FUEL METERING VALVE ASSEMBLY INCLUDING THERMAL COMPENSATION MECHANISM

• US 20090301575A1
• Filed: 10/24/2007
• Published: 12/10/2009
• Est. Priority Date: 10/24/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Arnett, Eric M.
• Granted Patent: US 7,784,487 B2
• Time in Patent Office: Days
• US Class Current: 137/468
• CPC Class Codes: F02C 7/232 Fuel valves control of fuel supply by means of fuel metering valves F02C9/263; Draining valves or systems valves in general F16K
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft
• CPC Class Codes: Y10T 137/7737 Thermal responsive
• CPC Class Codes: Y10T 137/8242 Electrical

Abstract

A metering valve assembly is provided for metering a fluid. The metering valve assembly includes a position sensor, metering valve, and a thermal compensation mechanism. The metering valve includes a valve housing having a flow passage therethrough, and a valve element movably mounted within the valve housing. The thermal compensation mechanism is coupled between the position sensor and the valve element and configured to adjust the displacement of the position sensor relative to the valve element as a function of fluid temperature.

Claims

1. A metering valve assembly for metering a fluid, comprising:

a position sensor;

a metering valve, comprising;

a valve housing having a flow passage therethrough; and

a valve element movably mounted within the valve housing; and

a thermal compensation mechanism coupled between the position sensor and the valve element, the thermal compensation mechanism configured to adjust the displacement of the position sensor relative to the valve element as a function of fluid temperature.

2. A metering valve assembly according to claim 1 wherein the thermal compensation mechanism increases the displacement of the position sensor relative to the valve element as fluid density decreases over an operative temperature range.

3. A metering valve assembly according to claim 1 wherein the position sensor comprises:

a sensor body coupled to the valve housing; and

a sensor input movably coupled to the sensor body and fixedly coupled to the thermal compensation mechanism.

4. A metering valve assembly according to claim 3 wherein the position sensor is a linear variable differential transducer.

5. A metering valve assembly according to claim 1 wherein the thermal compensation mechanism maintains a displacement gap between the position sensor and the valve element, the thermal compensation mechanism configured to adjust the width of the displacement gap in relation to changes in fluid temperature.

6. A metering valve assembly according to claim 5 wherein the thermal compensation mechanism is configured to increase the width of the displacement gap in a substantially linear manner as fluid temperature increases over a predetermined temperature range.

7. A metering valve assembly according to claim 6 wherein the predetermined temperature range comprises approximately −

46°

Celsius to approximately 93°

Celsius.

8. A metering valve assembly according to claim 1 wherein the metering valve includes an exponential port.

9. A metering valve assembly according to claim 3 wherein the valve housing comprises a sleeve, and wherein the valve element comprises a piston slidably mounted with the sleeve.

10. A metering valve assembly according to claim 9 wherein the piston is configured to translate along an axis of motion, and wherein the thermal compensation mechanism is configured to adjust the displacement of the sensor input relative to the piston along the axis of motion.

11. A metering valve assembly according to claim 10 wherein the thermal compensation mechanism is configured to expand along the axis of motion as fluid temperature increases.

12. A metering valve assembly according to claim 9 wherein the thermal compensation mechanism is fixedly attached to the sensor input.

13. A metering valve assembly according to claim 1 wherein the thermal compensation mechanism comprises a bi-metallic body.

14. A metering valve assembly according to claim 13 wherein the bi-metallic body comprises a disc.

15. A metering valve assembly for metering a fluid, comprising:

a metering valve, comprising;

a valve sleeve having a flow passage therethrough; and

a valve piston mounted within the valve sleeve and configured to translate therein to control fluid flow through the flow passage;

a position sensor, comprising;

a sensor body coupled to the valve sleeve; and

a sensor input movably coupled to the sensor body; and

a thermal compensation mechanism coupled between the sensor input and the valve piston, the thermal compensation mechanism configured to be heated by the fluid and, when so heated, to move the sensor input away from the metering valve piston.

16. A metering valve assembly according to claim 15 wherein the thermal compensation mechanism comprises a bi-metallic disc.

17. A metering valve assembly according to claim 16 wherein the bi-metallic disc is at least partially concave and increases its concavity as fuel temperature rises.

18. A fuel delivery and control system for supplying a metered amount of fuel to an aircraft engine combustor having an engine controller associated therewith, the fuel delivery and control system comprising:

a fuel source;

a metering valve fluidly coupled between the fuel source and the aircraft engine combustor, the metering valve comprising;

a valve housing having a flow passage therethrough; and

a valve element movably mounted within the valve housing;

a position sensor coupled to the valve element and separated therefrom by a displacement gap, the position sensor further coupled to the engine controller and configured to relate thereto the sensed position of the valve element;

a valve actuator coupled to the valve element and to the engine controller, the valve actuator configured to adjust the position of the valve element in accordance with command signals received from the engine controller; and

a thermal compensation mechanism coupled between the valve element and the position sensor, the thermal compensation mechanism configured to increase the width of the displacement gap as the fuel'"'"'s temperature increases over an operative temperature range.

19. A fuel delivery and control system according to claim 18 wherein the thermal compensation mechanism is configured to expand, as measured along a first axis, as the fuel'"'"'s temperature increases.

20. A fuel delivery and control system according to claim 19 wherein the valve element is configured to translate within the valve housing along a second axis, the second axis being substantially parallel with the first axis.