Abstract: A toroidal type continuously variable transmission includes an input disk mounted on an input shaft; an output disk mounted on an output shaft; and a pair of power roller bearings each of which includes an inner race, an outer race, and a plurality of rolling elements. The inner races are engaged with the input and output disks to transmit the power of the input shaft to the output shaft. The inner races, outer races, input disk and output disk are made of case hardening steel, and are each subjected to a heat treatment in which carburizing or carbonitriding, hardening and tempering are performed sequentially, and then to shot peening, and finished by grinding of a predetermined grinding portion.

Abstract: For a toroidal type continuously variable transmission, the end portion of a radial needle bearing provided for a trunnion is protruded from the inner face of the trunnion. Also, the inner face of the trunnion is made substantially flat. Therefore, the processing of the trunnion is made easy, and the holder of the thrust needle bearing can be easily positioned simultaneously. Also, the structure is arranged to enable the recess formed on the trunnion to engage with the extrusion formed on the holder, thus preventing any plane pressure from being exerted excessively on the rolling surface of the needles of the thrust needle bearing, as well as preventing the needles from falling out of the pockets of the holder.

Abstract: In an infinitely variable traction roller transmission, wherein two toric traction disks are rotatably supported opposite one another and define a toric cavity in which at least two motion transmitting traction rollers are disposed in engagement with the two toric disks and supported by trunnions, the trunnions being pivotally supported to permit changing the ratio of motion transmission between the toric disks, the toric disks each have a different cavity radius, thus causing the circles of contact of the traction rollers with the toric disk to change as the trunnions pivot to various transmission ratio positions, thereby distributing the loads on the traction rollers over a relatively large surface area thus extending the fatigue life of the traction rollers, and consequently, of the transmission.

Abstract: A continuously variable transmission comprises a transmission unit and a casing. The transmission unit includes input and output disks on a main shaft and friction rollers arranged around axes of the disks and supported by trunnions. For controlling the speed ratio of the disks, the trunnions are urged by pistons and moved synchronously along own swinging axes perpendicular to the rotating axes of the friction rollers. Neighboring ends of the trunnions are mutually connected by linkage members and pivotally supported by the casing. The pistons can be fitted into the casing 1 from the outer side thereof, and can be detachably connected to the trunnions in the casing. The transmission is provided with a linkage support member, which can be inserted in the casing from an end opening thereof and fixed thereto perpendicular to an axis of the casing.

Abstract: A power transmission device controlling a contact surface pressure on contact areas between driving surfaces and a driven surface to transmit large power while ensuring a life-span of rolling fatigue. In this device, a traction coefficient .mu. expressed by a ratio T/N is maximized, where T is the driving force transmitted from driving members to a driven member, and N is the pressing force acting on the contact areas in perpendicular directions.

Abstract: A toroidal type continuously variable transmission has input and output conical disks having opposingly-curved conical faces, and a power roller tiltably positioned between and abutting the conical faces of the input and output disks. The power roller frictionally contacts the conical faces to transmit rotational movement between the input and output disks. The power roller is tiltable about a tilting axis that extends perpendicularly to a rotational axis of the power roller to provide a continuous variation of speed ratio between the input and output disks by tilting the power roller. The radius of the curvature of the conical face that defines the input-disk conical face is reduced in the lower speed region to increase the speed ratio between the input and output disks, compared with the main curvature radius in the higher speed region.

Abstract: A toroidal type continuously variable transmission is arranged to support one disc on the input side, facing a pressure device, on the outer circumference of an input shaft through a needle bearing. The other disc on the input side is supported on the input shaft by means of a spline coupling and a flange. A cam board which constitutes a pressure device is supported on the outer circumference of the input shaft through a ball spline. Disc springs are installed between one face of the cam board and a loading nut. In this way, the number of difficult processing steps and the degree of required precision can be reduced at the same time, hence making it possible to implement the reduction of the manufacturing costs.

Abstract: In a toroidal type continuously variable transmission, an input shaft and an output shaft are arranged coaxially with each other. The front end portion of the input shaft loosely penetrates an output disk. And an angular contact ball bearing is provided between a loading nut fixed to the front end of the input shaft and an output ring rotated together with the output disk.

Abstract: The total of thrust loads acting on first, second, and third angular ball bearings upon operation of a transmission is reduced. In order to reduce torque losses of the angular ball bearings, a toroidal type continuously variable transmission is arranged so that a thrust load based on the counterforce upon operation of a compression device is received by the third angular ball bearing, and the difference between a thrust load acting on an input-side disk and a thrust load acting on an output-side disk acts on an output shaft. A thrust load corresponding the difference is received by one of the first and second angular ball bearings.

