| 摘要 |
PURPOSE:To reduce the outer diameter of a back of the watch case, by providing a stage part for engaging the back to a middle and ensuring the bayonet engage between the middle and the back. CONSTITUTION:A middle 1 has a positioning stage part 1a for a supporting ring 3 at its upper part, and a back engaging part 1b having substantially equal inner diameter to the part 1a protrudes on the case body 1. The middle 1 and the back 2 are fixed to each other by the bayonet engage method through the insertion and turning action. In such constitution, the outer diameter of the cover 2 can be reduced compared with the middle when the back is pressed and fixed to the side wall of the middle. |
