Patents by Inventor Walter Doubrawa

Walter Doubrawa 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).

  • Transportable apparatus for producing drinking water
    Patent number: 5059317
    Abstract: An installation for filtering drinking water out of contaminated water, which can be used in many different situations, as it consists of a hydrocyclone, a micro filter unit, a unit for reverse osmosis, a mixed bed ion exchange, a re-salting unit, a unit for ozonization, an activated carbon filter and a unit for chlorinization.
    Type: Grant
    Filed: October 2, 1989
    Date of Patent: October 22, 1991
    Inventors: Dietrich Marius, Erich Mueller, Christian Atzmueller, Walter Doubrawa, Helmut Irauscheck, Werner Meierhofer