Abstract: A continuously variable transmission includes a transmission belt including a plurality of elements and a ring and wound around V-grooves of first and second pulleys, each of the plurality of elements including a body portion having a saddle surface and a pair of pillar portions extended from the body portion so as to be located on both sides in a lateral direction of the saddle surface, and the ring being disposed between the pair of pillar portions of each of the plurality of elements. When one of the first and second pulleys has its minimum groove width, at least a part in a thickness direction of the ring wound around the one of the first and second pulleys protrudes radially outward beyond an outermost circumference of a surface of the V-groove of the one of the first and second pulleys.

Abstract: A drive pulley for a continuously variable transmission (CVT) has a pulley shaft with a fixed sheave, a movable sheave and a back plate thereon. The movable sheave has a movable sheave surface with first and second surface portions that faces the back plate. A biasing member biases the sheaves away from each other. A slider is disposed between the back plate and the movable sheave. The slider has a flat engagement zone surface, and a curved driving zone surface extending outward from the engagement zone surface. From rest, as the pulley shaft accelerates, the engagement zone surface of the slider slides radially outward against the first portion of the movable sheave surface and then the driving zone surface of the slider slides radially outward against the second portion of the movable sheave thereby pushing the movable sheave toward the fixed sheave. A vehicle having the CVT is also disclosed.

Abstract: A continuously variable transmission device (1) for a two-, three- or four-wheel motorcycle comprises a gear shift regulation device provided with a slide (40) axially slidable and suitable to engage special rollers (18) to hold them during the gear shift. A mobile bushing (9) is suitable to influence the slide (40) to cause its translation from a rearward position to a forward limit position to engage the special rollers (18).

Abstract: A continuously variable transmission device (1) for a two-wheel, three-wheel or four-wheel motorcycle includes a gear shift regulation device suitable to operate on special rollers (18) through an adjustable axial action independently of the number of engine revolutions. The device influences the centrifugal movement of the rollers (18) and thus influences the gear shift.

Abstract: A slide roller is provided. A lower connecting surface of the roller is never in contact with a roller passage surface. By taking advantage of a normal distance between a corner sliding surface and a center point of the roller greater than a vertical distance between an upper sliding surface of the roller and the center point, a pulley disc assembly can be started lightly, the acceleration in the middle stage of the slide stroke is increased, and speed transmission in the rear stage of the slide stroke is increased.

Abstract: A control device that includes an electronic control unit that is configured to perform lock-up engagement pressure control for acceleration upon acceleration of a vehicle where vehicle speed is increased by increasing a rotational speed of the internal combustion engine, the lock-up engagement pressure control for acceleration controlling engagement pressure of the lock-up clutch, wherein in the lock-up engagement pressure control for acceleration, when an actual rotational speed of the input has reached greater than or equal to a reference rotational speed, the electronic control unit is configured to start engagement pressure increase control, the reference rotational speed being lower than a target rotational speed of the internal combustion engine, and the engagement pressure increase control increasing the engagement pressure of the lock-up clutch.

Abstract: A technique for providing a water pumping system suitable for fighting wildfire, flood mediation, sewage transport, and the like is revealed. The system includes an internal combustion engine, a CVT with an input shaft and an output shaft, and a pump with an axial flow impeller. In one variation, multiple impeller stages are used and/or several systems are daisy-chained to provide for suitable delivery of water from its source. In another form, the system is carried by an all-terrain vehicle, side-by-side, or the like, to reach remote areas that need to move water to address a hazardous condition.

Abstract: A continuously variable transmission (CVT) includes a power transmission mechanism and at least one conical disk. The power transmission mechanism has a contact surface, and the power transmission mechanism includes a plurality of engaging elements. The plurality of engaging elements are retractably disposed on the contact surface. The disk surface of the conical disk has a plurality of engaging walls capable of engaging with the engaging elements. The continuously variable transmission is able to transmit power by way of engagement, such that the coupling between the power transmission mechanism and the conical disk is more stable. Thus, the continuously variable transmission is adaptable to high torsion application.

