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:
May. 06, 1986
Filed:
May. 20, 1983
Richard H Grappendorf, Riverton, UT (US);
Norton Christensen, Inc., Salt Lake City, UT (US);
Abstract
Shortening of the bit life and premature failure of cutting elements on a rotating bit near or at the gage of the bit can be avoided by disposition of the cutting elements at or below a key level on the shoulder-to-gage transition. A first tooth is placed on the shoulder of a rotating bit at the key level. The key level is defined as that point on the shoulder of the rotating bit at which a tooth extends radially from the axis of the rotating bit by a distance substantially equal to the diameter of the bore drilled by the rotating bit as also defined by the gage diameter of the rotating bit. Below the key level the teeth are set on the pads in a staggered pattern that serve to increase effective cutting element concentration. The staggered pattern is repeated within a pad and between pads in selected areas. Distinguishable cutting elements are alternated within the pattern.