| 摘要 |
PURPOSE:To prevent the generation of welding expulsion and surface flash by using plural pieces of condensers which permit respectively desired setting of charging voltages and discharge starting time thereby generating an optional welding current waveform to deal with various works. CONSTITUTION:Control circuits 7-10 for charging voltages of condensers set the respective charging voltages of condensers 2-5 in such a way that the current pulse waveforms of gradually increasing peak values IP1-IP4 are generated successively on the secondary side of a welding voltage transformer 11 when the condensers are respectively independently discharged. A timing circuit 16 is so set that the discharge of the condensers 2-5 is started at successively increasing time T0-T3. If the welding is started after all the condensers are fully charged, the welding current of the waveform shown in the figure is obtd. Required welding energy is thus obtd. even with the relatively low peak current value and the generation of welding expulsion and surface flash is inevitably prevented. |
