Patent ID: 7455614
Filing Date: 2008-11-25
Classification: F16H

Abstract:
1. A power train of an automatic transmission, comprising: a first planetary gear set having operating members of a first sun gear, a first ring gear, and a first planet carrier; a second planetary gear set having operating members of a second sun gear, a second ring gear, and a second planet carrier; a third planetary gear set having operating members of a third sun gear, a short-pinion-side ring gear, a long-pinion-side ring gear, and a third planet carrier; an input shaft; an output gear; and a transmission case, wherein the third planet carrier is fixedly connected to the first ring gear, the second ring gear is fixedly connected to the first planet carrier, the long-pinion-side ring gear always acts as an input element by being fixedly connected to the input shaft, the second planet carrier always acts as an output element by being fixedly connected to the output gear, the second ring gear is variably connected to the input shaft via a first clutch, the first sun gear is variably connected to the first planet carrier via a second clutch, the second sun gear is variably connected to the first sun gear via a third clutch, the short-pinion-side ring gear is variably connected to the transmission case via a first brake and is subjected to a stopping operation of the first brake, at least one of the variably connected first sun gear and the second sun gear is variably connected to the transmission case via a second brake and is subjected to a stopping operation of the second brake, the third sun gear is variably connected to the transmission case via a third brake and is subjected to a stopping operation of the third brake, and the first planet carrier is variably connected to the transmission case via a fourth brake and is subjected to a stopping operation of the fourth brake.