US 12,403,543 B2
Systems and methods to start arc welding
Robert R. Davidson, New London, WI (US); Peter Mehn, Oshkosh, WI (US); and John Smith, Glendale Heights, IL (US)
Assigned to Illinois Tool Works Inc., Glenview, IL (US)
Filed by Illinois Tool Works Inc., Glenview, IL (US)
Filed on Oct. 26, 2018, as Appl. No. 16/171,727.
Prior Publication US 2020/0130094 A1, Apr. 30, 2020
Int. Cl. B23K 9/12 (2006.01); B23K 9/067 (2006.01); B23K 9/073 (2006.01); B23K 9/095 (2006.01); B23K 9/10 (2006.01)
CPC B23K 9/125 (2013.01) [B23K 9/0672 (2013.01); B23K 9/0737 (2013.01); B23K 9/0956 (2013.01); B23K 9/1062 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A welding-type power supply, comprising:
power conversion circuitry configured to convert input power to welding-type power, and configured to output the welding-type power to output terminals;
a touch detection circuit coupled to the output terminals, in parallel with the power conversion circuitry, and configured to output a touch detection signal via the output terminals; and
control circuitry configured to:
prior to a welding operation, disable output of the welding-type power to the output terminals by the power conversion circuitry;
monitor the output terminals based on the touch detection signal to identify a contact between a wire electrode and a workpiece coupled to the output terminals; and
in response to identifying the contact between the wire electrode and the workpiece:
control the power conversion circuitry to output an arc starting current to the output terminals to initiate an arc;
while the arc starting current is being output to the output terminals, control a feed motor of a welding torch to retract the wire electrode;
control the feed motor to advance the wire electrode based on a first parameter of the welding operation;
control the power conversion circuitry to output the welding-type power to the output terminals based on the first parameter or a second parameter of the welding operation;
monitor for a threshold voltage; and
when the threshold voltage is reached, (1) change to a transition mode and start a timer or (2) switch to a ramp-in mode.