Patent ID: 8530778

Claim:
An apparatus for controlling blanket gas flow in an electrical welding facility, wherein welding is performed using a welding electrode in electrical connection with a welding machine unit, the apparatus comprising: (a) an electric measuring device having (a1) a current sensor adapted to determine the magnitude of an electrical welding current carried in a circuit incorporating the welding electrode and having a current sensor output adapted to provide a I signal indicating the current magnitude, and (a2) a voltage sensor adapted to determine the magnitude of an electrical voltage being applied to the welding electrode and having a voltage sensor output for providing a U signal indicating the voltage magnitude; and (b) a control device having (b1) inputs connected to the current sensor output and the voltage sensor output, respectively, and a control signal output for providing a control signal to a blanket gas flow controller, and (b2) a controller adapted to provide the control signal as (i) a control signal of a predetermined first magnitude when the U signal is larger than the first U threshold and the I signal is less than a first I threshold, and (ii) a control signal of a magnitude varying proportionally with the I signal when the I signal is greater than the first I threshold.