Method and Apparatus For Welding With Reduced Spatter

• US 20120067859A1
• Filed: 09/16/2011
• Published: 03/22/2012
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Albrecht, Bruce P., Leiteritz, Nathan G.
• Granted Patent: US 10,183,353 B2
• Time in Patent Office: Days
• US Class Current: 219/137.R
• CPC Class Codes: B23K 9/125 Feeding of electrodes for stabilising arc B23K9/073

Abstract

A method and apparatus for reducing spatter is disclosed. A welding gun, which can be an integrated part of a welding system, includes a device, such as a solenoid or motor and roller, to slow, stop or reverse the wire. The device is activated in response to feedback indicative of a short, a short that is about to form, or the imminent clearing of a short. The detection of the short, forming of a short, or clearing of a short is in response to feedback based on current and/or voltage. Output current can also be reduced.

Claims

1. A welding gun for reducing spatter including, a path for wire through the gun, a liner, disposed about the wire path for at least a portion of the path through the gun, a solenoid, having an activated position that impinges on the wire path, and a deactivated position that does not impinge on the wire path, and a control circuit, including a feedback input and further including a control output connected to the solenoid.

2. The gun of claim 1, wherein the liner includes a widened region that acts as a buffer for wire.

3. The gun of claim 1, wherein the control circuit includes a threshold circuit.

4. The gun of claim 3, wherein the feedback input is connected to at least one of a voltage feedback signal and a current feedback signal.

5. The gun of claim 4, wherein the control circuit includes a derivative circuit connected between the feedback input and the threshold circuit.

6. The gun of claim 4, wherein the control circuit includes a time delay circuit.

7. A welding gun for reducing spatter including, a path for feeding wire through the gun, a liner, disposed about the wire path for at least a portion of the path through the gun, and at least one of a motor, electromagnetic brake, and particle brake, connected to a roller that has an active mode that impedes wire feeding and an inactive mode that does not affect wire feeding, and a control circuit, including a feedback input and further including a control output connected to the motor.

8. The gun of claim 7, wherein the at least one of the motor, electromagnetic brake, and particle brake is a brake.

9. The gun of claim 7, wherein the control circuit includes a threshold circuit.

10. The gun of claim 9, wherein the feedback input is connected to at least one of a voltage feedback signal and a current feedback signal.

11. The gun of claim 10, wherein the control circuit includes a derivative circuit connected between the feedback input and the threshold circuit.

12. The gun of claim 10, wherein the control circuit includes a time delay circuit.

13. A method of reducing spatter in a welding process comprising:

feeding a welding wire through a welding gun toward a workpiece;

sensing a welding output parameter indicative of an impending short clearing;

activating a solenoid to restrain the feeding of the welding wire in response to the sensing; and

deactivating the solenoid to cease restraining the feeding of the welding wire.

14. The method of claim 13, further comprising storing wire in a buffer after activating.

15. The method of claim 14, further comprising comparing the sensed welding output parameter to a threshold, and wherein activating includes activating the solenoid in response to the comparison.

16. The method of claim 14, wherein sensing includes sensing at least one of a welding output voltage and a welding output current.

17. The method of claim 14, further comprising determining a value indicative of a derivative of the sensed welding output parameter, and wherein activating includes activating the solenoid in response to the determining.

18. The method gun of claim 13, further comprising waiting for a predetermined time delay after activating and before deactivating.

19. A method of reducing spatter in a welding process comprising:

feeding a welding wire through a welding gun toward a workpiece;

sensing a welding output parameter indicative of an impending short clearing;

activating at least one of a motor, electromagnetic brake, and particle brake, connected to a roller to restrain the feeding of the welding wire in response to the sensing; and

deactivating the motor to cease restraining the feeding of the welding wire.

20. A welding gun for reducing spatter, comprising:

means for sensing a welding output parameter indicative of an impending short clearing;

means for restraining the feeding of the welding wire, wherein the means for restraining is responsive to the means for sensing; and

means for ceasing the restraining of the feeding of the welding wire, wherein the means for ceasing is responsive to the means for sensing.

21. The welding gun of claim 20, further comprising means for storing wire in response to the means for restraining.