     Speed reducer assembly 107 is designed to obtain a low speed reduction, and includes the cooperating gears 104, 109, 124 and 126 and the cooperating cam tracks 114, 116. This is a low torque high speed loop which acts as a high speed section of the transmission. 
     Speed reducer assembly 108 is designed to obtain a high speed reduction, and includes the cooperating gears 104, 110, 142 and 126 and the cooperating cam tracks 130, 132. This is a high torque, lower speed loop which acts as the primary drive section of the transmission. 
     Both of these primary and high speed mode sections cooperate interactively and seamlessly for continuous regulation of the output drive to the wheels 128. This is achieved wherein reaction disks 120, 138 are selectively grounded to the equipment housing via their respective peripheral circumferential gear contours 144, 146, and a respective gear 150, 152 of a respective controller device 154, 156. 
     The controller devices 154, 156, and the motor/engine 102 operate under the control of computer/processor 166. The computer also responds to inputs from accelerator, ignition, speedometer and brake circuits 168, all via conductors 169. This control function is based upon the realization that when a reaction disk is ungrounded, there is no appreciable transmission of rotary input to the loaded speed reducer output. Thus, for example, when reaction disk 138 is entirely grounded and reaction disk 120 is ungrounded (e.g., freewheeling), all available rotary throughput is conveyed through speed reducer assembly 108 toward the wheels. Likewise, when reaction disk 120 is entirely grounded and reaction disk 138 is ungrounded, all available rotary throughput is conveyed through speed reducer assembly 107 toward the wheels. 
     The control function described herein is based upon the realization that when a reaction disk is ungrounded, there is no appreciable transmission of rotary input to the loaded speed reducer output. Thus, for example, when reaction disk 138 is entirely grounded and reaction disk 120 is ungrounded (e.g., freewheeling), all available rotary throughput is conveyed through speed reducer assembly 108 toward the wheels. Likewise, when reaction disk 120 is entirely grounded and reaction disk 138 is ungrounded, all available rotary throughput is conveyed through speed reducer assembly 107 toward the wheels. 
     Preferably controller devices 154, 156 are electric motors, such as described above. Most preferably a generator device or winding 158, 160 is coupled to the shaft 162, 164 of such motors, and these generators are coupled to a battery or other capture device 165 for recapture of rotary energy at the ungrounded reaction disks. Given this recapture ability, all of the vehicle&#39;s generator devices (e.g., generator, alternator, air conditioning compressor, power steering and power brake pumps, or the like), can be run on recaptured energy governed by their demand cycles and the demand of the vehicle speed, and optimally controlled by the computer. 
     In use, rotary input source 102 may be a constant or a variable speed source, turbo, diesel, or conventional, engine or motor, whether electric, pressurized or internal combustion.) In any event, input 102 supplies a rotary input to both speed reducers 107 and 108. Assuming a clockwise rotary input from engine 102, both speed reducer inputs will be driven counterclockwise via gears 109, 110, which motion in turn is ultimately delivered to output gear 126, for supplying clockwise drive to the wheels. Accordingly, when the vehicle is at rest, and then the engine is engaged and the accelerator is depressed, reaction disk 120 of reducer assembly 107 is driven clockwise or at least allowed to freewheel clockwise, under control of controller 154 as instructed by computer 166; at the same time reaction disk 138 of reducer assembly 108 is grounded by its controller 156, so that the engine drive input energy at gears 104 and 110 is applied to wheels 128 via speed reducer assembly 108 and gears 142, 126. 
     At the same time, the output of speed reducer assembly 108 is also coupled at the same time via gear 126 to the output gear 124 of speed reducer assembly 107. Gear 124 will thus be driven counterclockwise thereby, which will act through driven cam disk 121 as an input to speed reducer 107 and will drive the clockwise-turning, ungrounded or freewheeling reaction disk 120 clockwise according to the difference between the angular velocity of the counterclockwise driven drive and driven cams 105, 121. The thus driven reaction disk 120 is coupled via gears 144 and 150 to generator 158 for recapture of the lost rotary energy thereat for storage, such as in battery 165, so as to obtain maximum operating efficiency. A like arrangement occurs when reaction disk 120 is grounded and the ungrounded reaction disk 138 is driven by output 139 of speed reducer assembly 108, via gears 124, 126, 142. 
     As the vehicle approaches operating speed, the driver relaxes on the accelerator, and the computer begins to enter into a speed maintenance mode. In this mode, the reaction disks 120, 138 are controlled so as to apply the maximum drive input energy to the high speed mode speed reducer assembly 107. This is done by partly or fully grounding reaction disk 120 of assembly 107, via control of controller 154, while partly or fully releasing reaction disk 138 of reducer assembly 108 via control of controller 156. Computer 166 continuously polls the controllers, engine 102, and the accelerator, ignition, battery, speedometer and brake circuits 168, and directs action of the transmission and engine accordingly. The generators 158, 160 recapture lost energy at the rotating reaction disks, accordingly. 
