Hysteresis Or Eddy Current Loss Testing Patents (Class 324/222)
  • Patent number: 11712076
    Abstract: The inventive glove provides a work glove that detects the presence of AC voltage without compromising its usability as a work glove. Embodiments of the inventive glove include monopole aerials extending into the fingers of the glove. A thin flexible dielectric layer sits between the aerials and inside of the glove, acting as an electrical barrier between the aerials and the user's hand. The aerials are connected to conventional voltage detector circuitry on a circuit board located on the back of the glove. The circuit board is grounded to the user's wrist, which enhances the circuitry's ability to detect the presence of nearby AC voltage at a safe distance.
    Type: Grant
    Filed: August 12, 2020
    Date of Patent: August 1, 2023
    Inventor: Grant Edward Staples
  • Patent number: 11709150
    Abstract: A method of inspecting a material includes examining a surface of a test material with an eddy current sensor and applying an X-ray fluorescence analysis to the surface of the test material at the same location at which the eddy current examination was performed.
    Type: Grant
    Filed: December 23, 2021
    Date of Patent: July 25, 2023
    Assignee: BWXT Nuclear Operations Group, Inc.
    Inventors: Paul D. Sheldon, Wayne M. Latham, Thomas C. Mohr, Aaron C. Havener, Richard Manzini, Timothy A. Policke
  • Patent number: 11307266
    Abstract: Various examples of a high frequency, inductor and transformer core loss characterization and measurement method and system for arbitrary waveforms are disclosed herein. A system and method for determining core loss of a magnetic core can include generating a waveform to excite a first test circuit which comprises an excitation circuit, a circuit under test (CUT) comprising the magnetic core, and an inductance circuit having an inductor connected in parallel to the CUT. The method includes measuring a first current, when the first test circuit is excited. The method includes disconnecting the CUT from the first test circuit to form a second test circuit. The method includes generating the waveform to excite the second test circuit, and measuring a second current, when the second test circuit is excited. The power loss for the magnetic core is calculated based on an input voltage and the first and second measured current.
    Type: Grant
    Filed: August 28, 2020
    Date of Patent: April 19, 2022
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Yuliang Cao, Minh Ngo, Dong Dong, Rolando Burgos
  • Patent number: 11187728
    Abstract: The present disclosure provides a current sensing device, method and system, where the device is applied in a power conversion circuit. The current sensing device includes a first winding coupled to the resonant inductor, a second winding and an integrating circuit coupled to a primary winding of the transformer having a first input terminal, a second input terminal, an output terminal, and a common terminal; one terminal of the first winding is coupled to the first input terminal of the integrating circuit, the other terminal of the first winding and the other terminal of the second winding are coupled and connected to the common terminal of the integrating circuit; one terminal of the second winding is coupled to the second input terminal of the integrating circuit.
    Type: Grant
    Filed: August 27, 2019
    Date of Patent: November 30, 2021
    Assignee: DELTA ELECTRONICS, INC.
    Inventors: Da Jin, Yahong Xiong
  • Patent number: 10649051
    Abstract: A system and method for detecting a nucleus of interest in a chemical using a nuclear quadrupole resonance transition. An excitation pulse is used to excite one or more nuclei of interest, if they present in a sample, to an excited state, the energy of which depends on the magnetic field in the sample. The magnetic field in the sample is modulated, after the end of the excitation pulse, while the nuclei of interest decay from the excited state, so that the radiation they emit is frequency modulated. The frequency modulation is detected in the emitted radiation. In some embodiments a DC magnetic field is applied to the sample, during the application of the excitation pulse, to tune the frequency of the transition being excited.
    Type: Grant
    Filed: December 21, 2017
    Date of Patent: May 12, 2020
    Assignee: Raytheon Company
    Inventors: Benjamin P. Dolgin, Thomas Lavedas, Joseph J. Fraundorfer
  • Patent number: 10605873
    Abstract: An apparatus for monitoring a magnetic core, wherein the apparatus provides a measurement winding which is magnetically coupled to the magnetic core to be monitored, a comparison inductance which is electrically connected in series with the winding and an electronic processing unit which is designed to determine the saturation behavior of the magnetic core to be monitored. The electronic processing unit is configured to record a first electrical signal occurring at the measurement winding and a second electrical signal occurring at the comparison inductance in response to an electrical measurement signal applied to the measurement winding, and to determine the saturation behavior of the magnetic core to be monitored on the basis of the first and second electrical signals. This makes it possible to easily monitor the saturation behavior of a magnetic core and to reliably detect the occurrence of saturation of the magnetic core.
