Abstract: A variator assembly comprising a variator of the toroidal-race rolling-traction type. The assembly has input and output discs and rollers which are acted on by hydraulic roller control actuators. They are positioned between the discs to transmit torque from one disc to the other. Hydraulic end loading means supplied with fluid at an end load pressure to apply an end load to bias the discs and the rollers toward each other, thereby enabling the transmission of torque. Reaction pressure supply means are connected to the roller control actuators to cause them to apply an adjustable reaction force to the rollers. The assembly also has hydraulically influenced valve means which serve to compare an input related to the end load pressure with an input related to the reaction pressure and to control the end load pressure in dependence upon the comparison, thereby maintaining a relationship between the end load and reaction pressures.

Abstract: A toroidal-type continuously variable transmission, has first and second disks respectively including inner surfaces; power rollers interposed for transmitting power; a pressing device for pressing the first disk toward the second disk; a main oil pressure control unit for non-electrically detecting the power for setting, as a target value, an oil pressure necessary for the pressing device when a transmission ratio between the first and second disks is a transmission ratio requiring a maximum pressing force, and increase the target value as the pressing force increases; an oil pressure correcting apparatus for electrically finding a necessary value of the oil pressure, the necessary value corresponding to the optimum value of pressing force generated by the pressing device, and also for introducing an oil pressure of a value into the pressing device, the oil pressure of the value being obtained by subtracting a correction value from the target value.

Abstract: A hydraulic control circuit is disclosed for a continuously variable transmission comprising a continuously variable ratio transmission unit (“variator”) 10, the circuit comprising a supply line 106 and means (which may take the form of a pump 110) for providing a flow of pressurised fluid in the supply line, means (which may comprise a pressure control valve 116) for generating a back pressure in the supply line, and at least one connection for feeding fluid from the supply line to a hydraulic actuator 100 acting on a movable torque transmission 23-37 element (which may comprise a roller 28) of the variator 10. The valve means 152 connected to the supply line allows pressure in the supply line to be selectively modified in response to rate of flow in the supply line.

Abstract: A continuously variable planetary gear set is described having a generally tubular idler, a plurality of balls distributed radially about the idler, each ball having a tiltable axis about which it rotates, a rotatable input disc positioned adjacent to the balls and in contact with each of the balls, a rotatable output disc positioned adjacent to the balls opposite the input disc and in contact with each of the balls such that each of the balls makes three-point contact with the input disc, the output disc and the idler, and a rotatable cage adapted to maintain the axial and radial position of each of the balls, wherein the axes of the balls are oriented by the axial position of the idler.

Abstract: A variator for a toroidal transmission, with a driving disk and with a driven disk, between which is set up a toroidal space which defines a toroidal reference circle. The variator, further, comprises at least two rollers which are arranged in the toroidal space for torque transfer between the driving disk and the driven disk. The rollers are in each case mounted rotatably on a roller carrier. The roller carriers are in each case spatially adjustable by means of a piston/cylinder arrangement, in order to adjust the transfer ratio of the variator. The pistons of the piston/cylinder arrangements are in each case adjustable along a stroke axis. Also, the pistons are connected to the roller carriers via respective levers.

Abstract: When, with engine kept stopped, driven road wheels are turned, the toroidal type continuously variable transmission is suppressed from shifting toward a higher speed side. That is, when, with the engine kept stopped, the road wheels are turned in a reverse direction due to a traction of a motor vehicle with its front end facing backward, an extra oil pump driven by the road wheels produces an oil pressure which is applied to a hydraulic servo mechanism to keep a speed change ratio at a lower speed side. While, when, with the engine kept stopped, the road wheels are turned in a forward direction due to a traction of the motor vehicle with its front end facing forward, the oil pressure produced by the extra oil pump is not practically used. Under this condition, a biasing spring suppresses a servo piston from moving in a direction to bring about a speed change ratio for the higher speed side.

Abstract: In a toroidal continuously variable transmission, a primary oil pump is driven by an engine, whereas a secondary oil pump is driven in response to rotation of a road wheel. A hydraulic servo mechanism is connected to a trunnion to create an offset of the trunnion from a neutral position for a tilting motion of the power roller. Also provided is a hydraulic system that supplies the hydraulic pressure discharged from the secondary pump to the hydraulic servo mechanism to prevent the offset of the trunnion in the trunnion-axis direction, corresponding to an upshift, occurring owing to rotation of the road wheel in a stopped state of the engine. A modulated hydraulic pressure, which is constantly produced by the hydraulic system during operation of the engine, acts to hold the secondary pump at either of an inoperative state and an unloaded condition during the operation of the engine.

