Abstract: A continuous V-belt transmission comprising: a primary pulley and a secondary pulley individually including two sheaves supported on shafts and made axially movable relative to each other; a belt made to run on the two pulleys; mechanical actuators individually including first members and second members for moving the movable sheaves of the two pulleys on the basis of the relative rotations of the two members: and pressure regulating mechanisms for applying an axial force corresponding to a transmission torque to at least one of the pulleys. In an unshifted state, the rotations of the pulleys are transmitted from the externally threaded portions integrated with the movable sheaves to the carriers of the planetary gear mechanisms so that they are transmitted through the ring gears to toe internally threaded portions on the basis of the sun gears being stopped. At this time, the externally threaded portions and the internally threaded portions are rotated integrally with the pulleys at the same r.p.m.

Abstract: The sliding transmission disk of a motorcycle automatic transmission is provided with a shaft sleeve having a spring seat. Located at the bottom of the spring seat is a receiving frame in which a compression spring and a turning and sliding member are disposed.The turning and slding member serves to prevent the compression spring from being acted on by a twisting force of the sliding transmission disk, thereby enabling the compression spring to rebound effectively to stabilize the decelerating action as well as the braking action of the motorcycle. The drive belt of the motorcycle is enabled to retrieve with precision so as to permit the motorcycle to be accelerated again after the decelerating and the braking actions.

Abstract: Pulley, in particular suitable for application in a continuously variable transmission, in which an endless belt can be fitted between the discs of the pulleys, the path of which endless belt can be influenced by a cylinder/piston device. The cylinder/piston device is provided with at least one pressure chamber provided with walls, one of the walls being provided with a resilient hinge, as a result of which elastic expansion of the wall around the hinge is achieved at relatively high pressures in the pressure chamber. Therefore, the shaft, along which at least one of the discs is axially displaceable, is not clamped and deformed to a lesser extent under heavy load, so that the action of the transmission is not impeded.

Abstract: An apparatus and a method for generating same provides a pulley sheave inner face profile for a variable pulley of a continuously variable transmission allowing the crowned face chain-belt centerline to remain in a plane substantially perpendicular to the axis of the pulleys at all times and at all drive ratios. Given a primary pulley sheave inner face profile, a corresponding secondary pulley sheave inner face profile can be developed to achieve substantially perfect belt alignment. The pulley sheave inner face profiles may be designed to be identical or congruent. Congruent pulley sheave inner face profiles can be developed according to an algebraic solution allowing numerically controlled design and manufacturing techniques in the fabrication of the sheave inner faces.

Abstract: A continuously variable transmission is provided comprising a driving sheave mounted on a driving shaft, a driven sheave mounted on a driven shaft, and an endless V-belt for transmitting torque between the shafts. The driving sheave includes first and second sheave members, and the driven sheave includes third and fourth sheave members. A first plurality of angularly spaced apart helical ramps formed in the driving shaft contain rolling elements which cooperate with the first sheave member. Upon application of torque through the driving shaft, the first sheave member is axially biased toward the second sheave member like the translation of a nut on a threaded screw. A similar arrangement on the driven shaft axially biases the third sheave member toward the fourth sheave member upon application of torque through the driven sheave.

Abstract: Several embodiments of snowmobiles driven by an engine and variable belt transmission mechanism wherein the variable belt transmission has its input shaft journaled for rotation in the crankcase of the engine and driven from the engine crankshaft through a gear reduction so that the transmission loads are not carried by the crankshaft and wherein the crankshaft torsional vibrations are not transmitted to the transmission input shaft.

Abstract: A variable transmission or variator uses a particular V-belt pulley. This pulley is connect to a flexible link for transmitting a driven or driving force. The pulley consists of two disklike sheaves which are variably pressed together. To reduce power losses, bearings for the sheaves assure that the sheaves are either non-loaded or not loaded parallel, but rather are variably inclined to each other. Then, the groove between the sheaves is at its maximum width approximately at the points where the belt leaves the driving pulley and comes onto the driven pulley.

Abstract: A continuously variable transmission including at least a primary pulley fixed to a primary shaft, a secondary pulley fixed to a secondary shaft and an endless transmission element located between the primary and secondary pulleys. A slip preventor is included to control and/or prevent slip of the endless transmission element with respect to the pulleys. A clutch and incorporated to the slip preventor in order to allow the amount slip to be adjusted based on factors such as the torque transmitted by the transmission.

