Method and apparatus for welding

• US 6,777,649 B2
• Filed: 05/21/2002
• Issued: 08/17/2004
• Est. Priority Date: 05/21/2002
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Reynolds, Jon O., Matus, Timothy
• Primary Examiner(s): Shaw, Clifford C.
• Application Number:
  US10/152,711
• Publication Number:
  US 20030217998A1
• Time in Patent Office: 819 Days
• Field of Search: 219/130.1, 219/130.21, 219/130.31, 219/130.32, 219/130.33, 219/130.51, 219/137.PS, 219/132
• US Class Current: 219/132
• CPC Class Codes: B23K 9/1081 Arc welding by means of accumulated energy

Abstract

A method and apparatus for providing welding power is disclosed. It includes a transformer with a primary winding and an output secondary winding. The ac side of a rectifier circuit is connected to the output secondary. A battery or other energy storage device, such as a capacitor, is connected in series with the dc side of the rectifier. The series combination is disposed to be connected to the load. Preferably, an input circuit receives a 115 volt ac input. The transformer has a primary to secondary turns ratio of at least about 9:1.

Claims

1. A welding-type power supply for providing welding-type power to a load, comprising:

a transformer, having a primary winding, an output secondary winding, and a charging secondary winding;

a rectifier circuit, having an ac side connected to the output secondary and further having a dc side;

a battery connected in series with the dc side to add to the output voltage, wherein the series combination is disposed to be connected to the load;

a charging rectifier and a switch, having a control input, disposed to selectively connect the charging rectifier to at least one of the battery and the charging secondary winding; and

a controller responsive to a trigger signal from a welding torch, and having a control output connected to the control input

2. The welding-type power supply of claim 1, wherein the output secondary winding includes a plurality of taps and the welding-type power supply further comprises an output select switch disposed to selectively connect the ac side to one of the taps.

3. The welding-type power supply of claim 1, wherein the switch is a relay.

4. The welding-type power supply of claim 1, further comprising a power cord having one end in electrical communication with the primary, and the other end having a male 115 volt plug.

5. The welding-type power supply of claim 4, wherein the transformer has a primary to output secondary turns ratio of at least about 9:

1.

6. The welding-type power supply of claim 5, wherein the welding-type power supply can provide a welding current of 150 amps.

7. The welding-type power supply of claim 5, wherein the battery is a 12 volt battery.

8. The welding-type power supply of claim 1, further comprising a power cord having one end in electrical communication with the primary, and the other end having a male 115 volt plug.

9. A method of providing welding power comprising:

transforming an ac input signal into a secondary ac signal;

rectifying the secondary ac signal to produce a dc signal;

providing the dc signal in series combination with a battery to add to the output voltage, wherein the series combination is provided to the load; and

charging the battery when welding is not occurring in response to a trigger signal from a welding torch indicating the welding process is not being performed.

10. The method of claim 9, further comprising selecting a current output by selecting a turns ratio using one of a plurality taps on a transformer.

11. The method of claim 9, wherein charging comprises transforming the ac signal to produce a charging ac signal, rectifying the charging ac signal to produce a charging dc signal, and selectively applying the charging dc signal to the battery.

12. The method of claim 9, wherein transforming includes stepping the voltage down by a ratio of about 9:

1.

13. The method of claim 9, further comprising receiving a 115 volt signal as the ac input signal.

14. The method of claim 9, further comprising providing 150 amps to the load.

15. The method of claim 9, wherein providing the ac signal in series combination includes providing the ac signal in series combination with a 12 volt battery.

16. A welding-type power supply for providing welding-type power to a load, comprising:

a transformer means for transforming an ac input signal into a second ac signal;

a rectifier means for receiving the second ac signal and providing a dc signal;

an energy storage means for adding voltage to the dc signal, and connected in series with the dc signal such that the series combination is disposed to be connected to the load; and

charging means for selectively charging the energy storage means in response to a trigger signal from a welding gun.

17. The welding-type power supply of claim 16, wherein the transformer means a plurality of taps and the welding-type power supply further comprises means for selectively connecting the rectifier means to one of the taps.

18. The welding-type power supply of claim 17:

wherein the transformer means includes a charging secondary winding means for producing an ac charging signal that is part of the charging means; and

the charging means further includes means for rectifying the ac charging signal to produce a dc charging signal

19. The welding-type power supply of claim 18, further comprising a power cord means for connecting the transformer means to a 115 v outlet.

20. The welding-type power supply of claim 16, further comprising a power cord means for connecting the transformer means to a 115 v outlet.

21. The welding-type power supply of claim 16, wherein the welding-type power supply can provide a welding current of 150 amps.

22. A method of providing welding power comprising:

transforming an ac input signal into a secondary ac signal;

rectifying the secondary ac signal to produce a dc signal and;

providing the dc signal in series combination with a battery in response to a trigger signal from a gun, wherein the series combination is provided to the load.

23. A welding-type power supply for providing welding-type power to a load, comprising:

a transformer, having a primary winding and an output secondary winding;

a rectifier circuit, having an ac side connected to the output secondary and further having a dc side and;

an energy storage device; and

a switch, responsive to a trigger signal from a gun, disposed to connect the energy storage device in series with the dc side to add to the output voltage, wherein the series combination is disposed to be connected to the load.

24. The welding-type power supply of claim 23, wherein the energy storage device is a capacitor.

25. The welding-type power supply of claim 24, wherein the transformer includes a charging secondary winding, and the welding-type power supply further comprises a charging rectifier and a switch disposed to selectively connect the charging rectifier to at least one of the energy storage device and the charging transformer.

26. The welding-type power supply of claim 23, wherein the transformer has a primary to output secondary turns ratio of at least about 9:

1.

27. The welding-type power supply of claim 23, wherein the welding-type power supply can provide a welding current of 150 amps.

28. A welding-type power supply for providing welding-type power to a load, comprising:

a converting circuit that is disposed to receive an ac input and provides a dc signal and;

an energy storage device connected in series with the dc signal in response to a trigger signal from a gun to add to the output voltage, wherein the series combination is disposed to be connected to the load.

29. The welding-type power supply of claim 28, wherein the energy storage device is a capacitor.

30. A method of providing welding power comprising:

transforming an ac input signal into a secondary ac signal;

rectifying the secondary ac signal to produce a dc signal and;

providing the dc signal in series combination with an energy storage device in response to a trigger signal from a gun to add to the output voltage, wherein the series combination is provided to the load.

31. The method of claim 30, further comprising selecting a current output by selecting a turns ratio using one of a plurality taps on a transformer, and wherein the energy storage device is a capacitor.

32. A method of providing welding-type power to a load, comprising:

converting an ac input into a dc signal and;

adding an energy storage device voltage in response to a trigger signal from a gun to the dc signal to produce a signal with a combined voltage that is disposed to be connected to the load.

33. The method of claim 32, further comprising providing a welding current of 150 amps when the ac input is 115 v, and wherein the energy storage device is a capacitor.

34. A method of providing welding power comprising:

transforming an ac input signal into a secondary ac signal;

rectifying the secondary ac signal to produce a dc signal and;

providing, in response to a trigger signal from a gun, the dc signal in series combination with an energy storage device, wherein the series combination is provided to the load.

35. The method of claim 34, wherein the energy storage device is a capacitor.