| 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 first and second planetary gear set(PG1,PG2). The first planetary gear set has a first linear gear(S1), a first ring gear(R1) and a first planetary carrier(PC1). The first linear gear operates with a fixed element always. The second planetary gear set is connected to the first planetary gear set. The second planetary gear set has a second linear gear(S2), a second ring gear(R2), a second planetary carrier(PC2) and a first friction member. The first friction member connects two of the second linear gear, and the second ring gear and the second planetary carrier variably. The gear train of the automatic transmission for a vehicle further includes a third planetary gear set(PG3) and a friction member. The third planetary gear set is combined to the first and the second planetary gear sets. The third planetary gear set has a third linear gear(S3), a fourth linear gear(S4), a third planetary carrier(PC3) and a third ring gear(R3). The third linear gear and the third planetary gear operate with a selectively fixed element. The second friction member is combined with the first, the second and the third planetary gear sets. The second friction member has clutches(C1,C2,C3,C4,C5) and brakes(B1,B2). |