Abstract: Each of the power rollers incorporated in a toroidal-type continuously variable transmission is arranged to prevent damage such as cracks, from being created thereon when the transmission is in operation. The inner circumferential surface of each power roller is configured continuously with a smaller diametral section close to the outer edge surface, a larger diametral section on its opposite side, and a stepping portion connecting them. A needle bearing for supporting the power roller on a displacement shaft is provided inside the larger diametral section. Due to the portion of the smaller diametral section thus provided, the stress capacity is increased with respect to the tensile stresses exerted at the time of operation; thus preventing damage such as cracks, from being easily created.

Abstract: A toroidal-type continuously variable transmission is obtainable having excellent durability without generating vibration. Given each inner diameter of the power rollers as d.sub.i, the outer diameter thereof as d.sub.o, and the diameter of each pitch circle of the plural balls which constitutes the thrust ball bearings as d.sub.p, an expression of 3<d.sub.o.sup.2 /(d.sub.i .multidot.d.sub.p)<5 is satisfied. As a result, the tensile stress can be suppressed to less than its fatigue limit. Thus any damage, such as cracks, due to repeated tensile stresses in the inner diametral portion of the power rollers are reduced. Also, the maximum contact pressure is suppressed to less than its critical contact pressure in order to prevent any indentations from being formed on the surface of the raceways arranged for the power rollers.

Abstract: In order to prevent portions of a thrust rolling bearing from being worn significantly and being burned, grooves are formed on both inner and outer surfaces of a retainer so as to traverse pockets. Lubricating oil is supplied from oiling holes formed in an outer race toward the retainer. The lubricating oil supplied from the oiling holes flows through the grooves to the rolling bearing uniformly.

Abstract: In the toroidal type continuously variable transmission, durability of input-side disc 2 supported by ball spline is improved without reducing power to be transmitted. According to the present invention, spline groove is formed on the inner peripheral surface of a center hole to construct the ball spline. While one end of the spline groove reaches the back surface of the input-side disc, the other end does not reach the inner surface thereof. Since stress occurring in the disc can be mitigaled without reducing power to be transmitted, a continuously variable transmission with high performance and excellent durability can be obtained.

Abstract: A toroidal-type continuously variable transmission provides an input side disk disposed on an input shaft, an output side disk disposed on an output shaft, and a power roller for transmitting motive power of the input shaft to the output shaft while engaging both the input side disk and the output side disk, in which the input side disk, the output side disk, and the power roller made of a material are subjected to either a carburizing and grinding process or to a carbonitriding and grinding process so that effective carburized depths of the input side disk, the output side disk, and the power roller are limited to a range between 2.0 mm and 4.0 mm. The toroidal-type continuously variable transmission is capable of improving not only the rolling contact lives of the traction surfaces of the input and output side disks as well as the traction surfaces of the power rollers, but also the fatigue fracture lives of the input and output side disks and power rollers.

Abstract: In order to prevent strong bending stress given to outer rings of thrust ball bearings of power roller assemblies and to improve the durability of the outer rings, a toroidal-type continuously variable transmission has thrust needle bearings which absorb thrust load given to the outer rings as well as allow the outer rings and corresponding trunnions to be shifted from each other. Preferably, the entire circumference of the pitch circle of the balls of each thrust ball bearing overlaps with a load-absorbing region, which is one or more annular and/or arcuate regions having the same width as the needles of needle bearings radially arranged in said regions in order to absorb thrust load.

Abstract: A compact structure is provided for a continuously variable transmission, which provides a more direct application of both load and control forces at the pivot trunnion. Load forces are produced from within the pivot trunnion, providing more direct control over load forces and their effect on contact forces between traction rollers and toric discs. Control forces which establish the desired transmission ratio are applied to the pivot trunnion in a manner which substantially eliminates twisting and squirming of the support rollers. High efficiency in operation, and improved assembly is provided with the compact structure disclosed.

Abstract: A biaxial idler comprising a flexible and resilient toroid and a frame. The frame has the capability of allowing the toroid to rotate independently both about the toroid's annular axis and about a straight axis substantially orthogonal to that annular axis. The toroid's outer perimeter can thus roll in a direction parallel to the toroid's straight axis. This biaxial idler is useful in continuously variable transmissions, because it provides a simple and rugged method of transmitting torque continuously across a wide range of varying transmission ratios while suffering minimal frictive losses and wear.

