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:
Feb. 14, 1984
Filed:
Feb. 18, 1981
Robert A Cunningham, Bellaire, TX (US);
George E Dolezal, Friendswood, TX (US);
Hughes Tool Company, Houston, TX (US);
Abstract
An earth boring bit has features to reduce stress concentration. The earth boring bit is of the type having three bit legs, each bit leg having a depending bearing pin for rotatably carrying a cutter. An annular fillet is formed at the junction of the bearing pin and the bit leg for receiving a seal ring. To relieve stress above the fillet and on the inside surface of the bit leg, a depression is formed. The depression is formed in the inside surface of the bit leg with a lower edge commencing at the top of the fillet. The depression is curved in vertical cross-section and is located behind the backface of the cutter.