Microvalve

• US 6,592,098 B2
• Filed: 10/18/2001
• Issued: 07/15/2003
• Est. Priority Date: 10/18/2000
• Status: Expired due to Fees

• Current Assignee: The Research Foundation for The State University of New York (State University of New York)
• Original Assignee: State University of New York
• Inventors: Wong, Robert P., Cassar, Thomas J., Kao, Imin
• Primary Examiner(s): Hirsch, Paul J.
• Application Number:
  US09/982,722
• Publication Number:
  US 20020043638A1
• Time in Patent Office: 635 Days
• Field of Search: 251/11, 251/129.01
• US Class Current: 251/129.01
• CPC Class Codes: F15C 5/00 Manufacture of fluid circuit elements; Manufacture of assemblages of such elements integrated circuits
• CPC Class Codes: F16K 2099/0074 using photolithography, e.g. etching
• CPC Class Codes: F16K 99/0001 Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0011 Gate valves or sliding valves
• CPC Class Codes: F16K 99/0015 Diaphragm or membrane valves
• CPC Class Codes: F16K 99/0036 operated by temperature variations
• CPC Class Codes: F16K 99/0046 using magnets
• CPC Class Codes: F16K 99/0048 using piezoelectric means
• CPC Class Codes: F16K 99/0051 using electrostatic means
• CPC Class Codes: Y10T 137/7771 Bi-directional flow valves
• CPC Class Codes: Y10T 137/87676 With flow control

Abstract

An improved microvalve device is configured to provide a more robust and durable operation to withstand the demands of various operating environments. The microvalve may comprise a valve seat and a diaphragm, with the diaphragm operated by an external actuator device, such as a bladder, through various mechanisms of actuation, such as direct and indirect mechanisms, that are separate from the microvalve. Through use of the various mechanisms of actuation, the actuator device is configured to apply forces on the diaphragm to suitably move the diaphragm to open and close the microvalve. The valve seat and diaphragm can be configured to provide the microvalve with a plurality of openings configured to permit flow thereinbetween. In addition, the microvalve may be configured to facilitate uni-directional or bi-directional flow. Further, a plurality of microvalves can be cascaded together in a parallel and/or series configuration, with each valve having similar or different flow characteristics, and being selectively operated. The microvalve can also include a combination gate valve configuration and a bladder configuration to provide high frequency response characteristics in addition to stability and reduction in leak flow.

Claims

1. A microvalve system for providing robust and durable operation within a MEMS environment, said microvalve comprising:

a valve seat comprised of a substrate material;

a diaphragm configured with said valve seat to define a passageway, said diaphragm comprised of said substrate material and having a boss component, said boss component having a protruding portion configured for closure of said passageway when said boss component is in juxtaposition with said valve seat; and

an external actuation device being adjacent to said diaphragm and having an internal bias pressure, said external actuation being configured to urge said diaphragm towards said valve seat to regulate flow of fluid within said passageway; and

an actuation mechanism for operating said external actuation device based on said bias pressure to facilitate regulation of flow fluid within said passageway.

2. The microvalve system according to claim 1, wherein said external actuation device comprises a bladder device having a fluid contained within, said bladder device being configured for expanding and contracting to urge movement of said diaphragm to regulate flow of said passageway.

3. The microvalve system according to claim 1, wherein said microvalve system is configured for bi-directional flow.

4. The microvalve system according to claim 1, wherein said valve seat comprises at least one orifice configured for allowing one of an inflow or outflow of fluid through said at least one orifice.

5. The microvalve system according to claim 4, wherein said valve seat comprises at least two orifices configured for an inflow of fluid, and at least one orifice configured for an outflow of fluid, and said passageway is defined by said valve seat, said diaphragm, and said orifices.

6. The microvalve system according to claim 1, wherein said valve seat comprises at least one orifice configured for allowing bi-directional flow of fluid through said at least one orifice.

7. The microvalve system according to claim 1, wherein said valve seat further comprises a boss component having a protruding portion configured for regulating flow of fluid in said passageway in conjunction with said boss component of said diaphragm.

8. The microvalve system according to claim 1, wherein said boss component comprises a trapezoid configuration for facilitating a reduction in non-linear characteristics through less obstruction of fluid flowing within said passageway.

9. The microvalve system according to claim 1, wherein said microvalve system comprises a plurality of microvalves cascaded in a parallel manner, each of said microvalves comprising at least one of said valve seats and said diaphragms.

