Patent ID: 7566285
Filing Date: 2009-07-28
Classification: F16H

Abstract:
1. A power train of an automatic transmission, comprising: an input shaft; an output gear; a transmission case; a speed reduction unit comprising a fixed input member that is fixedly connected to the input shaft, first and second variably stopped members that are variably connected to the transmission case, and a reduced speed output member that outputs first and second reduced rotational speeds; an output unit comprising a first variable input member that is fixedly connected to the reduced speed output member and is variably connected to the input shaft, a second variable input member that is variably connected to the input shaft, third and fourth variably stopped members that are variably connected to the transmission case, a shift speed output member that always acts as an output member by being fixedly connected to the output gear, wherein the output unit generates seven forward speeds and three reverse speeds at the shift speed output member by operations of the first and second variable input members and the third and fourth variably stopped members; a first clutch for variably connecting the first variable input member to the input shaft; a second clutch for variably connecting the second variable input member to the input shaft; a first brake for variably stopping the third variably stopped member; a second brake for variably stopping the first variably stopped member; a third brake for variably stopping the second variably stopped member; and a fourth brake for variably stopping the fourth variably stopped member.