| 摘要 |
PURPOSE:To lessen backlash and reduce wear of teeth of a gear by providing each gear with a cylinder which are united in a body and brought into engagement by pressing means. CONSTITUTION:A drive gear 6 and a reduction gear 7 are provided with cylinders 16, 18 concentric with the gears 6, 7, the sum of each radius of which is the sum of each pitch radius of the gears 6, 7 which engage each other. A leaf spring 20 is adapted to press one gear against the other gear to engage each other. When the drive gear 6 and the reduction gear 7 are rotated, smoothness of such rotation is ensured, resisting the leaf spring 20, but when the gears 6, 7 are stopped, pressure force of the leaf spring 20 causes cylindrical surfaces 15, 17 of the cylinders 16, 18 to contact each other, resulting in that the distance between a motor shaft 5 and a support shaft 8 is the sum of each pitch radius of the gears 6, 7. Accordingly, backlash is produced only by dimensions error between pitch circles of the drive gear 6 and the reduction gear 7 and the cylindrical surfaces 15, 17. |
