Stick welder
AssigneeIllinois Tool Works Inc.
InventorsEdward Beistle, Todd Batzler
Life of this patent
Estimating the term…
Abstract
A system and method for forming an arc between an electrode and a workpiece is disclosed. The present invention includes a method of initiating an arc that includes comparing voltage across output terminals of a stick welder to a voltage threshold, and if the voltage across the output terminals is less than the voltage threshold, increasing the voltage across the output terminals to an arc formation OCV. The output voltage of the stick welder will be driven to a lower OCV if an arc is not formed between an electrode and a workpiece within a given period of time.
Claims20
A method of initiating an arc comprising the steps of:
- comparing voltage across output terminals of a stick welder to a voltage threshold;
- if the voltage across the output terminals is less than the voltage threshold, increasing the voltage across the output terminals from an OCV to an arc formation voltage that exceeds the OCV to create an arc between an electrode and a workpiece;
- determining if an arc has been created between the electrode and the workpiece within a given time period;
- and if not,
- adjusting the voltage across the output terminals to the OCV.
A welding apparatus comprising:
- a stick welder;
- an electrode operationally connected to the stick welder;
- and
- a controller disposed in the stick welder and configured to:
- set the stick welder to a pre-welding state upon powering-up of the stick welder, the stick welder configured to provide an OCV when in the pre-welding state;
- detect a short between the electrode and a workpiece;
- upon detection of a short between the electrode and the workpiece, set the stick welder to an arc formation state, the stick welder configured to deliver an arc formation voltage that exceeds the OCV when in the arc formation state;
- monitor voltage output of the stick welder for a defined period of time;
- and
- if an arc is not created between the electrode and the workpiece before expiration of the defined period of time then return the stick welder to the pre-welding state and cause the stick welder to provide the OCV at a level substantially less than arc formation voltage.
A controller configured to:
- detect a short circuit between an electrode of a stick welder and a workpiece;
- if a short is detected, increase voltage output of the stick welder from an OCV to a boosted voltage;
- initiate a countdown timer when a short is detected;
- and
- if an arc is not formed between the electrode and the workpiece before expiration of the countdown timer then decrease voltage output of the stick welder to the OCV.
Dependencies are inferred from the claim text.