Electrostatically actuated gas valve

• US 20060137749A1
• Filed: 12/29/2004
• Published: 06/29/2006
• Est. Priority Date: 12/29/2004
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Munsterhuis, Sybrandus B.V., Baarda, Gerrit J., Bonne, Ulrich, Wang, Tzu-Yu, Cabuz, Cleopatra, Adams, John T., Cabuz, Eugen I., Kemp, Stephen J.
• Granted Patent: US 7,222,639 B2
• Time in Patent Office: Days
• US Class Current: 137/613
• CPC Class Codes: F16K 31/02 electric F16K31/004 takes precedence; magnetic
• CPC Class Codes: F16K 31/385 the fluid acting on a diaphragm
• CPC Class Codes: F16K 31/402 acting on a diaphragm
• CPC Class Codes: F23N 1/005 using electrical or electromechanical means F23N1/04 - F23N1/10 take precedence
• CPC Class Codes: F23N 2235/18 Groups of two or more valves
• CPC Class Codes: F23N 2235/20 Membrane valves
• CPC Class Codes: F23N 2235/24 Valve details
• CPC Class Codes: Y10T 137/7761 Electrically actuated valve
• CPC Class Codes: Y10T 137/87917 Flow path with serial valves and/or closures

Abstract

A gas valve body with a first flow chamber and, a second flow chamber including and a main valve positioned in line and between the first flow chamber and the second flow chamber. The main valve can be opened by creating a pressure differential across the main valve. An electrostatically controlled pilot valve is provided for controlling the pressure differential across the main valve for “on-ff” operation. The electrostatically controlled pilot valve may also be operated to “modulate” the pressure differential across the main valve along a range of pressure differential values.

Claims

1. A gas valve comprising:

a valve body comprising a gas inlet, a gas outlet, and a conduit connecting the gas inlet and the gas outlet, the conduit comprising a first flow chamber, a second flow chamber and a third flow chamber;

a first electrostatic diaphragm pilot valve disposed between the first flow chamber and the second flow chamber; and

a second electrostatic diaphragm pilot valve disposed between the second flow chamber and the third flow chamber.

2. A gas valve according to claim 1 wherein the first electrostatic diaphragm pilot valve comprises:

a body forming a first diaphragm valve chamber, the first diaphragm valve chamber having a first opposing wall and a second opposing wall;

a diaphragm mounted between the first opposing wall and the second opposing wall, the diaphragm assuming a first position adjacent the first opposing wall when no external force is applied;

a first electrode secured to the second opposing wall; and

a second electrode secured to the diaphragm;

wherein, the diaphragm is electrostatically pulled toward the second opposing wall when a voltage is applied between the first electrode and the second electrode.

3. A gas valve according to claim 2 further comprising:

an inlet port in fluid communication with the first flow chamber and the first diaphragm valve chamber; and

an outlet port in fluid communication with the first diaphragm valve chamber and the second flow chamber when the diaphragm is electrostatically pulled toward the second opposing wall by a voltage applied between the first electrode and the second electrode.

4. A gas valve according to claim 2 further comprising:

an inlet port in fluid communication with the first flow chamber and the first diaphragm valve chamber; and

an outlet port in fluid communication with the first diaphragm valve chamber and the second diaphragm valve chamber when the diaphragm is electrostatically pulled toward the second opposing wall by a voltage applied between the first electrode and the second electrode.

5. A gas valve according to claim 3 wherein the inlet port is disposed through the first opposing wall.

6. A gas valve according to claim 4 wherein the inlet port is disposed through the second opposing wall.

7. A gas valve according to claim 4 further comprising a second inlet port in fluid communication with the first flow chamber and the first diaphragm valve chamber, wherein the inlet is disposed though the first opposing wall and the second inlet is disposed through the second opposing wall.

8. A gas valve according to claim 2 wherein the first opposing wall and the second opposing wall are configured such that a spacing between the first opposing wall and the second opposing wall is smaller near the edge of the first diaphragm valve chamber than near the center of the first diaphragm valve chamber.

9. A gas valve according to claim 1 further comprising a bias member disposed between the diaphragm and the second opposing wall.

10. A gas valve according to claim 2 further comprising an aperture disposed through the diaphragm.

11. A gas valve according to claim 10 wherein the aperture is disposed adjacent the second opposing wall as the diaphragm is electrostatically pulled toward the second opposing wall.

12. A gas valve according to claim 2,wherein the second electrostatic diaphragm pilot valve comprises:

a body forming a second diaphragm valve chamber, the second diaphragm valve chamber having a first opposing wall and a second opposing wall;

a diaphragm mounted between the first opposing wall and the second opposing wall, the diaphragm assuming a first position adjacent the first opposing wall when no external force is applied;

a first electrode secured to the second opposing wall; and

a second electrode secured to the diaphragm;

wherein, the diaphragm is electrostatically pulled toward the second opposing wall when a voltage is applied between the first electrode and the second electrode.

