Patents by Inventor Hung T. Du

Hung T. Du 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: 9472989
    Abstract: A method of manufacturing an armature for an electric motor, includes: placing a commutator and a lamination stack on an armature shaft, winding magnet wire in slots in the lamination stacks to form coils, attaching ends of the magnet wire to the commutator, and molding plastic around the magnet wire and around the shaft of the armature at ends of the lamination stack. A spinning inertia of the armature is adjusted by adjusting at least one of a mass of the plastic molded and a distribution of the plastic molded. Alternatively and/or additionally, at least one of a resonant frequency and critical speed of the armature is adjusted by adjusting at least one of a geometry of the plastic molded, the physical properties of the plastic and the mechanical properties of the plastic.
    Type: Grant
    Filed: August 26, 2014
    Date of Patent: October 18, 2016
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Patent number: 8997332
    Abstract: A method for forming an armature for an electric motor includes: securing a lamination stack having slots therein on an armature shaft, securing a commutator on one end of the armature shaft, winding magnet wires in the slots in the lamination stack and securing ends of the magnet wires to the commutator, the magnet wires having armature lead wires that extend from the slots to the commutator; and molding plastic over the magnet wires to encase at least the armature lead wires in plastic. Alternatively and/or additionally, plastic is molded over the magnet wires to retain them in the slots and to support the armature lead wires and prevent them from vibrating when the armature rotates during operation.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: April 7, 2015
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Patent number: 8937412
    Abstract: An electric motor for a power tool includes a stator and an armature disposed in the stator. The armature includes a lamination stack having slots therein; an armature shaft extending coaxially through the lamination stack; a plurality of magnet wires wound in the slots of the lamination stack; a commutator disposed on the armature shaft to which ends of the magnet wires are electrically coupled; and thermally conductive plastic at least partially encasing the magnet wires, the thermally conductive plastic having a base polymer that is a blend of at least two polymers.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: January 20, 2015
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Publication number: 20140360008
    Abstract: A method of manufacturing an armature for an electric motor, includes: placing a commutator and a lamination stack on an armature shaft, winding magnet wire in slots in the lamination stacks to form coils, attaching ends of the magnet wire to the commutator, and molding plastic around the magnet wire and around the shaft of the armature at ends of the lamination stack. A spinning inertia of the armature is adjusted by adjusting at least one of a mass of the plastic molded and a distribution of the plastic molded. Alternatively and/or additionally, at least one of a resonant frequency and critical speed of the armature is adjusted by adjusting at least one of a geometry of the plastic molded, the physical properties of the plastic and the mechanical properties of the plastic.
    Type: Application
    Filed: August 26, 2014
    Publication date: December 11, 2014
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Patent number: 8901787
    Abstract: An electric motor has a stator in which an armature is disposed. The armature has a shaft. One of the stator or the armature includes a lamination stack having slots in which magnet wires are wound, the magnet wires having a coating of heat activated adhesive. There is further provided plastic molded around the magnet wires with heat of the plastic activating the heat activated adhesive on the magnet wires during molding of the plastic to bond the magnet wires together.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: December 2, 2014
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Patent number: 8850690
    Abstract: A method of manufacturing an armature for an electric motor, includes: placing a commutator and a lamination stack on an armature shaft, winding magnet wire in slots in the lamination stacks to form coils, attaching ends of the magnet wire to the commutator, and molding plastic around the magnet wire and around the shaft of the armature at ends of the lamination stack. A spinning inertia of the armature is adjusted by adjusting at least one of a mass of the plastic molded and a distribution of the plastic molded. Alternatively and/or additionally, at least one of a resonant frequency and critical speed of the armature is adjusted by adjusting at least one of a geometry of the plastic molded, the physical properties of the plastic and the mechanical properties of the plastic.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: October 7, 2014
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Patent number: 8823234
    Abstract: An electric motor has a rotor and a stator. The rotor or the stator has arced permanent magnets that have essentially the same inner radius (IR) and outer radius (OR). In an aspect, the stator has a stator housing having a plurality of poles. Each pole includes a plurality of flat magnets affixed to an inner surface of the stator housing. In an aspect, flats on the outside of the stator housing key the stator assembly in a power tool housing. In an aspect, flat magnets are pre-magnetized, pre-assembled with alternating magnetic polarities, inserted into a stator housing, and remagnetized to a final, desired magnetic polarity configuration. In an aspect, pre-magnetized magnets and unmagnetized magnets are pre-assembled with unmagnetized magnets between magnetized magnets, the pre-assembled magnets inserted into a stator housing, and the unmagnetized magnets magnetized to a final, desired magnetic polarity configuration.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: September 2, 2014
    Assignee: Black & Decker Inc.
