Patent ID: 7878938
Filing Date: 2011-02-01
Classification: F16H

Abstract:
1. A power train of an automatic transmission, comprising: a speed reduction unit comprising a first operating member fixedly connected to a transmission case, a second operating member always receiving rotation speed of an input shaft, and a third operating member generating reduced rotation speed by operation of the first and second operating members; an output unit comprising a fourth operating member selectively receiving the reduced rotation speed from the third operating member or selectively connected to the transmission case, a fifth operating member selectively receiving the rotation speed of the input shaft, selectively receiving the reduced rotation speed from the third operating member, or selectively connected to the transmission case, a sixth operating member selectively connected to the transmission case, a seventh operating member selectively receiving the reduced rotation speed from the third operating member or selectively receiving the rotation speed of the input shaft, and an eighth operating member generating nine forward speeds and two reverse speeds by operation of the fourth, fifth, sixth, and seventh operating members; and a plurality of friction members selectively connecting the operating members of the speed reduction unit and the output unit to the input shaft, other operating members, or the transmission case therebetween; wherein the plurality of friction members comprise: