Patents by Inventor Kiwamu Shirakawa

Kiwamu Shirakawa 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: 8963544
    Abstract: A magnetic detection element includes a magnetoresistance effect portion composed of a magnetoresistance effect material and a pair of yoke portions. The pair of yoke portions is composed of a soft magnetic material and are respectively arranged so as to be electrically connected to both sides of the magnetoresistance effect portion. The pair of yoke portions guides magnetic flux into the magnetoresistance effect portion. The magnetic detection element also includes a bypass portion, which is composed of a soft magnetic material and is saturated with magnetic flux at lower magnetic field intensity than the yoke portions, and which guides a part of the magnetic flux generated in the yoke portions so as to divert the magnetic flux from the magnetoresistance effect portion.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: February 24, 2015
    Assignee: The Research Institute for Electric and Magnetic Materials
    Inventors: Hirofumi Imatani, Masaaki Yamamoto, Mamiko Naka, Yasushi Kaneta, Kiwamu Shirakawa
  • Publication number: 20110273174
    Abstract: A magnetic detection element includes a magnetoresistance effect portion composed of a magnetoresistance effect material and a pair of yoke portions. The pair of yoke portions is composed of a soft magnetic material and are respectively arranged so as to be electrically connected to both sides of the magnetoresistance effect portion. The pair of yoke portions guides magnetic flux into the magnetoresistance effect portion. The magnetic detection element also includes a bypass portion, which is composed of a soft magnetic material and is saturated with magnetic flux at lower magnetic field intensity than the yoke portions, and which guides a part of the magnetic flux generated in the yoke portions so as to divert the magnetic flux from the magnetoresistance effect portion.
    Type: Application
    Filed: September 29, 2009
    Publication date: November 10, 2011
    Applicant: OMRON CORPORATION
    Inventors: Hirofumi Imatani, Masaaki Yamamoto, Mamiko Naka, Yasushi Kaneta, Kiwamu Shirakawa
  • Patent number: 7218103
    Abstract: A method of manufacturing a thin film magnetic sensor comprising: forming a projection on a surface of an insulating substrate formed of an insulating nonmagnetic material by removing an unnecessary portion of the insulating substrate from a surface region thereof or by depositing a thin film formed of an insulating nonmagnetic material on the surface of the insulating substrate; forming a pair of thin film yokes positioned to face each other with the projection interposed therebetween and completely electrically separated from each other, the thin film yokes being formed by depositing a thin film formed of a soft magnetic material on the surface of the insulating substrate having the projection formed thereon, followed by partially removing the thin film formed of the soft magnetic material until at least a tip surface of the projection is exposed to the outside; and depositing a GMR film having an electrical resistivity higher than that of the soft magnetic material on the tip surface of the projection and
    Type: Grant
    Filed: June 19, 2006
    Date of Patent: May 15, 2007
    Assignees: The Foundation: The Research Institute for Electric and Magnetic Materials, Daido Steel Co., Ltd.
    Inventors: Nobukiyo Kobayashi, Kiwamu Shirakawa, Yasushi Kaneta
  • Patent number: 7170287
    Abstract: A thin film magnetic sensor comprises a pair of thin film yokes each formed of a soft magnetic material, the thin film yokes being arranged to face each other with a gap interposed therebetween; a GMR film electrically connected to the pair of the thin film yokes and having an electrical resistivity higher than that of the soft magnetic material; and an insulating substrate supporting the thin film yokes and the GMR film and formed of an insulating nonmagnetic material. A gap column of a multilayer structure including a layer formed of an insulating nonmagnetic material and a layer of the GMR film is arranged within the gap, and the thickness of the GMR film is uniform over the gap length.
    Type: Grant
    Filed: May 24, 2004
    Date of Patent: January 30, 2007
    Assignees: The Foundation : The Research Institute for Electric and Magnetic Materials, Daido Steel Co., Ltd.