Abstract: A toroidal type continuously variable transmission, in which an input disc and an output disc are arranged on the common axis with being opposed to each other in the rotatable condition, and in which the rolling member is arranged between the input disc and the output disc, so as to transmit a torque between said input disc and said output disc through said rolling member, by applying the clamping force to said input disc and said output disc in said axial direction, characterized by comprising a clamping force controller for controlling the clamping force to be applied to said input disc and said output disc based on a physical quantity relevant to heat stress of said rolling member.

Abstract: In a continuously variable transmission with a toroidal variable speed drive, in which a roller is supported pivotably between two toroidal disks for transmitting motion between the two toroidal disks at transmission ratios which depend on the pivot position of the roller according to pressure forces acting on a hydraulic actuating piston, for the purpose of varying the transmission ratio, two regulating slide valves are provided, each including a regulating slide with control edges to act upon the hydraulic actuating piston via a hydraulic medium under the control of the regulating slide valves each controlling the pressure in one of the chambers arranged at opposite ends of the actuating piston.

Abstract: A toroidal type continuously variable transmission; in which a rolling member for mediating the transmission of a torque is clamped between at least a pair of rotary members; and in which a clamping force for clamping the rolling member in the direction not to let the rolling member be released from between the rotary members is applied to the rolling member, comprises: a detector for detecting temperature rise of either, a temperature of a rolling face of the rotary members for clamping the rolling member, or a temperature of the rolling member; and a rolling member controller for reducing the clamping force in case a temperature rise is detected by said detector.

Abstract: A lubrication device for a toroidal type continuously variable transmission, which can set the speed change ratio continuously by transmitting a torque inputted from a power source by rolling members contacting each other through an oil film, and by varying the position of the contact portion of those rolling members steplessly, characterized by comprising: an auxiliary hydraulic power unit for generating an oil pressure without relying on said power source, a preliminary operation detector for detecting whether or not the preliminary operation relative to the start up of said power source is executed, and a preliminary lubricating mechanism for feeding the lubricating oil to the contact portion between said rolling members by means of said auxiliary hydraulic power unit before starting up said power source, when the preliminary operation is detected.

Abstract: A hydraulic circuit for a continuously variable transmission having a continuously variable ratio unit that is controlled by at least one hydraulic actuator acting on a movable torque transmission element. The actuator has opposed first and second working chambers. The circuit includes first and second flow lines that are connected to two respective actuator working chambers. The lines feed fluid thereto and therefrom A pressurized supply of fluid urges fluid flow through the flow lines. A variable control valve is incorporated in both flow lines. Each valve generates an adjustable back pressure therein. A further valve is connected between the two flow lines. The further valve has a variable opening and is located upstream of the variable control valve. Opening of the further valve enables flow fluid from one flow line to the other to reduce pressure difference between the lines.

Abstract: In the inner and outer surfaces of the retainer 34b, there are formed recessed grooves 40a, 40a which serve as lubricating oil flow passages for allowing lubricating oil to flow into pockets. Where the axial-direction depth of the recessed groove 40a, 40a is expressed as H and the circumferential-direction width thereof is expressed as 2L, 0.20?H/L?0.97 can be satisfied. Accordingly, it is possible to provide a toroidal-type continuously variable transmission which can prevent the damage of a retainer 34b incorporated into a thrust rolling bearing for supporting a power roller and also can enhance the lubricating efficiency of the present thrust rolling bearing.

Abstract: A control unit for an infinitely-variable-ratio transmission. The transmission includes a cylinder and a piston with a proximal and a distal end. A support stem is connected to the piston. The piston is hollow and has a head portion for interaction with an associated actuation fluid. A proximal portion extends away from the head portion. The support stem is connected to the proximal portion by an articulated joint and extends from the joint to the head portion to exit from the distal end of the piston.

