Patents by Inventor Hiraku Hirabayashi

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

  • Publication number: 20190162609
    Abstract: An operation processing apparatus that calculates a rotation angle based on a first output signal and a second output signal, which differ in signal frequency from each other, is provided with a first cross-coupled operation part that performs a first cross-coupled operation and a second cross-coupled operation part that performs a second cross-coupled operation based on the first and second output signals. A first Lissajous curve generation part generates a first Lissajous curve based on the result of operation by the first cross-coupled operation part, and a second Lissajous curve generation part generates a second Lissajous curve based on the result of operation by the second cross-coupled operation part. A rotation angle computing part calculates the rotation angle based on the first Lissajous curve and the second Lissajous curve.
    Type: Application
    Filed: October 17, 2018
    Publication date: May 30, 2019
    Inventors: Shinichirou MOCHIZUKI, Hiraku HIRABAYASHI
  • Publication number: 20190128698
    Abstract: A position detection device includes a first position detector, a second position detector, and a signal generator. The first position detector includes a first magnetic field generation unit, a second magnetic field generation unit, and a first magnetic sensor. The second position detector includes a third magnetic field generation unit, a fourth magnetic field generation unit, and a second magnetic sensor. The positions of the second and fourth magnetic field generation units vary in response to variations in a detection-target position. The signal generator generates a position detection signal, which is the sum of a first detection signal generated by the first magnetic sensor and a second detection signal generated by the second magnetic sensor. Each of the first and second position detectors includes a bias magnetic field generation unit.
    Type: Application
    Filed: August 30, 2018
    Publication date: May 2, 2019
    Applicant: TDK CORPORATION
    Inventors: Tsuyoshi UMEHARA, Hayato MIYASHITA, Keisuke UCHIDA, Hiraku HIRABAYASHI
  • Publication number: 20190128699
    Abstract: A position detection device includes a first magnetic field generation unit for generating a first magnetic field, a second magnetic field generation unit for generating a second magnetic field, and a magnetic sensor. The position of the second magnetic field generation unit relative to the first magnetic field generation unit is variable. The magnetic sensor detects the direction of a target magnetic field at a detection position in a reference plane. The target magnetic field is a composite magnetic field of first and second magnetic field components which are respective components of the first and second magnetic fields parallel to the reference plane. The magnetic sensor includes a magnetoresistive element including a free layer and a magnetization pinned layer. In the reference plane, two directions orthogonal to the magnetization direction of the magnetization pinned layer are each different from both of directions of the first and second magnetic field components.
    Type: Application
    Filed: September 6, 2018
    Publication date: May 2, 2019
    Applicant: TDK CORPORATION
    Inventors: Keisuke UCHIDA, Tsuyoshi UMEHARA, Toshihide SUTO, Hiraku HIRABAYASHI
  • Patent number: 10254135
    Abstract: A correction apparatus for an angle sensor includes a correction information generator for generating correction information, and a correction processing unit for performing correction processing in the course of generation of a detected angle value by an angle detector. Details of the correction processing are determined on the basis of the correction information. The correction information generator includes an error estimate generation unit and a correction information determination unit. The error estimate generation unit generates, on the basis of a first signal and a second signal, an error estimate containing a variable component that varies depending on an ideal angle estimate. The correction information determination unit determines the correction information on the basis of the error estimate.
    Type: Grant
    Filed: June 14, 2016
    Date of Patent: April 9, 2019
    Assignee: TDK CORPORATION
    Inventors: Shinichirou Mochizuki, Hiraku Hirabayashi, Hiroshi Naganuma, Tsuyoshi Umehara, Yuichiro Yamaji
  • Publication number: 20190033347
    Abstract: An offset estimation unit determines an estimate of an offset of a detection value to be output from a magnetic sensor. The offset estimation unit includes an initial function storing unit, a function settlement unit, and an estimate determination unit. The initial function storing unit stores an initial function for determining the estimate according to a first variable and a second variable, with a reference offset as the first variable and temperature as the second variable, the reference offset being the offset at a reference temperature. The function settlement unit settles a value of the first variable of the initial function by the reference offset, and turns the initial function into an estimate determination function for determining the estimate according to a value of the second variable. The estimate determination unit determines the estimate by settling the value of the second variable of the estimate determination function by temperature information.
