Patents by Inventor Jan R. Sytstra

Jan R. Sytstra 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: 5062227
    Abstract: The invention relates to a device for breaking objects such as concrete or similar material, which device is provided with a pair of jaws having teeth which are pivotable relative to each other about a pivot pin. The device is designed to be coupled to the end of the arm of an excavator or the like by use of a hinge pin. A strut is provided between a first jaw and the arm of the excavator, while a setting cylinder coupled to the arm of the excavator with one end is coupled to the second jaw with its other end, in such a manner that the second jaw can be pivoted towards and away from the first jaw by use of said setting cylinder. The device is thereby provided with a coupling piece to be coupled to the end of the arm of the excavator by use of the hinge pin, while the first jaw is connected with the coupling piece in a point which, when seen in the longitudinal direction of the hinge pin, is located between the hinge pin and the point of attachment of the strut to the first jaw.
    Type: Grant
    Filed: June 15, 1990
    Date of Patent: November 5, 1991
    Assignee: Verachtert Beheer B.V.
    Inventors: Gertrudis M. G. De Gier, Jan R. Sytstra