Abstract: A variator assembly is disclosed comprising a variator of the toroidal-race rolling-traction type having input and output discs, rollers which are acted on by hydraulic roller control actuators and are positioned between the discs to transmit torque from one disc to the other and hydraulic end loading means (200) supplied with fluid at an end load pressure to apply an end load to bias the discs and the rollers toward each other thereby enabling the transmission of torque. The assembly further comprises reaction pressure supply means connected to the roller control actuators to cause them to apply an adjustable reaction force to the rollers. In accordance with the invention hydraulically influenced valve means (204) are provided which respond to the reaction pressure and the end load pressure to control the end load pressure and thereby maintain a relationship between the end load and reaction pressures. Further adjustment means (350) to adjust the relationship between the end load and reaction pressures.

Abstract: In a toroidal continuously variable transmission the amount of traction oil provided to contact areas between the power rollers and the input and output discs is increased as a power to be transmitted is increased. Nozzle holes formed in rockable trunnions of the transmission so that the traction oil ejected from the nozzle holes is sprayed to circumferential positions of inner surfaces of input and output discs that are in contact with peripheral surfaces of power rollers. Transmission efficiency is enhanced while maintaining endurance and reliability without supplying excessive traction oil.

Abstract: A toroidal-type continuously variable transmission, has first and second disks respectively including inner surfaces; power rollers interposed for transmitting power; a pressing device for pressing the first disk toward the second disk; a main oil pressure control unit for non-electrically detecting the power for setting, as a target value, an oil pressure necessary for the pressing device when a transmission ratio between the first and second disks is a transmission ratio requiring a maximum pressing force, and increase the target value as the pressing force increases; an oil pressure correcting apparatus for electrically finding a necessary value of the oil pressure, the necessary value corresponding to the optimum value of pressing force generated by the pressing device, and also for introducing an oil pressure of a value into the pressing device, the oil pressure of the value being obtained by subtracting a correction value from the target value.

Abstract: A toroidal-type continuously variable transmission includes three trunnions and power rollers in a single cavity. One of the trunnions is shifted by a pair of oil pressure actuators, each of a single-acting type. The remaining two trunnions are respectively shifted by separate oil pressure actuators, each of a double-acting type.

Abstract: A control system (34) suitable for controlling the rollers (26) in an infinitely-variable-ratio transmission (10) is provided with an hydraulic piston arrangement (36) in which a roller support stem (38) is connected to a proximal end (42) of said piston and passes through a piston head (40) via hollow portion (44) within said piston (36) before exiting therefrom.

Abstract: When, with engine kept stopped, driven road wheels are turned, the toroidal type continuously variable transmission is suppressed from shifting toward a higher speed side. That is, when, with the engine kept stopped, the road wheels are turned in a reverse direction due to a traction of a motor vehicle with its front end facing backward, an extra oil pump driven by the road wheels produces an oil pressure which is applied to a hydraulic servo mechanism to keep a speed change ratio at a lower speed side. While, when, with the engine kept stopped, the road wheels are turned in a forward direction due to a traction of the motor vehicle with its front end facing forward, the oil pressure produced by the extra oil pump is not practically used. Under this condition, a biasing spring suppresses a servo piston from moving in a direction to bring about a speed change ratio for the higher speed side.

Abstract: A toroidal type continuously variable transmission includes a pair of discs (5, 10) in opposed relation, and a rotary element (17) interposed in a toroidal clearance (S) defined between these discs (5, 10). Torque is transmitted between the pair of discs (5, 10) via the rotary element (17). Sensing the velocity of the rotary element (17) permits the determination of, for example, how much the rotary element (17) slips on the discs (5, 10). This assists the prevention of heat-up of the rotary element (17) and also provides an optimal traction between the rotary element (17) and the discs (5, 10).

Abstract: In a toroidal continuously variable transmission (TCVT) control apparatus with a variator unit and a ratio control hydraulic system, an electronic TCVT control unit electronically feedback-controls a transmission ratio based on a deviation from a desired transmission ratio, and generates a normal-period command signal to be input to a step motor for compensating for the deviation. The control unit determines whether the deviation can be compensated for by electronically feedback-controlling the transmission ratio based on the deviation and generates an abnormal-period command signal to be input to the step motor to realize a step-motor displacement capable of shifting or diverging the transmission ratio to a speed-reduction side, while keeping a trunnion out of contact with a stopper in the direction of the trunnion axis, when the deviation cannot be compensated for by electronically feedback-controlling the transmission ratio based on the deviation.

