Patents by Inventor William B. Darwin

William B. Darwin 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).

  • Hydroponic system convertible to an open or closed system
    Patent number: 4021964
    Abstract: A new and improved hydroponic system including a plant supporting chamber having an inert, supportive medium therein; a collection reservoir positioned below the plant supporting chamber; a pump reservoir for containing a nutrient solution and delivering the nutrient solution to the plant supporting chamber and first and second valve means for operating the hydroponic system as either a closed or an open hydroponic system as desired.
    Type: Grant
    Filed: February 11, 1976
    Date of Patent: May 10, 1977
    Assignee: William B. Darwin
    Inventors: William B. Darwin, Joseph Michael Livengood
  • Greenhouse
    Patent number: D252587
    Type: Grant
    Filed: October 17, 1977
    Date of Patent: August 7, 1979
    Assignee: Plant Site, Inc.
    Inventor: William B. Darwin