Patents by Inventor Yota Ichiki

Yota Ichiki 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: 10804624
    Abstract: The present invention provides a joint portion of MgB2 superconducting wires having exceptional energization characteristics and high reliability. The joint portion of the superconducting wires according to the present invention has a space for filling Mg into a portion inside a container or pressurizing member, the portion not being adjacent to an MgB2 sintered body.
    Type: Grant
    Filed: May 12, 2017
    Date of Patent: October 13, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Yota Ichiki, Kazutaka Okamoto
  • Patent number: 10714238
    Abstract: The problem is to attain a joint for multi-core superconducting wires having a high critical current property. The joint for superconducting wires of the present invention has a first sintered body containing MgB2 configured to fix a plurality of superconducting wires, and a second sintered body containing MgB2 configured to joint the superconducting wires.
    Type: Grant
    Filed: February 3, 2016
    Date of Patent: July 14, 2020
    Assignee: HITACHI, LTD.
    Inventors: Yota Ichiki, Tsuyoshi Wakuda
  • Publication number: 20190295746
    Abstract: It is an object of the present invention to provide an MgB2 wire helping to achieve compatibility between the ease with which superconducting connection is effected and thermal stability. A superconducting wire according to the present invention includes: an elemental wire formed of MgB2; and a first metal not reacting with Mg. In a section orthogonal to the longitudinal direction of the superconducting wire, the region extending from the center of the superconducting wire to the installation position of the elemental wire is formed by the elemental wire and the first metal.
    Type: Application
    Filed: July 24, 2015
    Publication date: September 26, 2019
    Inventors: Hideki TANAKA, Kazuya NISHI, Takaaki SUZUKI, Yota ICHIKI
  • Publication number: 20190207331
    Abstract: The present invention provides a joint portion of MgB2 superconducting wires having exceptional energization characteristics and high reliability. The joint portion of the superconducting wires according to the present invention has a space for filling Mg into a portion inside a container or pressurizing member, the portion not being adjacent to an MgB2 sintered body.
    Type: Application
    Filed: May 12, 2017
    Publication date: July 4, 2019
    Inventors: Yota ICHIKI, Kazutaka OKAMOTO
  • Patent number: 9887029
    Abstract: A technical problem is to turn a persistent current switch on and off at high speed with less heat input. The invention relates to a conductive cooling-type persistent current switch, including: a superconductive wire 1 through which a current is passed; a cooling stage 9 which cools the superconductive wire; and a heater 8 which heats the superconductive wire, wherein the superconductive wire is placed between faces which are each formed by the cooling stage and the heater, a core of the superconductive wire is magnesium diboride 6, and a base material 5 placed around an outer periphery of the core is a material having a resistivity of 10 ??cm or more at 40 K.
    Type: Grant
    Filed: July 12, 2013
    Date of Patent: February 6, 2018
    Assignee: HITACHI, LTD.
    Inventors: Motomune Kodama, Kazuhide Tanaka, Yota Ichiki
  • Publication number: 20180012682
    Abstract: The problem is to attain a joint for multi-core superconducting wires having a high critical current property. The joint for superconducting wires of the present invention has a first sintered body containing MgB2 configured to fix a plurality of superconducting wires, and a second sintered body containing MgB2 configured to joint the superconducting wires.
    Type: Application
    Filed: February 3, 2016
    Publication date: January 11, 2018
    Applicant: Hitachi Ltd.
    Inventors: Yota ICHIKI, Tsuyoshi WAKUDA
  • Publication number: 20150228391
    Abstract: A technical problem is to turn a persistent current switch on and off at high speed with less heat input. The invention relates to a conductive cooling-type persistent current switch, including: a superconductive wire 1 through which a current is passed; a cooling stage 9 which cools the superconductive wire; and a heater 8 which heats the superconductive wire, wherein the superconductive wire is placed between faces which are each formed by the cooling stage and the heater, a core of the superconductive wire is magnesium diboride 6, and a base material 5 placed around an outer periphery of the core is a material having a resistivity of 10 ??cm or more at 40 K.
    Type: Application
    Filed: July 12, 2013
    Publication date: August 13, 2015
    Applicant: Hitachi, Ltd.,
    Inventors: Motomune Kodama, Kazuhide Tanaka, Yota Ichiki
  • Patent number: 8644897
    Abstract: Provided is a superconducting apparatus, including a joint of superconducting wires having high electric conduction characteristics and a superconducting magnet or the like. The superconducting joint comprises a plurality of superconducting wires and a sinter which integrates the plurality of superconducting wires. Herein, at least any one of the superconducting wires is a MgB2 superconducting wire, the sinter contains MgB2, and the sinter is compressed form the direction different from the direction toward which the superconducting wires protrude. Further, in order to form such a joint, a compression vessel provided with an opening used for introducing raw material powders to construct the sinter and another opening used for inserting the superconducting wires is utilized, and the openings are directed to different directions each other. Accordingly, MgB2 is filled in the sinter at high density, allowing the joint structure to have a good bonding property among particles.