Abstract: A hybrid vehicle control device is provided with at least one controller programmed to control outputs of the engine and the electric motor, an engagement and disengagement of the clutch, and a transmission ratio of the continuously variable transmission in accordance with a driving state. The at least one controller is further programmed to restart the engine while maintaining a released state of the clutch, and downshift the continuously variable transmission to a predetermined transmission ratio for passing over the level difference upon determining that the level difference is present while traveling by a drive force of the motor with the clutch released and the engine stopped.

Abstract: A washing machine includes a cabinet, a tub disposed within the cabinet, to store wash water, a rotating tub rotatably disposed within the tub, a pulsator rotatably disposed within the rotating tub, a motor disposed beneath the tub, to provide power for rotation of the rotating tub and the pulsator, and a clutch assembly disposed between the motor and the rotating tub. The clutch assembly includes a clutch coupling movable vertically between upper and lower positions to transmit the power from the motor to at least one of the rotating tub and the pulsator, a coupling lever movable pivotally to vertically move the clutch coupling, and a clutch lever movable pivotally and operatively connected to the coupling lever to pivotally move the coupling lever.

Abstract: A power transmission unit for a vehicle including a first clutch device that selectively allows a torque transmitting route from an input shaft to an output shaft via a first gear train to transmit torque therethrough, a dog clutch that switches the torque transmitting route from the input shaft to the output shaft between a continuously variable speed change route in which the torque is transmitted through a continuously variable transmission and a reverse route in which the torque is transmitted through a second gear train, and a second clutch device that connects and disconnects both of the continuously variable speed change route and the reverse route to/from at least any one of the input shaft and the output shaft.

Abstract: A continuously variable transmission for a vehicle comprises a primary pulley, a secondary pulley, and a belt entrained around both pulleys in an opposite manner between the fixed and movable sheaves thereof. One pulley carries a selectively deployable stop that may be placed into position to mechanically limit the range of motion between the fixed and movable sheaves. This establishes an actual maximum transmission ratio that is larger than the nominal minimum transmission ratio but smaller than the nominal maximum transmission ratio achievable by the transmission during normal operation thereof. When such a transmission is used on a utility vehicle attached to a substance dispensing applicator operatively driven by the vehicle's engine, the application rate stays substantially constant despite changes in engine speed when the user keeps the transmission upshifted to the actual maximum transmission ratio set by the position of the deployed stop.

Abstract: Provided is a power transmission device for an electric vehicle including a continuously variable transmission capable of increasing the energy efficiency and performance of the electric vehicle, further lowering the engine speed of an electric motor required for shifting the continuously variable transmission so as to accelerate the automatic gear shift timing, and further saving energy by applying a V-belt continuously variable transmission to the electric vehicle using the electric motor and providing an appropriate automatic transmission according to the driving state. The power transmission includes a housing, a driving pulley assembly disposed at the driving shaft of the electric motor, a driven pulley assembly disposed at the driven shaft, a V-belt connecting the driving pulley assembly to the driven pulley assembly, and a speed-reducing gear train disposed between the wheel axis, which is rotatably supported in the housing, and the driven shaft.

Abstract: A drive pulley for a continuously variable transmission includes a fixed sheave and a movable sheave rotationally fixed relative to the fixed sheave. A housing is axially and rotationally fixed relative to the fixed sheave. At least one centrifugal actuator includes an arm pivotally connected to one of the movable sheave and the housing of the fixed sheave at a first pivot axis. The arm pivots away from the one of the movable sheave and the housing about the first pivot axis as a speed of rotation of the drive pulley increases and pushes against another one of the movable sheave and the housing thereby moving the movable sheave axially toward the fixed sheave. The arm is movable relative to the first pivot axis by pivoting the at least one arm about a second pivot axis. The second pivot axis is offset from the first pivot axis.

