Patents by Inventor Tohru Ishikawa

Tohru Ishikawa 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: 11960618
    Abstract: A computer implemented method searches data. A number of processor units generates a candidate search result using an index for a data source in response to a search query by a user, wherein the candidate search result comprises files accessible by the user based on access control information in the index. The number of processor units generates a completed search result with a set of the files from the candidate search result having a confidentiality level less than or equal to a threshold confidentiality level. The number of processor units determines whether the user has access to a file in the candidate search result in which the file has the confidentiality level greater than the threshold confidentiality level for the data source. The number of processor units adds the file to the completed search result in response to the file being accessible by the user in the data source.
    Type: Grant
    Filed: September 1, 2021
    Date of Patent: April 16, 2024
    Assignee: International Business Machines Corporation
    Inventors: Tohru Hasegawa, Shunsuke Ishikawa, Yasumasa Kajinaga, Keisuke Nitta, Daiki Tsuzuku
  • Patent number: 11703021
    Abstract: In a fuel injection device, a driving unit structure has a magnetic aperture, in which an inner diameter is gradually enlarged toward the mover side, provided in an inner peripheral surface of the magnetic core. It is possible to reduce magnetic delay time upon valve opening from the supply of the electric current to the coil to the rise of magnetic flux and magnetic delay time upon valve closing from the stoppage of the electric current to the coil to reduction of magnetic flux, by providing a magnetic aperture in the inner peripheral surface of the magnetic core. Thus it is possible to improve the dynamic responsiveness upon valve opening and valve closing.
    Type: Grant
    Filed: June 21, 2021
    Date of Patent: July 18, 2023
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Ryo Kusakabe, Motoyuki Abe, Tohru Ishikawa, Noriyuki Maekawa, Masahiro Soma, Takao Miyake, Yasuo Namaizawa
  • Publication number: 20210310452
    Abstract: In a fuel injection device, a driving unit structure has a magnetic aperture, in which an inner diameter is gradually enlarged toward the mover side, provided in an inner peripheral surface of the magnetic core. It is possible to reduce magnetic delay time upon valve opening from the supply of the electric current to the coil to the rise of magnetic flux and magnetic delay time upon valve closing from the stoppage of the electric current to the coil to reduction of magnetic flux, by providing a magnetic aperture in the inner peripheral surface of the magnetic core. Thus it is possible to improve the dynamic responsiveness upon valve opening and valve closing.
    Type: Application
    Filed: June 21, 2021
    Publication date: October 7, 2021
    Inventors: Ryo KUSAKABE, Motoyuki ABE, Tohru ISHIKAWA, Noriyuki MAEKAWA, Masahiro SOMA, Takao MIYAKE, Yasuo NAMAIZAWA
  • Patent number: 11067045
    Abstract: In a fuel injection device, a driving unit structure has a magnetic aperture, in which an inner diameter is gradually enlarged toward the mover side, provided in an inner peripheral surface of the magnetic core. It is possible to reduce magnetic delay time upon valve opening from the supply of the electric current to the coil to the rise of magnetic flux and magnetic delay time upon valve closing from the stoppage of the electric current to the coil to reduction of magnetic flux, by providing a magnetic aperture in the inner peripheral surface of the magnetic core. Thus it is possible to improve the dynamic responsiveness upon valve opening and valve closing.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: July 20, 2021
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Ryo Kusakabe, Motoyuki Abe, Tohru Ishikawa, Noriyuki Maekawa, Masahiro Soma, Takao Miyake, Yasuo Namaizawa
  • Patent number: 10995655
    Abstract: A fuel injection device including a valve body having an injection hole-formed part having a plurality of injection holes on the leading end side of the valve body. An injection hole comprises a crossing angle, ?1, between a central axis of the injection hole-formed part and an injection hole axis, and another injection hole comprises a crossing angle, ?2, between the central axis and another injection hole axis. ?2 is larger than ?1. The injection holes are formed such that a distance between the central axis and an inlet surface center of the injection hole is longer than a distance between the central axis and another inlet surface center of the another injection hole. A straight line beyond an outlet surface in the injection hole axis does not intersect with another straight line beyond another outlet surface in the another injection hole axis.
