| 摘要 |
PURPOSE:To increase the reduction ratio with a simple structure without magnification of the device and prevent the operational structure for the opening and closing device from moving due to the torque from the output shaft. CONSTITUTION:Asymmetrical lead grooves 7a, 7b having respective lead angles are formed at the circumferential symmetrical face and a cylinder 8 firmly stuck to a frame 1 is provided. An output shaft 2 rotatably held on the frame 1 is also provided. A sliding deformed pipe 3 fitted to the inside of the output shaft 2 so as to be axially movable and regulated in the rotary direction is arranged. A vertically movable body 4 having a female screw 4a at the center is fitted. Rollers 5a, 5b attached at both ends of the vertically movable body 4 and fitted in the lead grooves 7a, 7b of the cylinder 8 respectively are provided. And further, an input screw bar 9 having a male screw 9a engaging with the female screw 4a of the body 4 and driven by a motor 11 is provided. |
