METHOD OF EXCITATION OF AC WELDING ARC AND DEVICE FOR ITS ACCOMPLISHMENT Russian patent published in 1996 - IPC

FIELD: electric arc welding of metals by fusible electrode; intended for welding of steel and non-ferrous metal constructions of small thicknesses. SUBSTANCE: the method of excitation of AC welding arc consists in preliminary ionization of the arc gap by a high-voltage exciting pulse. The high-voltage exciting pulse is fed at a frequency equal to the alternating current frequency of the power source simultaneously with the beginning of feeding of current to the power source, the polarity being the same as the polarity of the no-load voltage of the power source. The device for excitation of AC welding arc uses a power source, accumulating element, thyristor switch, high-voltage transformer, pulse transformer, trigger pulse shaper. The device also has a rectifier, current regulator and a choke; the beginning and end of the primary and secondary windings of the transformers and choke are connected in such a way so as to ensure coincidence of polarities of the high-voltage pulse and no-load voltage. EFFECT: facilitated procedure. 3 cl, 3 dwg