Abstract: This invention relates to a belt driven continuously variable transmission having a pressure regulating cam mechanism giving an axial force corresponding to the transmission torque to a pulley and preventing too much belt pressing force. A retainer is fixed on a boss section of a stationary sheave and a spring made of multiple disc springs is situated on the outer surface of a boss section of a movable sheave for contact the retainer. A spring apparatus is composed of the retainer and the spring. Accordingly, at the decelerating range with large shifting ratio, besides the axial force made by the pressure regulating cam mechanism, the spring apparatus generates pressing force by contacting the retainer and maintains the belt holding force. When the shifting ratio is small, the spring returns to its natural length and disengages from the retainer.

Abstract: Auxiliary equipment in a vehicle such as dynamo, fan, pumps etcetera are coupled to an engine by a continuously variable transmission. The pump is connected to the secondary shaft of the transmission, whereas the rest of the equipment is coupled to the shaft 9 via a controllable clutch. Engaging of the clutch takes place with a signal provided by per example a Pitot tube fixed to a secondary pulley of the transmission in dependence on the number of revolutions of the shaft.

Abstract: A non-stage automatic transmission for vehicles includes a pair of adjustable pulleys supported for rotation within a transmission casing, and an endless metal belt which is wound around and frictionally engaged with the pulleys for rotation therewith. A mechanism for supplying lubricating oil between the belt and the pulleys is provided, along with an arrangement for directing lubricating oil, which has been scattered from the belt onto the transmission casing, back toward the belt.

Abstract: A control system for controlling hydraulic pressure in a dual pass continuously variable transmission includes a pump to provide primary and secondary hydraulic pressures for regulating the pulley ratio and belt tension. A minicomputer regulates the primary and secondary pressures, and a transition mechanism alternates the paths of the primary and secondary pressures between first and second pulleys of the transmission so that the primary pressure is fed to the drive pulley and the secondary pressure is fed to the driven pulley.

Abstract: In a continuously variable transmission with a pulley having discs (1, 2) wherebetween a driving belt (12) runs, at least one of the discs is movable for influencing the transmission ratio of the transmission. The moveable disc (1; 2) being mounted on a shaft (3), by support members (5; 7; 16, 18; 20, 21) possibly formed eccentrically relative to the shaft (3).The support members take up the forces exerted by the driving belt (12) close to the point of application of the forces, so that in particular the movable pulley disc may be constructed less rigid, with a smaller mass and at a reduced cost price.

Abstract: A power train configuration for a continuously variable transmission includes a slippable start clutch located upstream of a belt and sheave system and a pair of non-dynamic forward-reverse clutches located down stream of the continuously variable component. The clutch capacities of the pair of forward-reverse clutches are marginally greater than the maximum torque capacity of the engine but marginally less than the torque at which the belt of the belt and sheave system slips.

Abstract: A continuously variable belt transmission of the type comprising: primary and secondary pulleys, each of which comprises a pair of axially opposed sheaves supported on a shaft, one of the sheaves being movable and the other being fixed; a belt wound around these pulleys; a pressure adjusting mechanism for imparting to at least one of these pulleys an axial force which corresponds to torque transmitted; and mechanical actuators for axially shifting the movable sheaves of these pulleys, wherein: first thrust bearings are respectively interposed between the backsides of the movable sheaves and one ends of the mechanical actuators; a first automatic aligning mechanism is provided for supporting at least one of the races of each the first thrust bearing; and axial forces occurring at the pulleys are carried by the shafts directly, or via the first thrust bearings, the first automatic aligning mechanisms and the mechanical actuators, or via the pressure adjusting mechanism.

Abstract: A method for manufacturing a disk for a belt-driven continuously-variable-speed drive of the type which includes a metal belt disposed in engagement between mutually facing sheave surfaces which form a V-groove, including the steps of machining each sheave surface with a numerical control lathe to form therein a spiral groove that is centered about the center of the pulley and has a surface roughness within the range of 0.8-0.4 microns, and thereafter super finishing the sheave surfaces to produce residual stress therein.

Abstract: A treadmill having a walking belt with a constant speed drive motor and a transmission for adjusting the speed of the walking belt. The transmission employs input and output variable pitch pulleys to effect the belt speed change. The pulleys employ adjustably spaced sheaves to accomplish the change in speed ratio. The input pulley sheaves are adjusted by a speed change motor while the output pulley sheaves employ internal springs to adjust the sheave separation to the main drive belt joining the two pulleys. A speed reset motor is employed to keep the output pulley rotating while the sheave separation in the input pulley is adjusted for minimum walking belt speed after the main drive motor is shut down to insure that the main drive belt adjusts properly on the output pulley.

