Nozzle and method of operation for a plasma arc torch
US5317126A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 1992 |
| Grant date | May 31, 1994 |
| Priority date | — |
| Expiry date | Jan 14, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H1/3468
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
In a plasma arc cutting torch a flow of plasma gas is bypassed out of a plasma chamber, preferably at an annular gap between a pre-orifice in an inner nozzle piece and an exit nozzle orifice in an outer nozzle piece. A bypass channel formed between the inner and outer nozzle pieces directs the bypass flow to atmosphere. A metering valve or restricting orifice remote from the gap controls the amount of the bypass flow and delays the response of changes in the flow parameters in the plasma chamber to changes in the bypass flow. The pre-orifice and nozzle orifice are positioned and dimensioned to optimize the mass flow velocity and the strength of a vortex-type flow at the pre-orifice, thereby creating a virtual nozzle immediately below the electrode. The gas flow in the plasma chamber is highly uniform and very steady.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.