US 6,439,199 B2 · Pilot operated throttling valve for constant flow pump

Abstract

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.

Claims29

Dependent claims

In an internal combustion engine having a hydraulically-actuated electronically-controlled fuel injection system of the type including a fuel injector valving high pressure fluid in response to commands from an ECM to timely inject a metered quantity of fuel into the engine's combustion chamber;

the injector in fluid communication with the outlet of a high pressure pump in turn having an inlet in fluid communication with a low pressure pump;
the improvement comprising:
said high pressure pump being of a type in which the flow of high pressure fluid from the outlet thereof can be varied in response to a variation of flow at the inlet of said high pressure pump, and
a throttling valve having an inlet in fluid communication with said low pressure pump and an outlet in fluid communication with said high pressure pump, said throttling valve having a flow control slave valve providing a variably set flow from said throttling valve inlet to said throttling valve outlet and a pilot operated, mechanical actuator controlling said variably set flow of said slave valve.

1 more element

The combination comprising:

a pump having an inlet receiving incoming fluid at an inlet pressure and an outlet for transmitting outgoing fluid at a higher pressure, and
a pilot operated throttling valve regulating the flow of said incoming fluid to said pump inlet whereby the flow of said outgoing fluid may be regulated, wherein said pump has a piston bore and an orifice providing timed communication of said fluid from said inlet through said orifice to said piston bore.

Dependencies are inferred from the claim text.

Pilot operated throttling valve for constant flow pump

Life of this patent

Pilot operated throttling valve for constant flow pump

Life of this patent

Abstract

Claims29