| 摘要 |
PURPOSE:To set an automatic transmission at the optimum operating condition by incorporating an electric control device into the hydraulic control device of a vehicle automatic transmission and compensating a part of the function of said hydraulic control device in the high speed range of a vehicle by said electric control device. CONSTITUTION:A vehicle speed sensor 102 which generates electric signals in accordance with the speed of a vehicle and a throttle sensor 103 which generates electric signals in accordance with suction throttle opening are provided. And, the outputs from the sensors 102, 103 are inputted into an electric airthmetic operation unit 101 while a solenoid valve 91 is provided in an oil passage 43k which is connected to the pilot chamber 90 of an overdrive control valve 58 through a shuttle valve 89 and this solenoid valve 91 is controlled by means of the electric arithmetic operation unit 101. Thereby, a part of the function of a hydraulic control device in the high speed range of a vehicle can be compensated by an electric control device, eliminating the operational error of the hydraulic control device. Accordingly, an automatic transmission can be set at the optimum operating condition. |
