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. 14, 2000
Filed:
Jun. 11, 1998
Steven Weaver, Maryland, AU;
Michael McLean, Lambton, AU;
Sandvik AB, Sandviken, SE;
Abstract
An extension drilling system for use with a semiautomatic drilling rig. The drilling system includes a plurality of extension rods constituting a drill rod string and having cooperating male and female threaded couplings therebetween, and being right-hand rope threaded couplings. A reversible drive chuck of a drilling rig drives (either directly, or via an adaptor), the outside of the female threaded end of an associated extension rod. A gripper grips one of the extension rods to hold the drill rod string stationary when the chuck is driven in reverse. The gripper is located such that only one threaded coupling is disposed between the chuck and grippers and to ensure that when the chuck is rotated in reverse, only the desired coupling is uncoupled. The drill rods have axial passages therethrough in communication with each other and through which flushing fluid is delivered to an associated drill bit and a non-return valve is incorporated in the passage through at least one of the drill rods. A socket of the drive chuck (or adaptor) is configured to automatically lock the drill rod in the socket in response to rotation of the drive chuck.