Patents by Inventor Mashiro Oita

Mashiro Oita 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: 4141727
    Abstract: An electrical contact material comprising silver, bismuth oxide and tin oxide with or without tin metal, wherein the amounts of the bismuth and the tin on the basis of the sum weight of the metals in both the metal component and in the metal oxide component are 1.5 to 6 weight percent and 0.1 to 6 weight percent, respectively. This electrical contact material has high resistance to both welding and arc erosion. An advantageous method of making the electrical contact material comprises preparing a metal alloy composed of all the above metals in the above weight ratio and internally oxidizing the bismuth completely in the alloy after shaping the alloy to a desired electrical contact material shape or after crushing the alloy to scaly flakes.
    Type: Grant
    Filed: November 29, 1977
    Date of Patent: February 27, 1979
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Sankichi Shida, Shinji Okuma, Mashiro Oita, Hyogo Hirohata