Circuit for use with arc voltage controllers in AC gas tungsten arc welding

摘要

A signal conditioning circuit for providing a DC voltage to an arc voltage controller for controlling the length of an AC arc of a gas tungsten arc welder. Specifically, a first control circuit is employed which charges to a first value by a signal of a given polarity of one cycle of the AC arc for providing a DC voltage and an additional control circuit is employed for rapidly discharging the first control circuit when the maximum absolute amplitude of a signal of a given polarity of a subsequent cycle of the AC arc is less than the DC voltage provided by the first control circuit. The first control circuit is charged to a higher second value when the maximum absolute amplitude of a signal of a given polarity of a subsequent cycle of the AC arc is greater than the DC voltage provided by the first control circuit. In a preferred embodiment, a doubling circuit is employed to provide a DC voltage roughly equivalent to twice the DC voltage provided by the first control circuit and bias circuitry is employed for providing power to the additional control circuit.