    Type: Grant
    Filed: July 1, 2016
    Date of Patent: March 31, 2020
    Assignee: Sumida Components & Modules GMBH
    Inventor: Herbert Jungwirth
  • Patent number: 10234520
    Abstract: A carrier structure (2) of an arrangement (1) for modifying a main magnetic field generated in a magnetic resonance tomograph from multiple carrier elements (3, 37). A conductor arrangement (4) is respectively arranged on each carrier element (3, 37). The conductor arrangements (4) respectively include a primary conductor arrangement (6) for generating a primary magnetic field that modifies the main magnetic field and a secondary conductor arrangement (7) for shielding the primary magnetic field. A method for producing a modularly constructible arrangement (1) is provided, which can be used for example for spatial encoding.
    Type: Grant
    Filed: May 12, 2016
    Date of Patent: March 19, 2019
    Assignee: Albert-Ludwigs-Universität Freiburg
    Inventors: Sebastian Littin, Feng Jia, Maxim Zaitsev
  • Patent number: 10031046
    Abstract: A method for detecting defects in a piston for an internal combustion engine may include providing the piston in a measurement arrangement that includes a measurement probe having a first electrical coil element for generating an electromagnetic alternating field and a second electrical coil element for detecting an electromagnetic alternating field. The method may also include moving the measurement probe over a piston surface of the piston, and providing an electrical alternating current in the first coil element to generate an electromagnetic alternating field that interacts with a material of the piston in the region under the piston surface. The method may further include evaluating an electrical alternating voltage induced in the second coil element by the electromagnetic alternating field after interaction with the material of the piston.
    Type: Grant
    Filed: February 19, 2016
    Date of Patent: July 24, 2018
    Assignee: Mahle International GmbH
    Inventors: Michel Fritz, Gerhard Mook, Ioannis Papadopoulos, Holger Schnell
  • Patent number: 9853449
    Abstract: The present invention provides a system and computer program product for implementing a smart transformer, comprising a processor, and a balancing algorithm residing on the processor, wherein the balancing algorithm is stored on a non-transitory computer readable medium having computer executable program code embodied thereon, the computer executable program code configured to cause the system to monitor and control an electric customer load and generation in order to optimize the performance of a distribution transformer, wherein the processor receives a plurality of system inputs and uses the balancing algorithm to determine a rating of the transformer and an amount of customer load.
    Type: Grant
    Filed: March 20, 2015
    Date of Patent: December 26, 2017
    Inventors: William Vincent Torre, Amanda Louise Myers, Michael James Colburn
  • Patent number: 9625496
    Abstract: A magnetic sensor includes a magnetic detection element, and a correcting section to correct an output voltage of the magnetic detection element and output the corrected output voltage. The correcting section is configured to compute a magnetic flux density from the output voltage of the magnetic detection element, compute and output the corrected output voltage having a linear relationship to the computed magnetic flux density.
    Type: Grant
    Filed: April 9, 2015
    Date of Patent: April 18, 2017
    Assignee: HITACHI METALS, LTD.
    Inventors: Naoki Futakuchi, Yukio Ikeda, Kazuhisa Takahashi
  • Patent number: 9354123
    Abstract: In an embodiment, a circuit is configured to produce a magnetic field signal having a frequency spectrum. The circuit may also produce a temperature signal. A modulation circuit may modulate the temperature signal with a frequency outside the frequency spectrum of the magnetic field signal. The modulated signal and the magnetic field signal may be combined to produce a combined signal. A separation circuit may be configured to separate component signals from the combined signal. The separation circuit may include a first filter, which, when applied to the combined signal, produces a filtered signal; a modulation circuit configured to shift the data representing the temperature signal to a baseband frequency; and a second filter configured to separate the data representing the temperature signal from the combined signal.
    Type: Grant
    Filed: December 26, 2012
    Date of Patent: May 31, 2016
    Assignee: Allegro Microsystems, LLC
    Inventors: Mathew Drouin, Devon Fernandez, William P. Taylor
  • Patent number: 9354285
    Abstract: A magnetic measurement device which measures coercivity and coercivity distribution in a microregion of a thin plate magnetic sample with high coercivity. A magnetic sample is applied with a magnetic field in a first direction and magnetized, a second magnetic field is applied in a direction opposite to the first, a measuring part scans the sample, measuring magnetic flux leakage due to remnant magnetization in the sample. The intensity of the second magnetic field is gradually increased while the measuring part repeats the measurement to obtain the second magnetic field wherein the magnitude of the leakage from the sample reaches the maximum level, and when a magnetic field equivalent to the coercivity is applied to the sample and about half of the magnetization is reversed, the sample's coercivity is obtained based on the determination that the demagnetizing field Hd reaches the minimum level and the leakage reaches the maximum level.
