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.:

US 6637980 B1

PDF
Full Text
Expired
Date of Patent:
Oct. 28, 2003

Filed:

Nov. 23, 2001
Applicant:
Inventor:

Roy Lee Robertson, Jr., Delbarton, WV (US);

Assignee:

Earl Products, Inc., Proctorville, OH (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21D 2/100 ; E21D 2/000 ;
U.S. Cl.
CPC ...
E21D 2/100 ; E21D 2/000 ;
Abstract

A method and apparatus of re-tightening or retensioning a roof bolt in an underground mine serves the purpose of enabling the operator to place tension between the head of a permanent, epoxy-secured, roof bolt and the roof plate of a standard roof bolt system used to effect primary roof support in an underground mine. The method and apparatus have particular utility in mines in which drawrock or localized crumbling of shale of soft rock material is encountered as the first layer of material in the mine roof. The apparatus consists of a slotted screw member and slotted nut combination. A second embodiment of the apparatus is comprised of a slotted nut, slotted screw member, and one or more slotted spacers to be oriented between the roof bolt head and base plate. The members are turned with the appropriate tightening tool such as to apply pressure between the base plate and roof bolt head, thereby re-tensioning the roof bolt. The method of the present invention includes the steps outlined above for placement and use of the apparatus in an underground mine.


Find Patent Forward Citations

Robertson, Jr., Roy. (2003). Method and apparatus for re-tensioning a roof bolt in an underground mine (U.S. Patent No. 6637980). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/6637980

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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