Patents by Inventor Theo Rydman

Theo Rydman 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: 4917532
    Abstract: A grid plate includes a top side having a non-slip surface having openings to permit the growth of grass. At two sides which are arranged at an angle with respect to one another, the grid plate is provided with step-shaped lateral side walls. An abutment is molded into the vertical stepped wall, this abutment being formed by wall apertures placed into the step-shaped lateral side wall. A horizontal stepped side is used for supporting the side edges which project beyond the ribbing of the bottom side. At the lateral edge, plug-in connections are molded on, which, in the manner of hinges, lock into the wall apertures of an adjacent grid plate. The lateral edge has hooks which point downward and which, during the hinge movement, when the grid plates are emplaced, engage behind the wall of the wall apertures.
    Type: Grant
    Filed: November 15, 1988
    Date of Patent: April 17, 1990
    Assignee: Dr. Spiess Kunstoff-Recycling GmbH Co.
    Inventors: Karl Haberhauer, Wolfgang Schibalski, Walter Burcky, Theo Rydman