| 摘要 |
PURPOSE:To keep off any shift shock attending on a down-shift, in an automatic transmission which is provided with a common one-way clutch in both high and low speed power transmission routes, and this one-way clutch is made possible to transmit power only to the output side from the input side. CONSTITUTION:An automatic transmission AT has a one-way clutch 203 in the multistage shift mechanism 2. In this shift mechanism 2, a forward clutch 202 is clamped at a D range 1-speed and an input from a converter output shaft 7 is transmitted to an output shaft 215 by way of the one-way clutch 203. On the other hand, at the D-range 2-speed, the forward clutch 202 and a 2-4 brake 214 are clamped to each other, and the input out of the torque converter 7 is transmitted to the output shaft 215 by way of the one-way clutch 203. A down-shift to the 1-speed from the 2-speed in this D range is fundamentally based on a control map, but when the one-way clutch 202 is not in a slipping state, this down-shift is prohibited, and until this clutch 202 has come to the slipping state, the down-shift is not executed. |
