Electro-magnet Or Inductor (e.g., Flux Valve, Etc.) Patents (Class 33/361)
  • Patent number: 11934355
    Abstract: A system and method for providing a distributed measurement system. The system performs operations that include receiving, via a user interface of a user device, a request from a requestor to access a data file of a project. The project includes a plurality of data files including the data file, and at least one of the one or more data files is generated based at least in part on measurement data output from a measurement device. Based on determining that the requestor has permission to access the data file, one or more editing options are provided for editing the data file. The one or more editing options vary based at least in part on one or both of a characteristic of the user device and a characteristic of the data file. The data file is edited in response to receiving an editing request.
    Type: Grant
    Filed: January 14, 2022
    Date of Patent: March 19, 2024
    Assignee: FARO Technologies, Inc.
    Inventors: Oliver Zweigle, Ahmad Ramadneh, Aleksej Frank, Joao Santos
  • Patent number: 11226937
    Abstract: A system and method for providing a distributed measurement system. The system performs operations that include receiving, via a user interface of a user device, a request to access a data file of a project. The project includes one or more data files including the data file, and at least one of the one or more data files is generated based at least in part on measurement data output from a measurement device. One or more editing options are provided for editing the data file. The one or more editing options vary based at least in part on one or both of a characteristic of the user device and a characteristic of the data file. The data file is edited in response to receiving an editing request that includes an editing option of the one or more editing options.
    Type: Grant
    Filed: March 21, 2019
    Date of Patent: January 18, 2022
    Assignee: FARO TECHNOLOGIES, INC.
    Inventors: Oliver Zweigle, Ahmad Ramadneh, Aleksej Frank, Joao Santos
  • Patent number: 11143527
    Abstract: A position sensor system comprising: a magnetic field generator movable relative to two sensor devices or vice versa. The system has at least one processor adapted with a special algorithm for determining a position of the magnetic field generator in a manner which is highly robust against a disturbance field. A method for determining the position of the magnetic field generator based on a set of equations, in particular a set of linear equations which allows to completely eliminate the external disturbance field.
    Type: Grant
    Filed: June 26, 2019
    Date of Patent: October 12, 2021
    Assignee: MELEXIS TECHNOLOGIES SA
    Inventor: Javier Bilbao De Mendizabal
  • Patent number: 10885658
    Abstract: The present disclosure relates to methods, apparatus or systems for determining a final pose (21) of a rendering device. An initial pose is associated with the rendering device. A module (25) determines an intermediate pose (26) according to data from absolute pose sensors (23) and/or differential pose sensors (22). A module (27) determines the final pose (21) according to, first, a difference between the intermediate pose (26) and the initial pose information, second, the data from differential pose sensors (22), and third an evaluation of the visual perception of movements for current images (24) displayed on the rendering device.
    Type: Grant
    Filed: April 6, 2017
    Date of Patent: January 5, 2021
    Assignee: InterDigital CE Patent Holdings, SAS.
    Inventors: Julien Fleureau, Franck Galpin, Xavier Burgos
  • Patent number: 10355947
    Abstract: An information providing method is an information providing method for consumer electronics devices, a display device, and a server, all of which are connected via a public network, the information providing method including: (a) receiving, by the server from the consumer electronics devices, information pieces on the consumer electronics devices; (b) filtering, by the server, the information pieces on the consumer electronics devices received in step (a), to obtain one or more filtered information pieces, and performing, by the server, processing for generating display information for display, by the display device, in a specific display format; and (c) transmitting, by the server, the display information generated in step (b) to the display device.
    Type: Grant
    Filed: May 13, 2014
    Date of Patent: July 16, 2019
    Assignee: PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA
    Inventors: Shigehiro Iida, Kazunori Yamada, Mitsuhiro Aso, Michiko Sasagawa, Masayuki Hiromoto
  • Patent number: 9222774
    Abstract: Disclosed is a clinocompass for measuring a strike and a dip on an irregular geological outcrop and a method of measuring the strike and the dip by using the same. Since the level meter of the clinometer is supported by providing a support force and a fixing force on an irregular geological outcrop having no exposed flat plane, the clinocompass serves as a supporting member or a fixing member for the measurement of the strike and the dip on an irregular geological outcrop having no exposed flat plane. Accordingly, the clinocompass has a structure to measure the strike and the dip suitable for the geological structure and the orientation of the outcrop having no exposed flat plane, so that the strike and the dip are usefully measured.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: December 29, 2015
    Assignee: KOREA INSTITUTE OF GEOSCIENCE AND MINERAL RESOURCES
    Inventors: Raehee Han, Ki-Sung Sung, Jeong-Chan Kim
  • Patent number: 9207056
    Abstract: Portable instrument for measuring dimensions, comprising a scale, a position sensor capable of being displaced relative to the scale and a watertight housing defining an internal volume comprising the display, the electronic reading circuit and a power source. Additional functional layers, for example an over-molded elastomer thermoplastic layer and a metallic plate, protect the instrument and add to it specific tactile and visual qualities.