    Type: Grant
    Filed: November 21, 2017
    Date of Patent: May 4, 2021
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Akira Iizuka, Tohru Ishikawa, Takao Miyake, Kazuki Yoshimura
  • Patent number: 10900435
    Abstract: In a drive unit of a fuel injection device, an electric current is supplied to the fuel injection device by applying a high voltage to the fuel injection device from a high voltage source whose voltage is boosted to a voltage higher than a battery voltage at the time of opening a valve of the fuel injection device. Thereafter, the electric current supplied to the fuel injection device is lowered to a current value at which a valve element cannot be held in a valve open state by stopping the applying of the high voltage from the high voltage source. Thereafter, in a stage where a supply current is switched to a hold current, another high voltage is applied to the fuel injection device from the high voltage source.
    Type: Grant
    Filed: March 27, 2019
    Date of Patent: January 26, 2021
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Ryo Kusakabe, Motoyuki Abe, Hideharu Ehara, Tohru Ishikawa, Takuya Mayuzumi, Kenji Hiraku
  • Patent number: 10859047
    Abstract: A drive unit of a fuel injection device includes a driver circuit. The driver circuit opens and closes a valve element of the fuel injection device by supplying a drive current to the fuel injection device. The driver circuit supplies the drive current to open the valve element and sets the drive current to zero in an intermediate lift area. The intermediate lift area is an area is which a lift amount of the valve element is smaller than a maximum target lift amount.
    Type: Grant
    Filed: August 23, 2018
    Date of Patent: December 8, 2020
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Ryo Kusakabe, Motoyuki Abe, Yoshihito Yasukawa, Noriyuki Maekawa, Takuya Mayuzumi, Tohru Ishikawa
  • Patent number: 10704518
    Abstract: A spark-ignition direct fuel injection valve includes, at least, a seat member provided with a fuel injection hole and a valve seat and a valve body which controls fuel injection from the injection hole by contacting and separating from the valve seat. In the spark-ignition direct fuel injection valve: the injection hole has an injection hole inlet which is open inwardly of the seat member and an injection hole outlet which is open outwardly of the seat member; an opening edge of the injection hole inlet has a first round-chamfered portion formed on an upstream side with respect to a fuel flow toward the injection hole inlet; and an extending length (L) of the injection hole does not exceed three times a hole diameter (D) of the injection hole.
    Type: Grant
    Filed: June 19, 2018
    Date of Patent: July 7, 2020
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yoshihito Yasukawa, Kiyotaka Ogura, Takao Miyake, Eiji Ishii, Motoyuki Abe, Tohru Ishikawa
  • Publication number: 20190257264
    Abstract: A fuel injection device including a valve body having an injection hole-formed part having a plurality of injection holes on the leading end side of the valve body. An injection hole comprises a crossing angle, ?1, between a central axis of the injection hole-formed part and an injection hole axis, and another injection hole comprises a crossing angle, ?2, between the central axis and another injection hole axis. ?2 is larger than ?1. The injection holes are formed such that a distance between the central axis and an inlet surface center of the injection hole is longer than a distance between the central axis and another inlet surface center of the another injection hole. A straight line beyond an outlet surface in the injection hole axis does not intersect with another straight line beyond another outlet surface in the another injection hole axis.
    Type: Application
    Filed: November 21, 2017
    Publication date: August 22, 2019
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Akira IIZUKA, Tohru ISHIKAWA, Takao MIYAKE, Kazuki YOSHIMURA
  • Publication number: 20190218987
    Abstract: In a drive unit of a fuel injection device, an electric current is supplied to the fuel injection device by applying a high voltage to the fuel injection device from a high voltage source whose voltage is boosted to a voltage higher than a battery voltage at the time of opening a valve of the fuel injection device. Thereafter, the electric current supplied to the fuel injection device is lowered to a current value at which a valve element cannot be held in a valve open state by stopping the applying of the high voltage from the high voltage source. Thereafter, in a stage where a supply current is switched to a hold current, another high voltage is applied to the fuel injection device from the high voltage source.