13. A gas valve according to claim 12 further comprising:

an inlet port in fluid communication with the second flow chamber and the second diaphragm valve chamber; and

an outlet port in fluid communication with the second diaphragm valve chamber and the third flow chamber when the diaphragm is electrostatically pulled toward the second opposing wall by a voltage applied between the first electrode and the second electrode.

14. A gas valve according to claim 12 further comprising:

an inlet port in fluid communication with the first diaphragm valve chamber and the second diaphragm valve chamber; and

an outlet port in fluid communication with the second diaphragm valve chamber and the third flow chamber only when the diaphragm is electrostatically pulled toward the second opposing wall by a voltage applied between the first electrode and the second electrode.

15. A gas valve according to claim 13 wherein the inlet port is disposed through the first opposing wall.

16. A gas valve according to claim 14 wherein the inlet port is disposed through the first opposing wall.

17. A gas valve according to claim 14 further comprising a second inlet port in fluid communication with the second flow chamber and the second diaphragm valve chamber, wherein the inlet is disposed though the first opposing wall and the second inlet is disposed through the second opposing wall.

18. A gas valve according to claim 12 wherein the first opposing wall and the second opposing wall are configured such that a spacing between the first opposing wall and the second opposing wall is smaller near the edge of the second diaphragm valve chamber than near the center of the second diaphragm valve chamber.

19. A gas valve according to claim 12 further comprising a bias member disposed between the diaphragm and the second opposing wall.

20. A gas valve according to claim 12 further comprising an aperture disposed through the diaphragm.

21. A gas valve according to claim 1 wherein the valve body further comprises an electrostatic diaphragm pressure sensor in fluid communication with the gas outlet.

22. A gas valve according to claim 1 wherein the valve body further comprises a particulate matter trap in fluid communication with the first or second electrostatic valve.

23. A gas valve comprising:

a valve body comprising a gas inlet, a gas outlet, and a conduit connecting the gas inlet and the gas outlet, the conduit comprising a first flow chamber, a second flow chamber and a third flow chamber;

a first electrostatic diaphragm valve disposed between the first flow chamber and the second flow chamber;

a second electrostatic diaphragm valve disposed between the second flow chamber and the third flow chamber; and

a pressure sensor in fluid communication with the gas outlet.

24. A gas valve according to claim 23 wherein the pressure sensor is a diaphragm type pressure sensor having a diaphragm forming a pressure chamber with an opposing wall, the diaphragm having a diaphragm electrode and the opposing wall having an opposing wall electrode.

25. A gas valve according to claim 23 wherein the diaphragm electrode and the opposing wall electrode are coupled to a controller, and wherein the controller is adapted to determine a measure of capacitance between the diaphragm electrode and the opposing wall electrode.

26. A gas valve according to claim 25 wherein the diaphragm of the pressure sensor deflects toward the opposing wall when a pressure is applied via the gas outlet, which changes the capacitance between the diaphragm electrode and the opposing wall electrode.

27. A gas valve according to claim 26 wherein the opposing wall has a curved shape.

28. A gas valve according to claim 26 wherein the opposing wall has a linear shape.

29. A gas valve according to claim 26 wherein the opposing wall has a compound linear shape.

30. A gas valve according to claim 26 wherein the opposing wall has a shape that provides a relatively linear relationship between an applied pressure via the gas outlet and the capacitance between the diaphragm electrode and the opposing wall electrode.

31. A gas valve according to claim 26 wherein the pressure sensor includes two or more pressure sensors, each having a different pressure versus capacitance curve.

32. A gas valve according to claim 31 wherein at least one of the pressure sensors has a measuring pressure range different from that of another one of the pressure sensors.

33. A gas valve according to claim 23 wherein the valve body further comprises a particulate matter trap in fluid communication with the first or second electrostatic valve.

34. A gas valve comprising:

a first flow chamber;

a second flow chamber;

a first main valve positioned between the first flow chamber and the second flow chamber, wherein the first main valve is opened by a pressure differential across the first main valve; and

a first electrostatically controlled valve for controlling the pressure differential across the first main valve.

35. The gas valve of claim 34 further comprising:

a third flow chamber;

a second main valve positioned between the second flow chamber and the third flow chamber, wherein the second main valve is opened by a pressure differential across the second main valve; and

a second electrostatically controlled valve for controlling the pressure differential across the second main valve.

36. The gas valve of claim 35 wherein the second electrostatically controlled valve is in fluid communication with the first electrostatically controlled valve.

37. The gas valve of claim 34 wherein the first electrostatically controlled valve is adapted to control the pressure differential across the first main valve along a range of pressure differential values.

38. The gas valve of claim 35 wherein the second electrostatically controlled valve is adapted to control the pressure differential across the second main valve along a range of pressure differential values.

39. A gas valve according to claim 34 wherein the gas valve further comprises a particulate matter trap in fluid communication with the first electrostatic valve.