Back to results
US 11,067,101 B2Granted
Hydraulic control valve configured to use a pilot signal as a substitute load-sense signal
AssigneeParker-Hannifin Corporation
InventorsBrian Slattery, Micheal E. Harman
Life of this patent
Estimating the term…
Abstract
An example valve assembly is configured: generate a valve load-sense pressure signal indicative of a pressure level at a workport of an actuator; generate a pilot fluid signal to be communicated to a worksection of a valve assembly to enable shifting a spool in the worksection; compare a first pressure level of the valve load-sense pressure signal to a second pressure level of the pilot fluid signal; and communicate the pilot fluid signal to a load-sense port fluidly coupled to a load-sensing source of pressurized fluid when the second pressure level of the pilot fluid signal exceeds the first pressure level of the valve load-sense pressure signal.
Claims20
A valve assembly comprising:
- an inlet section configured to receive pressurized fluid from a load-sensing pump;
- at least one worksection configured to control fluid flow to and from an actuator, wherein the at least one worksection includes a body defining a bore and a spool axially movable in the bore;
- a load-sense passage traversing the at least one worksection and configured to communicate a load-sense pressure signal having a first pressure level representing a load-induced pressure at the actuator;
- a plurality of pilot fluid passages configured to communicate a pilot fluid signal having a second pressure level to the at least one worksection so as to move the spool in the bore;
- a valve load-sense port configured to be fluidly coupled to the load-sensing pump to provide either the load-sense pressure signal or the pilot fluid signal as a pressure signal to the load-sensing pump, wherein the load-sensing pump is configured to provide pressurized fluid having a pressure level higher than a respective pressure level of the pressure signal;
- a valve configured to:
- (i) receive the pilot fluid signal, and (ii) in response to the second pressure level of the pilot fluid signal being higher than the first pressure level of the load-sense pressure signal, provide the pilot fluid signal to the valve load-sense port as the pressure signal to be provided to the load-sensing pump.
4 more elements
A hydraulic system comprising:
- a load-sensing pump having a pump load-sense port configured to receive a pressure signal, wherein the load-sensing pump is configured to generate pressurized fluid having a pressure level based on the pressure signal;
- an actuator;
- and
- a valve assembly configured to control fluid flow from the load-sensing pump to the actuator, the valve assembly comprising:
- an inlet section configured to receive pressurized fluid from the load-sensing pump,
- a valve load-sense port configured to be fluidly coupled to the pump load-sense port to provide the pressure signal to the load-sensing pump,
- at least one worksection comprising:
- (i) a body defining a bore, and (ii) a spool axially movable in the bore to control fluid flow to and from the actuator,
- a load-sense passage traversing the at least one worksection and configured to communicate a load-sense pressure signal having a first pressure level and representing a load-induced pressure of the actuator,
- a plurality of pilot fluid passages configured to communicate a pilot fluid signal having a second pressure level to the at least one worksection so as to move the spool in the bore, and
- a valve configured to:
- (i) receive the pilot fluid signal, and (ii) in response to the second pressure level of the pilot fluid signal being higher than the first pressure level of the load-sense pressure signal, provide the pilot fluid signal to the valve load-sense port to be communicated to the pump load-sense port as the pressure signal.
9 more elements
A method comprising:
- generating a valve load-sense pressure signal indicative of a pressure level at a workport of an actuator;
- generating a pilot fluid signal to be communicated to a worksection of a valve assembly, such that when a pilot valve disposed at an end of a spool in the worksection is actuated, the pilot fluid signal is communicated to the end of the spool causing the spool to shift;
- comparing a first pressure level of the valve load-sense pressure signal to a second pressure level of the pilot fluid signal;
- and
- communicating the pilot fluid signal to a valve load-sense port fluidly coupled to a load-sensing pump of pressurized fluid when the second pressure level of the pilot fluid signal exceeds the first pressure level of the valve load-sense pressure signal, such that the load-sensing pump provides pressurized fluid having pressure level higher than the second pressure level.
2 more elements
Dependencies are inferred from the claim text.