Patent ID: 6733415
Filing Date: 2004-05-11
Classification: F16C,F16H

Abstract:
A power roller for a toroidal continuously variable transmission, comprising:an inner race for transmitting power between an input disk and an output disk via an oil film, an outer race supported by a power roller support member, and a thrust ball bearing for supporting the inner race on the outer race such that the inner race is free to rotate, wherein the thrust ball bearing has an inner race groove having an arc-shaped cross-section formed in the inner race, and an outer race groove having an arc-shaped cross-section formed in the outer race, an annular space defined by the inner race groove and outer race groove, plural balls disposed in the annular space, and a holder for supporting the balls, wherein a first spin occurs in the contact part between each of the balls and the inner race groove which is the slip between each of the balls and inner race groove, wherein each of the balls and the inner race groove rotate relative to each other, and a second spin occurs in the contact part between each of the balls and the outer race groove which is the slip between each of the balls and the outer race groove, wherein each of the balls and outer race groove rotate relative to each other, and wherein the inner race groove has a radius of curvature less than the radius of curvature of the outer race groove, and a pitch diameter less than the pitch diameter of the outer race groove such that the direction of the rotation axis of the balls, defined by the balance between the frictional moment of the first spin and the frictional moment of the second spin, is set to a direction in which the angular velocity of the first spin is less than the angular velocity of the second spin.