Patents Represented by Attorney Chris Kim
  • Patent number: 5790348
    Abstract: A disk drive includes an enclosure having a base, a spindle motor fixed to the base, a disk mounted on the spindle motor, a pivot bearing cartridge, and a head stack assembly. The pivot bearing cartridge includes a shaft fixed to the enclosure, and the head stack assembly is connected to the pivot bearing cartridge for rotation relative to the shaft. The head stack assembly includes a body portion having a bore which surrounds the pivot bearing cartridge, a plurality of actuator arms with each arm cantilevered from the body portion, and a coil portion. The coil portion is cantilevered from the body portion in an opposite direction from the plurality of arms and provides damping of vibrations induced in the head stack assembly. The coil portion includes a plastic portion having a thickness, and a coil embedded in the plastic portion. The plastic portion includes a plurality of openings where each opening extends through the entire thickness of the plastic portion.
    Type: Grant
    Filed: July 22, 1997
    Date of Patent: August 4, 1998
    Assignee: Western Digital Corporation
    Inventors: Steven Alfred, Gordon A. Harwood, Marvin A. Schlimmer
  • Patent number: 5781380
    Abstract: The invention relates to a magnetic disk drive having a head stack assembly including a rotary actuator body having a flex circuit mounting site for mounting a main actuator flex circuit and an arm extending therefrom which supports a head gimbal assembly (HGA). The invention provides for molding the conductors into the arm and the actuator body so that the conductors are strategically exposed along the flex circuit mounting side of the actuator body and along an end of the arm body which mates with the HGA.
    Type: Grant
    Filed: April 1, 1997
    Date of Patent: July 14, 1998
    Assignee: Western Digital Corporation
    Inventors: Keith R. Berding, Shawn E. Casey, Charles B. Mountain
  • Patent number: 5781373
    Abstract: A noise suppression system for use in a disk drive. The system isolates the interface between the disk drive cover and the moving parts of the disk drive to attenuate acoustic energy introduced by the moving parts and also dissipates some of the unwanted acoustic energy in viscoelastic damping layers. An outer plate made of a rigid layer covered with a viscoelastic damping layer is disposed over an inner cover in which is provided an open region surrounding the pivot axis of the head-stack assembly (HSA) or, alternatively, surrounding both the pivot axis and the spindle axis of the disk assembly. A rigid interface member is fixed to the pivot journal or, alternatively, to both the pivot journal and the spindle journal within the open region. The outer plate is fitted to the periphery of the inner cover so that the viscoelastic damping layer abuts a flexible sealing member fitted over the interface member and inner cover around the open region.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: July 14, 1998
    Assignee: Western Digital Corporation
    Inventors: Nils Eric Larson, Ajit Fathailal Sancheti
  • Patent number: 5768061
    Abstract: A head stack assembly for a disk drive includes a swing-type structure, a head gimbal assembly, and a coil. The swing-type structure has a bore defining a bore axis. The head gimbal assembly is cantilevered from the swing-type structure to project radially away from the bore axis. The head gimbal assembly includes transducing structure for writing to and reading from the recording surface of a disk. The coil is cantilevered from the swing-type structure to project radially away from the bore axis in a direction opposite from the head gimbal assembly. The coil has a shape to provide a current flow path that includes first and second multi-leg portions that are spaced from each other in a direction parallel to the bore axis.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: June 16, 1998
    Assignee: Western Digital Corporation
    Inventors: Shawn Casey, Mats Anders Engwall, Martin John McCaslin
  • Patent number: 5757588
    Abstract: A head disk assembly for a hard disk drive employs a rotary actuator apparatus including a pivot shaft that defines an actuator axis of rotation. A pivot bearing assembly including a pivot bushing having a plurality of fingers supports rotation of the actuator about the pivot shaft. Each of a plurality of fingers has a bearing end that is in sliding contact with the pivot shaft. The fingers are formed from a material in a shape that provides the stiffness and low coefficient of friction necessary for the desired pivot bearing performance.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: May 26, 1998
    Assignee: Western Digital Corporation
    Inventor: Nils E. Larson
  • Patent number: 5751514
