Electrode for a Plasma Torch

• US 20110240609A1
• Filed: 11/27/2009
• Published: 10/06/2011
• Est. Priority Date: 12/18/2008
• Status: Active Grant

• Current Assignee: Kjellberg Finsterwalde Plasma und Maschinen GmbH (Kjellberg-Stiftung)
• Original Assignee: Kjellberg Finsterwalde Plasma und Maschinen GmbH (Kjellberg-Stiftung)
• Inventors: Steudtner, Thomas, Jehnert, Katrin, Kroschwald, Martin, Reinke, Ralf-Peter, Laurisch, Frank, Krink, Volker
• Granted Patent: US 8,710,397 B2
• Time in Patent Office: Days
• US Class Current: 219/121.52
• CPC Class Codes: H05H 1/34 Details, e.g. electrodes, nozzles
• CPC Class Codes: H05H 1/3436 Hollow cathodes with internal coolant flow
• CPC Class Codes: H05H 1/3442 Cathodes with inserted tip
• CPC Class Codes: H05H 1/3478 Geometrical details

Abstract

An electrode for a plasma torch and a plasma torch head comprise an elongated electrode holder with a front surface on the electrode tip and a hole arranged in the electrode tip along a central axis through the electrode holder, and an emission insert arranged iii the hole such that an emission surface of the emission insert is exposed. The emission surface is set back relative to the front surface of the electrode holder. An electrode for a plasma torch and a plasma torch head also comprise an electrode socket and an electrode holder, the electrode socket having an internal thread, and the electrode holder having an external thread and an O-ring in a groove in the cylindrical outer surface. The electrode holder is screwed together with the electrode socket via the external thread and the internal thread and sealed by means of the O-ring.

Claims

1. An electrode for a plasma torch, comprising:

an elongated electrode holder, said electrode holder having an electrode tip, a front surface on said electrode tip, and a hole arranged in said electrode tip along a central axis through said electrode holder;

an emission insert having an emission surface, said emission insert being arranged in said hole such that said emission surface is exposed; and

said emission surface being set back relative to said front surface of said electrode holder, said emission surface having a central surface and a peripheral surface, a distance a between said central surface of said emission insert and said front surface of said electrode holder is greater than a distance b between said peripheral surface of said emission insert and said front surface of said electrode holder.

2. The electrode of claim 1 further comprising an end of said emission insert facing away from said electrode tip, said end being frustoconical.

3. The electrode of claim 1 further comprising an end of said emission insert facing away from said electrode tip, said end running frustoconically at an angle β

in the range of about 10°

to 90°

.

4. The electrode of claim 1, said hole having a conical bottom.

5. The electrode of claim 4, said conical bottom having an angle α

in the range of about 80°

to 160°

.

6. The electrode of claim 1, further comprising:

an electrode socket having an internal thread;

said electrode holder having an external thread and a groove running radially externally; and

said electrode holder being screwed together with said electrode socket via said external thread and said internal thread and sealed.

7. The electrode of claim 6 further comprising an O-ring disposed in said groove for sealing.

8. An electrode for a plasma torch, comprising:

an elongated electrode holder, said electrode holder having an electrode tip, a front surface on said electrode tip, and a hole arranged in said electrode tip along a central axis through said electrode holder;

an emission insert having an emission surface, said emission insert being arranged in said hole such that said emission surface is exposed; and

said emission surface being set back relative to said front surface of said electrode holder, said emission surface including a central surface and a peripheral surface, said peripheral surface being inclined.

9. The electrode of claim 8 further comprising an end of said emission insert facing away from said electrode tip, said end being frustoconical.

10. The electrode of claim 9 further comprising an end of said emission insert facing away from said electrode tip, said end running frustoconically at an angle β

in the range of about 10°

to 90°

.

11. The electrode of claim 9, said hole having a conical bottom.

12. The electrode of claim 11, said conical bottom having an angle α

in the range of about 80°

to 160°

.

13. The electrode of claim 8, further comprising:

an electrode socket having an internal thread;

said electrode holder having an external thread and a groove running radially externally; and

said electrode holder screwed together with said electrode socket via said external thread and said internal thread and sealed.

14. The electrode of claim 13 further comprising an O-ring disposed in said groove for sealing.

15. An electrode for a plasma torch, comprising:

an electrode holder, said electrode holder having an end, said electrode socket being positioned to receive said end;

said electrode holder having an external thread at said end and a groove running radially externally; and

a cylindrical centring surface adjoining said groove on a side facing away from said end of said electrode holder for centring said electrode relative to said electrode socket.

16. The electrode of claim 15 further comprising:

said electrode holder being elongated and having an electrode tip, a front surface on said electrode tip, and a hole positioned at said electrode tip along a central axis through said electrode holder; and

an emission insert positioned in said hole such that an emission surface of said emission insert is exposed, said emission surface being set back relative to said front surface of said electrode holder.

17. The electrode of claim 16, said emission surface comprising a central surface and a peripheral surface.

18. The electrode of claim 17, a distance a between said central surface of said emission insert and said front surface of said electrode holder is greater than a distance b between said peripheral surface of said emission insert and said front surface of said electrode holder.

