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:
Mar. 04, 2003
Filed:
May. 10, 2001
Wayne N. Lidkea, Lively, CA;
Gregory Robert Baiden, Lively, CA;
Inco Limited, Toronto, CA;
Abstract
A method for excavating a tunnel rock face by drilling a pattern of lifter holes and line holes. The line holes ensure the grade or slope of the excavation meets specification while reducing the need for cleaning out the face. A longitudinal band of lifter holes is drilled into the tunnel face at an acute angle in relation to the substantially perpendicular reference axis emerging from the tunnel face. A series of line holes, disposed opposedly adjacent to the lifter holes, are drilled at a smaller acute angle. The lifter holes are drilled deeper than the line holes and they do not intersect. Explosives are loaded into the lifter holes. The line holes are expendable and encourage fracturing of the rock.