With Phase Sensitive Element Patents (Class 324/233)
  • Patent number: 10634655
    Abstract: Disclosed herein are a method for analyzing heavy metal removal efficiency using phase difference analysis and an apparatus using the method. The method for analyzing heavy metal removal efficiency using phase difference analysis includes applying a magnetic field to a magnetite onto which a heavy metal is adsorbed, based on a first solenoid coil and a second solenoid coil that have an identical winding direction, applying a high-frequency signal to the magnetite, based on a third solenoid coil having a winding direction that differs from that of the first solenoid coil and the second solenoid coil, detecting a high-frequency signal transformed by the magnetite, and calculating a phase difference between a previously detected default high-frequency signal and the transformed high-frequency signal, and analyzing an efficiency of heavy metal removal by the magnetite by measuring a concentration of the heavy metal based on the phase difference.
    Type: Grant
    Filed: May 18, 2017
    Date of Patent: April 28, 2020
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Hyo-Bong Hong, Jae-Chan Jeong, Seung-Min Choi, Sung-Woong Shin, Jae-Il Cho, Nam-Shik Park
  • Patent number: 10191012
    Abstract: A method for monitoring local defects in a rotating engine component such as a gear uses one or more eddy current sensor(s) arranged to interact with the engine component as it is rotating during service. The eddy current sensor(s) may be carried by one or more teeth of a monitoring gear. A device is arranged to measure an output signal from the eddy current sensor(s) resulting from interaction with the rotating engine component. The output signal is processed so as to detect a change in shape of the output signal indicative of a local defect.
    Type: Grant
    Filed: January 9, 2013
    Date of Patent: January 29, 2019
    Assignee: Oxford University Innovation Limited
    Inventor: Kamaljit Singh Chana
  • Patent number: 10180512
    Abstract: The present disclosure provides a current monitoring circuit for monitoring current in a geophysical survey system. The circuit may be utilized in dipole-dipole systems including one or more electrode stations or in loop systems. The circuit includes a transmitter configured to generate an output current. One or more current monitors are positioned to detect current at or near the electrode stations or at positions along the one or more loops. Measured current data is transmitted back to the transmitter, which may be shut down if necessary. Methods for monitoring current in a geophysical survey system are also provided.
    Type: Grant
    Filed: April 6, 2016
    Date of Patent: January 15, 2019
    Assignee: ZONGE INTERNATIONAL, INC.
    Inventors: David Baum, Scott A. Urquhart, Scott C. MacInnis
  • Patent number: 10031107
    Abstract: A method for the non-destructive testing of a test component made of an electrically conductive material is described. The method employs movably mounted permanent magnets, which provides a means for generating a variable DC magnetic field within the test component, and eddy current probes to provide a means for performing a partial saturation eddy current test upon the test component. The eddy current probe preferably comprises an integrated magnetic field sensor which increases the accuracy and flexibility of the modes of operation of the described methods. The described methods are particularly suited for the inspection of tubular components that are often remotely located within the oil and gas exploration and production industries.
    Type: Grant
    Filed: February 3, 2016
    Date of Patent: July 24, 2018
    Assignee: Innospection Group Limited
    Inventor: Andreas Boenisch
  • Patent number: 9836682
    Abstract: A system for detecting the depth of an antenna embedded in the card body of a smart card includes a milling device for forming a cavity in the card body, a test device disposed in close proximity to the card body, a vector network analyzer (VNA) for measuring a linear characteristic of the test device, and a control device for regulating operation of the milling device in view of data collected by the VNA. In use, the VNA generates a test signal and measures the degree of signal reflection from the test device. Under normal conditions, the VNA observes a spike in forward return loss at the natural resonant frequency of the open antenna circuit. However, at the instant that the milling device contacts the antenna, a notable variance in the degree of signal reflection is observed which indicates that the proper antenna depth has been reached.
    Type: Grant
    Filed: April 7, 2015
    Date of Patent: December 5, 2017
    Assignee: AMERICAN BANKNOTE CORPORATION
    Inventor: Thomas Ziemkus
  • Patent number: 9696280
    Abstract: This invention concerns a device and a method for inspecting aluminum cables with a steel core (ASCRs), installed in energized electrical energy lines, which use the ECT (Eddy Current Testing) technique for evaluating the remaining thickness of the zinc layer which covers the steel wires of the cables inspected, where the readings of the tension of the detection solenoid and the current of the excitation solenoid are taken as the current of the conductor reaches zero, the electrical parameters of the conductor are corrected for the average temperature during the inspection and the signal from the detection solenoid is filtered through a hybrid circuit which is designed to increase the sensitivity of the measurement.