    Type: Application
    Filed: March 27, 2019
    Publication date: July 18, 2019
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Ryo KUSAKABE, Motoyuki ABE, Hideharu EHARA, Tohru ISHIKAWA, Takuya MAYUZUMI, Kenji HIRAKU
  • Patent number: 10288022
    Abstract: In an electromagnetic fuel injection which is structured such that both end surfaces of an inner circumferential iron core portion and an outer circumferential iron core portion face a movable iron core, and a non-magnetic portion made of a metal material is provided between both end surfaces, an object of the present invention is to realize a structure of the electromagnetic fuel injector in which a surface of a target object is unlikely to be affected by a heat treatment with the surface facing the movable iron core.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: May 14, 2019
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Yoshihito Yasukawa, Hideharu Ehara, Tohru Ishikawa, Kiyotaka Ogura, Motoyuki Abe, Ryo Kusakabe, Akiyasu Miyamoto
  • Patent number: 10280862
    Abstract: In a drive unit of a fuel injection device, an electric current is supplied to the fuel injection device by applying a high voltage to the fuel injection device from a high voltage source whose voltage is boosted to a voltage higher than a battery voltage at the time of opening a valve of the fuel injection device. Thereafter, the electric current supplied to the fuel injection device is lowered to a current value at which a valve element cannot be held in a valve open state by stopping the applying of the high voltage from the high voltage source. Thereafter, in a stage where a supply current is switched to a hold current, another high voltage is applied to the fuel injection device from the high voltage source.
    Type: Grant
    Filed: February 13, 2017
    Date of Patent: May 7, 2019
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Ryo Kusakabe, Motoyuki Abe, Hideharu Ehara, Tohru Ishikawa, Takuya Mayuzumi, Kenji Hiraku
  • Patent number: 10240567
    Abstract: A fuel injection valve includes a valve body, a coil, an inner fixed iron core that is arranged on an inner peripheral side of the coil, and an outer fixed iron core that is arranged on an outer peripheral side of the coil. The fuel injection valve also includes a movable element that is configured to be attracted to the inner fixed iron core and the outer fixed iron core, wherein the movable element is configured to be separable from the valve body and is configured to move the valve body.
    Type: Grant
    Filed: July 3, 2017
    Date of Patent: March 26, 2019
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Yoshihito Yasukawa, Hideharu Ehara, Tohru Ishikawa, Motoyuki Abe, Ryo Kusakabe
  • Publication number: 20190063387
    Abstract: A fuel injection valve includes a valve body, a coil, an inner fixed iron core that is arranged on an inner peripheral side of the coil, and an outer fixed iron core that is arranged on an outer peripheral side of the coil. The fuel injection valve also includes a movable element that is configured to be attracted to the inner fixed iron core and the outer fixed iron core, wherein the movable element is configured to be separable from the valve body and is configured to move the valve body.
    Type: Application
    Filed: October 24, 2018
    Publication date: February 28, 2019
    Inventors: Yoshihito YASUKAWA, Hideharu EHARA, Tohru ISHIKAWA, Motoyuki ABE, Ryo KUSAKABE
  • Publication number: 20180363615
    Abstract: A spark-ignition direct fuel injection valve includes, at least, a seat member provided with a fuel injection hole and a valve seat and a valve body which controls fuel injection from the injection hole by contacting and separating from the valve seat. In the spark-ignition direct fuel injection valve: the injection hole has an injection hole inlet which is open inwardly of the seat member and an injection hole outlet which is open outwardly of the seat member; an opening edge of the injection hole inlet has a first round-chamfered portion formed on an upstream side with respect to a fuel flow toward the injection hole inlet; and an extending length (L) of the injection hole does not exceed three times a hole diameter (D) of the injection hole.