    Type: Grant
    Filed: December 13, 2012
    Date of Patent: May 31, 2016
    Assignee: TDK CORPORATION
    Inventors: Kenichi Suzuki, Tsutomu Chikamatsu, Akio Ogawa, Kyung-ku Choi, Ryuji Hashimoto
  • Publication number: 20150077099
    Abstract: A structure for measuring iron loss of a motor stator core is provided. The structure includes an auxiliary core whose both end surfaces in a longitudinal direction come in contact with inner end surfaces of two adjacent stator teeth among a plurality of stator teeth in a radial direction in order to measure iron loss of a stator core in which a plurality of slots and the plurality of stator teeth are alternately formed on an inner circumferential surface of a stator yoke in a circumferential direction. A pair of excitation windings is provided at portions of the auxiliary core in the longitudinal direction spaced-apart from each other. A B-coil that is a sensor coil is provided at the auxiliary core so as to be positioned inside any one excitation winding of the pair of excitation windings.
    Type: Application
    Filed: July 22, 2014
    Publication date: March 19, 2015
    Inventors: Young Jin SEO, Myeong Kyu JUNG, Dongyeon HAN, Shin Gyu KIM, Chang-Seop KOH, Kwang-Young JEONG, Chan-Hyuk PARK, Hee-Sung YOON
  • Patent number: 8981018
    Abstract: The condition of internal or hidden material layers or interfaces is monitored and used for control of a process that changes a condition of a material system. The material system has multiple component materials, such as layers or embedded constituents, or can be represented with multiple layers to model spatial distributions in the material properties. The material condition changes as a result of a process performed on the material, such as by cold working, or from functional operation. Sensors placed proximate to the test material surface or embedded between material layers are used to monitor a material property using magnetic, electric, or thermal interrogation fields. The sensor responses are converted into states of the material condition, such as temperature or residual stress, typically with a precomputed database of sensor responses.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: March 17, 2015
    Assignee: Jentek Sensors, Inc.
    Inventors: Neil J. Goldfine, Vladimir A. Zilberstein, Ian C. Shay, Christopher A. Craven, David C. Grundy, Volker Weiss, Andrew P. Washabaugh
  • Publication number: 20140292316
    Abstract: An apparatus and method for detecting defects in a metal surface is disclosed. The apparatus is configured to move an eddy coil relative to an underlying metallic surface along a plurality of generally parallel and adjacent scan paths, and to receive from the eddy coil an oscillating signal induced at said coil as it is moved along each path. A representation of the received oscillating signal in relation to each one of a plurality of adjacent scan areas within each path is recorded, and a two-dimensional grid-like map showing the signal representations relative to each scan area is displayed. Defect location is facilitated by a further function of the apparatus and method, by which user input to an interface causes a light source to illuminate a selected part of the metallic surface.
    Type: Application
    Filed: June 12, 2012
    Publication date: October 2, 2014
    Applicant: SARCLAD LIMITED
    Inventor: Robert Northern
  • Patent number: 8847580
    Abstract: An apparatus and method of a tamperproof magnetic proximity sensor based on a magnetically shielded magnetic sensor. The proximity sensor is substantially impervious to external magnetic field and is protected by external magnetic sensors for preemptive detection of external magnetic field tamper attempts.
    Type: Grant
    Filed: March 7, 2011
    Date of Patent: September 30, 2014
    Inventor: Josef Osterweil
  • Publication number: 20140266169
    Abstract: A non-destructive test method for evaluating a synthetic rope made of strength member elements includes: treating at least one strength member element to be detectable by a magnetic NDT device, incorporating the at least one treated strength member element into the rope, scanning the synthetic rope with the magnetic NDT device, and obtaining magnetic flux leakage or eddy current output data from the magnetic NDT device, wherein the output data relates to a condition of the synthetic rope. A synthetic rope or cable is thereby made to be capable of being inspected by a magnetic flux leakage or eddy current non-destructive test (NDT) method.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: WHITEHILL MANUFACTURING CORPORATION
    Inventors: Elizabeth W. HUNTLEY, Mark B. HUNTLEY, A. Simeon WHITEHILL
  • Patent number: 8823370
    Abstract: Core loss in an inductor is measured with reduced sensitivity to phase measurement error by connecting a reactive component to resonate with the inductor and thus cancel a portion of the reactive voltage on the inductor; reducing the phase difference between the inductor voltage and current and making the observed power more resistive. The reactive component may be a capacitor for sinusoidal excitation or an inductance such as an air core transformer for arbitrary excitation.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: September 2, 2014
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Mingkai Mu, Fred C. Lee
  • Publication number: 20140225601
    Abstract: A device for measuring a magnetic field in an air-gap between a stator and a rotor of an electric machine includes a probe to detect the magnetic field and generate a signal indicative thereof and a display unit for the signal. The probe includes a plurality of sensors.
