Integral pressure sensor

• US 5,284,061 A
• Filed: 09/21/1992
• Issued: 02/08/1994
• Est. Priority Date: 09/21/1992
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Jackson, Allan D., Seeley, Eric E.
• Primary Examiner(s): Chilcot, Jr., Richard E.
• Assistant Examiner(s): FELBER, JOSEPH LEON
• Application Number:
  US07/948,502
• Time in Patent Office: 505 Days
• Field of Search: 73/40, 73/49.2, 73/49.3, 73/52, 73/745, 73/746, 73/753, 73/146.5, 73/146.8, 73/DIG. 3, 340/451, 340/611, 340/614, 340/626, 200/81 R, 200/81.9 M, 200/82 E, 338/32 H, 338/36, 338/42, 338/47
• US Class Current: 73/746
• CPC Class Codes: G01L 19/12 Alarms or signals
• CPC Class Codes: Y10S 73/03 Hall effect

Abstract

An integral pressure sensor for a pressurized vessel, including a housing, a core element, a seal and a spring. This combination is disposed on the interior of the pressurized vessel. The core element is preferably a magnetic element or a steel ball which moves in the housing under the effect of the vessel pressure, and the chamber or housing pressure. The spring and seal combination together with the core element, function to trap a specified volume of the pressurized medium in the chamber when the vessel is initially pressurized. When the pressurized vessel leaks, the trapped pressure within the chamber exceeds the vessel pressure thereby causing the core element to move. The position or presence of the core element is detected using a detecting device such as a Hall-effect device or another magnetic device.

Claims

1. An integral pressure sensor for a pressurized vessel comprising:

a housing defining an interior chamber and an opening, said housing disposed in the interior of said vessel;

a core element movably disposed in said interior chamber, said core element moving in said interior chamber under the effect of a differential pressure between said vessel pressure and said interior chamber pressure; and

a means to trap said vessel pressure in said interior chamber, said means to trap being sealably disposed in said interior chamber and in operative association with said core element so that said interior chamber pressure is isolated from said vessel pressure.

2. An integral pressure sensor as set forth in claim 1 further comprising a means for detecting the position of said core element, said means for detecting being externally disposed on said pressurized vessel proximate said housing.

3. An integral pressure sensor as set forth in claim 1 wherein the means to trap said vessel pressure in said interior chamber further comprises:

a sealing device disposed in said housing and proximate said opening; and

an elastic force member attached within said housing and further in contact with said core element, said elastic force member biased such that the core element comes in contact with said sealing device to sealably isolate the chamber pressure from said vessel pressure.

4. An integral pressure sensor as set forth in claim 1 wherein said core element is a magnetic element.

5. An integral pressure sensor as set forth in claim 1 wherein said core element is a magnetic ball.

6. An integral pressure sensor as set forth in claim 1 wherein said core element is a steel ball.

7. An integral pressure sensor as set forth in claim 1 wherein said opening of said housing further defines an open end.

8. An integral pressure sensor as set forth in claim 1 wherein said sealing device is an O-ring seal.

9. An integral pressure sensor as set forth in claim 3 wherein said elastic force member is a spring.

10. An integral pressure sensor as set forth in claim 2 wherein said means for detecting the movement of said core element is a Hall-Effect device.

11. An integral pressure sensor for a pressurized vessel comprising:

a housing defining an upper chamber, a lower chamber and an opening, said housing attached proximate to an interior surface of said pressurized vessel;

a core element movably disposed in said upper and lower chambers, said core element moving in said upper and lower chambers under the effect of a vessel pressure and an upper chamber pressure;

a means to trap said vessel pressure in said upper chamber, said means to trap being sealably disposed in said housing and in operative association with said core element so that said upper chamber pressure is isolated from said vessel pressure; and

a detector shield disposed on said housing proximate the opening and further covering a portion of said housing.

12. An integral pressure sensor as set forth in claim 11 further comprising a means for detecting the presence of said core element in said upper chamber, said means for detecting externally disposed on said pressurized vessel proximate said upper chamber.

13. An integral pressure sensor as set forth in claim 11 further comprising a reset spring disposed in said lower chamber.

14. An integral pressure sensor as set forth in claim 11 wherein the means to trap said vessel pressure in said upper chamber further comprises:

a sealing device disposed in said housing and further disposed between said upper and lower chambers; and

an elastic force member attached within said housing and further in contact with said core element, said elastic force member biased such that the core element comes in contact with said sealing device to sealably isolate the chamber pressure from said vessel pressure.

15. A method for detecting leaks in a pressurized vessel, comprising the steps of:

attaching an integral pressure sensing device to an interior surface of said vessel, said integral pressure sensing device comprising a housing which defines an interior chamber and an opening;

a core element disposed in said interior chamber;

a sealing device disposed in said housing and proximate said opening; and

an elastic force member attached within said housing and further in contact with said core element, said elastic force member biased such that the core element comes in contact with said sealing device to sealably isolate the chamber from said vessel;

pressurizing said vessel with a pressurized medium;

trapping a specified volume of said pressurized medium in said interior chamber so that said core element together with said elastic force member and said sealing device form an impermeable seal between said interior chamber and said vessel when said interior chamber pressure is equal to said vessel pressure, and further so that said core element is ejected from said interior chamber when said interior chamber pressure exceeds said vessel pressure due to a leak in said pressurized vessel; and

placing a detector on an exterior surface of said pressurized vessel proximate said housing so that the presence or absence of said core element can be ascertained.