    Inventors: Nobukiyo Kobayashi, Kiwamu Shirakawa, Yasushi Kaneta
  • Publication number: 20060226835
    Abstract: A method of manufacturing a thin film magnetic sensor comprising: forming a projection on a surface of an insulating substrate formed of an insulating nonmagnetic material by removing an unnecessary portion of the insulating substrate from a surface region thereof or by depositing a thin film formed of an insulating nonmagnetic material on the surface of the insulating substrate; forming a pair of thin film yokes positioned to face each other with the projection interposed therebetween and completely electrically separated from each other, the thin film yokes being formed by depositing a thin film formed of a soft magnetic material on the surface of the insulating substrate having the projection formed thereon, followed by partially removing the thin film formed of the soft magnetic material until at least a tip surface of the projection is exposed to the outside; and depositing a GMR film having an electrical resistivity higher than that of the soft magnetic material on the tip surface of the projection and
    Type: Application
    Filed: June 19, 2006
    Publication date: October 12, 2006
    Applicants: THE FOUNDATION: THE RESEARCH INSTITUTE FOR ELECTRIC AND MAGNETIC MATERIALS, DAIDO STEEL CO., LTD.
    Inventors: Nobukiyo Kobayashi, Kiwamu Shirakawa, Yasushi Kaneta
  • Patent number: 6962001
    Abstract: The magnetic north detecting device comprises: a 3-dimensional geomagnetism sensor unit including three geomagnetism sensors for detecting respective components of a geomagnetism magnetic field intensity in respective directions of three coordinate axes perpendicular to each other; and a 3-dimensional operation functional section for carrying out an operation on the basis of the components of the geomagnetism magnetic field intensity detected by the geomagnetism sensors, and calculating a magnetic north direction of the geomagnetism, and the 3-dimensional operation functional section carries out the operation and calculates the magnetic north direction of the geomagnetism, based on two assumptions that: (i) at least one axis of three coordinate axes of the 3-dimensional geomagnetism sensor unit is level to the earth surface; and (ii) an angle of a geomagnetism magnetic field vector which is calculated from the detected components of the geomagnetism magnetic field intensity, referring to the earth surface, co
    Type: Grant
    Filed: November 4, 2004
    Date of Patent: November 8, 2005
    Assignee: The Research Institute for Electric and Magnetic Materials
    Inventors: Takeshi Yano, Kiwamu Shirakawa, Nobukiyo Kobayashi
  • Publication number: 20050115090
    Abstract: The magnetic north detecting device comprises: a 3-dimensional geomagnetism sensor unit including three geomagnetism sensors for detecting respective components of a geomagnetism magnetic field intensity in respective directions of three coordinate axes perpendicular to each other; and a 3-dimensional operation functional section for carrying out an operation on the basis of the components of the geomagnetism magnetic field intensity detected by the geomagnetism sensors, and calculating a magnetic north direction of the geomagnetism, and the 3-dimensional operation functional section carries out the operation and calculates the magnetic north direction of the geomagnetism, based on two assumptions that: (i) at least one axis of three coordinate axes of the 3-dimensional geomagnetism sensor unit is level to the earth surface; and (ii) an angle of a geomagnetism magnetic field vector which is calculated from the detected components of the geomagnetism magnetic field intensity, referring to the earth surface, co
    Type: Application
    Filed: November 4, 2004
    Publication date: June 2, 2005
    Applicant: THE FOUNDATION: THE RESEARCH INSTITUTE FOR ELECTRIC AND MAGNETIC MATERIALS
    Inventors: Takeshi Yano, Kiwamu Shirakawa, Nobukiyo Kobayashi
  • Publication number: 20040239321
    Abstract: A thin film magnetic sensor comprises a pair of thin film yokes each formed of a soft magnetic material, the thin film yokes being arranged to face each other with a gap interposed therebetween; a GMR film electrically connected to the pair of the thin film yokes and having an electrical resistivity higher than that of the soft magnetic material; and an insulating substrate supporting the thin film yokes and the GMR film and formed of an insulating nonmagnetic material. A gap column of a multilayer structure including a layer formed of an insulating nonmagnetic material and a layer of the GMR film is arranged within the gap, and the thickness of the GMR film is uniform over the gap length.
    Type: Application
    Filed: May 24, 2004
    Publication date: December 2, 2004
    Applicants: THE FOUNDATION: THE RESEARCH INSTITUTE FOR ELECTRIC AND MAGNETIC MATERIALS, DAIDO STEEL CO., LTD.
    Inventors: Nobukiyo Kobayashi, Kiwamu Shirakawa, Yasushi Kaneta
  • Publication number: 20040239320
    Abstract: A thin film magnetic sensor comprises a pair of first thin film yoke and second thin film yoke each formed of a soft magnetic material, the first and second thin film yokes being positioned to face each other with a gap interposed therebetween; a GMR film having an electrical resistivity higher than that of the soft magnetic material and formed in the gap so as to be electrically connected to the first thin film yoke and the second thin film yoke; and an insulating substrate made of an insulating nonmagnetic material and serving to support the first thin film yoke, the second thin film yoke and the GMR film. The GMR film is formed on a facing surface of the first thin film yoke positioned to face the second thin film yoke, and the length of the gap is defined by the thickness of the GMR film positioned on the facing surface of the first thin film yoke.
    Type: Application
    Filed: May 24, 2004
    Publication date: December 2, 2004
    Applicants: THE FOUNDATION: THE RESEARCH INSTITUTE FOR ELECTRIC AND MAGNETIC MATERIALS, DAIDO STEEL CO., LTD
    Inventors: Nobukiyo Kobayashi, Kiwamu Shirakawa, Yasushi Kaneta
  • Patent number: 6642714
    Abstract: A thin-film magnetic field sensor is provided which includes two arms of a bridge circuit formed of a first element having a giant-magneto-resistant thin-film, and soft magnetic thin-films disposed one on either side thereof, with electrical terminals, and a second element having a giant-magneto-resistant thin-film, and conductive films disposed one on either side thereof, with electrical terminals. The electrical resistance value of the second element has sensitivity relative to the magnetic field, such that it is substantially zero when the magnetic field is small, but it changes equally to the first element due to causes other than the magnetic field. Since the output of the bridge circuit is in proportion to the difference in electrical resistance values between the first and second elements, part of a change due to causes other than the magnetic field is canceled in the output of the bridge circuit, whereby the magnetic field value can be accurately measured.
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: November 4, 2003
    Assignee: The Research Institute for Electric and Magnetic Materials
    Inventors: Nobukiyo Kobayashi, Takeshi Yano, Shigehiro Ohnuma, Kiwamu Shirakawa, Tsuyoshi Masumoto
  • Publication number: 20030042902
    Abstract: There is provided a thin-film magnetic field sensor, which has a simple structure and a high detecting sensitivity, and reduces measurement errors due to temperature variation or the like. In the thin-film magnetic field sensor according to the present invention, two arms of a bridge circuit are formed of an element 5 having a giant-magneto-resistant thin-film, and soft magnetic thin-films disposed one on either side thereof, with electrical terminals, and an element 10 having a giant-magneto-resistant thin-film, and conductive films disposed one on either side thereof, with electrical terminals. The electrical resistance value of the element 10 has sensitivity relative to the magnetic field, such that it is substantially zero when the magnetic field is small, but it changes equally to the element 5 due to causes other than the magnetic field.
    Type: Application
    Filed: August 22, 2002
    Publication date: March 6, 2003
    Applicant: THE RESEARCH INSTITUTE FOR ELECTRIC AND MAGNETIC MATERIALS
    Inventors: Nobukiyo Kobayashi, Takeshi Yano, Shigehiro Ohnuma, Kiwamu Shirakawa, Tsuyoshi Masumoto