Patent ID: 7682281

Claim:
A dual clutch planetary transmission ( 1 ) comprising: a first planetary gear set (P 1 ), a second planetary gear set (P 2 ) and a third planetary gear set (P 3 ), at least a first frictional shifting element (K 1 ) and a second frictional shifting element (K 2 ) for shifting to a desired one of various power paths in a power flow, and first, second, third, fourth, fifth and sixth shape-fit shifting elements (A to F) for attaining various ratio stages within the power paths, a housing ( 2 ), a transmission input shaft ( 3 ), and a transmission output shaft ( 4 ), wherein at least one of the first and the second frictional shifting elements (K 1 , K 2 ) serves as a clutch, the first, the second, the third, the fourth, the fifth, and the sixth shape-fit shifting elements (A to F), the first and the second frictional shifting elements (K 1 , K 2 ) and the first, the second, and the third planetary gear sets (P 1 , P 2 and P 3 ) are located within the housing, the first and the second frictional shifting elements (K 1 , K 2 ) are located within the housing between at least the second, the third, the fourth, and the sixth shape-fit shifting elements (B, C, D, F) and the first, the second and the third planetary gear sets (P 1 to P 3 ), the first and the second frictional shifting elements (K 1 , K 2 ) are directly connected by first half-clutches of the frictional shifting elements (K 1 , K 2 ), with two different shafts (ST 1 , S 1 ) of at least the first planetary gear set (P 1 ) and second clutch-halves of the first and the second frictional shifting elements (K 1 , K 2 ) are connectable with at least the second, the third, the fourth, the fifth, and the sixth shape-fit shifting elements (B to F), the first, the second, the third, the fourth, the fifth, and the sixth shape-fit shifting elements (A to F), the first and the second frictional shifting elements (K 1 , K 2 ) and the first and the third planetary gear sets (P 1 and P 3 ) communicate such that at least one of the second, the third, the fourth, the fifth, and the sixth shape-fit shifting elements (B to F) is first engaged with a disengaged one of the first and the second frictional shifting elements (K 1 , K 2 ) prior to engagement of the disengaged frictional shifting element (K 1 , K 2 ) so upon simultaneous disengagement of an engaged frictional shifting element (K 1 or K 2 ) and engagement of the disengaged frictional shifting element (K 2 or K 2 ) continuous traction is achieved for each change in ratio stages.