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:
Aug. 28, 1990
Filed:
Dec. 30, 1988
Andre Cendre, Cosne-sur-Loire, FR;
Jean Boulet, Paris, FR;
SMF International, Sur-Loire, FR;
Abstract
An actuator for an appliance associated with a ducted body, through the duct of which flows an incompressible fluid, includes a differential piston axially moveable within the duct and operatively connected to the appliance. The piston has a tubular shape and a central bore which includes a first profiled throttling portion the minimum internal diameter of which is smaller than the internal diameter of the duct. A protruding profiled element secured in the duct body is disposed coaxially with the piston and cooperates therewith for selectively increasing the loss of head of the incompressible fluid as it flows in the direction of circulation. A spring is arranged between the piston and part of the drill string for biasing the piston in a direction of movement opposite the direction of circulation of the incompressible fluid. A measurement is provided for measuring the pressure of the incompressible fluid at the first end of the drill string. The device can serve for actuation of an orientation device for orienting a drilling tool connected to a drill string. The device can also serve for actuating a stabilizer of a set of drill rods.