Patents by Inventor Heiman S. Bollegraaf

Heiman S. Bollegraaf 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: 5193454
    Abstract: A baling press provided with a pressing box, a feed chute connected with the pressing box via a passage, at least two prepress valves. The prepress valves are each pivotable about a pivotal axis, provided with a flat wall which in closed position closes off the passage from the feed chute to the pressing box and in opened position is disposed in the wall of the feed chute, and with a surface substantially curved about the corresponding pivotal axis, which surface in closed position bounds the feed chute in axial direction. One of the prepress valves is provided with a connecting surface which in the closed position is curved about a pivotal axis of one other of the prepress valves. In that closed position, the connecting surface is disposed at a distance from the curved surface of said other prepress valve which is at most minor and substantially constant.
    Type: Grant
    Filed: February 4, 1991
    Date of Patent: March 16, 1993
    Assignee: H.S. Bollegraaf-Holding, B.V.
    Inventor: Heiman S. Bollegraaf