| 摘要 |
PURPOSE:To enable a watch wheel to be manufactured only the by plasric work and promote mass production and cost down, by providing a hole in the center of a flat plate-shaped root part further integrally forming a gear part swelling on the root part in a range including a plane. CONSTITUTION:When a wheel is manufactured, first a coining process, pressurizing a belt material 5 by a bottom die 13 having a flat shaped upper surfce and an upper sie 14 forming a tooth-shaped recessed part 15, molds a tooth profile 8 in a root part 6 reducing its material thickness. Next a shearing process shears the external shape of a gear between a die 17 and a punch 16 by lifting the punch 16. Simultaneously, the process, punching a center hole by a punching arrow 18 fixed to the die 17, drops a punching chip through a center hole 19 of the punch 16. And the watch wheel 11, having a hole 12 in the center of the root part 6 similarly integrally forming a gear part in the periphery, is completed. In this way, the watch wheel 11 can be presented only by plastic work. |
