Patents by Inventor Daniel L. Griffith

Daniel L. Griffith 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: 5452153
    Abstract: A magnetic recording head positioning system includes a Terfenol-D magnetostrictive rod prestressed by a lever arm to operate in a linear range to microposition the magnetic recording head in accordance with an electromagnetic field. The mechanical advantage of the lever arm amplifies changes in the magnetostrictive rod to position the head. The varying electromagnetic field is applied to the rod by a coil in response to a position error signal produced from servo data tracks on the magnetic tape. A permanent magnet system biases the magnetostrictive element with a DC field so that varying the field provides bi-directional motion of the magnetic recording head. The DC field also reduces coil current and size requirements.
    Type: Grant
    Filed: July 19, 1994
    Date of Patent: September 19, 1995
    Assignee: Wangtek, Inc.
    Inventors: Hamid Baheri, Peter Campbell, Daniel L. Griffith, Jefferson H. Harman