Patents by Inventor Donald E. Ritze

Donald E. Ritze 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).

  • Roof maintenance stair step apparatus
    Patent number: 5664641
    Abstract: A stair step assembly provides a safe means for mounting a peaked roof. Individual steps interlock with each other and with tiles of a tile roof so that the assembly cannot slide off the roof. Each step has a platform supported from below by a frame having a primary and secondary rest. The rests lie in contact with the roof and provide a foot constructed so that one portion of the foot is in contact with an vertical edge of a line of tiles to prevent the step from sliding.
    Type: Grant
    Filed: March 6, 1996
    Date of Patent: September 9, 1997
    Inventor: Donald E. Ritze