    Type: Application
    Filed: June 13, 2018
    Publication date: January 31, 2019
    Applicant: TDK CORPORATION
    Inventors: Kenichi TAKANO, Yuta SAITO, Hiraku HIRABAYASHI
  • Publication number: 20180356473
    Abstract: A pair of bias magnets applies a bias magnetic field to the magneto-resistive effect element, the bias magnetic field having a component in a direction such that the component cancels the external magnetic field that is applied to the magneto-resistive effect element and a component that is perpendicular to the external magnetic field. The bias magnet has an elongate cross section in a plane that is parallel both to the external magnetic field and to the bias magnetic field. In a projection plane that is parallel to the cross section and onto which the bias magnets and the magneto-resistive effect element are projected, the bias magnet includes an element facing side that is opposite to the magneto-resistive effect element and that extends in a longitudinal direction. The bias magnet is magnetized in a direction that is perpendicular to the longitudinal direction. The element facing side is longer than other sides.
    Type: Application
    Filed: May 30, 2018
    Publication date: December 13, 2018
    Inventors: Yohei HIROTA, Hayato MIYASHITA, Tsuyoshi UMEHARA, Hiraku HIRABAYASHI
  • Publication number: 20180356448
    Abstract: A current sensor has: a magneto-resistive effect element which is arranged near a current line, to which a signal magnetic field is applied, the signal magnetic field being is induced by a current that flows in the current line, and which generates a magneto-resistive change in accordance with a change of the signal magnetic field; cancelling magnetic field generating means that is provided near the magneto-resistive effect element and that generates a cancelling magnetic field that cancels the signal magnetic field; a first soft magnetic body that is provided between the magneto-resistive effect element and the current line; and a pair of second soft magnetic bodies that are provided on both sides of the magneto-resistive effect element with regard to a magnetization detecting direction of the magneto-resistive effect element.
    Type: Application
    Filed: June 5, 2018
    Publication date: December 13, 2018
    Inventors: Yuta Saito, Kenichi Takano, Hiraku Hirabayashi
  • Publication number: 20180275204
    Abstract: A magnetic sensor device comprises a magnetic sensor chip that has a substantially rectangular shape and that contains a magnetic sensor element; and a sealing body, which is composed of a resin material containing magnetic particles and that integrally seals the chip. The chip includes a first and second side surfaces which are mutually opposite to each other, and a third and fourth side surfaces which are mutually opposite to each other and orthogonal to the first and second side surfaces. The sealing body contains first to forth sealing parts. The thicknesses of the first and second sealing parts are smaller than the particle diameter of the particles, and the thickness of at least the third sealing part is larger than the particle diameter of the particles. The particles exist in at least the third sealing part and substantially do not exist in the first and second sealing parts.
    Type: Application
    Filed: March 15, 2018
    Publication date: September 27, 2018
    Inventors: Kunihiro Ueda, Koichi Otani, Hiraku Hirabayashi, Shuhei Miyazaki
  • Publication number: 20180274898
    Abstract: An angle sensor system includes a magnetic field generation unit for generating a rotating magnetic field, and an angle sensor for detecting the rotating magnetic field to generate a detected angle value. The rotating magnetic field contains first and second magnetic field components orthogonal to each other. Each of the first and second magnetic field components contains an ideal magnetic field component and an error magnetic field component. The error magnetic field component causes an angular error that varies with ½ the predetermined period. The angle sensor includes first and second detection signal generation units. Each of the first and second detection signal generation units includes a magnetic layer whose magnetization direction varies according to the direction of the rotating magnetic field. The magnetic layer is provided with a magnetic anisotropy that is set to reduce the angular error resulting from the error magnetic field component.
    Type: Application
    Filed: January 30, 2018
    Publication date: September 27, 2018
    Applicant: TDK Corporation
    Inventors: Keisuke UCHIDA, Hiraku HIRABAYASHI
  • Publication number: 20180274897
    Abstract: An angle sensor system includes a magnetic field generation unit for generating a rotating magnetic field, and an angle sensor for detecting the rotating magnetic field to generate a detected angle value. The rotating magnetic field contains first and second magnetic field components orthogonal to each other. Each of the first and second magnetic field components contains an ideal magnetic field component, and an error component corresponding to the fifth harmonic of the ideal magnetic field component. The angle sensor includes first and second detection signal generation units. Each of the first and second detection signal generation units includes a magnetic layer whose magnetization direction varies according to the direction of the rotating magnetic field. The magnetic layer is provided with a magnetic anisotropy that is set to reduce an angular error resulting from the error components of the first and second magnetic field components.
    Type: Application
    Filed: January 29, 2018
    Publication date: September 27, 2018
    Applicant: TDK CORPORATION
    Inventors: Keisuke UCHIDA, Hiraku HIRABAYASHI
  • Publication number: 20180274945
    Abstract: A position detection device includes a first magnetic field generation unit for generating a first magnetic field, a second magnetic field generation unit for generating a second magnetic field, and a magnetic sensor. The relative position of the second magnetic field generation unit with respect to the first magnetic field generation unit is variable. The magnetic sensor detects a composite magnetic field of the first and second magnetic fields, and generates a detection signal corresponding to the direction of the detected magnetic field. Varying the relative position of the second magnetic field generation unit with respect to the first magnetic field generation unit varies the strength of the second magnetic field at the detection position. At the detection position, a relative angle formed by the direction of the second magnetic field with the direction of the first magnetic field is greater than 90° and smaller than 180°.
    Type: Application
    Filed: February 9, 2018
    Publication date: September 27, 2018
    Applicant: TDK CORPORATION
    Inventors: Keisuke UCHIDA, Hiraku HIRABAYASHI
  • Publication number: 20180275215
    Abstract: The magnetic sensor can prevent an increase of a positional detection error of a subject/object even in the case of applying an external magnetic field with a magnetic field intensity exceeding a predetermined range. A magnetic sensor is equipped with a magnetoresistive effect element (MR element) 11 that can detect an external magnetic field and a soft magnetic body shield 12. The soft magnetic body shield(s) 12 are/is positioned above and/or below the MR element 11 in a side view, and the size of the MR element 11 is physically included within a perimeter of the soft magnetic body shield 12.
    Type: Application
    Filed: November 29, 2017
    Publication date: September 27, 2018
    Inventors: Keisuke UCHIDA, Hiraku HIRABAYASHI
  • Publication number: 20180275217
    Abstract: A magnetic sensor includes a magnetic field conversion unit and a magnetic field detection unit. The magnetic field conversion unit receives an input magnetic field containing an input magnetic field component in a direction parallel to Z direction, and generates an output magnetic field containing an output magnetic field component in a direction parallel to X direction. The magnetic field detection unit receives the output magmetic field and generates an output signal corresponding to the input magnetic field component. The magnetic field detection unit includes first and second magnetic detection elements. When misalignment occurs between the magnetic field conversion unit and the magnetic field detection unit, one of the strength of a portion of the output magnetic field component that the first magnetic detection element receives and the strength of a portion of the output magnetic field component that the second magnetic detection element receives increases while the other decreases.
    Type: Application
    Filed: February 8, 2018
    Publication date: September 27, 2018
    Applicant: TDK CORPORATION
    Inventors: Keisuke UCHIDA, Kenzo MAKINO, Hiraku HIRABAYASHI
  • Publication number: 20180261760
    Abstract: A magnetic sensor is provided which can improve density of magnetoresistance effect elements without narrowing the wiring pitch. A plurality of element array layers 10 are stacked one on another, each of the element array layers including a plurality of magnetoresistance effect elements 1 arranged in parallel in an in-plane direction, and magnetoresistance effect elements 1 in the plurality of element array layers 10 are connected in series to each other.
    Type: Application
    Filed: December 8, 2017
    Publication date: September 13, 2018
    Inventors: Tetsuya HIRAKI, Naoki OHTA, Hiraku HIRABAYASHI, Yoshiaki TANAKA
  • Publication number: 20180254686
    Abstract: A magnetic sensor includes a magnetic detection element circuit that includes first and second magnetic detection elements, which are connected in series, and an output terminal, which is positioned between the first and second magnetic detection elements; an impedance matching device, which has a prescribed input voltage range and is connected to an output terminal of the magnetic detection element circuit; a first current supply source, which supplies an electric current to the magnetic detection element circuit; and a second current supply source, which supplies an electric current to the impedance matching device. A resistor is provided between the output terminal of the magnetic detection element circuit and the first current supply source and/or a reference electric potential point.
