Patents by Inventor Douglas E. Ludwig

Douglas E. Ludwig 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: 6464493
    Abstract: A multi-axis rotary seal system to provide a gas-tight seal between a stationary hood and the end of a rotating tube kiln comprises a stationary hood positioned at the end of the rotary tube and having extended therefrom, a fully flexible bellows attached at the other end to a structural ring which, in turn, is attached to a graphite ring, slidably pressed against a flange on the rotary tube to form an atmospheric seal. The structural ring is held to the stationary hood by multi-axis supports that allow movement of the ring in three axial directions. In operation, during expansion and contraction of the rotating tube and eccentricities of motion, the integrity of the slidable seal formed by the graphite ring against the mating surface of the tube flange, is maintained by a biasing device pressing the graphite ring and the tube flange together in slidable engagement.
    Type: Grant
    Filed: August 7, 2001
    Date of Patent: October 15, 2002
    Assignee: Harper International Corp.
    Inventors: Brian A. Polino, Douglas E. Ludwig, Carl H. Vander Weide, David M. Bencic, Edgard Matrak
  • Publication number: 20020022209
    Abstract: A multi-axis rotary seal system to provide a gas-tight seal between a stationary hood and the end of a rotating tube kiln comprises a stationary hood positioned at the end of the rotary tube and having extended therefrom, a fully flexible bellows attached at the other end to a structural ring which, in turn, is attached to a graphite ring, slidably pressed against a flange on the rotary tube to form an atmospheric seal. The structural ring is held to the stationary hood by multi-axis supports that allow movement of the ring in three axial directions. In operation, during expansion and contraction of the rotating tube and eccentricities of motion, the integrity of the slidable seal formed by the graphite ring against the mating surface of the tube flange, is maintained by a biasing device pressing the graphite ring and the tube flange together in slidable engagement.
    Type: Application
    Filed: August 7, 2001
    Publication date: February 21, 2002
    Inventors: Brian A. Polino, Douglas E. Ludwig, Carl H. Vander Weide, David M. Bencic, Edgard Matrak