GB879675A - Improvements in or relating to seals substantially impervious to electromagnetic energy - Google Patents

Abstract

879,675. Electromagnetic-energy screening walls. BELLING & LEE Ltd. April 10, 1959, No. 12140/59. Class 20(4) In an electromagnetic-energy screening wall effective at radio frequencies, an electrical conducting sheet 1, Fig. 2, has a marginal portion overlying a strut 3, and a strip of electrical conducting material is bent to form one layer 7 on one side of the sheet 1, second and third layers 8, 9 on the other side of the sheet 1 and an extension strip 10 integral with the third layer 9 over the length thereof, either the second and third layers 8, 9, or the first layer 7 (Fig. 1, not shown) being sandwiched between the said marginal portion of the sheet 1 and batten 3. The extension strip may be bent to form similar layers 10, 11 and 12 associated with an adjacent electrical conducting sheet 2 coplanar with sheet 1 or at right angles thereto, Fig. 3 (not shown). Alternatively the extension strip 21, Fig. 4, may be applied to a face of the batten 18 carrying a sheet 1 which in construction of the wall is brought into contact with a corresponding face of a batten 19 carrying a sheet 2 which with the batten 19 is associated with a similarly bent strip having an extension strip 26 adapted to make electrical contact with the strip 21. A modified arrangement of Fig. 4 also serves for connecting sheets 1 and 2 at right angles one to the other. Capping strips 4, 20 and 23 are applied over the outer layer of the strips and are secured by screws passing through into the battens. The sheets and electrical conducting strips may be connected by blobs of solder. The electrical conducting strips are formed of expanded metal which may be initially bent into a T-formation, Fig. 6, or a Y-formation, which can be subsequently deformed to produce the disposition of layers in the various embodiments. The sheets 1 and 2 may be of expanded metal.