Magnetically and radio frequency shielded enclosure

• US 4,959,504 A
• Filed: 11/22/1988
• Issued: 09/25/1990
• Est. Priority Date: 11/22/1988
• Status: Expired due to Fees

• Current Assignee: Magneshield Technologies Incorporated
• Original Assignee: Magneshield Technologies Incorporated
• Inventors: Yarger, Eric J., Clegg, Gary D., Yarger, Rex D.
• Primary Examiner(s): Picard, Leo P.
• Assistant Examiner(s): Tone, David A.
• Application Number:
  US07/274,864
• Time in Patent Office: 672 Days
• Field of Search: 174/35 MS
• US Class Current: 174/386
• CPC Class Codes: H05K 9/0001 Rooms or chambers anechoic chambers G01R29/0821

Abstract

A self-contained room capable of shielding the interior environment from magnetic and radio frequency interferences, as well as other wave and vibrational disturbances, comprised of an outer enclosure and an inner enclosure, raised above an existing floor by a fiberglass dowel system. The walls of both enclosures are made of mumetel sheets, pressure sealed to protect against ambient and man-made interferences, with an underlying aluminum structural frame. All seams and penetrations are shielded against wave interferences of natural or man-made origin.

Claims

1. A magnetic and radio frequency-shielded room comprising, in combination:

an aluminum sheet placed upon the existing floor of the building in which the room is to be placed;

an outer enclosure comprised of four walls, a ceiling, and a floor, each side of said enclosure being constructed of mumetal sheets abutted together, the seam formed by said abutting of said sheets being pressure sealed by application of a mumetal strip overlayed by an aluminum flat bar strip, both strips then being attached to said mumetal sheets by screw means screwed through mumetal sheets to underlying structural members;

a plurality of pneumatic isolators attached to the bottom of said outer enclosure raising said enclosure above said aluminum sheet;

an inner enclosure disposed within, and of less dimensions than, said outer enclosure, comprised of four walls, a ceiling, and a floor, each side of said enclosure being constructed of mumetal sheets abutted together, the seam formed by said abutting of said sheets being pressure sealed by application of mumetal strip overlayed by an aluminum flat bar strip, both strips then being attached to said mumetal sheets by screw means screwed through mumetal sheets to the underlying structural members;

a sheet of underlying structural material underlying said connected and sealed mumetal sheets of said outer enclosure and said connected and sealed mumetal sheets of said inner enclosure, said sheet of underlying structural material being screwed to said mumetal sheets;

an inner work floor comprised of layers of plywood overlayed by self adhesive tiling material;

a plurality of fiberglass dowels, the lower end of each being permanently affixed within an aluminum pipe stub permanently welded to said aluminum sheet, and the upper end of each said dowel being affixed within an aluminum pipe stub sunk into the bottom layer of said plywood of said inner floor, each dowel passing through said floor of said outer enclosure and said floor of said inner enclosure through holes drilled in said floor of said outer enclosure and through holes drilled in said floor of said inner enclosure, and through aluminum flat bar attached to and extending the length of the bottom surface of said inner floor, said holes being provided with magnetic wave guides and RF wave guides;

a crossed network of wooden beams disposed upon the upper surface of said floor of said outer enclosure separating said outer enclosure from said inner enclosure;

"I" beams welded to the upper surface of the ceiling of said inner enclosure;

a cable feed-through system comprised of a hooded plate disposed on said outer wall of said outer enclosure with honeycomb or rectangular cable feed through openings;

an enclosure vent system comprised of mumetal tube perforated mumetal plate, aluminum collar, and plastic flex hose connecting two vent subassemblies.

2. A shielded room as set forth in claim 1 in which said mumetal sheets are constructed of any type of metal with a permeability rating equaling or exceeding 100.

3. A shielded room as set forth in claim 1 in which said mumetal sheets of said outer enclosure and said inner enclosure are joined in a squared fashion.

4. A shielded room as set forth in claim 1 in which said mumetal sheets of said outer enclosure and said inner enclosure are staggered.

5. A shielded room as set forth in claim 1 in which the walls, ceiling and floor of said outer enclosure are joined by application of mumetal angle upon the joint, overlayed by aluminum angle, and a pressure seal applied followed by attachment of all layers by screw means, and the walls, ceiling and floor of said inner enclosure are joined by application of mumetal angle upon the joint, overlayed by aluminum angle, and a pressure seal applied followed by attachment of all layers by screw means.

6. A shielded room as set forth in claim 1 in which the outer corners of the inner mumetal layer and the outer corners of the outer mumetal layer have staggered joints, with cornerpieces welded prior to the annealing process applied to said mumetal sheets and said angle, said mumetal sheets and angles may be affixed in place using screws, rivets, adhesives, or bolts.

7. A shielded room as set forth in claim 1 in which said conductive sheet underlying said mumetal sheets is made of aluminum.

8. A shielded room as set forth in claim 1 in which said conductive sheet underlying said mumetal sheets is made of copper.

9. A shielded room as set forth in claim 1 in which said work floor is isolated from said floor of said inner enclosure by use of an insulating material.

10. A shielded room as set forth in claim 1 in which said mumetal sheets are comprised of multiple laminated layers of metal bonded together by a bonding agent, said laminated layers being placed one upon the other with edges flush.

11. A shielded room as set forth in claim 1 in which said mumetal sheets are comprised of multiple laminated layers of metal bonded together by a bonding agent, each said laminated layer being offset from the layer above or below, and said mumetal sheets thus configured being joined.

12. A magnetic and radio frequency-shielded room comprising, in combination:

an aluminum sheet placed upon the existing floor of the building in which the room is to be placed;

an outer enclosure comprised of four walls, a ceiling, and a floor, each side of said enclosure being constructed of mumetal mesh attached to an aluminum frame;

a plurality of pneumatic isolators attached to the bottom of said outer enclosure raising said enclosure above said aluminum sheet;

an inner enclosure disposed within, and of less dimensions than, said outer enclosure, comprised of four walls, a ceiling, and a floor, each side of said enclosure being constructed of mumetal mesh attached to an aluminum frame;

an inner floor comprised of layers of plywood overlayed by self adhesive tiling material;

a plurality of fiberglass dowels, the lower end of each being permanently affixed within an aluminum pipe stub permanently welded to said aluminum base, and the upper end of each said dowel being affixed within an aluminum pipe stub sunk into the bottom layer of said plywood of said work floor, each dowel passing through said floor of said outer enclosure and said floor of said inner enclosure through holes drilled in said floor of said outer enclosure and through holes drilled in said floor of said inner enclosure, and through an aluminum flat bar attached to and extending the length of the bottom surface of said work floor, said holes being provided with magnetic wave guides and RF wave guides; and

a crossed network of wooden beams disposed upon the upper surface of said floor of said outer enclosure separating said outer enclosure from said inner enclosure.