    Type: Application
    Filed: December 5, 2017
    Publication date: September 6, 2018
    Inventors: Yosuke Komasaki, Naoki Ohta, Hayato Miyashita, Takakazu Imai, Hiraku Hirabayashi, Masanori Sakai, Satoshi Abe, Tsuyoshi Umehara
  • Patent number: 10006789
    Abstract: A correction apparatus for an angle sensor includes a correction unit for performing first correction processing on a first detection signal and performing second correction processing on a second detection signal. The first correction processing is processing for combining the first detection signal and a first correction value to generate a first corrected detection signal. The second correction processing is processing for combining the second detection signal and a second correction value to generate a second corrected detection signal. The first correction value has a first amplitude and varies with a first period. The second correction value has a second amplitude and varies with a second period. The first and second amplitudes are of the same value. The first and second periods are of the same value equal to ? or ? of the period of an ideal component of each of the first and second detection signals.
    Type: Grant
    Filed: March 10, 2017
    Date of Patent: June 26, 2018
    Assignee: TDK CORPORATION
    Inventors: Shinichirou Mochizuki, Hiraku Hirabayashi, Tsuyoshi Umehara, Hiroshi Naganuma, Kazuya Watanabe
  • Publication number: 20180172782
    Abstract: A magnetic field detection device includes a first soft magnetic body, a second soft magnetic body, and a magnetism detection element. The first soft magnetic body extends to have a first length in a first direction, and has a first width, smaller than the first length, in a second direction. The second direction is substantially orthogonal to the first direction. The second soft magnetic body is disposed to be spaced apart from and face the first soft magnetic body in the first direction, extends to have a second length in the first direction, and has a second width, smaller than the second length, in the second direction. The magnetism detection element is disposed, in the first direction, between the first and second soft magnetic bodies, and extends to have a third length in the first direction and a third width, larger than the third length, in the second direction.
    Type: Application
    Filed: September 25, 2017
    Publication date: June 21, 2018
    Applicant: TDK CORPORATION
    Inventors: Masaki NAGATA, Kazuya WATANABE, Keisuke UCHIDA, Kohei HONMA, Hiraku HIRABAYASHI
  • Publication number: 20180164127
    Abstract: An angle sensor includes a plurality of composite magnetic field information generation units and an angle computing unit. The plurality of composite magnetic field information generation units detect, at a plurality of detection positions, a composite magnetic field of a magnetic field to be detected and a noise magnetic field other than the magnetic field to be detected, and thereby generate a plurality of pieces of composite magnetic field information including information on at least the direction, out of the direction and the strength, of the composite magnetic field. At each of the plurality of detection positions, the magnetic field to be detected varies in direction according to an angle to be detected. The angle computing unit generates a detected angle value using the method of least squares on the basis of the plurality of pieces of composite magnetic field information.
    Type: Application
    Filed: November 7, 2017
    Publication date: June 14, 2018
    Applicant: TDK CORPORATION
    Inventors: Kenkichi ANAGAWA, Shinichirou MOCHIZUKI, Hiraku HIRABAYASHI, Kazuya WATANABE
  • Publication number: 20180156874
    Abstract: Provided is a magnetic field detection device that includes a first soft magnetic body and a magnetic detector. The first soft magnetic body includes a first plate and a first protrusion. The first plate includes a first surface including a first outer edge. The first protrusion is provided at a first arrangement position in the first surface and includes a first tip on opposite side to the first surface. The first arrangement position is set back from the first outer edge. The magnetic detector is provided in the vicinity of the first tip.
    Type: Application
    Filed: August 25, 2017
    Publication date: June 7, 2018
    Applicant: TDK CORPORATION
    Inventors: Masaki NAGATA, Kazuya WATANABE, Keisuke UCHIDA, Kohei HONMA, Hiraku HIRABAYASHI
  • Publication number: 20180113176
    Abstract: Provided is a magnetic field detection device that includes a first and second soft magnetic bodies, and a magnetic detector. The first and second soft magnetic bodies extend along a first plane and are disposed in confronted relation in a third direction. The first plane includes both a first direction and a second direction orthogonal to the first direction. The third direction is orthogonal to both the first and second directions. The magnetic detector is provided between the first and second soft magnetic bodies in the third direction.
    Type: Application
    Filed: August 28, 2017
    Publication date: April 26, 2018
    Applicant: TDK CORPORATION
    Inventors: Masaki NAGATA, Kazuya WATANABE, Keisuke UCHIDA, Kohei HONMA, Hiraku HIRABAYASHI