    Type: Grant
    Filed: July 10, 2015
    Date of Patent: July 4, 2017
    Assignees: Light Serviços de Electricidade S/A, Fundação CPQD—Centro de Pesquisa e Desenvovlvimento em Telecomunicações
    Inventors: Célio Fonseca Barbosa, Flávio Eduardo Nallin, Raphael Nunes de Souza
  • Patent number: 9612354
    Abstract: There are systems and methods for performing a geophysical survey using a hybrid aircraft which includes an apparatus configured to perform the geophysical survey. The system including: three mutually orthogonal transmitters configured to transmit electromagnetic (EM) waveforms towards the ground which creates a secondary magnetic field, wherein the three mutually orthogonal transmitters are attached to the hybrid aircraft; three mutually orthogonal null-coupled receivers configured to obtain measurements associated with the secondary magnetic field, wherein the three mutually orthogonal null-coupled receivers are attached to the hybrid aircraft; and three mutually orthogonal gradient receivers configured to obtain measurements, wherein the three mutually orthogonal gradient receivers are attached to the hybrid aircraft.
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: April 4, 2017
    Assignee: CGG SERVICES SAS
    Inventors: Richard Partner, Adam Smiarowski, Tom Payne, Stuart Stevenson, George Nader, Philip Miles
  • Patent number: 9523745
    Abstract: Provided are a magnetic sensor and a method of manufacturing the same capable of arranging a magnetic converging plate on a substrate on which Hall elements and a circuit are formed, with a small variation in position while suppressing an increase in number of work processes, the magnetic converging plate having high magnetic permeability and low coercive force. In the magnetic sensor and the method of manufacturing the same, in forming Hall elements and a circuit on a silicon substrate, a magnetic converging plate holder having a pattern recessed to have the same shape and size as those of a magnetic converging plate is formed, and, into the magnetic converging plate holder, the magnetic converging plate manufactured through processes different from those of the silicon substrate on which the Hall elements and the circuit are formed is inserted.
    Type: Grant
    Filed: February 10, 2016
    Date of Patent: December 20, 2016
    Assignee: SII Semiconductor Corporation
    Inventors: Takaaki Hioka, Mika Ebihara
  • Patent number: 9453817
    Abstract: In conventional non-destructive inspection devices using magnetism, the subject of inspection was limited to the surface layer of the test object as a result of the skin effect, and it was not possible to perform flaw detection inspection at the interior or reverse surface of thick-structured test objects. The effect of the surface effect was eliminated by imparting an external signal canceling the detection output of the test object surface layer from the detection output of a magnetic field resulting from eddy currents induced in the test object. As a result, it has become possible to extract the detection output of the test object interior that had been masked by the detection output of the test object surface layer, and it has become possible to perform thickness inspection and flaw detection of the reverse surface and interior or a test object.
    Type: Grant
    Filed: August 13, 2013
    Date of Patent: September 27, 2016
    Assignee: DAINICHI Machine and Engineering Co., Ltd.
    Inventors: Kunihiko Nakamura, Gijun Idei
  • Patent number: 9448323
    Abstract: A device and associated method for detecting metallic contaminants in a product using a signal received from a coil-based metal detector. A calibration module is configured to determine a product-specific, bowtie-shaped detection envelope based on calibration phase metal detector signals. A detection module is configured to compare, in a coordinate system for resistive and reactive components of a metal detector signal, a vector representation of the signal to the product-specific, bowtie-shaped detection envelope, and to indicate a presence of a metallic contaminant in the product when the vector representation of the signal extends to an area outside the bowtie-shaped detection envelope.
    Type: Grant
    Filed: June 14, 2013
    Date of Patent: September 20, 2016
    Assignee: METTLER-TOLEDO SAFELINE LTD.
    Inventor: Max Derungs
  • Patent number: 9350985
    Abstract: Disclosed is a method and an apparatus for removing circling drifts on the display of the measured eddy current or other continuous waves. The circling dot which is supposed to be a static dot can obscure information required by the operator to judge if a small defect is present. Embodiments of presently disclosed harmonic rejection filters are tunable and employed to effectively abate or eliminate signals with frequencies that are multiples of operating frequencies, resulting in the removal of the circling effects on the display.
    Type: Grant
    Filed: September 25, 2013
    Date of Patent: May 24, 2016
    Assignee: OLYMPUS NDT, INC.
    Inventor: Andrew Thomas
  • Patent number: 9297849
    Abstract: A wafer test system includes an input device configured to transmit a test signal, a wafer including an optical port, an input port configured to receive the test signal, and an output port configured to output a result signal based on the test signal, a measuring device configured to measure the result signal, and an alignment device configured to align an optical fiber port of an optical probe with an alignment port based on the result signal and then align the optical fiber port with the optical port. The alignment port is the input port or the output port. The optical probe is configured to be the input device when the input port is the alignment port and the optical probe is configured to be the measuring device when the output port is the alignment port.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: March 29, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Dong Jae Shin, Yoon Dong Park, Sang Hun Choi, Kyoung Ho Ha
  • Patent number: 9176597
    Abstract: A directional capacitive proximity sensor circuit capable of providing directional capacitive proximity sensing includes one or more guard electrodes, a first sensor, and a second sensor. The directional capacitive proximity sensor is installed in a device such that the first sensor is positioned near a first component of the device, and the second sensor is positioned near a second component of the device. The first and second sensors measure a capacitance to detect proximity of a user relative to the respective sensor, wherein the detected proximity is interpreted to determine a direction in which the user proximity is detected relative to the directional capacitive proximity sensor circuit. The guard electrode is provided to mitigate stray capacitance to reduce error in the capacitance measurements obtained by the first and second sensors.
