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. 15, 1977
Filed:
Jul. 02, 1976
Applicant:
Inventors:
Wallace W Roepke, Excelsior, MN (US);
David P Lindroth, Apple Valley, MN (US);
Joseph W Rasmussen, Minneapolis, MN (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
E21C / ;
U.S. Cl.
CPC ...
299 76 ; 299 64 ; 299 85 ; 299 89 ;
Abstract
The triangular-shaped rotary head mounted on an eccentrically driven shaft rotates at a low speed in a path determined by a ring/pinion gear ratio, such that cutting tools mounted on the apices of the triangular-shaped rotary head follow a square path entering the face of the coal seam to be cut at a top corner and making a long linear vertical cut at a constant depth of approximately one and one-half times the diameter of the rotary head greatly reducing dust generation and methane ignition potential, while increasing productivity.