Patent ID: 6847008
Filing Date: 2005-01-25
Classification: B23K

Abstract:
1. An electric arc welding system for creating a first AC welding arc with a first current waveform between a first electrode and a workpiece by a first power supply and a second AC welding arc with a second current waveform between a second electrode and a workpiece by a second power supply as said first and second electrodes are moved in unison along a welding path, said first and second power supply each comprising an high speed switching inverter creating its waveform by a number of current pulses occurring at a frequency of at least 18 kHz with the magnitude of each current pulse controlled by a wave shaper and the polarity of said waveforms controlled by a signal, wherein at least said first AC waveform has a positive portion of substantially less energy than its negative portion and is phase shifted from said second AC waveform.