Abstract: A belt-type continously variable transmisison having an automatic clutch is provided with fixed and variable pulley elements on the driving pulley so configured as to permit some degree of slippage upon clutch engagement. Also disclosed is an engine speed control system particularly adapted for utilization with the described transmission.

Abstract: A continuously variable transmission having pulleys mounted on parallel input and output shafts and an endless belt engaging both pulleys for power transmission from the input shaft to the output shaft. The pulley on the output shaft is split into axially spaced halves having facing conical surfaces for variation of the radius at which the belt engages such pulley. One or both halves of the pulley on the output shaft have threaded bores mating with threaded portions of the output shaft.

Abstract: In a speed-shifting device of a variable speed pulley type, a transmission ratio is changed by an inversely synchronized operation between a movable sideplate of the driving and driven pulleys. The tension is given to a belt by a bias mechanism biasing the slack part. In addition, the bias mechanism can be arranged to be movable for decreasing the tension of the belt to serve as a clutch mechanism interrupting the power transmission between the pulleys.

Abstract: A continuously variable transmission has a drive pulley having a movable disc, a driven pulley having a movable disc, and a belt engaged with both pulleys. The amount of offset between a center line of the drive pulley and a center line of driven pulley is set so that the offset between center lines of both the pulleys at a pulley ratio for providing a maximum belt speed becomes zero.

Abstract: A transmission unit for self-propelled vehicles, comprising two pulleys, i.e., a driving pulley and a driven pulley, with variable pitch, connected to each other by a transmission belt, is provided with an engine start-up device with an actuation group acting downstream the driven pulley; such an actuation group causes, at start-up time, the jockey element to act on the transmission belt, for the purpose of recovering possible slack of the belt; furthermore, lock elements, disengageable by centrifugal force, are provided, which mutually constrain, at start-up time, the two half-pulleys which compose the driven pulley, for the purpose of preventing the belts from wedging themselves between the same half-pulley.

Abstract: A strap device for a pulley of a continuously variable transmission wherein a flexible strap has one end secured to the axially movable sheave of the pulley and the opposite strap end is secured to the cover encompassing the movable sheave, which cover is mounted on the rotary shaft for the pulley. To prevent buckling of the strap under reverse torques, a safety stop in the form of a pin is mounted in the cover to project into a slightly arcuate axial slot in the sheave hub and prevent undue relative rotation between the sheave and cover.

Abstract: To balance twisting torques acting on transmission chain pressure elements (11) located in an asymmetrical wedge zone between a friction disk (7,8) which has an essentially radially directed, plane face and a disk having a divergent, essentially conical engagement surface (14), the centers of curvature (17,18) of the friction surfaces (15,16) of the engagement elements are so positioned that the product of the engagement force components (20,21) acting parallel to the axes of rotation of the disks, and the radial spacing (a) of the contact points (19',23') at which the force components act is essentially equal to the product of the radially directed component (24) of the pulling force of the chain, when in operation, and the spacing (b') measured in a direction parallel to the respective shaft, of the contact point (23') of the pressure element with the disk having the substantially conical divergent engagement surface (14) from the center (C) of the pressure element, measured in its length direction.

Abstract: A belt and pulley construction for use in a continuously variable power transmission arrangement. In one embodiment the conical working surfaces of the drive pulleys and the driven pulleys are comprised of removable segments formed of relatively erodable friction modifying material so that the conical pulley surfaces will wear away before the drive belt. In another embodiment the drive belt, whether comprised of a rubber compound or of metal, contains wear faces or pads which contain friction modifying material. Traction between the belt and the pulleys can thus be controlled by members other than solely through the tension of the drive belt.

Abstract: A belt driven automatic transmission for producing a continuous range of drive ratios includes an input pully rotatably mounted on the axis of an engine crankshaft and an output pulley rotatably supported on the axis of the transmission output shaft. The pulleys are driveably connected by an endless drive belt, whose radial position on the pulleys varies in accordance with the position of axially displaceable sheaves that move in accordance with the magnitudes of pressure in actuating cylinders. The pulley system is driveably connected to the impeller of a hydrokinetic torque converter whose turbine is driven from the impeller. The turbine is continously connected to the output shaft. A forward and reverse planetary gearset is driven from the transmission selectively in accordance with the position of synchronizer sleeve.