Abstract: The invention resides in an infinitely variable traction roller transmission with coaxial input and output shafts, a main transmission shaft rotatably supported in spaced parallel relationship with the input and output shafts and with an input traction roller drive interconnecting the input shaft and the main shaft and further an infinitely variable traction roller transmission structure disposed on the main shaft for transmitting motion from the main shaft at variable relative speed to the output shaft via an output traction roller drive wherein the input and output traction roller drives include traction gears mounted in radial alignment respectively on the input shaft and the main shaft and an output shaft of he infinitely variable traction roller transmission and hollow shaft surrounding the input shaft and connected to one of the ring and the planet carrier of a planetary-type transmission whose other of the ring and planet carrier is connected to the output shaft and whose sun is disposed on the input s

Abstract: A roller control system for a CVT of the toroidal-race, rolling-traction type in which a roller assembly comprises a roller (1) mounted in a carriage, and in which operating mechanism (10) contacts and applies a predetermined control force to the carriage whereby to control the manner in which its roller transmits torque and ratio between the two dics with which it is in contact, and in which the roller assembly is located by only three contacts with adjacent components namely the two disc/roller contacts and the contact with the operating mechanism. The roller centre (6) can move along the roller axis (5) relative to the carriage, and the carriage and the operating mechanism are connected by way of a hinged joint (7) with a single degree of freedom. The preferred operating mechanism is of piston (11, 12) and cylinder (13, 14) type. The axis (8) of the hinge may lie between the operating mechanism and the roller, or (e.g. at 40, FIG. 4) may pass through the operating mechanism itself.

Abstract: A compact structure is provided for an continuously variable transmission, which provides a more direct application of both load and control forces at the pivot trunnion. Load forces are produced from within the pivot trunnion, providing more direct control over load forces and their effect on contact forces between traction rollers and toric discs. Control forces which establish the desired transmission ratio are applied to the pivot trunnion in a manner which substantially eliminates twisting and squirming of the support rollers. High efficiency in operation, and improved assembly is provided with the compact structure disclosed.

Abstract: For achieving a reduced manufacturing cost and a light weight, a toroidal type continuously variable transmission is provided with a trunnion having a base formed of an appropriately machined cylindrical member, and a pair of pivots protruding from both end surfaces of the base, wherein a second center axis of the pivots is offset from a first center axis of the base toward the position at which a power roller is arranged.

Abstract: A toroidal type continuously variable transmission intended to prevent an increase in weight of the rear end portion when constructing a automobile transmission and restrain vibrations and noised during an operation. An input shaft is rotated by a crankshaft of an engine through a gear transmission mechanism provided at the front end. The rotations of this input shaft are transmitted to input disks via a driving gear, a driven gear, an external rotary cylinder, cam plates and rollers. Power rollers rotate with rotations of the input disks. The rotations of the power rollers are transmitted to an output shaft via output disks, whereby the output shaft is rotated.

Abstract: A ratio-varying component for a continuously-variable-ratio transmission of the toroidal-race rolling-traction type, in which each roller (20) spans the toroidal clearance between its respective input (4, 5) and output (11, 12) discs diametrically and the roller center (20b) is capable in operation of limited movement back and forth along the center circle (22a) of the clearance, and in which stop means (40, 41; 30, 33) are mounted adjacent both the outer and inner edges of the part-toroidal races (22, 23) on the discs, to prevent the rollers from running off the edges.

Abstract: In a toroidal type continuously variable transmission having an input disk, an output disk and power rollers sandwiched and frictionally engaged between the input and output disks so as to transmit rotational power therebetween at a transmission ratio variable according to the inclination of the power rollers relative to the input and output disks, a stationary shaft is provided as supported by a housing, and the input and output disks are rotatably supported by the stationary shaft via individual radial bearing means and individual axial bearing means. The stationary shaft has an axial bore and transverse orifices, and the bearings are lubricated by lubrication oil supplied through the axial bore and the transverse orifices.

Abstract: A ratio-varying component for a transmission of the toroidal-race rolling-traction type, in which each of the rollers (1) transmitting torque between an input disc (51, FIG. 3) and a corresponding output disc (40) is positioned hydraulically by means of an attached hydraulic piston (5) and cylinder (6) combination, in which all the cylinders lie to the same side of a common plane (43a) including the axis (43) of the discs. The cylinders may be supported on a common block-like structure (41), in which hydraulic conduits (31a, 32a, 37a, 44) may be contained.