    Type: Grant
    Filed: January 23, 2013
    Date of Patent: December 8, 2015
    Assignee: TESA SA
    Inventor: Frédéric Biselx
  • Patent number: 9110123
    Abstract: A semiconductor process and apparatus provide a high-performance magnetic field sensor with three differential sensor configurations which require only two distinct pinning axes, where each differential sensor is formed from a Wheatstone bridge structure with four unshielded magnetic tunnel junction sensor arrays, each of which includes a magnetic field pulse generator for selectively applying a field pulse to stabilize or restore the easy axis magnetization of the sense layers to orient the magnetization in the correct configuration. prior to measurements of small magnetic fields. The field pulse is sequentially applied to groups of the sense layers of the Wheatstone bridge structures, thereby allowing for a higher current pulse or larger sensor array size for maximal signal to noise ratio.
    Type: Grant
    Filed: November 4, 2014
    Date of Patent: August 18, 2015
    Assignee: EVERSPIN TECHNOLOGIES, INC.
    Inventors: Bradley Engel, Phillip Mather
  • Publication number: 20150000145
    Abstract: Apparatus and methods to compensate hard iron and soft iron magnetic interference in magnetic sensing devices are described. Hard and soft iron interference may be modeled using an ellipsoidal surface generated by a plurality of magnetic field measurements. A displacement of the ellipsoid from a reference frame origin corresponds to hard iron or permanent magnetic field interference. A shape and orientation of the ellipsoid corresponds to soft iron magnetic field interference. The ellipsoidal surface may be analyzed to obtain magnetic field compensation values for cancelling hard iron and soft iron interference.
    Type: Application
    Filed: June 18, 2014
    Publication date: January 1, 2015
    Applicant: STMicroelectronics (China) Investment Co. Ltd.
    Inventors: Travis Tu, Shu Fang
  • Patent number: 8713809
    Abstract: Provided is a flux gate sensor comprising the following: a magnetic core having a first wiring layer formed on a board, a first insulating layer formed in such a way as to cover the aforementioned first wiring layer, and a magnetic core which is formed on the aforementioned first insulating layer and which has a central portion and an end portion that continues to the aforementioned central portion, that has a width larger than the width of the aforementioned central portion, and that is located on either side of the aforementioned central portion; a second insulating layer which covers the aforementioned magnetic core and which is formed on the aforementioned first insulating layer; and a second wiring layer formed on the aforementioned second insulating layer.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: May 6, 2014
    Assignee: Fujikura Ltd.
    Inventors: Kenichi Ohmori, Takuya Aizawa, Osamu Nakao
  • Patent number: 8456159
    Abstract: A stabilized field sensor apparatus collects field data, in particular magnetic field data, with reduced motion noise. The apparatus includes a tear drop shaped housing, a tow frame in the housing, a plurality of vibration isolating dampers spaced around the frame, a base assembly mounted to the dampers, a support pedestal having a bottom end fixed to the base assembly and an upper free end, a single spherical air bearing connected to the upper free end of the pedestal, an instrument platform with a lower hollow funnel having an upper inside apex supported on the air bearing for a one point support, principal and secondary gyro stabilizers for maintaining pivotal and rotational stability, and at least one field sensor mounted to the instrument platform for collecting the field data while being stabilized against motion noise including vibration, pivoting and rotation from the base assembly, from the tow frame and from the housing.
    Type: Grant
    Filed: January 15, 2010
    Date of Patent: June 4, 2013
    Assignee: Vale S.A.
    Inventors: Benjamin David Polzer, Gordon Fox West, Peter Whyte Walker, Peter Anthony Hurley, Robert Leslie Scott Hogg
  • Publication number: 20130104410
    Abstract: Electronic devices may be provided with compasses for detecting the Earth's magnetic field. Electronic devices may be provided with electronic components that generate interfering magnetic fields for the compass. Electronic components may be coupled between a power supply line and a power return line on a printed circuit. The power return line may be configured to generate a compensating magnetic field to counteract the interfering magnetic fields. The power return line may be formed parallel to the power supply line. The power supply line may have multiple branches equidistant from the compass. The power return line may have a portion closer to the compass than the power supply line and the electronic component. The power return line may have multiple branches, may be provided with resistors on each branch and may include a portion of a circular loop the runs around the compass on the printed circuit board.
    Type: Application
    Filed: October 27, 2011
    Publication date: May 2, 2013
    Inventors: Jeremy L. Wade, Michael Eng, Ryan J. Garrone
  • Patent number: 8321161
    Abstract: The invention as disclosed is an autonomous magnetic measurement system for monitoring the background magnetic fields associated with power lines, electronic devices, electronic vehicles and the Earth's background magnetic field. The components of the autonomous magnetic measurement system include a series of three axis analog magnetic sensors, a fluxgate compass, and a programmable micro-controller. The micro-controller receives data from the sensor and compass and is programmed to autonomously detect magnetic signals having particular characteristics of interest.
