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:
Dec. 05, 1989
Filed:
Apr. 04, 1988
Michael D Amos, Burton, OH (US);
David P Kovarik, Eastlake, OH (US);
George F Kub, Jr, Northfield, OH (US);
Erico International Corporation, Solon, OH (US);
Abstract
Exothermic reaction mixtures are economically ignited remotely and electrically without the use of a low ignition starting material by creating a predetermined spark gap within a matrix of such mixture and then impressing a high energy spark across the gap through the use of a capacitor discharge circuit. The mixture is contained in a graphite or ceramic vessel or crucible and is supported over a tap hole or runner by a fusible metal disk. The material of the vessel is preferably graphite which is electrically conductive. In one form of the invention, an insulated wire with a bare tip is positioned just below the top surface of the mixture and the tip spaced a predetermined distance from the wall of the vessel. The capacitor discharge circuit is then employed to fire a high energy spark through a matrix of the material across the gap formed between the wire and vessel to initiate the reaction. In another form the spark gap may be established in a small cylindrical cartridge containing the material. The cartridge may be positioned through a hole in the side wall of the mold just below or near the top of the exothermic material so that it can be filled with the material from the main body of the exothermic material.