Plasma arc torch cooling system

• US 6,946,616 B2
• Filed: 04/07/2003
• Issued: 09/20/2005
• Est. Priority Date: 04/19/2002
• Status: Expired due to Term

• Current Assignee: Victor Equipment Co. (Enovis Corp.)
• Original Assignee: Thermal Dynamics Corporation (Enovis Corp.)
• Inventors: Conway, Christopher J., MacKenzie, Darrin H., Gugliotta, Mark, Kinerson, Kevin J.
• Primary Examiner(s): Walberg, Teresa J.
• Application Number:
  US10/409,651
• Publication Number:
  US 20030213783A1
• Time in Patent Office: 897 Days
• Field of Search: 219/121.48, 219/121.49, 219/121.5, 219/137.62, 219/137.63, 219/75, 219/121.59, 313/231.31
• US Class Current: 219/121.49
• CPC Class Codes: B23K 10/00 Welding or cutting by means of a plasma
• CPC Class Codes: B23K 9/291 the shielding means being a gas
• CPC Class Codes: H05H 1/28 Cooling arrangements
• CPC Class Codes: H05H 1/34 Details, e.g. electrodes, nozzles
• CPC Class Codes: H05H 1/3431 Coaxial cylindrical electrodes
• 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 1/3468 Vortex generators
• CPC Class Codes: H05H 1/3478 Geometrical details
• CPC Class Codes: H05H 1/3489 Means for contact starting

Abstract

A cooling system for a plasma arc torch is provided that comprises a coaxial fluid flow that improves cooling of components within the plasma arc torch and that provides a more compact torch design. The coaxial fluid flow, namely, the cooling fluid flow, is distributed circumferentially about the central longitudinal axis of the torch and is flowing in the same direction at any radial location from the central longitudinal axis. The cooling fluid flows distally towards the consumable components, then proximally towards the torch head, then distally again, and then proximally again for recirculation. Additionally, both the plasma gas flow and the secondary gas flow are also flowing coaxially in addition to the cooling fluid flow.

Claims

1. A plasma arc torch comprising:

a central body disposed within the plasma arc torch, the central body defining angled passages, central axial passages, distal axial passages, and proximal axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield;

an outer fluid passage formed between the anode shield and the baffle;

a shield cap disposed adjacent the baffle;

a secondary fluid passage formed between the baffle and the shield cap;

a tip disposed in a distal portion of the central body;

an electrode disposed adjacent the tip;

a plasma chamber formed between the tip and the electrode;

a secondary spacer disposed adjacent the tip; and

a secondary fluid plenum formed between the tip and the secondary orifice, wherein,

a plasma fluid flows distally through the distal axial passages in the central body and into the plasma chamber;

a secondary fluid flows distally through the proximal axial passages in the central body, into the secondary fluid passage, and into the secondary fluid plenum; and

a cooling fluid flows distally through the angled passages in the central body and into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

2. A plasma arc torch comprising:

a cathode defining a central bore;

a coolant tube disposed within the central bore of the cathode;

a central body disposed within the plasma arc torch, the central body defining angled passages, central axial passages, distal axial passages, and proximal axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield;

an outer fluid passage formed between the anode shield and the baffle;

a shield cap disposed adjacent the baffle;

a secondary fluid passage formed between the baffle and the shield cap;

a tip disposed in a distal portion of the central body;

an electrode disposed adjacent the tip, the electrode defining a central cavity;

a plasma chamber formed between the tip and the electrode;

a secondary orifice disposed adjacent the tip; and

a secondary fluid plenum formed between the tip and the secondary orifice, wherein,

a plasma fluid flows distally through the distal axial passages in the central body and into the plasma chamber;

a secondary fluid flows distally through the proximal axial passages in the central body, into the secondary fluid passage, and into the secondary fluid plenum; and

a cooling fluid flows distally through the central bore of the cathode, through coolant tube, flows proximally and into angled passages in the central body, flows distally from the angled passages into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

3. A plasma arc torch comprising:

a central body disposed within the plasma arc torch, the central body defining distal axial passages and proximal axial passages;

an anode shield disposed adjacent the central body;

a baffle disposed adjacent the anode shield;

a shield cap disposed adjacent the baffle;

a secondary fluid passage formed between the baffle and the shield cap;

a tip disposed in a distal portion of the central body;

an electrode disposed adjacent the tip;

a plasma chamber formed between the tip and the electrode;

a secondary orifice disposed adjacent the tip; and

a secondary fluid plenum formed between the tip and the secondary orifice, wherein,

a plasma fluid flows distally through the distal axial passages in the central body and into the plasma chamber; and

a secondary fluid flows distally through the proximal axial passages in the central body, into the secondary fluid passage, and into the secondary fluid plenum.

