Variable stiffness flow control valve

• US 20060000459A1
• Filed: 05/24/2005
• Published: 01/05/2006
• Est. Priority Date: 05/28/2004
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Ford Motor Company
• Inventors: Slocum, Alexander H., Freeman, David C., Kabat, Daniel
• Granted Patent: US 7,370,645 B2
• Time in Patent Office: Days
• US Class Current: 123/574
• CPC Class Codes: F01M 13/0011 Breather valves
• CPC Class Codes: F02B 25/06 the cylinder-head ports being controlled by working pistons, e.g. by sleeve-shaped extensions thereof
• CPC Class Codes: F02B 25/22 by forming air cushion between charge and combustion residues
• CPC Class Codes: F02M 25/08 adding fuel vapours drawn from engine fuel reservoir electrical control of purge system F02D41/003
• CPC Class Codes: F16K 15/144 the closure elements being fixed along all or a part of their periphery
• CPC Class Codes: F16K 27/0209 Check valves or pivoted valves
• CPC Class Codes: Y10T 137/7888 With valve member flexing about securement
• CPC Class Codes: Y10T 137/7891 Flap or reed

Abstract

A flow control valve is provided. According to one aspect of this disclosure, the flow control valve includes a valve element and a support element. The valve element is configured to deflect responsive to a change in pressure difference across the valve element. The support element cooperates with the valve element to present an effective flow-through area that changes as the valve element deflects. The amount of relative engagement between the valve element and the support element changes as the valve element deflects. External vibration causes the valve element to vibrate to reduce stiction or ice buildup.

Claims

1. A flow control valve, comprising:

a flow controlling valve configured to deflect from a generally planar posture to an increasingly nonplanar posture responsive to a relative increase in pressure difference and flow across the valve element; and

a support element including;

a support structure supporting the valve element in its undeflected state;

at least a first contact surface recessed from the support structure and configured to engage the valve element only when the valve element is deflected; and

a flow passage;

wherein an effective flow-through volume through the at least one opening and the flow passage decreases as deflection of the valve element increases.

2. The flow control valve of claim 1, wherein the first contact surface increases the stiffness of the valve element when the first contact surface engages the valve element.

3. The flow control valve of claim 1, wherein engagement of the valve element by the first contact surface affects deflection characteristics of the valve element.

4. The flow control valve of claim 3, wherein engagement of the valve element by the first contact surface limits deflection of the valve element.

5. The flow control valve of claim 4, wherein engagement of the valve element by the first contact surface nonlinearly limits deflection of the valve element.

6. The flow control valve of claim 1, wherein the at least first contact surface engages a discrete segment of the valve element.

7. The flow control valve of claim 1, wherein the at least first contact surface engages progressively more of the valve element as deflection of the valve element increases.

8. The flow control valve of claim 1, further including at least a second contact surface recessed from the first contact surface and configured to engage the valve element only when the valve element is deflected more than is necessary for the first contact surface to engage the valve element.

9. The flow control valve of claim 1, wherein the valve element is a one-piece disk.

10. The flow control valve of claim 9, wherein the one piece disk includes support arms of desired stiffness extending from the surface that covers the flow passage.

11. The flow control valve of claim 1, wherein the support element is a static support element.

12. The flow control valve of claim 1, wherein the support element is a one-piece support element.

13. The flow control valve of claim 12, wherein the support element includes support arms of desired stiffness extending from the support element.

14. The flow control valve of claim 1, wherein the valve element responds to flow across the valve with flow induced vibrations that limit freezing of the valve element.

15. The flow control valve of claim 9, wherein the one piece disk contains at least one hole, of size substantially smaller than the flow passage located around or within the circumference of the disk to reduce audible vibration caused by the flow through the valve.

16. The flow control valve of claim 9, wherein material is removed from the circumference of the one piece disk to reduce audible vibration caused by the flow through the valve.

17. The flow control valve of claim 9, wherein material is removed from the circumference of the one piece disk in small cuts to reduce audible vibration caused by the flow through the valve.

18. The flow control valve of claim 9, wherein the material at the outer circumference of the one piece disk has been embossed or deformed to reduce audible vibration caused by the flow through the valve.

19. The flow control valve of claim 1, further comprising a top, wherein the support element and the top collectively house the valve element and are configured to be operatively interposed between a crankcase and an intake manifold in an engine.

20. The flow control valve of claim 19, wherein the valve element is comprised of a one piece disk having at least one mass attached to the end of a cantilevered beam attached to the disk.

21. The flow control valve of claim 20, wherein the mass is formed by folding a part of the flat monolithic material making up the valve element.

