Patents by Inventor Knut Hobrecht

Knut Hobrecht 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: 5958255
    Abstract: A filtering method and apparatus for continuously filtering a polymeric melt, which includes a plurality of filter chambers which are arranged in a melt flow path parallel to one another. Also, an intermediate filter is arranged parallel to the filter chambers. When one of the filter chambers is disconnected for the purpose of cleaning or replacing the filter element therein, the intermediate filter is connected synchronously in the melt flow path and, after the filter chamber is cleaned, or the filter element is exchanged, the flow is switched back through the filter chamber, and the intermediate filter is again disconnected.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: September 28, 1999
    Assignee: Barmag AG
    Inventors: Knut Hobrecht, Friedhelm Itter
  • Patent number: 5928523
    Abstract: A filtering method and apparatus for continuously filtering a polymeric melt, which includes a plurality of filter chambers which are arranged in a melt flow path parallel to one another. Also, an intermediate filter is arranged parallel to the filter chambers. When one of the filter chambers is disconnected for the purpose of cleaning or replacing the filter element therein, the intermediate filter is connected synchronously in the melt flow path and, after the filter chamber is cleaned, or the filter element is exchanged, the flow is switched back through the filter chamber, and the intermediate filter is again disconnected.
    Type: Grant
    Filed: September 17, 1996
    Date of Patent: July 27, 1999
    Assignee: Barmag AG
    Inventors: Knut Hobrecht, Friedhelm Itter
  • Patent number: 5607585
    Abstract: An apparatus for filtering plastic melts, which comprises a filter housing (1) having at least one cylindrical filter receiving chamber (8), and with a tubular filter cartridge (2) mounted in the chamber. An annular melt flow space (9) for the plastic melt is defined between the outer periphery of the filter and the inside wall of the chamber, such that the melt flows radially inwardly through the filter medium of the filter cartridge and into the central passage of the filter cartridge and then to an outlet opening of the housing. An additional melt flow outlet channel (12) is positioned adjacent the downstream end of the filter cartridge, and in one embodiment, the melt is able to flow via the additional melt flow outflow channel to the outside of the housing. In a second embodiment, the melt can flow via the additional melt flow outflow channel and an additional filter (11) and return to the main flow.
    Type: Grant
    Filed: July 17, 1995
    Date of Patent: March 4, 1997
    Assignee: Barmag AG
    Inventors: Knut Hobrecht, Jorg Alexander