| 摘要 |
PURPOSE:To eliminate or reduce the noises upon start and stop by bringing one of larger and smaller gears under its stopped condition into engagement with a pin- shaped elastic gear which standing in the axial direction of the other gear. CONSTITUTION:A rotor wheel pinion 13 of a smaller gear is composed of a tooth portion 13a having a normal tooth shape and an elastic tooth portion 13c formed in a tooth-removed portion 13b. The tooth-removed portion 13b has its two teeth removed at the tooth portion 13a each step angle (e.g., 180 degrees) of a rotor. The tooth portion 13c is formed at a position corresponding to the tooth-removed tooth portion so that it engages with the tooth portion 20a of a second wheel 20 or a larger gear under the rotation stop condition. On the other hand, the tooth portion 13c absorbs the shocks upon the start and stop condition of the rotor 10 and is set to fail to engage with the second wheel 20 during the rotations of the rotor 10. As a result, the shocks acted upon the inter-gears between the wheel pinion 13 and the second wheel 20 during the stop are absorbed by the elastic tooth portion 13c so that the noises can be remarkably eliminated or removed. |
