Patents Assigned to Stubinen Utreckling AB
  • 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