Abstract: A continuously variable transmission for a vehicle comprises a primary pulley, a secondary pulley, and a belt entrained around both pulleys in an opposite manner between the fixed and movable sheaves thereof. One pulley carries a selectively deployable stop that may be placed into position to mechanically limit the range of motion between the fixed and movable sheaves. This establishes an actual maximum transmission ratio that is larger than the nominal minimum transmission ratio but smaller than the nominal maximum transmission ratio achievable by the transmission during normal operation thereof. When such a transmission is used on a utility vehicle attached to a substance dispensing applicator operatively driven by the vehicle's engine, the application rate stays substantially constant despite changes in engine speed when the user keeps the transmission upshifted to the actual maximum transmission ratio set by the position of the deployed stop.

Abstract: A torque sensor for a belt-driven conical-pulley transmission. A first ramp surface is rigidly connected to a shaft of a conical disk pair, and a second ramp surface is rigidly connected to a sensing piston surrounding the shaft and axially and rotatably movable relative to the shaft. Balls are positioned between and in contact with the ramp surfaces and with a guide surface rigidly connected with an axially movable disk. The guide surface is so configured that the contact points of a particular ball with the ramp surfaces, the contact point of that ball with the guide surface, and the center point of that ball lie in a radially oriented plane.

Abstract: A V-belt type continuously variable transmission includes a drive pulley assembly provided on a drive shaft, a driven pulley assembly provided on a driven shaft, a V-belt looped over both the pulley assemblies, and a transmission case assembly housing both the pulley assemblies and the V-belt. One end of the drive shaft in the shaft direction is coupled to an output side rotation member of a centrifugal clutch, and the other end of the drive shaft is rotatably supported on a boss portion formed in the transmission case assembly.

Abstract: A belt-type continuously variable transmission (CVT) with reduced vibration at high engine speeds. A secondary sheave includes a fixed sheave member, a moving sheave member, a compression coil spring, and an outside spring guide. The compression coil spring urges the moving sheave member toward the fixed sheave member. The outside spring guide prevents the compression coil spring from buckling during compression.

Abstract: A pulley assembly for a continuously variable transmission in a vehicle, comprising a shaft having an axis, a supporting element rotatable about said axis, a first half pulley rigidly and rotationally connected to said supporting element, a second half pulley facing said first half pulley for defining a seat adapted to accommodate a belt of the transmission, at least one of the first and second half pulleys being longitudinally mobile with respect to the supporting element, and a clutch comprising a second supporting element connected to the shaft, a drum connected to the supporting element and accommodating the second supporting element, and a plurality of friction elements hinged to the second supporting element about respective hinge axes to selectively cooperate with the drum. In particular, the respective centres of gravity of said friction elements are located before the respective hinge axes with respect to a direction of rotation of the shaft which defines a forward running condition of the vehicle.

Abstract: A continuously variable transmission in which a sliding member is prevented from inclining is provided. The continuously variable transmission has a first oil passage provided in a movable sheave, and a second oil passage provided in a primary shaft supporting the movable sheave and connected in series to the first oil passage. A working oil is discharged from a hydraulic chamber via the first and second oil passages. The working oil is more difficult to discharge from the second oil passage than the first oil passage.

Abstract: A snowmobile is disclosed having improved drive train including a continuously variable transmission (CVT) having a drive belt looped around a driving pulley and a driven pulley, and a transversely arranged jackshaft wherein the driven pulley is connected directly onto the outer surface of one end of the jackshaft. The transverse jackshaft is preferably made from a thin-walled hollow tube and the driven pulley is preferably press fitted thereon. A method of assembling a snowmobile drive train is also disclosed.

Abstract: A continuously variable transmission (CVT) system including a primary clutch assembly with an engine braking assembly is provided. The primary clutch assembly includes first and second sheave assemblies, a cylindrical sleeve coupler and an engine braking assembly. The first sheave portion has a centrally extending post. The cylindrical sleeve coupler is rotationally mounted on a portion of the post. The sleeve coupler has an engaging surface that is configured to engage an inner face of a drive belt. The second sheave portion has a central passage that is rotationally mounted on the sleeve coupler.

