Patent ID: 6659909
Filing Date: 2003-12-09
Classification: C21D,F16H

Abstract:
A toroidal continuously variable transmission system comprising:an input disk and an output disk which have traction surfaces defined between a small-diameter portion and a large-diameter portion and having an arc-shaped concave section and which are coaxially arranged such that the traction surfaces face each other; and power rollers which are frictionally engaged with the traction surfaces of the input and output disks and transmit a driving force, wherein at least one of the input disk, the output disk and the power rollers is formed of an alloy steel which contains 0.15 to 2.0% by weight of Mo, which is subjected first to carbonitriding processing executed at a temperature not lower than 1,000Â° C. and then to hardening and tempering, and which has a surface carbon content of 0.8 to 1.4%, and at least one of the input disk, the output disk, a power roller of a power roller bearing and an outer ring thereof has a carbon content which falls within a range of 0.3 to 0.5%.