Two valve actuators with different values for switching-on time and switching-off time. Valve Actuator 1 is set to start from the retracted position, while Valve Actuator 2 from the extended position. Both actuators are driven with the same pulse signal.

A use of a double-acting valve actuator. All three actuators are driven by the same pulse signals. A pulse is first applied to port A and after 1.5 s delay a pulse is applied to port B. Actuator A is set to start from the "Extended positive" position, while actuator C starts from the "Extended negative" position. As a result, actuators A and C move to the neutral position at the start of simulation and reach this position before the first pulse is applied. The actuators strokes, switch-on, and switch-off times are set to different values to illustrate the effects of these parameters.

A model of a two-stage servo-valve with a 4-way, 3-position spool valve in the power stage and a flapper-nozzle amplifier in the pilot stage. The flapper is connected to the armature of a torque motor, which in the example is represented with an ideal translational force source. The servo-valve shown in the example is equipped with the spring feedback between the flapper and the spool of the main valve. To investigate the behavior of such a valve, axial hydraulic forces on all four spool orifices are accounted for in the model by using Spool Orifice Hydraulic Force blocks. The servo-valve controls a simple double-acting cylinder in an open-loop application.