| 摘要 |
PURPOSE:To surely prevent a gear from falling off with simple structure by elastically deforming elastic claws integratedly formed with the gear to fit the gear on a shaft, and moving the gear in the axial direction to engage the elastic claws with an engagement groove of the shaft. CONSTITUTION:In order to fit a gear G on a shaft S, the shaft S is inserted into a shaft insertion hole 12 of the gear G. Even after click parts 22 of elastic claws 2 integratedly formed with the gear G are brought into contact with an end 5 of the shaft S, the shaft S is further pushed into the gear G to be inserted along guide faces 22a of the click parts 22 and consequently a pair of elastic claws 2 are elastically deformed outward in the radial direction of the shaft G to be expanded, thus conducting insertion of the shaft S into the gear G. When an engagement groove 3 provided on the shaft S coincides with click parts 22 of the elastic claws 2 deformed outward in the radial direction, the click parts 22 are elastically restored inward in the radial direction of the shaft S to be engaged with the engagement groove 3 so that falling off of the gear G from the shaft S can be prevented. In order to detach the gear G, the elastic claws 2 are elastically deformed outward. |