    Type: Application
    Filed: December 20, 2013
    Publication date: August 14, 2014
    Applicant: ALSTOM Technology Ltd
    Inventors: Maximilian HOBELSBERGER, Simon Christoph HONOLD, Roland Richard MOSER
  • Patent number: 8803515
    Abstract: A substantially planar eddy-current sensor having durability enhancing pillars in an active region is provided. The pillars are distributed and sized so as to have limited effect on the sensor's performance. When the sensor is mounted on a component such that the sensor experiences forces on a top and bottom surface, the pillars bear the load reducing the load bore by the active elements (e.g., drive winding, sense elements). A sensor with redundant drive windings and/or redundant sense elements is disclosed. The redundant elements may be connected to separate electronics. Another aspect relates to providing a reference transformer for calibration of a sensor. The secondary windings of the reference transformer are connected in series with the sense elements of the sensor to be calibrated. Transimpedance measurements are made when the drive winding of the reference transformer is excited. The measurements are used to correct transimpedance measurements made when the drive winding of the sensor is excited.
    Type: Grant
    Filed: February 9, 2011
    Date of Patent: August 12, 2014
    Assignee: JENTEK Sensors, Inc.
    Inventors: Neil J. Goldfine, David C. Grundy, Darrell E. Schlicker, Andrew P. Washabaugh
  • Patent number: 8744781
    Abstract: A method for determining tube support plate blockage of a steam generator includes the following steps: measuring at least five different eddy current values per tube support intersection; calculating a nominal clean fit radius of flow hole; determining a center signal response; converting the center signal response to a deposit thickness; determine an edge reduction; converting the edge reduction to an edge thickness; calculating the resulting flow hole radius; verifying the reasonableness of the resulting flow hole radius; and determining a virtual calibration range.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: June 3, 2014
    Assignee: AREVA Inc.
    Inventors: John C. Griffith, Joseph R. Wyatt, Mihai G. M. Pop, Jeffrey M. Fleck
  • Patent number: 8742752
    Abstract: A method of eddy current testing for flaws in a tube is provided that includes passing an eddy current probe through the tube and obtaining eddy current data for a number of positions along the tube, analyzing the eddy current data to generate background noise data for a number of positions along the tube, analyzing the eddy current data to generate extracted data for a number of positions along the tube, and determining whether a flaw of a particular category is present in the tube based on a set of one or more of rules applied to at least a portion of the extracted data, wherein at least one of the rules uses a particular part of the extracted data and employs a threshold that is a function a particular part of the background noise data that is associated with the particular part of the extracted data.
    Type: Grant
    Filed: October 1, 2010
    Date of Patent: June 3, 2014
    Assignee: Westinghouse Electric Company LLC
    Inventors: Qui V. Lee, G. Craig Bowser
  • Patent number: 8717012
    Abstract: An eddy current probe includes an excitation coil for coupling to a low-frequency alternating current (AC) source. A magnetoresistive sensor is centrally disposed within and at one end of the excitation coil to thereby define a sensing end of the probe. A tubular flux-focusing lens is disposed between the excitation coil and the magnetoresistive sensor. An excitation wire is spaced apart from the magnetoresistive sensor in a plane that is perpendicular to the sensor's axis of sensitivity and such that, when the sensing end of the eddy current probe is positioned adjacent to the surface of a structure, the excitation wire is disposed between the magnetoresistive sensor and the surface of the structure. The excitation wire is coupled to a high-frequency AC source. The excitation coil and flux-focusing lens can be omitted when only surface inspection is required.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: May 6, 2014
    Assignee: The United States of America as respresented by the United States National Aeronautics and Space Administration
    Inventors: Russell A. Wincheski, John W. Simpson
  • Patent number: 8699654
    Abstract: The invention concerns a method comprising measurement on a fuel channel (14) of fuel assemblies (8) for nuclear boiling water reactors. The method comprises that: the measurement is done by the use of a non-destructive inductive eddy current measurement method, the measurement is done on a fuel channel (14) which has been used at least a certain time during operation in the core of a nuclear boiling water reactor, the measurement is done when the fuel channel (14) is located in water, the measurement is done on different places on the fuel channel (14), wherein through the method at least the hydride content of the fuel channel (14) at said places is determined. The method can be used in order to find out how shadow corrosion from a neighboring control rod influences the properties of the fuel channel (14).
    Type: Grant
    Filed: June 8, 2009
    Date of Patent: April 15, 2014
    Assignee: Westinghouse Electric Sweden AB
    Inventors: Kurt-Åke Magnusson, Holger Wiese, Björn Andersson, Göran Jergeus
  • Patent number: 8618794
    Abstract: A system for detecting inductive objects includes an inductive sensor circuit for detecting changes in an electromagnetic field (“EMF”) environment and an integrated circuit (“IC”) device. The inductive sensor circuit generates an oscillating analog waveform with an envelope that indicates changes in the EMF environment. The oscillating waveform is coupled to the digital input pin of the IC. A digital interface circuit in the IC is coupled to the digital input pin and is configured for detecting if the oscillating waveform exceeds high and low threshold voltage levels. The detecting results in a digital pulse which represents changes in the EMF environment. In another implementation, a timer input capture pin can be used to detect the waveform envelope decay by storing the time when the waveform crosses a threshold value during a time period. A reduced capture time after the time period expires indicates a change in the EMF environment.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: December 31, 2013
    Assignee: Atmel Corporation
    Inventors: Jonas Ask, Ivar Holand
  • Patent number: 8527216
    Abstract: A method for determining tube support plate blockage of a steam generator includes the following steps: measuring at least five different eddy current values per tube support intersection; calculating a nominal clean fit radius of flow hole; determining a center signal response; converting the center signal response to a deposit thickness; determine an edge reduction; converting the edge reduction to an edge thickness; calculating the resulting flow hole radius; verifying the reasonableness of the resulting flow hole radius; and determining a virtual calibration range.
