Patent · US Expired

Plasma torch with power supply for equalizing wear to prolong the lifespan of an electrode of the torch

US5393954A · kind A · utility

3Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 1994
Grant dateFeb 28, 1995
Priority date
Expiry dateApr 25, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05H1/36
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The plasma torch (10; 11, 12, 14) comprises an electrical power supply (20) with an arc circuit (21) and a coil circuit (22) which are mounted in series and with means (30) for controlling the level of the current flowing in the coil (22) consisting, inter alia, mounted in parallel with this coil (14), of a chopper consisting of a battery of capacitors (31) and of at least one electronic power switch (32) which may be placed distant from the coil. The electronic switch is preferably of the thyristor diode (321, 322) type, with a resonant turn-off circuit (31, 323). A variant of this chopper uses at least one electronic switch of the GTO thyristor type, controllable in triggering and in switching off, or at least one conventional thyristor equipped with an auxiliary extinction circuit. Application to high-power torches, for industrial, for example metallurgical, use.

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