POWER SUPPLY SOURCE FOR ARC WELDING, DEVICE FOR ARC EXCITATION AND CURRENT OVERLOAD PROTECTION DEVICE Russian patent published in 1996 - IPC

FIELD: welding. SUBSTANCE: power supply source includes power part, control unit, current overload protection device and device for arc excitation. Control unit makes it possible to adjust current, voltage, inclination of volt-ampere characteristic. Current overload protection device has current pickup, two sources of reference voltage, amplifier, two comparators, adder and sawtooth voltage generator. This device ensures fast-action current overload protection unsusceptible to self-excitation. Device for arc excitation includes short-circuit pickup, idle-run voltage pickup, delay unit, unit to count pulse duration, flip-flop and logic AND gate. This device enable arc to be easily excited by touching of article with electrode not causing sticking of electrode to article, prevents danger of hitting of welder with voltage of idle run and makes it possible to conduct welding by single pulses with accurate dosage of energy and duration of pulse. EFFECT: improved operational efficiency and safety. 3 cl, 4 dwg