| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotation drive unit which can enhance the concentricity of inner teeth constituting a reduction gear and a motor shaft of a motor.SOLUTION: A first inner bearing 46 constituting a reduction gear 40 is one member which is formed of an inner tooth part 71, a shaft support part 72 and a flange part 73, and is different from a first housing 15. The inner tooth part 71 forms inner teeth 74 which are engaged with a first planetary gear 47. The shaft support part 72 has an eleventh cylinder face 76 for supporting a motor shaft 32. The inner teeth 74 are located concentrically with the eleventh cylinder face 76. The inner teeth 74 of the first inner bearing 46 and the shaft support part 72 form one portion formed of the same members, and are relatively easy in accurately constituting mutual positional relationships. Accordingly, by accurately forming the first inner bearing 46, the concentricity of the inner teeth 74 of the first inner bearing 46 and the motor shaft 32 of the motor 30 can be enhanced. |
