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:
Jun. 30, 1998
Filed:
Sep. 03, 1996
Zhipeng Lu, Hanover, NH (US);
Elizabeth B Hackett, Lebanon, NH (US);
Hypertherm, Inc., Hanover, NH (US);
Abstract
A method of operating a plasma arc torch for marking a metallic workpiece spaced a stand-off distance from the torch utilizes a torch that includes a body, an electrode, and a nozzle mounted in the body so as to define a plasma chamber. The nozzle has a central passage and an exit orifice through which the transferred arc passes to the workpiece. The method also utilizes a plasma gas flow through the body to form a pilot arc in the plasma chamber and then to form a transferred arc between the electrode and the workpiece. The method includes forming the plasma gas flow with a selected mixture of hydrogen and an inert gas. The percentage of hydrogen in the selected mixture is between 0% and 35%. The percentage of inert gas in the selected mixture is between 100% and 65%. The inert gas may be argon.