Patent ID: 7632206

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, third and fourth planetary gear sets (P 1 , P 2 , P 3 , P 4 ), each of the first, the second, the third and the fourth planetary gear sets (P 1 , P 2 , P 3 , P 4 ) comprising a sun gear, a carrier and a ring gear; at least third, fourth, fifth, sixth and seventh rotatable shafts ( 3 , 4 , 5 , 6 , 7 ), as well as at least six shifting elements ( 03 , 04 , 05 , 14 , 17 , 27 , 35 , 47 ), comprising first, second and third brakes ( 03 , 04 , 05 ) and first, second and third clutches ( 14 , 17 , 27 , 35 , 47 ) whose selective engagement creates different gear ratios between the input shaft ( 1 ) and the output shaft ( 2 ) so that at least first, second, third, fourth, fifth, sixth, seventh, eighth and ninth forward gears and one 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 the sun gear of the third planetary gear set (P 3 ); the output shaft ( 2 ) is permanently connected to the ring gear of the fourth planetary gear set (P 4 ); the third shaft ( 3 ) is permanently connected to the carrier of the second planetary gear set (P 2 ), and the third shaft ( 3 ) is detachably coupled, via the first brake ( 03 ), to the housing (G), and, via the third clutch ( 35 ), to the fifth shaft ( 5 ); the fourth shaft ( 4 ) is permanently connected to the ring gear of the third planetary gear set (P 3 ) and the carrier of the fourth planetary gear set (P 4 ), and detachably connected, via the second brake ( 04 ), to the housing (G); the fifth shaft ( 5 ) is permanently connected to the ring gear of the first planetary gear set (P 1 ) and detachably connected, via the third brake ( 05 ), to the housing (G); the sixth shaft ( 6 ) is permanently connected to the carrier of the first planetary gear set (P 1 ), the ring gear of the second planetary gear set (P 2 ), and the sun gear of the fourth planetary gear set (P 4 ); the seventh shaft ( 7 ) is permanently connected to the carrier of the third planetary gear set (P 3 ) and detachably connected, via the second clutch ( 27 ), to the output shaft ( 2 ); an eighth shaft ( 0 ) is permanently connected to the sun gear of the first planetary gear set (P 1 ) and the housing (G); and one of the first shaft ( 1 ) is detachably connected, via the first clutch ( 14 ), to the fourth shaft ( 4 ), the input shaft ( 1 ) is detachably connected, via the first clutch ( 17 ), to the seventh shaft ( 7 ), and the fourth shaft ( 4 ) is detachably connected, via the first clutch ( 47 ), to the seventh shaft ( 7 ).