    Type: Grant
    Filed: July 2, 2012
    Date of Patent: November 3, 2015
    Assignee: STMicroelectronics Asia Pacific Pte Ltd
    Inventors: Jenn Woei Soo, Kien Beng Tan
  • Patent number: 9128840
    Abstract: The apparatus and methods allow for correcting data from a sensor due to changes in relative speed of that sensor. The methods and apparatus described use a determined entropy from data associated with across a direction of travel of the sensor together with a determined entropy from data associated with in a direction of travel of the sensor. The determined entropies allow for providing for correcting the data for changes in the relative speed of the sensor. Also, described are methods and apparatus for correcting data from at least first and second sensors of a measurement device, whereby features are correlated from datasets taken from both sensors to determine one or more corresponding signatures. These signatures can then be used to correct the data from first and second sensors.
    Type: Grant
    Filed: September 26, 2011
    Date of Patent: September 8, 2015
    Assignee: Senergy Technology Limited
    Inventor: Jules May
  • Patent number: 8884613
    Abstract: A water-chamber working apparatus 1 according to the present invention includes a movable body that can move along a tube plate 12 of a steam generator 10, an extendable member 21 that extends and retracts in a direction in which a first coupling portion 21d approach each other and a direction in which these portions move away from each other, where the first coupling portion 21d is attached to a maintenance hatch 15 via a first joint 23a including two rotation axes intersecting with each other, and the second coupling portion 21e is attached to the movable body via a second joint 23b including two rotation axes intersecting with each other, which are different from the rotation axes of the first joint 23a.
    Type: Grant
    Filed: January 19, 2011
    Date of Patent: November 11, 2014
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventor: Jun Fujita
  • Patent number: 8773118
    Abstract: A magnetometer which includes an elongate reactor in which a sample can be secured in a sample support zone and which is located within a magnetic field space of a magnetic field generator and one or more signal pickup coils. Movement generating means is provided for generating relative movement in a generally linear direction between the reactor and at least one of the magnetic field and pickup coil, preferably by moving the reactor in its length. The magnetometer is characterised in that the reactor is a metal tube having a length which permits its ends to remain external of the signal pickup device during the relative movement.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: July 8, 2014
    Assignee: University of Cape Town
    Inventors: Michael Christian Maximilian Claeys, Eric Wilhelmus Josephus Van Steen, Jacobus Lucas Visagie, Jan van de Loosdrecht
  • Patent number: 8680851
    Abstract: A facility for generating a detection signal upon the presence of metallic-conductive parts in a conveyed flow that is at least largely non-conductive, in which, for example, an alternating electromagnetic field is established in a section of the conveyed flow to be monitored by means of an alternating current generator and a transmitter coil system, whereby a variation of the signal of said field that is triggered by passage of a part is detected by a receiver coil system and converted into a detection signal by an analytical circuit. The individual components of the system are distributed over separate circuit modules which in turn act in concert by means of a bus system.
    Type: Grant
    Filed: April 22, 2009
    Date of Patent: March 25, 2014
    Assignee: Mesutronic Gerätebau GmbH
    Inventor: Manfred Artinger
  • Patent number: 8674685
    Abstract: A magnetic flux position sensor includes a primary coil, a secondary coil, and a magnetic flux conductor. The primary coil generates a magnetic flux and the secondary coil senses magnetic flux. The primary and secondary coils are substantially concentric and spaced apart by an annular passage. The annular passage has first and second ends, and the magnetic flux conductor is slidable from the first end to the second end of the annular passage. The magnetic flux transferred from the primary coil to the secondary coil varies as a function of position of the magnetic flux conductor.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: March 18, 2014
    Assignee: Hamilton Sundstrand Corporation
    Inventor: Bruce Paradise
  • Patent number: 8593137
    Abstract: An eddy current sensor that includes: a probe and a computing unit. The probe has an exciting portion and a detecting portion. The exciting portion includes a first excitation coil that is wound around a non-magnetic bobbin so that a center axis direction is oriented in an x-axis direction and a second excitation coil that is wound around the non-magnetic bobbin to intersect with the first excitation coil so that a center axis direction is oriented in a y-axis direction. The detecting portion includes a detection coil that is arranged at the lower one of two intersecting portions of the first excitation coil and the second excitation coil. An eddy current measurement method for determining the thickness of a hardened layer.