Abstract: A bicycle is provided with an automatically variable gear ratio drive by employing a frame having a bifurcated truss rotatably supporting an axle for the rear wheel, this axle being fixed to the rear wheel for rotation therewith. A pedal assembly is positioned intermediate the wheels with a one-way clutch on the pedal assembly and a pulley is mounted on the rear wheel axle, this pulley being constituted by two laterally separated segments which are laterally moveable on the axle. A belt or chain interconnects the pedal assembly with the pulley, and an idler maintains tension on the belt or chain. The inner sides of the pulley segments are sloped and the outer side portions of the belt or chain are shaped to mate with these sloping sides so that tension on the belt or chain will cause it to move inwardly on the pulley to increase the gear ratio.

Abstract: Tension in the belt of a continuously variable transmission (CVT) is sensed and utilized in the CVT control arrangement. Apparatus for sensing the centerline tension of the belt are taught; these sensors provide the required tension signal to a signal meter or the control arrangement.

Abstract: A pulley construction for use in a continuously variable power transmission arrangement. The conical working surfaces of the drive pulleys and the driven pulleys are comprised of removable segments formed of material which is relatively erodable so that the conical pulley surfaces will wear away before the drive belt. The segments are to be replaced when their surfaces have been eroded too much. The replacement of the pulley face segments is simpler and less expensive than replacing the belt, and the use of a relatively erodable pulley face prolongs the life of the belt.

Abstract: A variable diameter pulley and belt drive has a torque and pitch radius sensitive squeeze control. The variable diameter pulleys are interconnected by a flexible belt or chain. The input pulley is connected to a power source through a pair of meshing gears and a floating link. A hydraulic control mechanism establishes the desired diameter ratio of the pulleys while the floating link is responsive to the torque transmitted to adjust the center distance between the pulleys and establish the squeeze force on the belt.

Abstract: It is a matter of a variable speed drive pulley with which is associated a regulating chamber adapted to be connected to a source of fluid, this regulating chamber being sealed in particular by a seal which, coupled axially to the mobile flange, is disposed in line with an abutment spacer also defining one of the extreme positions of the mobile flange. The abutment spacer is carried by the bush of the mobile flange on the side of the bush facing the other flange, it features a transverse collar which is directed radially towards the axis of the assembly and by which it delimits, for its part, a housing in which is disposed the associated seal and, conjointly, passages are provided in a generally radial direction in said bush and the hub of the assembly.

Abstract: A variable speed drive pulley comprises a hub and two annular flange plates around the hub in face-to-face relationship. One of the flange plates is mobile axially relative to the hub. An annular diaphragm of variable cone angle has a peripheral part forming a Belleville spring washer and a central part divided into radial fingers. The Belleville spring washer bears axially on the mobile flange plate through a connection piece and an elastic material annular spacer to which the connection piece is attached. The radial fingers bear on a support piece fixed axially with respect to the hub. A fluid-tight regulating chamber is formed between the mobile flange plate, the diaphragm, the support piece and the hub. It is adapted to be connected to a source of fluid. Sealing means in one piece with the elastic material space are disposed between the connection piece and the mobile flange plate.

Abstract: A dual-pass CVT has input and output shafts, first and second intermediate shafts, and a variator engaging the intermediate shafts. A first gear drive includes a first one-way clutch engaging the input shaft with the first intermediate shaft and allowing the first intermediate shaft to overrun. A second gear drive includes a jaw clutch for engaging the input shaft with the second intermediate shaft, and also includes a second one-way clutch engaging the second intermediate shaft with the input shaft and allowing the input shaft to overrun. A third gear drive includes another jaw clutch for engaging the first intermediate shaft with the output shaft, and also includes a third one-way clutch engaging the output shaft with the first intermediate shaft and allowing the first intermediate shaft to overrun. A fourth gear drive includes a fourth one-way clutch engaging the second intermediate shaft with the output shaft and allowing the output shaft to overrun.

Abstract: To reduce contact pressure and wear-and-tear on contact surfaces of link elements of an endless chain (9) looped between spherical engagement surfaces of cone disks, the radius of curvature R of the spherical engagement surfaces, at any point of engagement with the contact surfaces of the chain link elements is greater than a theoretical radius of curvature R, which theoretical radius of curvature results when the distances of axial movement of the movable cone disks for any two transmission ratios are equal, within the range of transmission ratio of the cone disk transmission; and in which the radius D of curvature of the contact surfaces of the link elements is greater than half the width of the link elements, measured transversely to the chain when it is looped between the pairs of cone disks.