Abstract: In an infinitely variable traction roller transmission wherein two toric traction discs are rotatably supported opposite one another so as to define therebetween a toric cavity in which at least two motion transmitting traction rollers are disposed in engagement with the toric discs and supported by trunnions which are pivotally supported to permit changing the ratio of motion transmission between the toric discs, each pivot trunnion has a cylindrical cavity with a support piston disposed therein in axial alignment with the traction roller supported on the trunnion and a plurality of radial lever members are arranged around the axis of the support piston and rest on a fulcrum structure disposed around the cylindrical cavity and, at their inner end, on the support piston, and a bearing disc which carries the traction roller is supported on the radial lever members at a location inwardly from the fulcrum structure to force the traction roller into engagement with the toric discs with the piston force amplified

Abstract: A continuously variable transmission in which a transmission unit provides a variable speed ratio between an input member (2) and an output member (3). The output member drives an output transmission member (11) by way of a power recirculation system (7-10) in a first regime of the transmission, through a selectable transmission path (30-34) providing a fixed ratio drive from the input member to the output transmission member, and having a selectable regime which provides a transmission path (19-23) from the output member to the output transmission member. The transmission is arranged so that only a clutching operation is required to effect a synchronous changeover between regimes.

Abstract: A shift control system for a continuously variable traction roller transmission controls the feedback to a shift control valve so that a ratio b/a of a variation "b" mm of a feedback amount to the shift control valve for 1 mm of a displacement of a power roller to a variation "a" mm of the feedback amount to the shift control valve for 1 degree of an inclination of the power roller is in a range given by: 1.74R.sup.4/5 -3.90.ltoreq.b/a.ltoreq.3.09R.sup.5/9 +30.51.

Abstract: The drive hub for a vehicle, particularly a bicycle, comprises a hub axle 1, a hub sleeve 9 adapted to rotate in relation to the hub axle 1 and a driver 13 mounted to rotate on the hub axle 1. The driver 13 drives the hub sleeve 9 through a friction gear 17 of which the first toroidal disc 25 is rotationally rigidly connected to the hub axle 1, of which the second toroidal disc 27 is connected to the driver 13 via a ratchet free wheel coupling 23 and drives the friction wheel carrier 43 which is provided with a plurality of friction wheels 35 and which is, in force-locking manner, connected to the hub sleeve 9 via an expanding coupling 20. The infinitely adjustable transmission ratio of the friction gear 17 is controlled from within the hub axle 1 via a linkage 53 which, via a coupling ring 47, entrains the pivotally mounted lever 39c of the pivot frames of the friction wheels 35.

Abstract: A thrust cam device is located at a back side of an input disc to bias the input disc toward an output disc in accordance with a torque applied thereto. The thrust cam device includes a drive cam, a back surface of the input disc, groups of cam rollers each being between respective cam surfaces of the drive cam and input disc, and a cam holder disposed between the drive cam and the input disc for rotatably holding the cam rollers. A disc spring is compressed between the input disc and the drive cam for constantly biasing the input disc toward the output disc. The input disc, the cam holder and the drive cam have respectively positioning holes which can be aligned. The positioning hole of the input disc is threaded. Upon requirement of preassembly of the thrust cam device, the input disc, the cam holder and the drive cam are turned to certain positions wherein the positioning holes are aligned, and a bolt is inserted into the aligned positioning holes and screwed into the threaded positioning hole.

Abstract: A rotatable disc (1, 3) formed with a coaxial part-toroidal race (26, 27) for use as the input or output disc of the variator for a transmission--especially of the full toroidal kind--of the toroidal-race rolling-traction type, in which the torus radius (r.sub.d) of the race, that is to say the radius of curvature of the race measured at a chose point on the race and in a plane including the disc axis, decreases as the distance of that point from the disc axis (5) diminishes. Such decrease of the torus radius may be either continuous or discontinuous.

Abstract: A continuously variable speed transmission mechanism comprises a tubular input shaft connected at an end to an input unit, an output shaft positioned coaxially with the input shaft, connected at an end to an output unit and extending at the other end into the hollow part of the input shaft, an input disk rotatably mounted on the output shaft and adapted to rotate by the driving force transmitted from the input shaft, an output disk fixed on the output shaft and adapted to rotate by the driving force transmitted from the input disk through power rollers, and a thrust bearing positioned between the other end of the output shaft and a corresponding part of the input shaft thereby enabling mutual rotation of the shafts. Wherein the reactive force applied to the input disk at the transmission of driving force is received by the thrust bearing through the input shaft, while the reactive force applied to the output disk is also received by the thrust bearing through the output shaft.

Abstract: A continuously variable traction roller transmission comprises a transmission casing for housing traction roller transmission units and a forward/reverse change-over device, and a wall member detachably disposed therein between the traction roller transmission units and the forward/reverse change-over device.

Abstract: An input disc and/or an output disc of a variable-speed drive, as of the toroidal type, has a central boss portion for attachment to a shaft and a radially extending flange portion with an annular concave power-roller engaging surface. An opposite surface of the flange portion is an annular convex surface having a plurality of radial reinforcement ribs formed thereon. In one preferred form, the ribs have upper surfaces which are inclined so that the front edges thereof are lower than the rear edges thereof in a rotational direction of the disc.