    Type: Grant
    Filed: June 15, 2011
    Date of Patent: November 26, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Naotaka Ide, Takanari Yamamoto, Tatsuo Hiroshima
  • Patent number: 8575878
    Abstract: An energy converter includes a magnetism generation mechanism unit that generates a magnetic field when connected to an AC electrical power source, and a rotating mechanism unit having a single turn coil array member in which a plurality of single turn coils is disposed at a predetermined interval and a soft magnetic metal plate disposed on a side of the single turn coil array member opposite to the magnetism generation mechanism unit. The rotating mechanism unit is structured such that the single turn coil array member faces the magnetism generation mechanism unit across a predetermined magnetic gap and rotary driven by the magnetic field. Here, a drive signal period of the electrical power source is a period that maximizes an eddy current generated in the soft magnetic metal plate.
    Type: Grant
    Filed: November 26, 2009
    Date of Patent: November 5, 2013
    Assignee: TBK Co., Ltd
    Inventors: Tetsuo Sekiya, Kiyotsugu Narita
  • Patent number: 8428706
    Abstract: An apparatus for testing of electrical or physical properties of a material include a single coil sensor mounted adjacent to a sample of the material. Sheet conductance of a wide variety of materials may be measured using the single coil to determine if the material conforms to generally accepted standards for the use to which the material will be put. In some examples, the material is a semiconductor wafer or flat panel. In other examples, the material is the body tissue of a patient. A non-invasive technique using the apparatus is also disclosed for monitoring the health of patient tissue such as musculature, and/or to determine whether healthy circulation is present, by measuring the conductance of the patient tissue in response to a magnetic field applied by the single coil. The single coil may be hand held, or it may be movable using an automated positioning system under computer control.
    Type: Grant
    Filed: November 10, 2006
    Date of Patent: April 23, 2013
    Inventors: Austin Blew, Michael Bronko, Steven C. Murphy, Steve Bell
  • Patent number: 8324894
    Abstract: A linearly polarized eddy current sensor including a source antenna and a parasitic antenna coupled to the source antenna, serves as a high sensitivity tool for the measurement of the surface impedance of sheet goods without requiring contact with the sample. Sheet goods can have an anisotropic, frequency-dependent surface impedance that is sensitive to minor changes in configuration of the sample. Because the electric field induced by the sensor is linearly polarized, measurement of directionally dependent sheet impedance can be achieved. The measurement is performed with the resonant device operating in resonance mode whereby the immediate proximity of the material to be measured causes damping and shifting of the coupled loop resonance. The resonant frequency of the sensor can be tuned by making changes to its geometry.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: December 4, 2012
    Assignee: Arizona Board of Regents for and on behalf of Arizona State University
    Inventors: Rodolfo E. Diaz, Jeffrey W. Peebles, Richard LeBaron, Richard Ormeno
  • Patent number: 8319494
    Abstract: A pipeline inspection tool includes two pole magnets oriented at an oblique angle relative to the central longitudinal axis of the tool body. An array of sensor coil sets is located between opposing edges of the two pole magnets and oriented perpendicular to the central longitudinal axis. Each sensor coil set includes a transmitter coil and two opposing pairs of receiver coils that are gated to receive reflections from the wall of a tubular member. Because the line of sensor coils is rotated relative to the magnetic bias field, the receiver coils are in-line with, and have the same angular orientation as, the transmitter coil. The tool provides improved sensitivity to small defects, substantial decrease in RF pulser power requirements, full circumferential coverage, self-calibration of the transmitted signals, and less interference between transmitter coils caused by acoustic ring around.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: November 27, 2012
    Assignee: TDW Delaware Inc.
    Inventors: James Simek, Jed Ludlow, John H. Flora, Syed M. Ali, Huidong Gao
  • Patent number: 8314713
    Abstract: A method for monitoring the operation of a metal detection system that comprises a balanced coil system with a transmitter coil that is connected to a transmitter unit, which provides transmitter signals having a fixed or variable transmitter frequency, and with a first and a second receiver coil that provide output signals to a receiver unit. A system adapted to operate according to an exemplary method is also provided. According to one embodiment, a carrier signal having the transmitter frequency and a monitoring signal having a monitoring frequency are provided to a modulation unit that suppresses the carrier signal and provides a modulated monitoring signal, which is supplied to a monitoring coil that is inductively coupled with at least one of the receiver coils, whose output signals are demodulated in a demodulation unit that provides a demodulated monitoring signal, which is compared in phase and/or in amplitude with a reference.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: November 20, 2012
    Assignee: Mettler-Toledo Safeline Limited
    Inventor: Stephen McAdam
  • Patent number: 8305088
    Abstract: A process for differentiating conductive and/or ferromagnetic objects (O) in a material stream (2) comprises generating an electromagnetic alternating field by exciting a coil (S) with a sinusoidal voltage (ue(t)) of a constant frequency (fM), detecting an impedance change in the coil, which has been caused by an object (O), by determining at least one pair of values from a peak value (ÎM) and a phase shift (?m) of the coil current (iM(t)) toward the excitation potential (ue(t)) of the coil, and determining the material by comparing the peak values (ÎM) and phase shifts (?m) with reference values, wherein the peak values (ÎM) of the coil current (iM(t)) are calculated at at least one measuring phase angle (?m) with the aid of a window comparator having a constant window width (?i), wherein the time (?tM) between the window inlet point (p4) and the window outlet point (p6) of the coil current (iM(t)) is measured and the gradient of the current profile (iM(t)) is calculated from the window width (?i) and the me
    Type: Grant
    Filed: February 22, 2008
    Date of Patent: November 6, 2012
    Assignee: EVK di Kerschhaggl GmbH
    Inventors: Michael Kiss, Bernhard Kohla, Bernd Graze
  • Patent number: 8274278
    Abstract: An automated, non-destructive anhysteretic magnetization characterization method for studying and modeling soft magnetic materials. This measurement method employs a “reading-waveform” that allows multiple points of reference to be established in tracing out the B waveform. In using the reference values from this waveform, the components of B that cannot be measured directly may be calculated with precision. In turn, the initial magnitude of the B waveform is identified as the unknown component of the anhysteretic state. The processes can be repeated for different values of static fields as well as a function of temperature to produce a family of anhysteretic magnetization curves. The core characterization was performed without physically altering the core, so that the true anhysteretic magnetization curve, and the true B-H loop under applied bias H, is measured.
