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. 29, 1983
Filed:
Feb. 17, 1981
Applicant:
Inventors:
Klaus Spies, Aachen-Brand, DE;
Harry J Fitzgerald, Pittsburgh, PA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21C / ; E21D / ;
U.S. Cl.
CPC ...
299 11 ; 299 12 ; 405288 ;
Abstract
A method of single-entry mining of coal and analogous minerals is disclosed, which permits substantially 100% extraction of the coal or other mineral in a seam. All operations are carried out under hydraulic steel roof supports adjacent the mine face; farther back the roof is supported by non-yielding cast-in-situ pillars of quick-setting concrete rather than coal pillars or other supports. Mining machinery for these purposes is also disclosed.