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).

  • Patent number: 11598653
    Abstract: A rotational angle detection apparatus is provided with a magnet disposed so as to be rotatable integrally with an axis of rotation, having a substantially circular shape when viewed along the axis of rotation, and including a magnetization vector component in a direction orthogonal to the axis of rotation; a magnetic sensor that outputs a sensor signal on the basis of change in a magnetic field accompanying rotation of the magnet; and a rotational angle detector that detects a rotational angle of the rotating body on the basis of the sensor signal output by the magnetic sensor; wherein the magnet has a curved inclined surface with a concave shape along the axis of rotation from a prescribed position on the outer side in a radial direction toward the axis of rotation, and when a circular virtual plane orthogonal to the axis of rotation and centered at the axis of rotation is established at a position opposed to the curved inclined surface, the magnetic sensor is disposed at a position at which the amplitudes
    Type: Grant
    Filed: May 26, 2022
    Date of Patent: March 7, 2023
    Assignee: TDK Corporation
    Inventors: Masaki Nagata, Kazuya Watanabe, Hiraku Hirabayashi
  • Publication number: 20230052013
    Abstract: A magnetic sensor comprises a magnetoresistive effect element including a first side surface and a second side surface facing in opposite directions along a first axis and a first end surface and a second end surface facing in opposite directions along a second axis substantially orthogonal to the first axis. The sensor has a sensitivity axis extending in a direction of the first axis, a first yoke unit provided adjacent to the first side surface of the magnetoresistive effect element, and a first bias magnetic field generation unit provided adjacent to the first end surface of the magnetoresistive effect element. The first bias magnetic field generation unit is provided to be capable of applying a bias magnetic field on the magnetoresistive effect element and the first yoke unit.
    Type: Application
    Filed: October 24, 2022
    Publication date: February 16, 2023
    Inventors: Kenichi TAKANO, Tsuyoshi UMEHARA, Yuta SAITO, Hiraku HIRABAYASHI
  • Patent number: 11579213
    Abstract: A magnetic sensor whose output characteristic is less sensitive to the environmental temperature is provided. Magnetic sensor 1 has free layer 24 whose magnetization direction changes in response to an external magnetic field, pinned layer 22 whose magnetization direction is fixed with respect to the external magnetic field, spacer layer 23 that is located between pinned layer 22 and free layer 24 and that exhibits a magnetoresistance effect, and at least one magnet film 25 that applies a bias magnetic field to free layer 24. The film thickness of the magnet film is 15 nm or more and 50 nm or less. The relationship of 0.7?TC_HM/TC_FL?1.05 is satisfied, where TC_HM is Curie temperature of the magnet film, and TC_FL is Curie temperature of the free layer.
    Type: Grant
    Filed: March 18, 2021
    Date of Patent: February 14, 2023
    Assignee: TDK Corporation
    Inventors: Kenichi Takano, Yuta Saito, Hiraku Hirabayashi
  • Publication number: 20230008088
    Abstract: A magnetic sensor device includes at least one magnetic sensor and a support. A center of gravity of an element layout area of the at least one magnetic sensor is deviated from a center of gravity of a reference plane of the support. The at least one magnetic sensor includes four resistor sections constituted by a plurality of magnetoresistive elements. Magnetization of a free layer in each of two of the resistor sections includes a component in a third magnetization direction. The magnetization of a free layer in each of the other two resistor sections includes a component in a fourth magnetization direction opposite to the third magnetization direction.
    Type: Application
    Filed: May 2, 2022
    Publication date: January 12, 2023
    Applicant: TDK CORPORATION
    Inventors: Norikazu OTA, Hiraku HIRABAYASHI, Kazuma YAMAWAKI, Shuhei MIYAZAKI, Kazuya WATANABE
  • Patent number: 11553132
    Abstract: The position detecting device of the present invention is a device for detecting the position of a movable detection target within a predetermined movable range. The position detecting device comprises: a first magnet (13A) and a second magnet (13B) which are arranged so as to move integrally with the movement of the detection target; a first magnetic detecting circuit (20A) that detects the magnetic field of the first magnet (13A) and a second magnetic detecting circuit (20B) that detects the magnetic field of the second magnet (13B), which are arranged at positions outside the movable range; and a differential amplifier (8) that amplifies the difference between the detection signals of the magnetic field output from the first magnetic detecting circuit (20A) and the second magnetic detecting circuit (20B), and that outputs the amplified difference of the signal as a position detecting signal of the detection target.
