| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a gear member which requires no machining and can be manufactured inexpensively, and a method of and a device for forming a tooth shape capable of forming a tooth part of the gear member so as to have a desired shape by coining processing. <P>SOLUTION: In coining processing of a tooth part 3 of a processing object 1 which is preformed by punching a tabular steel plate, a press member 14 is first come into press-contact with the processing object 1 placed on a base 12 of a tooth shape-forming device 11 in a region except for the periphery including the tooth part 3 to chuck the processing object 1 by the base 12 and the press member 14. During the chucking, a groove 5 is engraved by a ridge 12a of the base 12 so that the groove extends in an arc shape along the arranging direction of the tooth part 3 on the surface of the processing object 1. The groove 5 is located slightly inner circumferential side with respect to the portion where the inner circumferential edge 15a of the coining punch 15 abuts, and functions as a flow-stopping portion inhibiting plastic flow during the coining processing. <P>COPYRIGHT: (C)2012,JPO&INPIT |
