Patent · US Expired

Drag cup for plasma arc torch

US5856647A · kind A · utility

70Cited by
11References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 14, 1997
Grant dateJan 5, 1999
Priority date
Expiry dateMar 14, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05H1/3489
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A drag cup for a plasma arc torch is mounted on a sleeve member of the torch tip having a conical outer surface portion converging toward the torch nozzle and electrode assembly. The drag cup includes a mounting end, a conical portion extending along the conical portion of the sleeve member, and an end radially spaced from and surrounding the torch nozzle and including an end wall spaced axially outwardly of the end of the nozzle and having an opening therethrough coaxial with the plasma jet outlet orifice in the nozzle. The opening through the end wall of the drag cup is 3 to 6 times the size of the nozzle orifice and is large enough to provide a shielding gas flow about the plasma jet without disturbing the jet and, at the same time is small enough to protect the nozzle against molten metal blow-back through the opening.

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