GB459132A - Method and apparatus for the manufacture of electrodes for arc welding or similar articles formed by coating a longitudinal core with plastic material - Google Patents

Abstract

459,132. Coating welding-electrodes &c. by extrusion machines. SARAZIN, R., 46, Boulevard d'Asnieres, Neuilly-sur- Seine, France. June 1, 1935, Nos. 15997 and 15998. Convention dates, June 2, 1934 and Jan. 10, 1935. [Class 87 (ii)] Coatings for electrodes for are welding and other articles comprising a coated wire or core are moulded by drawing the wire or electrode through an extrusion press and subjecting it to an additional tension by a braking or checking device 34 arranged at the inlet end of the extrusion press. The wire is also guided through the extrusion nozzle 45 by a central hole in a washer 44 positioned within the nozzle. A continuous wire formed from lengths welded together or a series of separate lengths may be coated and cut into appropriate lengths. The wire may be drawn from a drum 32 through a straightening device 33. The braking device 34 may comprise two bearings 35, 36 clamped together and made of vulcanized fibre, guaiacum wood, or other hard material. The extrusion press may comprise a piston inclined to the wire or arranged as at 38 to move upon a guide tube 37 within a cylinder 40. It may be operated hydraulically, pneumatically or mechanically. The coating paste 42 may be supplied from an auxiliary vat 46 by a handoperated piston 47. The nozzle 45 may be mounted on a large nut 43 closing the end of the cylinder and bored in ogival shape to provide passages for the paste. Lengths of wire may be drawn by a clamping jaw 49 moving on slides 50. For drawing a continuous length of wire, in one construction there is provided a wheel having transverse cutters on its periphery which grip the wire and a rotating saw is provided for finally cutting the coated wire into electrode lengths. In another construction, the wire is drawn by gripping jaws moving on an endless chain, the jaws being moved to grip or release the wire by rollers engaging a rail positioned alongside the wire. The jaws may also have cutters operated as by a boss on the rail. The cut electrodes may be removed on an endless belt to a drier. The coating may be removed from the wire at intervals corresponding to the length of an electrode as by a cutter rotating about the wire. For thick coatings two or more presses may be arranged in line. There may be a number of nozzles in one extrusion press. The Specification as open to inspection under Sect. 91 comprises also a construction of transverse cutter for the rotating drawing wheel, V-shaped cutters being fixed on the wheel periphery and the rod urged into the V-recesses by spring-loaded pivoted levers actuated by a cam surface. Further, constructions of coating apparatus are described wherein the wire is passed through a bath of fluid coating material and not through a press and also there is described a plant for drying the wire by hanging cut electrodes from an endless chain passing through a drying stove. The wires may be weighted and an electric current passed therethrough for drying. This subject-matter does not appear in the Specification as accepted.