Electromagnetic (e.g., Eddy Current) Patents (Class 702/38)
  • Patent number: 7695212
    Abstract: A ball and socket joint for a motor vehicle, with a housing (4) having a wall (7), a bottom (8) and an opening (9), with a ball pivot (3), which has a joint ball (1) and a pivot (2). The ball pivot is mounted with the joint ball (1) rotatably and pivotably in the housing (4) and the pivot extends out of the housing (4) through the opening (9). An electronic component (14) is arranged in the housing (4). An electrically conductive connection (17) is arranged in the housing (4) and is electrically connected to the component (14). The electrically conductive connection (17) extends out of the housing (4) from the component (14) in the area of the opening (9) or through the opening (9).
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: April 13, 2010
    Assignee: ZF Friedrichshafen AG
    Inventors: Joachim Spratte, Metin Ersoy
  • Patent number: 7689030
    Abstract: A method for inspecting a component having a surface profile that includes a local minima and a local maxima. The method includes generating a raw image of a component under test utilizing an eddy current inspection system, decomposing the raw image into a plurality of images wherein each image includes a different frequency component, and reconstructing at least one final image of the component that includes frequency components that are relevant to an eddy current flaw signal.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: March 30, 2010
    Assignee: General Electric Company
    Inventors: Ui Won Suh, Gigi Olive Gambrell, William McKnight, Preeti Pisupati
  • Publication number: 20100042336
    Abstract: If surface defects, near surface defects, or internal defects of a ferromagnetic substance object, a paramagnetic substance object, or a mixture object of ferromagnetic and paramagnetic substances are not quantitatively analyzed, the detected results can be differently analyzed depending on the knowledge or skill of an inspector. A defect detection apparatus according to an exemplary embodiment of the present invention includes an induced current applier, a magneto-electric converter, a signal processor, a signal converter, and a data processor. The induced current applier applies a line or surface current to an object that is to be measured by using an alternating current (AC) having a frequency varying depending on a depth to be measured. The magneto-electric converter senses a magnetic field generated from the object by the Hn e or surface current and generates a magnetic field sensing signal corresponding to a strength of the sensed magnetic field.
    Type: Application
    Filed: August 7, 2007
    Publication date: February 18, 2010
    Inventors: Jin-Yi Lee, Jong-Woo Jun, Ji-Seong Hwang
  • Patent number: 7657389
    Abstract: A system and method using a touch probe device for eddy current inspection. The touch probe provides a simple approach for coming within close contact of the specimen while maintaining a normal angle and pressure at the right positions. The use of the touch probe further reduces the total time for the eddy current inspection. The touch probe aligns the probe to a specimen to be inspected, for the purpose of reducing measurement errors and increasing productivity.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: February 2, 2010
    Assignee: General Electric Company
    Inventors: Ui W. Suh, Richard C. Knepfle
  • Patent number: 7634392
    Abstract: A method and system for simulating defects in conduits, where the defects are detected using long-range guided-wave inspection techniques. The guided wave interaction with a defect is treated as a one-dimensional problem of plane wave reflection from a boundary of different acoustic impedances. The defect waveform is simulated using an electrical transmission line model and inverse fast Fourier transformation.
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: December 15, 2009
    Assignee: Southwest Research Institute
    Inventors: Hegeon Kwun, Sang-Young Kim, Myoung-Seon Choi
  • Publication number: 20090301206
    Abstract: The invention relates to a method for nondestructive testing of a metallic workpiece (11) using an ultrasonic transducer testing head having the following steps: to generate an ultrasonic wave, an excitation pulse is transmitted using the ultrasonic transducer (1) to the workpiece (11), a response signal is measured using the magnetic field sensor (3), testing information, preferably transit time information of the ultrasonic wave and therefrom wall thickness information about the thickness of the workpiece (11), is ascertained on the basis of an ultrasonic echo component of the response signal, and further information, in particular distance information about the distance of the testing head from the workpiece (11), is ascertained on the basis of a magnetic field component of the response signal by supplementary analysis.
    Type: Application
    Filed: November 21, 2006
    Publication date: December 10, 2009
    Inventors: Andre Yashan, Herbert Willems, Frank Niese
  • Publication number: 20090234590
    Abstract: A method of predicting at least one physical change in crack geometry based on ILI operating pressure, the method comprising a) performing a first test on a pipeline at a first pressure P1; b) obtaining a first set of test data on the pipeline at P1; c) performing a second test on the pipeline at a second pressure P2; d) obtaining a second set of test data on the pipeline at P2; and e) analyzing the first and second sets of test data for difference in feature signature at P1 vs. P2.
