Patents by Inventor Franz D. Hahn

Franz D. Hahn 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).

  • Device for shutting off a pipe
    Patent number: 4660805
    Abstract: The invention relates to a device for shutting off a pipe using generally U-shaped spring steel strips as sealing elements, each such element comprising a pair of arms which converge toward one another form an arcuate web at an acute angle. The deformation of the two flat arms of these sealing elements is limited by two flat, rigid rolling surfaces which are tangential to the web. Such a construction is distinguished by satisfactory functioning and a long working life.
    Type: Grant
    Filed: July 18, 1985
    Date of Patent: April 28, 1987
    Assignee: Krupp Polysius AG
    Inventors: Franz D. Hahn, Otto Heinemann, Heinz-Herbert Schmits