Abstract: In a toroidal type continuously variable transmission, first pivot shafts provided on both ends of first trunnions are supported within support holes formed in yokes secured to an inner surface of a casing. The support portions are provided with ball splines and radial needle bearings. During operation, loads acting on the first trunnions are cancelled within the yokes. Axial displacements and rocking displacements of the first trunnions are effected smoothly by the ball splines and the radial needle bearings.

Abstract: A toroidal-type continuously variable transmission, has: a casing; an input rotary shaft; a pair of input side disks each including an input side inner surface and respectively supported on the input rotary shaft; an output cylinder supported on the input rotary shaft; a pair of output side disks each including an output side inner respectively supported on the periphery of the output cylinder; an output rotation transmission member fixed to the outer peripheral surface of the middle portion of the output cylinder; support members interposed respectively between the input side inner surfaces and the output side inner surfaces; power rollers being contacted with the input side inner surfaces and the output side inner surfaces; and, a rolling bearing disposed between the input side inner surface and the output side inner surfaces and rotatably supporting the output cylinder

Abstract: A toroidal-type continuously variable transmission, has a first continuously variable transmission mechanism and a second continuously variable transmission mechanism: wherein the first and second continuously variable transmission mechanisms are disposed coaxially with each other; the first and second input disks are connected together so as to be rotated in synchronization with each other; the first and second output disks are formed as a unified type output disk including traction surfaces on the two side surfaces thereof; on the side portion at the outer-most outside diameter of the unified type output disk, there is formed a datum plane serving as a machining datum when the traction surfaces are processed; and, an operation for finishing the datum plane is carried out after the unified type output disk is heat treated.

Abstract: A toroidal type continuously variable transmission having first and second discs supported around a rotating shaft and receiving power rollers therebetween includes a ball spline having a first spline groove formed in an outer circumferential surface of the rotating shaft, a second spline groove formed in an inner circumferential surface of the first disc, and balls provided between the first spline groove and the second spline groove rollably. An axial position of an end portion of an effective groove portion of the first spline groove is located to correspond to an axial position of an inner end portion of the second spline groove or more closely to the second disc than the axial position thereof when a pressing unit, a preload spring and the first disc are installed around the rotating shaft, pressure oil is not fed to the pressing unit, and the preload spring is not elastically deformed.

Abstract: A toroidal-type continuously variable transmission has an input disk, an output disk, a pressing device for pressing said first disk toward said second disk, a plurality of trunnions having a pair of first support shafts for supporting a plurality of power rollers, a pair of support plates for supporting the first pivot shafts of each of the trunnions; and a pair of swing brackets each including a second pivot shaft parallel to the first pivot shaft of the trunnion, the swing brackets being respectively supported so as to be swingable about the second pivot shafts with respect to the support plates. The first pivot shafts of the trunnion are respectively supported so as to be swingable with respect to the support plates through the swing brackets.

Abstract: A toroidal-type continuously variable transmission includes an oil supply passage formed in a trunnion, for lubricating bearing parts supporting power rollers. The oil supply passage is structured by a groove formed in the inner surface of the trunnion and a plate-shaped cover member for covering the groove.

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: A disk for a half toroidal type continuously variable transmission is manufactured through the following processes. In step S1, a work as a base material mass is heated to a temperature suitable for forging. In step S2, the work is forged into the work having a portion corresponding to a protrusion of the disk using a first die set. In step S3, the work is forged into the work which has a hole corresponding to a mounting hole of the disk using a second die set. In step S4, the work is forged into the work which has a portion corresponding to a skirt portion of the disk using a third die set. In step S5, the work receives punching, machining and the like to finally obtain the disk product.

Abstract: A double-cavity toroidal-type continuously variable transmission includes a case, a drive shaft and a toroidal transmission mechanism portion. The toroidal transmission mechanism portion includes a gear housing for supporting an output gear, and a yoke for supporting a pivot shaft of a trunnion in an oscillatable manner. The support post for supporting the yoke and a fixing member for fixing the gear housing and the support post to the case are connected together or are formed as an integral body.

Abstract: In the toroidal-type continuously variable transmission, the radial clearance of a second radial needle roller bearing 30 for supporting the power roller 8 on the periphery of the pivot shaft portion 26 of the displacement shaft 7 is set larger than the radial clearance of a first radial needle roller bearing 27 for supporting a support shaft portion 25 on a trunnion 6. By increasing the radial clearance of the second radial needle roller bearing 30 in this manner, an increase in the surface pressures in the contact portions between the rolling surfaces of needle rollers 32, 32 and the inner peripheral surface of the power roller 8 and the outer peripheral surface of the pivot shaft portion 26 can be restricted, thereby enhancing the durability of the toroidal-type continuously variable transmission. Also, by reducing the radial clearance of the first radial needle roller bearing 27, the inclination of the displacement shaft 7 is minimized, thereby stabilizing the rotation speed change operation thereof.

Abstract: In a toroidal-type continuously variable transmission, at least one of components including inner and outer races of a power roller bearing, an input disk, and an output disk is composed of an alloy steel material containing C: 0.15 to 0.5 wt %, Si: 0.1 to 1.5 wt %, Mn: 0.1 to 1.5 wt %, Cr: 0.5 to 3.0 wt %, and at least one kind selected from Mo: 0.1 to 3.0 wt % and V: 0.1 to 3.0 wt %, a content of 0 in the alloy steel material being set to be not more than 9 ppm; and the surface of the at least one component after carbonitriding, hardening and tempering treatments is set to contain C: 0.8 to 1.2 wt % and N: 0.05 to 0.20 wt %, and the at least one component has surface hardness of Hv 720 or more, and Mo.V carbide/carbonitride, the average particle size of which is in a range of from 50 nm to 500 nm is dispersed and precipitated on a race surface or in a range of from the race surface to a deep position where a maximum shearing stress is generated.