Abstract: In a toroidal continuously variable transmission, a secondary oil pump is provided in addition to a primary oil pump driven by an engine. The secondary oil pump is driven in response to rotation of a road wheel. A hydraulic servo mechanism is connected to a trunnion to create an offset of the power roller from a neutral position for a tilting motion of the power roller. A feedback device is provided for feeding a degree of progress for ratio changing back to the hydraulic servo mechanism so that the power roller returns to the neutral position when a desired transmission ratio has been reached. When the road wheel is rotated in a stopped state of the engine, hydraulic pressure from the secondary oil pump is supplied to the hydraulic servo mechanism so that an actual transmission ratio is brought closer to a desired transmission ratio.

Abstract: A ratio control for a toroidal-type traction drive comprises toroidal discs defining a toroidal cavity. Traction roller assemblies have pivot trunnions rotatably supporting traction rollers. A ratio control element is provided, which is positionable to establish various ratios between the toroidal discs. A feedback structure is connected to the ratio control element and includes a ratio control valve to hydraulically control the traction roller assemblies, and a cam follower. A feedback cam is provided, which cooperates with the cam follower. A lost motion cam actuator is provided between a predetermined pivot trunnion and the feedback cam to permit limited independent deflected movement of the predetermined pivot trunnion from the pivot axis thereof without requiring corresponding movement of the feedback cam.

Abstract: A speed change control system is equipped with a feedback mechanism which feeds back the gyration angle of a power roller and the axial displacement of the power roller, to a speed change control valve (100) via a speed change link (12). The feedback mechanism comprises a cam plate (2) which outputs a feedback amount according to the gyration angle of the power roller, an L-shaped link (7) which outputs a feedback amount according to the axial displacement of the power roller, and a feedback link (3) connected to the cam plate (2) and L-shaped link (7), and connected to the speed change link (12). The feedback gain of the feedback amount according to the axial displacement of the power roller due to the L-shaped link (7), is varied according to the gyration angle of the power roller.

Abstract: A speed change control valve (7) houses a spool (8) of comprising a land (83) which can face a supply port (7P) supplying an oil pressure, and lands (84, 85) which can respectively face a pair of drain ports (7D, 7D) formed on either side of the supply port (7P). Output ports (7L, 7H) which allow a first and second oil chamber of an hydraulic cylinder to communicate selectively with the supply port (7P) or the drain ports (7D) according to the displacement of a spool (8), are provided in the speed change control valve (7). In the neutral position of the spool (8), the lands (84, 85) respectively face the drain ports (7D), a width L1 of the land (83) is set to be equal to or greater than a width L1 of the supply port (7P), and a width L3 of the lands (84, 85) is set to a width at which the drain port (7D) can open.

Abstract: A toroidal type continuously variable transmission transmits a torque from an input disk to an output disk through a plurality of groups of rollers interposed between the input disk and the output disk. Respective carriages for the rollers are connected to one another by a connecting member. A hydraulic actuator collectively applies forces against torque transmission reactive forces respectively received by the rollers to the rollers through the connecting member and the corresponding carriages.

Abstract: The present invention provides an hydraulic control circuit for a continuously-variable-ratio transmission An hydraulic control circuit for a CVT transmission includes a first hydraulic pressure control valve V1 for controlling the pressure of hydraulic fluid to be supplied to the roller control pistons of the variator and a second hydraulic pressure control valve V2 for controlling the pressure of hydraulic fluid to be supplied to a clutching arrangement of the transmission. Said valves V1, V2 are connected in flow series and by a first fluid directing valve means V3(S1, S2) for directing flow from each pump PL, PR to a first point P upstream of valve V1 or to a second point P downstream of valve V1 but upstream of valve V2. By adopting such an arrangement it is possible to control the clutches without affecting the roller position and vice versa.

Abstract: The toroidal-type continuously variable transmission comprises a hydraulic loading mechanism of an oil pressure type for pushing an input disk toward the disposition side of an output disk to thereby transmit the rotation power of the input disk to the output disk, and a countersunk spring incorporated in a hydraulic chamber formed in the loading mechanism for elastically pushing the input disk toward the disposition side of the output disk. In the toroidal-type continuously variable transmission, there are formed a plurality of slits in the countersunk spring and, when oil is supplied into the inside area of the countersunk spring within the hydraulic chamber by and from a hydraulic pump, the oil in the inside area of the countersunk spring is allowed to flow through the slits into the outside area of the countersunk spring.

