Patents by Inventor Gillis Franzen

Gillis Franzen 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 cleaning liquids in sand filters
    Patent number: 4655908
    Abstract: The present invention relates to a device for cleaning of liquids in sand filters of the up-stream type.
    Type: Grant
    Filed: September 11, 1985
    Date of Patent: April 7, 1987
    Assignee: Stubinen Utreckling AB
    Inventor: Gillis Franzen