Excess-flow valve

• US 6,789,561 B2
• Filed: 03/04/2003
• Issued: 09/14/2004
• Est. Priority Date: 08/03/2000
• Status: Expired due to Fees

• Current Assignee: Graham William Osborne
• Original Assignee: Graham William Osborne
• Inventors: Osborne, Graham William
• Primary Examiner(s): Krishnamurthy, Ramesh
• Application Number:
  US10/343,256
• Publication Number:
  US 20030159730A1
• Time in Patent Office: 560 Days
• Field of Search: 137/39, 137/67, 137/68.11, 137/68.14, 137/71, 137/460, 137/498, 137/512.3, 137/517, 137/521, 137/797, 251/58, 251/66, 251/67, 251/89
• US Class Current: 137/71
• CPC Class Codes: F16K 17/34 in which the flow-energy of the flowing medium actuates the closing mechanism
• CPC Class Codes: Y10T 137/1654 Separable valve coupling or conduit
• CPC Class Codes: Y10T 137/1789 Having pressure responsive valve
• CPC Class Codes: Y10T 137/7727 Excessive flow cut-off
• CPC Class Codes: Y10T 137/7785 Valve closes in response to excessive flow
• CPC Class Codes: Y10T 137/7842 Diverse types
• CPC Class Codes: Y10T 137/7869 Biased open
• CPC Class Codes: Y10T 137/7875 Pivoted valves

Abstract

An automatically operating valve for use for example in a forecourt fuel pump has a body (10) defining a flow passage (20) within which is formed a valve seat (22), the body having a weakened zone (16) around the flow passage (20) such that an impact on the body will fracture the body at the weakened zone. A valve member (30) is mounted for movement within the flow passage (20) and is engageable with the valve seat (22) to close the valve. A closing mechanism effects movement of the valve member (30) to its closed position in the event that the body (10) is fractured at the weakened zone. Further, the valve member (30) is configured to move to its closed position under the influence of excessive flow of liquid through the flow passage (20).

Claims

1. An automatically-operating valve having:

a body defining a flow passage, a valve seat provided within the flow passage, and a weakened zone formed in the valve body around the flow passage whereby an impact on the valve body may fracture the valve body at the weakened zone;

a valve member engageable with the valve seat and movable within the flow passage to open and close the valve; and

closing means to effect movement of the valve member to close the valve upon the valve body being fractured at the weakened zone;

the valve member being arranged to move to its closed position under the influence of excessive flow though the flow passage.

2. A valve as claimed in claim 1, wherein there is a spring which biases the valve member to its open position.

3. A valve as claimed in claim 2, wherein the valve member partially obstructs the flow passage when the valve member is in its open position, whereby flow past the valve member in the direction of closing movement of the valve member exerts a force on the valve member tending to close the valve against the action of said spring.

4. A valve as claimed in claim 2, wherein the valve member and seat are in the form of a poppet valve with the valve member mounted for sliding movement towards and away from the valve seat.

5. A valve as claimed in claim 4, wherein the closing means for the valve member comprises a lever external to and pivoted to the valve body which lever is connected to a cam internally of said flow passage, the cam being configured to move the valve member to its closed position against the action of the spring on pivoting movement of the lever.

6. A valve as claimed in claim 2, wherein the valve is in the form of a flap valve having a valve member which co-operates with the valve seat when in its closed position, the valve member being mounted within the flow passage for pivoting movement with respect to the valve body.

7. A valve as claimed in claim 6, wherein said closing means comprises a lever external to and pivoted to the valve body which lever is connected to the valve member internally of said flow passage whereby the valve member is moved to its closed position against the action of the spring on pivoting movement of the lever.

8. A valve as claimed in claim 7, wherein the valve member is articulated to an arm provided internally of the flow passage, which arm is mounted for pivoting movement about the same axis as that of the lever.

9. A valve as claimed in claim 8, wherein said spring comprises a part of a spring-loaded toggle mechanism interconnecting the lever and the arm, whereby movement of the lever through an over-center position of the toggle mechanism drives the valve plate to its closed position, the arm being free to move the valve plate to its closed position against the action of the spring of the toggle mechanism under excessive flow conditions.

10. A valve as claimed in claim 5, wherein there is a second spring which urges the lever to a second position where the valve is closed, the lever being held in a first position where the valve member is free to move between its open and closed positions by a release mechanism which frees the lever should the valve body break at its weakened zone.

11. A valve as claimed in claim 10, wherein the release mechanism includes a frangible link is mounted on the valve body to span the weakened zone, the lever bearing on the frangible link in its first position and being released to move to its second position upon the link breaking.

12. A valve as claimed in claim 11, wherein the frangible link comprises a glass bar or tube spanning the weakened zone and which is clamped to the body each side of said zone.

13. A valve as claimed in claim 1, wherein there is a second valve seat provided within the flow passage on the other side of the weakened zone with respect to the first-mentioned valve seat, there being a second valve member mounted to co-operate with the second valve seat.

14. A valve as claimed in claim 13, wherein the second valve member is spring-urged to engage the second seat so as thereby to form a non-return valve which closes under no-flow or reverse flow conditions, having regard to the normal flow direction through the valve.

15. A valve as claimed in claim 7, wherein there is a second spring which urges the lever to a second position where the valve is closed, the lever being held in a first position where the valve member is free to move between its open and closed positions by a release mechanism which frees the lever should the valve body break at its weakened zone.

16. A valve as claimed in claim 10, wherein there is a second valve seat provided within the flow passage on the other side of the weakened zone with respect to the first-mentioned valve seat, there being a second valve member mounted to co-operate with the second valve seat.

17. A valve as claimed in claim 16, wherein the second valve member is spring-urged to engage the second seat so as thereby to form a non-return valve which closes under no-flow or reverse flow conditions, having regard to the normal flow direction through the valve.