     As will be appreciated by a person skilled in the art, the controller devices 154, 156, and the motor/engine 102 operate under the control of computer/processor 166. This computer/processor is conventional. The computer responds to inputs from accelerator, ignition, speedometer and brake circuits 168, all via conductors 169. This is analogous to the closed loop control system of conventional &#34;cruise control&#34; systems on many motor vehicles. 
     For illustrative purposes the speed reduction of the high speed mode speed reducer assembly 107 might be 1:1, while for the primary reducer assembly 108 it might be 6:1. Assuming that reaction disk 120 is freewheeling and that reaction disk 138 is fully grounded, a 4000 RPM input might result in perhaps about 40 MPH. If reaction disk 108 were slowly ungrounded, this wheel speed would be reduced accordingly down to zero, again assuming that reaction disk 120 is freewheeling. 
     As reaction disk 138 approaches being fully grounded, and the vehicle is traveling at a desired speed, then the computer can begin to transfer the transmission function to the high speed mode reducer assembly 107 by beginning to ground reaction disk 120 and beginning to unground reaction disk 138 by degrees, under control of computer 166. When reaction disk 120 is fully grounded and reaction disk 138 is ungrounded, then the transmission is in full high speed mode. Assuming the 4000 RPM input, and 6:1 speed reduction for reducer assembly 107, this would result in perhaps 80 MPH. Also, the engine speed could be increased or reduced accordingly, or both reaction disks could be permitted to rotate as determined by the computer while charging battery 165, even without changing engine speed, all under computer control. 
     A reverser assembly 170 is further provided for putting the vehicle in reverse. This may be provided in an arrangement in which the drive cam, reaction disk and driven cam are still used, although with variation of the cam curvature and ball geometry. Thus it is possible to engage a reverse motion drive selectively as needed according to the invention via an appropriate clutching/shunting arrangement. 
     The above embodiment has a primary and a high speed mode drive loop. Additional loops can be added for greater efficiency in changing from one to another speed reduction. Also, several speed reduction stages can be mated to obtain greater speed reduction. The seamlessly-shifting aspect of the invention still obtains in these embodiments. 
     A preferred coaxial, in-line embodiment 200 of the invention is shown in FIG. 5, having an input drive source 201 (e.g., an electric motor) coupled via coupling 202 to primary input shaft 203 which rotates primary drive cam 204. The rotating cam 204 drives balls 205 radially in a first set of radial slots 207 of reaction disk 209, and these balls in turn drive secondary driven cam 210, which in turn rotates the output shaft 211. 
     A control drive source 214 (e.g., an electric motor) rotates control drive cam 216. The rotating cam 216 drives balls 218 radially in a second set of radial slots 220 of reaction disk 209, and these balls in turn are reacted by the secondary cam 222 which is fixed to housing 224. Drive motor 201 is mounted to housing 225 which in turn is fixed to housing 224, establishing local ground. 
     Reaction disk 209 is rotatably mounted on a bearing 226 mounted on input shaft 203. When the control motor 214 is at rest, the reaction disk 209 is grounded via balls 218 between the grounded secondary cam 222 and the at rest primary control cam 216, the angle of attack of the balls to the primary control cam being essentially perpendicular and therefore the force from the reaction disk cannot create a rotary tangential force adequate to backdrive the motor. Therefore, essentially all of the input rotation of primary drive cam 204 will be converted to rotation of the output secondary cam 210, at the appropriate speed reduction, because the grounded reaction disk cannot be backdriven and is fixed in space. As well, the control motor therefore does not have to react the torque on the reaction disk from the primary drive. Grounding of the reaction disk is necessary to oppose its tendency to rotate (if unconstrained) in view of the torque which it is reacting. 
     When the control motor is energized and beings to rotate, the reaction disk beings to rotate at the speed reduction dictated by the relationship of the cams 216 and 222, which lessen the constraint against reaction disk rotation, since the balls begin to drive in the slots which in turn drives the reaction disk in a rotary motion. And this direction is consistent with the tendency of the reaction disk to rotate. Therefore the reaction disk will rotate as permitted by rotation of the control motor, even though the rotating control motor does not have to react the torque on the rotating reaction disk because the reaction disk is not backdriveable into the control motor. 
     According to the above embodiments, for any constant angular velocity and rotary motive force input, the output will rotate at a constant angular velocity and rotary motive force at the converted output speed, when the retainer is fixed, or will be modulated if the retainer angular velocity and rotary motive force is modulated. 
     This invention has a multiplicity of applications, including: automotive transmissions, robotics applications, elevation drives, and the like. Various modifications of the specific embodiments set forth above are also within the spirit and scope of the invention. Nevertheless, the scope of these and other embodiments is limited only as set forth in the following claims.