Abstract: In a toroidal type continuous variable speed transmission, a control valve for displacing trunnions is controlled by supporting and fixing a precess cam at an end of a rod displaced together with one of the trunnions. Therefore, when the torque inputted to the toroidal type continuous variable speed transmission is greatly varied by the treading on or releasing of the accelerator, there is the risk that an unnecessary variation of the gear ratio invite an abrupt change in engine revolutions and a consequent uncomfortable feeling on the part of the driver. A tip of a link arm is brought into contact with the cam face of a precess cam, and the control valve is switched according to any variation of the trunnion. Further, the contact position between the cam face and the tip of the link arm is placed closer to the input side disk side. This configuration makes it possible to suppress the influence of elastic deformation of trunnions and to solve the problem noted above.

Abstract: A lubricating system for a toroidal continuously variable transmission equipped with a trunnion rotatably supporting a power roller gripped between input and output disks so that a gyration angle of the power roller is variable, includes a first lubricating circuit provided for lubrication of a rolling contact surface on which the input and output disks are in friction-contact with the power roller, and a second lubricating circuit provided for lubrication of the trunnion and the power roller. Also provided in the first lubricating circuit is an oil-temperature control device that heats oil of the toroidal continuously variable transmission, so that the oil temperature-controlled by the oil-temperature control device is supplied through the first lubricating circuit into the rolling contact surface.

Abstract: In order to stabilize an operation for changing a speed change ratio, and to improve transmitting efficiency and endurance of structural parts of a toroidal continuously variable transmission, a relationship between the switching of a control valve and displacements of trunnions is such that initiation of the displacement of a trunnion having a feedback mechanism including a precess cam and a link arm is effected prior to initiation of the displacement of a trunnion not having a feedback mechanism.

Abstract: In a toroidal continuously variable transmission, a secondary oil pump is provided in addition to a primary oil pump driven by an engine. The secondary oil pump is driven in response to rotation of a road wheel. A hydraulic servo mechanism is connected to a trunnion to create an offset of the power roller from a neutral position for a tilting motion of the power roller. A feedback device is provided for feeding a degree of progress for ratio changing back to the hydraulic servo mechanism so that the power roller returns to the neutral position when a desired transmission ratio has been reached. When the road wheel is rotated in a stopped state of the engine, hydraulic pressure from the secondary oil pump is supplied to the hydraulic servo mechanism so that an actual transmission ratio is brought closer to a desired transmission ratio.

Abstract: Disclosed is a supply of hydraulic actuation and cooling fluid to the roller actuation pistons and rollers provided in an infinitely variable transmission. The transmission assembly (10) includes a split casing (12a, 12b) and a manifold (28) that comprises one or more channels (30, 32, 60) formed in a surface of the casing formed by the split. The provision of said manifold in this position allows for easier manufacture and better performance.

Abstract: A ratio control for a toroidal-type traction drive comprises toroidal discs defining a toroidal cavity. Traction roller assemblies have pivot trunnions rotatably supporting traction rollers. A ratio control element is provided, which is positionable to establish various ratios between the toroidal discs. A feedback structure is connected to the ratio control element and includes a ratio control valve to hydraulically control the traction roller assemblies, and a cam follower. A feedback cam is provided, which cooperates with the cam follower. A lost motion cam actuator is provided between a predetermined pivot trunnion and the feedback cam to permit limited independent deflected movement of the predetermined pivot trunnion from the pivot axis thereof without requiring corresponding movement of the feedback cam.

Abstract: A control valve system for controlling the ratio of a traction drive variator comprising a pair of toroidal torque input discs and a pair of toroidal torque output discs with torque transmitting rollers situated between the disc. A pair of pressure actuators which establish the position of the rollers relative to the torque input discs and the torque output discs. Pressure differential across the pressure actuators is controlled by a valve assembly comprising a ratio valve connected to a valve actuating lever, one end of the lever being activated by an adjustable element of the variator and the other end being activated by a ratio stepper motor. A cam and lever arrangement is used to translate movement of the rollers in a motion feedback fashion to the ratio valve so that a null position of the ratio valve will be established as pressure differential across the actuator reaches a null state.

