Patents by Inventor Birger Johannes Laing

Birger Johannes Laing 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).

  • Temperature regulated hot water recirculation system
    Patent number: 6227235
    Abstract: In a hot and cold water distribution system, cooled down water in the hot water distribution line is automatically drained toward the cold water distribution line by a connection system consisting essentially of a centrifugal pump in series with a valve oriented to prevent the flow of cold water into the hot water distribution line or of hot water into the cold water distribution line by the same valve.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: May 8, 2001
    Inventors: Johannes Nikolaus Laing, Birger Johannes Laing