Patents by Inventor Naoko Iwashimizu

Naoko Iwashimizu 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: 5403374
    Abstract: A watch exterior part is formed of cemented carbide or stellite alloy, and has a three-dimensionally curved as-sintered surface or a small hole with an as-sintered interior peripheral surface, or has a three-dimensionally curved polished surface obtained by polishing an as-sintered surface. The watch exterior part is manufactured by a method in which organic binder is milled into a material powder, and a molded body obtained by injection molding is subjected to a binder removing process and then sintered. By the manufacturing method, a watch exterior part formed of cemented carbide or stellite alloy has a high strength and a complicated configuration such as a three-dimensional curved surface and a small hole, without applying secondary machining operations such as discharge operations.
    Type: Grant
    Filed: May 28, 1992
    Date of Patent: April 4, 1995
    Assignees: Sumitomo Electric Industries, Ltd., Namiki Precision Jewel Co., Ltd.
    Inventors: Nobuyuki Kitagawa, Toshio Nomura, Yoichi Yaguchi, Hidehiro Uchiumi, Naoko Iwashimizu