GB1199562A - Improvements relating to Resistance Welding. - Google Patents

Abstract

1,199,562. Welding by pressure. PRESSED STEEL FISHER Ltd. 6 Sept., 1967 [8 June, 1966], No. 25524/66. Heading B3R. In resistance welding, one or more spherical pellets of weldable metal are interposed between the surfaces of the workpieces and pressure and current are applied to cause the pellets to fuse with the surfaces of the workpieces. In one embodiment three spheres 11 are held in a pattern by upper and lower tapes 12, 13 adhesively secured together at 14 and are arranged between workpieces 20, 21 in the electrodes of a resistance welder. The tapes are ruptured by the welding pressure and the workpieces may be welded together with a slight gap therebetween or in close contact. The pellets may be wholly embedded by extrusion in a flexible strip of expanded polystyrene or by allowing polystyrene to expand and mould to embrace the pellets. The pellets may alternatively stand proud of the strip. A flexible strip of expanded polystyrene in which pellets are embedded may have adhesively secured to both surfaces strips of paper, plastics tape or metal foil. Pellets may be secured to a thin strip of polystyrene, plastics tape or zinc foil by adhesive or to a thin sheet of polystyrene or metal foil by a layer of polyvinylchloride or polystyrene which embraces the pellets by a vacuum forming process. The layer may be of box form or may wrap around the pellets. The pellets may be welded directly to a metal foil to form an assembly. Three or more workpieces may be welded together by placing pellets only between the lower pair of workpieces or between each pair of surfaces to be welded, the pellets in the adjacent layers being in line or staggered.