    Type: Grant
    Filed: September 17, 2010
    Date of Patent: November 27, 2012
    Assignee: The United States of America as represented by the Secretarty of the Navy
    Inventors: Anthony B. Bruno, Rolf G. Kasper
  • Publication number: 20120151786
    Abstract: Provided is a flux gate sensor comprising the following: a magnetic core having a first wiring layer formed on a board, a first insulating layer formed in such a way as to cover the aforementioned first wiring layer, and a magnetic core which is formed on the aforementioned first insulating layer and which has a central portion and an end portion that continues to the aforementioned central portion, that has a width larger than the width of the aforementioned central portion, and that is located on either side of the aforementioned central portion; a second insulating layer which covers the aforementioned magnetic core and which is formed on the aforementioned first insulating layer; and a second wiring layer formed on the aforementioned second insulating layer.
    Type: Application
    Filed: November 18, 2011
    Publication date: June 21, 2012
    Applicant: Fujikura Ltd.
    Inventors: Kenichi OHMORI, Takuya Aizawa, Osamu Nakao
  • Publication number: 20120139744
    Abstract: A device for indicating a direction or axis in three dimensions to a user, comprises an indicator member (10, 11) configured to indicate a direction in any three dimensional direction,—a static member (12) for mounting the indicator member; and an actuator arrangement (12, 14, 15) configured to urge the indicator member to rotate relative to the static member in any angle about a single point of rotational symmetry. A direction indicating arrangement calculates an angle in three dimensions for indicating a direction and comprises a drive arrangement (13, 14, 15) that drives a pointing device (10, 11) to point in the calculated direction.
    Type: Application
    Filed: April 6, 2010
    Publication date: June 7, 2012
    Inventor: Michael Ridgway
  • Patent number: 8170886
    Abstract: Systems, methods, and apparatus to generate an energy consumption index are disclosed. In one described example, a method to generate an energy consumption index is disclosed, the method including measuring resources consumed at a home associated with a first person and calculating a home energy value indicative of the resources consumed at the home and measuring resources consumed by the person while located outside the home and calculating an out of home energy value indicative of the resources consumed by the person while located outside the home. The example method further includes identifying goods purchased by the person and calculating a purchase energy value indicative of the resources associated with the purchased goods, and generating an energy consumption index associated with the person based on the home energy value, the out of home energy value, and the purchase energy value.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: May 1, 2012
    Assignee: The Nielsen Company (U.S.), LLC
    Inventor: Robert A. Luff
  • Patent number: 8108171
    Abstract: Calibration systems and methods simultaneously calibrate a magnetic compass and gyroscopes. An exemplary embodiment rotates the field calibration system. Based upon the rotation sensed by the magnetic compass and the gyroscopes, the field calibration system determines compensation for both the magnetic compass and the gyroscopes.
    Type: Grant
    Filed: September 14, 2009
    Date of Patent: January 31, 2012
    Assignee: Honeywell International, Inc.
    Inventor: Tom Judd
  • Patent number: 7895759
    Abstract: An electronic device includes resistor, a pointer, a measuring module, a calculating module, and a display module. The resistor has a reference point corresponding with a reference direction. The resistor defines a circle. The pointer has a pointing terminal contacting the resistor at a contacting point corresponding with a reference direction. The pointer is pivotablely mounted about a centre of the circle. The pointer is aligned with the magnetic field of the Earth, and the measuring module measures the voltage between the contacting point and the reference point. The calculating module calculates an angle between the current direction and the reference direction according to the voltage between the contacting point and the reference point of the resistor. The display module displays corresponding direction information according to the angle.
    Type: Grant
    Filed: October 30, 2009
    Date of Patent: March 1, 2011
    Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventor: Zu-Hong Hu
  • Patent number: 7873491
    Abstract: In an AC magnetic tracker one or more multi-axis field sources, each operating at a different frequency, or frequency set, are detected and tracked in three-dimensional space, even when wireless or otherwise not physically connected to the tracking system. Multiple sources can be tracked simultaneously as they each operate with their own unique detectable set of parameters. The invention not only provides the ability to uniquely identify one or more sources by their frequencies, but also to synchronize with these frequencies in order to measure signals that then allow tracking the position and orientation (P&O) of the source(s). Further, these sources need not be present at the time of system start-up but can come and go while being detected, discriminated and tracked. It also should be noted that application of such systems in multiples with more sensors not synchronized to a source or sources also could be employed to give the reverse appearance of a known source phase and incoherency with the sensors.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: January 18, 2011
    Assignee: Alken, Inc.
    Inventors: Robert F. Higgins, Herbert R. Jones, Jr., Allan G. Rodgers
  • Publication number: 20100313434
    Abstract: An electronic device includes resistor, a pointer, a measuring module, a calculating module, and a display module. The resistor has a reference point corresponding with a reference direction. The resistor defines a circle. The pointer has a pointing terminal contacting the resistor at a contacting point corresponding with a reference direction. The pointer is pivotablely mounted about a centre of the circle. The pointer is aligned with the magnetic field of the Earth, and the measuring module measures the voltage between the contacting point and the reference point. The calculating module calculates an angle between the current direction and the reference direction according to the voltage between the contacting point and the reference point of the resistor. The display module displays corresponding direction information according to the angle.
