GB582549A - Improvements in welding apparatus - Google Patents

Abstract

582,549. Uniting by fusion. HEAD, WRIGHTSON, & CO.; Ltd., WRIGHTSON, SIR T. G., and WARRINER, R. H. May 16,1944, No. 9396. [Class 83 (iv)] A welding apparatus comprises a portable frame which movably supports a holder for a welding electrode and means for applying to the holder and its electrode a bias which is varied automatically as the electrode is consumed, whereby the distance of the electrode from the work is maintained substantially constant. The apparatus comprises a supporting plate 4 to which is secured an inverted L-frame 1 and a similar plate 6 to which are bolted side members 5 depending from a plate 3 connected to the other end of the L-frame by a lug 2. The lug 2 is bored to receive a rod 7 whose lower end bears in a block 9 having a clamping lever 13 and which may be rotated against the friction effect of a spring 11 by means of a rod 8. To enable the apparatus to be, supported, at various angles, the plates 4 and 6 have sides cut away at 45 degrees and extensions 37 with adjusting screws 38. An electromagnet 39 extending between the plates serves to hold the apparatus in position during welding. Upper and lower U-shaped levers 14, 15 connected together by a link 19 are pivotally mounted on two blocks secured to the rod 7. The lower lever 15 carries an arm 20 which supports a holder 21 for the electrode 22, whilst the upper lever carries two quadrants 27, 28 with which are associated levers 29, 30 having counterbalance weights 33, 35 adjustably clamped along the levers by screws 34, 36. In operation, the welding apparatus is placed in position and the lever 15, arm 20 and electrode holder 21 are balanced by means of the weight 33. The electrode is then inserted in the holder and the parts so balanced by means of the-weight 35 that the electrode is gently forced towards the work. The apparatus may be used for welding along a straight line horizontally either below or above the apparatus or along a straight line in a vertical direction, the arms 14 and 15 tilting as the electrode is consumed so that it is automatically kept in welding position. In a modified form of apparatus, the holder 221 of the electrode 220 is mounted on a block 45 slidable on a vertical rod 7 carried by a frame 100. Pivotally mounted on the block 45 is a rod 46 which passes between spaced pairs of rollers 47 in an open-ended frame 48 which is pivotally mounted on a part 50 of the frame and which carries the counterbalance weights 33, 35.