Planetary gear train of automatic transmission for vehicle

摘要

A planetary gear train of an automatic transmission for a vehicle is disclosed. The planetary gear train can achieve ten forward speeds and one reverse speed by combining four planetary gear sets with three clutches and three brakes. Therefore, the planetary gear train can improve power delivery efficiency and fuel economy by achieving multiple shift-speeds of the automatic transmission.

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 a changed torque; a first planetary gear set having three rotation elements and disposed on the input shaft; a second planetary gear set having three rotation elements and disposed at a rear of the first planetary gear set on the input shaft; a third planetary gear set having three rotation elements and disposed at a rear of the second planetary gear set on the input shaft; a fourth planetary gear set having three rotation elements and disposed at a rear of the third planetary gear set on the input shaft; a first rotation shaft provided with a first rotation element of the first planetary gear set and a first rotation element of the second planetary gear set directly connected to the first rotation element of the first planetary gear set, and selectively connected to a transmission housing; a second rotation shaft provided with a second rotation element of the first planetary gear set; a third rotation shaft provided with a third rotation element of the first planetary gear set and directly connected to the input shaft; a fourth rotation shaft provided with a second rotation element of the second planetary gear set and selectively connected to the second rotation shaft or the transmission housing; a fifth rotation shaft provided with a third rotation element of the second planetary gear set, a first rotation element of the third planetary gear set and a first rotation element of the fourth planetary gear set; a sixth rotation shaft provided with a second rotation element of the fourth planetary gear set and selectively connected to the input shaft or the second rotation shaft; a seventh rotation shaft provided with a second rotation element of the third planetary gear set and a third rotation element of the fourth planetary gear set, and connected to the output shaft; an eighth rotation shaft provided with a third rotation element of the third planetary gear set and selectively connected to the transmission housing; and six frictional elements interposed between the rotation shafts or between the rotation shaft and the input shaft or the transmission housing.