Patents by Inventor David G. Duckworth

David G. Duckworth 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: 9725967
    Abstract: A centralizer for centralizing a pipe downhole in a well is provided. The centralizer includes a plurality of arcuate cuffs having first and second ends. The cuffs are affixed adjacent to the pipe's exterior wall, and positioned circumferentially adjacent around the pipe. The cuffs are flexible so as to be positioned in a first condition wherein the cuffs are retracted radially inward so as to be substantially flat against the pipe's exterior wall. The centralizer includes a lock for maintaining the cuffs substantially flat against the pipe's exterior wall until the centralizer has been transported downhole. Further, the centralizer includes an actuator for unlocking the lock so as to allow the cuffs to expand radially outward to form a loop wherein the loop has a central axis parallel to pipe's longitudinal axis. Preferably, the centralizer includes a collar causing the cuffs to all expand or retract together.
    Type: Grant
    Filed: July 23, 2014
    Date of Patent: August 8, 2017
    Assignee: BP CORPORATION NORTH AMERICA INC.
    Inventors: Scott E. Jewett, David G. Duckworth
  • Patent number: 9626091
    Abstract: A centralizer for centralizing a pipe downhole in a well is provided. The centralizer includes a plurality of arcuate cuffs having first and second ends. The cuffs are affixed adjacent to the pipe's exterior wall, and positioned circumferentially adjacent around the pipe. The cuffs are flexible so as to be positioned in a first condition wherein the cuffs are retracted radially inward so as to be substantially flat against the pipe's exterior wall. The centralizer includes a lock for maintaining the cuffs substantially flat against the pipe's exterior wall until the centralizer has been transported downhole. Further, the centralizer includes an actuator for unlocking the lock so as to allow the cuffs to expand radially outward to form a loop wherein the loop has a central axis parallel to pipe's longitudinal axis. Preferably, the centralizer includes a collar causing the cuffs to all expand or retract together.
    Type: Grant
    Filed: December 7, 2015
    Date of Patent: April 18, 2017
    Assignee: BP CORPORATION NORTH AMERICA INC.
    Inventors: Scott E. Jewett, David G. Duckworth
  • Publication number: 20160084021
    Abstract: A centralizer for centralizing a pipe downhole in a well is provided. The centralizer includes a plurality of arcuate cuffs having first and second ends. The cuffs are affixed adjacent to the pipe's exterior wall, and positioned circumferentially adjacent around the pipe. The cuffs are flexible so as to be positioned in a first condition wherein the cuffs are retracted radially inward so as to be substantially flat against the pipe's exterior wall. The centralizer includes a lock for maintaining the cuffs substantially flat against the pipe's exterior wall until the centralizer has been transported downhole. Further, the centralizer includes an actuator for unlocking the lock so as to allow the cuffs to expand radially outward to form a loop wherein the loop has a central axis parallel to pipe's longitudinal axis. Preferably, the centralizer includes a collar causing the cuffs to all expand or retract together.
    Type: Application
    Filed: December 7, 2015
    Publication date: March 24, 2016
    Applicant: BP Corporation North America Inc.
    Inventors: Scott E. Jewett, David G. Duckworth
  • Publication number: 20150027684
    Abstract: A centralizer for centralizing a pipe downhole in a well is provided. The centralizer includes a plurality of arcuate cuffs having first and second ends. The cuffs are affixed adjacent to the pipe's exterior wall, and positioned circumferentially adjacent around the pipe. The cuffs are flexible so as to be positioned in a first condition wherein the cuffs are retracted radially inward so as to be substantially flat against the pipe's exterior wall. The centralizer includes a lock for maintaining the cuffs substantially flat against the pipe's exterior wall until the centralizer has been transported downhole. Further, the centralizer includes an actuator for unlocking the lock so as to allow the cuffs to expand radially outward to form a loop wherein the loop has a central axis parallel to pipe's longitudinal axis. Preferably, the centralizer includes a collar causing the cuffs to all expand or retract together.
    Type: Application
    Filed: July 23, 2014
    Publication date: January 29, 2015
    Inventors: SCOTT E. JEWETT, DAVID G. DUCKWORTH
  • Patent number: 8890720
    Abstract: A light guide is provided for illuminating innumerable constructions, but which is ideally suited for illuminating the keys of a keyboard. The light guide includes a translucent planar plate having a top, a bottom and sides. Further, the light guide includes one or more cavities which project upwardly into the translucent plate from its bottom surface. The cavities are hollow or filled with a translucent material so that the translucent plate and the one or more cavities form translucent interfaces where the cavities interface with the plate. The light guide also includes a reflector which covers the plate bottom and cavity openings.
    Type: Grant
    Filed: January 12, 2012
    Date of Patent: November 18, 2014
    Inventors: Michael Shipman, David G. Duckworth
  • Patent number: 8690368
    Abstract: A light guide is provided for illuminating innumerable constructions, but which is ideally suited for illuminating the keys of a keyboard. The light guide includes a translucent planar plate having a top, a bottom and sides. Further, the light guide includes one or more cavities which project upwardly into the translucent plate from its bottom surface. The cavities are hollow or filled with a translucent material so that the translucent plate and the one or more cavities form translucent interfaces where the cavities interface with the plate. The light guide also includes a reflector which covers the plate bottom and cavity openings. Light produced by a light source, preferably in the form of one or more LEDs, is transmitted to and through the translucent plate until striking the plate-cavity interfaces where the light is refracted into the cavities' interior or reflected upwardly to the plate's upper surface.