    Type: Grant
    Filed: February 8, 2010
    Date of Patent: September 3, 2013
    Assignee: Areva NP Inc
    Inventors: John C. Griffith, Joseph R. Wyatt, Mihai G. M. Pop, Jeffrey M. Fleck
  • Publication number: 20130214769
    Abstract: A method for non-destructively characterizing one or more regions within a polycrystalline structure using capacitance and eddy current measurements. The eddy current measurements include at least one of an impedance amplitude and a phase shift angle. The capacitance is measured one or more times and compared to a first calibration curve to determine an estimated leaching depth within the polycrystalline structure. A first data scattering range is ascertained from the capacitance measurements to determine a relative porosity or the leaching quality within the polycrystalline structure. The eddy current is measured one or more times and compared to a second calibration curve to determine an estimated leaching depth within the polycrystalline structure. A second data scattering range is ascertained from the eddy current measurements to determine a relative porosity or the leaching quality within the polycrystalline structure.
    Type: Application
    Filed: February 21, 2012
    Publication date: August 22, 2013
    Applicant: Varel International Ind., L.P.
    Inventors: William W. King, Federico Bellin, Vamsee Chintamaneni
  • Publication number: 20130214768
    Abstract: A method, system, and apparatus for non-destructively characterizing one or more regions within an ultra-hard polycrystalline structure using eddy current measurements. The apparatus includes an eddy current measuring device having at least one terminal, a leached component comprising a polycrystalline structure, a first wire, and a probe. The leached component includes a cutting surface and an opposing second surface. A portion of the polycrystalline structure extending inwardly from the cutting surface has at least a portion of a catalyst material removed from therein. The first wire electrically couples the terminal to the probe, which is placed in contact with the cutting surface. The eddy current is measured one or more times and compared to a calibration curve to determine an estimated leaching depth within the polycrystalline structure. A data scattering range is ascertained to determine a relative porosity of the polycrystalline structure or the leaching quality within the polycrystalline structure.
    Type: Application
    Filed: February 21, 2012
    Publication date: August 22, 2013
    Applicant: Varel International Ind., L.P.
    Inventors: Vamsee Chintamaneni, Federico Bellin
  • Publication number: 20130169271
    Abstract: An MTJ sensor having low hysteresis and high sensitivity is disclosed. The MTJ sensor includes, in one embodiment, a bridge with first and second active MTJ elements and first and second passive MTJ elements connected in a Wheatstone bridge configuration. First and second magnetic shield elements are located over the first and second passive MTJ elements and form a gap therebetween that concentrates magnetic flux toward the first and second active MTJ elements. A three-dimensional coil is wound around the first and second magnetic shield elements with over-windings located over the first and second magnetic shield elements and under-windings located under the first and second magnetic shield elements, connected together by a plurality of vias adjacent the first and second magnetic shield elements.
    Type: Application
    Filed: December 30, 2011
    Publication date: July 4, 2013
    Applicant: NVE CORPORATION
    Inventors: Catherine Ann Nordman, Peter Eames, Russ Beech, David J. Brownell
  • Patent number: 8473235
    Abstract: The present invention provides apparatus for scanning a product to detect metal in that product. The apparatus comprises a drive coil (4), for generating an electromagnetic field in the product, and a detection coil arranged to detect fluctuations in the magnetic field caused by the presence of a metallic particle in the product. A drive circuit (26) for the drive coil (4) comprises a plurality of switches (19 to 22) driven by a controller (16), which switch alternately connect the drive coil across a potential difference to cause the drive coil to be driven at an operating frequency determined by operation of the switches. Using a switching circuit to drive the drive coil (4) greatly increases the number of frequencies at which the drive coil may be operated. The invention has particular application to the food industry.
    Type: Grant
    Filed: January 9, 2006
    Date of Patent: June 25, 2013
    Assignee: Illinois Tool Works Inc.
