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:
Mar. 17, 1992
Filed:
Mar. 27, 1991
Applicant:
Inventors:
Ronald P Anderson, Riverdale, GA (US);
Kenneth W Miller, Fayetteville, GA (US);
William S Shelton, Lithonia, GA (US);
Assignee:
The Tensar Corporation, Morrow, GA (US);
Primary Examiner:
Int. Cl.
CPC ...
E21D / ;
U.S. Cl.
CPC ...
405288 ; 4051501 ;
Abstract
A high-strength, lightweight flame-retardant and/or self-extinguishing polymer grid is provided for supplemental support of the roof and ribs of a combustible underground opening, such as within a coal mine, to prevent roof materials from falling and/or rib materials from spalling. The preferred polymer grid structure is formed of a polypropylene compounded with flame retardant additives.