Abstract: In a motorcycle having a V-belt type continuously variable transmission, a resin washer made of a nylon resin is interposed between a boss fixed to a moving sheave half of a secondary sheave and a spring bearing member. The boss contacts the spring bearing member through the resin washer, whereby the moving sheave half is restricted to a Top position, in which a spacing between it and a stationary sheave half becomes maximum. In this manner, the maximum speed is not changed by exchange of the V-belt, the V-belt does not slip or become considerably abraded or deteriorated, and noise generation is suppressed.

Abstract: A belt type continuous variable transmission comprises a primary sheave, a secondary sheave, and a belt. The primary sheave comprises a first sheave body, a second sheave body that forms between it and the first sheave body a belt groove, about which a belt is entrained, a plurality of push bodies that slide the second sheave body according to centrifugal forces to change a width of the belt groove, and a plurality of stoppers that restrict movements of the push bodies by contacting with outer surfaces of the push bodies when the second sheave body reaches a position of minimum transmission gear ratio, in which the belt groove is made smallest in width. The stoppers are shaped to accelerate partial wear of the outer surfaces of the push bodies.

Abstract: A V-belt continuously variable transmission (CVT) for a straddle-type vehicle includes a measurement plate for a rotational speed sensor for detecting a rotational speed of a primary sheave shaft to control a speed change ratio. The measurement plate is disposed on an opposite end of the primary sheave shaft, to one end of which a driving force of an engine is input, with respect to a primary sheave.

Abstract: A V-belt type continuously variable transmission according to the present invention includes a drive pulley assembly provided in a drive shaft, a driven pulley assembly provided in a driven shaft, a V-belt looped over both the pulley assemblies, and a transmission case assembly housing both the pulley assemblies and the V-belt. One end of the drive shaft in the shaft direction is coupled to an output side rotation member of a centrifugal clutch, and the other end of the drive shaft is rotatably supported on a boss portion formed in the transmission case assembly.

Abstract: A variable speed transmission of the continuously variable type. The transmission includes an input pulley having primary and secondary sheaves and an output pulley having primary and secondary sheaves. The primary and secondary sheaves of the input pulley are mounted on a first axle shaft carried by an actuator plate and the primary and secondary sheaves of the output pulley are carried on a second axle shaft carried by the actuator plate. The input shaft of the transmission carries pin mounted roller bearings which are received in skewed slots in an actuator sleeve so that the actuator sleeve is moved axially along the input shaft in response to variations in torque loading. The actuator plate is annular and includes a central circumferential groove receiving pin mounted roller bearings carried by the actuator sleeve so that the actuator plate, and the axle shafts carried thereby, undergoes the same axial movement as the actuator sleeve in response to variations in torque loading.

Abstract: A continuously variable transmission including a first shaft with a first pulley rotating around a first rotation axis, a second shaft with a second pulley and a belt looped around the first pulley and the second pulley whereby the first pulley comprises two discs with conical surfaces which support the belt at a first radius and which are displaceable relative to one another in the direction of the first rotation axis for changing the first radius. Both conical surfaces of the discs are provided with parallel ridges and slits parallel to the first rotation axis so that the conical surfaces intersect in a plane perpendicular to the rotation axis whereby the ridges of the one disc slot in the slits of the other disc.

Abstract: A belt-type continuously variable transmission that is easily manufactured includes a belt wound around a primary sheave and a secondary sheave. The primary sheave includes a fixed sheave member, a movable sheave member, a cam plate, and a roller weight. The movable sheave member has a guide rib extending toward the cam plate. The cam plate has a slider having a guide groove. The position of the radially outer portion of an end surface of the slider is shifted toward the right in the rotation axis extending direction from the position of the radially inner portion of the end surface.

Abstract: An improvement of the pulley set structure connects the clutch assembly by a belt for the convey of the power, comprising a variator and a fan impeller. One side of the fan impeller is designed to form a setup of indentations and protrusions, which is to boost the transmission coefficient between the fan impeller and the belt; the variator is provided with a plurality of grooves allocated with rollers or weights, a skirt portion made of a rigid wall which is located near the rim of the variator, and a plurality of vents formed onto the grooves and the skirt portion, where the purpose is to improve the dissipation of the excessive heat generated by the rolling of the rollers or weights which in turn are activated by the engine, or to improve the skid and incomplete transmission subject to inefficient friction between the pulley set and the belt.