19. The electrode of claim 17, said peripheral surface being inclined.

20. The electrode of claim 16 further comprising an end of said emission insert facing away from said electrode tip, said end being frustoconical.

21. The electrode of claim 16 further comprising an end of said emission insert facing away from said electrode tip, said end running frustoconically at an angle β

in the range of about 10°

to 90°

.

22. The electrode of claim 16, said hole having a conical bottom.

23. The electrode of claim 22, said conical bottom having an angle α

in the range of about 80°

to 160°

.

24. The electrode of claim 15, further comprising:

an electrode socket having an internal thread;

said electrode holder having an external thread and a groove running radially externally; and

said electrode holder being screwed together with said electrode socket via said external thread and said internal thread and sealed.

25. The electrode of claim 24 further comprising an O-ring disposed in said groove for sealing.

26. A plasma torch head comprising:

an electrode and an elongated electrode holder, said electrode holder having an electrode tip, a front surface on said electrode tip, and a hole arranged in said electrode tip along a central axis through said electrode holder;

an emission insert having an emission surface, said emission insert being arranged in said hole such that said emission surface is exposed; and

said emission surface being set back relative to said front surface of said electrode holder, said emission surface having a central surface and a peripheral surface, a distance a between said central surface of said emission insert and said front surface of said electrode holder is greater than a distance b between said peripheral surface of said emission insert and said front surface of said electrode holder.

27. The plasma torch head of claim 26 further comprising an end of said emission insert facing away from said electrode tip, said end being frustoconical.

28. The plasma torch head of claim 26 further comprising an end of said emission insert facing away from said electrode tip, said end running frustoconically at an angle β

in the range of about 10°

to 90°

.

29. The plasma torch head of claim 26, said hole having a conical bottom.

30. The plasma torch head claim 29, said conical bottom having an angle α

in the range of about 80°

to 160°

.

31. The plasma torch head of claim 26, further comprising:

an electrode socket having an internal thread;

said electrode holder having an external thread and a groove running radially externally; and

said electrode holder being screwed together with said electrode socket via said external thread and said internal thread and sealed.

32. The plasma torch head of claim 31 further comprising an O-ring disposed in said groove for sealing.

33. A plasma torch head, comprising:

an electrode and an elongated electrode holder, said electrode holder having an electrode tip, a front surface on said electrode tip, and a hole arranged in said electrode tip along a central axis through said electrode holder;

an emission insert having an emission surface, said emission insert being arranged in said hole such that said emission surface is exposed; and

said emission surface being set back relative to said front surface of said electrode holder, said emission surface including a central surface and a peripheral surface, said peripheral surface being inclined.

34. The plasma torch head of claim 33 further comprising an end of said emission insert facing away from said electrode tip, said end being frustoconical.

35. The plasma torch head of claim 34 further comprising an end of said emission insert facing away from said electrode tip, said end running frustoconically at an angle β

in the range of about 10°

to 90°

.

36. The plasma torch head of claim 34, said hole having a conical bottom.

37. The plasma torch head of claim 36, said conical bottom having an angle α

in the range of about 80°

to 160°

.

38. The plasma torch head of claim 33, further comprising:

an electrode socket having an internal thread;

said electrode holder having an external thread and a groove running radially externally; and

said electrode holder being screwed together with said electrode socket via said external thread and said internal thread and sealed.

39. The plasma torch head of claim 33 further comprising an O-ring disposed in said groove for sealing.

40. A plasma torch head comprising:

an electrode and an electrode holder, said electrode holder having an end, said electrode socket being positioned to receive said end;

said electrode holder having an external thread at said end and a groove running radially externally; and

a cylindrical centring surface adjoining said groove on a side facing away from said end of said electrode holder for centring said electrode relative to said electrode socket.

41. The plasma torch head of claim 40 further comprising:

said electrode holder being elongated and having an electrode tip, a front surface on said electrode tip, and a hole positioned at said electrode tip along a central axis through said electrode holder; and

an emission insert positioned in said hole such that an emission surface of said emission insert is exposed, said emission surface being set back relative to said front surface of said electrode holder.

42. The plasma torch head of claim 41, said emission surface comprising a central surface and a peripheral surface.

43. The plasma torch head of claim 42, a distance a between said central surface of said emission insert and said front surface of said electrode holder is greater than a distance b between said peripheral surface of said emission insert and said front surface of said electrode holder.

44. The plasma torch head of claim 42, said peripheral surface being inclined.

45. The plasma torch head of claim 41 further comprising an end of said emission insert facing away from said electrode tip, said end being frustoconical.

46. The plasma torch head of claim 41 further comprising an end of said emission insert facing away from said electrode tip, said end running frustoconically at an angle β

in the range of about 10°

to 90°

.

47. The plasma torch head of claim 41, said hole having a conical bottom.

48. The plasma torch head of claim 47, said conical bottom having an angle α

in the range of about 80°

to 160°

.

49. The plasma torch head of claim 40, further comprising:

an electrode socket having an internal thread;

said electrode holder having an external thread and a groove running radially externally; and

said electrode holder being screwed together with said electrode socket via said external thread and said internal thread and sealed.

50. The plasma torch head of claim 49 further comprising an O-ring disposed in said groove for sealing.