The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 09, 2000
Filed:
Aug. 06, 1998
Ian Turner, Beaconsfield, Quebec, CA;
Tony Addona, St. Leonard, Quebec, CA;
Richard Munz, Westmount, Quebec, CA;
Other;
Abstract
A method is provided for forming a molten oxide ceramic electrode for a plasma arc ignited between first and second electrodes within a plasma arc chamber, wherein the conductivity the oxide ceramic is a function of temperature alone. Following ignition of the plasma arc, a mixture is formed of a small quantity of molten oxide ceramic and a sufficiently high concentration of a volatile contaminant to render the mixture electrically conductive. The plasma arc is then transferred from one of the electrodes to the mixture. The temperature of the mixture is raised sufficiently to render the oxide ceramic electrically conductive. Finally, the volatile contaminant is progressively removed from the mixture so as to leave an electrode composed of substantially pure molten oxide ceramic.