GEAR DEVICE FOR WATCH

摘要

PURPOSE:To eliminate troubles due to burrs by containing the burrs into a space formed by the end of a shaft and the outer circumference of the bottom of a shaft hole. CONSTITUTION:A semispherical shell-shaped convex section 3 is provided in the center of the end of a shaft 2 of a gear 1 molded with a resin such as nylon. A burr 4 is produced projecting on the mating surface with the die. On the other hand, a shaft hole 5a is formed in a box body 5 molded with a resin in such a manner as to be sunk like a cone in the periphery thereof. This allows the burr to develop on the end of the shaft at a somewhat inner position as illustrated so as to avoid interference with the bottom of the shaft hole 5a and the surrounding area thereof thereby preventing possible troubles by the burr 4.