    Inventors: Earl M. Ortt, Hung T. Du, Sankarshan Murthy
  • Patent number: 8657030
    Abstract: A cordless power tool (300) has a transmission (12) having multiple speed ranges In the light torque range, the speed of a motor (8) of the cordless power tool is held constant to hold an output speed of the transmission (12) constant until motor power reaches a predetermined percentage of the maximum watts out of the motor.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: February 25, 2014
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Josh West
  • Publication number: 20130342042
    Abstract: A power tool is provided including a housing and an electric motor disposed in the housing. The motor includes a stator having pole pieces mated together and field coils disposed on the pole pieces, the stator having an outside diameter. The motor also includes an armature having an outside diameter that is at least 0.625 of the outside diameter of the stator.
    Type: Application
    Filed: August 22, 2013
    Publication date: December 26, 2013
    Applicant: Black & Decker Inc.
    Inventors: Hung T. Du, Earl M. Ortt, Brandon L. Verbrugge, Garrett P. McCormick, Michael A. Zemlock, Kevin M. Hogan, Jiaqi Zhang, Ren H. Wang, Frank A. Mannarino, Spencer G. Maid, Shane Ashley Moll, James C. Benton
  • Publication number: 20130300221
    Abstract: An electric motor has a stator in which an armature is disposed. The armature has a shaft. One of the stator or the armature includes a lamination stack having slots in which magnet wires are wound, the magnet wires having a coating of heat activated adhesive. There is further provided plastic molded around the magnet wires with heat of the plastic activating the heat activated adhesive on the magnet wires during molding of the plastic to bond the magnet wires together.
    Type: Application
    Filed: November 1, 2012
    Publication date: November 14, 2013
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Publication number: 20130291371
    Abstract: A method of manufacturing an armature for an electric motor, includes: placing a commutator and a lamination stack on an armature shaft, winding magnet wire in slots in the lamination stacks to form coils, attaching ends of the magnet wire to the commutator, and molding plastic around the magnet wire and around the shaft of the armature at ends of the lamination stack. A spinning inertia of the armature is adjusted by adjusting at least one of a mass of the plastic molded and a distribution of the plastic molded. Alternatively and/or additionally, at least one of a resonant frequency and critical speed of the armature is adjusted by adjusting at least one of a geometry of the plastic molded, the physical properties of the plastic and the mechanical properties of the plastic.
    Type: Application
    Filed: November 1, 2012
    Publication date: November 7, 2013
    Inventors: Hung T. Du, Brandon L. Verbrugge, Joshua F. West, Michael R. Sell, Richard T. Walter, David J. Smith, Earl M. Ortt, John C. Stone, Howard T. White
  • Patent number: 8558420
    Abstract: A power tool has a motor having a stator made by separately forming pole pieces and field coils. The field coils are placed over necks of the pole path pieces. An armature has an outside diameter of at least 0.625 the outside diameter of the stator is placed in the stator. The housing has a girth of 200 mm or less with the motor wound to provide a maximum watts out to housing girth ratio of at least 5 maximum watts outs to 1 mm of housing girth. The field coils may be formed so that they extend beyond pole tips of the pole pieces.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: October 15, 2013
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Earl M. Ortt, Brandon L. Verbrugge, Garrett P. McCormick, Michael A. Zemlock, Kevin M. Hogan, Jiaqi Zhang, Ren Hong Wang, Frank A. Mannarino, Spencer G. Maid, Shane Ashley Moll, James C. Benton
  • Patent number: 8324764
    Abstract: An electric motor has a stator in which an armature is disposed. The armature has a lamination stack having slots in which magnet wires are wound. An armature shaft extends coaxially through the lamination stack and a commutator is disposed on the armature shaft to which ends of the magnet wires are electrically coupled. The magnet wires are at least partially encased in thermally conductive plastic. When the thermally conductive plastic is molded, a balancing feature is formed of the thermally conductive plastic. In aspects, the balancing feature can include a layer of the plastic from which plastic can be removed during balancing; one or more balancing rings adjacent axial sides of the lamination stack from which plastic can be removed to balance the armature; or one or more balancing rings having one or more pockets therein in which one or more weights are disposed to balance the armature.
    Type: Grant
    Filed: May 16, 2012
    Date of Patent: December 4, 2012
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Richard T. Walter
  • Publication number: 20120248902
    Abstract: A power tool has a motor having a stator made by separately forming pole pieces and field coils. The field coils are placed over necks of the pole path pieces. An armature has an outside diameter of at least 0.625 the outside diameter of the stator is placed in the stator. The housing has a girth of 200 mm or less with the motor wound to provide a maximum watts out to housing girth ratio of at least 5 maximum watts outs to 1 mm of housing girth. The field coils may be formed so that they extend beyond pole tips of the pole pieces.
    Type: Application
    Filed: May 22, 2012
    Publication date: October 4, 2012
    Applicant: Black & Decker Inc.