    Abstract: An intelligent hard disk drive, which includes a head disk assembly (HDA) and a printed circuit board assembly (PCBA), has a thin configuration. The HDA includes a spindle motor and the PCBA includes spindle motor driver circuitry. Spring loaded contacts and exposed electrical contacts provide automatic electrical connection between the spindle motor and the spindle motor driver circuitry.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: May 12, 1998
    Assignee: Western Digital Corporation
    Inventors: Darryl L. Hyde, John R. Edwards
  • Patent number: 5751517
    Abstract: An air bearing slider having debris removing channels for a hard disk drive. An air bearing slider contains a center pad having multiple longitudinal debris channels cut therein approximately 1-3 microns wide and approximately 1-3 microns deep and spanning the entire length of the air bearing surface of the center pad. The debris channels are effective for collecting small sized debris and passing them through the channel length and out the trailing end of the center pad. By this action, the debris are prevented from collecting along the edges, corners and on the top surface of the center pad or on and around the transducer situated on the center pad. By reducing debris in these locations, the debris does not alter the flying height of the slider with respect to the surface of the disk. Therefore, by eliminating debris around the transducer, this invention eliminates errors caused by the debris and thereby provides a more reliable disk drive.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: May 12, 1998
    Assignee: Western Digital Corporation
    Inventor: Shashi B. Agarwal
  • Patent number: 5731934
    Abstract: A head disk assembly ("HDA") comprises an enclosure including a base and a pivot bearing cartridge having a shaft and a outer shell rotatable about the shaft. The outer shell has a cylindrical surface. The shaft is affixed to the base at a predetermined location. The enclosure has an internal volume with a limited height above the predetermined location. The cartridge has an elongated portion in the volume, the elongated portion having a height approximately equal to the limited height. The HDA further comprises a plurality of rotating disks, each having at least one recording surface. The HDA further comprises an arm stack comprising a plurality of arms, and a plurality of head gimbal assemblies. Each arm has a stacking portion and a cantilever portion. Each head gimbal assembly has one end attached to the cantilever portion of a respective arm and has an opposite end positioned adjacent a recording surface.
    Type: Grant
    Filed: April 10, 1997
    Date of Patent: March 24, 1998
    Assignee: Western Digital Corporation
    Inventors: Peter Everett Brooks, Gerald Daniel Malagrino, Jr., Jeffrey Eric Mason
  • Patent number: 5727882
    Abstract: A pivot bearing assembly for mounting to an enclosure of a head disk assembly to support a head stack assembly of a disk drive is disclosed. The pivot bearing assembly comprises a shaft for being affixed to the enclosure and defining a longitudinal axis, a first and second set of bearings, the second set of bearings longitudinally spaced from the first set of bearings, and each set of bearings surrounding a respective portion of the shaft. The pivot bearing assembly also comprises an inner sleeve member and an outer sleeve member, both sleeve members surrounding the shaft. A pair of channels is located between the outer and inner sleeve members. Alternatively, the pair of channels is located between the shaft and the sets of bearings. The channels contain a cured cast-in-place material, preferably, an ultra violet cured polyurethane compound having a hardness between approximately 24 Shore A to 79 Shore A.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: March 17, 1998
    Assignee: Western Digital Corporation
    Inventors: Walter Wayne Butler, John Robert Edwards
  • Patent number: 5675456
    Abstract: A vibration decoupler for a swing-type head actuator pivot bearing assembly in a disk drive. The invention selectively decouples axial actuator vibrations from the pivot shaft while retaining the radial and rotational rigidity needed to ensure head positioning precision. The head stack assembly is rigidly coupled to the pivot bearing shaft in the radial and rotational dimensions and is pliably coupled to the same shaft in the axial dimension. This decoupling scheme eliminates most acoustic vibration components created in the rotary actuator. Axial decoupling eliminates most acoustic vibration components transmitted from the pivot shaft to the drive housing. The vibration isolator may be fabricated as a single piece of injection-molded plastic, including all necessary elements for coupling to the pivot bearing and the actuator body.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: October 7, 1997
    Assignee: Western Digital Corporation
    Inventor: David K. Myers