inverter powered plasma cutting system with fixed gas flow control

• US 7,411,149 B2
• Filed: 03/31/2006
• Issued: 08/12/2008
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Schneider, Joseph C.
• Primary Examiner(s): Paschall; Mark H
• Application Number:
  US11/278,335
• Publication Number:
  US 20070235428A1
• Time in Patent Office: 865 Days
• Field of Search: 219/121.36, 219/121.59, 219/121.39, 219/121.44, 219/121.48, 219/121.54, 219/121.55, 219/75, 219/121.57, 219/74, 315/111.21, 313/231.31, 313/231.41
• US Class Current: 219/121.54
• CPC Class Codes: B23K 10/00 Welding or cutting by means of a plasma
• CPC Class Codes: B23K 9/013 Arc cutting, gouging, scarfing or desurfacing
• CPC Class Codes: B23K 9/1006 Power supply
• CPC Class Codes: B23K 9/325 Devices for supplying or evacuating shielding gas

Abstract

A lightweight and compact plasma cutting system includes a power source having an inverter and a non-adjustable regulator enclosed within the power source. The inverter is configured to generate a power signal suitable for a plasma arc process and the non-adjustable regulator is preconfigured to deliver a fixed gas flow to a plasma torch for the plasma arc process.

Claims

1. A plasma cutting power source comprising:

a housing;

an inverter disposed within the housing and configured to receive an input power and generate a plasma cutting power therefrom;

a gas path having an inlet to receive compressed gas and an outlet connected to a torch;

a non-adjustable regulator fluidly connected in the gas path and enclosed within the housing, the non-adjustable regulator configured to provide a fixed preset gas flow to the outlet; and

a valve disposed in the gas path between the non-adjustable regulator and the outlet, wherein the valve communicates the fixed preset gas flow to the outlet only by actuation of a trigger of the plasma torch.

2. The plasma cutting power source of claim 1 further comprising an adjustable operating mode selector configured to provide a second fixed preset gas flow to the outlet upon actuation of the adjustable operating mode selector.

3. The plasma cutting power source of claim 2 wherein the fixed preset gas flow is for a cutting process and the second fixed preset gas flow is for a gouging process.

4. The plasma cutting power source of claim 2 wherein the fixed preset gas flow is greater than the second fixed preset gas flow.

5. The plasma cutting power source of claim 4 wherein the fixed preset gas flow is a cutting gas flow and the second fixed preset gas flow is a gouging gas flow.

6. The plasma cutting power source of claim 1 further comprising an air filter disposed in the gas path between the inlet and the non-adjustable regulator.

7. A plasma cutting system comprising:

a power source having an inverter configured to generate a plasma arc power;

an enclosure positioned about the inverter;

a gas delivery system disposed within the enclosure and configured to provide a fixed regulated gas flow; and

a plasma torch operatively connected to the power source and the gas delivery system, the gas delivery system constructed to provide gas flow to the plasma torch when plasma arc power is provided to the plasma torch;

wherein the gas delivery system is configured to provide an alternate fixed regulated gas flow to the plasma torch and the alternate fixed regulated gas flow has a pressure that is different than a pressure of the fixed regulated gas flow.

8. The plasma cutting system of claim 7 wherein the pressure of the alternate fixed regulated gas flow is lower than the pressure of the fixed regulated gas flow and is for a gouging process.

9. The plasma cutting system of claim 7 further comprising an operator input operatively connected to the gas delivery system and constructed to configure the gas delivery system to provide one of the fixed regulated gas flow and the alternate fixed regulated gas flow.

10. The plasma cutting system of claim 7 wherein the gas delivery system includes a non-adjustable regulator constructed to generate the fixed regulated gas flow from a compressed gas flow.

11. The plasma cutting system of claim 10 wherein the non-adjustable regulator is completely surrounded by the enclosure.

12. The plasma cutting system of claim 7 further comprising a gas filter fluidly connected to the gas delivery system and constructed to filter gas supplied from a gas source.

13. The plasma cutting system of claim 7 wherein the gas delivery system further comprises a valve constructed to open to deliver the fixed regulated gas flow to the plasma torch only upon actuation of a trigger of the plasma torch.

14. A method of controlling a plasma cutting system comprising the steps of:

powering an inverter to generate a plasma arc power;

receiving an operator desired plasma process request;

setting a fixed gas flow based on the operator desired plasma process request from a gas source to a plasma torch wherein the fixed gas flow is statically regulated within a housing of the inverter; and

preventing setting the fixed gas flow from the gas source to the plasma torch when plasma arc power is communicated to the plasma torch.

15. The method of claim 14 further comprising the step of receiving a second operator desired plasma process request and setting a second fixed gas flow from the gas source to the plasma torch, the second fixed gas flow having a lower pressure than the fixed gas flow.

16. A plasma cutting system comprising:

a power source having an inverter configured to generate a plasma arc power;

an enclosure positioned about the inverter;

a gas delivery system disposed within the enclosure and configured to provide a fixed regulated gas flow, wherein the gas delivery system includes a non-adjustable regulator constructed to generate the fixed regulated gas flow from a compressed gas flow; and

a plasma torch operatively connected to the power source and the gas delivery system, the gas delivery system constructed to provide gas flow to the plasma torch when plasma arc power is provided to the plasma torch.

17. The plasma cutting system of claim 16 wherein the non-adjustable regulator is completely surrounded by the enclosure.

18. A plasma cutting system comprising:

a power source having an inverter configured to generate a plasma arc power;

an enclosure positioned about the inverter;

a gas delivery system disposed within the enclosure and configured to provide a fixed regulated gas flow; and

a plasma torch operatively connected to the power source and the gas delivery system, the gas delivery system constructed to provide gas flow to the plasma torch when plasma arc power is provided to the plasma torch;

wherein the gas delivery system further comprises a valve constructed to open to deliver the fixed regulated gas flow to the plasma torch only upon actuation of a trigger of the plasma torch.