Patent ID: 7645207

Claim:
A multi-speed automatic transmission of a planetary design for a motor vehicle, the transmission comprising: a drive shaft (AN) and an output shaft (AB); first, second, third, and fourth planetary gearsets (RS 1 , RS 2 , RS 3 , RS 4 ), and each of the first, the second, the third, and the fourth planetary gearsets (RS 1 , RS 2 , RS 3 , RS 4 ) comprises a sun gear, a 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 creates different gear ratios between the drive shaft (AN) and the output shaft (AB) so that eight forward gears and a reverse gear can be implemented; wherein the carrier (ST 4 ) of the fourth planetary gearset (RS 4 ) and the drive shaft (AN) are coupled with one another and form the first shaft ( 1 ); 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 with one another and form the third shaft ( 3 ); the ring gear (HO 2 ) of the second planetary gearset (RS 2 ), the carrier (ST 3 ) of the third planetary gearset (RS 3 ) and the output shaft (AB) are coupled with one another and form the second shaft ( 2 ); the carrier (ST 1 ) of the first planetary gearset (RS 1 ) forms the fourth shaft ( 4 ); the sun gear (SO 3 ) of the third planetary gear shaft (RS 3 ) forms the fifth shaft ( 5 ); the ring gear (HO 1 ) of the first planetary gearset (RS 1 ), the carrier (ST 2 ) of the second planetary gearset (RS 2 ) and the ring gear (HO 3 ) of the third planetary gearset (RS 3 ) are coupled with one another and form the sixth shaft ( 6 ); the ring gear (HO 4 ) of the fourth planetary gearset (RS 4 ) forms the seventh shaft ( 7 ); the sun gear (SO 2 ) of the second planetary gearset (RS 2 ) forms the eighth shaft ( 8 ); the first shifting element (A) is located between the third shaft ( 3 ) and a gearbox housing (GG); the second shifting element (B) is located between the fourth shaft ( 4 ) and the gearbox housing (GG); the third shifting element (C) is located, in a direction of power flow, between the first shaft ( 1 ) and the fifth shaft ( 5 ); the fourth shifting element (D) is located, in the direction of power flow, between the seventh ( 7 ) shaft and the eighth shaft ( 8 ); and the fifth shifting element (E) is located, in the direction of power flow, between the fifth shaft ( 5 ) and the seventh shaft ( 7 ).