Nozzle shield for a plasma arc torch
US4861962A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1988 |
| Grant date | Aug 29, 1989 |
| Priority date | — |
| Expiry date | Jun 7, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H1/3478
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A plasma arc cutting torch, particularly one operating in the 0-200 ampere range, has a shield mounted at its lower end adjacent a workpiece to block splattered molten metal from reaching a nozzle of the torch. The shield is electrically insulated, preferably by mounting it on an insulating ring that is itself secured on a cap screwed onto the torch body. A secondary gas flow through the torch passes through the space between the nozzle and the shield to provide cooling. Bleed ports in the shield allow an enhanced flow rate with the remaining flow being at a rate, in conjunction with the size of an exit orifice in the shield, to stabilize the plasma arc. Canted ports in the secondary gas flow path produce a swirling of the gas flow which enhances the quality of the cut.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.