Patents by Inventor Franz Lengsfeld

Franz Lengsfeld 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: 4296776
    Abstract: A gate valve includes a water cooled valve casing coaxially attachable to a conduit and a valve plate mounted in the valve casing for sliding movement relative thereto between open and closed positions of the conduit. The valve casing includes a pair of annular mounting flanges adapted to be connected to the conduit and a pair of annular U-shaped sealing rings. Each sealing ring is positioned radially inwardly of a respective mounting flange, and the sealing rings are positioned on opposite axial sides of the valve plate. Each sealing ring includes a web portion, an inner leg portion extending generally radially outwardly from the web portion and forming a sealing surface for the valve plate, and an outer leg extending generally radially outwardly from the web portion. Each outer leg is connected to a respective mounting flange. The valve casing defines therein an enclosed interior space through which cooling water is adapted to flow.
    Type: Grant
    Filed: February 22, 1980
    Date of Patent: October 27, 1981
    Assignee: Hermann Rappold & Co. GmbH
    Inventors: Rudolf Muller, Franz Lengsfeld, Johannes Uerlichs