Patents by Inventor Morifumi Ohsawa

Morifumi Ohsawa 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).

  • Disk drive device equipped with a bearing unit relatively rotatably supporting a hub against base member
    Patent number: 8345379
    Abstract: A disk drive device has a hub so configured as to place and hold recording disks. Where the non-rotating eigenfrequency of resonance in a secondary rocking mode with the recording disks placed on the hub is defined to be F0 (Hz) and the rotational frequency of the hub is defined to be N (Hz), an extending part of the hub and a second cylinder part of the hub are formed such that the radial dimension of the extending part is smaller than the axial dimension of the second external cylinder part to satisfy to a relation F0>N·(3·P+2).
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: January 1, 2013
    Assignee: Alphana Technology Co., Ltd.
    Inventors: Toshiki Maeda, Kazuhide Kamata, Morifumi Ohsawa
  • DISK DRIVE DEVICE EQUIPPED WITH A BEARING UNIT RELATIVELY ROTATABLY SUPPORTING A HUB AGAINST BASE MEMBER
    Publication number: 20110116191
    Abstract: A disk drive device has a hub so configured as to place and hold recording disks. Where the non-rotating eigenfrequency of resonance in a secondary rocking mode with the recording disks placed on the hub is defined to be F0 (Hz) and the rotational frequency of the hub is defined to be N (Hz), an extending part of the hub and a second cylinder part of the hub are formed such that the radial dimension of the extending part is smaller than the axial dimension of the second external cylinder part to satisfy to a relation F0>N·(3·P+2).
    Type: Application
    Filed: August 31, 2010
    Publication date: May 19, 2011
    Applicant: ALPHANA TECHNOLOGY CO., LTD.
    Inventors: Toshiki MAEDA, Kazuhide KAMATA, Morifumi OHSAWA