Patents Represented by Attorney, Agent or Law Firm Howard H. Sheerin
  • Patent number: 6687078
    Abstract: The present invention may be regarded as a disk drive comprising a disk having a plurality of data tracks and at least one reserved track. At least one of the data tracks for recording user data along a circumferential path offset from the centerline of the data track, and the at least one reserved track for recording data track micro-jog values along a circumferential path substantially aligned with the centerline of the reserved track.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: February 3, 2004
    Assignee: Western Digital Technologies, Inc.
    Inventor: Yoo H. Kim
  • Patent number: 6661591
    Abstract: A disk drive is disclosed comprising a disk, a head, and an actuator for actuating the head radially over the disk. The disk comprises a plurality of tracks, each track comprises a plurality of data sectors for storing data and a plurality of sector-reconstruction-interleave (SRI) sectors for storing redundancy data. The redundancy data stored in a selected one of the SRI sectors is generated in response to the data stored in an interleave of the data sectors corresponding to the selected one of the SRI sectors.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: December 9, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Michael S. Rothberg
  • Patent number: 6657810
    Abstract: A disk drive is disclosed comprising a disk having a plurality of tracks, each track comprising a plurality of data sectors for storing user data and a plurality of embedded servo sectors for storing servo data. The disk drive further comprises a head comprising a read element and a write element, wherein the read element is offset from the write element. The disk drive stores a plurality of read repeatable runout (RRO) estimated values and a plurality of write RRO estimated values which are introduced into a servo loop to compensate for the different RRO disturbances which manifest during read and write operations.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: December 2, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Hanan Kupferman
  • Patent number: 6654193
    Abstract: A disk drive is disclosed which detects a defective servo sector during a write operation and identifies a defective range of data sectors associated with the defective servo sector. A block relocation procedure is executed to identify a plurality of data sectors within the defective range and to relocate the plurality of data sectors to spare data sectors outside of the defective range.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: November 25, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Gregory B. Thelin
  • Patent number: 6639748
    Abstract: The present invention may be regarded as a disk drive comprising a disk having a plurality of data tracks, each data track comprising a plurality of sectors. A sync mark detector detects a sync mark pattern in a sector, wherein when the sync mark pattern is detected a sync mark detect signal and a polarity signal are generated. The polarity signal represents an expected polarity of pulses in a read signal representing data stored in the sector, wherein the polarity signal enhances the detection of an estimated data sequence from the read signal.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: October 28, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Grant S. Christiansen, Mark D. Hagen
  • Patent number: 6624980
    Abstract: A disk drive is disclosed comprising a disk, an actuator arm, a head attached to the actuator arm, a voice coil motor, a parking latch for latching the actuator arm in a latched position in order to park the head during a non-operating mode, and a flex circuit having a first end and a second end, the first end coupled to the actuator arm. The disk drive further comprises an inertial latch for maintaining the actuator arm in the latched position when the disk drive is subjected to a physical shock. The inertial latch comprises a body having a protruding arm and defining a pivot axis. The inertial latch further comprises a support member coupled to the base, the support member comprising a connecting surface for connecting to the second end of the flex circuit, and a restraining member connected to the body of the inertial latch proximate the pivot axis, wherein the restraining member vertically restrains the inertial latch.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: September 23, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Scott E. Watson, Serge Hauert
  • Patent number: 6611393
    Abstract: A disk drive is disclosed which calibrates at least one zone parameter in the field. During an active state of the disk drive, read errors are detected and corresponding entries are stored in an error list. During an off-line state, the error list is processed in order to calibrate at least one zone parameter.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: August 26, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Phat T. Nguyen, Yoo H. Kim, Albert W. Briggs
  • Patent number: 6606714
    Abstract: A disk drive is disclosed for receiving a write command from a host computer, the write command comprising a plurality of logical block addresses (LBAs) and a plurality of data blocks. The plurality of data blocks comprises at least one non-relocated data block (NRDB) and at least one relocated data block (RDB), and at least one of the LBAs corresponds to the NRDB and at least one of the LBAs corresponds to the RDB. The disk drive comprises a disk comprising a plurality of first disk locations each having a defect, a plurality of second disk locations for storing NRDBs, and a plurality of spare disk locations for storing RDBs. A defect list is used to map LBAs from the plurality of first disk locations to the plurality of spare disk locations. A cache is logically partitioned into a first set of memory locations managed using a first cache data structure, and a second set of memory locations managed using a second cache data structure.