22. The flow control valve of claim 20, wherein the cantilevered beam oscillates in response to external excitation.

23. The flow control valve of claim 21, wherein the cantilevered beam oscillates in response to external excitation.

24. The flow control valve of claim 22, wherein the oscillation of the cantilevered beam prevents stiction or ice buildup.

25. A flow control valve, comprising:

a valve element configured to deflect responsive to a change in pressure difference across the valve element; and

a support element that cooperates with the valve element to present an effective flow-through area that changes as the valve element deflects, wherein an amount of relative engagement between the valve element and the support element changes as the valve element deflects.

26. The flow control valve of claim 25, wherein a stiffness of the valve element changes as the amount of relative engagement between the valve element and the support element changes.

27. The flow control valve of claim 25, wherein a stiffness of the valve element increases as the amount of relative engagement between the valve element and the support element increases.

28. The flow control valve of claim 25, wherein the support element includes at least a first contact surface configured to variably engage, and thereby effectively stiffen, the valve element.

29. The flow control valve of claim 28, wherein the at least first contact surface engages progressively more of the valve element as deflection of the valve element changes.

30. The flow control valve of claim 28, wherein the at least first contact surface engages a discrete segment of the valve element.

31. The flow control valve of claim 28, further comprising a support structure supporting the valve element, wherein the first contact surface is recessed from the support structure and only engages the valve element when the valve element is deflected.

32. The flow control valve of claim 28, further including at least a second contact surface configured to engage, and thereby effectively stiffen, the valve element only when valve element deflection has changed more than is necessary for the first contact surface to engage the valve element.

33. The flow control valve of claim 25, wherein changing relative engagement between the support element and the valve element changes linearity of an effective stiffness of the valve element.

34. The flow control valve of claim 25, wherein the valve element is configured to deflect from a generally planar posture to an increasingly nonplanar posture responsive to a relative increase in pressure difference across the valve element.

35. The flow control valve of claim 25, wherein the valve element is a one-piece disk.

36. The flow control valve of claim 25, wherein the support element is a static support element.

37. The flow control valve of claim 25, wherein the support element is a one-piece support element.

38. The flow control valve of claim 25, wherein the valve element responds to high frequency vortex shedding with high frequency vibrations that limit freezing of the valve element.

39. The flow control valve of claim 25, further comprising a top, wherein the support element and the top collectively house the valve element and are configured to be operatively interposed between a crankcase and an intake manifold in an engine.

40. A flow control valve, comprising:

means for conveying a fluid; and

means for restricting conveyance of the fluid through the means for conveying a fluid, wherein the means for restricting conveyance of the fluid variably engages the means for conveying a fluid, thereby causing the means for restricting conveyance of the fluid to change restriction properties.

41. The flow control valve of claim 40, where said valve is coupled between a crankcase and an intake manifold of an engine.

42. The flow control valve of claim 40, where said valve can be mounted independently of gravity, allowing installation in any orientation.

43. The flow control valve of claim 42, where said valve is installed in close proximity to the exhaust manifold of an engine, using its heat to prevent freezing.

44. An engine, comprising:

a crankcase;

an intake manifold; and

a flow control valve operatively interposed between the crankcase and the intake manifold, wherein the flow control valve includes;

a valve element configured to deflect responsive to a change in pressure difference between the intake manifold and the crankcase; and

a support element that cooperates with the valve element to present an effective flow-through area that changes as the valve element deflects, wherein an amount of relative engagement between the valve element and the support element changes as the valve element deflects.

45. An engine, comprising:

a crankcase;

an intake manifold; and

a flow control valve operatively interposed between the crankcase and the intake manifold, wherein the flow control valve includes;

a valve element including at least one opening and configured to deflect from a generally planar posture to an increasingly nonplanar posture responsive to a relative increase in pressure difference across the valve element; and

a support element including;

a support structure supporting the valve element;

at least a first contact surface recessed from the support structure and configured to engage the valve element only when the valve element is deflected; and

a flow passage;

wherein an effective flow-through volume through the at least one opening and the flow passage decreases as deflection of the valve element increases.

46. An engine, comprising:

a crankcase;

an intake manifold; and

a flow control valve operatively interposed between the crankcase and the intake manifold, wherein the flow control valve includes;

a one-piece spring element having a flow-blocking surface that variably restricts flow between the crankcase and the intake manifold as the one-piece spring element deflects responsive to pressure differences between the crankcase and the intake manifold.

47. An engine, comprising:

a crankcase;

an intake manifold; and

a flow control valve operatively interposed between the crankcase and the intake manifold, wherein the flow control valve includes;

a generally disk-shaped spring element having a flow-blocking surface that variably restricts flow between the crankcase and the intake manifold.