| 摘要 |
PROBLEM TO BE SOLVED: To provide a reduction gear and a transmission ratio variable steering system capable of reducing a length of a pair of input and output rotating members in a rotating axis direction compared to the conventional one. SOLUTION: In this reduction gear 20, a region between an input side rotating base 31 and an output side rotating base 32 is surrounded by a rotor 45 of a cylindrical motor 43, and an inner race 50B of a bearing 50 disposed in an inner side of the rotor 45 is rotatable around a second rotating axis X2 obliquely crossing a first rotating axis X1. Relay gears 41G and 42G meshed with an input side gear 31G and an output side gear 32G and integrally rotated are provided on both side parts of the inner race 50B in a back-to-back state. The motor 43 as a driving source of the relay gears 41G and 42G is arranged on the side parts of the relay gears 41G and 42G in such a manner of surrounding the region between the input side rotating base 31 and the output side rotating base 32, and thereby, the length in the direction of the first rotating axis X1 can be shorter than the conventional one. COPYRIGHT: (C)2010,JPO&INPIT |
