Patents Represented by Attorney, Agent or Law Firm W. Chris Kim, Esq.
  • Patent number: 6560065
    Abstract: A disk drive includes a disk drive base. The disk drive further includes at least one rotatable disk including a disk surface extending to an outer disk edge. The disk drive further includes a head stack assembly rotatably attached to the disk drive base in operable communication with the disk. The disk drive further includes an airflow suppressor comb coupled to the disk drive base and stationary relative to the disk drive base during operation of the disk drive. The comb includes a comb body disposed adjacent to the outer disk edge, and at least one tine extending from the comb body along the disk surface for mitigating disk rotation induced airflow upon the head stack assembly adjacent to the disk surface. The comb further includes a curved extension extending along the outer disk edge for mitigating turbulent airflow adjacent the outer disk edge.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: May 6, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Lin Yang, Jin Hui Ou-Yang
  • Patent number: 6549381
    Abstract: A disk drive includes a disk having a recording surface and a head stack assembly that includes an actuator body; an actuator arm cantilevered from the actuator body and including a head for reading and writing on the recording surface; a coil cantilevered from the actuator body in an opposite direction from the actuator arm, the coil defining a first leg and a second leg and a damping magnet disposed between the first and second legs. The damping magnet is configured to exert a damping force on the head stack assembly that is greater when the head is at a predetermined non-operational position than when the head is over the recording surface.
    Type: Grant
    Filed: October 23, 2001
    Date of Patent: April 15, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Scott E. Watson
  • Patent number: 6545382
    Abstract: An aspect of the invention can be regarded as a spindle motor. The spindle motor includes a rotor and a stator. The rotor includes a first plate defining a circular first plate periphery disposed about a central axis, a second plate defining a circular second plate periphery disposed about the central axis, and a magnet defining a circular periphery disposed about the central axis between and parallel to the first and second plates. The stator includes a plurality of magnetic flux guides distributed radially about the rotor.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: April 8, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: George J. Bennett
  • Patent number: 6535358
    Abstract: A disk drive is disclosed comprising a base, a disk, an actuator arm comprising a tang attached to a base end of the actuator arm, a head attached to a distal end of the actuator arm, a voice coil motor for rotating the actuator arm about a pivot to position the head radially over the disk, and a crash stop comprising injection molded plastic formed into a body piece having a protruding first arm and a protruding second arm. The body piece of the crash stop is attached to the base of the disk drive. The first protruding arm comprises a magnet at least partially embedded into the plastic for latching the tang of the actuator arm to the first protruding arm. The plastic is formed around the magnet such that at least part of the plastic is between the magnet and the tang. The second protruding arm presents a physical barrier to the tang to limit the stroke of the actuator arm.
    Type: Grant
    Filed: November 30, 2000
    Date of Patent: March 18, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Serge Hauert, Scott E. Watson
  • Patent number: 6534936
    Abstract: A disk drive is connectable to a power supply voltage and includes a spindle motor, a spindle motor driver, a spindle motor controller, and a detector. The spindle motor has windings and a rotatable rotor. The spindle motor driver is connected to the windings and connectable to the voltage. The spindle motor controller commands the spindle motor driver to apply the voltage across at least one of the windings to cause the rotor to rotate, which induces a BEMF having a polarity across each of the windings.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: March 18, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Carl R. Messenger, Russ A. Quisenberry
  • Patent number: 6529351
    Abstract: A disk drive is disclosed comprising an actuator arm, a head coupled to the actuator arm, and a voice coil motor for actuating the actuator arm to move the head. The voice coil motor comprises a first magnet for generating a first magnetic flux, and a yoke comprising a magnetic flux conductor for guiding the first magnetic flux. The magnetic flux conductor comprises a body and a top and bottom protruding plate portions, wherein the body and the plate portions are integrally formed. The body defines, in vertical cross section, a primary bend having a primary bend radius and at least one secondary bend having a secondary bend radius.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: March 4, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Kamran Oveyssi, Mitchell D. Dougherty
  • Patent number: 6522504
    Abstract: A disk drive includes a head gimbal assembly and a disk that includes a recording surface. The head gimbal assembly comprises a load beam, the load beam including a first load beam surface facing toward the recording surface and a second load beam surface facing away from the recording surface, a plurality of conductors at least partially supported by the first load beam surface, each conductor including a proximal conductive pad, a distal conductive pad and a conductive path between the proximal and distal conductive pads, the proximal conductive pad being closer to a pivot axis than the distal conductive pad, a gimbal coupled to the load beam, the gimbal including a gimbal proximal end that supports the respective distal conductive pads and a gimbal distal end, and a head for flying above the recording surface of the disk while reading magnetic data recorded on the recording surface of the disk as the disk spins in a rotational direction.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: February 18, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Shawn E. Casey
  • Patent number: 6519116
    Abstract: An aspect of the invention can be regarded as an actuator arm assembly which includes an actuator arm having an actuator bore. The actuator arm is configured to pivot about an axis of rotation. The actuator bore has pivot sleeve contact areas. The actuator arm assembly includes a pivot cartridge which includes a pivot sleeve which is formed to exert compressive force radially from the axis of rotation. The pivot sleeve is formed to locally deform radially relative to the axis of rotation adjacent the pivot sleeve contact areas. The pivot cartridge includes a bearing outer race. The pivot cartridge includes a bearing gap formed between the bearing outer race and the pivot sleeve for inhibiting transfer of force between the pivot sleeve and the bearing outer race.