    Inventors: Clive Francis Kittel, Paul Jeffrey King
  • Patent number: 8436608
    Abstract: A multi-frequency eddy current (MFEC) inspection system is provided for inspection of case hardening depth on a part. The MFEC inspection system comprises a generator configured to generate one or more multi-frequency excitation signals and an eddy current probe configured to be disposed at one side of the part. The eddy current probe comprises one or more drivers and one or more pickup sensors. The one or more drivers are configured to receive the one or more multi-frequency excitation signals to induce eddy currents in the part. The one or more pickup sensors are configured to detect the induced eddy currents within a local area of the part to generate one or more multi-frequency response signals. The MFEC system further comprises a processor configured to receive the one or more multi-frequency response signals for processing to determine a case hardening depth of the local area of the part. A pulse eddy current inspection system and an eddy current inspection method are also presented.
    Type: Grant
    Filed: September 21, 2009
    Date of Patent: May 7, 2013
    Assignee: General Electric Company
    Inventors: Haiyan Sun, Yuri Alexeyevich Plotnikov, Changting Wang, Shridhar Champaknath Nath, Aparna Chakrapani Sheila-Vadde
  • Publication number: 20130049744
    Abstract: Core loss in an inductor is measured with reduced sensitivity to phase measurement error by connecting a reactive component to resonate with the inductor and thus cancel a portion of the reactive voltage on the inductor; reducing the phase difference between the inductor voltage and current and making the observed power more resistive. The reactive component may be a capacitor for sinusoidal excitation or an inductance such as an air core transformer for arbitrary excitation.
    Type: Application
    Filed: August 31, 2011
    Publication date: February 28, 2013
    Inventors: Mingkai Mu, Fred C. Lee
  • Patent number: 8376622
    Abstract: The invention relates to a device for detecting and monitoring damage to races or adjacent regions of bearing rings (1, 2, 3) of anti-friction bearings. The device includes a measuring device, disposed in the anti-friction bearing chamber, having a sensor and structure for supplying sensor measurement data to the outside. The device has an energy source, which is also disposed in the anti-friction roller bearing chamber and which comprises a first coil (16) for the measuring device and a second coil (18) disposed outside the anti-friction bearing chamber and destined for inductive transfer of electrical energy to the first coil (16). The second coil (18) extends only over a part of the bearing circumference and the energy source comprises an energy accumulator (19) connected to the first coil (16).
    Type: Grant
    Filed: April 2, 2008
    Date of Patent: February 19, 2013
    Assignee: Rothe Erde GmbH
    Inventors: Wolfgang Claus, Wolfgang Werther
  • Patent number: 8358125
    Abstract: In a method for determining geometrical characteristics (d) of an anomaly (12) which changes the electrical conductivity in the region near the surface of an electrically conducting, in particular a metallic test object (10), a considerable simplification is achieved in that, in the region of the anomaly (12) in the test object (10), eddy currents (13, 14) of different frequencies are excited, and the magnetic field (By,0), which is produced by the excited eddy currents, is scanned in the vicinity of the anomaly (12) and the geometric characteristics of the anomaly are exclusively deduced from the distribution of the magnetic field (By,0).
    Type: Grant
    Filed: October 29, 2008
    Date of Patent: January 22, 2013
    Assignee: ALSTOM Technology Ltd.
    Inventors: Roland Richard Moser, Bernard Revaz, Serge Reymond, Pavel Kejik, Radivoje Popovic
  • Patent number: 8358126
    Abstract: A method of testing for defects in the bottom of an above ground storage tank, the tank bottom having a lip extending outwardly from the tank wall around the circumference of the tank. A special magnetostrictive sensor is designed to be placed on this lip. The sensor is placed over a strip of magnetostrictive material, which generally conforms in length and width to the bottom of the probe, with a couplant being applied between the strip and the lip surface. The sensor is then operated in pulse echo mode to receive signals from defects in the bottom of the tank. It is incrementally moved around the circumference of the tank.
    Type: Grant
    Filed: January 14, 2010
    Date of Patent: January 22, 2013
    Assignee: Southwest Research Institute
    Inventors: Glenn M Light, Alan R Puchot, Adam C Cobb, Erika C Laiche
  • Publication number: 20130009632
    Abstract: An eddy current measuring probe sensor has an exciting portion and a detecting portion. The exciting portion includes a primary exciting portion that includes a main core formed of a cylindrical magnetic body and a main coil that is a solenoid coil wound in a circumferential direction around the main core, and a plurality of secondary exciting portions that include sub-cores formed of cylindrical magnetic bodies that are arranged around the primary exciting portion in a manner such that an axial direction of each of the sub-cores is the same as an axial direction of the main core.