    Type: Application
    Filed: October 30, 2009
    Publication date: December 16, 2010
    Applicants: HONG FU JIN PRECISION INDUSTRY (ShenZhen) CO., ., HON HAI PRECISION INDUSTRY CO. LTD.
    Inventor: ZU-HONG HU
  • Publication number: 20100199506
    Abstract: The invention proposes a device for mechanically locating and reading the setting of an adjustable magnetic valve for controlling the flow of a fluid in a predetermined direction, and which is not particularly sensitive to the Earth's magnetic field, of simple and economical design, and which makes it possible, in a single step, to locate the magnetic centre of the valve and to determine the setting of the valve. To these ends, the subject of the invention is a device comprising a magnetic compass (10) and an alignment mark for aligning the magnetic compass (10) with respect to the direction in which the fluid flows, in which device the magnetic compass comprises a reference plane (Pr) and a magnetic indicator (12) which is mounted such that it can pivot in all three dimensions of space under the effect of the magnetic field of the valve.
    Type: Application
    Filed: February 12, 2009
    Publication date: August 12, 2010
    Inventors: Christophe Moureaux, Philippe Negre
  • Patent number: 7635930
    Abstract: At least one exemplary embodiment is directed to a stage apparatus which includes a stage movable in a first direction, a linear motor configured to drive the stage in the first direction, a magnet unit having first magnets disposed on the stage and second magnets disposed at both ends of a stroke of the stage such that the same poles of the first and second magnets face each other, and a supporting member supporting the second magnets. The supporting member is supported movably in the first direction.
    Type: Grant
    Filed: May 25, 2007
    Date of Patent: December 22, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventor: Shinji Ohishi
  • Patent number: 7379814
    Abstract: An electronic compass system includes a magnetic sensor circuit having at least two sensing elements for sensing perpendicular components of the Earth's magnetic field vector. A processing circuit is coupled to the sensor circuit to filter, process, and compute a heading. The processing circuit may determine whether too much noise is present in the output signals received from said magnetic sensor circuit as a function of the relative strength of the Earth's magnetic field vector. The magnetic sensor circuit may include three magnetic field sensing elements contained in a common integrated package having a plurality of leads extending therefrom for mounting to a circuit board. The sensing elements need not be perpendicular to each other or parallel or perpendicular with the circuit board. The electronic compass system is particularly well suited for implementation in a vehicle rearview mirror assembly.
    Type: Grant
    Filed: August 21, 2007
    Date of Patent: May 27, 2008
    Assignee: Gentex Corporation
    Inventors: Harold C. Ockerse, Jon H. Bechtel, Mark D. Bugno
  • Patent number: 7181857
    Abstract: A geomagnetic sensor for auto-calibration of a deviation and a method of using the geomagnetic sensor. The geomagnetic sensor includes a geomagnetic detector including X-axis and Y-axis fluxgates orthogonal to each other and receiving a drive signal to detect an electromotive force corresponding to a geomagnetism, a signal processor converting the electromotive force output from the geomagnetic detector into X-axis and Y-axis output values and outputting the X-axis and Y-axis output values, and a drive signal generator applying the drive signal to the geomagnetic detector. Each of the X-axis and Y-axis fluxgates includes cores, a solenoid type exciting coil, and at least two detection coils winding around the cores in a solenoid form. Accordingly, as an azimuth is measured using output values detected by the separated detection coil, the azimuth can be exactly and easily detected regardless of an external magnetic field.
    Type: Grant
    Filed: August 9, 2005
    Date of Patent: February 27, 2007
    Assignee: Samsung Electronics Mechanics Co., Ltd.
    Inventors: Seung-wan Lee, Sang-on Choi
  • Patent number: 7168177
    Abstract: There are provided a method and apparatus for determining a geomagnetic field by using a compass and a method and apparatus for determining an azimuth angle of a moving object using the method and apparatus for determining a geomagnetic field. The method of determining a geomagnetic field by using a compass includes defining an allowable magnetic field range used to determine a valid geomagnetic region; calculating a magnitude of a magnetic field in a geomagnetic-field validity test region by using a compass; and if the magnitude of the magnetic field is within the allowable magnetic field range, determining that the geomagnetic-field validity test region is the valid geomagnetic region, and if not, determining that there is applied an external magnetic field disturbance. Accordingly, since an error of an azimuth angle of the compass due to an external magnetic field disturbance can be determined, it is possible to accurately detect a valid azimuth angle of the compass.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: January 30, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Woong Kwon, Kyung-shik Roh, Woo-sup Han, Young-bo Shim, Sang-on Choi, Ki-cheol Park
  • Patent number: 7168176
    Abstract: A geomagnetic sensor which informs a user that information with respect to a distorted azimuth angle may be detected. The geomagnetic sensor includes a geomagnetism detection module including an X axis fluxgate and a Y axis fluxgate orthogonal to each other and detecting a predetermined amount of electrical signals corresponding to a geomagnetism of each of the fluxgates; a signal processing unit for converting the electrical signal output from the geomagnetism detection module to predetermined X axis and Y axis output values and outputting them; a display unit for displaying a predetermined warning message on a screen; and a control unit for determining whether the output values of the X and Y axes are distorted, and controlling the display unit to display the predetermined warning message upon determination that the output values are distorted. Accordingly, the possibility of a distorted azimuth angle may be detected and informed to a user.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: January 30, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Woo-jong Lee, Sang-on Choi
  • Patent number: 7134213
    Abstract: A magic compass that gives the illusion it defies the laws of nature, providing usage as an aid for locating the direction of prayer as well as a novel promotional device for companies, having a magnetized compass needle (16) which is attached via a linking means to a non-magnetic pointer (22). This linking means, which can be rigid (11) or non-rigid (29), allows the non-magnetic pointer (22) to be angularly displaced from the magnetized compass needle (16). This linkage also provides the means for the non-magnetic pointer (22) to rotate and pivot freely via the inertia of the magnetized needle (16). A partition (20) hides the magnetized needle (16) below, and simultaneously creates a compass face for the non-magnetic pointer above. The non-magnetic pointer (22) is designed and shaped to appear identical to a true magnetized compass needle (32).
