Patents by Inventor Frederiks T. L. Visser

Frederiks T. L. Visser 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).

  • Panel with counterweight
    Patent number: 4334389
    Abstract: A panel with a counterweight for opening and closing and/or bridging an opening or a space. In a preferred embodiment the construction is such that when the panel is in its closed position, the counterweight lies substantially in the same plane as the panel and relative to the pivot the counterweight extends in opposite direction to the panel; when the panel is in the open position, the counterweight lies mainly in the same plane as the panel and relative to the pivot said counterweight extends in the same direction as the panel.
    Type: Grant
    Filed: March 11, 1980
    Date of Patent: June 15, 1982
    Assignee: Poly-Pro, B.V.
    Inventor: Frederiks T. L. Visser