Patent ID: 8986153
Filing Date: 2015-03-24
Classification: F16H

Abstract:
1. A planetary gear train of an automatic transmission for vehicles, comprising: an input shaft adapted to receive engine torque; an output shaft adapted to output a shifted torque; a first planetary gear set outputting a negative rotation speed by using a rotation speed selectively input from the input shaft; a second planetary gear set outputting a reduced rotation speed by using the rotation speed selectively input from the input shaft or to selectively become a direct-coupling state together with the first planetary gear set; a compound planetary gear set having four rotation elements by combining a third and fourth planetary gear set, and changing the rotation speed selectively input from the input shaft through two paths and the negative rotation speed and the reduced rotation speed input respectively from the first and second planetary gear sets into nine forward speeds and one reverse speed and to output the nine forward speeds and the one reverse speed; seven rotational members including two rotation elements connected to each other or one rotation element among rotation elements of the first and second planetary gear sets and the four rotation elements of the compound planetary gear set; and six friction members including clutches interposed between a selected rotational member among the seven rotational members and the input shaft or between selected rotational members, and brakes interposed between a selected rotational member among the seven rotational members and a transmission housing.