SINGLE-PHASE RECTIFIER FOR ARC WELDING Russian patent published in 2012 - IPC B23K9/95 

FIELD: welding.

SUBSTANCE: invention refers to single-phase rectifier for arc welding. The rectifier includes transformer (1) with primary coil (2) connected to the supply network and three half-coils. Power coil (3) is loaded to the diode thyristor bridge rectifier. One additional coil (5) is connected to the arc stabilization unit and the other one (4) is connected to the control unit (10). Between common connection points of pick-off diodes with thyristor (11, 12) condenser (20) is installed. The diagonal of direct current formed by thyristor and diodes includes impedance coil (13) and current sensor (14) the output of which is connected to the protection unit (23). Parallel to the load resistor (22) is connected through the closed relay contact (21). The arc impulse stabilization unit (6) includes rectifier (7) with condenser (8) and discharge thyristor (9) connected to the impedance coil (13). Protection unit (23) is made of two threshold elements. Each of them consists of setting potentiometer and stabilitron (27) at the input of transistor (29). Collector of one transistor is connected to relay (31) and collector of another is connected to optical diode (33) the phototransistor of which serves as a shunt for potentiometer of driving voltage. Its driver is connected to the transistor of variable resistance shunting resistor of integrating RC-circuit connected to the input of pulse-length modulator of control unit.

EFFECT: high energetic values, reliability and short-circuit current and off-load voltage limitation.

3 cl, 4 dwg