Patents by Inventor David P. Hillstead

David P. Hillstead 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: 4440379
    Abstract: In accordance with the present invention, an unloading assembly for a top operated lading valve is disclosed. The unloading assembly includes means for connecting an unloading outlet chamber to the existing depending valve outlet chamber of the lading valve. The unloading outlet chamber is hollow and is in fluid communication with the lading valve outlet chamber. The unloading assembly includes an operating shaft extending upwardly through the unloading outlet chamber and through the valve outlet chamber. The operating shaft includes a non-round connection portion adapted to engage a non-round connection portion of the top operating rod.
    Type: Grant
    Filed: April 16, 1982
    Date of Patent: April 3, 1984
    Assignee: ACF Industries, Incorporated
    Inventors: Gunter R. Behle, David P. Hillstead
  • Patent number: 4270729
    Abstract: A top operated tank car valve assembly includes a rod extending downwardly from the top of the tank and is attached to the valve stem of a lading valve located in the bottom of the tank. The stem engages a threaded valve sleeve provided with a mounting flange which engages a cooperating mounting flange on a valve cage. Fasteners engage the upper surface of the sleeve, and extend through the valve cage and engage threaded openings in a tank car bottom outlet mounting flange. The cage includes a valve seat for a valve closure. The valve seat is formed on the lower, internal surface of the valve cage, and circumferentially spaced openings are formed in the valve cage for lading flow. Laterally spaced projections extend upwardly from the lading valve closure. A valve stem retainer includes a pair of formed retainer members which define a cavity or opening.
    Type: Grant
    Filed: December 13, 1978
    Date of Patent: June 2, 1981
    Assignee: ACF Industries, Incorporated
    Inventors: Gunter R. Behle, David P. Hillstead
  • Patent number: 4265182
    Abstract: In a railway car truck a lower transom extends between transversely spaced side frames. The side frames include depressed portions having transversely aligned vertical openings or slots which receive spring groups. A bolster including a center connection extends between the side frames above the transom and rests on the spring groups. The side frames each include a hollow post extending upwardly between the spring groups. The bolster includes a depending post which surrounds the side frame post. A friction damping assembly including upper and lower wedges is located within the side frame post and the bolster post. The upper and lower wedges include rear wear plates which engage the side frame post. The upper and lower wedges include an opening to receive a spring extending upwardly from the side frame depressed portion. The lower wedge has at least one inclined surface which slidingly engages at least one inclined surface on the upper wedge.
    Type: Grant
    Filed: July 2, 1979
    Date of Patent: May 5, 1981
    Assignee: ACF Industries, Inc.
    Inventors: Robert K. Neff, David P. Hillstead
  • Patent number: 4198032
    Abstract: In accordance with the present invention a tank car mounting flange is welded to an opening in the tank bottom and preferably does not extend below the bottom surface of the tank more than one (1) inch to comply with AAR and DOT Regulations. A valve body including a valve seat is located concentrically within the mounting flange and is removably attached to the mounting flange. The valve body may be attached to the mounting flange with a threaded fitting, or with fasteners and a retaining ring located within the mounting flange, in which fasteners holding the retaining ring in place extend into the mounting flange. A depending housing including a lower operator is attached to the mounting flange or to the retaining ring with fasteners which define a shear plane.
    Type: Grant
    Filed: February 21, 1978
    Date of Patent: April 15, 1980
    Assignee: ACF Industries, Incorporated
    Inventors: David P. Hillstead, Robert W. Randolph, Gunter R. Behle