Patents by Inventor Koo Honjo

Koo Honjo 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: 5606300
    Abstract: A superconducting magnet coil, an insulating layer, and a superconducting magnet which do not generate quenching under cooled and operational conditions are provided by using a fixing resin capable of suppressing microcrack generation in a resin layer which causes quenching.A superconducting magnet coil manufactured by winding a superconducting wire and fixing the wire with resin and a method for manufacturing thereof, wherein said resin is a low cooling restricted thermal stress and high toughness fixing resin having a release rate of elastic energy G.sub.IC at 4.2 K. of at least 250 J.multidot.m.sup.-2, and/or a stress intensity factor K.sub.IC of at least 1.5 MPa.multidot..sqroot.m, and/or a stress safety factor at 4.2 K. of at least 3, and an allowable defect size at least of 0.3 mm.The superconducting magnet coil manufactured in accordance with the present invention does not cause quenching because microcracks are not generated in said resin when the coil is cooled to the liquid helium temperature, i.e.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: February 25, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Toru Koyama, Masao Suzuki, Yasuhiro Mizuno, Koo Honjo, Morimichi Umino, Shigeo Amagi, Shunichi Numata
  • Patent number: 5538942
    Abstract: A superconducting magnet coil is produced by winding a superconducting wire to form a coil; impregnating the coil with a curable resin composition of low viscosity which contains for example at least one epoxy resin selected from the group consisting of diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F and diglycidyl ether of bisphenol AF, all having a number-average molecular weight of 350-1,000, a flexibilizer and a curing catalyst, to obtain a curable-resin composition-impregnated coil; and heating the curable-resin-composition-impregnated coil to cure the composition.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: July 23, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Toru Koyama, Koo Honjo, Masao Suzuki, Akio Takahashi, Akio Mukoh, Keiji Fukushi, Seiji Numata
  • Patent number: 5384197
    Abstract: A superconducting magnet coil contains a coil of superconducting wire and a cured product of a curable resin composition with which the coil has been impregnated, the cured product having a thermal shrinkage factor of 1.5-0.3%, preferably 1.0-0.3%, when cooled from the glass transition temperature to 4.2K, a bend-breaking strain of 2.9-3.9%, preferably 3.2-3.9%, at 4.2K and a modulus of 500-1,000 kg/mm.sup.2 at 4.2K, or undergoing a thermal stress of 0-10 kg/mm.sup.2 when cooled from the glass transition temperature to 4.2K and resisting to quench during superconducting operation.
    Type: Grant
    Filed: December 22, 1993
    Date of Patent: January 24, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Toru Koyama, Koo Honjo, Masao Suzuki, Akio Takahashi, Akio Mukoh, Keiji Fukushi, Seiji Numata