Proportional flow control of a fluid pump assembly

摘要

A pump control assembly having a flow control assembly disposed between the first end of a load sensing valve and a fluid pump is disclosed. The flow control assembly may include an orifice, a first valve assembly, and a second valve assembly. When the first valve assembly is in an open position and the second valve assembly is in a first position, fluid passing through the orifice is directed to a fluid reservoir and to the load sensing valve. When the first valve assembly is in a closed position and the second valve assembly is in a second position, all fluid passing through the orifice is directed to the load sensing valve. An electronic controller can be configured to transmit an output current to the first and second valve assemblies in response to an operational parameter of a prime mover supplying power to the fluid pump.

主权项

1. A pump control assembly comprising:
(a) a fluid pump assembly including:
i. a fluid pump having a fluid outlet and a fluid inlet in communication with a fluid reservoir, the fluid pump including a variable displacement mechanism;ii. a load sensing valve adapted to adjust the position of the variable displacement mechanism, the load sensing valve having a first end and an oppositely disposed second end; (b) an actuator in fluid communication with the fluid pump assembly; (c) a flow control assembly disposed between the first end of the load sensing valve and the fluid pump including:
i. an orifice, a first valve assembly, and a second valve assembly;ii. wherein when the first valve assembly is in an open position and the second valve assembly is in a first position, a portion of the fluid passing through the orifice is directed to the fluid reservoir and another portion of the fluid passing through the orifice is directed to the first end of the load sensing valve;iii. wherein when the first valve assembly is in a closed position and the second valve assembly is in a second position, all fluid passing through the orifice is directed to the first end of the load sensing valve; and (d) an electronic control unit in electrical communication with the first and second valve assemblies, wherein the electronic control unit transmits an output current to the first and second valve assemblies in response to an operational parameter of a prime mover that supplies power to the fluid pump.