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: November 14, 2006
    Inventor: Mark Alan Ashin
  • Patent number: 7127369
    Abstract: A system with a sensor assembly is used to determine direction of movement of an object so that accuracy of position calculation is improved. The sensor assembly measures at least two operational characteristics and generates corresponding operational characteristic signals. A control unit monitors and compares transitions of the signals to more accurately determine direction of movement for the object.
    Type: Grant
    Filed: October 9, 2002
    Date of Patent: October 24, 2006
    Assignee: Siemens VDO Automotive Corporation
    Inventors: Tomohiro Fukumura, Sanjaya Kumar Dash
  • Patent number: 7053608
    Abstract: According to some embodiments of the present invention, a magnetometer includes at least one sensor for sensing a magnetic field component, a biasing circuit, and a processor. The sensor generates an output signal having a signal characteristic that varies in response to the sensed magnetic field component and in response to an applied bias. The biasing circuit dynamically biases the sensor in response to a bias setting signal. The processor is coupled to receive the output signal from the sensor and coupled to the biasing circuit. The processor is operable to generate the bias setting signal and thereby control the biasing circuit to dynamically bias the sensor such that the signal characteristic of the output signal is maintained in a target range. The processor determines the magnetic field component sensed by the sensor as a function of the bias setting applied to the sensor.
    Type: Grant
    Filed: October 15, 2003
    Date of Patent: May 30, 2006
    Assignee: Gentex Corporation
    Inventors: Timothy R. Friend, Jon H. Bechtel
  • Patent number: 6972563
    Abstract: A single-axis, fluxgate magnetometer apparatus comprises: an excitation subassembly comprising a toroidal core wound with a predetermined number of turns of an excitation coil; and a pick up subassembly comprising a coil form including a hollow chamber, and a predetermined number of turns of a pick up coil wound on the coil form about the hollow chamber, the excitation subassembly disposed in the hollow chamber of the coil form and secured in the hollow chamber at a desired position. A method of adjusting the single-axis, fluxgate magnetometer apparatus comprises the steps of: applying an excitation signal to the excitation coil while disposed in the hollow chamber; monitoring a signal waveform of the pick up coil responsive to the excited excitation coil; adjusting the position of the excitation subassembly in the hollow chamber to effect a desired signal waveform of the pick up coil; and securing the excitation subassembly in the hollow chamber at the position that provides the desired signal waveform.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: December 6, 2005
    Assignee: Rosemount Aerospace Inc.
    Inventor: Felix Goldenberg
  • Patent number: 6831457
    Abstract: The present invention is a two-dimensional magnetic sensor having a first magneto-impedance sensor element including a first magneto-sensitive element and a first electro-magnetic coil which is wound around said first magneto-sensitive element; a second magneto-impedance sensor element including a second magneto-sensitive element and a second electro-magnetic coil which is wound around said second magneto-sensitive element; and an integrated circuit including an oscillator, a current switching element, a voltage detector, and an amplifier.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: December 14, 2004
    Assignee: Aichi Micro Intelligent Corporation
    Inventors: Yoshinobu Honkura, Masaki Mori, Michiharu Yamamoto, Yoshiaki Koutani
  • Patent number: 6771066
    Abstract: A printed circuit fluxgate sensor for use in magnetic gradient detection devices and the like includes a highly magnetically saturable core formed as a flat, closed loop that is bonded between two planar substrate members. An excitation coil is formed on the outer surfaces of the substrate members by masking and etching a layer of a conductive metal in a pattern of tracks that extend across the core. Each track end is connected through a metal plated bore hole through the substrates from one track end to the next adjacent track end on the opposite substrate to form a current path circling the core in a toroidal fashion. Indicia are provided on the sensor that define the mechanical axis and the magnetic axis of the sensor.
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: August 3, 2004
    Inventor: John B. Rippingale
  • Patent number: 6760678
    Abstract: A method and system for continuously and automatically calibrating the settings of an electronic compass, as needed, while a vehicle moves from place to place is shown. The calibration technique of the present invention measures the ocal magnetic field while the vehicle moves from place to place and determines points on a reference Cartesian coordinate system. Each such point defines the endpoint for a vector corresponding with the measured field intensity and orientation of the local magnetic field. Any three such points are used to calculate the center of a circle that extends through all of those points. A vector that begins at the origin of the reference Cartesian coordinate system and terminates at the calculated center of the circle is thereafter subtracted from subsequent field measurement vectors that correspond to the field intensity and direction of the local magnetic field.
