Systems, methods, and apparatuses for monitoring weld quality

• US 9,089,921 B2
• Filed: 10/03/2013
• Issued: 07/28/2015
• Est. Priority Date: 11/13/2009
• Status: Active Grant

• Current Assignee: Lincoln Global Incorporated (Lincoln Electric Holdings Incorporated)
• Original Assignee: Lincoln Global Incorporated (Lincoln Electric Holdings Incorporated)
• Inventors: Daniel, Joseph A., Chantry, Bruce J.
• Primary Examiner(s): Vu, David
• Assistant Examiner(s): NGUYEN, CUONG B
• Application Number:
  US14/045,016
• Publication Number:
  US 20140038144A1
• Time in Patent Office: 663 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B23K 31/02 relating to soldering or welding dip or wave soldering in the manufacture of printed circuits H05K3/34
• CPC Class Codes: B23K 31/12 relating to investigating the properties, e.g. the weldability, of materials
• CPC Class Codes: B23K 9/095 Monitoring or automatic control of welding parameters
• CPC Class Codes: B23K 9/0953 using computing means
• CPC Class Codes: B23K 9/0956 using sensing means, e.g. optical
• CPC Class Codes: G09B 19/24 Use of tools

Abstract

An arc welder including an integrated monitor is disclosed. The monitor is capable of monitoring variables during a welding process and weighting the variables accordingly, quantifying overall quality of a weld, obtaining and using data indicative of a good weld, improving production and quality control for an automated welding process, teaching proper welding techniques, identifying cost savings for a welding process, and deriving optimal welding settings to be used as pre-sets for different welding processes or applications.

Claims

1. A system for training students learning a welding process, the system comprising a plurality of welding stations, each welding station operable to accommodate one student and including an electric arc welder with a monitor for monitoring the electric arc welder as the student uses the electric arc welder performing the welding process by creating actual welding parameters between an advancing wire and a workpiece to form a weld, said welding process being defined by a series of rapidly repeating wave shapes of command signals for said welding parameters, each wave shape constituting a weld cycle with a cycle time,

wherein said monitor comprises:

logic for segmenting each of said wave shapes into a series of time segmented states;

logic for selecting a specific wave shape state;

logic for reading a selected weld parameter occurring in said specific wave shape state at an interrogation rate over a period of time repeated during the welding process to obtain a data set for said selected weld parameter;

logic for calculating a quality value of at least one quality parameter for said selected weld parameter from said data set for each period of time;

logic for comparing each quality value to an expected quality value to determine if a difference between said quality value and said expected quality value exceeds a predetermined threshold;

logic for weighting said quality value with a magnitude weight based on said difference, and weighting said quality value with a time contribution weight based on a time contribution of said state to its wave shape, if said difference exceeds said threshold; and

logic for determining a quality score for said weld based on all of said quality values, including any weighted quality values, obtained during said welding process.

2. The system of claim 1, wherein each welding station includes access for an instructor to view the student at the welding station during the welding process.

3. The system of claim 1, wherein the system further comprises a production monitoring system that collects data from each of the electric arc welders.

4. The system of claim 3, wherein the production monitoring system logs information on each weld formed by each student.

5. The system of claim 4, wherein the production monitoring system displays the information on a display device associated with an instructor.

6. The system of claim 3, wherein the production monitoring system logs information on an amount of time spent by each student on each weld.

7. The system of claim 6, wherein the production monitoring system displays the information on a display device associated with an instructor.

8. The system of claim 3, wherein the production monitoring system logs information on an amount of wire used by each student for each weld.

9. The system of claim 8, wherein the production monitoring system displays the information on a display device associated with an instructor.

10. The system of claim 1, wherein the system further comprises a production monitoring system that collects data from each of the electric arc welders, and

wherein the production monitoring system logs the quality score for each weld formed by each student.

11. The system of claim 10, wherein the production monitoring system displays the quality score for each weld currently being formed on a display device associated with an instructor.

12. The system of claim 1, wherein said interrogation rate is 120 kHz.

13. The system of claim 1, wherein said period of time is approximately 250 ms.

14. The system of claim 1, wherein said selected weld parameter is read for all of said states.

15. The system of claim 1, wherein said selected weld parameter is at least one of a count of said measurements taken for said selected weld parameter in said period of time, a mean voltage voltage in said period of time, a root mean square voltage RMSV in said period of time, a voltage variance V_var in said period of time, a mean current current in said period of time, a root mean square current RMSI in said period of time, and a current variance I_var in said period of time,

wherein voltage=a sum of voltages measured in said period of time/said count of voltage measurements,

wherein

16. The system of claim 1, wherein said quality parameter includes a quality count average QCA for each state calculated as:

17. The system of claim 1, wherein said quality parameter includes a quality count standard deviation QCSD for each state calculated as one of:

18. The system of claim 1, wherein said quality parameter includes a quality voltage average QVA for each state calculated as:

