Patents by Inventor John Charles Dunfield

John Charles Dunfield 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: 6538836
    Abstract: An actuator arm assembly is provided in a disc drive. The disc drive includes a disc with a surface for storing information and a first actuator for moving the actuator arm assembly relative to the surface of the disc. The actuator arm assembly includes an actuator arm coupled to the first actuator, a load beam coupled to the actuator arm, a suspension coupled to the load beam and an air bearing coupled to the suspension. A transducer is mounted on the air bearing and positioned to access the surface of the disc. A second actuator is coupled to the air bearing and the load beam and is controllable to move the air bearing relative to the surface of the disc and relative to the load beam.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: March 25, 2003
    Assignee: Seagate Technology LLC
    Inventors: John Charles Dunfield, Gunter Karl Heine
  • Patent number: 6335850
    Abstract: An actuator arm assembly is provided in a disc drive. The disc drive includes a disc with a surface for storing information and a first actuator for moving the actuator arm assembly relative to the surface of the disc. The actuator arm assembly includes an actuator arm coupled to the first actuator, a load beam coupled to the actuator arm, a suspension coupled to the load beam and an air bearing coupled to the suspension. A transducer is mounted on the air bearing and positioned to access the surface of the disc. A second actuator is coupled to the air bearing and the load beam and is controllable to move the air bearing relative to the surface of the disc and relative to the load beam.
    Type: Grant
    Filed: February 4, 2000
    Date of Patent: January 1, 2002
    Assignee: Seagate Technology, Inc.
    Inventors: John Charles Dunfield, Gunter Karl Heine
  • Patent number: 6029978
    Abstract: A motor is disclosed which includes a shaft and a hub rotating relative to one another and defining a bore therebetween. Also disclosed is a magnetic fluid seal which includes pole pieces supported from the hub, the pole pieces extend toward the shaft. The pole pieces sandwich a non-conducting magnet in a space between the pole pieces. In addition, a contacting process is supported from one of the pole pieces for making electrical contact with the other pole piece to enhance electrical conductivity between the hub and shaft.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: February 29, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Robert Michael Pelstring, John Charles Dunfield
  • Patent number: 5956204
    Abstract: A magnetic disc drive system includes a hydrodynamic bearing. The magnetic disc drive system includes a disc drive chassis, a magnetic storage disc, and a read/write transducer adjacent to the disc for reading and writing information on the disc. The hydrodynamic bearing assembly rotatably couples the magnetic storage disc to the disc drive chassis. The hydrodynamic bearing assembly includes a fluid path therethrough for circulating a fluid. A permanent magnet is placed in the fluid path and used for attracting magnetic particles carried in the fluid.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: September 21, 1999
    Assignee: Seagate Technology, Inc.
    Inventors: John Charles Dunfield, Norbert Steven Parsoneault
  • Patent number: 5949613
    Abstract: A spindle motor assembly adapted for rotationally supporting a load about a base includes a rotor rotatably mounted on the base with its outer periphery capable of supporting a load, a stator and a plurality of magnets mounted on the outer periphery of the rotor. The stator includes a plurality of stator laminations with selective portions of the stator laminations forming stator cores. A plurality of magnets are mounted on the outer periphery of the rotor in an operating relationship with the stator cores. A plurality of conductors are wound on the stator cores. The stator includes a resilient covering located around the plurality of laminations and further having a routing means to route the conductors between the stator cores, an attaching means to attach the stator to the base and a connecting means. The connecting means includes a first connector block with a plurality of first conductor pads, with a first end and a second end. Ends of the conductors are connected to the first end of the conductor pads.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: September 7, 1999
    Assignee: Seagate Technology, Inc.
    Inventors: Michael Bruce Moir, Richard Gene Krum, John Charles Dunfield, Gregory James Blanchette
  • Patent number: 5907455
    Abstract: The spindle motor is integrated with the disc by incorporating one of the poles or coils of the motor with a region on the disc, and the remaining portion of the motor being distributed over an internal surface or surfaces of the housing for the disc, or over the edge of an adjacent disc. By activating the portion of the motor which is supported from the disc housing, the disc can be rotationally driven. The motor poles may be either deposited or etched on the disc, or separately formed and attached to the disc housing. The result is a substantially smaller height disc drive, achieved with a much reduced cost.
    Type: Grant
    Filed: May 15, 1996
    Date of Patent: May 25, 1999
    Assignee: Seagate Technology, Inc.
    Inventor: John Charles Dunfield
  • Patent number: 5815345
    Abstract: Spindle motor electrical- and motor-to-base interfaces. A compliant connector along with a circuit on a support flange is provided below a stator assembly for providing: An insertable spindle motor to drive base with less specific orientation. The support flange may comprise a small printed circuit cable or a printed circuit board. Additionally, non-specific orientation of a spindle motor to drive base assembly is described using circular traces oriented about a support flange. A circular connector is also described, as a biased support flange.
    Type: Grant
    Filed: July 30, 1996
    Date of Patent: September 29, 1998
    Assignee: Seagate Technology, Inc.
    Inventors: Robert Michael Pelstring, Klaus Dieter Kloeppel, John Charles Dunfield, Michael Kenneth Andrews, Clifford Thomas Jue
  • Patent number: 5808839
    Abstract: A disc drive cartridge is disclosed comprising a central actuator arm pivot hub mounting one magnetic pole, which in turn rotates within and overlaps a u-shaped upright base and sleeve supporting a second non-aligned magnetic pole. The system relies on the radial repulsive forces of the separate magnetic poles to achieve significant radial stability; in certain embodiments, attractive forces between axially aligned magnetic poles or a magnetic pole and a sleeve of high permeability magnetic material are also utilized to enhance the axial stability of the system. The rotating hub supports on one side one or more actuator arms and on the other side a coil of a voice coil motor, so that this magnetic bearing can be the central pivot for a very small compact and low noise disc drive cartridge.
    Type: Grant
    Filed: September 16, 1996
    Date of Patent: September 15, 1998
    Assignee: Seagate Technology, Inc.
    Inventors: John Charles Dunfield, Kamran Oveyssi
  • Patent number: 5774974
    Abstract: A disc drive includes a disc drive motor for rotating a storage disc. The motor includes a motor base which carries a wiring assembly having a plurality of electrical contacts. A rotor hub is rotatably coupled to the base and rotatably carries a storage disc. The rotor hub includes a permanent magnet. A stator assembly includes a plurality of stator windings adapted for operation with the permanent magnet of the rotor hub. A wire guide coupled to the stator assembly positions wires of the stator windings adjacent the electrical contacts of the wiring assembly. The wires are soldered to the contacts after which the wiring guide can be removed. The stator assembly can be "potted" in an adhesive to reduce problems associated with resonant frequency of the disc drive motor. The wire guide acts as a retainer for the adhesive preventing the adhesive from interfering with rotation of the rotatable hub.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: July 7, 1998
    Assignee: Seagate Technology, Inc.
    Inventors: John Charles Dunfield, Steven Craig Knoche, Klaus Dieter Kloeppel
  • Patent number: 5694268
    Abstract: A disc drive spindle motor for rotating at least one disc in a data storage device includes a base, a shaft, a rotor and a stator. A bearing interconnects the rotor with the shaft and allows the rotor to rotate about the shaft. An overmold encapsulates at least a portion of the stator and provides the stator with a smooth external surface. The overmold mechanically isolates the stator from the base and damps sympathetic vibrations in the stator structure to reduce the generation of acoustic noise in the storage device.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: December 2, 1997
    Assignee: Seagate Technology, Inc.
    Inventors: John Charles Dunfield, Gunter Karl Heine