Patents by Inventor Martha O. Bertman

Martha O. Bertman 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).

  • Modular computer teaching device
    Patent number: 3994076
    Abstract: A cube is provided with four side walls, and an open bottom and top. Mounted within the cube is a flip-flop unit made up of three wings, one wing being longer than the other two so that when a marble is dropped in the cube, the flip-flop unit will rotate until the longer wing is in contact with one of the side walls. A plurality of each such cubes are provided in order to teach adding and subtracting in the binary system and to perform many other functions.
    Type: Grant
    Filed: September 30, 1975
    Date of Patent: November 30, 1976
    Inventor: Martha O. Bertman