| 摘要 |
PROBLEM TO BE SOLVED: To accurately center a carrier of a planetary gear mechanism, with simple structure.SOLUTION: A planetary gear mechanism 37 includes an annular carrier holding member 74 fixed on fixing parts 42, 61, and a fine gap α filled with grease is interposed between an inner circumferential surface of the carrier holding member 74 and an outer circumferential surface 63b of a carrier 63, so that the carrier 63 can be centered on the fixing parts 42, 61. Since the planetary gear mechanism 37 includes bolts 75 for regulating rotation of the carrier holding member 74 against the fixing parts 42, 61 and bolt holes 74b which is formed in the carrier holding member 74 and with which the bolts 75 are loosely engaged, the thickness of the gap α is uniformed in a circumference direction by viscosity of grease in a loose engagement between the bolts 75 and the bolt holes 74b and the carrier holding member 74 are fixed with the bolts 75 in the uniform thickness state of the gap α, so that highly accurate centering of the carrier 63 can be achieved. |
