Patents by Inventor Yoshinori Ohki

Yoshinori Ohki 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: 11980106
    Abstract: A persistent current switch includes a superconducting wire including a substrate and a superconducting layer disposed on the substrate, and a heater. The superconducting wire includes a surface including a first portion and a second portion that are disposed apart from each other along a longitudinal direction of the superconducting wire. The first portion and the second portion face each other. The heater is sandwiched between the first portion and the second portion.
    Type: Grant
    Filed: August 31, 2020
    Date of Patent: May 7, 2024
    Assignees: Sumitomo Electric Industries, Ltd., RIKEN, Japan Superconductor Technology, Inc.
    Inventors: Takashi Yamaguchi, Kotaro Ohki, Tatsuoki Nagaishi, Yoshinori Yanagisawa, Mamoru Hamada
  • Patent number: 11972898
    Abstract: A superconducting magnet according to one embodiment includes: a coil including a superconducting layer having a first portion and a second portion, and a joining portion; and a cryostat in which the coil is stored. The first portion and the second portion are located in a termination portion. The superconducting layer forms a closed loop by superconducting joining of the first portion and the second portion at the joining portion. The superconducting layer is made of a high-temperature superconductor. A current flows through the joining portion in a superconducting state when a magnetic field equal to or greater than 1.0 tesla and equal to or less than 5.0 tesla is applied to the joining portion at 77 kelvin. The cryostat is configured such that a temperature inside the cryostat is equal to or greater than 2.0 kelvin and equal to or less than 77 kelvin.
    Type: Grant
    Filed: March 9, 2018
    Date of Patent: April 30, 2024
    Assignees: RIKEN, Sumitomo Electric Industries, Ltd.
    Inventors: Hideaki Maeda, Yoshinori Yanagisawa, Kotaro Ohki, Tatsuoki Nagaishi
  • Patent number: 5115777
    Abstract: A method and an apparatus for driving an auxiliary device of an internal combustion engine according to the present invention is directed to preventing an over revolution of an engine by detecting a speed of the revolution of the engine, regardless the magnitude of an induced voltage of a primary winding of an ignition device.
    Type: Grant
    Filed: February 22, 1990
    Date of Patent: May 26, 1992
    Assignee: Iida Denki Kogyo Co., Ltd.
    Inventors: Yoshinori Ohki, Hiroshi Mochizuki
  • Patent number: 4207852
    Abstract: The present invention discloses a system which utilizes the storage action of capacitors and the characteristic of the turn-off operation due to a potential difference between the base and emitter of a transistor, and immediately after a primary short-circuit current flowing through a primary winding of an ignition coil has reached a maximum, that is, immediately after a forward induced voltage in the primary winding has reached a maximum, the primary short-circuit current is cut off in accordance with information in which the forward induced voltage in the primary winding is at its maximum to always effect the ignition operation immediately after the primary short-circuit current is at its maximum.
    Type: Grant
    Filed: February 7, 1979
    Date of Patent: June 17, 1980
    Assignee: Iida Denki Kogyo Co., Ltd.
    Inventors: Yoshinori Ohki, Hirokichi Komiya
  • Patent number: 4204490
    Abstract: In a non contact ignition circuit for an internal combustion engine, a current induced in the primary winding or an ignition coil is controlled and cut-off by operation, on and off, of a thyristor so as to produce a discharge in a spark plug. A capacitor connected to the gate of the thyristor is charged with an inverse voltage. When the rotational speed of the internal combustion engine exceeds a predetermined level, i.e. a state of overrotation, the inverse voltage stored in the capacitor is discharged whereby the gate potential of the thyristor is negatively biased relative to the cathode. Accordingly, during the discharging period of the capacitor, the triggering time of the thyristor and sparking are retarded as compared to the normal running condition of the internal combustion engine. Thereby overrotation of the internal combustion engine is prevented.
    Type: Grant
    Filed: May 17, 1978
    Date of Patent: May 27, 1980
    Assignee: Iida Denki Kogyo K.K.
    Inventors: Yoshinori Ohki, Komiya Hirokichi
  • Patent number: 4144859
    Abstract: In a non contact ignition circuit for an internal combustion engine, a current induced in the primary winding of an ignition coil is controlled and cut-off by operation, on and off, of a thyristor so as to produce a discharge in a spark plug. A capacitor connected to the gate of the thyristor is charged with an inverse voltage. When the rotational speed of the internal combustion engine exceeds a predetermined level, i.e. a state of overrotation, the inverse voltage stored in the capacitor is discharged whereby the gate potential of the thyristor is negatively biased relative to the cathode. Accordingly, during the discharging period of the capacitor, the triggering time of the thyristor and sparking are retarded as compared to the normal running condition of the internal combustion engine. Thereby overrotation of the internal combustion engine is prevented.
    Type: Grant
    Filed: December 8, 1976
    Date of Patent: March 20, 1979
    Assignee: Iida Denki Kogyo K.K.
    Inventors: Yoshinori Ohki, Komiya Hirokichi
  • Patent number: 4090488
    Abstract: This invention relates to a method for preventing premature ignition in an ignition device for the internal combustion engine including a non-contact type ignition circuit for the internal combustion engine, particularly an ignition circuit for the internal combustion engine in which an inductive current in the form of an AC waveform induced in a primary winding of an ignition coil is controlled in its conduction and cut-off by means of a transistor circuit, various auxiliary circuits to be disposed for a desired performance in accordance with the purpose of use and the rate of this circuit, and an ignition circuit for the internal combustion engine in accordance with the present invention, and more particularly to a method for preventing premature ignition in an ignition device for the internal combustion engine comprising a transistor circuit for controlling in conduction and cut-off of a primary short-circuit current in the whole circuit and a trigger circuit for controlling the trigger in said transistor
    Type: Grant
    Filed: December 15, 1975
    Date of Patent: May 23, 1978
    Assignee: Iida Denki Kogyo K.K.
    Inventors: Yoshinori Ohki, Yoshio Kato
  • Patent number: 3958546
    Abstract: This invention relates to a method for preventing premature ignition in an ignition device for the internal combustion engine including a non-contact type ignition circuit for the internal combustion engine, particularly an ignition circuit for the internal combustion engine in which an inductive current in the form of an AC waveform induced in a primary winding of an ignition coil is controlled in its conduction and cut-off by means of a transistor circuit, various auxiliary circuits to be disposed for a desired performance in accordance with the purpose of use and the rate of this circuit, and an ignition circuit for the internal combustion engine in accordance with the present invention, and more particularly to a method for preventing premature ignition in an ignition device for the internal combustion engine comprising a transistor circuit for controlling in conduction and cut-off of a primary short-circuit current in the whole circuit and a trigger circuit for controlling the trigger in said transistor
    Type: Grant
    Filed: December 27, 1973
    Date of Patent: May 25, 1976
    Assignee: Iida Denki Kogyo K.K.
    Inventors: Yoshinori Ohki, Yoshio Kato