Patents by Inventor Kazumine Ito

Kazumine Ito 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: 4785444
    Abstract: An optical recording disc in which a disc substrate made of a synthetic resin having a light transmittance and a hub made of a synthetic resin, fixed to a center part of the disc substrate by means of a predetermined technique such as a supersonic wave expansion molding and on which a circular magnetic metal plate is installed by means of an insert molding and so on are provided and a circular groove which is continuous at an outer peripheral side of a fixing part between the disc substrate and hub is furthermore installed on at least either of the disc substrate or hub. The groove is provided for absorbing a stress generated due to a difference in thermal expansion rates between the disc substrate made of the snythetic resin and magnetic metal plate.
    Type: Grant
    Filed: February 20, 1987
    Date of Patent: November 15, 1988
    Assignee: Sony Corporation
    Inventors: Yasuaki Nakane, Kazumine Ito, Sanae Abe, Takashi Naito