Patent ID: 7892137

Claim:
A automatic multi-speed transmission of a planetary design for a motor vehicle, the transmission comprising: an input shaft (AN) and an output shaft (AB); first, second, third and fourth planetary gearsets (RS 1 , RS 2 , RS 3 , RS 4 ), each of the first planetary gearset (RS 1 ), the second planetary gearset (RS 2 ), the third planetary gearset (RS 3 ) and the fourth planetary gearset (RS 4 ) comprise a sun gear, a planet carrier and a ring gear; at least first, second, third, fourth, fifth, sixth, seventh and eighth rotatable shafts ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ) and first, second, third, fourth and fifth shifting elements (A, B, C, D, E) whose selective engagement defines different gear ratios between the input shaft (AN) and the output shaft (AB) such that eight forward gears and at least one reverse gear are implemented; wherein the carrier (ST 4 ) of the fourth planetary gearset (RS 4 ) and the input shaft (AN) are coupled and form the first shaft ( 1 ); the carrier (ST 3 ) of the third planetary gearset (RS 3 ) and the output shaft (AB) are coupled and form the second shaft ( 2 ); the sun gear (SO 1 ) of the first planetary gearset (RS 1 ) and the sun gear (SO 4 ) of the fourth planetary gearset (RS 4 ) are coupled and form the third shaft ( 3 ); the ring gear (HO 1 ) of the first planetary gearset (RS 1 ) forms the fourth shaft ( 4 ); the carrier (ST 2 ) of the second planetary gearset (RS 2 ) and the sun gear (SO 3 ) of the third planetary gearset (RS 3 ) are coupled and form the fifth shaft ( 5 ); the carrier (ST 1 ) of the first planetary gearset (RS 1 ) and the ring gear (HO 3 ) of the third planetary gearset (RS 3 )are coupled and form the sixth shaft ( 6 ); the sun gear (SO 2 ) of the second planetary gearset (RS 2 ) and the ring gear (HO 4 ) of the fourth planetary gearset (RS 4 ) are coupled and form the seventh shaft ( 7 ); the ring gear (HO 2 ) of the second planetary gearset (RS 2 ) forms the eight shaft ( 8 ); the first shifting element (A) is arranged between the third shaft ( 3 ) and a transmission housing (GG); the second shifting element (B) is arranged between the fourth shaft ( 4 ) and the transmission housing (GG); the third shifting element (C) is arranged within a power flow between the first shaft ( 1 ) and the fifth shaft ( 5 ); the fourth shifting element (D) is arranged within the power flow between one of the second shaft ( 2 ) and the eighth shaft ( 8 ) and the sixth shaft ( 6 ) and the eighth shaft ( 8 ); and the fifth shifting element (E) is arranged within the power flow between one of the fifth shaft ( 5 ) and the seventh shaft ( 7 ), the fifth shaft ( 5 ) and the eighth shaft ( 8 ) and the seventh shaft ( 7 ) and the eighth shaft ( 8 ).