GB1368308A - Koi ssr machine for resistance butt welding of rods to sheets - Google Patents

Abstract

1368308 Welding by pressure INSTITUT ELEKTROSVARKI IMENI EO PATONA AKADEMII NAUK UKRAINSKOI SSR 28 Dec 1971 60227/71 Heading B3R A machine for resistance butt welding rods to a sheet comprises a welding head 2 on a frame 3, the head including upper electrodes 11 having jaws to grip the rods and lower electrodes 7 which engage the sheet, welding transformers 4 to which the electrodes are connected, a vertically movable beam 10 on which the upper electrodes are mounted and having apertures 27 coaxial with the jaws of the upper electrodes, means 13 for clamping a sheet upon the electrodes 7 and mechanisms for supplying rods to a welding position, one for each electrode 11, each comprising a rotatable apertured plate 15 mounted on the beam, the apertures 18 in the plate being in a circle and each adapted to accommodate a rod, a cover-plate 19 fixed below the plate 15 and having a single aperture 26 coaxial with the jaws of the upper electrode, drive means 16 for rotating the apertured plate 15 stepwise so that each aperture 18 passes in turn the aperture 26 in the cover-plate and a shutter 17 below the beam to provide a support for the upper end of a rod during welding. The welding head 2 comprises a fixed lower beam 5, carrying electrodes 7, and the upper beam 10 which is carried on the rod of a piston and cylinder device 6. The beam 10 carries electrodes 11 and spring pin devices 13 for clamping a sheet upon the electrodes 7 and the mechanisms for feeding rods to the electrodes 11. The head 2 is mounted on rollers for movement with fed sheets along the frame of the machine, being returned by a ram. The plate 19 beneath the plate 15 closes all the passages except one and a ram 20 operated ratchet device 22 rotates the plate 15 step by step. A passage 27 in the beam 10 is aligned with the hole 26 in the plate 19 and the shutter 17 is operated by the ram ratchet device. In operation with the passages 18 in each plate 15 accommodating rods to be welded to a fed sheet 34, with one rod in the hole 27 and held by the shutter 17, the beam 10 is lowered, the ratchet ram 20 retracts its rod 23 to move the shutter 17 and allow the rod to be received by electrode 11. As the beam continues to descend the sheet 34 is clamped by the means 13 and a signal from a timer causes ram 20 to operate to move the shutter 17 to its closing position and to rotate the plate 15 through one step, the next rod then falling on to the shutter 17. The electrodes 11 clamp the rods and when the rods engage the sheet, being pressed by the shutters 17, current is supplied to effect welding. After returning the beam 10 to its upper position the head is returned by its ram. Welding may be effected on a stationary sheet.