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:
Oct. 24, 1978
Filed:
Sep. 28, 1977
Applicant:
Inventor:
Willy Heyer, Bochum-Gerthe, DE;
Assignee:
Gewerkschaft Eisenhutte Westfalia, Lunen, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21D / ;
U.S. Cl.
CPC ...
405296 ; 405299 ;
Abstract
A mine roof support unit comprises a floor sill, a roof cap, a goaf shield and hydraulic props supporting the roof cap above the floor sill. The goaf shield is pivotably connected to both the floor sill and the roof cap. The floor sill is provided with at least one auxiliary prop which is arranged to contact and support the roof cap only when the hydraulic props have been retracted by a predetermined amount.