    Type: Grant
    Filed: August 22, 2005
    Date of Patent: April 8, 2014
    Inventors: Michael Shipman, David G. Duckworth
  • Publication number: 20120139843
    Abstract: A light guide is provided for illuminating innumerable constructions, but which is ideally suited for illuminating the keys of a keyboard. The light guide includes a translucent planar plate having a top, a bottom and sides. Further, the light guide includes one or more cavities which project upwardly into the translucent plate from its bottom surface. The cavities are hollow or filled with a translucent material so that the translucent plate and the one or more cavities form translucent interfaces where the cavities interface with the plate. The light guide also includes a reflector which covers the plate bottom and cavity openings.
    Type: Application
    Filed: January 12, 2012
    Publication date: June 7, 2012
    Inventors: Michael Shipman, David G. Duckworth
  • Publication number: 20090201179
    Abstract: A keyboard is provided having illuminating keys. A preferred keyboard includes scissor actuators for guiding and stabilizing each key in its upward and downward movement. A substantially translucent elastomeric diaphragm including elastomeric domes underlies the keys for biasing the keys upwardly. A seat underlies the elastomeric domes for supporting and engaging the bottom extremities of the scissor actuators. The seat may be made of translucent plastic, which functions as a translucent upper clamshell member, or non-translucent metal having sufficiently large holes for the passage of light. A substantially translucent circuit board is positioned under the seat for the creation and transmission of signals indicating depression of key members. The seat includes central holes allowing for the depression of keys to force the elastomeric domes to engage the circuit board to create electronic signals.
    Type: Application
    Filed: April 13, 2009
    Publication date: August 13, 2009
    Inventors: Michael Shipman, David G. Duckworth
  • Patent number: 7172303
    Abstract: A keyboard is provided having illuminating keys. The keyboard includes a light channeling membrane and key members constructed at least partially of translucent material so that light produced from a light source is channeled upwardly to the upper surfaces of the key members. The light source may include LED or LEC systems in adjoining relationship to the light channeling membrane or light pipe. In a preferred embodiment, the light source is constructed of a substantially planar illuminescent sheet which underlies the light channeling membrane. In an alternative preferred embodiment, a light pipe is constructed to illuminate light laterally along a portion of its length to illuminate a plurality of key members.
    Type: Grant
    Filed: November 5, 2004
    Date of Patent: February 6, 2007
    Inventors: Michael Shipman, David G. Duckworth
  • Patent number: 7174127
    Abstract: A hybrid satellite communications system provides communications, particularly Internet access, to computer users. The hybrid satellite communications system includes a satellite system and a terrestrial communications system. The satellite system includes two transceivers. The first transceiver receives and transmits a first set of signals received from the terrestrial communications system to a plurality of user units. In reverse fashion, the satellite systems second transceiver receives a second set of signals in a second frequency band from the user units and transmits those signals back to the terrestrial communications system. The first set of signals (downlink signals) are of much higher frequency than the second set of signals (uplink signals). Preferably, the first set of signals are relayed by a Direct Broadcast System (DBS) satellite in a frequency band between 12.2 GHz and 12.9 GHz, while the second set of signals are relayed by a Mobile Satellite System (MSS) satellite operating between 1.
    Type: Grant
    Filed: September 17, 2002
    Date of Patent: February 6, 2007
    Assignee: ATC Technologies, LLC
    Inventors: David D. Otten, David G. Duckworth
  • Patent number: 6619523
    Abstract: An improved backpack is provided including a frame, pack shell, shoulder straps and waist strap. Connecting the pack shell to the frame of the backpack are one or more vibration dampers. Preferably, the vibration damper includes a cylindrical housing formed with a vertically extending bore aligned with the housing's central axis. A bore is configured for telescopic receipt of the siderails of the backpack frame. Located within the bore of the vibration damper is a spring which attenuates movement between the vibration damper's housing and a collar which radially projects from a portion of the frame's siderails. Preferably, the vibration damper includes an adjustable air valve for selectively controlling air to enter into and out of the chamber formed within the center of the vibration damper.
    Type: Grant
    Filed: March 20, 2002
    Date of Patent: September 16, 2003
    Inventor: David G. Duckworth
  • Publication number: 20030022625
    Abstract: A hybrid satellite communications system provides communications, particularly Internet access, to computer users. The hybrid satellite communications system includes a satellite system and a terrestrial communications system. The satellite system includes two transceivers. The first transceiver receives and transmits a first set of signals received from the terrestrial communications system to a plurality of user units. In reverse fashion, the satellite systems second transceiver receives a second set of signals in a second frequency band from the user units and transmits those signals back to the terrestrial communications system. The first set of signals (downlink signals) are of much higher frequency than the second set of signals (uplink signals). Preferably, the first set of signals are relayed by a Direct Broadcast System (DBS) satellite in a frequency band between 12.2 GHz and 12.9 GHz, while the second set of signals are relayed by a Mobile Satellite System (MSS) satellite operating between 1.
    Type: Application
    Filed: September 17, 2002
    Publication date: January 30, 2003
    Inventors: David D. Otten, David G. Duckworth
  • Patent number: D661912
    Type: Grant
    Filed: August 11, 2011
    Date of Patent: June 19, 2012
    Inventors: Donna Hulina, David G. Duckworth