19. The system of claim 18, wherein said quality parameter includes a quality voltage standard deviation QVSD for each state calculated as one of:

20. The system of claim 1, wherein said quality parameter includes a quality current average QIA for each state calculated as:

21. The system of claim 20, wherein said quality parameter includes a quality current standard deviation QISD for each state calculated as one of:

22. The system of claim 1, wherein said quality parameter includes a quality voltage variance average QVVA for each state calculated as:

23. The system of claim 22, wherein said quality parameter includes a quality voltage variance standard deviation QVVSD for each state calculated as one of:

24. The system of claim 1, wherein said quality parameter includes a quality current variance average QIVA for each state calculated as:

25. The system of claim 24, wherein said quality parameter includes a quality current variance standard deviation QIVSD for each state calculated as one of:

26. A system for training students learning a welding process, the system comprising a plurality of welding stations, each welding station operable to accommodate one student and including an electric arc welder with a monitor for monitoring the electric arc welder as the student uses the electric arc welder performing the welding process by creating actual welding parameters between an advancing wire and a workpiece to form a weld, said welding process being defined by a series of rapidly repeating wave shapes of command signals for said welding parameters, each wave shape constituting a weld cycle with a cycle time,

wherein said monitor comprises:

logic for segmenting each of said wave shapes into a series of time segmented states;

logic for selecting a specific wave shape state;

logic for reading a selected weld parameter occurring in said specific wave shape state at an interrogation rate over a period of time repeated during the welding process to obtain a data set for said selected weld parameter;

logic for calculating a quality value of at least one quality parameter for said selected weld parameter from said data set for each period of time; and

logic for determining a quality score for said weld based on all of said quality values obtained during said welding process, and

wherein said selected weld parameter is at least one of a count of said measurements taken for said selected weld parameter in said period of time, a mean voltage voltage in said period of time, a root mean square voltage RMSV in said period of time, a voltage variance V_var in said period of time, a mean current current in said period of time, a root mean square current RMSI in said period of time, and a current variance I_var in said period of time,

wherein voltage=a sum of voltages measured in said period of time/said count of voltage measurements,

wherein

27. The system of claim 26, wherein said monitor further comprises:

logic for comparing each quality value to an expected quality value to determine if a difference between said quality value and said expected quality value exceeds a predetermined threshold;

logic for weighting said quality value with a magnitude weight based on said difference, and weighting said quality value with a time contribution weight based on a time contribution of said state to its wave shape, if said difference exceeds said threshold; and

logic for determining a quality score for said weld based on all of said quality values, including any weighted quality values, obtained during said welding process.

28. The system of claim 26, wherein each welding station includes access for an instructor to view the student at the welding station during the welding process.

29. The system of claim 26, wherein the system further comprises a production monitoring system that collects data from each of the electric arc welders.

30. The system of claim 29, wherein the production monitoring system logs information on each weld formed by each student.

31. The system of claim 30, wherein the production monitoring system displays the information on a display device associated with an instructor.

32. The system of claim 29, wherein the production monitoring system logs information on an amount of time spent by each student on each weld.

33. The system of claim 32, wherein the production monitoring system displays the information on a display device associated with an instructor.

34. The system of claim 29, wherein the production monitoring system logs information on an amount of wire used by each student for each weld.

35. The system of claim 34, wherein the production monitoring system displays the information on a display device associated with an instructor.

36. The system of claim 26, wherein the system further comprises a production monitoring system that collects data from each of the electric arc welders, and

wherein the production monitoring system logs the quality score for each weld formed by each student.

37. The system of claim 36, wherein the production monitoring system displays the quality score for each weld currently being formed on a display device associated with an instructor.

38. The system of claim 26, wherein said interrogation rate is 120 kHz.

39. The system of claim 26, wherein said period of time is approximately 250 ms.

40. The system of claim 26, wherein said selected weld parameter is read for all of said states.

41. The system of claim 26, wherein said quality parameter includes a quality count average QCA for each state calculated as:

42. The system of claim 26, wherein said quality parameter includes a quality count standard deviation QCSD for each state calculated as one of:

43. The system of claim 26, wherein said quality parameter includes a quality voltage average QVA for each state calculated as:

44. The system of claim 43, wherein said quality parameter includes a quality voltage standard deviation QVSD for each state calculated as one of:

45. The system of claim 26, wherein said quality parameter includes a quality current average QIA for each state calculated as:

46. The system of claim 45, wherein said quality parameter includes a quality current standard deviation QISD for each state calculated as one of:

47. The system of claim 26, wherein said quality parameter includes a quality voltage variance average QVVA for each state calculated as:

48. The system of claim 47, wherein said quality parameter includes a quality voltage variance standard deviation QVVSD for each state calculated as one of:

49. The system of claim 26, wherein said quality parameter includes a quality current variance average QIVA for each state calculated as:

50. The system of claim 49, wherein said quality parameter includes a quality current variance standard deviation QIVSD for each state calculated as one of: