Patents by Inventor Duane R. Chittenden

Duane R. Chittenden 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).

  • Escape mechanism for sliding block puzzles
    Patent number: 4836548
    Abstract: A mechanism for easy removal of the sliding blocks from a sliding block puzzle of tongue and groove design, allowing the user to remove and rearrange the blocks to start over.
    Type: Grant
    Filed: August 21, 1987
    Date of Patent: June 6, 1989
    Inventor: Duane R. Chittenden