Patents by Inventor John W. Duke

John W. Duke 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: 4384624
    Abstract: An earth boring head comprising a generally conical earth boring member having a forward portion and a rearward portion. At least one aperture is fashioned in a forward portion of the earth boring member for liberating a lubricating fluid around the rearward portion of the conical member as the member is moved through an earth formation. In a preferred embodiment the conical earth boring member is fitted with a generally conical pilot member coaxially mounted in front of the conical earth boring member.
    Type: Grant
    Filed: February 25, 1981
    Date of Patent: May 24, 1983
    Inventors: John W. Duke, John A. Duke
  • Patent number: 4306626
    Abstract: A hydraulic earth boring machine for forming conduit passageways beneath established surfaces such as roadways, walkways, or the like. The boring machine includes a hydraulic cylinder having an open axial passageway for receiving a boring shaft. A drive cylinder surrounds the boring shaft and is driven by the hydraulic cylinder. A gripping assembly is mounted upon a trailing end of the drive cylinder and selectively couples the drive cylinder to the boring shaft. An elevating and vertical aiming assembly is mounted upon the hydraulic cylinder for facilely providing positioning of the boring machine, in situ, within an earth trench. In addition, an axial bracing and horizontal angling assembly is mounted upon the cylinder for mounting the boring machine within the trench adjacent an established surface.
    Type: Grant
    Filed: May 21, 1980
    Date of Patent: December 22, 1981
    Inventors: John W. Duke, John A. Duke