Patents by Inventor Hans Landgraf

Hans Landgraf 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: 4376971
    Abstract: A system for protection against getting caught in automatically operable doors or windows, particularly of vehicles. Specific intervals of time within which the closing or opening door should reach a given position are preset. When the door does not reach one of these positions within the time allowed, the reversing motion is initiated or the cycle of motions is stopped. For this purpose, an electric signal generator coupled to the door motion delivers electric position signals when predetermined positions of the door are reached. An electric storage element is set by the position signals and after a predetermined time interval automatically reset, with the logic value of its output signal changing.
    Type: Grant
    Filed: January 27, 1981
    Date of Patent: March 15, 1983
    Assignee: Gebr. Bode & Co.
    Inventors: Hans Landgraf, Joachim Dorner, Siegfried Heinrich, Manfred Horn