    Type: Grant
    Filed: December 10, 2009
    Date of Patent: September 25, 2012
    Assignee: University of South Florida
    Inventors: Jeremy Walker, Stephen E Saddow
  • Patent number: 8207731
    Abstract: A metal detector used for identifying contaminants in packages on a conveyor. The detector includes coils a search head and an analog to digital converter generating a reactive signal and a resistive signal in response to the presence of a contaminant. During a learning mode a sample product passes through the metal detector providing a representative product effect signal which is stored by the reactive learn memory and the resistive learn memory. The learn memory values provide a reference value subtracted from each product signal during a normal production cycle, canceling the product effect caused by contaminants in individual packages. The product effect is monitored during successive cycles composed of a series of packages undergoing normal inspection by the metal detector. A tracking processor averages the product effect signal produced by the individual packages and continuously updates a product effect trend signal that is subtracted from each product signal.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: June 26, 2012
    Assignee: Thermofisher Scientific
    Inventor: Sergey A. Moskalenko
  • Patent number: 8183862
    Abstract: An eddy current testing device which confirms that a change in characteristics of a target object is detected regardless of the magnitude of the change and specifying the position of a portion from which the change is detected. The device uses an eddy current probe to inspect a bent portion of a metal body, and has an inspection controller and a display unit. The inspection controller calculates a phase angle of a signal detected by the eddy current probe and generates flaw identification image data that indicates an area (or an area of the signal detected and determined to correspond to a flaw signal, based on the phase angle of the detected signal) of a flaw signal in coordinates in which the position of the portion of the target object is plotted along a coordinate axis. The display unit displays the flaw identification image data.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: May 22, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Hisashi Endo, Akira Nishimizu, Hirofumi Ouchi, Yoshio Nonaka
  • Patent number: 8120456
    Abstract: A balancing circuit for a metal detector. The metal detector includes an oscillating power source, a transmit coil connected to the oscillating power source, first and second receive coils inductively coupled to the transmit coil, a first amplitude balancing circuit connected to the first receive coil, and a first phase balancing circuit connected to the first receive coil. The first phase balancing circuit includes a capacitor and a variable resistor.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: February 21, 2012
    Assignee: Carnes Company, Inc.
    Inventor: Joseph S. Simon
  • Patent number: 8085863
    Abstract: A radio receiver includes an in-phase channel and a quadrature channel, the channels being provided in parallel at a respective input with quadrature modulated radio frequency signals; and an error correction loop for detecting and correcting an imbalance in gain between at least part of the in-phase channel and a corresponding part of the quadrature channel, wherein the error correction loop comprises: a detector adapted to calculate Error_detnew=|I?|?|Q?|, where I? and Q? are the in-phase and quadrature channels respectively; a loop filter arranged to receive Error_detnew from the detector and calculate loop_filter_outnew+=Ki * Error_detnew, where Ki is the loop filter constant and loop_filter_outnew has an initial value of 1; and a multiplier arranged to receive loop_filter_outnew from the loop filter and adjust the signal of the quadrature channel by multiplying the signal by loop_filter_outnew.
    Type: Grant
    Filed: July 10, 2007
    Date of Patent: December 27, 2011
    Assignee: Nokia Corporation
    Inventor: Chandra Gupta
  • Patent number: 8008913
    Abstract: Variations in the lift-off separation between a probe and the surface of a structure to be tested often mask the detection of defects in the structure. A method and apparatus for automatically classifying and compensating for variations in the lift-off is described. A reference signal at a known lift-off may be weighted by a corresponding calculated ratio parameter and subtracted from a test signal to compensate for lift-off. A number of reference signals are preferably obtained and the largest magnitude gradient for each reference signal is preferably determined. The largest magnitude gradient for subsequent test signals is also obtained and the corresponding reference signal with the closest largest magnitude gradient to the test signal is identified and the corresponding reference signal is selected in the related compensation procedure. Such a method has been found to restore the signal such that lift-off is removed and defects are easily identified.