Abstract: A belt type continuously variable transmission that includes a primary pulley; a secondary pulley; a belt where the primary pulley and the secondary pulley are bound; a positioning hydraulic chamber that presses a primary movable sheave to a primary fixed sheave; a supply-side valve that permits working oil to be supplied from the outside to the positioning hydraulic chamber; and a discharge-side control valve that controls permission or prohibition of discharge of the working oil from the positioning hydraulic chamber to the outside. The discharge-side control valve prohibits discharge of the working oil from the positioning hydraulic chamber to the outside when a position of the primary movable sheave is kept constant in the axial direction with respect to the primary fixed sheave.

Abstract: The driven pulley (10) comprises a first sheave (12) and a second sheave (40) coaxially mounted around a main shaft. The first sheave (12) is fixed with reference to the main shaft while the other sheave (40) is allowed to slide and rotate with reference to the main shaft. The driven pulley (10) is designed with a roller mounting unit (74) facilitating the assembling or the replacement of the rollers (70).

Abstract: The disengageable pulley device includes a pulley mounted on an internal transmission element, and a free wheel provided with a plurality of wedges and with a cage for the wedges, said free wheel being designed to provide one-way engagement between the pulley and the internal transmission element. The device includes an elastic connecting member provided with a first fixing part for fixing it to the internal transmission element, with a second fixing part for fixing it to the cage, and with a working part between said fixing parts, said working part being radially moveable relative to the internal transmission element and being adapted to exert a circumferential return force on the cage.

Abstract: A snowmobile is disclosed having improved drive train including a continuously variable transmission (CVT) having a drive belt looped around a driving pulley and a driven pulley, and a transversely arranged jackshaft wherein the driven pulley is connected directly onto the outer surface of one end of the jackshaft. The transverse jackshaft is preferably made from a thin-walled hollow tube and the driven pulley is preferably press fitted thereon. A method of assembling a snowmobile drive train is also disclosed.

Abstract: An engine comprises: a V-belt type continuously variable transmission on one side of an engine case, said CVT being provided with and housing in a transmission case a drive pulley attached to one end of a crankshaft, a driven pulley attached to one end of a transmission shaft parallel to said crankshaft, a V-belt routed around the pulleys, said engine case supporting said crankshaft and transmission shaft in a rotatable manner, and a generator attached to the opposite end of said crankshaft in said engine case; in which a filter chamber is disposed in the opposite side surface of said transmission case of said engine case in a depressed manner so as to overlap with at least a part of said generator in the crankshaft direction, and an oil filter for filtering lubricating oil is disposed in said filter chamber.

Abstract: A sliding centrifugal drive weight for use in an automatic transmission found in motor vehicles or watercrafts. The sliding centrifugal drive weight, which mainly consists of an outer friction shell and an inner core weight, comprises an upper inclined face in sliding contact with a ramp plate, a bottom surface in sliding contact with a movable drive pulley half, a left face, and a right wear resistant face. The sliding centrifugal drive weight is designed to eliminate abnormal wear, prevent reduction gear ratio deterioration, prolong the useful life of the transmission, and have the availability to adjust reduction gear ratios as well as driving performance. At the same time, the sliding centrifugal drive weight is also adapted to compensate wear automatically, to adjust by itself to move further outward in a movable drive pulley half, make the vehicle reach a higher maximum vehicle speed.

Abstract: The power transmission system of an engine is mounted on the all-terrain vehicle and has a crankshaft driven by the engine and the crankshaft is arranged in a direction of width of a vehicle body. A sub-shaft is arranged parallel to the crankshaft and the rotation of the crankshaft is transmitted to the sub-shaft via gears. A primary shaft is concentrically mounted on the sub-shaft and is provided with a primary pulley having a variable groove width. A secondary pulley coupled to the primary pulley via a V-belt and having a variable groove width. The rotation of the crankshaft is transmitted to the primary shaft via the sub-shaft arranged parallel to the crankshaft.

