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. 20, 2001
Filed:
Mar. 23, 1999
Applicant:
Inventors:
Daniel Lindgren, Sandviken, SE;
Per-Olof Liljebrand, Sandviken, SE;
Håkan Lindström, Torsåker, SE;
Assignee:
Sandvik AB, Sandviken, SE;
Primary Examiner:
Int. Cl.
CPC ...
E21B 1/040 ;
U.S. Cl.
CPC ...
E21B 1/040 ;
Abstract
A rock drilling tool includes a pilot bit screw threaded into a front end of a drill rod. A reamer is mounted on the outside of the pilot bit. The reamer includes a central opening having a front portion and a rear portion. The front portion is connected to the pilot bit, and the rear portion constitutes a stiffening sleeve which extends around the outside of the drill rod.