Patents by Inventor Leonard J. Olson

Leonard J. Olson 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).

  • Self-cleaning non-return drainage valve
    Patent number: 4059127
    Abstract: A non-return drainage valve adapted for use with a container for drainage of fluids from the container through the valve and for prevention of the passage of liquid into the container, the valve including a buoyant plug member and probe means movable with the plug member for clearing debris from the valve.
    Type: Grant
    Filed: February 27, 1976
    Date of Patent: November 22, 1977
    Inventor: Leonard J. Olson