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US 12,521,810 B2Granted
Overvoltage protection for current braking switch
AssigneeEsab AB
InventorRolf Karlsson
Life of this patent
Estimating the term…
Abstract
A method includes supplying a welding current to a welding zone, monitoring, during a welding current ramp down period of a given short arc welding process cycle, a voltage across a current braking switch that is in an open state and that causes a decrease in welding current being supplied to a welding zone; and when the voltage across the current braking switch that is in the open state reaches a first predetermined voltage threshold, closing the current braking switch before a completion of the welding current ramp down period of the given short arc welding process cycle.
Claims17
A method comprising:
- supplying a welding current to a welding zone;
- monitoring, during a welding current ramp down period of a given short arc welding process cycle, a voltage across a current braking switch that is in an open state and that causes a decrease in the welding current being supplied to the welding zone;
- when the voltage across the current braking switch that is in the open state reaches a first predetermined voltage threshold, closing the current braking switch before a completion of the welding current ramp down period of the given short arc welding process cycle;
- and
- causing the current braking switch to again be in the open state before the completion of the welding current ramp down period of the given short arc welding process cycle,
- wherein the welding current ramp down period of the given short arc welding process cycle begins upon detecting a predetermined increase in arc voltage over time between an end portion of a welding wire and a workpiece and ends upon detecting a fuse of molten metal from the end portion of the welding wire, and
- wherein the welding current ramp down period of the given short arc welding process cycle is less than 0.3 ms.
4 more elements
A method comprising:
- supplying a welding current to a welding zone, the welding current being consistent with a short arc welding process;
- monitoring, during a welding current ramp down period of a given short arc welding process cycle, a voltage across a current braking switch that is used to decrease an amount of welding current being supplied to the welding zone;
- in response to the voltage across the current braking switch, turning off and on the current braking switch at least two times during the welding current ramp down period of the given short arc welding process cycle,
- wherein the welding current ramp down period of the given short arc welding process cycle begins upon detecting a predetermined increase in arc voltage over time between an end portion of a welding wire and a workpiece and ends upon detecting a fuse of molten metal from the end portion of the welding wire, and
- wherein a length of time for the welding current ramp down period of the given short arc welding process cycle is less than 0.3 ms.
2 more elements
Dependencies are inferred from the claim text.