To form a cylinder parts provided with outer peripheral tooth having almost fixed thickness of a tooth-form by thickening the outer peripheral part of a disk-like stock, thereafter, bending the thickened part to one side part by a curling work and executing a tooth cutting work.
The outer periphery of the disk-like stock A is subjected to a roller working by a initial stage thickening roller R1 having narrow roller groove angle and successively, by a second thickening roller R2 having a little wider roller groove angle. After forming the annular thickened part on the outer periphery of the disk-like stock A, the curling work is executed with a curling roller K to form an intermediate formed material E of a cylinder part having projecting thickened part at the one side. Successively, a backup roller U regulating tooth width is provided at the position where the thickened cylinder part of the intermediate formed material E is confronted to a tooth- forming roller F to form the outer periphery of the prescribed tooth-form by being pressurized by the tooth-forming roller F.
AKIYOSHI HIDEYASU
MURATA SHIGEO
NIPPON SPINDLE MFG CO LTD