    Type: Application
    Filed: June 19, 2018
    Publication date: December 20, 2018
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Yoshihito YASUKAWA, Kiyotaka OGURA, Takao MIYAKE, Eiji ISHII, Motoyuki ABE, Tohru ISHIKAWA
  • Publication number: 20180363608
    Abstract: A drive unit of a fuel injection device includes a driver circuit. The driver circuit opens and closes a valve element of the fuel injection device by supplying a drive current to the fuel injection device. The driver circuit supplies the drive current to open the valve element and sets the drive current to zero in an intermediate lift area. The intermediate lift area is an area is which a lift amount of the valve element is smaller than a maximum target lift amount.
    Type: Application
    Filed: August 23, 2018
    Publication date: December 20, 2018
    Inventors: Ryo KUSAKABE, Motoyuki ABE, Yoshihito YASUKAWA, Noriyuki MAEKAWA, Takuya MAYUZUMI, Tohru ISHIKAWA
  • Patent number: 10082117
    Abstract: A method of controlling a fuel injection device that can control a small amount of injection is provided. A fuel injection device for use in an internal combustion engine, includes: a valve body that can open and close a fuel passage, a needle that transfers a force with the valve body, and executes valve opening/closing operation, and an electromagnet that includes a coil and a magnetic core provided as a driver for driving the needle, and a cylindrical nozzle holder disposed on an outer periphery of the magnetic core and the needle, in which a current is supplied to the coil to exert a magnetic attractive force between the magnetic core and the needle to open the valve body.
    Type: Grant
    Filed: April 21, 2016
    Date of Patent: September 25, 2018
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Ryo Kusakabe, Motoyuki Abe, Yoshihito Yasukawa, Noriyuki Maekawa, Takuya Mayuzumi, Tohru Ishikawa
  • Patent number: 10024288
    Abstract: A spark-ignition direct fuel injection valve includes, at least, a seat member provided with a fuel injection hole and a valve seat and a valve body which controls fuel injection from the injection hole by contacting and separating from the valve seat. In the spark-ignition direct fuel injection valve: the injection hole has an injection hole inlet which is open inwardly of the seat member and an injection hole outlet which is open outwardly of the seat member; an opening edge of the injection hole inlet has a first round-chamfered portion formed on an upstream side with respect to a fuel flow toward the injection hole inlet; and an extending length (L) of the injection hole does not exceed three times a hole diameter (D) of the injection hole.
    Type: Grant
    Filed: May 10, 2017
    Date of Patent: July 17, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yoshihito Yasukawa, Kiyotaka Ogura, Takao Miyake, Eiji Ishii, Motoyuki Abe, Tohru Ishikawa
  • Publication number: 20170298882
    Abstract: A fuel injection valve includes a valve body, a coil, an inner fixed iron core that is arranged on an inner peripheral side of the coil, and an outer fixed iron core that is arranged on an outer peripheral side of the coil. The fuel injection valve also includes a movable element that is configured to be attracted to the inner fixed iron core and the outer fixed iron core, wherein the movable element is configured to be separable from the valve body and is configured to move the valve body.
    Type: Application
    Filed: July 3, 2017
    Publication date: October 19, 2017
    Inventors: Yoshihito YASUKAWA, Hideharu EHARA, Tohru ISHIKAWA, Motoyuki ABE, Ryo KUSAKABE
  • Publication number: 20170241391
    Abstract: A spark-ignition direct fuel injection valve includes, at least, a seat member provided with a fuel injection hole and a valve seat and a valve body which controls fuel injection from the injection hole by contacting and separating from the valve seat. In the spark-ignition direct fuel injection valve: the injection hole has an injection hole inlet which is open inwardly of the seat member and an injection hole outlet which is open outwardly of the seat member; an opening edge of the injection hole inlet has a first round-chamfered portion formed on an upstream side with respect to a fuel flow toward the injection hole inlet; and an extending length (L) of the injection hole does not exceed three times a hole diameter (D) of the injection hole.
    Type: Application
    Filed: May 10, 2017
    Publication date: August 24, 2017
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Yoshihito YASUKAWA, Kiyotaka OGURA, Takao MIYAKE, Eiji ISHII, Motoyuki ABE, Tohru ISHIKAWA