Patent ID: 9657815
Date: 2017-05-23
CPC Classifications: F16H

Claim:
1. A planetary gear train for an automatic transmission of a vehicle, comprising: an input shaft receiving torque of an engine; an output shaft outputting changed torque; a first planetary gear set including a first rotation element, a second rotation element, and a third rotation element; a second planetary gear set including a fourth rotation element, a fifth rotation element, and a sixth rotation element; a third planetary gear set including a seventh rotation element, an eighth rotation element, and a ninth rotation element; a fourth planetary gear set including a tenth rotation element, an eleventh rotation element, and a twelfth rotation element; and seven friction elements disposed to selectively connect the rotation elements with the rotation element and selectively connect the rotation elements with a transmission housing, and wherein the input shaft is continuously connected to the second rotation element, the output shaft is continuously connected to the eleventh rotation element, the first rotation element is continuously connected to the sixth rotation element, the first rotation element is continuously connected to the eighth rotation element, the first rotation element is continuously connected to the tenth rotation element, the fifth rotation element is continuously connected to the ninth rotation element, the output shaft is selectively connected to the third rotation element, and wherein three friction elements among the seven friction elements are operated for achieving ten forward speed stages and at least one reverse speed stage.