Patent ID: 9316303
Filing Date: 2016-04-19
CPC Classification: F16C,F16H

Claim Text:
1. A planet roller speed changer comprising: an input shaft; a stationary ring disposed around the input shaft so as to be concentric with the input shaft; a plurality of cylindrical planet rollers that are in rolling contact with both the input shaft and the stationary ring; an output shaft; a carrier including a carrier main body fixed to the output shaft so as to be rotatable together with the output shaft, and a plurality of pins which extend from the carrier main body in a thrust direction, each of which is disposed in a corresponding one of the planet rollers, and each of which passes through the corresponding one of the planet rollers; and multiple pairs of first and second radial bearings, the first and second radial bearings in each of the multiple pairs being respectively disposed in two rows between an outer periphery of a corresponding one of the pins and an inner periphery of a corresponding one of the planet rollers so as to face each other in the thrust direction, and supporting the planet roller such that the planet roller is rotatable, wherein a first inner ring of each of the first radial bearings, the first radial bearing being farther from the carrier main body than a corresponding one of the second radial bearings, is fitted, by interference fit, onto a first region of the outer periphery of the pin, the first region being far from the carrier main body, a second inner ring of each of the second radial bearings, the second radial bearing being closer to the carrier main body than a corresponding one of the first radial bearings, is fitted, by clearance fit, onto a second region of the outer periphery of the pin, the second region being closer to the carrier main body than the first region, and the planet roller speed changer further comprises elastic members each of which is interposed between a corresponding one of the second radial bearings and the carrier main body, and elastically presses a corresponding one of the second inner rings in the thrust direction that is a direction away from the carrier main body.