10. The microvalve system according to claim 9, wherein said microvalve system comprising n microvalves having a flow rate f comprises a total flow rate of nf.

11. The microvalve system according to claim 9, wherein said plurality of microvalves are configured with a single external actuator device to facilitate movement of each diaphragm within said plurality of microvalves.

12. The microvalve system according to claim 1, wherein said microvalve system comprises a plurality of microvalves cascaded in a series manner, each of said microvalves comprising at least one of said valve seats, said diaphragms, and said external actuation devices.

13. The microvalve system according to claim 12, wherein said actuation mechanism comprises a direct means of actuation including one of an electrostatic, an electromagnetic, and a piezoelectric actuation.

14. The microvalve system according to claim 1, wherein said actuation mechanism comprises an indirect means of actuation.

15. The microvalve system according to claim 1, wherein said fluid comprises at least one of a gas, a liquid and a superheated fluid including steam.

16. The microvalve system according to claim 15, wherein said indirect means of actuation comprises one of thermal actuation.

17. The microvalve system according to claim 1, wherein said microvalve system further comprises a gate valve configuration to facilitate a high frequency response, stability and a reduction in leak flow.

18. The microvalve system according to claim 17, wherein said gate valve is coupled between one end of said valve seat and said diaphragm to further regulate fluid flow within said passageway.

19. The microvalve system according to claim 17, wherein said valve seat comprises at least one orifice, and said gate valve is configured with said at least one orifice of said valve seat to further regulate fluid flow within said passageway.

20. A microvalve for providing regulation of flow within a MEMS application, said microvalve comprising:

a valve seat comprised of a substrate material;

a diaphragm configured with said valve seat to define a passageway, said diaphragm comprised of said substrate material and having a boss component, said boss component having a protruding portion configured for closure of said passageway when said boss component is in juxtaposition with said valve seat; and

an actuation device being adjacent to said diaphragm and having an internal bias pressure, said actuation device being configured to urge said diaphragm towards said valve seat to regulate flow of fluid within said passageway, said actuation device being configured for actuation by external actuation mechanisms.

21. The microvalve according to claim 20, wherein said actuation device comprises a bladder device having a fluid contained within, said bladder device being configured for expanding and contracting to urge movement of said diaphragm to regulate flow of said passageway.

22. The microvalve according to claim 20, wherein said actuation device comprises a thermal-pneumatic actuator device to urge movement of said diaphragm to regulate flow of said passageway.

23. The microvalve according to claim 20, wherein said microvalve is configured for bi-directional flow.

24. The microvalve according to claim 20, wherein said valve seat comprises at least one orifice configured for allowing one of an inflow or outflow of fluid through said at least one orifice.

25. The microvalve according to claim 20, wherein said valve seat further comprises a boss component having a protruding portion configured for regulating flow of fluid in said passageway in conjunction with said boss component of said diaphragm.

26. The microvalve according to claim 20, wherein said actuation device can be actuated by a direct means of actuation comprising one of an electrostatic, an electromagnetic, and a piezoelectric actuation.

27. The microvalve according to claim 20, wherein said actuation device can be actuated by an indirect means of actuation comprising one of thermal actuation.

28. The microvalve according to claim 20, wherein said boss component comprises a trapezoid configuration having at least one side with less than a 50°

slope from a planar surface of said diaphragm to increase linear characteristics of said microvalve.

29. The microvalve according to claim 20, wherein said microvalve further comprises a latch and release device configured to lock said diaphragm in a fixed regulation position to reduce an impact of back pressure upon said diaphragm.

30. The microvalve according to claim 20, wherein said microvalve further comprises a gate valve to facilitate a high frequency response, stability and a reduction in leak flow.

31. The microvalve according to claim 30, wherein said gate valve comprises a metal flap.

32. The microvalve according to claim 30, wherein said gate valve comprises a shutter configuration.

33. The microvalve according to claim 30, wherein said gate valve is coupled between one end of said valve seat and said diaphragm to further regulate fluid flow within said passageway.

34. The microvalve according to claim 30, wherein said valve seat comprises at least one orifice, and said gate valve is configured with said at least one orifice of said valve seat to further regulate fluid flow within said passageway.

35. The microvalve according to claim 20, wherein said fluid comprises one of a gas and a liquid.

36. The microvalve according to claim 20, wherein said fluid comprises a superheated fluid including steam.