Patents by Inventor Horst Hopfner

Horst Hopfner 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).

  • Multimeter with at least three input connections and means for preventing errors due to the selection of an incorrect input connection
    Patent number: 5166599
    Abstract: In multimeters having a plurality of input connections there is a danger of the measuring conductors being incorrectly connected in such a manner that the setting of the measurement range switch does not correspond to the input connections to which contact is made. In order to avoid damage which may be caused by making an incorrect contact to the input connections, an electrically and/or mechanically acting disabling device is coupled to the measurement range switch for permitting a disabling of particular input connections. The disabling is carried out in such a manner that contact can always only be made to that input connection for receiving a test signal through the measuring conductors, to which a measurable variable is assigned that corresponds to the measurable variable set with the measurement range switch.
    Type: Grant
    Filed: September 3, 1991
    Date of Patent: November 24, 1992
    Assignee: ABB Patent GmbH
    Inventors: Karl Hochreuther, Gunter Roppelt, Herbert Ziegler, Robert Kindermann, Horst Hopfner