Check valve for micro electro mechanical structure devices

• US 6,834,671 B2
• Filed: 12/22/2003
• Issued: 12/28/2004
• Est. Priority Date: 07/26/2001
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Cotte, John Michael, Volant, Richard P., Moreau, Wayne Martin, Simons, John P., Taft, Charles J., McCullough, Kenneth John
• Primary Examiner(s): Krishnamurthy, Ramesh
• Application Number:
  US10/743,155
• Publication Number:
  US 20040134538A1
• Time in Patent Office: 372 Days
• Field of Search: 137/496, 137/511, 137/513.7, 137/528
• US Class Current: 137/528
• CPC Class Codes: F15C 5/00 Manufacture of fluid circuit elements; Manufacture of assemblages of such elements integrated circuits
• CPC Class Codes: F16K 15/023 the valve member consisting only of a predominantly disc-shaped flat element
• CPC Class Codes: F16K 2099/0094 Micropumps
• 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 99/0005 Lift valves
• CPC Class Codes: F16K 99/0007 of cantilever type
• CPC Class Codes: F16K 99/0057 the fluid being the circulating fluid itself, e.g. check valves
• CPC Class Codes: Y10T 137/7783 Valve closes in responses to reverse flow
• CPC Class Codes: Y10T 137/7849 Bypass in valve casing
• CPC Class Codes: Y10T 137/7904 Reciprocating valves

Abstract

A check valve for micro electro mechanical structure devices (MEMS), and in particular pertains to a check valve which is adapted to be employed in connection with micro electro mechanical structure devices which are intended to be employed with supercritical fluids constituting working fluids. In a preferred embodiment, the check valve is equipped with a bypass channel including a freely moveable plug structure which, in the open position of the valve enables the ingress of supercritical fluids under high superatmospheric pressures, and subsequent to the filling of the system, let down to atmospheric pressure, causes the plug to be moved into a permanent valve-closed position.

Claims

1. A check valve for micro electromechanical structure devices, said check valve being connectable to a supercritical fluid hydraulic system being rapidly charged with pressurized fluid under superatmospheric pressures and comprising:

a) a valve body having a fluid inlet conduit and a fluid outlet conduit;

b) a valve chamber of a larger internal diameter than said conduits being interposed between said fluid inlet and fluid outlet conduit in fluid flow communication with said fluid inlet and fluid outlet conduits, a valve seat being formed between said valve chamber and an adjoining end of said fluid input conduit;

c) a fluid bypass channel connecting said fluid outlet conduit and said valve chamber;

d) and a freely movable valve member being located in said valve chamber and having an external diameter in slidable contact with the internal diameter of said valve chamber, said valve member being axially displaced into a first valve-open position within said chamber facilitating an unobstructed flow by said pressurized fluid from said inlet conduit into said bypass channel through said valve chamber for charging said system, and responsive to a letdown of pressure upon said system having been charged, said valve member being axially displaced within said valve chamber into contact with said valve seat in a second valve-closing position so as to inhibit fluid flow through said check valve and seal said supercritical fluid hydraulic system.

2. A check valve as claimed in claim 1, wherein said valve is self-sealing responsive to said valve member being moved into contact with said valve seat.

3. A check valve as claimed in claim 1, wherein said valve comprises a permanent component of said system upon pressure letdown thereof in that said valve member is maintained in a sealing relationship with said valve seat.

4. A check valve as claimed in claim 1, wherein said valve member comprises a plug member which is slidable within said valve chamber between said first position in which said bypass channel enables fluid flow communication between said valve chamber and said fluid outlet conduit to facilitate filling said system and said second position in sealing engagement with said valve seat so as to inhibit fluid flow through said check valve.

5. A check valve as claimed in claim 1, wherein said hydraulic system is a component of a heating and cooling or pumping arrangement for supercritical fluids.

6. A check valve as claimed in claim 1, wherein said fluid bypass channel comprises a conduit of an internal diameter which is approximately the size of the internal diameters of each of said fluid inlet and outlet conduits.