| 摘要 |
PURPOSE:To reduce transmission shockings at the start up by setting the hydraulic pressure at a low level to be supplied to a friction engaging element for achieving a high speed transmission step which is engaged to prevent creep. CONSTITUTION:As soon as an acceleration pedal switch 146 and a rotation sensor 144 detect stoppage of a vehicle, an electronic controller 112 engages a front clutch 24 with a rear clutch 26 to achieve the third speed transmission step. While the third speed is achieved during the stoppage of the vehicle, the electronic controller 112 actuates a solenoid valve 106 continuously to retain the hydraulic pressure supplied to a front clutch 24 from a hydraulic control valve 96 through a 1-2 speed shift valve 100, a 2-3 speed and 4-3 speed valves 102 at a lower level than the hydraulic pressure supplied to a rear clutch 26. This can secure the time to complete the switching to the torque transmission sufficiently at the start up thereby recducing transmission shockings. |
