Inventor · Houston, TX, US

Borislav J. Tchakarov

33Patents
10h-index
27Co-inventors
75Inventor score

Filing activity: Aug 16, 1993 → Apr 18, 2023

Most-cited inventions

PatentTitleAreaCited byStatus
US6218662A Downhole carbon dioxide gas analyzer Physics 209 Expired
US6627873B2 Down hole gas analyzer method and apparatus Physics 54 Expired
US6484801B2 Flexible joint for well logging instruments Fixed Constructions 44 Expired
US6002643A Pulser Fixed Constructions 37 Expired
US5348091A Self-adjusting centralizer Fixed Constructions 30 Expired
US5660238A Switch actuator and flow restrictor pilot valve assembly for measurement while drilling tools Fixed Constructions 24 Expired
US5934378A Centralizers for a downhole tool Fixed Constructions 18 Expired
US6903553B2 Method and apparatus for a quadrupole transmitter for directionally sensitive induction tool Physics 15 Expired
US6937022B2 Method and apparatus for a quadrupole transmitter for directionally sensitive induction tool Physics 10 Expired
US7530407B2 Rotary coring device and method for acquiring a sidewall core from an earth formation Fixed Constructions 10 Active
US10072490B1 Boundary tracking control module for rotary steerable systems Fixed Constructions 8 Active
US8570045B2 Drilling system for making LWD measurements ahead of the bit Fixed Constructions 8 Active
US5836388A Flexible joint for downhole tools Fixed Constructions 6 Expired
US7411388B2 Rotary position sensor and method for determining a position of a rotating body Electricity 5 Expired
US8171990B2 In-situ formation strength testing with coring Fixed Constructions 5 Active
US9273517B2 Downhole closed-loop geosteering methodology Fixed Constructions 5 Active
US7373994B2 Self cleaning coring bit Fixed Constructions 5 Expired
US7921913B2 Vacuum insulated dewar flask Fixed Constructions 5 Expired
US8141419B2 In-situ formation strength testing Fixed Constructions 4 Active
US7673704B2 Variable positioning deep cutting rotary coring tool with expandable bit Fixed Constructions 4 Active
US7762328B2 Formation testing and sampling tool including a coring device Fixed Constructions 3 Active
US9638819B2 Modular resistivity sensor for downhole measurement while drilling Physics 3 Active
US9851465B2 Apparatus and methods for communicating downhole data Physics 3 Active
US10648319B2 Boundary tracking control module for rotary steerable systems Fixed Constructions 2 Active
US11326437B2 Universal bottomhole assembly node (UBHAN) providing communications to and from rotary steerable systems (RSS) and real time azimuthal resistivity imaging for geosteering and pressure while drilling (FWD) for well control Fixed Constructions 2 Active

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.