4. A plasma arc torch comprising:

a central body disposed within the plasma arc torch, the central body defining angled passages and central axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield; and

an outer fluid passage formed between the anode shield and the baffle;

wherein a cooling fluid flows distally through the angled passages in the central body and into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

5. A plasma arc torch comprising:

a cathode defining a central bore;

a coolant tube disposed within the central bore of the cathode;

a central body disposed within the plasma arc torch, the central body defining angled passages and central axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield; and

an outer fluid passage formed between the anode shield and the baffle;

wherein a cooling fluid flows distally through the central bore of the cathode, through coolant tube, flows proximally and into angled passages in the central body, flows distally from the angled passages into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

6. A plasma arc torch configured to have a plasma fluid flow path. that comprises a distal coaxial flow through the plasma arc torch, a secondary fluid flow path that comprises a distal coaxial flow through the plasma arc torch, and a cooling fluid flow that successively comprises a distal coaxial flow and a proximal coaxial flow.

7. The plasma arc torch according to claim 6, wherein the cooling fluid flow further comprises a distal coaxial flow, then a proximal coaxial flow.

8. A plasma arc torch configured to have a cooling liquid flow that successively comprises a distal coaxial flow, then a proximal coaxial flow, then a distal coaxial flow, then a proximal coaxial flow.

9. A plasma arc torch cutting system comprising:

a power supply;

a control system in communication with the power supply; and

a plasma arc torch in communication with the control system, the plasma arc torch comprising;

a cathode defining a central bore;

a coolant tube disposed within the central bore of the cathode;

a central body disposed within the plasma arc torch, the central body defining angled passages, central axial passages, distal axial passages, and proximal axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield;

an outer fluid passage formed between the anode shield and the baffle;

a shield cap disposed adjacent the baffle;

a secondary fluid passage formed between the baffle and the shield cap;

a tip disposed in a distal portion of the central body;

an electrode disposed adjacent the tip, the electrode defining a central cavity;

a plasma chamber formed between the tip and the electrode;

a secondary orifice disposed adjacent the tip; and

a secondary fluid plenum formed between the tip and the secondary orifice, wherein,

a plasma fluid flows distally through the distal axial passages in the central body and into the plasma chamber;

a secondary fluid flows distally through the proximal axial passages in the central body, into the secondary fluid passage, and into the secondary fluid plenum; and

a cooling fluid flows distally through the central bore of the cathode, through coolant tube, flows proximally and into angled passages in the central body, flows distally from the angled passages into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

10. The plasma arc torch cutting system according to claim 9, further comprising a fluid control system.

11. The plasma arc torch cutting system according to claim 9, further comprising a motion control system.

12. The plasma arc torch cutting system according to claim 9, further comprising an arc starter.

13. The plasma arc torch cutting system according to claim 9, further comprising a central control system.

14. A cartridge body for use in a plasma arc torch comprising a plurality of passageways to accommodate a coaxial liquid flow.

15. The cartridge body according to claim 14, wherein the passageways comprise angled radial passageways and outer axial passageways for the flow of a cooling fluid.

16. The cartridge body according to claim 14, wherein the passageways comprise distal axial passageways for the flow of a plasma gas.

17. The cartridge body according to claim 14, wherein the passageways comprise proximal axial passageways for the flow of a secondary gas.

