High current AC welder

• US 20070215585A1
• Filed: 03/15/2006
• Published: 09/20/2007
• Est. Priority Date: 03/15/2006
• Status: Abandoned Application

• Current Assignee: Lincoln Global Incorporated (Lincoln Electric Holdings Incorporated)
• Original Assignee: Lincoln Global Incorporated (Lincoln Electric Holdings Incorporated)
• Inventors: O'Connor, James
• Application Number:
  US11/375,767
• Publication Number:
  US 20070215585A1
• Time in Patent Office: Days
• US Class Current: 219/130.100
• CPC Class Codes: B23K 9/1043 characterised by the electric circuit B23K9/1012 takes precedence
• CPC Class Codes: B23K 9/1081 Arc welding by means of accumulated energy

Abstract

An electric arc welding assembly comprising a charging circuit and regulator coupled to an input power source, an energy storage element connected in parallel with the charging circuit and regulator to increase the power available for the weld output, and a weld output controller connected in parallel with the energy storage element for controlling a welding arc between an electrode and a workpiece.

Claims

1. An electric arc welding assembly comprising:

a. a charging circuit and regulator coupled to an input power source;

b. an energy storage element connected in parallel with the charging circuit and regulator to increase the weld current output, wherein the energy storage element is charged by the charging circuit and regulator; and

c. a weld output controller connected in parallel with the energy storage element for controlling a welding arc between an electrode and a workpiece.

2. The electric arc welding assembly defined in claim 1, wherein the energy storage element comprises at least one battery.

3. The electric arc welding assembly defined in claim 1, wherein the energy storage element comprises at least one capacitor.

4. The electric arc welding assembly defined in claim 1, wherein the energy storage element comprises at least one battery and at least one capacitor connected in parallel.

5. The electric arc welding assembly defined in claim 1, wherein the weld output controller comprises a DC down chopper including a pulse width modulator that at least partially controls the welding current to the electrode and a waveform generator that at least partially controls the pulse width modulator, the DC down chopper creating a series of current pulses that constitute a welding cycle representative of a current waveform, the pulse width modulator controlling a current pulse width of a plurality of the current pulses.

6. The electric arc welding assembly defined in claim 5, wherein the waveform generator drives the pulse width modulator at a frequency of 20 kHz.

7. The electric arc welding assembly defined in claim 1, wherein the weld output controller comprises a forward converter/inverter including a series circuit of a primary winding of a transformer and a switching element, which is coupled to the energy storage element and a rectifier smoothing circuit which rectifies and smoothes a voltage induced in a secondary winding of the transformer according to a switching operation of the switching element, wherein a rectifier element of the rectifier smoothing circuit conducts during an ON period of the switching element.

8. The electric arc welding assembly defined in claim 1, wherein the weld output controller comprises a boost converter.

9. The electric arc welding assembly defined in claim 1, wherein the weld output controller comprises at least one of a DC down chopper, a forward converter/inverter, and a boost converter.

10. The electric arc welding assembly defined in claim 1, wherein the weld output controller comprises a DC down chopper and a boost converter connected in parallel.

11. The electric arc welding assembly defined in claim 1, wherein the input power source comprises a 110-120 volt AC wall outlet.

12. The electric arc welding assembly defined in claim 11, further comprising an input cord and three-prong plug for connecting to the 110-120 volt AC wall outlet.

13. The electric arc welding assembly defined in claim 1, further comprising an input cord and three-prong plug for connecting to the 220-240 volt AC wall outlet.

14. The electric arc welding assembly defined in claim 13, further comprising an input cord and three-prong plug for connecting to the 220-240 AC wall outlet.

15. A method of forming an electric arc between an electrode and a workpiece comprising:

a. providing an electric arc welding assembly having a charging circuit and regulator coupled to an input power source, an energy storage element connected in parallel with the charging circuit and regulator, and a weld output controller connected in parallel with the energy storage element;

b. charging the energy storage element with the charging circuit and regulator;

c. increasing the weld current output via the stored energy in the energy storage element; and

d. controlling a welding arc between an electrode and a workpiece via the weld output controller.

16. The method defined in claim 15, wherein the energy storage element comprises at least one battery.

17. The method defined in claim 15, wherein the energy storage element comprises at least one capacitor.

18. The method defined in claim 15, wherein the energy storage element comprises at least one battery and at least one capacitor connected in parallel.

19. The method defined in claim 15, wherein the weld output controller comprises a DC down chopper including a pulse width modulator that at least partially controls the welding current to the electrode and a waveform generator that at least partially controls the pulse width modulator, the DC down chopper creating a series of current pulses that constitute a welding cycle representative of a current waveform, the pulse width modulator controlling a current pulse width of a plurality of the current pulses.

20. The method defined in claim 19, further comprising driving the pulse width modulator with the waveform generator at a frequency of 20 kHz.

21. The method defined in claim 15, wherein the weld output controller comprises a forward converter/inverter including a series circuit of a primary winding of a transformer and a switching element, which is coupled to the energy storage element and a rectifier smoothing circuit which rectifies and smoothes a voltage induced in a secondary winding of the transformer according to a switching operation of the switching element, wherein a rectifier element of the rectifier smoothing circuit conducts during an ON period of the switching element.

22. The method defined in claim 15, wherein the weld output controller comprises a boost converter.

23. The method defined in claim 15, wherein the weld output controller comprises at least one of a DC down chopper, a forward converter/inverter, and a boost converter.

24. The method defined in claim 15, wherein the weld output controller comprises a DC down chopper and a boost converter connected in parallel.

25. The method defined in claim 15, wherein the input power source comprises a 110-120 volt AC wall outlet.

26. The method defined in claim 25, further comprising an input cord and three-prong plug for connecting to the 110-120 volt AC wall outlet.

27. The method defined in claim 15, further comprising an input cord and three-prong plug for connecting to the 220-240 volt AC wall outlet.

28. The method defined in claim 27, further comprising an input cord and three-prong plug for connecting to the 220-240 AC wall outlet.