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:
Aug. 17, 1999
Filed:
Feb. 19, 1997
Graham Mensa-Wilmot, Houston, TX (US);
Carl W Keith, Spring, TX (US);
Smith International, Inc., Houston, TX (US);
Abstract
A drill bit adapted to walk predictably during drilling is disclosed, comprising: a bit body having a longitudinal axis and a bit face having an active zone and a passive zone, and a plurality of cutters on the bit face, a first portion of said cutters being positioned in the active zone and a second portion of said cutters being positioned in the passive zone, the first portion of cutters being more aggressive than the second portion. This the difference in aggressiveness of cutters in the first and second portions is achieved by maximizing the effect of one or more of seven features of the bit. These features include: cutter size, cutter tip profile, blade relationship, cutting structure, back rake, gage pad design and balance. Application of the principles of the present invention result in a large imbalance vector being oriented toward the leading half of the active zone.