Patent ID: 7109439
Filing Date: 2006-09-19
Classification: B23K

Abstract:
1. In an electric arc welder operated to perform a short circuit welding process between an electrode and a workpiece, said process comprising a succession of alternate short circuit conditions and arc conditions, with a first waveform during said short circuit condition and a second waveform during said arc condition, a first waveform generator to construct said first waveform from a series of current pulses controlled by a pulse wave modulator operated at a rate greater than 18 kHz and a second waveform generator to construct said second waveform from a series of current pulses controlled by a pulse wave modulator operated at a rate greater than 18 kHz, the improvement comprising: said first waveform generator having a circuit to generate said first waveform as a current control signal and said second waveform generator having a circuit to generate said second waveform, with a generally constant arc parameter, as one of a constant voltage signal or a constant wattage signal, wherein said first waveform generator and said second waveform generator are configured to operate in a generally sequential fashion with respect to each other.