    Type: Grant
    Filed: November 30, 2000
    Date of Patent: February 11, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Chen-Chi Lin, Kamran Oveyssi, Shawn E. Casey
  • Patent number: 6502300
    Abstract: An aspect of the invention can be regarded as a method of balancing a rotary actuator for use in a rotatable head stack assembly (HSA) portion in a disk drive. The rotary actuator has a pivot axis, and the rotatable HSA portion has an installed HSA portion center-of-gravity. The method provides for deetermining a desired rotary actuator center-of-gravity location for locating the installed HSA portion center-of-gravity along the pivot axis for mitigating acceleration of the rotary actuator about the pivot axis due to external linear acceleration experienced by the disk drive during a track-follow operation. The method further provides for measuring weight distribution characteristics of the rotary actuator to determine an actual rotary actuator center-of-gravity. The method further provides for selectively modifying weight distribution characteristics of the rotary actuator to locate the actual rotary actuator center-of-gravity at the desired rotary actuator center-of-gravity location.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: January 7, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Shawn E. Casey, Raffi Codilian, Roger G. Davis, Jorge Haro
  • Patent number: 6469871
    Abstract: A disk drive is disclosed comprising a bistable latch for latching an actuator arm in a latched position. The bistable latch comprises a latch base comprising a first groove and a second groove, wherein a depth of at least part of the first groove is different than a depth of at least part of the second groove. The bistable latch further comprises a latch arm movable with respect to the latch base, the latch arm comprising a guide member interacting with the first and second grooves for guiding the latch arm through a predetermined trajectory. The bistable latch further comprises a spring having a first end connected to the latch base and a second end connected to the latch arm.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: October 22, 2002
    Assignee: Western Digital Technologies, Inc.
    Inventor: David T. W. Wang
  • Patent number: 6466398
    Abstract: A disk drive is disclosed with reduced resonance. The disk drive comprises a disk, a fixed spindle shaft disposed axially through the disk, a spindle motor for rotating the disk about the fixed spindle shaft, wherein a resonance is associated with the spindle motor rotating the disk. The disk drive further comprises a head, an actuator arm for actuating the head radially over the disk, a base, and a cover attached to the base to form a head disk assembly chamber. The cover comprises a shaft aperture positioned over the fixed spindle shaft, the shaft aperture for receiving a fastener for attaching the cover to the fixed spindle shaft. The cover further comprises a plurality of slots proximate the shaft aperture, wherein the shaft aperture and slots provide a flexible support for the fixed spindle shaft which reduces the resonance associated with the spindle motor.
    Type: Grant
    Filed: September 30, 2000
    Date of Patent: October 15, 2002
    Assignee: Western Digital Technologies, Inc.
    Inventors: Walter W. Butler, Gregory G. Foisy, John R. Gustafson
  • Patent number: 5824898
    Abstract: A system for balancing devices having motors and rotating masses to be coupled to the motors utilizes a momentum transfer mechanism to shift the rotating mass based on sensed imbalance. In this manner the mass is shifted to a position which accounts for the inherent imbalance in both the motor and the mass. A controller receives imbalance information from a velocity sensor and controls a solenoid to strike a base coupled to the motor to shift a lightly clamped mass relative to the motor. In one embodiment, a disk drive has disks initially biased by the system against a hub, and then shifted during rotation to create a disk drive having concentrically aligned disks offsetting imbalance inherent in a motor used to rotate the disks. In one embodiment, the disks are held to the hub by a clamp having screws. The screws are driven simultaneously through the same angle of rotation to ensure that the axial clamping force of each one is substantially equal.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: October 20, 1998
    Assignee: Western Digital Corporation
    Inventors: Peter E. Brooks, Lance A. Gabrielson