Abstract: The present invention relates to a toroidal-type continuously variable transmission which comprises: a casing; input and output disks respectively including inner surfaces, disposed concentrically with each other inside the casing, and supported so as to rotated independently of each other; a plurality of trunnions each including even-numbered pivot shafts existing at right angles to a central-axis direction of the disks and disposed concentrically with to in parallel to each other, and being swingable about the pivot shafts; a plurality of shift shafts respectively projected out from the trunnions; a plurality of power rollers held by and between respective inner surfaces of the disks so as to be rotatably supported on the shift shafts; and a support member fixed directly to the casing and supporting the pivot shafts so as to be shifted in an axial and an inclined rotation direction thereof.

Abstract: A toroidal type continuously variable transmission, includes: at least one pair of disks concentrically disposed on each other and rotatably supported independent from each other; a trunnion swingable about a pivot shaft; a displacement shaft including a support shaft portion and a pivot shaft portion that are parallel and eccentric to each other, the support shaft portion rotatably supported to the circular hole of the trunnion through a radial bearing, the pivot shaft portion being protruded from an inner surface of the middle portion of the trunnion; a power roller nipped between the concave surfaces of the pair of disks while being rotatably supported on an outer circumferential surface of the pivot shaft portion; and a thrust bearings located between the power roller and the inner surface of the middle portion of the trunnions. An eccentric quantity of the displacement shaft being a distance between the support shaft portion and the pivot shaft portion is within a range from 5 mm to 15 mm.

Abstract: A toroidal-type continuously variable transmission, includes: an input shaft; a pair of mutually opposed input and output disks disposed side-by-side in an axial direction of the input shaft; a pressing mechanism pressing said input disk toward said output disk; a hollow shaft disposed around an outer periphery of the input shaft concentrically with the input shaft, and connecting the pair of input disks to each other; an oil hole formed in a no-penetrating portion of the input shaft where the input shaft does not penetrate through the hollow shaft, and opened on an outer peripheral surface of the no-penetrating portion; and, an oil passage formed between an inner peripheral surface of the hollow shaft and an outer peripheral surface of a penetrating portion of the input shaft where the input shaft penetrates through the hollow shaft.

Abstract: In the toroidal-type continuously variable transmission, the torque transmission shaft 15 includes a flange portion 29a formed in one end thereof, while a securing portion 43 is formed in the end-face side half section of the flange portion 29a so as to be able to secure a tool thereto when tightly fastening a loading nut 19 to a external thread portion 40 formed in the torque transmission shaft 15. And, the outer peripheral surface of the securing portion 43 is formed as a polygonally cylindrical shape having four or more flat surfaces. Also, after the torque transmission shaft 15 is heat-carburized and the surface of a cylindrical portion 44 formed in the torque transmission shaft 15 is removed, the external thread portion 40 is worked, which makes it possible not only to secure the hardness of the adjoining portions of the external thread portion 40 but also to control the hardness of the external thread portion 40 itself.

Abstract: In the toroidal type continuously variable transmission system 100 incorporating a power roller bearing 11 therein, race grooves 15 and 16 respectively formed in the inner and outer races 35 and 13 of the power roller bearing 11 are respectively structured in such a manner as to have an arc-shaped cross section, and the radii of curvatures of the arc-shaped cross sections of race grooves 15 and 16 are set in the range of 52% to 59% of diameter of a rolling ball body which can roll on these race grooves, thereby being able not only to restrict an increase in dynamic torque of the power roller bearing but also to improve life of the power roller bearing.

Abstract: A plural cavity toroidal transmission is designed to permit transmission of great torque between output side disks and a sleeve while maintaining a thickness of the sleeve. To this end, convex portions are formed on outer surfaces of the output side disks and concave portions are formed on edge portions of both axial ends of the sleeve. By fitting the convex portions into the concave portions, synchronous rotations of the pair of output side disks and transmission of rotation from the output side disks to an output gear can be achieved.

Abstract: In a toroidal-type continuously variable transmission, there is provided a thrust rolling bearing interposed between a power roller and a trunnion for supporting a thrust-direction load applied to the power roller. The thrust rolling bearing includes a plurality of rolling elements and a retainer rollably holding the plurality of rolling elements. The retainer defines a circular-ring-shaped main body and a plurality of pockets respectively formed in the main body for rollably holding the plurality of rolling elements. A clearance between the pocket and the rolling element is set in the range of 0.6 to 6.0% of the ball diameter of the rolling element.

Abstract: A power roller bearing of a toroidal-type continuously variable transmission unit that is used for a transmission of an automobile or the like comprises a power roller, an outer race, balls, a retainer, etc. Annular raceway grooves are formed individually on the respective opposite end faces of the outer race and the power roller. Treated-surface layers for enhancing the endurance of the power roller bearing are formed individually on the respective surfaces of the raceway grooves. The treated-surface layers include super-finished surfaces with the surface roughness of 0.05 Ra or less, formed individually on the raceway grooves, and low-friction layers formed individually on the super-finished surfaces. Alternatively, the treated-surface layers include residual compression stress layers formed on the respective surface layer portions of the raceway grooves by shot-peening.

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.