| 摘要 |
PURPOSE:To simplify the structure of a speed reducer and make it compact, by providing two bevel gears engaged with each other at the inner ends of an input and an output shafts and by changing the number of the teeth of the bevel gears to obtain a desired speed reduction ratio. CONSTITUTION:A gear shaft 5 is provided at the inner end of an input shaft 3 so that the gear shaft 5 has an axis 5L crossed at an inclination angle of theta with that 3L of the input shaft 3. A first bevel gear 7 is mounted on the gear shaft 5 so that they have the same axis 5L. A second bevel gear 15, which is engaged with the first bevel gear 7 and differs in the number of teeth from it, is mounted on the inner end of an output shaft 13 which has the axis 3L. When the input shaft 3 is rotated, the gear shaft 5 is turned relative to the first bevel gear 7 and the bevel gears 7, 15 perform precessional swinging while being engaged with each other. At that time, the engaging pin 9 of the first bevel gear 7 is reciprocated in the engaging hole 10 of a machine body 1. As a result, torque is transmitted to the output shaft 13 with a desired speed reduction ratio depending on the difference between the numbers of the teeth of the bevel gears 7, 15. |
