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:
Nov. 19, 1991
Filed:
Dec. 21, 1990
Applicant:
Inventors:
John A Meyers, New Iberia, LA (US);
David E Drake, Roscoe, TX (US);
Charles W Witt, Fort Smith, AR (US);
Assignee:
Smith International, Inc., Houston, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175414 ; 175293 ;
Abstract
A retention system is disclosed for a hammer-percussion bit assembly which prevents the loss of the lower section of bit after a crack propagates through the shank (rotational drive) section of the bit. The system includes retainer which is mounted onto the drive sub of the assembly. The retainer is adapted to extend around the head section of the bit and functions to grab the severed bit head section upon lifting of the drill string while not interfering with the normal operation of the assembly.