Patents by Inventor Carl Helwig

Carl Helwig 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: 3941034
    Abstract: A filtering attachment for the air intake of an automobile passenger compartment. A large rectangular sheet of laminated foil, vinyl and paper has a central opening over which is mounted a filter unit. The filter unit comprises two layers of non-woven paper heat sealed together to form a plurality of adjacent pockets, each of which contains pieces of activated charcoal. A fine mesh screen is mounted in overlying relationship to the filter unit. The attachment is mounted in overlying relationship to the air intake of the automobile so that all air entering the passenger compartment passes through the filter unit.
    Type: Grant
    Filed: July 11, 1974
    Date of Patent: March 2, 1976
    Inventors: Carl Helwig, Dolores F. Helwig