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:
Oct. 24, 1989
Filed:
Sep. 19, 1988
James W Langford, Jr, Red Oak, TX (US);
Dresser Industries, Inc., Dallas, TX (US);
Abstract
A rolling cutter earth drilling bit in which integral one-piece pilot bushings provide both radial and thrust load sliding surfaces which incorporate an anti-galling material. A roller cone bit has three downwardly extending arm members which terminate in cylindrical spindles for the rolling cutters. Each spindle has a stepped configuration providing an enlarged journal section which is stepped down to provide an annular thrust shoulder and a reduced pilot pin which projects from the thrust shoulder. The rolling cutter mounted on the spindle has an enlarged rearward bearing recess which receives the journal section of the spindle and a reduced forward bearing recess which receives the spindle pilot pin. An annular thrust face corresponding generally to the spindle shoulder is between the recesses. The pilot bushing has a sleeve portion extending into the reduced forward recess of the rolling cutter in an interference fit and an integral annular rim portion extending outwardly from the sleeve portion over the thrust face. The outer surface of the rim portion contacts the annular spindle shoulder in a thrust load relationship, and the inner surface of the sleeve portion receives the pilot pin in a radial load relationship. These surfaces incorporate an anti-galling material.