Hydraulic Circuit with Single-Acting Cylinder

This example shows the use of a single-acting cylinder. The cylinder is controlled by an electrically-operated 3-way directional valve, and drives a load consisting of a mass, viscous friction, and preloaded spring. The pump unit is assumed to be powerful enough to maintain constant pressure at the valve inlet.

The valve is simulated by a 2-Position Valve Actuator block and a 3-Way Directional Valve block. At initial position, path A-T is opened, thus connecting the cylinder to the tank. When the signal generated by the Sine Wave generator crosses 12, the valve starts moving, causing path P-A to open and path A-T to close. As a result, the cylinder becomes connected to the pressure source and starts moving the load.