Toroidal-type continuously variable transmission

A toroidal-type continuously variable transmission, comprising:

• an input shaft rotatably supported;
• an input side disk rotatable together with said input shaft and including an inner surface formed as a concave surface having an arc-shaped section;
• an output side disk including an inner surface formed as a concave surface having an arc-shaped section, said output side disk being disposed concentrically with said input side disk in such a manner that said inner surface thereof is opposed to said inner surface of said input side disk;
• a plurality of trunnions respectively swingable about their associated pivot shafts disposed at twisted positions to said input shaft;
• a plurality of shift shafts respectively supported on said trunnions;
• a plurality of power rollers each including a peripheral surface formed as a spherical-shaped convex surface, said power rollers being rotatably supported on the peripheries of said shift shafts while they are disposed on the inner surfaces of said trunnions and are also interposed between and held by said input side and output side disks;
• and,
• a plurality of thrust rolling bearings respectively interposed between the outer peripheral surfaces of said power rollers and the inner surfaces of said trunnions for supporting thrust loads to be applied to said power rollers,
• wherein each of said thrust rolling bearings including:
• an inner ring raceway formed in the outer peripheral surface of said power roller;
• and
• an outer ring disposed inside said trunnion and having an outer ring raceway, wherein said outer ring is made of high carbon chromium bearing steel, including a carbon content in a range of 0.95% to 1.10%, and is carbonitrided.