Patents by Inventor Nobumitsu Oshimura

Nobumitsu Oshimura 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).

  • Process for preparing powder of an alloy of a rare earth element, iron and boron for a resin bonded magnet
    Patent number: 4944801
    Abstract: A powder of a rare earth oxide, or a powder of a rare earth oxide and a rare earth metal is mixed with a powder containing iron, a powder containing boron and at least one material selected from among an alkali metal, an alkaline earth metal and a hydrogenated product thereof. The mixture is heated at a temperature of 900.degree. C. to 1200.degree. C. in a non-oxidizing atmosphere, subjected to wet treatment, and heated again at a temperature of 650.degree. C. to 1100.degree. C., whereby an alloy powder is obtained. Alternatively, the mixture is heated at a temperature of 900.degree. C. to 1200.degree. C., crushed into coarse particles, heated again at a temperature of 650.degree. C. to 1100.degree. C. and subjected to wet treatment. The powder is pulverized into a finer powder having an average particle diameter of 1 to 10 microns. The powder is used for making a magnet with a resin.
    Type: Grant
    Filed: July 5, 1989
    Date of Patent: July 31, 1990
    Assignee: Sumitomo Metal Mining Co. Ltd.
    Inventors: Takashi Ishikawa, Nobumitsu Oshimura, Kenji Ohmori