Abstract: An all terrain vehicle (“ATV”) is disclosed having a frame with front, rear, right, and left sides. An engine and at least two wheel axes are disposed on the frame. A plurality of wheels are disposed on the at least two wheel axes. The engine includes a cylinder disposed adjacent a crankshaft and a generator operatively connected to the crankshaft. An output shaft, separate from the crankshaft, operatively connects to the engine to transmit power from the engine to at least one of the plurality of wheels through at least one of the wheel axes. The output shaft is disposed between the cylinder and the generator in a plane substantially perpendicular to at least one of the wheel axes.

Abstract: A vehicle includes an engine that powers a wheel through a drive train. The drive train includes a continuously variable transmission (CVT) and toothed gearing disposed between the CVT and the wheel. A release clutch is also disposed between the CVT and the wheel. A controller controls the release clutch so as to disengage the clutch when the engine is not running and engage the clutch when the engine is running. The controller includes a hydraulic cylinder that fluidly connects to the engine's oil system so that engine-generated oil pressure engages the release clutch. Disengagement of the release clutch makes it easier to push the vehicle when the engine is not running, for example, when the engine breaks down.

Abstract: A bidirectional continuous power transmission system, characterized by a projecting bolt moving within a guiding opening with a rear wall and a front wall. Upon a rotating movement, the projecting bolt exerts a force on the rear wall or the front wall, depending on the orientation of the rotating movement. The force has a component parallel to an axis of rotation, causing two halves of a driven wheel to be pressed together and against a transmission belt. By providing the rear wall and the front wall of the guiding opening with defined curvatures, well-defined forces are exerted at any speed in both orientations of the rotating movement, so that torque is continuously transmitted effectively in both directions.

Abstract: A continuously-variable-ratio drive, having an input shaft; a flywheel integral with the input shaft; a drive pulley idle with respect to the input shaft and defined by two half-pulleys defining a groove of variable size for a V belt; and a centrifugal control assembly. The control assembly has a centrifugal actuating device which intervenes above a first threshold value of the angular speed of the input shaft to connect the drive pulley angularly to the flywheel by means of a friction clutch; and a speed adjusting device which is active over a second threshold value of the angular speed of the input shaft to adjust the size of the groove of the drive pulley and therefore the work diameter of the belt.

Abstract: The driving pulley comprises two centrifugal mechanisms, namely a positive assembly and a negative assembly. Both assemblies comprise a respective set of flyweights subjected to the centrifugal force when the driving pulley rotates. The positive assembly is used as a conventional speed governor that moves one of the two flanges of the driving pulley towards the other in order to increase its winding diameter when the rotation speed increases. The negative assembly is used to apply an opposite force on the positive assembly when the rotation speed is above a threshold value so as to defer the upshift of the CVT to a higher ratio under the action of the positive assembly. This allows to maintain, for instance, a high rotation speed during an intense acceleration and a lower rotation speed when cruising at low vehicle speeds.

Abstract: A continuously variable transmission with two conical disk pairs on the input side and two conical disk pairs on the output-side that are connected with each another by two parallel endless torque-transmitting members in a drive mechanism. In one form of the transmission an asymmetrical cone angle on the conical disks enables the installation space to be reduced.

Abstract: A continuously variable transmission (“CVT”) is disclosed. The CVT includes a drive pulley adapted to connect to a crankshaft of an engine. The drive pulley has inner and outer halves with belt engagement surfaces to engage the sides of the belt. The drive pulley of the CVT also includes a slide sleeve disposed on the shaft adapted to engage an inner side of a belt. The inner and outer halves of the drive pulley are biased apart from one another by a spring. The slide sleeve engages the belt when the belt is stationary or traveling at low speeds. The driven pulley includes inner and outer halves with belt engagement surfaces. The two halves are biased into contact with one another. A connector connects the inner half to the outer half. In addition, a pneumatically-actuated driven pulley is described together with a CVT incorporating same.

