Patents by Inventor Alfred D. Duncan

Alfred D. Duncan 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: D245397
    Type: Grant
    Filed: March 8, 1976
    Date of Patent: August 16, 1977
    Inventor: Alfred D. Duncan
  • Patent number: D246736
    Type: Grant
    Filed: November 26, 1975
    Date of Patent: December 20, 1977
    Inventors: Bernard R. Barrett, Alfred D. Duncan
  • Patent number: D246737
    Type: Grant
    Filed: November 26, 1975
    Date of Patent: December 20, 1977
    Inventors: Bernard R. Barrett, Alfred D. Duncan