Abstract: The friction gear has an input shaft (3) an a torque shaft (20) arranged in a position coaxial thereto, two input disks (5, 12) and output disks (6, 11) disposed in pairs and between which friction wheels are placed and fastened to carriers (26). In the upper section (39) of the housing of the gear recesses (35) are provided in which the upper ends (36) of the carriers (26) engage with play.

Abstract: When a slip control system starts operating, a vehicle speed VSP used for speed change control is simultaneously changed over from a sensor detected vehicle speed VSPSEN to an estimated vehicle speed VSPFL. On the other hand, when the slip control system has stopped, it is first determined whether a speed ratio variation amount, due to the change-over of the vehicle speed used for speed change control from the estimated vehicle speed VSPFL to the sensor detected vehicle speed VSPSEN, is less than a permissible amount. When it is determined that the speed ratio variation amount is smaller than the permissible amount, the vehicle speed used for speed change control is changed over from the estimated vehicle speed VSPFL to the sensor detected vehicle speed VSPSEN. By performing this change-over, a sharp variation of the vehicle speed used for speed change control is suppressed, and a sharp variation of the speed ratio leading to shocks or slipping is suppressed.

Abstract: A speed change control system is equipped with a feedback mechanism which feeds back the gyration angle of a power roller and the axial displacement of the power roller, to a speed change control valve (100) via a speed change link (12). The feedback mechanism comprises a cam plate (2) which outputs a feedback amount according to the gyration angle of the power roller, an L-shaped link (7) which outputs a feedback amount according to the axial displacement of the power roller, and a feedback link (3) connected to the cam plate (2) and L-shaped link (7), and connected to the speed change link (12). The feedback gain of the feedback amount according to the axial displacement of the power roller due to the L-shaped link (7), is varied according to the gyration angle of the power roller.

Abstract: In a toroidal type continuous variable speed transmission, a control valve for displacing trunnions is controlled by supporting and fixing a precess cam at an end of a rod displaced together with one of the trunnions. Therefore, when the torque inputted to the toroidal type continuous variable speed transmission is greatly varied by the treading on or releasing of the accelerator, there is the risk that an unnecessary variation of the gear ratio invite an abrupt change in engine revolutions and a consequent uncomfortable feeling on the part of the driver. A tip of a link arm is brought into contact with the cam face of a precess cam, and the control valve is switched according to any variation of the trunnion. Further, the contact position between the cam face and the tip of the link arm is placed closer to the input side disk side. This configuration makes it possible to suppress the influence of elastic deformation of trunnions and to solve the problem noted above.

Abstract: A roller control unit for a CVT includes a cylinder (54) having a piston (70) positioned therein and operably connected to a roller assembly of said CVT thereby to control its position. The unit includes a lubrication supply which comprises a chamber (94) between the cylinder (54) and piston (70) and one or more radially extending passageways (102) through said piston (70). These passageways are in flow communication with the roller and act to direct cooling fluid to said roller. Radial supply of said lubrication facilitates a reduction in flow losses within the supply.

Abstract: In an infinite speed ratio transmission device comprising a continuously variable transmission (2), fixed speed ratio transmission (3) and planetary gear set (5), a final output shaft (6) is provided to extract the rotation output of the planetary gear mechanism (5). The output gear (3B), a sprocket (4A) and transmission device output gear (7) are formed on a final output shaft (6). The output gear (3B) engages with an input gear (3A) of the fixed speed ratio transmission (3), and the device output gear (7) engages with the final gear (12). The output of the continuously variable transmission (2) is transmitted to the sprocket (4A) via a chain (40). Of the gear set of the input gear (3A) and output gear (3B) and the gear set of the device output gear (7) and final gear (12), one set comprises helical gears having helical tooth traces.

Abstract: A toroidal type continuously variable transmission transmits a torque from an input disk to an output disk through a plurality of groups of rollers interposed between the input disk and the output disk. Respective carriages for the rollers are connected to one another by a connecting member. A hydraulic actuator collectively applies forces against torque transmission reactive forces respectively received by the rollers to the rollers through the connecting member and the corresponding carriages.

