ANTENNA FOR TOOLS OF GEOPHYSICAL RESEARCH IN WELL BOTTOM AND METHOD OF MANUFACTURE THEREOF Russian patent published in 2019 - IPC H01Q1/04 G01V3/26 E21B47/13 

FIELD: physics.

SUBSTANCE: invention relates to electromagnetic well logging. In particular, the proposed antenna unit, containing: bobbin configured to be placed around the outer surface of the mandrel for fastening the tool and having an outer surface of the bobbin; coil comprising a plurality of windings wound around a bobbin along at least a portion of the outer surface of the bobbin; and many ferrites located in the groove made on the outer surface of the mandrel for fastening the tool. Specified set of ferrites extends around the circumference around the outer surface and between the mandrel to secure the tool and the coil. In addition, the antenna unit contains one or more separators located in a groove that separate a plurality of ferrites and extend radially outward from the groove.

EFFECT: proposed invention provides a circuit with a large effective distance of the magnetic permeability for the magnetic field and shielding the coil windings from a weighted drill pipe coupling, protecting against associated losses by preventing the formation of a continuous magnetic induction line between adjacent ferrites.

19 cl, 7 dwg