    Type: Application
    Filed: March 14, 2008
    Publication date: September 17, 2009
    Inventors: Richard Clark McNealy, Ming Gao
  • Publication number: 20090192730
    Abstract: To provide a damage detection apparatus and damage detection method enabling an identification of a crack at a higher speed with a nondestructive inspection method which enables a quantification of a damage such as a crack buried inside a specimen, a crack exposed on a surface, or a wall thinning of the specimen, in three dimensions with an optional aspect ratio and inclination.
    Type: Application
    Filed: January 31, 2007
    Publication date: July 30, 2009
    Applicant: NATIONAL UNIVERSITY CORPORATION OKAYAMA UNIVERSITY
    Inventor: Naoya Tada
  • Patent number: 7552810
    Abstract: A coin discrimination sensor having an excitation coil and two detector coils arranged to detect eddy currents in a passing coin. The excitation coil is provided a composite waveform formed by adding a low frequency signal (30 KHz) with a high frequency signal (480 KHz). The two detector coils are arranged at different distances from the passing coin, and are calibrated to eliminate the common-mode voltage when no coin is present. As a coin passes by the sensor, eddy currents are induced in the coin which result in phase and amplitude shifts in the low and high frequency components of the detector signal. The low and high frequency components are separated from the detector signal, and their respective phases and amplitudes are ascertained and compared against values stored in a lookup table. These values represent the composition, thickness, and diameter characteristics of known coins, and if the signature of the processed coin does not appear in the lookup table, it can be flagged as an invalid coin.
    Type: Grant
    Filed: October 12, 2004
    Date of Patent: June 30, 2009
    Assignee: Cummins-Allison Corp.
    Inventor: David J. Mecklenburg
  • Publication number: 20090164143
    Abstract: Embodiments of the present invention provide systems, program product and methods to detect crack-like features in pipeline welds using magnetic flux leakage data and pattern recognition. A screening process, for example, does not affect or change how survey data is recorded in survey tools; only how it is analyzed after the survey data is completed. Embodiments of the present invention can be used to screen for very narrow axial anomalies in the pipeline welds, and may also be used to predict the length of such anomalies. Embodiments of the present invention also produce a listing of the anomalies based on their relative signal characteristics.
    Type: Application
    Filed: November 13, 2008
    Publication date: June 25, 2009
    Inventors: Noel Duckworth, Ron Sherstan
  • Publication number: 20090150093
    Abstract: A method of synthesizing nondestructive examination data of a component that combines data sets acquired at least two different frequencies. At least one of the data sets is interpolated or extrapolated to the equivalent of data acquired at one of the other frequencies employing a third, reference set of eddy current inspection data that is acquired at each of the inspection frequencies being combined.
    Type: Application
    Filed: December 11, 2007
    Publication date: June 11, 2009
    Inventors: Warren R. Junker, Thomas W. Nenno, Daniel J. Yaklich, Ronald J. Pocratsky
  • Publication number: 20090132180
    Abstract: A fault detector for detecting valve movement of a valve in a fuel injector of an engine system, the valve comprising an electromagnetic actuator arranged to move the valve between first and second valve positions during a valve cycle, the engine system comprising a sensor for sensing a current through the actuator. The detector comprises a controller arranged to control the sensor; inputs for receiving from the sensor data related to the current through the actuator; a processor arranged to analyze the received data for current discontinuities; and outputs for outputting a valve movement signal in dependence upon the current discontinuities determined by the processor.
    Type: Application
    Filed: November 12, 2008
    Publication date: May 21, 2009
    Inventors: Daniel A. Pearce, Anthony Thomas Harcombe
  • Patent number: 7518359
    Abstract: A non-planar part has a non-planar surface such as an edge, and may contain an anomaly such as a crack. The non-planar part is inspected using an eddy current technique. The method includes providing the non-planar part having the non-planar surface thereon, driving an eddy current probe at two or more frequencies, measuring an eddy current response signal of the non-planar part at each frequency, and performing a multifrequency phase analysis on the eddy current response signals.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: April 14, 2009
    Assignee: General Electric Company
    Inventors: Changting Wang, Ui Suh
  • Publication number: 20090085585
    Abstract: An article includes an electrically conductive corrodible element; a device that can inject electricity at a plurality of operation frequencies into the corrodible element; and a measurement apparatus operable to measuring impedance of the electrically conductive corrodible element under various operation frequencies.
