CAMSHAFT, METHOD OF MANUFACTURING CAM FOR CAMSHAFT, AND METHOD OF MANUFACTURING SHAFT FOR CAMSHAFT

摘要

A method of manufacturing a cam for a camshaft, comprising the steps of continuously applying, to a billet having a volume larger by a specified volume than a final product, a plurality of cold forging steps formed of a preliminary outline upsetting, an outline drawing, a simultaneous piercing of inner and outer diameter surfaces, a press-molding forming excess amount as burrs on the inner diameter surface, a piercing of the inner diameter surface for removing the burrs from the inner diameter surface, and a simultaneous ironing of the inner and outer diameter surfaces. The final finishing (machining) of a cam (profile) surface can be eliminated, and the final product of the cam for the camshaft having a high dimensional accuracy can be provided.