Patent ID: 8485934

Claim:
A multi-ratio transmission of planetary design for a motor vehicle, the multi-ratio transmission comprising: a drive input shaft ( 1 ) and a drive output shaft ( 2 ); first, second, third and fourth planetary gearsets (P 1 , P 2 , P 3 , P 4 ) arranged in a housing (G) of the transmission, each of the first planetary gearset (P 1 ), the second planetary gearset (P 2 ), the third planetary gearset (P 3 ) and the fourth planetary gearset (P 4 ) comprising a sun gear, a planet carrier and a ring gear; third, fourth, fifth, sixth, seventh and eighth rotary shafts ( 3 , 4 , 5 , 6 , 7 , 8 , 8 ′) at least six shifting elements comprising first and second brakes ( 03 , 04 ) and first, second, third and fourth clutches ( 13 , 16 , 18 , 48 , 67 ) and selective engagement the first brake ( 03 ), the second brake ( 04 ), the first clutch ( 13 ), the second clutch ( 16 ), the third clutch ( 67 ) and the fourth clutch ( 18 , 48 ) results in various gear ratios between the drive input shaft ( 1 ) and the drive output shaft ( 2 ) such that first, second, third, fourth, fifth, sixth, seventh, eighth and ninth forward gears and one reverse gear can be implemented; the sun gear of the first planetary gearset (P 1 ) is functionally connected to the drive input shaft ( 1 ) and the drive input shaft ( 1 ) is connectable, via the first clutch ( 13 ), to the third shaft ( 3 ) and, via the second clutch ( 16 ), to the sixth shaft ( 6 ); the third shaft ( 3 ) is coupled to the planet carrier of the second planetary gearset (P 2 ) and the ring gear of the third planetary gearset (P 3 ) and is connectable, via the first brake ( 03 ), to the housing (G) of the transmission; the fourth shaft ( 4 ) is connectable, via the second brake ( 04 ), to the housing (G) of the transmission and is functionally connected to the ring gear of the second planetary gearset (P 2 ) and the planet carrier of the first planetary gearset (P 1 ); the sixth shaft ( 6 ) is coupled to the sun gear of the fourth planetary gearset (P 4 ) and is connectable, via the third clutch ( 67 ), to the seventh shaft ( 7 ); the seventh shaft ( 7 ) is coupled to the sun gear of the third planetary gearset (P 3 ) and the sun gear of the second planetary gearset (P 2 ); the ring gear of the first planetary gearset (P 1 ) is fixedly connected to the housing (G) of the transmission; the fifth shaft ( 5 ) is coupled to the planet carrier of the third planetary gearset (P 3 ) and the ring gear of the fourth planetary gearset (P 4 ); and the drive output shaft ( 2 ) is coupled to the planet carrier of the fourth planetary gearset (P 4 ).