Pilot operated throttling valve for constant flow pump

摘要

A pilot operate, throttling valve is provided for a pump that has inlet valving sufficient to permit the pump to operate with charged fluid at a varying inlet pressure. The throttling valve includes a flow control slave valve operated by a pressure unbalanced mechanical actuator. The pressure differential in the actuator controlling the flow in the slave valve results from a constant pressure produced by a conventional pressure regulating valve generating an actuator force which is reduced by a controlled pressure generated from a solenoid actuated control valve. Because pressure, not flow, controls the pilot, the throttling valve is particularly suited for HEUI applications where the ECM must quickly and accurately control the pump irrespective of viscosity and flow considerations of the pumped oil.