    Type: Application
    Filed: December 21, 2010
    Publication date: January 10, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Takanari Yamamoto
  • Patent number: 8274282
    Abstract: The invention concerns a method for producing an assembly of at least one transmission coil (B1) and one reception coil (B2) for eddy current testing, the reception coil receiving in the absence of fault a complex amplitude signal VR, subject to a variation ?VR in the presence of a characteristic fault to be detected. The method consists in selecting the distance ?ER between the axes of the transmission coil and the reception coil so as to maximize the ratio I?VR/VRI.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: September 25, 2012
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Jean-Marc Decitre, Thierry Sollier
  • Patent number: 8232797
    Abstract: A device with separate emission/reception functions for making eddy current tests on an electrically conducting part comprising several emission rows (1-4) composed of emission windings (55), and several reception columns (a-h) each composed of reception windings (56) connected in series in at least one series, in which the emission windings associated with the reception windings in one series are powered by currents at different frequencies.
    Type: Grant
    Filed: July 30, 2007
    Date of Patent: July 31, 2012
    Assignee: Commissariat a l'Energie Atomique
    Inventor: Jean-Marc Decitre
  • Patent number: 8228058
    Abstract: Disclosed is an eddy current flaw detection probe that is capable of pressing itself against an inspection target whose curvature varies. A flaw sensor is configured by fastening a plurality of coils to a flexible substrate that faces the surface of the inspection target. A first elastic body is positioned opposite the inspection target for the flaw sensor, is obtained by stacking two or more elastic plates, and has an elastic coefficient that varies in a longitudinal direction. A second elastic body is a porous body positioned between the flexible substrate and the first elastic body. A pressure section is employed to press the first elastic body toward the inspection target.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: July 24, 2012
    Assignee: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Akira Nishimizu, Hirofumi Ouchi, Yoshio Nonaka, Yosuke Takatori, Akihiro Taki, Makoto Senoo
  • Patent number: 8222896
    Abstract: On a friction stir spot welded workpiece having a first side including a friction stir spot weld hole and an opposing smooth second side, an eddy current probe is passed over the spot weld hole from the second side, and an eddy current signal representative of a material thickness of the workpiece is produced. The eddy current is analyzed via an eddy current analyzer, and a graphic representation of the analyzed eddy current signal is monitored as the probe passes over the spot weld hole, and a local minima of the graphic representation defined by a displayed characteristic J-shaped curve is identified, the local minima defining a remaining material thickness of the workpiece at the bottom of the spot weld hole. From the graphic representation, a value of the remaining material thickness is determined, and a weld strength of the spot weld as a function of the remaining material thickness is determined.
    Type: Grant
    Filed: October 12, 2009
    Date of Patent: July 17, 2012
    Assignee: GM Global Technology Operations
    Inventor: Cameron John Dasch
  • Patent number: 8212553
    Abstract: An eddy current probe testing apparatus structured to operate concurrently in a driver pick-up mode and said impedance mode is provided. The eddy current probe has two coils. The eddy current probe testing apparatus also includes a signal producing device, an output device, and a switch assembly. The switch assembly is structured to switch how an input signal from the signal producing device is provided to the two coils.
    Type: Grant
    Filed: December 21, 2009
    Date of Patent: July 3, 2012
    Assignee: Westinghouse Electric Company LLC
    Inventors: Thomas W. Nenno, Warren R. Junker, Richard M. Novotny, Conrad S. Wyffels
  • Patent number: 8203336
    Abstract: An eddy current probe uses magnetic gap. The probe has a small size; and coil number in the probe is reduced. Hence, the probe can move easily inside and outside a tube and detect an end of the tube as close as possible.
    Type: Grant
    Filed: September 13, 2009
    Date of Patent: June 19, 2012
    Assignee: Atomic Energy Council Institute of Nuclear Energy Research
    Inventors: Kang-Neng Peng, Ching-Shih Liu, Kang-Lin Hwang
  • Patent number: 8164328
    Abstract: An eddy current system and method enables detection of sub-surface damage in a cylindrical object. The invention incorporates a dual frequency, orthogonally wound eddy current probe mounted on a stepper motor-controlled scanning system. The system is designed to inspect for outer surface damage from the interior of the cylindrical object.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: April 24, 2012
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Russell A. Wincheski, John W. Simpson
  • Patent number: 8138755
    Abstract: An enhanced wireless eddy current probe is disclosed which has means to wirelessly couple to a non-destructive inspection (NDI) system situated some distance away from an inspection point on a material under inspection. The disclosed enhanced wireless eddy current probe provides means for executing advanced functions necessary for a complex eddy current inspection operation. These functions include, but are not limited to, storing, loading, and executing a predetermined firing sequence on an array of coil elements, probe balancing, probe calibration, and providing bibliographic information specific to said probe to a wirelessly coupled NDI system.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: March 20, 2012
    Assignee: Olympus NDT
    Inventor: Michael Drummy
  • Publication number: 20120025813
    Abstract: An system for detecting inductive objects includes an inductive sensor circuit for detecting changes in an electromagnetic field (“EMF”) environment and an integrated circuit (“IC”) device. The inductive sensor circuit generates an oscillating analog waveform with an envelope that indicates changes in the EMF environment. The oscillating waveform is coupled to the digital input pin of the IC. A digital interface circuit in the IC is coupled to the digital input pin and is configured for detecting if the oscillating waveform exceeds high and low threshold voltage levels. The detecting results in a digital pulse which represents changes in the EMF environment. In another implementation, a timer input capture pin can be used to detect the waveform envelope decay by storing the time when the waveform crosses a threshold value during a time period. A reduced capture time after the time period expires indicates a change in the EMF environment.
