Vehicular automatic transmission

摘要

The present invention is intended to reduce the weight and size of a speed-change mechanism by shortening a high-torque transmission system and to attenuate speed-change shock by reducing an inertia torque in a multi-stage vehicular automatic transmission. For this purpose, a vehicular automatic transmission is equipped with a planetary gear set that receives a decelerated rotation and a non-decelerated rotation as inputs and outputs a plurality of speed-change rotations, a reduction planetary gear, an input shaft that passes through an inner side of the planetary gear set, first and third clutches that couple the input shaft to two different speed-change elements of the planetary gear set respectively through the reduction planetary gear in an engageable and disengageable manner, and a second clutch that couples the input shaft to the other speed-change element of the planetary gear set in an engageable and disengageable manner. The reduction planetary gear and the third clutch for transmitting a high torque are arranged on one side of the planetary gear set, whereas the first clutch for transmitting a high torque is arranged on the other side of the planetary gear set. <IMAGE>