Patent attributes
An automatic transmission has a first clutch shaft that constantly connects first and fourth planetary gear sets, a second clutch shaft that constantly connects second and third planetary gear sets, and a third clutch shaft that constantly connects the third and first planetary gear sets. A drive shaft is constantly connected to the fourth planetary gear set; an output shaft is constantly connected to the third planetary gear set. The first planetary gear set is directly connected to two shift elements, the second planetary gear set is directly connected to four shift elements, the third planetary gear set is directly connected to two shift elements, the fourth planetary gear set is directly connected to four shift elements. The drive shaft is directly connected to only one shift element. The output shaft is directly connected to only one shift element. A seventh shift element is directly connected to the drive shaft and the second and fourth planetary gear sets.