    Type: Grant
    Filed: June 6, 2008
    Date of Patent: August 30, 2011
    Assignee: GE Inspection Technologies, Ltd
    Inventors: Xiaoyu Qiao, John Hansen
  • Patent number: 7977938
    Abstract: A metal detector for detecting the presence of a ferrite object in the proximity of inductively coupled sensor having overlapping D shaped transmitter and receiver coils. The metal detector has a phase shift circuit to phase shifting a sensor output signal by a known amount and a switch operating in synchronization with an excitation signal of the sensor for sampling the amplitude of the phase shifted output signal.
    Type: Grant
    Filed: August 23, 2007
    Date of Patent: July 12, 2011
    Assignee: Solar Wide Industrial Ltd.
    Inventors: Hughes Sanoner, Desmond Wai Nang Tse, Lawrence Chi Hang Chan
  • Publication number: 20110074401
    Abstract: A metal detector (40) used for identifying contaminants in packages (49, 50, 51) introduced into the metal detector by a conveyor. The detector (40) includes coils (1), a search head (2) and an analog to digital converter (3) that generates a reactive signal (13) and a resistive signal (14) in response to the presence of a contaminant in the region of the coils. A high pass filter (4) receives the reactive and resistive signals (13, 14). During a learning mode a sample product is introduced into the metal detector (40) to provide a representative product effect signal which is stored by the reactive learn memory (19) and the resistive learn memory (28). The learn memory values (29, 32) are forwarded to reference processors (20, 35) to provide a reference value which is subtracted from each product signal during a normal production cycle, thereby canceling the product effect caused by each individual package as it passes through the metal detector.
    Type: Application
    Filed: September 30, 2009
    Publication date: March 31, 2011
    Inventor: Sergey A. Moskalenko
  • Patent number: 7893690
    Abstract: A balancing circuit for a metal detector. The metal detector includes an oscillating power source, a transmit coil connected to the oscillating power source, first and second receive coils inductively coupled to the transmit coil, a first amplitude balancing circuit connected to the first receive coil, and a first phase balancing circuit connected to the first receive coil. The first phase balancing circuit includes a capacitor and a variable resistor.
    Type: Grant
    Filed: July 19, 2007
    Date of Patent: February 22, 2011
    Assignee: Carnes Company, Inc.
    Inventor: Joseph S. Simon
  • Patent number: 7840370
    Abstract: Method and apparatus for monitoring the rotational speed of a shaft, in particular a shaft having a number of spaced features on or rotating with the shaft. Preferred embodiments of the invention are concerned with methods and apparatuses for processing signals in order to calculate, with high accuracy and a fast response time, the rotational speed of a gas turbine shaft. The invention recognizes that it is possible to accurately measure speed between two eddy current sensors (5, 6) by determining the time take for a turbine blade to pass therebetween provided that appropriate compensation is made for the effect of apparent changes in the magnetic distance between the sensors.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: November 23, 2010
    Assignee: Weston Aerospace Limited
    Inventors: Wojciech Konrad Kulczyk, Anthony Palmer, Matthew Clifton-Welker
  • Publication number: 20100244818
    Abstract: Method and apparatus for generating and selecting low-frequency time-domain signals capable of transducing a mammalian system, to produce an agent-specific effect on the system, are disclosed. Low-frequency time-domain signals are generated in the presence of an injected magnetic stimulus, and the resulting signals are selected by a scoring algorithm, and optionally, by testing each signal identified by the scoring algorithm for its ability to produce an agent-specific response in a in vitro system containing components that are responsive to the agent. The selected signals are used to transduce the mammalian system by applying the signals to an electromagnetic transduction coil that holds the sample.
