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:
Feb. 03, 1987
Filed:
Aug. 09, 1983
Applicant:
Inventors:
Assignee:
Bochumer Eisenhutte Heintzmann GmbH & Co. Kg, Bochum, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21D / ;
U.S. Cl.
CPC ...
405290 ; 29525 ; 405303 ;
Abstract
In a hydraulically operated unit, particularly a prop for a support in an underground excavation, a thin-walled tubular jacket is pressed on an inner element which is movable in an outer tubular element so that the tubular jacket has an inner diameter which is determined with a substantial undersizing relative to the outer diameter of the inner element, and the tubular jacket is clamped on the inner element with exceeding of the flow limit of the inner element and only in a plastic expansion condition which exceeds with a reliable distance and elastic deformation region of the tubular jacket and with a sufficient residual springing part.