    Type: Application
    Filed: October 12, 2007
    Publication date: April 2, 2009
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Jilai Lu, Weiguo Chen, Brian Walter Lasiuk, Yu Zhang
  • Patent number: 7499815
    Abstract: A system and method for readily generating radial clearance data for a radial clearance between locations on at least two parts in a rotating machine includes rendering an image of a cross section view of at least a portion of the machine on a display. The locations on the two parts are identified on the rendered cross section, and a radial stack path between the identified locations is automatically determined. The radial clearance between the identified locations when the machine is not operating is determined, based at least in part on the determined radial stack path. Data generated by a deflection analysis model of the machine are used to determine radial deflections of the identified locations during machine operation at one or more machine operating conditions. Data representative of the radial clearance between the identified locations during the machine operation at the one or more machine operating conditions are generated.
    Type: Grant
    Filed: November 2, 2006
    Date of Patent: March 3, 2009
    Assignee: Honeywell International Inc.
    Inventors: Dave G. Dischinger, Charles P. Silcox, Amitabh Tandon, Muralidharan Kendai, Karthikeswaran Kalusivalingam
  • Patent number: 7496455
    Abstract: An electromagnetic flowmeter includes a measuring tube (1) through which a fluid to be measured flows, electrodes (2a, 2b) which are placed in this measuring tube and detect an electromotive force generated by a magnetic field applied to the fluid and the flow of the fluid, an exciting coil (3) and power supply unit (4) which apply a time-changing magnetic field to the fluid, a signal conversion unit (5) which extracts a ?A/?t component from the resultant electromotive force of the electromotive force based on the ?A/?t component irrelevant to the flow velocity of the fluid and the electromotive force based on a v×B component originating from the flow velocity of the fluid, which are detected by the electrodes (2a, 2b), and a flow rate output unit (6) which extracts only the v×B component by removing the extracted ?A/?t component from the resultant electromotive force, and calculates the flow rate of the fluid based on the v×B component.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: February 24, 2009
    Assignee: Yamatake Corporation
    Inventor: Tomoshige Yamamoto
  • Publication number: 20090046964
    Abstract: A technique for determining properties of a bearing assembly in use involves using an eddy current probe for detecting changes in material density within a raceway of the bearing assembly. A field of detection of the eddy current probe enters the bearing raceway intermediate races that define the raceway, and as such the detection is of the bearing elements, and not deflections in a wall that defines the raceway.
    Type: Application
    Filed: August 16, 2007
    Publication date: February 19, 2009
    Inventor: Brian Galeote
  • Patent number: 7487052
    Abstract: An exciting unit, applies, to a fluid, a time-changing magnetic field asymmetrical to a plane (PLN). An electrode is placed on the plane in a measuring tube, and detects a resultant electromotive force of an electromotive force based on ?A/?t component (A: vector potential, t: time) irrelevant to a flow velocity of the fluid and an electromotive force based on a v×B component originating from the flow velocity of the fluid. A state quantifying unit extracts the ?A/?t component and a variation factor dependent on a parameter to be detected, and quantifies the parameter on the basis of the variation factor. The characteristic and state of the fluid and the state in the measuring tube can be detected regardless of the flow rate of the fluid by using the same hardware arrangement as that of an electromagnetic induction type flowmeter.
    Type: Grant
    Filed: September 21, 2005
    Date of Patent: February 3, 2009
    Assignee: Yamatake Corporation
    Inventor: Tomoshige Yamamoto
  • Patent number: 7480574
    Abstract: The invention is directed to a system and method for detecting defects in a manufactured object. These defects may include flaws, delaminations, voids, fractures, fissures, or cracks, among others. The system utilizes an ultrasound measurement system, a signal analyzer and an expected result. The signal analyzer compares the signal from the measurement system to the expected result. The analysis may detect a defect or measure an attribute of the manufactured object. Further, the analysis may be displayed or represented. In addition, the expected result may be generated from a model such as a wave propagation model. One embodiment of the invention is a laser ultrasound detection system in which a laser is used to generate an ultrasonic signal. The signal analyzer compares the measured ultrasonic signal to an expected result. This expected result is generated from a wave propagation model. The analysis is then displayed on a monitor.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: January 20, 2009
    Assignee: Lockheed Martin Corporation
    Inventors: Marc Dubois, Peter W. Lorraine, Robert J. Filkins
  • Patent number: 7469187
    Abstract: A distortion compensation method includes determining an undisturbed phase for at least one of a first position indication signal and a second position indication signal. The method includes determining an undisturbed ratio that relates the amplitude of the first position indication signal at a first frequency to the amplitude of the second position indication signal at a second frequency. The method also includes determining a disturbed amplitude of the position indication signal and adjusting a position indication based on the disturbed amplitude and phase, the undisturbed amplitude ratio, and the undisturbed phase. The method further comprises determining a relationship between the eddy current phase of the first position indication signal and the second position indication signal.
