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:
May. 09, 1989
Filed:
Sep. 08, 1987
Applicant:
Inventors:
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21D / ;
U.S. Cl.
CPC ...
405296 ; 405291 ; 405295 ; 403150 ;
Abstract
A roof support employs an hydraulic piston and cylinder unit as an adjustment device between the goaf shield and the roof-engaging structure. The cylinder unit is mounted to the shield with the aid of a bearing body defining a cup receiving a spherical end of the cylinder. The body also has recesses accessible via offset openings in which journals projecting from the cylinder are located. Locking pieces detachably fitted to the shield block the openings to retain the journals therein yet permit easy assembly and dismantling of the unit.