| 摘要 |
PURPOSE:To suppress a speed change shock by obtaining, at the time of the speed change an estimated value of speed change mechanism input side rotation al speed, from gear ratio and a car speed before a speed change, and obtaining an engine speed blowup amount based on a difference from the actual value and correcting an operating pressure so as to reduce this blowup amount. CONSTITUTION:In a control unit 100, a duty solenoid valve 33 is controlled by a control means 105, and a line pressure (operating pressure) of a hydraulic control circuit 30 is controlled and supplied to friction elements of a multistep speed change mechanism 10 to perform a speed change. At the time of this speed change, an estimated value of a turbine rotational speed is obtained by an arithmetic means 106 from gear ratio and a car speed from a sensor 103, before the speed change, and an engine speed blowup amount at the time of speed change is obtained being based on a difference from the turbine rota tional speed detected by a sensor 101. A control amount of the line pressure is corrected in a direction of reducing the engine speed blowup amount by a speed change time operating pressure control means 107. Thus by properly controlling the operating pressure at the time of the speed change, a speed change shock can be effectively suppressed. |
