Method of manufacturing a tappet in an internal combustion engine

摘要

A method of manufacturing a tappet which is used in an internal combustion engine of vehicles is provided. A core material of the tappet has a helical groove on the outer circumferential surface, and a wear resistant coating layer, the ends of which are chamfered. In the vicinity of the end of the core material the helical groove gradually becomes small toward the end, thereby preventing peaks of the helical groove from exposure to the outside.