| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent generation of abnormal sound in a torque limitter mechanism by providing an elastic member to press a joint on a worm shaft or a motor shaft between at least one of a pair of the joints and the worm shaft to be engaged with it or the motor shaft. SOLUTION: Annular grooves 23, 24 decentered from centers of joints 16, 17 are respectively formed on a lower end part of an inner peripheral surface of the joint 16 and an upper end part of an inner peripheral surface of the joint 17 on a device to transmit motive force by frictionally engaging the joints 16, 17 spline-connected to a worm shaft 6 and a motor shaft 14 by energizing force of a plate spring 19 provided in the inside of a cover 18. Thereafter, O rings 25, 26 are fitted in each of the annular grooves 23, 24 as elastic members. At this time, each of the O rings 25, 26 is devised to be crashed in narrow parts of the annular grooves 23, 24 but hardly to be crashed in wide parts of the annular grooves 23, 24, and the joints 16, 17 are limited from moving in the axial direction by energizing force of these O rings 23, 24.</p> |
