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.

Date of Patent:
May. 06, 1986

Filed:

Jun. 27, 1984
Applicant:
Inventor:

Willy Watermann, Dortmund, DE;

Assignee:

Kloeckner-Becorit GmbH, Castrop-Rauxel, DE;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21D / ; E21D / ; E21D / ;
U.S. Cl.
CPC ...
405295 ; 405291 ; 405302 ;
Abstract

In a roof-shield support system employed in mines, at least two levelling rams each acting between a shield frame unit and an associated gap-seal plate, the latter being arranged so as to be slidable relative to the associated shield frame unit. Each levelling ram comprises a cylinder, piston and piston rod, is arranged so that the piston rod has a longitudinal bore which is open at the piston end of the piston rod, and an elongated rod which is sealed relative to the piston rod being disposed within said bore. The bore is in use in communication with a hydraulic fluid system of the ram and after levelling has occurred by actuation of the ram the pressurized hydraulic fluid admitted into the bore applies a force to the associated gap-seal plate so as to ensure its continuing tight engagement with the adjacent shield frame unit.


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