18. A method of operating a plasma arc torch, the method comprising the step of conducting a plasma fluid, a secondary fluid, and a cooling fluid through a plasma arc torch structure comprising:

a central body disposed within the plasma arc torch, the central body defining angled passages, central axial passages, distal axial passages, and proximal axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield;

an outer fluid passage formed between the anode shield and the baffle;

a shield cap disposed adjacent the baffle;

a secondary fluid passage formed between the baffle and the shield cap;

a tip disposed in a distal portion of the central body;

an electrode disposed adjacent the tip;

a plasma chamber formed between the tip and the electrode;

a secondary orifice disposed adjacent the tip; and

a secondary fluid plenum formed between the tip and the secondary orifice, wherein,

a plasma fluid flows distally through the distal axial passages in the central body and into the plasma chamber;

a secondary fluid flows distally through the proximal axial passages in the central body, into the secondary fluid passage, and into the secondary fluid plenum; and

a cooling fluid flows distally through the angled passages in the central body and into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

19. A method of operating a plasma arc torch, the method comprising the step of conducting a plasma fluid, a secondary fluid, and a cooling fluid through a plasma arc torch structure comprising:

a cathode defining a central bore;

a coolant tube disposed within the central bore of the cathode;

a central body disposed within the plasma arc torch, the central body defining angled passages, central axial passages, distal axial passages, and proximal axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield;

an outer fluid passage formed between the anode shield and the baffle;

a shield cap disposed adjacent the baffle;

a secondary fluid passage formed between the baffle and the shield cap;

a tip disposed in a distal portion of the central body;

an electrode disposed adjacent the tip, the electrode defining a central cavity;

a plasma chamber formed between the tip and the electrode;

a secondary orifice disposed adjacent the tip; and

a secondary fluid plenum formed between the tip and the secondary orifice, wherein,

a plasma fluid flows distally through the distal axial passages in the central body and into the plasma chamber;

a secondary fluid flows distally through the proximal axial passages in the central body, into the secondary fluid passage, and into the secondary fluid plenum; and

a cooling fluid flows distally through the central bore of the cathode, through coolant tube, flows proximally and into angled passages in the central body, flows distally from the angled passages into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

20. A method of operating a plasma arc torch, the method comprising the step of conducting a cooling fluid through a plasma arc torch structure comprising:

a central body disposed within the plasma arc torch, the central body defining angled passages and central axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield; and

an outer fluid passage formed between the anode shield and the baffle;

wherein a cooling fluid flows distally through the angled passages in the central body and into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

21. A method of operating a plasma arc torch cutting system, the method comprising the steps of:

operating a power supply;

operating a control system in communication with the power supply; and

conducting a plasma fluid, a secondary fluid, and a cooling fluid through a plasma arc torch structure comprising;

a cathode defining a central bore;

a coolant tube disposed within the central bore of the cathode;

a central body disposed within the plasma arc torch, the central body defining angled passages, central axial passages, distal axial passages, and proximal axial passages;

an anode shield disposed adjacent the central body;

an inner cooling chamber formed between the central body and the anode shield;

a baffle disposed adjacent the anode shield

an outer fluid passage formed between the anode shield and the baffle;

a shield cap disposed adjacent the baffle;

a secondary fluid passage formed between the baffle and the shield cap;

a tip disposed in a distal portion of the central body;

an electrode disposed adjacent the tip, the electrode defining a central cavity;

a plasma chamber formed between the tip and the electrode;

a secondary orifice disposed adjacent the tip; and

a secondary fluid plenum formed between the tip and the secondary orifice, wherein,

a plasma fluid flows distally through the distal axial passages in the central body and into the plasma chamber;

a secondary fluid flows distally through the proximal axial passages in the central body, into the secondary fluid passage, and into the secondary fluid plenum; and

a cooling fluid flows distally through the central bore of the cathode, through coolant tube, flows proximally and into angled passages in the central body, flows distally from the angled passages into the inner cooling chamber, and flows proximally through the outer fluid passage and through the central axial passages.

22. A method of operating a plasma arc torch comprising the steps of:

conducting a plasma fluid coaxially through a structure of the plasma arc torch;

conducting a secondary fluid coaxially through the structure of the plasma arc torch; and

conducting a cooling liquid coaxially through the structure of the plasma arc torch, wherein the cooling liquid flows distally and proximally through the structure.