Patent ID: 8257215

Claim:
A multi-speed planetary coupling transmission ( 3 ) comprising: a transmission input shaft ( 7 ) and a transmission output shaft ( 8 ), the transmission input shaft ( 7 ) being functionally connected to an internal combustion engine ( 2 ); first, second and third planetary gear sets ( 4 , 5 , 6 ), each of the first, the second and the third planetary gear sets ( 4 , 5 , 6 ) having a sun gear, a planetary carrier and a ring gear; first, second, third and fourth shifting elements (A, B, D, E) which are actuatable to implement various gear ratios in the multi-speed planetary coupling transmission ( 3 ); a first electric machine (EM 1 ) having a stator ( 11 ) and a rotor ( 10 ), the stator ( 11 ) being fixed to a housing ( 9 ) and the rotor ( 10 ) being fixed to the ring gear ( 6 B) of the third planetary gear set ( 6 ) such that torque generated by the first electric machine (EM 1 ) either supports torque generated by the internal combustion engine ( 2 ) to achieve at least one of the various gear ratios, or is utilized in a starting operation; the sun gear of the first planetary gear set ( 4 ) is rotationally fixed to the transmission input shaft ( 7 ), and the planetary carrier ( 4 A) of the first planetary gear set ( 4 ) is rotationally fixed to the ring gear ( 5 B) of the second planetary gear set ( 5 ); the sun gear ( 5 C) of the second planetary gear set ( 5 ) is rotationally fixed to the sun gear ( 6 C) of the third planetary gear set ( 6 ), and the planetary carrier ( 5 A) of the second planetary gear set ( 5 ) is rotationally fixed to the ring gear ( 6 B) of the third planetary gear set ( 6 ); and the planetary carrier ( 6 A) of the third planetary gear set ( 6 ) is rotationally fixed to the transmission output shaft ( 8 ).