Patents by Inventor Toshiki Matsui

Toshiki Matsui 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).

  • Corrosion resistant permanent magnet
    Patent number: 4942098
    Abstract: To obtain an anticorrosive Fe-B-R type permanent magnet; in particular, to reduce deterioration rate of the initial magnetic properties below 10% after the magnet has been kept at 80.degree. C. in 90% relative humidity for 500 hours, the surface of the sintered permanent magnet is coated with metallic coating film layers of at least one noble metal layer and at least one base metal layer disposed on the noble metal layer. Diffusion heat treatment further improves the adhesiveness of the coating film layers.
    Type: Grant
    Filed: March 24, 1988
    Date of Patent: July 17, 1990
    Assignees: Sumitomo Special Metals, Co., Ltd., Toda Kogyo Corp.
    Inventors: Atsushi Hamamura, Takaki Hamada, Hiroko Nakamura, Tomoyuki Imai, Toshiki Matsui, Nanao Horiishi