Abstract: A continuously variable transmission having an input shaft; a flywheel integral with the input shaft; a drive pulley idle with respect to the input shaft and defined by a first and second half-pulley defining a groove of variable width for a V belt; and a centrifugal actuating assembly having a centrifugal actuating device, which intervenes above a first threshold value of the angular speed of the input shaft, so as to connect the drive pulley angularly to the flywheel by means of a clutch interposed between the first half-pulley and the flywheel, and a speed regulating device, which is active above a second threshold value of the angular speed of the input shaft to adjust the width of the groove of the drive pulley, and therefore the work diameter of the belt. The actuating device has push means which exert axial thrust on the first half-pulley at each speed value of the input shaft above the first threshold value.

Abstract: An engine having an engine case on one side of which a V-belt type of continuously variable transmission is provided, the CVT being placed in a transmission case and constituted that a V-belt is routed around a drive pulley and a driven pulley, the drive pulley being attached to one end of a crankshaft, the driven pulley being attached to one end of a transmission shaft parallel to the crankshaft, characterized in that

Abstract: A variable-speed V-belt drive includes: a drive pulley; a driven pulley including a fixed sheave with a cylindrical shaft and a movable sheave mounted on the cylindrical shaft so that the movable sheave can rotate and axially move; a V belt extended between the drive and driven pulleys; and a pressure mechanism of applying pressure to the movable sheave of the driven pulley. The pressure mechanism includes a helical cam groove formed in one of the cylindrical shaft and the movable sheave of the driven pulley, and a roller mounted on other of the cylindrical shaft and the movable sheave of the driven pulley so that the roller engages with the cam groove. The cam groove has opposite first and second working surfaces. The second working surface has a retaining surface of retaining the roller thereon when the vehicle travels in the engine-braking mode. The variable-speed V-belt drive can maintain the effect of engine brake at a high level even when traveling down a steep hill.

Abstract: A continuously-variable-ratio drive, having an input shaft; a flywheel integral with the input shaft; a drive pulley idle with respect to the input shaft and defined by two half-pulleys defining a groove of variable size for a V belt; and a centrifugal control assembly. The control assembly has a centrifugal actuating device which intervenes above a first threshold value of the angular speed of the input shaft to connect the drive pulley angularly to the flywheel by means of a friction clutch; and a speed adjusting device which is active over a second threshold value of the angular speed of the input shaft to adjust the size of the groove of the drive pulley and therefore the work diameter of the belt.

Abstract: The driving pulley (12) is used in a continuously variable transmission (CVT) and comprises two flanges (22,24) around which a drivebelt (20) is partially wound. The first flange (22) is fixed in translation with reference to the drive shaft (16) while the second flange (24) is movable, with reference to the first flange (22), between a distal position and a proximal position. The driving pulley (12) is provided with an arrangement which allows the return force on the second flange (24) to be maximum when the second flange (24) is at the distal position, and minimum when the second flange (24) is at the proximal position. The driving pulley (12) is also capable of being disengaged from the drivebelt (20) at a low rotation speed. This driving pulley (12) is particularly well adapted for use on a scooter.

Abstract: A belt-type continuously variable transfer system (15) includes a driving pulley assembly (20), a driven pulley assembly (22) and a V-shaped belt (24) engaged to transfer rotary power therebetween. The driven pulley assembly (22) can include a ratio adjustment mechanism (46) that adjusts the position of a rear sheave (40) relative to a forward sheave (42). The adjustment mechanism (46) includes a motor (170) and a worm gear mechanism (171, 172) that rotates an actuation screw (154). Rotation of the actuation screw (154) is reacted by a split nut (158) so that as the screw (154) rotates is translated along the axis (B) of the driven pulley assembly (22). Translation of the actuation screw (154) exerts pressure against the rear sheave (40) to push it toward the forward sheave (42), thereby altering the drive ratio of the pulley assembly.