Abstract: A power roller (18c) comprises a power roller inner wheel (93) in frictional contact with a input/output disks (18a, 18b), a power roller outer wheel (94) provided in a trunnion (17a), a ball bearing (92) interposed between the power roller inner wheel (93) and the power roller outer wheel (94), and an inner wheel supporting shaft (95) which supports the power roller inner wheel (93) such that it is free to rotate, the shaft having a shaft base part (95b) supported in the trunnion (17a), and arranged so that the radial support rigidity is set high in a gyration axis direction and set low in the direction perpendicular to the trunnion gyration axis (19a) and the power roller rotation axis (15d). When one of the disks is pressed and displaced in the direction of the other disk by the press member, the power roller inner wheel (93) displaces with the ball bearing (92) by the displacement of the one of the disks.

Abstract: A roller control unit (2) for a continuously-variable-ratio transmission includes a cylinder (6) having a cylinder wall and an end wall; and a piston (8), within the cylinder (6) and to which the roller assembly (4) is connected for movement therewith, said unit includes an axially extending shroud (10) of variable length extending between the piston (8) and the end wall, thereby to define in combination with the piston (8) and cylinder (6) a chamber (16) for receiving hydraulic fluid, and in which the shroud (10) comprises a telescopic shroud which in a first position of the piston (8) is extended and in a second position of the piston (8) is retracted.

Abstract: The present invention relates to the supply of hydraulic actuation and cooling fluid to the roller actuation pistons and rollers provided in an IVT. The IVT assembly (10) includes a split casing (12a, 12b) and a manifold (28) that comprises one or more channels (30,32,60) formed in a surface of the casing formed by said split. The provision of said manifold in this position allows for easier manufacture and better performance.

Abstract: When an arm (100) of a forward/reverse detection mechanism (90) rotates, a spool (82) of a change-over valve (80) in contact with the arm (100) displaces in an axial direction, and a first valve (60) and second valve (70) are selectively connected to hydraulic actuators (50, 52, 54, 56) of a transmission (10). In order to reduce the wear and friction of the arm (100), the arm (100) is formed so that a part (102) in contact with the spool (82) is an arc, and the locus (L) of the center of curvature (A) of the arc part (102) when the spool (82) is displaced, intersects with a perpendicular line (S) dropped from a rotation center (O) of the arm (100) to a center axis (T) of the spool (82).

Abstract: A pressure control valve for maintaining a discharge pressure of an oil pump at a predetermined value is installed in a transmission integral casing integrally constituted by a torque converter housing, an oil pump cover a transmission case of a transmission is integrally connected to the torque converter housing. The transmission case has a projecting portion that extends toward the torque converter housing and is located in the vicinity of an oil discharge port of the oil pump cover. The relief valve is installed in the projecting portion and is connected to a hydraulic passage connecting the oil discharge port and an oil supply port of a transmission control valve assembly installed at a lower portion of the transmission case.

Abstract: A lower section (78f) of a piston boss (78d) of a hydraulic cylinder (80) is formed with a small radius and is inserted into a fixed gap provided with respect to the inner peripheral face of the cylinder through hole (60d). A thrust force F is applied to trunnions (46) supporting power rollers (29) and the trunnions (46) deform about a support position connected by an upper link (50) and a lower link (52). At the same time, even if the lower end (78f) of the piston boss (78d) undergoes a large inclination, no adverse effect results on the inner peripheral face of the cylinder through hole (60d). Even if the sliding section of the piston undergoes a large inclination together with a deformation of the trunnions (46), local wear and damage to the sliding face on the cylinder inner periphery can be avoided.

Abstract: A continuously variable toric transmission has rollers which engage semi-toroidal disc members to establish a drive relation therebetween. The annular disposition of the rollers relative to the toroidal members determines the speed relationship between the toroidal members. The rollers are urged into a space between the discs by one force and the discs are urged together by another force. Thus, the discs have a normal force and a traction force, the ratio of which is equal to the coefficient of traction. Controlling the ratio of the traction force to the normal force controls the coefficient of traction within a predetermined range of values. The traction force is affected by a controlled pressure differential across a piston which forces the rollers into the space between the discs, and a pressure urging the discs toward each other affects the normal force. By controlling these pressures, the coefficient of traction is controllable.