    Type: Grant
    Filed: October 27, 2011
    Date of Patent: February 4, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Yota Ichiki, Tsuyoshi Wakuda, Kazuhide Tanaka
  • Patent number: 8400747
    Abstract: In a superconducting coil, a parallel conductor includes a plurality of superconducting wires bundled and wound in a coil. The superconducting wires have at least two connections therebetween. A current source connected to the superconducting wires to form a loop via the superconducting wires and the connection to supply a current in the loop when a quench is detected. A superconducting magnet includes the superconducting coil, a persistent current switch connected to the superconducting coil, and a quench detector configured to detect quench occurring in the superconducting coil.
    Type: Grant
    Filed: July 13, 2011
    Date of Patent: March 19, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Yota Ichiki, Tsuyoshi Wakuda, Minseok Park
  • Publication number: 20120108435
    Abstract: Provided is a superconducting apparatus, including a joint of superconducting wires having high electric conduction characteristics and a superconducting magnet or the like. The superconducting joint comprises a plurality of superconducting wires and a sinter which integrates the plurality of superconducting wires. Herein, at least any one of the superconducting wires is a MgB2 superconducting wire, the sinter contains MgB2, and the sinter is compressed form the direction different from the direction toward which the superconducting wires protrude. Further, in order to form such a joint, a compression vessel provided with an opening used for introducing raw material powders to construct the sinter and another opening used for inserting the superconducting wires is utilized, and the openings are directed to different directions each other. Accordingly, MgB2 is filled in the sinter at high density, allowing the joint structure to have a good bonding property among particles.
    Type: Application
    Filed: October 27, 2011
    Publication date: May 3, 2012
    Inventors: Yota ICHIKI, Tsuyoshi Wakuda, Kazuhide Tanaka
  • Publication number: 20120094840
    Abstract: Magnetic field attenuation in a persistent current mode operation is prevented, heat generation at a connecting part between the persistent current switch and the superconducting coil, and increase in a cooling temperature of the superconducting coil in a current supplying mode is suppressed to a minimum.
    Type: Application
    Filed: February 26, 2010
    Publication date: April 19, 2012
    Inventors: Hiroyuki Tanaka, Michiya Okada, Masaya Takahashi, Yota Ichiki
  • Publication number: 20120014030
    Abstract: In a superconducting coil, a parallel conductor includes a plurality of superconducting wires bundled and wound in a coil. The superconducting wires have at least two connections therebetween. A current source connected to the superconducting wires to form a loop via the superconducting wires and the connection to supply a current in the loop when a quench is detected. A superconducting magnet includes the superconducting coil, a persistent current switch connected to the superconducting coil, and a quench detector configured to detect quench occurring in the superconducting coil.
    Type: Application
    Filed: July 13, 2011
    Publication date: January 19, 2012
    Inventors: Yota ICHIKI, Tsuyoshi WAKUDA, Minseok PARK
  • Publication number: 20120004110
    Abstract: It is an objective of the present invention to provide a method for manufacturing long lengths of MgB2 superconducting wire having excellent superconducting properties and an MgB2 superconducting wire manufactured thereby. There is provided a method for manufacturing a magnesium diboride superconducting wire, comprising the successive steps of: filling a metallic tube with a raw material powder; and subjecting the tube to wiredrawing processing, in which a fatty acid metal salt or a mixture of the fatty acid metal salt and a fatty acid is added to the raw material powder.
    Type: Application
    Filed: June 29, 2011
    Publication date: January 5, 2012
    Inventors: Masaya TAKAHASHI, Tsuyoshi Wakuda, Yota Ichiki, Kazuhide Tanaka
  • Publication number: 20110218111
    Abstract: A parallel conductor comprising a bundle of a plurality of high temperature superconducting wire materials, ends of the wire materials being electrically connected to each other, wherein each of the high temperature wire materials has at least one short-circuited portion where the wire materials are connected by means of a non-superconducting conductive material, and portions other than the short-circuited portion being covered with an insulating material.
    Type: Application
    Filed: February 24, 2011
    Publication date: September 8, 2011
    Inventors: Yota ICHIKI, Tsuyoshi Wakuda, Minseok Park, Masaya Takahashi