    Type: Grant
    Filed: April 17, 2000
    Date of Patent: August 12, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Gregory B. Thelin
  • Patent number: 6603620
    Abstract: A mobile device is disclosed comprising a disk storage system including a disk and a head actuated over the disk, wherein the disk comprises a data area. The mobile device further comprises a motion detector for detecting a relative velocity and distance of a foreign object with respect to the mobile device. When the motion detector detects an impending impact with the foreign object, retracting circuitry within the mobile device retracts the head away from the data area of the disk.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: August 5, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Keith R. Berding
  • Patent number: 6603625
    Abstract: A multi-dimensional computer network is disclosed comprising a multi-dimensional network controller for interconnecting a plurality of computer devices, including a plurality of disk drives, communicating via a network protocol through a plurality of nodes, each node comprising more than two bi-directional ports for simultaneously transmitting data in multiple dimensions through the multi-dimensional computer network. At least one of the disk drives comprises a disk for storing data and an index mark, a spindle motor for rotating the disk, a head for reading the data and the index mark stored on the disk, an index mark detector for generating an index mark detect signal in response to the head reading the index mark, an interface for receiving a spindle sync signal from the multi-dimensional network controller through the network protocol, and a spindle synchronization circuit, responsive to the index mark detect signal, for synchronizing the rotation of the disk to the spindle sync signal.
    Type: Grant
    Filed: September 11, 2000
    Date of Patent: August 5, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Andrew D. Hospodor, Christopher L. Hamlin
  • Patent number: 6604220
    Abstract: A disk drive is disclosed comprising a multiple-input sequence detector for detecting an estimated data sequence from a sequence of read signal sample values. The multiple-input sequence detector comprises a first iterative detector and a second iterative detector. An error correction code (ECC) decoder decodes the estimated data sequence into at least one decoded codeword comprising a plurality of bits which are used as reliability metrics for biasing at least one of the iterative detectors.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: August 5, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Patrick J. Lee
  • Patent number: 6603622
    Abstract: The present invention may be regarded as a disk drive comprising a disk having a plurality of data tracks, each data track comprising a plurality of sectors. A sync mark detector detects a sync mark pattern in a sector by filtering a read signal with a matched filter having an impulse response substantially matched to a dibit response of the disk drive. The output of the matched filter is correlated with a dual polarity correlator to generate first and second correlated signals. The sync mark pattern is detected when either the first or second correlated signals exceeds a threshold.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: August 5, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Grant S. Christiansen, Mark D. Hagen
  • Patent number: 6600620
    Abstract: The present invention may be regarded as a self-servo writing disk drive comprising a head having a read element radially offset from a write element. During a first time interval, the read element is positioned over a first radial location to read first A clock data to generate first circumferential timing information and first A servo bursts to generate first position control information. The first position control information is used for positioning the write element over a second radial location, and the first circumferential timing information is used for writing second B clock data and second B servo bursts to the second radial location. During a second time interval, the read element is positioned over the first radial location to read first B clock data to generate second circumferential timing information and first B servo bursts to generate second position control information.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: July 29, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Mohamad T. Krounbi, John Cuda, Jack M. Chue, Robert Leslie Cloke, David Price Turner, Gary L. Dunbar
  • Patent number: 6580574
    Abstract: A mobile device is disclosed comprising a disk storage system comprising a disk and a head actuated over the disk, the disk comprising a data area. The mobile device further comprises a pressure-sensitive detector for detecting a pressure on the mobile device, and for detecting a decrease in the pressure on the mobile device indicating the mobile device may have been dropped. When the pressure-sensitive detector detects the decrease in the pressure, retracting circuitry within the mobile device retracts the head to a retracted position away from the data area of the disk.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: June 17, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Raffi Codilian
  • Patent number: 6574073
    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: January 31, 2003
    Date of Patent: June 3, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Serge Hauert, Scott E. Watson
  • Patent number: 6568268
    Abstract: A multi-axis accelerometer is disclosed comprising at least one optical sensor for generating a sensor signal in response to light illuminating the optical sensor, a mask positioned over the optical sensor for covering a first area of the optical sensor, at least one spring, and a mass suspended above the optical sensor by the spring. The mass comprises at least one mass aperture for allowing the light to pass through the mass aperture and illuminate a second area of the optical sensor not covered by the mask. When the multi-axis accelerometer accelerates causing the mass to move, a corresponding movement of the mass aperture alters the illumination of the optical sensor such that the sensor signal is indicative of the acceleration.