    Type: Grant
    Filed: January 13, 2006
    Date of Patent: December 23, 2008
    Assignee: Northern Digital Inc.
    Inventors: John M. Nieminen, Stefan R. Kirsch
  • Patent number: 7467057
    Abstract: Precomputed databases of sensor responses are used to convert measurement data into properties of interest, for example, conductivity or lift-off. These databases of responses may be generated prior to data acquisition and provide sensor response values that span appropriate ranges for the property values. After data acquisition, estimates for the property values are obtained from measurement values by minimizing the difference between the database of responses and the measurement values. The minimization can take the form of a least-squares minimization. Alternatively, iterative techniques can be used to minimize the difference between the database and measurement values.
    Type: Grant
    Filed: September 15, 2005
    Date of Patent: December 16, 2008
    Assignee: JENTEK Sensors, Inc.
    Inventors: Yanko Konstantinov Sheiretov, Neil J. Goldfine, Andrew P. Washabaugh, Darrell E. Schlicker
  • Patent number: 7460963
    Abstract: Device for health monitoring of a structure comprising a dielectric material of permittivity ?r, comprising a source of electromagnetic radiation, generating an electric field in the structure a detector measuring a component of the electric field, calculation means giving the value of ?r on the basis of the said component.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: December 2, 2008
    Assignees: Centre National de la Recherche Scientifique (CNRS), Office National d'etudes et de Recherches Aerospatiales (ONERA), Ecole Normale Superieure de Cachan
    Inventors: Michel Bernard Lemistre, Dominique Marc Placko
  • Publication number: 20080228412
    Abstract: A method for nondestructive testing of the pipes for detecting surface flaws using magnetic leakage flux is disclosed. With of the method, flaws can be detected and analyzed in near-real-time while the pipe is produced. The data obtained with inductive coils, Hall sensors or GMR sensors are digitized, the digital data are buffered in a first memory, and a subset of the digital data are copied into a second memory. The copied data are transformed with a wavelet transformation and the resulting wavelet coefficients are filtered and/or modified. In an alternative embodiment, the digital data can be continuously supplied to a routine for wavelet transformation, which is performed using cascaded digital signal processing routines. The evaluated variable is compared with a reference value, wherein a determined flaw-based signal can be unambiguously associated with the position of the flaw.
    Type: Application
    Filed: July 28, 2006
    Publication date: September 18, 2008
    Applicant: V & M DEUTSCHLAND GMBH
    Inventors: Thomas Orth, Stefan Nitsche, Till Schmitte
  • Publication number: 20080215257
    Abstract: The invention relates to a method for reducing digital data which can be obtained with an electromagnetic acoustic transducer (EMAT) pig. Said method increases the fidelity of reproduction compared to traditional methods, without increasing and/or without significantly increasing the amount of data which is to be memorised. Said method enables, after the testing step, the ultrasonic envelopes to be reconstructed without a significant loss of information, from the data which is recorded in a reduced manner. Said method evaluates the size of the enveloping by method groups in order to determine the size. The size determination is discriminated in the quality thereof by the method groups in order to determine the signal base.
    Type: Application
    Filed: January 19, 2006
    Publication date: September 4, 2008
    Applicant: FORSCHUNGSZENTRUM KARLSRUHE GMBH
    Inventors: Helmut Stripf, Matthias Balzer
  • Patent number: 7400984
    Abstract: A biomagnetic measurement technique which can obtain a potential waveform corresponding to a ventricular muscle cell action potential in a non-invasive manner. The biomagnetic measurement apparatus including an operating circuit for magnetometer. The output data of the operating circuit for the magnetometer is collected and a current vector at time t is calculated. Further, an absolute value Ixy of the current vector, a potential waveform V (t) in time corresponding to depolarization of a heart from the absolute value of the current vector, and a potential waveform V (t) in a refractory period of the heart to a period corresponding to repolarization from the absolute value of the current vector are calculated.
    Type: Grant
    Filed: April 13, 2004
    Date of Patent: July 15, 2008
    Assignee: Hitachi High-Technologies, Corp.
    Inventors: Akihiko Kandori, Keiji Tsukada, Tsuyoshi Miyashita, Kuniomi Ogata
  • Patent number: 7376519
    Abstract: A method for determining damage in a structural health monitoring system comprising a plurality of sensors distributed across a structure is disclosed. The method includes decomposing the plurality of sensors into a plurality of sub-arrays. Each sub-array is associated with a current sensor. For each sub-array, data is collected, the data corresponding to electrical signals produced by waves initiated by the current sensor and detected by a receiving sensor. The data is used to calculate a damage measurement for the sub-array. Then, the damage measurement determined for each sub-array is combined to determining an overall damage assessment from the combined damage measurements.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: May 20, 2008
    Assignee: Honeywell International Inc.
