Asymmetric consumables for a plasma arc torch

Patent metadata

Field	Value
Publication number	US-9781818-B2
Application number	US-201615350742-A
Country	US
Kind code	B2
Filing date	Nov 14, 2016
Priority date	Aug 6, 2012
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A consumable set is provided that is usable in a plasma arc torch to direct a plasma arc to a processing surface of a workpiece. The consumable set comprises a nozzle and an alignment surface. The nozzle includes: 1) a nozzle body defining a longitudinal axis extending therethrough, and 2) a nozzle exit orifice disposed in the nozzle body for constricting the plasma arc. The nozzle exit orifice defines an exit orifice axis oriented at a non-zero bevel angle relative to the longitudinal axis. The alignment surface is generally parallel to the exit orifice axis and dimensioned to align the exit orifice such that the plasma arc impinges orthogonally on the processing surface of the workpiece. The alignment surface is configured to lay at least substantially flush against a guiding surface angled relative to the processing surface of the workpiece.

First claim

What is claimed is:

1. A consumable set usable in a plasma arc torch to direct a plasma arc to a processing surface of a workpiece for cutting the workpiece, the consumable set comprising:
a nozzle including: 1) a nozzle body defining a longitudinal axis extending therethrough, and 2) a nozzle exit orifice, disposed in the nozzle body, for constricting the plasma arc, wherein the nozzle exit orifice defines an exit orifice axis oriented at a non-zero angle relative to the longitudinal axis; and
a planar alignment surface generally parallel to the exit orifice axis, the alignment surface being dimensioned to align the exit orifice such that the plasma arc impinges orthogonally on the processing surface of the workpiece to cut the workpiece; and
an opening at an exterior end of the nozzle exit orifice, wherein a center of the opening of the nozzle exit orifice is less than about 0.25 inches from the alignment surface.

2. The consumable set of claim 1 , further comprising a second alignment surface angled relative to the alignment surface, wherein the second alignment surface, in cooperation with the alignment surface, is configured to align the plasma arc to impinge orthogonally on the processing surface of the workpiece.

3. The consumable set of claim 2 , wherein the opening of the nozzle exit orifice is located on the second alignment surface.

4. The consumable set of claim 2 , further comprising a curved surface for interconnecting the alignment surface and the second alignment surface.

5. The consumable set of claim 2 , wherein the second alignment surface is configured to contact the processing surface of the workpiece.

6. The consumable set of claim 2 , further comprising a third alignment surface angled relative to the alignment surface and the second alignment surface, wherein the third alignment surface, in cooperation with the alignment surface and the second alignment surface, is configured to align the plasma arc to impinge orthogonally on the processing surface of the workpiece.

7. The consumable set of claim 1 , wherein the alignment surface is configured to lay at least substantially flush against a guiding surface of the workpiece.

8. The nozzle of claim 7 , wherein the guiding surface comprises a portion of a template attachable to the workpiece or the plasma arc torch.

9. The consumable set of claim 7 , wherein the processing surface and the guiding surface are perpendicular to each other on the workpiece and the plasma arc is adapted to impinge orthogonally on the processing surface.

10. The consumable set of claim 1 , wherein the alignment surface includes a rounded portion.

11. The consumable set of claim 10 , wherein a first distance from a first point on a geometric arc defined by the rounded portion of the alignment surface to the center of the exterior opening of the nozzle exit orifice is at least substantially equal to a second distance from a second point on the geometric arc of the rounded portion of the alignment surface to the center of the exterior opening of the nozzle exit orifice.

12. The consumable set of claim 1 , wherein the longitudinal axis of the nozzle body is oriented at an acute angle relative to the alignment surface.

13. The consumable set of claim 1 , further comprising an internal structure generally rotationally symmetric about the longitudinal axis, and an external structure rotationally asymmetric about the longitudinal axis, wherein the nozzle exit orifice is configured to pass between the internal structure and the external structure of the nozzle body for constricting the plasma arc therethrough.

14. The consumable set of claim 13 , wherein the alignment surface is located on the external structure of the nozzle body.

15. The consumable set of claim 1 , further comprising a plane parallel with the alignment surface and centered on the exit orifice axis, the plane separating a first portion of a tip of the nozzle body and a second portion of the tip of the nozzle body, the first portion of the tip of the nozzle body between the plane and the alignment surface, such that a volume of the first portion is less than or equal to about ⅓ of a volume of the second portion.

16. The consumable set of claim 15 , wherein the volume of the first portion is less than or equal to about ¼ of the volume of the second portion.

17. The consumable set of claim 15 , wherein the volume of the first portion is less than or equal to about ⅕ of the volume of the second portion.

18. The consumable set of claim 15 , wherein the alignment surface is located on an outer surface of the first portion of the tip of the nozzle body.

19. The consumable set of claim 1 , wherein the center of the exterior opening of the nozzle exit orifice is about 0.125 inches from the alignment surface.

20. A method of manufacturing a consumable set usable in a plasma arc torch to direct a plasma arc to a processing surface of a workpiece for cutting the workpiece, the method comprising:
fabricating a nozzle including a nozzle body defining a longitudinal axis extending therethrough;
forming a nozzle exit orifice in the nozzle body oriented at a non-zero angle relative to the longitudinal axis of the nozzle body, the nozzle exit orifice dimensioned for constricting the plasma arc;
locating a planar alignment surface on the nozzle body that is generally parallel to the nozzle exit orifice axis, the alignment surface being dimensioned to align the nozzle exit orifice such that the plasma arc impinges at an orthogonal angle on the processing surface of the workpiece; and
defining an opening at an exterior end of the nozzle exit orifice, wherein a center of the opening of the nozzle exit orifice is less than about 0.25 inches from the alignment surface.

Assignees

• Hypertherm Inc

Inventors

• Twarog Peter
• Darrow Clifford G
• Shipulski E Michael
• Higgens Martin

Classifications

• Y10T29/49778

  with aligning, guiding, or instruction · CPC title

• B23K10/00

  Welding or cutting by means of a plasma · CPC title

• H05H1/3405 Primary

  Arrangements for stabilising or constricting the arc, e.g. by an additional gas flow · CPC title

• H05H1/34

  Details, e.g. electrodes, nozzles · CPC title

• H05H2001/3463

  Electricity · mapped topic