Patents by Inventor Kazuo Ohya

Kazuo Ohya 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: 4416709
    Abstract: The present invention relates to an amorphous magnetic alloy material suited for use as a core material of a magnetic head.When the magnetic head is subjected to a slide contact with a magnetic tape over a long period of time, a film of oxide and the like is formed on the surface of an amorphous magnetic alloy material due to chemically corrosive media frequently contained in the magnetic coating layer of the magnetic tape or due to carbon dioxide, water and the like contained in the air.The amorphous magnetic alloy material of the present invention is highly corrosion resistant due to the combination of chromium and platinum family element(s), and, the inconveniences in a magnetic head, due to chemical wear, can be prevented even where the magnetic head is operated or stored in a considerably severe condition.
    Type: Grant
    Filed: September 10, 1981
    Date of Patent: November 22, 1983
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Kazuo Ohya, Hiroki Fujishima, Norio Ishijima, Hiroyoshi Itoga, Yasuhiko Kominami
  • Patent number: 4188211
    Abstract: During investigation of thermal stability of the amorphous magnetic alloys by the Inventors, it was discovered that, due to the application of heat to the alloys, the hysteresis loop of the conventional, amorphous magnetic alloys was shifted in such a manner that the initial permeability of the alloys was decreased. It was also discovered that the initial permeability of the conventional amorphous magnetic alloys was irreversibly changed due to the application of heat to and the withdrawal of heat from the alloys.The present invention is characterized by the discovery of an unexpected relationship between the content of metallic elements and a metalloid element(s) of the amorphous alloy composition, thereby providing novel alloy compositions with thermally stable magnetic properties.The present invention is also characterized by incorporating an additional element or elements into an amorphous magnetic alloy, thereby providing the alloy with thermal stability.
    Type: Grant
    Filed: February 9, 1978
    Date of Patent: February 12, 1980
    Assignee: TDK Electronics Company, Limited
    Inventors: Norishige Yamaguchi, Kazuo Ohya, Osamu Kohmoto, Hiroki Fujishima
  • Patent number: 4079430
    Abstract: Amorphous metal alloys are employed in a magnetic head as core materials in the present invention. Such alloys are generally composed of M and Y, wherein M is at least one of Fe, Ni and Co and Y is at least one of P, B, C and Si. The amorphous metal alloys used are marked by a combination of the desirable properties of conventional permalloy with those of conventional ferrites.
    Type: Grant
    Filed: February 10, 1976
    Date of Patent: March 14, 1978
    Assignee: TDK Electronics, Co., Ltd.
    Inventors: Hiroki Fujishima, Kazuo Ohya