    Inventors: Brent A. Morin, Grant A. Gordon, Joseph J. Nutaro, Steven R. Thompson
  • Patent number: 7356421
    Abstract: A new approach for locating an underground line described herein remains accurate in the face of bleedover by including both amplitude and phase from at least two magnetic field strength sensors in the measurement set. A numerical optimization step is introduced to deduce the positions and currents of each of several cables, of which one is the targeted cable and the others are termed bleedover cables. Furthermore, some embodiments of the method accounts for practical problems that exist in the field that relate to reliable estimation of cable positions, like the phase transfer function between transmitter and receiver, the estimation of confidence bounds for each estimate, and the rejection of false positive locates due to the presence of noise and interference.
    Type: Grant
    Filed: April 6, 2005
    Date of Patent: April 8, 2008
    Assignee: Metrotech Corporation, Inc.
    Inventors: Thorkell Gudmundsson, Jim Waite, Johan Överby, Stevan Polak, Niklas Lindstrom
  • Publication number: 20080040053
    Abstract: A method for inspecting an object is provided. The method includes applying a pulsed excitation signal to the object and detecting a transient response signal to the pulsed excitation signal. The method also includes convolving the transient response signal with a plurality of orthogonal functions to generate a plurality of orthogonal components.
    Type: Application
    Filed: August 10, 2006
    Publication date: February 14, 2008
    Inventor: Yuri Alexeyevich Plotnikov
  • Patent number: 7289913
    Abstract: Local features such as cracks in materials are nondestructively characterized by measuring a response with an electromagnetic sensor and converting this response into a selected property using a database. The database is generated prior to data acquisition by using a model to generate a baseline response or field distribution for the sensor and combining these results with another model, which may be simpler than the first model or provide a local representation of the field perturbations around a feature, which is evaluated multiple times over a range of values of the selected property. In addition, the presence of a feature may be detected by converting the sensor response into a reference parameter, such as a lift-off factor that reflects the sensor position relative to a material edge, and using this parameter to determine a reference response that can be compared to the measured response.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: October 30, 2007
    Assignee: JENTEK Sensors, Inc.
    Inventors: Darrell E. Schlicker, Neil J. Goldfine, Andrew P. Washabaugh, Yanko K. Sheiretov, Mark D. Windoloski
  • Patent number: 7275015
    Abstract: A method and a device for determining motion parameters of a conductive, profiled surface (22) relative to a sensor (3), with the sensor (3) comprising at least one coil for generating an electromagnetic alternating field, which is subjected, because of the feedback resulting from position changes between the surface (22) and the sensor (3), to a variation, which is determined by means of the coil (16). The position change is derived from the coupling impedance (Zc) of the coil (16), and the real component (Rc) and the imaginary component (Xc) of the complex coupling impedance (Zc) of the coil (16) are determined, with a distance d between the sensor (3) and the surface (22) being computed based on the determined values while using an algorithm as a basis.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: September 25, 2007
    Assignee: Micro-Epsilon Messtechnik GmbH & Co. KG
    Inventors: Stanislav Medinkov, Mark Netchaewskij, Felix Mednikov, Werner Grömmer, Martin Sellen
  • Patent number: 7275003
    Abstract: The present invention relates to a method of diagnosing deterioration by comparing an index value which is obtained by dividing the relative harmonic content of each order of the current harmonics flowing into an electric motor and inverter by the total harmonic distortion of the current harmonics up to the predetermined order, with a criteria value which is obtained by multiplying a harmonic function of each order formed of the index value by a calculated value for diagnosis of each order found through calculation from the relative harmonic content of each order. In the method, the degrees of deterioration of the electric motor and inverter are distinguished from each other by weighting the criteria value, and the deteriorated part is determined by a specific harmonic order of the current harmonics.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: September 25, 2007
    Assignee: ATEC Co. Ltd.