    Type: Application
    Filed: November 20, 2007
    Publication date: September 30, 2010
    Inventors: Christopher G. Atwood, Bennett Michael Butters, John T. Butters, Shirin M. Marfatia, Gabriel Vogeli
  • Patent number: 7750626
    Abstract: A method of eddy current testing without the need for lift-off compensation. Signal response features similar to those used in pulsed eddy current techniques are applied to conventional (harmonic) eddy current methods. The described method provides advantages in terms of data storage, since only two response parameters, the amplitude and phase, are sufficient to reconstruct any sinusoidal signal, therefore allowing for scanning of large surfaces.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: July 6, 2010
    Assignees: Her Majesty the Queen in right of Canada, as represented by the Minister of National Defence of Her Majesty's Canadian Government, National Research Council of Canada
    Inventors: J. H. Vivier Lefebvre, Catalin V. Mandache
  • Publication number: 20100117638
    Abstract: The present invention relates to a magnetic sensor with a sensitivity measuring function and a method thereof. Magnetic sensitivity surfaces detect flux density, and a switching unit extracts magnetic field intensity information of each axis, and inputs it to a sensitivity calculating unit. The sensitivity calculating unit calculates the sensitivity from the magnetic field intensity information about the individual axes from the magnetic sensitivity surfaces. The sensitivity calculating unit includes an axial component analyzing unit for analyzing the flux density from the magnetic sensitivity surfaces into magnetic components of the individual axes; a sensitivity decision unit for deciding the sensitivity by comparing the individual axial components of the magnetic field intensity from the axial component analyzing unit with a reference value; and a sensitivity correction unit for carrying out sensitivity correction in accordance with the sensitivity information from the sensitivity decision unit.
    Type: Application
    Filed: March 21, 2008
    Publication date: May 13, 2010
    Applicant: ASAHI KASEI EMD CORPORATION
    Inventors: Masaya Yamashita, Yo Yamagata
  • Publication number: 20100102806
    Abstract: An arrangement for influencing and/or detecting magnetic particles, a method for adjusting such an arrangement and a method for influencing and/or detecting magnetic particles in a region of action is disclosed, which arrangement comprises selection means for generating a magnetic selection field having a pattern in space of its magnetic field strength such that a first sub-zone having a low magnetic field strength and a second sub-zone having a higher magnetic field strength are formed in the region of action, drive means for changing the position in space of the two sub-zones in the region of action by means of a magnetic drive field so that the magnetization of the magnetic particles changes locally, receiving means for acquiring signals, which signals depend on the magnetization in the region of action, which magnetization is influenced by the change in the position in space of the first and second sub-zone, wherein the receiving means comprises a first compensation means and a second compensation means t
    Type: Application
    Filed: December 17, 2007
    Publication date: April 29, 2010
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Berhard Gleich, Juergen Weizenecker
  • Patent number: 7576534
    Abstract: The system (10) and the method are used for forecasting the electrical conductivity of an anode (12) for aluminum production before the anode (12) is baked. In the system (10), at least one receiving coil (20,22) is coupled to an electromagnetic field emitting unit (14,18). A sensing device (30) is connected to the receiving coil (20,22), the sensing device (30) outputting a signal indicative of a variation of the electromagnetic field received by the receiving coil (20,22) as the crude anode (12), or a portion thereof, passes inside the receiving coil (20,22). A value indicative of the electrical conductivity of the anode (12) is then calculated using the signal from the sensing device (30) and signals previously obtained using reference anodes (12). This way, the electrical conductivity of the anodes (12) can be forecasted before the crude anodes (12) are baked.
    Type: Grant
    Filed: December 10, 2004
    Date of Patent: August 18, 2009
    Assignee: Universite Du Quebec A Chicoutimi
    Inventors: Daniel Audet, Luc Parent
  • Patent number: 7532127
    Abstract: A hand-held, wand-type buried object detector includes a motion and position sensor that provides data about the sensor head of the buried object detector. An inertial measuring device including three accelerometers and three gyroscopes is one example of a motion and position sensor. The buried object detector includes a processor/communicator device that is capable of processing the data from the motion and position sensor and communicating feedback, based on the processing results, to the operator about the operation of the buried object detector. In one example, a personal digital assistant may be configured for use as a processor/communicator device of a buried object detector.
    Type: Grant
    Filed: October 20, 2005
    Date of Patent: May 12, 2009
    Assignee: L-3 Communications CyTerra Corporation
    Inventors: Glen A. Holman, Herbert Duvoisin, Gregory W. Stilwell, Jason A. Clark, Tim L. Davis, C. Andrew Helm
  • Patent number: 7532123
    Abstract: Articles are magnetically tagged by a spatial distribution of passive magnetic elements. Each such magnetic element comprises a layer of soft magnetic material characterised by high permeability, low coercivity and a non-linear B-H characteristic, and formed as a discrete region of such material. Each such magnetic element also has at least one second layer of magnetic material capable of being permanently magnetised at least in a region adjacent the first layer to provide a magnetic bias for the magnetic element. The bias of individual such magnetic elements in the spatial distribution and the particular spatial nature of the distribution enables the article to be magnetically encoded.
    Type: Grant
    Filed: September 21, 2004
    Date of Patent: May 12, 2009
    Assignee: Linksure Ltd.
    Inventors: David Howard Arnold, Robert Julian Dickinson
  • Patent number: 7519487
    Abstract: The alternating current potential drop ACPD technique is used to monitor surface cracks in electrical conductors. At high frequencies, the current flows in a superficial skin layer. Two distinct solutions are currently available for the thin and thick skin cases. However, there is no general solution that bridges these two modes in a seamless fashion. A numerical model is used to analyze the ACPD of a surface crack with uniform depth. A general solution is given that bridges the thin and thick skin solutions, which closely matches the numerical results, irrespective of the skin thickness. Methods for estimating depth of cracks are provided for surface penetrating cracks and back cracks.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: April 14, 2009
    Assignee: Technion Research and Development Foundation Ltd.
