| 摘要 |
PURPOSE:To make the spherical diameter at the top end of a wire as small as possible at the end of welding by regulating a welding feedback signal to a different signal at the end of welding, detecting the timing when the arc voltage after a min. holding voltage value transfers from short circuiting to an arc and interrupting the output power right after the generation of the arc. CONSTITUTION:When an arc start signal Sw turns off at the end of welding, a motor brake signal SB turns on and switch elements 14, 17 are opened, and 15 is closed. A reference signal ES is entered as the signal (es) from a voltage generating circuit 13 for detecting short circuiting and a feedback signal Ef is entered as the signal regulated to enable the detection of a short circuiting arc in a capacitor C2, respectively into a control circuit 16. The control circuit 16 outputs a control signal Cs for increasing or decreasing the predetermined step output voltage to an output voltage regulating circuit and detects the short circuiting timing after the min. holding voltage Em and interrupts the output voltage right after the time (point PS) when the short circuiting transfers to the arc. The ball at the top end of the wire at the end of welding is thus made small and the next arc starting is stabilized. |