    Type: Application
    Filed: July 30, 2010
    Publication date: February 2, 2012
    Applicant: ATMEL CORPORATION
    Inventors: Jonas Ask, Ivar Holand
  • Patent number: 8089274
    Abstract: The present invention relates to a method for evaluating the SOI wafer in a method for evaluating an SOI wafer in which a sheet resistance of a buried diffusion layer of an SOI wafer that has at least an SOI layer on an insulator layer and has a buried diffusion layer whose impurity concentration is higher than other region of the SOI layer in an interface area with the insulator layer of the SOI layer is evaluated, the method including the steps of measuring a sheet resistance of the whole SOI layer or the whole SOI wafer, and estimating the sheet resistance of the buried diffusion layer by assuming respective layers that compose the SOI wafer to be resistors connected in parallel and converting the measured result of the sheet resistance measurement. As a result of this, there is provided a method for evaluating the SOI wafer that can directly measure the SOI wafer itself to be the product to thereby evaluate the sheet resistance of the buried diffusion layer thereof, without fabricating a monitor wafer.
    Type: Grant
    Filed: May 10, 2007
    Date of Patent: January 3, 2012
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventor: Kazuhiko Yoshida
  • Patent number: 8054593
    Abstract: A circuit that includes a single grounded fault sensing transformer coupled to a resonant circuit that produces an output signal used by a microcontroller to determine a load current flowing through at least two conductors passing through the center of the sensing transformer. The microcontroller pings the resonant circuit, causing an impulse disturbance at the output signal, and the microcontroller calculates the inductance component of the resonant circuit based on the frequency of the decaying output signal. The microcontroller calculates the resistive core loss as a function of a known resistance of the resonant circuit, a known capacitance of the resonant circuit, the calculated inductance, and the determined rate of decay of the output signal. The calculated resistive core loss is compared to a table or to a polynomial function that characterizes known resistive core losses with known load currents to determine the load current corresponding to the calculated resistive core loss.
    Type: Grant
    Filed: December 29, 2008
    Date of Patent: November 8, 2011
    Inventors: Paul A. Reid, Robert Erger
  • Patent number: 8049494
    Abstract: A flexible array probe is disclosed suitable for use in the non-destructive testing and inspection of test pieces with varying cross-sectional geometries. Array elements—such as, but not limited to, eddy current sensors, piezoelectric sensor elements, and magnetic flux leakage sensors—are mounted on thin alignment fins and coupled together with pairs of pivot mechanisms along the axis of desired rotation. The pivot mechanisms allow rotation in exactly one dimension and force the flexible array probe to align its elements orthogonally to the surface of the structure under test. Alignment and coupling fixtures are also disclosed.
    Type: Grant
    Filed: May 20, 2008
    Date of Patent: November 1, 2011
    Assignee: Olympus NDT
    Inventors: Benoit Lepage, Martin Roy, Stefano Orsi
  • Patent number: 8000936
    Abstract: A data analysis program operable for displaying at least one representation of a buried pipeline in a geographical area and associated on-pipe current values at various locations along the pipeline. The data analysis program is storable in a memory device and executable by a processor to generate a display on a display device. The data analysis program includes instructions for displaying a digital map representing at least a portion of the buried pipeline extending across the geographical area being surveyed. The program further includes instructions for displaying a current plot of current values associated with the various locations in the geographical area, and instructions for displaying a table having a plurality of fields including the leakage current values and associated geographical coordinates where the current values were measured in the geographical area being surveyed.
    Type: Grant
    Filed: November 10, 2008
    Date of Patent: August 16, 2011
    Assignee: Saudi Arabian Oil Company
    Inventor: Thomas James Davis
  • Publication number: 20110133729
    Abstract: A method and a monitoring device for performing an RF-safe MIT scan is disclosed in which it is prevented that an RF exposure, especially a specific absorption rate (SAR), imposed on an examination object, especially a patient, exceeds certain limit values during a magnetic induction tomography (MIT) scan. This is achieved on the one hand by an RF simulation method for simulating intended MIT operating parameters and calculating a resulting RF exposure of the object, and on the other hand by a monitoring device for monitoring the RF power which is applied to the object.
    Type: Application
    Filed: August 7, 2009
    Publication date: June 9, 2011
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Peter Vernickel, Peter Mazurkewitz, Daniel Wirtz, Christoph Leussler, Ulrich Katscher