    Inventor: Hiroshi Koh
  • Patent number: 7243058
    Abstract: A circuit (90) and method are presented to accurately determine a BEMF voltage of a VCM coil (20) after termination of a driving current in a first current direction in the coil (20). The circuit includes a circuit for activating selected VCM coil driver transistors (44–47) to apply a current to the coil (20) in a direction opposite the first current direction to generate a magnetic field to oppose eddy currents established in structures adjacent the coil (20) by the driving current. The time that the eddy current opposing current may be applied may be determined, for example, by determining a magnitude of the original current command, a time that the coil spends in flyback, or a magnitude of the original driving current, and adjusting the time of application of the eddy current opposing current accordingly.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: July 10, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Tan Du, John K. Rote
  • Patent number: 7209844
    Abstract: A first magnetic field generated by a first coil operatively associated with a first portion of a vehicle interacts with at least one conductive element operatively associated with or at least a part of a second portion of the vehicle so as to generate an eddy current in the conductive element, which affects the magnetic field sensed by a magnetic sensor. A conductive element operatively coupled to a portion of the vehicle susceptible to a crash, e.g. a bumper or a door, provides for sensing a crash with the signal from the magnetic sensor. In another aspect, a second magnetic field is generated in the frame of a vehicle by a second coil wherein the frame is adapted so that the reluctance of the associated magnetic circuit is responsive to a crash. Signals from the first or second coils may be used to sense the associated magnetic fields.
    Type: Grant
    Filed: September 20, 2004
    Date of Patent: April 24, 2007
    Assignee: Automotive Systems Laboratory, Inc.
    Inventors: William D. Merrick, William Todd Watson, Timothy J. Bomya, Leonard S. Cech
  • Patent number: 7174256
    Abstract: The magnetoinductive flowmeter measures the flow volume of a medium traveling through a measuring tube, with a magnet that serves to generate a magnetic field permeating the measuring tube that has a magnetic-field component that extends perpendicular to the direction of flow. The flowmeter also includes a first measuring electrode and a second measuring electrode for collecting a voltage induced in the medium, a reference electrode, as well as a preamplifier to which the potentials collected by the two measuring electrodes are fed. A control circuit element is provided for controlling the common-mode input voltage of the preamplifier and/or the potential span of the dynamic range of the preamplifier in such fashion that the said common-mode input voltage of the preamplifier corresponds to approximately half the maximum output voltage of the preamplifier. This concept also permits the use of preamplifiers that operate with a low supply voltage such as 0/5 V. A measuring method is also disclosed.
    Type: Grant
    Filed: November 1, 2004
    Date of Patent: February 6, 2007
    Assignee: Krohne A.G.
    Inventors: Helmut Brockhaus, Wilhelm Florin
  • Patent number: 7110891
    Abstract: Magnetic signature measurements are taken at various points corresponding to an original water depth beneath a ship. A computer processor receives and processes (i) this group of measured magnetic signature values and (ii) the designed magnetic signature value the sensing of which actuates the subject magnetic mine, implementing graph display management on a user interface display screen. According to the computer processing, some or all such measured magnetic signature values are extrapolated at different depths each greater than the original depth, thereby yielding several or many groups, each group being of extrapolated magnetic signature values associated with various points corresponding to the same depth, the groups collectively representing a three-dimensional arrangement of extrapolated magnetic signature values associated with various points corresponding to different depths.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: September 19, 2006
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Paulo Bertell Tarr
  • Patent number: 7089130
    Abstract: Two centerlines each of which goes through the center of a surface and is parallel to one of the coordinate axes are considered for each surface constituting a cell. If one of the centerlines intersects a boundary, a line which goes through the intersection and is orthogonal to the centerline is approximated as a new boundary. If a boundary intersects with each of the two centerlines, an orthogonal line expressed by each of two lines which is obtained by crossing each of the two centerlines parallel to each different coordinate axis and a boundary is approximated as a new boundary. Thus, the new boundary is expressed by each part of these orthogonal lines toward the centerline from their intersection.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: August 8, 2006
    Assignee: Fujitsu Limited
    Inventors: Takashi Yamagajo, Takefumi Namiki
  • Patent number: 7085656
    Abstract: A technique for eliminating edge artifacts in magnetic microscopy includes the steps of scanning a SQUID over an object under study to acquire values of magnetic fields produced by currents running in the object to create a first data set having N data points. At the end of the first data set, N zero data points are added to create a second data set having 2N data points. Fast Fourier Transform (FFT) is further applied to the 2N data set to obtain k-space having b(k) values. The b(k) values of the k-space are averaged, and the averaged b(k) values corresponding to k exceeding a predetermined k value are filtered off. A set of current density representations i(k) in the k-space are obtained to which inverse FFT is applied to obtain a map of current densities I(x,y) of the object. A system for performing the method of the present invention includes a software designed to suppress (or eliminate) edge artifacts present in the obtained images.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: August 1, 2006
    Assignee: University of Maryland
    Inventors: Claudio Felipe Busko, John Matthews, Frederick Charles Wellstood
  • Patent number: 7038423
    Abstract: A method and an apparatus for controlling ride through of an induction motor by detecting a power loss from a power supply connected to the induction motor, disconnecting the induction motor from the power supply, monitoring a line voltage of the power supply, monitoring a back emf voltage generated by the induction motor and monitoring a phase differential between the line voltage and the back emf voltage. It is determined whether the monitored voltages are within a predetermined voltage limit and the phase differential is within a predetermined phase limit and the power supply is re-connected to the induction motor in response to the monitored voltages being within the predetermined voltage limit and the monitored phase differential being within the predetermined phase limit.