    Type: Grant
    Filed: October 31, 2001
    Date of Patent: May 27, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: George J. Bennett
  • Patent number: 6560056
    Abstract: A disk drive is disclosed comprising a disk, a head actuated radially over the disk, a spindle motor for rotating the disk, a controller integrated circuit (IC) for generating spindle motor control data, and a motor driver IC. The motor driver IC comprises commutation circuitry for commutating the spindle motor, a status register for storing real-time status data associated with operation of the motor driver IC, and a serial interface for receiving the spindle motor control data from the controller IC and for initiating a transfer of the real-time status data to the controller IC.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: May 6, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventor: Robert P. Ryan
  • Patent number: 6552880
    Abstract: The present invention may be regarded as a disk drive with protection against damage due to a thermal asperity. The disk drive comprises a disk having a surface with an asperity, and a magneto-resistive head actuated radially over the surface of the disk for generating a read signal comprising a thermal asperity component caused by the magneto-resistive head contacting the asperity on the surface of the disk. A bias generator is provided for generating an electrical bias applied to the magneto-resistive head, and a thermal asperity detector detects the thermal asperity component in the read signal. When the thermal asperity component is detected, the electrical bias is reduced for a time interval, thereby protecting the magneto-resistive head.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: April 22, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: Gary L. Dunbar, David M. Hannon, James Weispfenning, Jodie A. Christner, Timothy Bouwkamp
  • Patent number: 6549359
    Abstract: A disk drive is disclosed comprising a disk, a head actuated radially over the disk, and a spindle motor for rotating the disk, the spindle motor comprising a plurality of windings and a rotor rotatable at a variable spin rate, wherein the rotor generates a back EMF (BEMF) voltage across the windings proportional to the spin rate of the rotor. A plurality of switching elements are coupled to the windings, and switch control logic generates switch control signals applied to the switching elements for commutating the spindle motor during normal operation and for generating an internal supply voltage from the BEMF during a spin down mode, the internal supply voltage for parking the head. A signal generator generates a periodic signal, the periodic signal for periodically grounding the windings during the spin down mode in order to boost the internal supply voltage, wherein grounding the windings applies a braking torque to the spindle motor.
    Type: Grant
    Filed: May 31, 2000
    Date of Patent: April 15, 2003
    Assignee: Western Digital Technologies, Inc.
    Inventors: George J. Bennett, Robert P. Ryan
  • Patent number: 6550021
    Abstract: An internet-implemented method of supports a component repair service. The service is rendered for a component of a computer that has an interface for communicating with a web site via the internet. While communicating via the internet, the computer operates under a first operating system that has a protection feature that precludes application-level programming from performing a function to test the component. The method comprises running a first program on the first operating system to cause a display prompt for input control to initiate a test of the component. The method comprises responding to the input control by: exiting from the first operating system and entering a second operating system; running a second program on the second operating system to perform an in situ test of the component to generate a test result; and responding to the test result to store a recorded test result.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: April 15, 2003
    Assignee: Western Digital Ventures, Inc.
    Inventors: Lawrence J. Dalphy, Thomas R. Harbert, David M. Smith