| 摘要 |
PURPOSE:To enable miniaturization of a thrust bearing and to contrive shortening of length of a speed change gear in its axial direction, by making a device into such a structure that thrusts which are generated from a ring gear and a sun gear at the time of power transmission of a planetary gear and are in the opposite direction are offset each other. CONSTITUTION:A speed change gear 2 includes a first and a second planetary gear systems 23 and 24 provided on the rear and the front of an intermediate branch wall 63 of a transmission case 6. In this instance, as for the second system 24, a thrust bearing 81 is interposed between a ring gear 242 and a carrier 241, and a thrust bearing 32 is interposed between the carrier 241 and a second intermediate part 27 with which a sun gear 243 is formed in a body. On the other hand, as for the first system 23, thrust bearings 84, 86 and 87 are interposed between a ring gear 233 and an inner race 29, a carrier 232 and the ring gear 233 and the carrier 232 and a sun gear 231 respectively. With this, thrust loads relatively in the opposite direction can be cancelled each other. |