    Type: Grant
    Filed: April 11, 2000
    Date of Patent: July 6, 2004
    Assignee: Electronics Tomorrow Limited
    Inventors: Patrick Fong Wing Hon, Johnny Tam Ping Wah
  • Patent number: 6643941
    Abstract: The compass system of the present invention utilizes an improved calibration routine in which a processing circuit of the compass recalibrates the compass each time three data points are obtained from a magnetic field sensor that meet predetermined criteria. One such criterion is that the three data points define corners of a triangle that is substantially non-obtuse. When three data points have been obtained that define a triangle meeting this criterion, the processing circuit calculates a center point for a circle upon which all three data points lie by solving the equation 2+y2+Ax+By+C=0 for A, B, and C, using the coordinate values (x,y) for the three data points and defining the center point as (−A/2, −B/2).
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: November 11, 2003
    Assignee: Johnson Controls Technology Company
    Inventors: Jeffrey N. Parks, Thomas R. Olson, David J. Slater
  • Patent number: 6566856
    Abstract: A magnetoresistive sensor system having resistive elements changing in ohmic value in the presence of a magnetic field of a current being measured. The variant values of the elements are amplified by some electronics that inherently add offset to the resultant values. The elements themselves also add an offset. The output of the electronics is modulated and then buffered as an output. This output is demodulated and integrated. The resultant signal is fed back to the input of the electronics to null out the offsets. The output of the buffer also goes to an inductive coil that is magnetically coupled to the resistive elements to null out the magnetic field from the current being measured. The buffer output indicates the magnitude of the current being measured. An oscillator outputs a signal to actuate the modulator and the demodulator. The oscillator signal also goes to a set/reset circuit for setting and resetting the resistive elements of the magnetoresistive sensor.
    Type: Grant
    Filed: June 14, 2002
    Date of Patent: May 20, 2003
    Assignee: Honeywell International Inc.
    Inventors: David A. Sandquist, James E. Lenz, Dale F. Berndt
  • Patent number: 6523271
    Abstract: To reduce a dispersion in a sensitivity of a magnetism detecting circuit driving, by current, a magnetism sensor comprising magnetism resistance elements in a bridge constitution to a dispersion in a sensitivity of a magnetism sensor. An electronic azimuth meter is provided with EEPROM and drive current set values are previously stored to EEPROM. The drive current set values are calculated by a predetermined calculation by measuring bridge resistance of a magnetism sensor of the electronic azimuth meter. In detecting magnetism by the magnetism sensor, CPU controls a sensor drive circuit based on the drive current set values stored to EEPROM. Thereby, the sensor drive circuit supplies a magnetism sensor with optimum drive current in accordance with a bridge resistance value thereof.
    Type: Grant
    Filed: July 20, 2001
    Date of Patent: February 25, 2003
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuo Kato
  • Patent number: 6512370
    Abstract: A low power, frequency-mode magnetometer. The magnetometer includes an LC oscillator, a bias resistor and a polarity switch. The LC oscillator produces an output signal having a variable frequency indicative of both a magnitude and a polarity of a magnetic field. The LC oscillator includes an inverting amplifier and a Pi network including an inductor and two capacitors. The inductor is realized as a coil wound about a high permeability, low hysteresis, core material that has been longitudinally cut. The inductor is coupled between an input node and an output node, as is the inverting amplifier. The inverting amplifier has a first trigger voltage and a second trigger voltage, which are symmetrically located with respect to one half of a DC bias voltage. The bias resistor is coupled between the input node of the LC oscillator and a first node and controls the DC bias current to the inductor. The polarity switch switches the first node between ground and the bias DC voltage.
    Type: Grant
    Filed: February 12, 1999
    Date of Patent: January 28, 2003
    Assignee: Elf Engineering, Ltd.
    Inventor: John James
  • Patent number: 6502014
    Abstract: The present invention relates to a control circuit for controlling the driving stability of a vehicle where the input quantities determining the course of track are input in a vehicle model circuit which determines at least on nominal value for a control quantity subject to parameters memorised in the vehicle reference model on the basis of a vehicle reference model reproducing the characteristics of the vehicle.
    Type: Grant
    Filed: May 2, 2001
    Date of Patent: December 31, 2002
    Assignee: Continental Teves AG & Co., oHG
    Inventors: Torsten Herrmann, Mile Jokic, Ulrich Lüders, Holger Duis, Ralf Endress
  • Patent number: 6466871
    Abstract: A method for calibrating the attitude of a compass in relation to the platform on which the compass is installed. The compass includes an attitude determining device and an optical sighting device and the compass is integrally mounted on a platform. The method includes the steps of determining the angle between the optical sighting device and the attitude determining device, determining the attitude between the optical sighting device and the platform, and determining the attitude between the attitude determining device and the platform.
