To provide a technique for working a shaft body having highly accurate minute grooves, which technique can accomplish the densification and the mass production of the shaft body, and further to provide the shaft body.
Metallic particles of stainless steel are mixed and kneaded with bonding material, such as polyethylene. The kneaded material is injected from an injection molding machine to form a shaft body blank and degreased and sintered. Minute herringbone shape grooves are formed by a rolling operation carried out on the working surface of the degreased and sintered shaft body blank by means of a rolling apparatus in such a way of gripping the shaft body blank by means of two rolling dies and pressing the shaft body blank while turning it by relatively moving them.
COPYRIGHT: (C)2008,JPO&INPIT
TAKEMASU MITSUIE
AMANO SHUICHI
Sadao Enjoji