Pneumatic hydraulic position control circuit

When high positioning accuracy is required, pneumatic hydraulic position control circuit can be used.

Figure 1 shows the position control circuit with parallel air-liquid damping cylinder. In the process of extending and returning the damping cylinder, two two position two-way hydraulic solenoid valves can stop the damping cylinder. Once the movement stops, the three position valve is in the middle position. The pressure of two chambers of the cylinder is atmospheric pressure, which makes the operation more convenient.

Fig. 2 shows the circuit in which the gas-liquid converter is used to control the stop position in the piston rod, and the one-way throttle valve is used to control the return speed of the cylinder. When the two position two-way solenoid valve cuts off the return oil circuit, it can quickly stop the piston rod at any position of the stroke.