    Type: Grant
    Filed: October 3, 2000
    Date of Patent: October 15, 2002
    Assignee: Azimuth Technologies
    Inventors: Shlomo Reisman, Boris Bronsteyn
  • Patent number: 6427349
    Abstract: An electronic compass is described for use in vehicles. The compass employs a magnetoresistive sensor for sensing the earth magnetic field and the sensor is operated in alternate set/reset bias modes. In a first embodiment, the compass is provided with deviation compensation by a closed loop system including measurement of the sensor output signals and an offset current strap for nullifying the vehicle deviation field. In a second embodiment, deviation compensation is provided by operation in an initial calibration mode and by operation in a normal compensation mode to adjust compensation, as needed, on a long term basis during normal operation of the compass. In the initial calibration mode, while the vehicle is being driven, the signal peak values are adjusted to a nominal earth field level by changing the offset current. Then, compensating signal reference values for each axis are determined as each peak for that axis is determined.
    Type: Grant
    Filed: January 11, 2001
    Date of Patent: August 6, 2002
    Assignee: Donnelly Corporation
    Inventors: Rodney K. Blank, Richard J. Gahan, Howard J. Haselhuhn, Jr., Kenneth L. Schierbeek, Kenneth Schofield
  • Patent number: 6407547
    Abstract: A biaxial flux gate type magnetic sensor has a core which is made of a magnetic thin film in the shape of a loop, patterned upper and lower electrically conductive thin-film layers respectively above and below this core each with an insulating layer in between, and electrically conductive connecting members each extending between and electrically connecting these upper and lower electrically conductive layers. These upper and lower electrically conductive layers are patterned and the contact portions connect them such that they together provide an excitation coil and four detection coils. These coils are each formed so as to be wound helically and uniformly around and along a circumferential direction of the loop-shaped core by passing both inside and outside the loop. The loop is of a shape which is symmetrical with respect to two mutually perpendicular directions and is divided into four mutually symmetric sections.
    Type: Grant
    Filed: August 31, 1999
    Date of Patent: June 18, 2002
    Assignee: Shimadzu Corporation
    Inventors: Yasuharu Yamada, Kenichi Yoshimi
  • Patent number: 6380735
    Abstract: A magnetic sensor of orthogonal flux-gate type is provided with a cylindrical core made of a soft magnetic material; an internal conductor that is placed inside the core; a detection coil wound up on the core; and an external conductor that is placed around the core and electrically connected to the internal conductor. A high-frequency current is allowed to flow through the internal core so that a magnetic field to be measured which resides around the detection coil is changed and the intensity and direction of the magnetic field to be measured is detected on the basis of an output of the detection coil. Since the external conductor is placed on the periphery of the core, it is possible to prevent the magnetic flux formed by the core from magnetizing any space, and consequently to concentrate the magnetic field on the core.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: April 30, 2002
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventor: Makoto Kawakami
  • Patent number: 6282803
    Abstract: A self calibrating zero compensation circuit for a fluxgate compass comprising a toroidal core; a drive winding coupled to said core, and at least one and preferably two secondary sensing windings coupled to said core comprises a continuously operating demodulator coupled to the sensing windings and an intermittently operated drive signal fed to the drive winding. A microprocessor is coupled to the demodulator output through an analog to digital converter. The microprocessor provides alternatingly to the drive winding a drive signal for a first period of time and prevents transmission of the drive signal for a second, preferably equal period of time. During the second period of time, the sensing windings and the demodulator provide an output signal to said microprocessor representing the zero signal reference. The demodulator output during the first period of time represents the magnetic field signal from the compass.
    Type: Grant
    Filed: April 24, 1998
    Date of Patent: September 4, 2001
    Assignee: Laser Technology, Inc.
    Inventor: Jeremy G. Dunne
  • Patent number: 6222363
    Abstract: A flux gate inductor responsive to an external magnetic field produced by a rotating magnetoelastic sleeve and oscillating voltage applied to the flux gate inductor induces a field in the flux gate inductor, for inducing current flow through the flux gate inductor, which flows through a shunting resistor, creating a voltage which is triangular as a result of the inductance of the flux gate. The sum of the induced and external fields exceeds the saturation flux density of the flux gate, causing the flux gate inductance to zero. This results in a rise in the current through the flux gate inductor and a voltage spike across the shunt resistor. The spike is detected for causing a change in an inverter for producing the oscillation voltage. Meanwhile, the external magnetic field causes an asymmetry between positive, negative currents required to saturate the flux gate inductor. This asymmetry results in a departure of the oscillation voltage from a 50% duty cycle.
    Type: Grant
    Filed: January 8, 1999
    Date of Patent: April 24, 2001
    Assignee: Methode Electronics, Inc.
    Inventor: David W. Cripe
  • Patent number: 6218831
    Abstract: The present invention is a system for cyclically driving an electrical current through at least one non-linear (i.e., saturable) inductor in alternating directions so as to produce a substantially periodic current waveform, and for producing an output signal representative of the current waveform. The system includes at least one capacitive node electrically coupled between a voltage source and a system ground, for storing electrical energy provided by the voltages source. The energy stored within the system is transferred as electrical current in alternating directions through the inductor via a switching network and a controller for configuring the switching network. The controller allows current to flow in each direction until the inductor saturates.
