PLANETARY GEAR TRAIN OF AUTOMATIC TRANSMISSION FOR VEHICLES

摘要

Eight or more forward speeds and at least one reverse speed is achieved by a planetary gear train of an automatic transmission for a vehicle including an input shaft, an output shaft, three planetary gear sets respectively having three rotation elements, and six control elements for selectively interconnecting the rotation elements.

主权项

1. A planetary gear train of an automatic transmission for a vehicle, comprising:
an input shaft receiving torque of an engine; an output shaft outputting changed torque; a first planetary gear set having first, second, and third rotation elements; a second planetary gear set having fourth, fifth, and sixth rotation elements; a third planetary gear set having seventh, eighth, and ninth rotation elements; a first rotation shaft including the first rotation element and the ninth rotation element and selectively connectable to the input shaft; a second rotation shaft including the second rotation element and the fifth rotation element; a third rotation shaft including the third rotation element and selectively connectable to the input shaft or a transmission housing; a fourth rotation shaft including the fourth rotation element and selectively connectable to the first rotation element; a fifth rotation shaft including the sixth rotation element and directly connected to the transmission housing; a sixth rotation shaft including the seventh rotation element and selectively connectable to the second rotation element; and a seventh rotation shaft including the eighth rotation element and directly connected to the output shaft so as to selectively connectable to the fourth rotation shaft.