Flow control valves

• US 7,128,086 B2
• Filed: 05/24/2005
• Issued: 10/31/2006
• Est. Priority Date: 06/24/2003
• Status: Active Grant

• Current Assignee: Flow Control Industries, Inc.
• Original Assignee: Flow Control Industries, Inc.
• Inventors: Skoglund, Paul K., Trueblood, Ben, Kirchner, Mark W.
• Primary Examiner(s): Hepperle, Stephen M.
• Application Number:
  US11/136,767
• Publication Number:
  US 20050211305A1
• Time in Patent Office: 525 Days
• Field of Search: 137/500, 137/494, 137/501, 137/502, 137/503, 137/460
• US Class Current: 137/501
• CPC Class Codes: F16K 31/363 the fluid acting on a piston F16K31/38 takes precedence
• CPC Class Codes: F16K 31/383 the fluid acting on a piston
• CPC Class Codes: G05D 7/0133 within the flow-path
• CPC Class Codes: Y10T 137/7787 Expansible chamber subject to differential pressures
• CPC Class Codes: Y10T 137/7788 Pressures across fixed choke
• CPC Class Codes: Y10T 137/7834 Valve seat or external sleeve moves to open valve

Abstract

In one embodiment, a flow control valve includes a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity with first and second chambers. The valve further includes a hollow piston disposed in the first chamber and a seal separating the first and second chambers. The seal has a section within the piston that is exposed to the fluid in the first chamber. The section of the seal defines a first effective area. The valve also includes a biasing member configured to urge the piston, and a reference pressure passageway in fluid communication with the inlet and the second chamber. The valve can further include a piston seat that has a second inner effective area at least approximately equal to the first inner effective area.

Claims

1. A valve, comprising:

a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity intersecting the flow passageway, the cavity having a first chamber and a second chamber, the second chamber having a generally hollow configuration;

a piston assembly including a hollow piston body, a support member coupled to the hollow piston body, and a poppet coupled to the support member, the hollow piston body being disposed in the second chamber, the support member and the poppet being disposed in the first chamber;

a seal having a section separating the first and second chambers, the section defining a first effective inner area;

a biasing member configured to urge the hollow piston body toward the first chamber;

a reference pressure passageway in fluid communication with the outlet and the second chamber; and

a piston seat positioned to selectively engage the poppet, the piston seat enclosing a second effective inner area at least approximately equal to the first effective inner area;

wherein the hollow piston body has an inner wall defining a third inner area greater than or egual to the first effective inner area.

3. The valve of claim 1 wherein the seal is a diaphragm seal coupled to the valve body and configured to engage the hollow piston body, the diaphragm seal having a first convolution radially outside the hollow piston body and a second convolution radially inside the hollow piston body.

4. The valve of claim 1 wherein the hollow piston body has a generally annular configuration.

6. The valve of claim 1 wherein the reference pressure passageway includes a restriction to limit the fluid flow rate between the second chamber and the outlet.

7. The valve of claim 1 wherein the section of the seal is exposed to fluid in the first and second chambers.

2. A valve, comprising:

a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity intersecting the flow passageway, the cavity having a first chamber and a second chamber, the second chamber having a generally hollow configuration;

a piston assembly including a hollow piston body, a support member coupled to the hollow piston body, and a poppet coupled to the support member, the hollow piston body being disposed in the second chamber, the support member and the poppet being disposed in the first chamber;

a seal having a section separating the first and second chambers, the section defining a first effective inner area;

a biasing member configured to urge the hollow piston body toward the first chamber;

a reference pressure passageway in fluid communication with the outlet and the second chamber; and

a piston seat positioned to selectively engage the poppet, the piston seat enclosing a second effective inner area at least approximately equal to the first effective inner area;

wherein the seal is a diaphragm seal having central and perimeter portions coupled to the valve body and an annular portion between the central and perimeter portions positioned to contact the hollow piston body.

8. The valve of claim 2 wherein the diaphragm seal includes a first convolution radially outside the hollow piston body and a second convolution radially inside the hollow piston body.

9. The valve of claim 2 wherein the hollow piston body has a generally annular configuration.

10. The valve of claim 2 wherein the reference pressure passageway includes a restriction to limit the fluid flow rate between the second chamber and the outlet.

11. The valve of claim 2 wherein the section of the seal is exposed to fluid in the first and second chambers.

5. A valve, comprising:

a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity intersecting the flow passageway, the cavity having a first chamber and a second chamber, the second chamber having a generally hollow configuration;

a piston assembly including a hollow piston body, a support member coupled to the hollow piston body, and a poppet coupled to the support member, the hollow piston body being disposed in the second chamber, the support member and the poppet being disposed in the first chamber;

a seal having a section separating the first and second chambers, the section defining a first effective inner area;

a biasing member configured to urge the hollow piston body toward the first chamber;

a reference pressure passageway in fluid communication with the outlet and the second chamber; and

a piston seat positioned to selectively engage the poppet, the piston seat enclosing a second effective inner area at least approximately equal to the first effective inner area;

wherein the seal includes a first seal between the outside of the hollow piston body and the valve body, and wherein the valve further comprises a second seal between the inside of the hollow piston body and the valve body.

12. The valve of claim 5 wherein the first seal includes a first convolution radially outside the hollow piston body and the second seal includes a second convolution radially inside the hollow piston body.

13. The valve of claim 5 wherein the hollow piston body has a generally annular configuration.

14. The valve of claim 5 wherein the reference pressure passageway includes a restriction to limit the fluid flow rate between the second chamber and the outlet.

15. The valve of claim 5 wherein the first and second seals are exposed to fluid in the first and second chambers.