    Type: Grant
    Filed: May 19, 1999
    Date of Patent: April 17, 2001
    Assignee: Arthur D. Little, Inc.
    Inventor: J. Thomas Fowler
  • Patent number: 6181130
    Abstract: A magnetic sensor includes a bobbin having one surface provided with a toroidal groove, and a toroidal inductor accommodated in the groove. The toroidal inductor has a toroidal core and an excitation coil wound on the toroidal core. The excitation coil has a conductive pattern of a plurality of thin-film linear conductors individually extending in a radial direction on a surface of the bobbin and on inner side and bottom surfaces of the toroidal groove with a predetermined angular space, a toroidal core received in the groove, and a plurality of connecting wires each of which is bridged over the toroidal groove and toroidal core to interconnect an inner end of one of the thin-film linear conductors and an outer end of a next adjacent one of the thin-film linear conductors. The conductive pattern and the connecting wires form the excitation coil wound around the toroidal core. Thus, the toroidal inductor is formed in the toroidal groove.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: January 30, 2001
    Assignee: Tokin Corporation
    Inventors: Norimitsu Hoshi, Naoyuki Sato
  • Patent number: 6173501
    Abstract: An electronic compass is described for use in vehicles. The compass employs a magnetoresistive sensor for sensing the earth magnetic field and the sensor is operated in alternate set/reset bias modes. In a first embodiment, the compass is provided with deviation compensation by a closed loop system including measurement of the sensor output signals and an offset current strap for nullifying the vehicle deviation field. In a second embodiment, deviation compensation is provided by operation in an initial calibration mode and by operation in a normal compensation mode to adjust compensation, as needed, on a long term basis during normal operation of the compass. In the initial calibration mode, while the vehicle is being driven, the signal peak values are adjusted to a nominal earth field level by changing the offset current. Then, compensating signal reference values for each axis are determined as each peak for that axis is determined.
    Type: Grant
    Filed: September 8, 1998
    Date of Patent: January 16, 2001
    Assignee: Donnelly Corporation
    Inventors: Rodney K. Blank, Richard J. Gahan, Howard J. Haselhuhn, Jr., Kenneth L. Schierbeek, Kenneth Schofield
  • Patent number: 6141881
    Abstract: An compass having an electronic magnetic field sensor and an analog directional display is disclosed wherein a signal from the field sensor proportional to one component of the earth's magnetic field is alternated in polarity and integrated to produce a triangular waveform the frequency of which is proportional to the strength of that field component and wherein a triangular waveform having a frequency proportional to the second component of the earth's magnetic field is produced in the same manner. These values are used by a microcontroller to control an air-core gauge such that a disk with reference markings attached to the gauge remains positioned with one of the reference markings facing either magnetic or true north. A resistor ladder network is also connected in parallel to the inputs of the integrators and controlled by the microprocessor through a shift register in order keep the integrators out of saturation.
    Type: Grant
    Filed: November 3, 1998
    Date of Patent: November 7, 2000
    Assignee: Invotronics Manufacturing
    Inventors: Craig A. Ayres, John A. Ayres, Douglas Hall
  • Patent number: 6084406
    Abstract: A magnetic field sensor element comprises an elongated core of high-magnetic permeability material having a coil of electrically-conductive wire wound around and along a central axis of the core. The sensor, due to inductance of the core which changes with application of a local magnetic field, exhibits a characteristic of delaying an electrical input as a function of the strength of a magnetic field in the direction of the axis of the core, and the delay is measured as a function of the strength of the magnetic field. Appropriate circuitry provides at least one step-function voltage input to the coil such that the resulting delay in current charge-up into the coil creates a voltage across the coil which decays to a known reference value. The time delay for the voltage decaying to the reference value varies as a monotonic function with the strength of the applied magnetic field to be measured.
    Type: Grant
    Filed: April 1, 1997
    Date of Patent: July 4, 2000
    Assignee: Precision Navigation, Inc.
    Inventors: John J. James, George Hsu
  • Patent number: 6070333
    Abstract: An electronic compass has a compass housing. An electronic magnetic field sensor is disposed in a fixed position relative to the compass housing. A magnet is rotatably mounted relative to the magnetic field sensor and independently aligned with a terrestrial magnetic field. The magnet has a magnetic field with a magnetic field direction and the electronic magnetic field sensor is located within a range of influence of the magnetic field. The electronic magnetic field sensor has a first magnetoresistor with a first fixed reference axis and an electric resistance of the first magnetoresistor is a function of a first angle of rotation between the fixed first reference axis and the direction of the magnetic field. The electronic magnetic field sensor defines a first differential bridge circuit and the first magnetoresistor is disposed in the first differential bridge circuit which during operation of the compass, supplies an output voltage dependent on the first angle of rotation.
    Type: Grant
    Filed: January 26, 1998
    Date of Patent: June 6, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventors: Michael Kutzner, Erich Hufgard