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. 06, 1979
Filed:
May. 09, 1977
Applicant:
Inventor:
Michael D Pennock, Pinner, GB;
Assignee:
The British Petroleum Company Limited, Sunbury-on-Thames, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175 65 ; 175106 ; 175107 ;
Abstract
A pump is installed in a drill string above the bit and both the bit and pump are connected to the outputs of a differential gearing located therebetween. The circulation of drilling fluids is the reverse from the conventional and by operating a valve in the drill string the torque applied to the bit and pump can be controlled. Useful for drilling weak formations.