| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that, in a conventional power transmission device, when an engagement pin intrudes into a penetration hole due to vibration at a start of an engine, an engagement state of a pinion gear and an output gear is changed, stress corresponding to the output gear is thereby excessively generated, and there occurs such as malfunction that an output gear tooth of the output gear is broken and a durability life of the output gear is deteriorated.SOLUTION: A coupling unit comprises an output gear 6, a coupling 7, a rubber cushion 8 and the like. At a second rotating shaft part 61 of the coupling 7, there is arranged an elastic protrusion 91 which is elastically deformed into the inside of the second rotating shaft part 61 in a radial direction in the vicinity of a depth side of a recessed groove 81 when passing through the recessed groove 81 of a penetration hole 55, elastically recovered after passing through the penetration hole 55, and locked to a locking part 87 of the output gear 6 so as to be non-lockable. By this constitution, the come-off of the elastic protrusion 91 from the locking part 87 and an inclination of the output gear 6 caused by the lack of the rigidity of the second rotating shape part 61 can be eliminated. |