Abstract: A spring-locked variable speed pulley, such as may be used as a drive device for automotive, motorcycle or industrial applications, wherein the engagement of a spring with the side of a stopper and movable pulley piece are improved in such a manner that the pulley can be used in a wide variety of applications. The movable pulley piece is mounted on a shaft adjacent to a stationary pulley piece with the movable pulley being movable axially as well as being rotatable. A stopper and a spring are interposed between the movable and fixed pulley pieces. Pins protrude from the side of the confronting surfaces of the movable pulley piece and the stopper, which pins engage in holes formed in the ends of the spring, the holes being disposed diametrically opposite one another with respect to the center longitudinal axis of the spring.

Abstract: A compressor drive is suggested which in particular finds use as an air conditioning compressor for motor vehicles with the combustion motor being the drive unit. Thereby, the drive of compressor 10 is performed by means of a controllable V-belt variable drive 21 which can be separated from the compressor 10 by means of an electromagnetic clutch 12. Due to the known friction drive a rotational speed independency from the combustion motor can be attained for an air conditioning compressor. This is of a considerable advantage for the capacity of compressor 10.

Abstract: The pulleys of a pulley transmission, such as a CVT, are constructed such that one flange is drivingly connected to a shaft by means of a flexible, pliable, spring-like straps or a pack of relatively thin straps. Because the pulley flange which can be axially movable with respect to the shaft, is radially supported by a hub encircling the shaft, only one strap or strap-pack need be provided.

Abstract: A compact, variable speed pulley assembly is disclosed in which pulley faces are mounted to a pulley shaft for rotation with respect thereto and for relative axial displacement along the shaft. A torsion spring is connected to transmit a torque force from the shaft to at least one of the pulley faces. The pulley assembly further includes a motion damping brake which applies a sliding friction force resisting relative angular displacement between the pulley faces and the pulley shaft. This friction force damps out over-correction by the torsion spring for speed variations induced by changes in the V-belt width, machine dynamic imbalance and workpiece characteristics. Fatigue of the torsion spring is eliminated without increasing the pulley assembly bulk by providing a second compression spring or providing a conical torsion spring.

Abstract: A continuously variable belt transmission device, including driving and driven pulley assemblies on parallel axes. Each pulley assembly includes an axially fixed and an axially movable pulley member with confronting conical face which define a V-shaped groove between them whose width is variable according to axial movement of the movable pulley member wherein the axial orders of the fixed and movable pulley members are opposite in the two pulley assemblies. An endless belt assembly is fitted in a power transmitting manner in the V-shaped grooves of the driving and driven pulley assemblies, and thus by alteration of the widths of the grooves the power transmission ratio can be varied.

Abstract: A pulley device comprises a pair of discs both slidably mounted onto a driving shaft and urged by the respective coil springs, three roll pins provided in the respective discs and extending radially, and a pair of end members each having a cylindrical portion in which three axial notches are formed for receiving the roll pins. These roll pins are borne in the openings of the discs by means of the oilless bearings disposed therein for a rotation about the axis of the roll pin and for a slidable movement along the axis thereof.

Abstract: A variable speed belt drive transmission system with a driven pulley having a movable pulley half operated to move axially with generated axial forces that decrease from where the driven pulley is closed to where the driven pulley is open, the maximum generated force being from about 100 to about 120 percent of a required pulley axial force where theoretical belt slip could occur.A method for enhancing belt life by controlling belt tension with driven pulley axial force by establishing a required driven pulley axial force that decreases from where the driven pulley is closed to where the driven pulley is open, the generated force lines being from about 100 to about 120 percent of a determined pulley axial force line where theoretical belt slip impends.

Abstract: A pulley comprises two flanges. One is a fixed flange and the other is movable axially between two extreme positions, an advanced position and a retracted position. Between the two flanges is a variable transmission device such as a belt, for example. This is in contact with both flanges and is mounted so as to be movable radially relative to the flanges. With the movable flange are associated disengagable retaining means able to hold it temporarily and in a controlled manner in its retracted position. Also associated with the movable flange are control means adapted to release it. The disengagable retaining means are on the side of the extreme position of the movable flange opposite the position it occupies in the unoperated configuration. The pulley assembly is applicable to variable transmission drive systems, and in particular to variable transmission drive systems for automobile vehicles.

Abstract: A speed variator pulley comprises a pair of annular plates mounted on a hub. One of the plates is axially movable relative to the other by means of a diaphragm which, by its peripheral portion forming a dished plate spring, axially bears to rock against the said movable plate. Axially interposed between the diaphragm and the movable plate in order to form a rocking axial support, is a spacer of elastic material, which on the one hand is fastened both axially and circumferentially to the diaphragm and which on the other hand is fastened at least axially to the movable plate.

