Patents by Inventor Roger B. Tisdale

Roger B. Tisdale 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).

  • Puzzle bolt
    Patent number: 5147093
    Abstract: A puzzle is disclosed which includes an elongated left-hand threaded bolt carrying a split lock washer and having a nut at one end. The other end of the bolt is partially threaded into a second nut which has a short length of another bolt threaded at its end. The object of the puzzle is to figure out how to remove the lock washer from the bolt.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: September 15, 1992
    Inventor: Roger B. Tisdale