    Type: Grant
    Filed: December 18, 2020
    Date of Patent: January 10, 2023
    Assignee: TDK Corporation
    Inventors: Yongfu Cai, Hiraku Hirabayashi, Shusuke Ichihashi
  • Patent number: 11549970
    Abstract: A magnetic field detection apparatus includes a magnetoresistive effect element and a helical coil. The magnetoresistive effect element includes a magnetoresistive effect film extending in a first axis direction. The helical coil includes a parallel connection including first and second parts extending in a second axis direction inclined with respect to the first axis direction. The first and second parts are adjacent to each other in a third axis direction and coupled to each other in parallel. The helical coil is wound around the magnetoresistive effect element while extending along the third axis direction. The magnetoresistive effect film overlaps the first and second parts in a fourth axis direction orthogonal to the second and third axis directions. The helical coil is configured to be supplied with a current and thereby configured to generate an induction magnetic field to be applied to the magnetoresistive effect film in the third axis direction.
    Type: Grant
    Filed: October 27, 2020
    Date of Patent: January 10, 2023
    Assignee: TDK CORPORATION
    Inventors: Norikazu Ota, Kenzo Makino, Hiraku Hirabayashi
  • Patent number: 11531071
    Abstract: A magnetic field detection device of an embodiment of the disclosure includes: a first magnetic field detection element having a first resistance value increasing upon application of a first magnetic field in a first direction and decreasing upon application of a second magnetic field in a second direction; and a second magnetic field detection element having a second resistance value decreasing upon application of the first magnetic field and increasing upon application of the second magnetic field. The first and second magnetic field detection elements each include first and second magneto-resistive effect films coupled in series. The first magneto-resistive effect film has a first major-axis direction inclined at a first inclination angle relative to the first direction. The second magneto-resistive effect film has a second major-axis direction inclined at a second inclination angle relative to the first direction. The magnetic field detection device satisfies conditional expressions (1) and (2).
    Type: Grant
    Filed: April 12, 2021
    Date of Patent: December 20, 2022
    Assignee: TDK CORPORATION
    Inventors: Kenichi Takano, Hiraku Hirabayashi, Yuta Saito
  • Patent number: 11519978
    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: Grant
    Filed: March 25, 2021
    Date of Patent: December 6, 2022
    Assignee: TDK Corporation
    Inventors: Yohei Hirota, Hayato Miyashita, Tsuyoshi Umehara, Hiraku Hirabayashi
  • Patent number: 11506733
    Abstract: A magnetic sensor comprises a magnetoresistive effect element including a first side surface and a second side surface facing in opposite directions along a first axis and a first end surface and a second end surface facing in opposite directions along a second axis substantially orthogonal to the first axis. The sensor has a sensitivity axis extending in a direction of the first axis, a first yoke unit provided adjacent to the first side surface of the magnetoresistive effect element, and a first bias magnetic field generation unit provided adjacent to the first end surface of the magnetoresistive effect element. The first bias magnetic field generation unit is provided to be capable of applying a bias magnetic field on the magnetoresistive effect element and the first yoke unit.
    Type: Grant
    Filed: June 17, 2021
    Date of Patent: November 22, 2022
    Assignee: TDK Corporation
    Inventors: Kenichi Takano, Tsuyoshi Umehara, Yuta Saito, Hiraku Hirabayashi
  • Publication number: 20220333953
    Abstract: A magnetic sensor includes first to fourth resistors, a power supply port, a ground port, a first output port, and a second output port. The first resistor and the second resistor are located in a first region and connected in series via a first connection point connected to the first output port. The third resistor and the fourth resistor are located in a second region and connected in series via a second connection point connected to the second output port, at least a part of the second region being located at a position different from the first region in a direction parallel to an X direction. The first and second resistors are located between the third and fourth resistors in a direction parallel to a Y direction.
