Patent ID: 9644713
Date: 2017-05-09
CPC Classifications: F16H

Claim:
1. A planetary gear train of an automatic transmission for a vehicle, the planetary gear train comprising: an input shaft receiving power from an engine; an output shaft outputting the power changed in speed; a first planetary gear set including a first sun gear, a first planet carrier, and a first ring gear; a second planetary gear set including a second sun gear, a second planet carrier, and a second ring gear; a third planetary gear set including a third sun gear, a third planet carrier, and a third ring gear; a fourth planetary gear set including a fourth sun gear, a fourth planet carrier, and a fourth ring gear; a first rotating shaft including the first sun gear; a second rotating shaft including the first planet carrier, the second ring gear, the third sun gear, and the fourth sun gear; a third rotating shaft including the first ring gear; a fourth rotating shaft including the second sun gear, and selectively connected with the first rotating shaft and simultaneously selectively connected with a transmission housing; a fifth rotating shaft including the second planet carrier, and selectively connected with the first rotating shaft and simultaneously directly connected with the input shaft; a sixth rotating shaft including the third planet carrier and the fourth ring gear, and selectively connected with the third rotating shaft and simultaneously selectively connected with the transmission housing; a seventh rotating shaft including the third ring gear, and selectively connected with the first rotating shaft; an eighth rotating shaft including the fourth planet carrier, and directly connected with the output shaft; and six friction elements disposed between the rotating shafts, and disposed at positions where the rotating shafts are selectively connected with the transmission housing.