GB292985A - Improvements relating to electric heating devices for welding, soldering and annealing - Google Patents

Abstract

292,985. Schr÷der, E. June 28, 1927, [Convention date]. Electrode and resistance furnaces. -A device for welding, soldering, and annealing, comprises a heating element having a cylindrical or conical heat radiating surface and arranged axially in a bell-shaped reflector constructed so that the radial rays are concentrated at a point. In Fig. 1 the heating element, comprises a tube subdivided by two or three slots parallel to its axis for connecting to a two or three-phase circuit. The tube may be made of tungsten or magnesia and supplied with low voltage current through a transformer. If magnesia is used preliminary heating of the tube is effected by a suitably arrarged heating coil. The reflector S may be made of sheet copper with shallow walls through which cooling water is passed. The reflecting surface is preferably silver plated. If tungsten is used the mouth of the reflector is covered by a plate of flint glass or potassium chloride filled with a protective gas. In Fig. 2, the heating element comprises a set of parallel, cylindrically arranged wires E', each enclosed in a shell E<2>. An inner cylinder S' having an external reflecting surface is provided. In a modification the heating body is a cylindrical carrier wound with a heating wire. The Specification as open to inspection under Sect. 91 (3) (a.) also describes an apparatus, Fig. 5 (Cancelled), wherein an arc is maintained between electrodes E' and caused to rotate by an electromagnet M. In Fig. 6 (Cancelled) arcs are struck between electrodes E<5> and are influenced by electromagnets M. The heat rays are concentrated by a lens G. This subject-matter does not appear in the Specification as accepted.