RESISTANCE WELDING APPARATUS

摘要

WELDING APPARATUS Resistance welding apparatus for simultaneously welding spaced generally parallel seams in sheet metal workpieces, as for example joining a pair of side panels to the back panel of a refrigerator cabinet. The panels are clamped upon a support table with their edges to be welded disposed in overlapping relationship. Support members of high electrical conductivity engage the underside of the clamped panels along and adjacent to the overlapped edge portions of the panels. A movable overhead carriage supports a pair of rotatable disc electrodes which axe positioned to roll along the overlapped edge portions of the panels in opposed relationship to the underlying support members Also mounted on the carriage are a pair of highly conductive shoes which roll along the central panel closely adjacent the respective electrodes. A highly conductive shaft electrically connects the shoes to each other to establish a confined low resistance electrical path for welding current which bridges the space in the central panel between the two seams to minimize current dissipation within the panel and the consequent power loss.