    Type: Grant
    Filed: September 20, 2004
    Date of Patent: May 2, 2006
    Assignee: Bay Controls, Inc.
    Inventors: Thomas A. Reed, Douglas A. Wittenmyer
  • Patent number: 6962087
    Abstract: There is described herein a method of obtaining a measure of flow from an electromagnetic flow meter having at least one field generating coil and potential sensing electrodes. A composite excitation waveform is applied to the field-generating coil. The composite excitation waveform comprises at least two frequency components and a plurality of frequency components are simultaneously present for at least a portion of the waveform. The potential sensed by the potential sensing electrodes is sampled to produce a sampled output and the sampled output is correlated with a composite waveform based on the composite excitation waveform. The result of the correlating is used to derive a measure of flow.
    Type: Grant
    Filed: April 2, 2004
    Date of Patent: November 8, 2005
    Assignee: ABB Limited
    Inventor: Troy Wray
  • Patent number: 6959267
    Abstract: A method of inspecting a heat exchanger including a plurality of tubes having ends fixed in a tubesheet includes the steps of: establishing a baseline for each tube of its location in the tubesheet and its unique eddy current pattern resulting, at least in part, from fixing the tube end in the tubesheet; inserting an eddy current probe into a first identified tube; obtaining eddy current data for the first identified tube in the region of the tubesheet; comparing the eddy current data obtained for the first identified tube with the baseline eddy current data for the tube, in order to verify the correctness of the tube identification; and accepting the obtained eddy current data if the correctness of the tube identification has been verified by the comparison. A computer program product for automatically carrying out the steps of the foregoing method is also disclosed.
    Type: Grant
    Filed: April 1, 2004
    Date of Patent: October 25, 2005
    Assignee: Westinghouse Electric Co. LLC
    Inventor: Qui V. Le
  • Patent number: 6933718
    Abstract: The present invention provides a method for the direct measurement and quantification of the material volume loss on and beneath a first surface of a substrate and thus provides an accurate depiction of the profile of the substrate. The method of the invention comprises inducing multiple eddy currents in a test substrate to determine volume loss.
    Type: Grant
    Filed: June 10, 2002
    Date of Patent: August 23, 2005
    Assignee: The Boeing Company
    Inventors: Michael R. Collingwood, Steven G. Keener
  • Patent number: 6907358
    Abstract: A specimen is mounted in a multiaxis machine. An eddy current probe is also mounted in the machine for multiaxis movement relative to the specimen. The probe is aligned in situ with a target in the specimen by direct contact therebetween at multiple alignment sites corresponding with a numerical model of the specimen. Eddy current inspection of the target may then be conducted by moving the probe along multiple inspection sites of the target corresponding with the specimen model.
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: June 14, 2005
    Assignee: General Electric Company
    Inventors: Ui Won Suh, Clifford Sneed, Jr.
  • Patent number: 6885948
    Abstract: An apparatus for applying a method for managing the integration of multiple pipeline datasets into a combined dataset or superset otherwise known as an asset survey. As each dataset is integrated into the asset survey a data management module is responsible for setting the status field of each feature point dependant on its relative age, source, name and type. The field “status” has five distinct states; active, inactive, archived, super inactive and super active. Active is representative of the latest and most accurate condition of the pipeline. Inactive indicates that the record has either been superseded by better data or the record is from new data and has not yet been validated as accurate. Archived indicates the record is associated with a piece of pipe that was removed from service (i.e. cut out of the pipeline).
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: April 26, 2005
    Assignee: Baseline Technologies, Inc.
