| 摘要 |
PURPOSE:To ensure regeneration of an arc by detecting occurrence of short- circuit using a short-circuit detecting circuit, and in case of occurrence of short- circuit, eliminating the short-circuit by supplying large current corresponding to pulse current with priority to and regardless of set pulse frequency and time width. CONSTITUTION:When an arc is generated normally without causing short-circuit between an electrode 1 and an object 2 or 3 to be welded during welding, pulse current value of pulse peak value and pulse time width determined by a signal synthesized by a signal synthesizing circuit 13 is supplied at a specified period overlapping with the output of DC power source 8 for base current. In case of occurrence of short-circuit, output of a short-circuit detecting circuit 9 is supplied to a gate circuit 14 and output of the circuit 13 is cut off. At the same time, an output signal of a pulse peak current setting device 10 is supplied directly to a driving circuit 6 and an output current controlling element 5 is made to conduct to output large current corresponding to pulse peak current continuously. By this way, it is possible to regenerate the arc easily by melting and scattering the tip of the electrode 1 by rapid heating. |
