High visibility plasma arc torch

• US 7,989,727 B2
• Filed: 12/15/2006
• Issued: 08/02/2011
• Est. Priority Date: 09/13/2006
• Status: Active Grant

• Current Assignee: Hypertherm Incorporated
• Original Assignee: Hypertherm Incorporated
• Inventors: Roberts, Jesse A., Twarog, Peter J.
• Primary Examiner(s): Paschall; Mark H
• Application Number:
  US11/611,625
• Publication Number:
  US 20080083711A1
• Time in Patent Office: 1,691 Days
• Field of Search: 219/121.5, 219/121.51, 219/121.52, 219/121.48, 219/121.59, 219/74, 219/75, 313/231.31, 313/121.41, 315/111.21
• US Class Current: 219/121.48
• CPC Class Codes: H05H 1/34 Details, e.g. electrodes, nozzles
• CPC Class Codes: H05H 1/3478 Geometrical details

Abstract

An improved torch providing high visibility of the work zone to the operator, an increased viewing angle, and a reduced obstruction angle. The high visibility torch includes consumables adapted to maintain torch and consumables performance while reducing visual obstruction to the user, by coordinating, balancing, and optimizing design requirements and stack up tolerances. The invention also includes a related low-profile safety switch that promotes workpiece visibility and minimizes view obstruction.

Claims

1. An electrode for a high visibility plasma arc cutting torch comprising:

an elongated electrode body having a first end and a second end, the body defining a bore in the first end for receiving an insert, the electrode body including;

(i) a first body portion extending from the first end and having a first length and a first width; and

(ii) a second body portion extending to the second end and comprising a second length and a second width,

wherein a ratio of the second width to the first width is at least about 2, and a ratio of the first length to the first width is at least about 3.

2. The electrode of claim 1, wherein the ratio of the second width to the first width is between about 2 and 2.5.

3. The electrode of claim 1, wherein the ratio of the first length to the first width is between 3.5 and 4.5.

4. The electrode of claim 1, wherein the ratio of the first length to the first width is at least about 4.

5. The electrode of claim 1, the body having a distance from the first end to the second end that defines an overall length, such that a ratio of the first length to the overall length is at least about 0.6.

6. The electrode of claim 1, the second body portion including at least one rib that at least partially defines a cooling gas passage adjacent an exterior surface of the second body portion.

7. The electrode of claim 6, wherein the second body portion further defines a shoulder having an imperforate face that blocks passage of a gas flow through the second body portion.

8. The electrode of claim 7, wherein at least one of the cooling gas passage or the imperforate face is configured to provide a gas pressure drop sufficient to enable a motion of the electrode with respect to an anode.

9. The electrode of claim 1, wherein the first and second body portions are formed integrally of a solid material.

10. The electrode of claim 1, wherein at least one of the first width and the second width is a diameter.

11. A method of cutting a workpiece comprising the steps of:

providing a plasma arc torch comprising the electrode of claim 1; and

supplying an electrical current to the electrode to energize the torch.

12. A plasma arc torch comprising the electrode of claim 1.

13. An electrode for a high visibility plasma arc cutting torch comprising:

an elongated electrode body having a first end and a second end, a distance from the first end to the second end defining an overall length, the body defining a bore in the first end for receiving an insert, the electrode body including;

(i) a first body portion extending from the first end and having a first length and a first width; and

(ii) a second body portion extending to the second end and comprising a second length and a second width,

wherein a ratio of the second width to the first width is at least about 2, and a ratio of the first length to the overall length is at least about 0.6.

14. The electrode of claim 13, wherein the ratio of the second width to the first width is between 2 to 2.5.

15. The electrode of claim 13, wherein the ratio of the first length to the overall length is between 0.6 to 0.7.

16. The electrode of claim 13, wherein a ratio of the first length to the first width is at least about 3.

17. The electrode of claim 16, wherein the ratio of the first length to the first width is at least about 4.

18. The electrode of claim 13, the second body portion including at least one rib that at least partially defines a cooling gas passage adjacent an exterior surface of the second body portion.

19. The electrode of claim 18, wherein the second body portion further defines a shoulder having an imperforate face that blocks passage of a gas flow through the second body portion.

20. The electrode of claim 19, wherein at least one of the cooling gas passage or the imperforate face is configured to provide a gas pressure drop sufficient to enable a motion of the electrode with respect to an anode.

21. The electrode of claim 13, wherein the first and second body portions are formed integrally of a solid material.

22. The electrode of claim 13, wherein at least one of the first width and the second width is a diameter.

23. A method of cutting a workpiece comprising the steps of:

providing a plasma arc torch comprising the electrode of claim 13; and

supplying an electrical current to the electrode to energize the torch.

24. A plasma arc torch comprising the electrode of claim 13.