Patents by Inventor Antonio Fabris

Antonio Fabris has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7109719
    Abstract: An azimuthal resistivity logging tool includes one or more pads for making azimuthal resistivity measurements of earth formation. Current from the pads, guard electrodes and a measure electrode are measured while monitoring the voltage difference between pairs of monitor electrodes. The pads and an adjacent portion of the tool body form a guard electrode. In addition, microelectrodes are provided on the pads for obtaining high resolution resistivity measurements.
    Type: Grant
    Filed: May 11, 2004
    Date of Patent: September 19, 2006
    Assignee: Baker Hughes Incorporated
    Inventors: Antonio Fabris, Rashid Khokhar
  • Publication number: 20050253589
    Abstract: A resistivity logging tool includes one or more pads for making azimuthal resistivity measurements of earth formation. Current from the pads, guard electrodes and a measure electrode are measured while monitoring the voltage difference between pairs of monitor electrodes. In addition, microelectrodes are provided on the pads for obtaining high resolution resistivity measurements.
    Type: Application
    Filed: May 11, 2004
    Publication date: November 17, 2005
    Inventors: Antonio Fabris, Rashid Khokhar
  • Patent number: 6801039
    Abstract: A mud resistivity measuring device for use in a borehole includes a pair of current electrodes disposed between a pair of guard electrodes. The measure electrodes are carried on a recessed portion of a logging tool so that the measure current flows substantially along the borehole axis and is relatively insensitive to the formation resistivity. A pair of measure electrodes on the logging tool determines a voltage difference caused by the current flow in the borehole.
    Type: Grant
    Filed: May 9, 2002
    Date of Patent: October 5, 2004
    Assignee: Baker Hughes Incorporated
    Inventors: Antonio Fabris, Rashid Khokhar
  • Publication number: 20030210061
    Abstract: A mud resistivity measuring device for use in a borehole includes a pair of current electrodes disposed between a pair of guard electrodes. The measure electrodes are carried on a recessed portion of a logging tool so that the measure current flows substantially along the borehole axis and is relatively insensitive to the formation resistivity. A pair of measure electrodes on the logging tool determines a voltage difference caused by the current flow in the borehole.
    Type: Application
    Filed: May 9, 2002
    Publication date: November 13, 2003
    Applicant: Baker Hughes, Inc.
    Inventors: Antonio Fabris, Rashid Khokhar
  • Patent number: 6154704
    Abstract: A method for correcting data measured by a well logging instrument for effects of cable yo-yo. The data are first preprocessed to reduce magnitude of spatial frequency components in the data occurring within a bandwidth of axial acceleration of the logging instrument which corresponds to the cable. Then eigenvalue, of a matrix are shifted, over depth intervals where the smallest absolute value one of the eigenvalues changes sign, by an amount such that the smallest absolute value eigenvalue does not change sign. The matrix forms part of a system of linear equations by which the measurements made by the instrument are converted to values of a property of interest of earth formations. Artifacts which may remain in the data after the step of preprocessing are substantially removed by the eigenvalue shifting. In one embodiment, the step of preprocessing includes low pass filtering using a cutoff at the axial resolution limit of a sensor on the instrument.
    Type: Grant
    Filed: November 17, 1998
    Date of Patent: November 28, 2000
    Assignee: Baker Hughes Incorporated
    Inventors: Zeljko Jericevic, Antonio Fabris
  • Patent number: 6060885
    Abstract: A differential array instrument for determining selected parameters of an earth formation surrounding a borehole, including an instrument mandrel carrying a single source electrode for injecting an electrical current of a predetermined value into the formation surrounding the borehole, and an array of a plurality of measurement electrodes uniformly and vertically spaced from said source electrode along the instrument mandrel. A predetermined group of the uniformly and vertically spaced electrodes are adapted to derive first and second difference potentials between the predetermined group of electrodes, wherein successive ones of a plurality of the predetermined group of selected measuring electrodes uniformly and vertically spaced at increasing distances from the source electrode axially of the borehole are adapted to derive a plurality of the first and second difference potentials between the predetermined group of electrodes.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: May 9, 2000
    Assignee: Western Atlas International, Inc.
    Inventors: Leonty A. Tabarovsky, Antonio Fabris, Alberto G. Mezzatesta
  • Patent number: 6060886
    Abstract: An apparatus for determining radial distribution of resistivity of earth formations surrounding a wellbore. The apparatus includes a sonde mandrel having an insulating exterior surface and electrodes disposed on the insulating surface at spaced apart locations. The electrodes are connected to circuits for measuring a focused current resistivity within a predetermined longitudinal span. The electrodes are also connected to circuits for measuring electrical impedance between pairs of electrodes spaced apart at a plurality of different longitudinal spacings. The preferred embodiment includes a voltage measuring circuit interconnected between a pair of electrodes which is positioned between a closest spaced pair of electrodes connected to the impedance measuring circuits, so that a vertical resolution of the impedance measurements can be limited to approximately the axial spacing of the pair of electrodes connected to the voltage measuring circuit.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: May 9, 2000
    Assignee: Western Atlas International, Inc.
    Inventors: Leonty A. Tabarovsky, Antonio Fabris, Alberto G. Mezzatesta, Gregory B. Itskovich
  • Patent number: 5585727
    Abstract: An apparatus for measuring resistivity of an earth formation. The apparatus includes at least one source of measuring current. The source includes a delta-sigma modulator and a serial bit source coupled to the modulator. The serial bit source represents the magnitude of the measuring current at spaced apart time intervals. The apparatus includes a sensor responsive to formation current resulting from interaction of the measure current with the earth formation. The sensor is coupled to a sigma-delta modulator. The modulator is coupled to a digital mixer and a digital filter. The output of the digital filter corresponds to the magnitude of the measure current detected by the sensor sampled at spaced apart time intervals. In a preferred embodiment, the apparatus includes a plurality of current sources each having a different frequency. The sigma-delta modulator is coupled to a plurality of mixers each for demodulating one of the different source frequencies.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: December 17, 1996
    Assignee: Western Atlas International, Inc.
    Inventors: Otto N. Fanini, Antonio Fabris
  • Patent number: D341560
    Type: Grant
    Filed: June 11, 1992
    Date of Patent: November 23, 1993
    Assignee: Carraro S.p.A.
    Inventors: Antonio A. Fabris, Antonietto Raniero