ROTARY ARC-WELDING APPARATUS

摘要

A nozzle (1) is rotated at high speed about its axis by a mechanism (5, 6) and has a passage (3, 10) for directing a consumable welding electrode (4) eccentrically from the center axis of the nozzle toward a groove formed between objects to be welded. A feed mechanism continuously directs the electrode toward the groove through the nozzle. Shielding gas is supplied to the arc welding zone by nozzles 28. A welding current supply arrangement comprises a current receiving plate (9) fixed to the top end of the rotatable nozzle, a stationary brush (11) having on the upper surface thereof a current feed plate (13), a plurality of rods (19) for holding the brush and the current feeding plate stationary, and a plurality of springs (22) for applying pressure onto the contact interface between the brush (11) and the rotating current receiving plate (9). The pressure is such that the nozzle (1) and the current receiving plate (9) can rotate while the brush (11) and the current feed plate (13) remain stationary and at the same time the welding current can flow smoothly from the brush (11) to the receiving plate (9). This arrangement avoids damage to the nozzle rotating mechanism (5, 6) by archeat or spatters and yet leads to only a small loss of welding current.