GB1045676A - Improvements in or relating to electrical bushings - Google Patents

Abstract

1,045,676. Bushing insulators. DUNLOP RUBBER CO. Ltd. Aug. 29, 1963 [Sept. 22, 1962], No. 36121/62. Heading H2C. An electrical bushing comprises a tubular flexible member 2 of insulating material having at least one layer of flexible conductive mesh 3 embedded therein. As shown, three spacedapart coaxial tubes 3 of aluminium wire mesh 4 are embedded in tube 2, the outermost wire mesh tube 3a being earthed at 6. The tube 2 may be manufactured from butyl rubber (see Specification), ethylene propylene rubber, natural rubber, or combinations of synthetic or natural rubber. The mesh 4 is orientated for maximum flexibility, as shown where part of the conductor 5 and tube 2 have been cut away. A layer of mesh may also be provided around the internal surface of the tubular member, and the outer layer may be of mesh instead of rubber as shown. The bushing may be manufactured by alternatively wrapping unvulcanized rubber sheet and aluminium mesh, into which a thin sheet of rubber has been pressed to exclude air, on a mandrel having a diameter equal to that of conductor 5, the whole then being cured. Alternatively extruded rubber tubes may be stretched over the mandrel, or narrow strips of sheet rubber and mesh may be wound helically upon the mandrel.