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. 29, 1991
Filed:
May. 29, 1990
Applicant:
Inventors:
Faisal J Yousef, Houston, TX (US);
Robert F Kane, Houston, TX (US);
Joel Ham, Cypress, TX (US);
David Mildren, Houston, TX (US);
Assignee:
Sandvik Rock Tools, Inc., Bristol, VA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ; E21B / ; F16B / ; F16L / ;
U.S. Cl.
CPC ...
175415 ; 285334 ; 285390 ; 403343 ; 411414 ; 411423 ;
Abstract
A thread coupling comprises two interconnected screw threads. Each of the screw threads has a root portion shaped as a portion of an ellipse. With respect to one of the threads having such a shape, the major axis of the ellipse is longer than that of the other thread.