An electrohydraulic pressure regulating valve comprises a variable orifice disposed between a supply port and a control port and has a fixed size vent orifice disposed downstream of the variable orifice and in parallel with the control port to reduce the flow forces acting on the spool so that the valve is less sensitive to solenoid and spool quality and has improved pressure control capability.Balance Valves Load sensing variable displacement pumps are sometimes utilized for continuously driving a rotary motor wherein the displacement of the pump is controllably regulated to change the speed of the motor. The electrohydraulic pressure regulating valves commonly used for controlling the displacement of the pump typically have a fixed size orifice disposed upstream of a variable orifice.API Cast Steel Valves The upstream variable orifice can be defined by either a spool or a poppet type metering element with the displacement thereof being controlled by a solenoid. One of the problems encountered with the pressure regulating valves having a spool is the repeatability of the area control of the valve opening due to the quality of the solenoid and/or spool and to high flow forces acting on the spool caused by high pressure drops across the spool.REDUCING VALVES A severe stability problem was encountered with the poppet type pressure regulating valves in this environment. In view of the above, it is readily apparent that the structure of the present invention provides an improved electrohydraulic pressure regulating valve that reduces the flow forces acting on the spool so that the valve is less sensitive to solenoid and spool quality and has improved pressure control capability. This is accomplished by positioning a variable orifice between a supply port a fixed size vent orifice disposed downstream of the variable orifice in parallel with the control port.

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