Patents Represented by Attorney, Agent or Law Firm Randall Bluestone
  • Patent number: 6560057
    Abstract: A disk drive includes a read/write head mounted on an actuator, a disk having an inner diameter region and an outer diameter region, the head being radially movable by the actuator between the inner diameter region and the outer diameter region. An unload ramp is positioned at the outer diameter region. A controller outputs control signals upon sensing a power down condition. A feedback circuit is adapted to sense a back emf generated by the actuator and to use the back emf to apply a counter-acting voltage to the actuator that tends to bring the actuator to a stop. A switch is responsive to the control signals to (i) connect the feedback circuit to the actuator to enable the actuator to be brought to a stop while the disk continues to rotate and (ii) for then causing the actuator to move the head to the unload ramp. The switch further applies a voltage which causes the actuator to bring the head to the inner diameter region of the disk, before causing the actuator to move the head to the unload ramp.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: May 6, 2003
    Assignee: International Business Machines Corporation
    Inventors: Erno Hilbrand Klaassen, Bryan Scott Rowan