Aerospace Electrohydraulic Servo Valve

These valves are a series of three- or four-way electrohydraulic servovalves (EHSVs) commonly used to control position, velocity, and force in a variety of hydraulic system, fuel system, and engine control applications. Driving aerospace hydraulic actuators or motors in closed-loop servosystems, the EHSVs provide flows to 10 GPM at 1000 psi drop across the valve. The first stage is driven by an efficient force motor that is balanced so that lateral accelerations have little effect on output flow.
The electrohydraulic servovalves provide unparalleled performance due to the highly reliable jet-pipe first-stage and large second-stage spool design. The result is an exceptionally contamination-resistant, erosion-tolerant, and high-flow servovalve that's designed to last. With an ability to perform in a contaminated environment, the Parker EHSV allows particles as large as 208 microns (0.008") to pass through the first stage without difficulty.
Because the first-stage fluid impinges on a receiver that is fixed to the second stage, the Jet-Pipe® motor has low first-stage noise. The integrity of the projector jet stream results in optimum hydraulic efficiency (first-stage pressureflow recovery) and better dynamic performance at low fluid temperatures.