Patent ID: 7637838

Claim:
A multi-speed automatic transmission of a planetary design for a motor vehicle, the transmission comprising: an input shaft ( 1 ) and an output shaft ( 2 ) arranged in a housing (G); first, second and third planetary gear sets (P 1 , P 2 , P 3 ), and each of the first, the second and the third planetary gear sets (P 1 , P 2 , P 3 ) comprising a sun gear, a carrier and a ring gear; at least third, fourth, fifth and sixth rotatable shafts ( 3 , 4 , 5 , 6 ) as well as six control elements ( 03 , 04 , 05 , 15 35 , 36 , 45 , 46 ), comprising first and second brakes ( 03 , 04 , 05 ) and first, second, third and fourth clutches ( 15 , 35 , 36 , 45 , 46 ), whose selective engagement of which creates different gear ratios between the input shaft ( 1 ) and the output shaft ( 2 ) so that at least first, second, third, fourth, fifth, sixth and seventh forward gears and a reverse gear can be implemented; wherein the input shaft ( 1 ) is permanently connected to the sun gear of the second planetary gear set (P 2 ) and is detachably connected, via the first clutch ( 15 ), to the fifth shaft ( 5 ); the output shaft ( 2 ) is permanently connected to the ring gear of the third planetary gear set (P 3 ); the third shaft ( 3 ) is permanently connected to the ring gear of the second planetary gear set (P 2 ) and the carrier of the first planetary gear set (P 1 ); the fourth shaft ( 4 ) is permanently connected to the carrier of the second planetary gear set (P 2 ), is detachably connected, via the second brake ( 04 ), to the housing (G) and, via the fourth clutch ( 46 ), to the sixth shaft ( 6 ); the fifth shaft ( 5 ) is permanently connected to the carrier of the third planetary gear set (P 3 ) and detachably connected, via the third clutch ( 45 ), to the fourth shaft ( 4 ); the sixth shaft ( 6 ) is permanently connected to the sun gear of the third planetary gear set (P 3 ) and the ring gear of the first planetary gear set (P 1 ); the sun gear of the first planetary gear set(P 1 ) is fixed to the housing (G); and one of: the fifth shaft ( 5 ) is detachably connected, via the first brake ( 05 ), to the housing (G) and the third shaft ( 3 ) is detachably connected, via the second clutch ( 36 ), to the sixth shaft ( 6 ); and the third shaft ( 3 ) is detachably connected, via the first brake ( 03 ), to the housing (G) and, via the second clutch ( 35 ), to the fifth shaft ( 5 ).