| 摘要 |
PURPOSE: A gear train of an automatic transmission for a vehicle is provided to improve dynamic power transfer performance by increasing the number of transmission steps. CONSTITUTION: A gear train of an automatic transmission for a vehicle comprises a first planetary gear set(PG1) and a second planetary gear set(PG2). The first planetary gear set(PG1) has first, second, third and fourth rotation elements(N1,N2,N3,N4). The first rotation element comprises a second linear gear(S2) and operates with a fixed element always. The second rotation element comprises a first planetary carrier(PC1) and a second ring gear(R2). The third rotation element comprises a first ring gear(R1). The fourth rotation element comprises a first linear gear(S1) and a second planetary carrier(PC2). The second planetary gear set has fifth, sixth, seventh and eighth rotation element(N5,N6,N7,N8). The fifth rotation element comprises a third linear gear(S3). The sixth rotation element comprises a third planetary carrier(PC3). The seventh rotation element comprises a third ring gear(R3). The eighth rotation element comprises a fourth linear gear(S4). The gear train of the automatic transmission for a vehicle further includes a friction member. The friction member comprises clutches(C1,C2,C3,C4,C5) and brakes(B1,B2). |
