Valve assembly with oil shut-off valve

Patent metadata

Field	Value
Publication number	US-10001060-B2
Application number	US-201514743258-A
Country	US
Kind code	B2
Filing date	Jun 18, 2015
Priority date	Jun 18, 2015
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

A gas turbine engine valve assembly having an oil shut-off valve and a compensating valve fluidly connected thereto. The compensating valve, in a first position, restricts access to a pressure-reducing oil flow path leading to an oil reservoir, and in a second position, provides access to the pressure-reducing oil flow path. The pressure-reducing oil flow path is defined by fluid flow between housing apertures, a laminar hole and an orifice. The valve assembly is operable between a first configuration, wherein the oil shut-off valve is in a fluid transfer position and a piston of the compensating valve is in a closed position to direct oil toward the engine component, and a second configuration, wherein the oil shut-off valve is in the shut-off position and the piston is in a open position to direct oil toward the oil reservoir via the pressure-reducing oil flow path.

First claim

The invention claimed is:

1. A valve assembly of an oil system for a gas turbine engine, comprising:
an oil shut-off valve operating between a fluid transfer position to direct oil toward an engine component to be lubricated, and a shut-off position to block the flow of oil toward the engine component; and
a compensating valve fluidly connected to the oil shut-off valve and comprising:
a housing defining a central axis, the housing having a plurality of spaced apart housing apertures disposed about a periphery of the housing;
a piston disposed within the housing and displaceable relative to the housing between an open position and a closed position, the piston exposing the housing apertures in the open position to direct oil through the housing apertures along a pressure-reducing oil flow path leading to an oil reservoir, and the piston blocking the housing apertures in the closed position to restrict access to the pressure-reducing oil flow path, the pressure-reducing oil flow path defined by oil flow through the housing apertures toward the oil reservoir;
a biasing element disposed within the housing at one end thereof, the biasing element engaging the piston to act thereon, the biasing element biasing the piston in one of the open and closed positions thereof; and
a laminar hole and an orifice, the laminar hole extending through one of the piston and the housing, and the orifice extending through the other one of the piston and housing, the laminar hole and orifice creating a pressure gradient across the piston to displace the piston, the laminar hole extending through the housing at the same end thereof as the biasing element, the laminar hole and the orifice being in serial flow communication;

the valve assembly operable between a first configuration and a second configuration, the oil shut-off valve being in the fluid transfer position and the piston being in the closed position to direct oil toward the engine component in the first configuration, the oil shut-off valve being in the shut-off position and the piston being in the open position to direct oil toward the oil reservoir via the pressure-reducing oil flow path in the second configuration.

2. The valve assembly of claim 1 , wherein the piston has a piston body and a piston head extending from the piston body, at least one of the orifice and the laminar hole extending through the piston head to allow oil to flow therethrough.

3. The valve assembly of claim 2 , wherein the piston body has a plurality of piston apertures disposed circumferentially about a periphery of the piston body, the piston apertures aligned with the housing apertures upon the piston being in the open position to direct oil along the pressure-reducing flow path through the piston and housing apertures and toward the oil reservoir.

4. The valve assembly of claim 2 , wherein the piston body blocks the housing apertures upon the piston being in the closed position, and wherein the piston body exposes the housing apertures upon the piston being in the open position to direct oil through the housing apertures along the pressure-reducing flow path and toward the oil reservoir.

5. The valve assembly of claim 1 , wherein the orifice extends through the housing at the same end thereof as the biasing element, the laminar hole and the orifice being in serial flow communication and coaxial with the central axis of the housing.

6. The valve assembly of claim 1 , further comprising an assembly housing defining an inner chamber and having an oil inlet and an oil outlet, both the oil shut-off valve and the compensating valve disposed within the inner chamber of the assembly housing, the oil inlet supplying oil simultaneously to both the oil shut-off valve and to the compensating valve.

7. The valve assembly of claim 1 , wherein the oil shut-off valve and the compensating valve are in fluid communication via an oil connection line.

8. The valve of claim 1 , wherein each said housing aperture includes an elongated cross portion transverse to the central axis.

9. The valve of claim 1 , wherein the compensating valve has a thermal compensator, the thermal compensator displacing the piston as a function of a temperature of the oil.

10. An oil system of a gas turbine engine having bearing cavities lubricated by the oil system, the oil system comprising:
an oil reservoir;
one or more scavenge pumps in fluid communication with the bearing cavities of the gas turbine engine and the oil reservoir, the scavenge pumps collecting and directing used oil from the bearing cavities into the oil reservoir;
a supply pump providing oil flow from the oil reservoir toward one or more components of the gas turbine engine, including the bearing cavities;
a valve assembly downstream of the supply pump and upstream of the bearing cavities, the valve assembly operable between a first configuration to direct oil toward the bearing cavities and a second configuration to block the flow of oil toward the bearing cavities, the valve assembly including:
an oil shut-off valve operating between a fluid transfer position and a shut-off position; and
a compensating valve fluidly connected to the oil shut-off valve and comprising a housing having a plurality of spaced apart housing apertures disposed about a periphery of the housing, a piston disposed within the housing and displaceable relative to the housing between an open position and a closed position, the piston exposing the housing apertures in the open position to direct oil through the housing apertures along a pressure-reducing oil flow path leading to the oil reservoir, and the piston blocking the housing apertures in the closed position to restrict access to the pressure-reducing oil flow path, the pressure-reducing oil flow path defined by oil flow through the housing apertures toward the oil reservoir;
wherein in the first configuration of the valve assembly the oil shut-off valve is in the fluid transfer position and the piston of the compensating valve is in the closed position, and in the second configuration of the valve assembly the oil shut-off valve is in the shut-off position and the piston of the compensating valve is in the open position.

11. The oil system of claim 10 , wherein the valve assembly includes an assembly housing defining an inner chamber and having an oil inlet and an oil outlet, both the oil shut-off valve and the compensating valve disposed within the inner chamber of the assembly housing, the oil inlet supplying oil simultaneously to both the oil shut-off valve and to the compensating valve.

12. The oil system of claim 10 , wherein the compensating valve includes a laminar hole and an orifice, the laminar hole extending through one of the piston and the housing, and the orifice extending through the other one of the piston and housing, the laminar hole and orifice creating a pressure gradient across the piston to displace the piston.

13. The oil system of claim 12 , wherein the piston of the compensating valve has a piston body and a piston head extending from the piston body, at least one of the orifice and the laminar hole extending through the piston head to allow oil to flow therethrough.

14. The valve assembly of claim 13 , wherein the piston body has a plurality of piston apertures disposed circumferentially about a periphery of the piston body, the piston apertures aligned with the housing apertures upon the piston being in the open position to direct oil through the piston body and housing apertures and toward the oil reservoir via the pressure-reducing oil flow path.

15. The valve assembly of claim 13 , wherein the piston body blocks the

Assignees

• Pratt & Whitney Canada

Inventors

• Faubert Charles
• Vinski Johnny
• Soukhostavets Valeri

Classifications

• F02C7/06 Primary

  Arrangements of bearings (bearings F16C); Lubricating ({of turbo machines F01D25/18; of machines or} engines in general F01M) · CPC title

• F16K17/02

  opening on surplus pressure on one side; closing on insufficient pressure on one side (check valves F16K15/00) · CPC title

• F16K3/32

  Means for additional adjustment of the rate of flow · CPC title

• F16K3/029

  with two or more gates · CPC title

• F16K31/12

  actuated by fluid ({fluid-actuated lift valves F16K1/126} ; fluid-actuated check valves F16K15/00; fluid-actuated safety valves F16K17/00) · CPC title