Valve arrangement for a fuel system

Patent metadata

Field	Value
Publication number	US-11255269-B2
Application number	US-202016740708-A
Country	US
Kind code	B2
Filing date	Jan 13, 2020
Priority date	Feb 5, 2019
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

The disclosure relates to a valve for a fuel system having a body with at least one inlet and one outlet, the inlet fluidly connected to a pressurised fuel source in use. A shuttle is mounted within the body, the shuttle having a cavity of fixed volume and movable between a first position where fluid is permitted to flow through the inlet and is prevented from flowing through the outlet and a second position where fluid is prevented from flowing through the inlet and is permitted to flow through the outlet. A piston is configured to engage the fluid within the shuttle cavity to move the shuttle between the first and second position. A biasing mechanism biases the shuttle towards the first position and where the shuttle moves towards the second position when the fluid within the shuttle reaches a critical pressure.

First claim

I claim:

1. A valve for a fuel delivery system, comprising:
a valve body comprising an internal cavity, at least one inlet and one outlet, the inlet fluidly connected to a fuel source in use;
a shuttle mounted within the body, the shuttle comprising a partition spanning the internal cavity and moveable relative to the inlet and outlet between a first position where the shuttle blocks the outlet whilst fluid is permitted to flow through the inlet and a second position whereby the outlet is opened whilst fluid is prevented from flowing through the inlet;
a piston configured to engage the fluid within the internal cavity in order to move the shuttle between the first and second position; and
a biasing mechanism arranged to bias the shuttle towards the first position;
wherein the shuttle is moved towards the second position when the fluid within the cavity reaches a threshold pressure, and
wherein the shuttle comprises the partition and a side wall having an open end so as to define an internal volume within the shuttle, wherein the internal volume defines a predetermined metered volume of fuel and the piston extends into the internal volume of the shuttle to expel the fluid therein when the shuttle is in the second position.

2. The valve according to claim 1 , where the valve body has a longitudinal axis and the shuttle is translatable along said axis.

3. The valve according to claim 2 , wherein the inlet and outlet are axially spaced.

4. The valve according to claim 1 , where the shuttle comprises a side wall shaped to occlude the outlet in the first condition.

5. The valve according to claim 4 , wherein the side wall comprises a discontinuity arranged to pass over the outlet as the shuttle moves to the second condition and thereby open the outlet in the second condition.

6. The valve according to claim 4 , wherein the shuttle comprises an outlet, the shuttle outlet aligning with the housing outlet when the shuttle is in the second position.

7. The valve housing according to claim 4 , wherein the shuttle side wall comprises an inlet, the shuttle inlet aligning with the housing inlet when the shuttle is in the first position.

8. The valve according to claim 7 , where the shuttle inlet and the shuttle outlet are axially offset by a distance that is less than a stroke length of the piston and/or an axial spacing between the housing inlet and outlet.

9. The valve according to claim 1 , where the piston is configured to extend into the cavity to expel the fluid therefrom.

10. The valve according to claim 1 , where the piston comprises a solenoid actuator.

11. The valve according to claim 1 , where the housing comprises a second inlet located on an opposing side of the partition from the first inlet and/or separated from the first inlet by the partition.

12. The valve according to claim 1 , wherein the internal cavity is divided into two separate cavity portions by the partition, the two cavity portions being of variable volume according to the location of the shuttle.

13. The valve according to claim 1 , wherein the piston extends fully into the internal volume into abutment with the partition when the shuttle is in the second position.

14. A fuel system for a gas turbine engine, the fuel system comprising the valve of claim 1 .

15. A gas turbine engine comprising the fuel system of claim 14 .

16. The gas turbine engine according to claim 15 , further comprising: an engine core comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan comprising a plurality of fan blades; a gearbox that receives an input from the core shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the core shaft.

17. The gas turbine engine according to claim 16 , wherein: the turbine is a first turbine, the compressor is a first compressor, and the core shaft is a first core shaft; the engine core further comprises a second turbine, a second compressor, and a second core shaft connecting the second turbine to the second compressor; and the second turbine, second compressor, and second core shaft are arranged to rotate at a higher rotational speed than the first core shaft.

18. A valve for a fuel delivery system, comprising:
a valve body comprising an internal cavity, at least one inlet and one outlet, the inlet fluidly connected to a fuel source in use;
a shuttle mounted within the body, the shuttle comprising a partition spanning the internal cavity and moveable relative to the inlet and outlet between a first position where the shuttle blocks the outlet whilst fluid is permitted to flow through the inlet and a second position whereby the outlet is opened whilst fluid is prevented from flowing through the inlet;
a piston configured to engage the fluid within the internal cavity in order to move the shuttle between the first and second position; and
a biasing mechanism arranged to bias the shuttle towards the first position;
wherein the shuttle is moved towards the second position when the fluid within the cavity reaches a threshold pressure, and
wherein the valve housing and shuttle comprise a first valve housing and a first shuttle, the valve comprising a further valve housing and a further shuttle sharing a common piston with the first valve housing and the first shuttle, and configured such that when the first shuttle is in the first position, the further shuttle is in the second position.

19. The valve according to claim 18 , wherein opposing ends of the piston engage within the first and further valve housings respectively.

Assignees

• Rolls Royce Plc

Inventors

• Smith Michael R

Classifications

• F02C9/266

  specially adapted for gas turbines with intermittent fuel injection · CPC title

• F16K3/26

  with fluid passages in the valve member · CPC title

• F16K21/16

  closing after a predetermined quantity of fluid has been delivered (F16K21/10 takes precedence) · CPC title

• F16K11/0655

  with flat slides · CPC title

• F02C7/232 Primary

  Fuel valves {(control of fuel supply by means of fuel metering valves F02C9/263)}; Draining valves or systems (valves in general F16K) · CPC title