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:
Sep. 20, 1983
Filed:
Mar. 17, 1978
Applicant:
Inventors:
Siegfried Sigott, Zeltweg, AT;
Heinrich Suessenbeck, Zeltweg, AT;
Alfred Zitz, Zeltweg, AT;
Gottfried Siebenhofer, Vienna, AT;
Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F15B / ;
U.S. Cl.
CPC ...
91405 ; 91409 ; 92110 ; 2483 / ;
Abstract
A hydraulic mine prop includes an inner piston-like prop guided within an outer cylinder-like prop, and a roof fall valve. The interior space of said inner prop communicates freely with the working chamber of the prop, and the roof fall valve is arranged outwardly on the prop and rigidly secured thereon, the valve being connected to the working chamber by an orifice provided in the prop and leading to the working chamber. The cross-sectional area of the roof fall valve in its open position.