MANUFACTURE OF MEMBER WITH TOOTH FORM ON CIRCUMFERENCE

PURPOSE: To manufacture a member with a tooth form on the circumference in a short period of time with improved productivity by producing a circumferential thick part by means of spinning on a disk shaped blank and forming a tooth form on the circumference by means of forging press. CONSTITUTION: Spinning is performed on the outer peripheral part of a disk shaped blank 1 to form a circumferential thick part 1a. The disk shaped blank 1 is set on a forging press machine 2, an upper punch 3 of which is lowered while holding in the planar part 1b of the disk shaped blank 1, is further lowered. A tooth form is gradually formed on the circumferential thick part 1a by means of the tooth forming part 3a of the upper punch 3 and the taper- shaped tooth forming part 4a of a die 4. The circumferential thick part 1a is put into a tooth forming part 4b and formed into a desired tooth form. Thus, no deformation is produced because no welding is used. In addition, without form rolling for the tooth form, working is completed in a short period of time.