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:
Jul. 25, 1978
Filed:
Sep. 07, 1976
Jackson M Kellner, Midland, TX (US);
Smith International, Inc., Midland, TX (US);
Abstract
The eccentric journals of a tandem roller stabilizer are azimuthally positioned relative to each other by a single thread on the mandrel onto which the journals of the successive roller assemblies are screwed, the journal of each roller assembly having a like thread and together with its end plates having a length adapted to encompass a portion of the mandrel thread having a length of (n)(360) + x degrees where n is an integer and x is the desired azimuthal displacement of each roller assembly journal from the adjacent journals. Preferably x is equal to (360)/(r) degrees where r is the number of roller assemblies on the stabilizer, so that the points of stabilizer contact with the bore hole are spaced uniformly all around the stabilizer axis. The bearings supporting the rollers on the journals may be bushed only on the loaded side and be unsealed, being cooled with air bled from the stabilizer mandrel and exhausted through the bearings. Other forms of bearings can be used, e.g. a sealed antifriction bearing employing rollers for radial load and balls for axial thrust, with O rings sealing between the rollers and end plates secured to the journals. In another embodiment, full sleeve bushings take both radial load and end thrust.