    Inventors: Bruce Robin Dupuis, Michael John Webb
  • Patent number: 6880379
    Abstract: In a method of detecting damage in materials or objects (4) the material or object is physically influenced to produce a physical change of the material or object inducing transient slow dynamics in case of damages in the material or object. Slow dynamics induced material elastic modulus changes are detected as indication of damages of the material or object. In a device for non-destructive detection of damage in materials or objects (4), an impact source (16) is provided to impact the material or object to physically influence the material or object to produce a physical change of the material or object inducing transient slow dynamics in case of damages in the material or object. A detector (2,8,10,12,14,6) is provided to detect by said slow dynamics induced material elastic modulus changes as indications of damages of the material or object.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: April 19, 2005
    Assignee: Impressonic AB
    Inventors: Claes Hedberg, Alexander Sutin, Paul A. Johnson
  • Patent number: 6873919
    Abstract: A method for machine diagnosis and, in particular, for transmission diagnosis of a machine or motor vehicle. The measurement system comprises a capturing magnet (2), on the surface of which the ferritic wear particles (3) to be detected accumulate. A binary measurement signal is produced by a reed contact (1) arranged opposite the capturing magnet (2). This measurement gives an indication of the condition of the machine or transmission.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: March 29, 2005
    Assignee: ZF Friedrichshafen AG
    Inventors: Hubert Remmlinger, Robert Ingenbleek, Gabriele Schuwerk, Rolf Schmitz
  • Patent number: 6868363
    Abstract: A method and a system for determining radial clearances in a rotating machine are provided. The rotating machine includes at least one shell, at least one rotor, and at least one stationary component. The method includes creating a finite element model for at least one component within the rotating machine, creating a cycle deck data file for the rotating machine, determining an initial clearance versus time, and determining an initial clearance versus location.
    Type: Grant
    Filed: January 14, 2003
    Date of Patent: March 15, 2005
    Assignee: General Electric Company
    Inventors: Robert Gerard Baran, Gene David Palmer, John Cleland Lavash, Norman Douglas Lathrop
  • Patent number: 6865494
    Abstract: The subject invention pertains to an imaging technique and apparatus which can utilize an array of RF probes to measure the non-resonant thermal noise which is produced within a sample, such as a body, and produce a non-resonant thermal noise correlation. The detected noise correlation is a function of the spatial overlap of the electromagnetic fields of the probes and the spatial distribution of the conductivity of the sample. The subject technique, which can be referred to as Noise Tomography (NT), can generate a three-dimensional map of the conductivity of the sample. Since the subject invention utilizes detection of the thermal noise generated within the body, the subject method can be non-invasive and can be implemented without requiring external power, chemicals, or radionuclides to be introduced into the body. The subject imaging method can be used as a stand along technique or can be used in conjunction with other imaging techniques.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: March 8, 2005
    Assignee: MRI Devices Corp.
    Inventors: G. Randy Duensing, Charles Saylor, Feng Huang
  • Patent number: 6862538
    Abstract: A system and method for establishing estimated values of a plurality of electrical parameters of a motor. The plurality of electrical parameters may be established from stator resistance data and electrical input data obtained with no load on the motor. The plurality of electrical parameters may also be established from stator resistance data, electrical input data, and motor speed data obtained at at least two load conditions of the motor. The plurality of electrical parameters may comprise rotor resistance. The system and method may also be used to estimate a plurality of operating parameters of the motor based on the estimated values of a plurality of electrical parameters of the motor. The plurality of operating parameters of a motor may comprise rotor temperature, motor torque, and motor efficiency.
    Type: Grant
    Filed: July 23, 2002
    Date of Patent: March 1, 2005
    Assignee: Reliance Electric Technologies, LLC.
    Inventor: Yehia El-Ibiary
  • Patent number: 6847901
    Abstract: An electromagnetic flowmeter includes a exciting coil, exciting section, and arithmetic processing section. The exciting coil applies a magnetic field to a fluid flowing in a pipe line. The exciting section supplies an exciting current to the coil. The arithmetic processing section calculates a measurement flow rate on the basis of the measurement signal detected from the excited fluid. The arithmetic processing section includes a measurement flow rate calculation section. In calculating a measurement flow rate from the measurement signal, the measurement flow rate calculation section corrects the flow rate calculated from the measurement signal on the basis of one of adjustment coefficients, set in advance in correspondence with current values of exciting currents, which corresponds to a current value of an exciting current by which the measurement signal is obtained.
    Type: Grant
    Filed: April 11, 2003
    Date of Patent: January 25, 2005
    Assignee: Yamatake Corporation
    Inventors: Shin Suzuki, Ichiro Mitsutake
  • Patent number: 6845330
    Abstract: An electromagnetic flowmeter includes a coil, exciting section, noise eliminating section, and arithmetic processing section. The coil applies a magnetic field to a fluid flowing in a pipe line. The exciting section supplies an exciting current to the coil. The noise eliminating section eliminates noise from a measurement signal detected from the fluid under excitation by using a differential frequency component between a commercial power frequency and an exciting frequency. The arithmetic processing section calculates a measurement flow rate on the basis of the measurement signal output from the noise eliminating section.
    Type: Grant
    Filed: April 15, 2003
    Date of Patent: January 18, 2005
    Assignee: Yamatake Corporation
    Inventors: Kouji Okuda, Shin Suzuki, Ichiro Mitsutake