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. 02, 1986
Filed:
Dec. 21, 1984
Applicant:
Inventors:
Jozsef Nemeth, Budapest, HU;
Laszlo Belley, Budapest, HU;
Gyorgy Gergo, Pecs, HU;
Bela Sebestyen, Pecs, HU;
Zoltan Vida, Komlo, HU;
Assignees:
Gepipari Technologiai Intezet, Budapest, HU;
Other;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21C / ;
U.S. Cl.
CPC ...
299 16 ; 102330 ;
Abstract
An apparatus for breaking coal or other mineral matter from a bed thereof which comprises a string filling a bore hole which can rise steeply in this bed. The string consists of alternating breaking units and connecting pipes each braking unit having a differential piston displaced solely by the action of air pressure so that breaking slots are unblocked to discharge compressed air built up in the string. The pistons are provided with check valves to permit filling of the string.