Study on Autoshift Control of Vehicular Planetary Transmission Controlled by Motor-Driven Rotational Valve

An autoshift control method of vehicular planetary transmission controlled by hydraulic rotational valve is realized.Through analyzing the working characteristics of hydraulic rotational valve,a direct current electromotor is used as the driver of the rotational valve.An autoshift control system is added to the original hydraulic control system,and a proper control strategy of autoshift is made up.Tests showed that the motor-driven rotational valve satisfies the demand of autoshift control,simplifies the operation of shifting,and improves the overall performance of the vehicle.