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:
Nov. 23, 1976
Filed:
Apr. 08, 1976
Hans-Ferdinand Bemmerl, Herne, DT;
Bochumer Eisenhutte Heintzmann & Company, Bochum, DT;
Abstract
A pit prop comprises an elongated skid adapted to lie on the floor and having a front end linkable to a support such as a face conveyor. A pair of generally parallel elongated feet flank the skid and each have a front portion which is substantially twice as wide as its rear portion. A slide fluid cylinder has a rear end secured to the rear end of the skid and a front end secured to a cross member attached to the front portions of the feet so that extension or contraction of the slide cylinder displaces the feet relative to the support. A pair of support arms each have a rear end loosely pivoted on the rear portion of the respective foot and a front end carrying a roof-engaging shield. A lift cylinder extends between each foot front portion and the respective front end of the respective arm for pressing the shield against the mine roof and the feet against the mine floor.