Patents by Inventor Kazuhiko Sumiya

Kazuhiko Sumiya 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).

  • Magnetic disk system having tracking control using recorded information
    Patent number: 5070421
    Abstract: A magnetic disk system comprises: a magnetic disk in which servo information is stored deeply in the appropriate fields Es longitudinally separated from the data field ED into which information of each track is stored; a subhead provided at a position ahead of the main head in a direction of data writing through the main head, the subhead being in a unitary construction with the main head and having a wider gap than the main head; a tracking control means for controlling the position of the main head relative to the desired track on the basis of the servo information SD that is read by means of the subhead for erasing information at the data field ED by means of the subhead prior to data writing by the main head in the data field ED; and a switch means for shifting the switch to tracking control means or to information erasing means.
    Type: Grant
    Filed: May 6, 1991
    Date of Patent: December 3, 1991
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Kazuhiko Sumiya, Hajime Sugino