    Type: Application
    Filed: April 5, 2022
    Publication date: October 20, 2022
    Applicant: TDK CORPORATION
    Inventors: Tsuyoshi UMEHARA, Hiraku HIRABAYASHI, Yongfu CAI
  • Publication number: 20220326320
    Abstract: A magnetic sensor includes a magnetic sensor chip that includes a magnetoresistive effect element and a sealed part. The magnetoresistive effect element includes a free layer and a pinned layer. The sealed part has a first surface and a second surface, which is opposite the first surface. The shape of the sealed part in the plan view from the first surface side is substantially quadrilateral. The substantially quadrilateral shape has a first side and a second side, which are substantially parallel to each other. In the plan view, from the first surface side of the sealed part, the magnetization direction of the pinned layer, in a state in which the external magnetic field is not applied on the magnetoresistive effect element, is inclined with respect to an approximately straight line found through the least squares method using a plurality of points arbitrarily set on the first side.
    Type: Application
    Filed: June 27, 2022
    Publication date: October 13, 2022
    Inventors: Yuta SAITO, Hiraku HIRABAYASHI, Yoshihiro KUDO
  • Publication number: 20220308095
    Abstract: A magnetic field detection apparatus includes a magnetoresistive effect element and a conductor. The magnetoresistive effect element includes a magnetoresistive effect film extending in a first axis direction and including a first end part, a second end part, and an intermediate part between the first and second end parts. The conductor includes a first part and a second part that each extend in a second axis direction inclined with respect to the first axis direction. The conductor is configured to be supplied with a current and thereby configured to generate an induction magnetic field to be applied to the magnetoresistive effect film in a third axis direction orthogonal to the second axis direction. The first part and the second part respectively overlap the first end part and the second end part in a fourth axis direction orthogonal to both of the second axis direction and the third axis direction.
    Type: Application
    Filed: May 26, 2022
    Publication date: September 29, 2022
    Applicant: TDK CORPORATION
    Inventors: Norikazu OTA, Kenzo MAKINO, Hiraku HIRABAYASHI
  • Publication number: 20220299582
    Abstract: At a reference position within a first plane, a magnetic field to be detected has a first direction that changes within the first plane. A magnetic sensor includes an MR element. The MR element includes a magnetic layer having first magnetization that can change in direction within a second plane. The first plane and the second plane intersect at a dihedral angle ? other than 90°. The magnetic field to be detected can be divided into an in-plane component parallel to the second plane and a perpendicular component perpendicular to the second plane. The in-plane component has a second direction that changes with a change in the first direction. The direction of the first magnetization changes with a change in the second direction. A detection value depends on the direction of the first magnetization.
    Type: Application
    Filed: June 9, 2022
    Publication date: September 22, 2022
    Applicant: TDK CORPORATION
    Inventors: Shunji SARUKI, Hiraku HIRABAYASHI, Masanori SAKAI
  • Publication number: 20220282996
    Abstract: A rotational angle detection apparatus is provided with a magnet disposed so as to be rotatable integrally with an axis of rotation, having a substantially circular shape when viewed along the axis of rotation, and including a magnetization vector component in a direction orthogonal to the axis of rotation; a magnetic sensor that outputs a sensor signal on the basis of change in a magnetic field accompanying rotation of the magnet; and a rotational angle detector that detects a rotational angle of the rotating body on the basis of the sensor signal output by the magnetic sensor; wherein the magnet has a curved inclined surface with a concave shape along the axis of rotation from a prescribed position on the outer side in a radial direction toward the axis of rotation, and when a circular virtual plane orthogonal to the axis of rotation and centered at the axis of rotation is established at a position opposed to the curved inclined surface, the magnetic sensor is disposed at a position at which the amplitudes
    Type: Application
    Filed: May 26, 2022
    Publication date: September 8, 2022
    Inventors: Masaki NAGATA, Kazuya WATANABE, Hiraku HIRABAYASHI
  • Publication number: 20220283201
    Abstract: A magnetic sensor device includes a first detection circuit that generates a first detection signal, a coil through which a feedback current is passed to generate a cancellation magnetic field, a second detection circuit that generates a second detection signal having a correspondence with a value of the feedback current, and a control circuit that controls the feedback current. In a closed-loop operation, the control circuit controls the feedback current so that the first detection signal has a constant value. In an open-loop operation, the control circuit maintains the feedback current at a constant value.