    Inventors: Hagit Saguy, Daniel Rittel
  • Publication number: 20090021251
    Abstract: A balancing circuit for a metal detector. The metal detector includes an oscillating power source, a transmit coil connected to the oscillating power source, first and second receive coils inductively coupled to the transmit coil, a first amplitude balancing circuit connected to the first receive coil, and a first phase balancing circuit connected to the first receive coil. The first phase balancing circuit includes a capacitor and a variable resistor.
    Type: Application
    Filed: July 19, 2007
    Publication date: January 22, 2009
    Inventor: Joseph S. Simon
  • Publication number: 20080297158
    Abstract: An implementation of a direction finding and magnetic nulling metal detector is provided. Some embodiments of the present invention provide for a metal detector having multiple resonant circuits and associated coils for transmitting a primary transmit signal, transmitting a magnetic nulling signal, and receiving a receive signal. A controller includes logic to process the generate the transmit signals and to process the received signal in order to determine a gradient vector along one or two dimensions, a depth and whether or not a metal object is ferrous.
    Type: Application
    Filed: May 31, 2007
    Publication date: December 4, 2008
    Applicant: Zircon Corporation
    Inventors: Charles E. Heger, Anthony J. Rossetti
  • Publication number: 20080290866
    Abstract: A method and apparatus for conducting eddy current testing of a test object is disclosed, comprising the steps of generating a digital drive signal, converting the digital drive signal to an analog drive signal to drive a coil in a probe; placing the probe in proximity to a test object; receiving an electromagnetic field generated by the test object, which generates an analog return signal; converting the analog return signal to a digital return signal; measuring the amplitude of the digital return signal; measuring the phase shift of the digital return signal compared to the digital drive signal; determining the phase shift angle of the digital return signal based on the phase shift; determining the quadrature components of the digital return signal based on the digital return signal amplitude and the phase shift angle; and analyzing the quadrature components of the digital return signal to determine a material characteristic of the test object.
    Type: Application
    Filed: May 23, 2007
    Publication date: November 27, 2008
    Inventors: John M. Cuffe, Mark H. Feydo
  • Publication number: 20080278154
    Abstract: The invention relates to a device for determining an object (14, 16), comprising an inductive sensor (8), a control unit (10) for evaluating phase information of the inductive sensor (8) and display means (4, 4a-d). According to the invention, the display means (4, 4a-d) are configured to indicate a characteristic of the object (14, 16) and the control unit (10) is provided to control the display means (4, 4a-d) in accordance with the phase information.
    Type: Application
    Filed: December 15, 2006
    Publication date: November 13, 2008
    Inventors: Reiner Krapf, Michael Mahler, Christoph Wieland, Ulli Hoffmann
  • Patent number: 7345474
    Abstract: A detector for magnetizable materials operates remotely to determine a amplitude and phase modification of an exciting magnetic field caused by the magnetizable materials. These amplitude and phase measurements are used to create a phase-amplitude trajectory in phase amplitude space, which may be finely divided to distinguish among a number of different types of components.
    Type: Grant
    Filed: July 12, 2005
    Date of Patent: March 18, 2008
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Jonathan R. Engdahl, Ira B. Goldberg
  • Patent number: 7285953
    Abstract: A device for producing a detection signal when interfering, preferably metallic conductive pieces occur in an at least largely non-conductive conveyor stream. An alternating electromagnetic field is built up by an alternating current generator through a transmission coil in a segment of the conveyor stream to be monitored. The changes in amplitude and phase of the alternating electromagnetic field are detected by a coil system that feeds an evaluating circuit for deriving the detection signal, which, when an interfering piece appears, causes a stoppage of the conveyor stream for the purpose of removing the interfering piece. A resetting device (reset button) is also provided which is able to cancel the conveyor stoppage. A device is also provided for blocking the resetting device, controlled by the evaluating circuit, which disables the resetting device as long as the evaluating circuit still emits a detection signal.
    Type: Grant
    Filed: August 1, 2003
    Date of Patent: October 23, 2007
    Assignee: Firma Mesutronic Geratebau GmbH
    Inventors: Manfred Artinger, Karlheinz Dürrmeier
  • Patent number: 7241630
    Abstract: A method of determining the number of magnetic particles within a sample using a tuned circuit having a capacitor and a coil. The method comprises: a. determining the difference in the resonant frequency of the tuned circuit when the sample is exposed to a magnetic field generated by the coil and when the sample is not exposed to the magnetic field generated by the coil; and b. using the difference in the resonant frequency to determine the number of magnetic particles within the sample.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: July 10, 2007
    Assignee: Randox Laboratories, Ltd.
    Inventors: Peter Hawkins, Richard William Luxton