Patent · US Expired

Plasma torch having a longitudinally mobile arc root, and process for controlling the displacement thereof

US4847466A · kind A · utility

10Cited by
7References
13Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJan 6, 1988
Grant dateJul 11, 1989
Priority date
Expiry dateJan 6, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05H1/3494
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The invention concerns plasma torches comprising an upstream electrode (12), a downstream electrode (11), a chamber (15) for the injection of plasma producing gas, a priming electrode (13) and optionally a magnetic field coil (14), in which the upstream root of the arc is displaced on the upstream electrode. According to the invention, in order to control a continuous or reciprocating and/or an oscillatory translation, the field coil is supplied with a variable direct current, if need be a pulsatory undulatory current, and/or a diffuser is placed at the inner end of the upstream electrode which is supplied with a modulated flow of gas which it causes to whirl. Application in high power plasma torches for regularizing and rendering uniform the wear of the electrodes so as to prolong the life thereof.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.