| 摘要 |
PURPOSE: A power transmission device for an automatic transmission reduces the whole length of the automatic transmission while increasing the number of planetary gear sets. CONSTITUTION: A second planetary gear set (50) receives power from a first planetary gear set. A third planetary gear set is installed at a first transmission shaft and receives the power from the first planetary gear set or the second planetary gear set. A fourth planetary gear set (80) is installed at a second transmission shaft and receives the power from the third planetary gear set. A gear unit (100) transmits the power between the third planetary gear set and the fourth planetary gear set. A friction element fastens or releases the first planetary gear set and transmits or blocks the power between the first planetary gear set, the second planetary gear set, the third planetary gear set, and the fourth planetary gear set. |