    Inventors: Hung T. Du, Earl M. Ortt, Brandon L. Verbrugge, Garrett P. McCormick, Michael A. Zemlock, Eric J. Samuelsen, Kevin M. Hogan, Jiaqi Zhang, Ren Hong Wang, Frank A. Mannarino, Allison A. Smith, Spencer G. Maid, Therese M. Rakosky, Kyle J. Wheaton, Antonios M. Nicolaidis, Shane Ashley Moll, James C. Benton, Eric L. Bernstein
  • Publication number: 20120222288
    Abstract: An electric motor has a stator in which an armature is disposed. The armature has a lamination stack having slots in which magnet wires are wound. An armature shaft extends coaxially through the lamination stack and a commutator is disposed on the armature shaft to which ends of the magnet wires are electrically coupled. The magnet wires are at least partially encased in thermally conductive plastic. When the thermally conductive plastic is molded, a balancing feature is formed of the thermally conductive plastic. In aspects, the balancing feature can include a layer of the plastic from which plastic can be removed during balancing; one or more balancing rings adjacent axial sides of the lamination stack from which plastic can be removed to balance the armature; or one or more balancing rings having one or more pockets therein in which one or more weights are disposed to balance the armature.
    Type: Application
    Filed: May 16, 2012
    Publication date: September 6, 2012
    Applicant: BLACK & DECKER INC.
    Inventors: Hung T. Du, Richard T. Walter
  • Patent number: 8207647
    Abstract: A power tool has a motor having a stator made by separately forming pole pieces, return path pieces and field coils. The field coils are placed over necks of the pole path pieces and the return path pieces are affixed to the pole pieces. An armature having an outside diameter of at least 0.625 the outside diameter of the stator is placed in the stator. The field coils may be formed so that they extend beyond pole tips of the pole pieces.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: June 26, 2012
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Earl M. Ortt, Brandon L. Verbrugge, Garrett P. Mccormick, Michael A. Zemlock, Eric J. Samuelsen, Kevin M. Hogan, Jiaqi Zhang, Ren H. Wang, Frank A. Mannarino, Allison A. Smith, Therese M. Rakosky, Kyle J. Wheaton, Antonios M. Nicolaidis, Shane Ashley Moll, Eric L. Bernstein
  • Patent number: 8203239
    Abstract: An electric motor has a stator in which an armature is disposed. The armature has a lamination stack having slots in which magnet wires are wound. An armature shaft extends coaxially through the lamination stack and a commutator is disposed on the armature shaft to which ends of the magnet wires are electrically coupled. The magnet wires are at least partially encased in thermally conductive plastic. When the thermally conductive plastic is molded, a balancing feature is formed of the thermally conductive plastic. In aspects, the balancing feature can include a layer of the plastic from which plastic can be removed during balancing; one or more balancing rings adjacent axial sides of the lamination stack from which plastic can be removed to balance the armature; or one or more balancing rings having one or more pockets therein in which one or more weights are disposed to balance the armature.
    Type: Grant
    Filed: September 30, 2010
    Date of Patent: June 19, 2012
    Assignee: Black & Decker Inc.
    Inventors: Hung T. Du, Richard T. Walter
  • Publication number: 20110298313
    Abstract: A permanent magnet electric motor has a stator and a rotor. The stator has a stator housing with at least a North pole and a South pole, each pole including permanent magnets affixed to an inner surface of the stator housing, where at least two of the magnets within a pole have dissimilar characteristics, e.g., different widths or different grades of demagnetization resistance.
    Type: Application
    Filed: May 20, 2011
    Publication date: December 8, 2011
    Applicant: Black & Decker Inc.
    Inventors: Stephen Osborne, Colin Crosby, Sankarshan Murthy, Hung T. Du, Earl M. Ortt
  • Publication number: 20110278966
    Abstract: A permanent magnet electric motor has a stator and a rotor. The stator has a stator housing with at least a North pole and a South pole. Each pole includes at least two permanent magnets arranged on an inner surface of the stator housing near the pole tips and an overmold of magnetic material molded around the permanent magnets and over the inner surface of the stator between the permanent magnets. Alternatively, an overmold of magnetic material may be provided over an inner surface of the stator, where the thickness of the overmold layer is greater near tips of each pole than in the middle portion of each pole.
    Type: Application
    Filed: May 20, 2011
    Publication date: November 17, 2011
    Applicant: Black & Decker Inc.
    Inventors: Stephen Osborne, Colin Crosby, Sankarshan Murthy, Hung T. Du, Earl M. Ortt
  • Patent number: 8022654
    Abstract: A power tool has an electric motor with field windings. Each field winding includes two coils. When the motor is first energized, the two coils of each field winding are connected in series, reducing in-rush current. Upon expiration of a soft start period, the two coils of each field winding are connected in parallel. In another aspect, the field windings that are connected in series with a separate start winding when the motor is first energized. Upon expiration of the soft start period, the start winding is bypassed. In another aspect, the field windings are connected in series with a start impedance when the motor is first energized and a time delay relay having a set of delay contacts coupled across the start impedance energized. Upon expiration of the soft start period, the time delay contacts close, bypassing the start impedance. In an aspect, the motor is a universal motor.
    Type: Grant
    Filed: July 10, 2006
    Date of Patent: September 20, 2011
    Assignee: Black & Decker Inc.
    Inventors: Peter Zhao, Hung T. Du, Garrett P. McCormick