Kenneth M Manning

US Patent:

RE297348, Aug 15, 1978

Filed:

Jul 29, 1977

Appl. No.:

5/820187

Inventors:

Kenneth G. Manning - Houston TX

Assignee:

Schlumberger Technology Corporation - New York NY

International Classification:

G01V 140

US Classification:

340 18NC

Abstract:

In the representative embodiment of the apparatus of the present invention disclosed herein, a first ported or grooved cylindrical member is coaxially disposed within a drill string for directing drilling fluids flowing through the apparatus along one or more selected flow paths. [. through. ]. . Iadd. and. Iaddend. a second ported or grooved cylindrical member. [. which. ]. is coaxially arranged in the drill string adjacent to the first member for rotation in a transverse plane cutting the flow paths to cyclically obstruct these flow paths. An electric motor is cooperatively coupled by a shaft to the rotatable member for driving this member at a selected speed for developing an acoustic signal of a desired frequency as the flow paths are momentarily obstructed at periodic intervals. To prevent jamming of the flow-controlling members which would otherwise occur should debris carried in the circulating drilling fluid become lodged therebetween, the rotating member is cooperatively coupled to the motor shaft to move away from the other member in response to significant increase in the torque required to drive the rotating member. Moreover, upon an increase of the pressure differential across the two members as might occur by an accumulation of debris or the like between the two members tending to at least slow the rotating member, the other member is arranged to move away from the rotating member.