| 摘要 |
PURPOSE:To facilitate control by enhancing stop accuracy when the moving speed fluctuates and also when the operating voltage of drive motor fluctuates considerably. CONSTITUTION:Drive force is transmitted from a motor 39 through a worm wheel reduction gear 13 and a planetary reduction gear 14 to an output shaft 20 mounting a fixed ring 21. First and second brake shoes 22, 23, operating alternately, are mounted on the differential shaft of the planetary reduction gear 14, i.e., a large sun gear 19, and the fixed ring 21, respectively, so that the first brake shoe 22 restricts or release the large sun gear 19, respectively, upon motion or stoppage of an electric apparatus. |
