GB870218A - Improvements in or relating to electric resistance welding apparatus - Google Patents

Abstract

870,218. Welding by pressure. KELLER & KNAPPICH MASCHINENFABRIK G.m.b.H. May 5, 1959 [Nov. 19, 1958], No. 15309/59. Class 83 (4). In an electric resistance-welding machine for circular seam welding in which an electrode head is urged against the surfaces to be welded and is rolled around the path of the weld, the electrode head has an annular end surface of the same diameter as that of the weld path and is adapted to be forcibly rotated about an axis oblique to the plane of the surfaces to be welded and a holder for a carrier for the electrode head and defining the axis of rotation of the electrode head is freely rotatable about an axis substantially coincident with the axis of the weld path. The truncated conical electrode 1 with its annular surface 2 has a Morse taper mounting in a shaft 6 keyed to and adjustable in a sleeve 7. Cooling water ducts 4 are provided in the electrode and one or two terminals 5 are connected to the electrode. The sleeve 7 is rotatable in bearings 12, 13 in the holder 14 connected to a sleeve 15 rotatable in bearings 16, 17 in a hollow shaft 18. The shaft 18 carries a piston 19 in a cylinder space 21 formed in a housing 23 and pressure may be applied to the piston to exert welding-pressure against the force of tensionsprings 22. A drive-shaft 25 is mounted within the sleeve 15 in a bearing 24, the lower end carrying the bevel gear 29 meshing with a bevel gear 30 carried on the sleeve 7 and the upper end keyed to a driven bevel-gear 27 mounted in the housing 23. The axis A of shaft 25 passes through the centre of the flanges d, e,. to be welded as does the axis B of the electrode. When the bevel gears are rotated and the piston is acted on by pressure the axis B describes a conical path about axis A and the surface 2 rolls around the flanges while counter-pressure is applied by lower electrode 31.