Patents by Inventor Frits Frey

Frits Frey 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).

  • CIRCUIT ARRANGEMENT FOR LIMITING A VOLTAGE
    Publication number: 20100116633
    Abstract: A circuit arrangement for enforcing an intrinsically safe situation in a hazardous zone features a first switching device that lies in the series arm and a second switching device that lies in the shunt arm. If a fault occurs that would violate the conditions of intrinsic safety, the first switching device is initially blocked and the second switching device is switched through with a time delay such that the output terminals are mutually short-circuited. In addition, a monitoring device is provided for monitoring the load conditions at the switching device arranged in the series arm.
    Type: Application
    Filed: March 12, 2008
    Publication date: May 13, 2010
    Applicant: STAHL SCHALTGERATE GMBH
    Inventors: Frits Frey, Manfred Kaiser