Patents by Inventor James J. Ng

James J. Ng 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).

  • Data storage device employing balanced current drive to unload multiple voice coil motors
    Patent number: 9997182
    Abstract: A data storage device is disclosed comprising a first voice coil motor (VCM) comprising a first voice coil configured to actuate a first head over a first disk, a second VCM comprising a second voice coil configured to actuate a second head over a second disk, and a spindle motor configured to rotate the first and second disk, wherein during a power failure the first and second disks rotating causes the spindle motor to generate a back electromotive force (BEMF) voltage. During the power failure the first and second VCMs are unloaded, wherein during a first interval the first voice coil is connected to the BEMF voltage and the second voice coil is disconnected from the BEMF voltage, and during a second interval the second voice coil is connected to the BEMF voltage and the first voice coil is disconnected from the BEMF voltage.
    Type: Grant
    Filed: November 9, 2017
    Date of Patent: June 12, 2018
    Assignee: Western Digital Technologies, Inc.
    Inventors: Brian K. Tanner, James J. Ng