Patents by Inventor Hiromi Iwai

Hiromi Iwai 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: 5985000
    Abstract: To provide a Cu-Cr alloy electrode material, a mixture of Cu and cr materials at a predetermined ratio is heated until the mixture has been entirely melted, and the molten metal obtained is quenched to precipitate fine Cr particles in a Cu base. Since Cr is melted into Cu before quenching, and then Cr precipitates, Cr particles finer than those in the sintering or infiltration method can disperse in a Cu base. This invention prevents defects such as voids in the structure and the weakening of the fusion of Cu and Cr or failure of Cr to precipitate into the Cu base caused by oxide films on the surface of the Cr particles, thereby providing a fine alloy structure.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: November 16, 1999
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Hisaji Shinohara, Katsuro Shiozaki, Kazuro Shibata, Masayuki Furusawa, Shunichi Hatakeyama, Hiromi Iwai, Tatsuo Take, Tsuneki Shinokura
  • Patent number: 4866393
    Abstract: A method of diagnosing the deterioration of a zinc oxide type lighting arrester having one or more series-connected non-linear resistance elements including steps of elimination of the effects of capacitive currents from phase currents; obtaining a synthesized waveform using a window type transformer based on the resistance elements alone; and diagnosing the presence of a deteriorated non-linear resistance element by generating a first pulse voltage when the maximum crest value of the synthesized waveforms exceeds a predetermined value, generating a second pulse voltage representative of terminal voltage of the resistance element, and calculating the difference between the first and second pulse voltages.
    Type: Grant
    Filed: October 2, 1987
    Date of Patent: September 12, 1989
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Hiromi Iwai, Masatoshi Nakajima, Hiroshi Asaga, Nobuyuki Takao, Satoru Shiga, Yoshihiro Tanabe