Patents by Inventor Robert T. Bradbury

Robert T. Bradbury 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: 6671121
    Abstract: An information handling system, such as a disc drive, includes a base, a disc stack rotatably attached to the base, and an actuator assembly movably attached to the base, with multiple movable mill-actuator arms mounted on one portion of the actuator assembly. Attached to an end of the actuator is a voice coil which forms a portion of a voice coil motor. Magnets attached to the base form the other portion of the voice coil motor. A current driver for the voice coil delivers an amount of current to the voice coil to move the actuator assembly. Attached to another end of the actuator assembly is one or more transducers. In order to minimize the disturbance of a seeking milli-actuator, the operation to be executed is to cause the first milli-actuator to return slowly to its rest or zero position. A rate of return control circuit is implemented to drive a milli-actuator such that a milli-actuator at a non-zero or non-rest position will be returned to a rest position at a rate slower than a seeking milli-actuator.
    Type: Grant
    Filed: August 23, 2000
    Date of Patent: December 30, 2003
    Assignee: Seagate Technology LLC
    Inventors: Robert T. Bradbury, Travis E. Ell
  • Patent number: 6249064
    Abstract: Apparatus and method for providing microactuator positional control in a disc drive having a rotatable disc on which a plurality of tracks are defined and an actuator assembly which supports a head adjacent the tracks. An actuator motor is used to provide primary positioning of the head through the controlled application of current to a coil of the actuator motor. A microactuator, opposite the actuator motor coil, has a pair of microactuator coils wound about respective magneto-striction beams so that, in response to drive currents passed through the microactuator coils, a selected one of the magneto-striction beams increases in length and the remaining magneto-striction beam decreases in length. The magneto-striction beams act upon a pivot assembly coupled to the head to displace the head to a final desired position adjacent the disc.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: June 19, 2001
    Assignee: Seagate Technology LLC
    Inventor: Robert T. Bradbury