Abstract: A V-belt type stepless transmission, basically including an input pulley and an output pulley mounted on parallel input and output shafts, respectively, each of the input and output pulleys having a stationary flange and a movable flange axially displaceable relative to the stationary flange and rotatable integrally therewith; an endless V-belt lapped around the input and output pulleys to transmit power therebetween; a servo mechanism for the movable flange, constituted by a drive member having a first screw or a second screw, the first screw formed on the movable flange or on a structure integrally connected to the movable flange, the second screw threadedly engaged with the first screw for axially displacing the movable flange by rotation of the second screw relative to the first screw, and a drive mechanism for the drive member; and a cam mechanism provided at least on one of the input and output shafts to vary compressive belt gripping force of the stationary and movable flanges in proportion to the torq

Abstract: A V-belt type stepless transmission, comprising: an input pulley and an output pulley mounted on parallel input and output shafts, respectively, each pulley having a stationary flange and a movable flange axially displaceable relative to the stationary flange and rotatable integrally therewith; an endless V-belt lapped around the input and output pulleys to transmit power therebetween, a servo mechanism for the movable flange, including a drive member having a first screw or a second screw, the first screw formed on the movable flange or on a structure integrally connected to the movable flange, the second screw threadedly engaged with the first screw for axially displacing the movable flange by rotation of the second screw relative to the first screw, and a brake provided between the drive member and a transmission case for braking the drive member, and a torsion spring interposed between the movable flange and the drive member; anda cam mechanism provided at least on one of the input and output shafts to va

Abstract: A variable speed belt drive transmission system with a driven pulley having a movable pulley half operated to move axially with generated axial forces that decrease from where the driven pulley is closed to where the driven pulley is open, the maximum generated force being from about 100 to about 120 percent of a required pulley axial force where theoretical belt slip could occur.A method for enhancing belt life by controlling belt tension with driven pulley axial force by establishing a required driven pulley axial force that decreases from where the driven pulley is closed to where the driven pulley is open, the generated force lines being from about 100 to about 120 percent of a determined pulley axial force line where theoretical belt slip impends.

Abstract: A variable pulley transmission in which each pulley is constructed of a pair of flanges coupled to respective shafts, at least one flange of each pair being axially movable relative to the other flange of the same pair, the movable flange being coupled to its shaft by an external spline operative associated with the flange meshing with an internal spline on a drive member coupled to the shaft. The spline connection permits the flange to move axially while maintaining the drive coupling.

Abstract: A torque converter with a clutch mechanism in combination wherein an axially movable sheave is movable toward and away from an opposed fixed sheave, the sheaves accomodating a belt therebetween, the movable sheave being movable in accordance with movement of a centrifugal speed responsive device adjacent the movable sheave to vary the effective pitch diameter of the pair of sheaves having their opposed faces engageable by the belt, and in which a clutch mechanism axially aligned with and mounted on the torque converter is actuatable to move the movable sheave from a non-driving position wherein the belt is not in driving engagement with the sheaves to a driving position wherein the belt is in driving engagement with the sheaves, the sheaves being resiliently biased axially apart and the clutch mechanism being resiliently biased away from the movable sheave.

Abstract: The pulley automatically changes drive speed by having a V-belt engaged at different diameters on the pulley discs. One disc is fixed to the shaft while the other disc is freely rotatable and axially slidable on the shaft. The discs have different cone angles to cause the V-belt to engage the cone surfaces at different diameters so as to cause the movable disc to rotate at a different speed from the fixed disc. A cone means is provided to reciprocate the movable disc during rotation under the bias of the V-belt.

Abstract: In a thrust piece forming a component of a chain for use in a friction pulley transmission in which the chain extends around, and circulates between, pairs of pulleys mounted on associated shafts, with one pulley of each pair being a cone pulley having a conical friction face and the other pulley of each pair being a friction pulley having a friction face which is flatter than that of the associated cone pulley, the thrust piece extending substantially transversely of the length of the chain and presenting opposed end faces via which the thrust piece bears against the friction faces of a pulley pair to effect friction force transmission between the pulley pair and the chain, one end face of the thrust piece, which contacts the friction pulley of a pulley pair, is formed to present an area of contact with the friction pulley which is reduced in relation to the area of contact between the other end face of the thrust piece and the cone pulley of the pulley pair.