    Type: Application
    Filed: November 30, 2021
    Publication date: September 8, 2022
    Applicant: TDK CORPORATION
    Inventors: Yuta SAITO, Hiraku HIRABAYASHI
  • Publication number: 20220268564
    Abstract: A magnetic field generator generates a detection-target magnetic field related to an angle to be detected. An angle sensor includes a first and a second magnetic sensor and a processor. The first magnetic sensor detects, at a first detection position, a first applied magnetic field including the detection-target magnetic field, and generates first detection information having a correspondence with the angle to be detected. The second magnetic sensor detects, at a second detection position, a second applied magnetic field including the detection-target magnetic field, and generates second detection information having a correspondence with the angle to be detected. The processor generates an angle detection value by performing arithmetic processing using the first and second detection information. The ratio of a strength of the detection-target magnetic field at the second detection position to a strength of the detection-target magnetic field at the first detection position is 1.65 or more.
    Type: Application
    Filed: May 16, 2022
    Publication date: August 25, 2022
    Applicant: TDK CORPORATION
    Inventors: Yongfu CAI, Hiraku HIRABAYASHI
  • Publication number: 20220252681
    Abstract: A magnetic field detection device, containing a) a first soft magnetic body containing a1) a first plate including a first surface having a first outer edge; and a2) a first protrusion disposed directly or indirectly on the first surface of the first plate at a first arrangement position set back from the first outer edge, the first protrusion including a first tip on an opposite side to the first surface; and b) a magnetic detector provided in a vicinity of the first tip, wherein the magnetic detector has a magnetic sensing direction along the first surface, and the first protrusion is capable of bending a direction of a first magnetic flux, which comes into the first plate, along the first surface.
    Type: Application
    Filed: April 26, 2022
    Publication date: August 11, 2022
    Applicant: TDK CORPORATION
    Inventors: Masaki NAGATA, Kazuya WATANABE, Keisuke UCHIDA, Kohei HONMA, Hiraku HIRABAYASHI
  • Publication number: 20220244321
    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: April 18, 2022
    Publication date: August 4, 2022
    Applicant: TDK CORPORATION
    Inventors: Masaki NAGATA, Kazuya WATANABE, Keisuke UCHIDA, Kohei HONMA, Hiraku HIRABAYASHI
  • Patent number: 11391795
    Abstract: At a reference position within a first plane, a magnetic field to be detected has a first direction that changes within the first plane. A magnetic sensor includes an MR element. The MR element includes a magnetic layer having first magnetization that can change in direction within a second plane. The first plane and the second plane intersect at a dihedral angle ? other than 90°. The magnetic field to be detected can be divided into an in-plane component parallel to the second plane and a perpendicular component perpendicular to the second plane. The in-plane component has a second direction that changes with a change in the first direction. The direction of the first magnetization changes with a change in the second direction. A detection value depends on the direction of the first magnetization.
    Type: Grant
    Filed: May 19, 2020
    Date of Patent: July 19, 2022
    Assignee: TDK CORPORATION
    Inventors: Shunji Saruki, Hiraku Hirabayashi, Masanori Sakai
  • Publication number: 20220214409
    Abstract: This sensor unit includes a base having a substantially-rectangular planar shape including a first side and a second side that are substantially orthogonal to each other, and a plurality of first sensors provided on the base and arranged on a first axis. The first axis is substantially parallel to the first side and passes through a center position of the base.
    Type: Application
    Filed: March 24, 2022
    Publication date: July 7, 2022
    Applicant: TDK CORPORATION
    Inventors: Kunihiro UEDA, Yoshimitsu WADA, Hiraku HIRABAYASHI, Kazuma YAMAWAKI, Tsuyoshi UMEHARA