Patent ID: 6261203
Filing Date: 2001-07-17
Classification: F16C,F16H,Y10T

Abstract:
A toroidal-type continuously variable transmission, comprising:a rotatable input shaft;an input-side disk formed concentrical with said input shaft and rotatably supported in conjunction with said input shaft, said input-side disk including an inside surface being a concave surface formed in an arc-shaped section;an output-side disk rotatable with respect to said input shaft and including an inside surface opposed to said inside surface of said input-side disk, said inside surface being a concave surface formed in an arc-shaped section;a plurality of trunnions each swingable about said associated pivot shaft situated at a torsional relation with respect to said input shaft;a plurality of displacement shafts each supported in the intermediate portion of said trunnion in such a manner that said displacement shaft projects from an inside surface of said trunnion;a plurality of power rollers each including a peripheral surface formed in a spherical-shaped convex surface, said power roller each being rotatably supported in the periphery of said displacement shaft in such a manner that said power roller is disposed on the inside surface of said trunnion and is interposed between said input-side and output-side disks; and,a radial needle roller bearing rotatably supporting said output-side disk on said input shaft;wherein said radial needle roller bearing includes a plurality of needle rollers, the two end portions of each of said needle rollers in the axial direction thereof are crowned, and the crowning amount is set such that, in the portion of said needle roller that is situated by 7-13% of the axial-direction length toward the axial-direction central portion of said needle roller from the axial-direction end face of said needle roller, said crowning amount is 0.1-0.4% of the outside diameter of said axial-direction central portion of said needle roller.