APPARATUS FOR ELECTRIC ARC WELDING Russian patent published in 2003 - IPC

FIELD: electrical engineering, namely apparatuses for electric arc welding and method for making magnetic circuits, possibly in welding apparatuses with generation of alternating current with drop Volt-Ampere characteristic. SUBSTANCE: first portion of closed magnetic circuit has cross section providing its saturation at idle stroke; it supports secondary winding of transformer electrically connected with terminal of electrode and with ground terminal. Second portion of said magnetic circuit has cross section providing non-saturation at all working modes and it supports primary winding electrically connected through throttle with network for generating AC voltage. Throttle has magnetic circuit and in first portion it has main winding connected in series with primary winding of transformer and embracing second portion of magnetic circuit of transformer. Primary winding of transformer embraces first portion of magnetic circuit of throttle. In second variant of invention primary windings of transformer and throttle form common winding arranged in first portion of magnetic circuit of transformer. On second portion of magnetic circuit of transformer having cross section providing its saturation at idle stroke secondary winding is arranged. In third portion additional winding of throttle is arranged with possibility of series connection with common winding. In third variant of invention apparatus includes magnetic switches, induction filter, bias induction turn, driving pulse shaper and terminals for connection with used welding transformer. In order to provide magnetic circuit with variable cross section, preliminarily measure-cut pieces of steel sheets are periodically applied at winding on zones of increased cross section between adjacent turns of wound band. EFFECT: lowered mass, enhanced technical and economical parameters of apparatus. 4 cl, 13 dwg