| 摘要 |
PROBLEM TO BE SOLVED: To prevent a shift shock by delaying the time of supply of hydraulic pressure to a frictional engagement element which is engaged on the high speed stage side, corresponding to the time of discharge of the pressure from the frictional engagement element which is engaged on a low speed side, when the oil temperature is low and moreover when a speed change from a low speed stage to a high speed stage is carried out in the first place after the start of an engine. SOLUTION: When a speed change from a first speed stage to a second speed stage is to be achieved, the duty of first and second brake solenoid valves 35, 32 is put under the command of a controller 37, and by supplying the line pressure adjusted to a prescribed pressure to first and second brake servos 34, 31, the operation of first and second brakes 11, 12 can be controlled. However, since the discharge of the hydraulic pressure become extremely slow because of lowering of viscosity of the oil at the time immediately after the start of an engine, with the temperature lower than a prescribed one (for example, below -10 deg.C), the first brake 11 is controlled so as to start its engagement after correcting the time by which the second brake 12 starts slipping. With this contrivance, a speed change by which the driver's speed- change-feeling never be lacerated can be ensured. |
