Patents by Inventor Mutsumi Hirai

Mutsumi Hirai 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).

  • Nuclear fuel pellets and method of manufacturing the same
    Patent number: 5429775
    Abstract: The present invention provides improved nuclear fuel pellets having high thermal conductivity for use in an LWR. This can be achieved by creating a continuous deposition phase of high-thermal conductivity substances in the grain boundaries in the pellets. As a result, the temperature in the center of the fuel rod can be significantly reduced, and the discharge amount of gases generated on the nuclear fission can be efficiently reduced.The present invention also provides a method of manufacturing the above-described nuclear fuel pellets.
    Type: Grant
    Filed: August 20, 1992
    Date of Patent: July 4, 1995
    Assignee: Nippon Nuclear Fuel Development Co., Ltd.
    Inventors: Mutsumi Hirai, Shinji Ishimoto, Kenichi Ito
  • Nuclear fuel pellets and method of manufacturing the same
    Patent number: 5362426
    Abstract: The present invention provides improved nuclear fuel pellets having high thermal conductivity for use in an LWR. This can be achieved by creating a continuous deposition phase of high-thermal conductivity substances in the grain boundaries in the pellets. As a result, the temperature in the center of the fuel rod can be significantly reduced, and the discharge amount of gases generated on the nuclear fission can be efficiently reduced.The present invention also provides a method of manufacturing the above-described nuclear fuel pellets.
    Type: Grant
    Filed: June 2, 1993
    Date of Patent: November 8, 1994
    Assignee: Nippon Nuclear Fuel Development Co., Ltd.
    Inventors: Mutsumi Hirai, Shinji Ishimoto, Kenichi Ito
  • Method of manufacturing nuclear fuel pellets
    Patent number: 5255299
    Abstract: The present invention provides improved nuclear fuel pellets having high thermal conductivity for use in an LWR. This can be achieved by creating a continuous deposition phase of high-thermal conductivity substances in the grain boundaries in the pellets. As a result, the temperature in the center of the fuel rod can be significantly reduced, and the discharge amount of gases generated on the nuclear fission can be efficiently reduced.The present invention also provides a method of manufacturing the above-described nuclear fuel pellets.
    Type: Grant
    Filed: June 9, 1992
    Date of Patent: October 19, 1993
    Assignee: Nippon Nuclear Fuel Development Co., Ltd.
    Inventors: Mutsumi Hirai, Shinji Ishimoto, Kenichi Ito
  • Nuclear fuel pellets
    Patent number: 5180527
    Abstract: The present invention provides improved nuclear fuel pellets having high thermal conductivity for use in an LWR. This can be achieved by creating a continuous deposition phase of high-thermal conductivity substances in the grain boundaries in the pellets. As a result, the temperature in the center of the fuel rod can be significantly reduced, and the discharge amount of gases generated on the nuclear fission can be efficiently reduced.The present invention also provides a method of manufacturing the above-described nuclear fuel pellets.
    Type: Grant
    Filed: March 25, 1991
    Date of Patent: January 19, 1993
    Assignee: Nippon Nuclear Fuel Development Co., Ltd.
    Inventors: Mutsumi Hirai, Shinji Ishimoto, Kenichi Ito