Patents by Inventor Hartmut Knappe

Hartmut Knappe 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: 4523251
    Abstract: An electronic apparatus has an input stage (11) with a binary signal output (19). This signal output is connected to a relay control circuit which deenergizes or energizes the relay (15) in dependence on the output signal (0 or 1). The relay (15) can be held in the energized condition over a wide voltage range, without being overloaded, by a periodically limited energizing current. This is achieved, by way of example, by energizing the relay via a semiconductor switching device (transistor 14) which can be switched on and off by a Schmitt trigger (12) connected to the binary signal output. A capacitor (17) charged in dependence on the energizing current flowing through the relay is used to override the signal from the binary output (19) to switch the transistor (14) via the Schmitt trigger (12) so as to periodically energize the relay (15) (FIG. 1).
    Type: Grant
    Filed: September 28, 1982
    Date of Patent: June 11, 1985
    Assignee: Erwin Sick GmbH Optik-Elektronik
    Inventors: Jurgen Erdmann, Karl O. Buchholz, Hartmut Knappe