Pressure stabilized radio frequency gasket

• US 5,214,241 A
• Filed: 09/20/1991
• Issued: 05/25/1993
• Est. Priority Date: 09/20/1991
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Secretary Of The Army (Government of the United States of America)
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Benwell, Bruce T.
• Primary Examiner(s): Picard, Leo P.
• Assistant Examiner(s): Ledynh, Bot L.
• Application Number:
  US07/762,992
• Time in Patent Office: 613 Days
• Field of Search: 220/217, 220/225, 220/228, 220/239, 277/34, 277/34.3, 277/34.6, 174/35 R, 174/35 MS, 174/35 GC
• US Class Current: 174/364
• CPC Class Codes: H05K 9/0015 Gaskets or seals
• CPC Class Codes: Y10S 277/919 Seal including electrical feature
• CPC Class Codes: Y10S 277/92 Seal including electromagnetic shielding feature
• CPC Class Codes: Y10S 277/921 Closure or weather strip seal

Abstract

A radio frequency gasket assembly having a flexible hollow tube enveloped a conductive layer, and filled with a compressible fluid, or a combination of both compressible and incompressible fluids. In one embodiment thereof, the undeformed gasket is filled completely with a compressible fluid, such as air. When the gasket is compressed, a portion of the fluid is allowed to collect in a spring-loaded reservoir, maintaining at all times a substantially constant internal pressure. When the compressive force is removed, the collected fluid re-enters the gasket, which may then assume its original undeformed profile. In another embodiment thereof, the undeformed gasket is filled with a mixture of both compressible and incompressible fluids. When the gasket is compressed, a portion of the compressible fluid is evacuated or collected in a spring-loaded reservoir or the like, maintaining at all times a substantially constant internal pressure. When the compressive force is removed, an equal amount of compressible fluid is re-introduced into the gasket, which may then assume its original undeformed profile.

Claims

1. An apparatus for providing an electrically conductive seal between two surfaces, said apparatus comprising:

a gasket comprising a flexible hollow tube, a mixture of air and an incompressible fluid contained within said hollow tube, and mans for covering said hollow tube, wherein said covering means envelops said tube and is electrically conductive;

mans for releasing a portion of said air upon compression of said hollow tube;

means for introducing an equal portion of air back into said hollow tube when said hollow tube is no longer under compression, whereby said hollow tube will resume its original undeformed profile, and a substantially constant internal pressure will be maintained at all times within said hollow tube.

3. The invention of claim 1 or 2 wherein said gasket is attached to a shielded door of a shielded enclosure, and said means for releasing a portion of said air from, and introducing an equal portion of air back into said gasket is comprised of:

a spring-loaded reservoir attached to said door;

a hollow tube disposed between said gasket and spring loaded reservoir.

4. The invention of claim 1 or 2 wherein said gasket is attached to a shielded door of a shielded enclosure, and said means for releasing a portion of said air from, and introducing an equal portion of air back into said gasket is comprised of:

a mechanical air pump which is attached to said door, wherein said air pump has a plunger which is in contact with said shielded enclosure;

a hollow tube disposed between said gasket and air pump;

a release valve disposed between said gasket and air pump.

5. The invention of claim 1 or 2 wherein said gasket is attached to a shielded door of a shielded enclosure, and said means for releasing a portion of said air from, and introducing an equal portion of air back into said gasket is comprised of:

a mechanical air pump which is attached to said door, wherein said air pump has a plunger which is attached to and operated by the latching means of said door;

a hollow tube disposed between said gasket and air pump;

a release valve disposed between said gasket and air pump.

6. The invention of claim 1 or 2 wherein said gasket is attached to a shielded door of a shielded enclosure, and said means for releasing a portion of said air from, and introducing an equal portion of air back into said gasket is comprised of:

a regulated air supply provided with a power supply and release valve;

a hollow tube disposed between said gasket and regulated air supply.

2. An apparatus for providing an electrically conductive seal between two surfaces, said apparatus comprising:

a gasket comprising a flexible hollow tube filled with air and means for covering said hollow tube, wherein said covering means envelops said tube and is electrically conductive;

means for releasing a portion of said air upon compression of said hollow tube;

means for introducing an equal portion of air back into said hollow tube when said hollow tube is no longer under compression, whereby said hollow tube will resume its original undeformed profile, and a substantially constant internal pressure will be maintained at all times within said hollow tube.