Transfer valve system
AssigneeSikorsky Aircraft Corporation
InventorsBoris K. Kogan, William F. Lange
Life of this patent
Estimating the term…
Abstract
A hydraulic transfer valve system has a main valve selectively placing one of a primary and secondary hydraulic system in communication with a hydraulic load. A pilot valve provides a toggling action between the primary and secondary systems with respect to pressure changes in such systems.
Claims14
A hydraulic transfer valve system for coupling one of primary and secondary hydraulic systems, each having a source and a return, to a hydraulic load having an input and a return, the hydraulic transfer valve system comprising:
- a first valve;
- a second valve;
- and
- a passageway coupling the first valve to the second valve and having first and second ports at said first and second valves, respectively,
- the first valve having:
- a first condition in which the first valve:
- provides communication between the primary hydraulic system source and the hydraulic load input;
- provides communication between the primary hydraulic system return and the hydraulic load return;
- blocks communication between the secondary hydraulic system source and the hydraulic load input;
- provides communication between the secondary hydraulic system return and the hydraulic load return;
- and
- blocks the passageway first port;
- and a second condition in which the first valve:
- provides communication between the secondary hydraulic system source and the hydraulic load input;
- provides communication between the secondary hydraulic system return and the hydraulic load return;
- blocks communication between the primary hydraulic system source and the hydraulic load input;
- provides communication between the primary hydraulic system return and the hydraulic load return;
- and
- does not block the passageway first port;
- and the second valve having;
- a first condition in which the second valve blocks the passageway second port;
- and
- a second condition in which the second valve does not block the passageway second port and wherein with the first valve in its second condition, the passageway permits a flow from the primary hydraulic system source to the primary hydraulic system return.
A hydraulic transfer valve system for coupling one of primary and secondary hydraulic systems, each having a source and a return, to a hydraulic load having an input and a return, the hydraulic transfer valve system comprising:
- a first valve;
- a second valve;
- and
- a passageway coupling the first valve to the second valve and having first and second ports at said first and second valves, respectively,
- the first valve having:
- a first condition in which the first valve:
- provides communication between the primary hydraulic system source and the hydraulic load input;
- provides communication between the primary hydraulic system return and the hydraulic load return;
- blocks communication between the secondary hydraulic system source and the hydraulic load input;
- and
- provides communication between the secondary hydraulic system return and the hydraulic load return;
- and
- a second condition in which the first valve:
- provides communication between the secondary hydraulic system source and the hydraulic load input;
- provides communication between the secondary hydraulic system return and the hydraulic load return;
- blocks communication between the primary hydraulic system source and the hydraulic load input;
- and
- provides communication between the primary hydraulic system return and the hydraulic load return;
- and
- at least one of the first and second valves having means for piloting the first valve so that:
- with the primary and secondary hydraulic systems initially operating normally and the first valve in the first condition, a decrease in a pressure of the primary hydraulic system source relative to the secondary hydraulic system source causes the first valve to toggle to the second condition;
- and
- with the secondary hydraulic system initially operating normally and the primary hydraulic system source initially operating with an insufficient pressure and the first valve in the second condition, a sufficient increase in the pressure of the primary hydraulic system source relative to the secondary hydraulic system source causes the first valve to toggle to the first condition.
Dependencies are inferred from the claim text.