Patent ID: 9328811
Filing Date: 2016-05-03
CPC Classification: B21D,C21D,C22C,C23C,F16H,Y10T

Claim Text:
1. A drive plate comprising: a disk-shaped plate portion; and a tooth-shaped portion formed at an outer peripheral end of the plate portion, wherein: the plate portion and the tooth-shaped portion are integrally shaped from a single steel plate material; the plate portion and the tooth-shaped portion include a carburized layer provided over an entire surface layer of the plate portion and the tooth-shaped portion, the carburized layer having a carbon concentration higher than that of a center portion of the plate portion and the tooth-shaped portion in a thickness direction; the carburized layer of the plate portion is higher in hardness than the center portion of the plate portion in the thickness direction; and the carburized layer of the tooth-shaped portion has been subjected to a quenching process, and is further higher in hardness than the carburized layer of the plate portion, wherein the center portion of the plate portion in the thickness direction has a ferrite structure, the carburized layer of the plate portion has a pearlite structure, and the carburized layer of the tooth-shaped portion has a martensite structure.