Patents by Inventor Frederick M. Gray

Frederick M. Gray 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).

  • Receiver for A.C. electrical supply signalling arrangement
    Patent number: 4392121
    Abstract: A receiver for an a.c. electrical supply signalling arrangement of the kind in which information is transmitted by impressing on the supply voltage waveform voltage reductions which bridge the zero crossings in the waveform wherein detection by the receiver of an impressed voltage reduction is achieved by comparing the integral of the supply voltage over a period immediately preceding a voltage zero crossing when a voltage reduction is present with a corresponding integral obtained when no voltage reduction is present.
    Type: Grant
    Filed: December 2, 1980
    Date of Patent: July 5, 1983
    Assignee: The General Electric Company Limited
    Inventors: Frederick M. Gray, Charles G. Leedham
  • Systems for transmitting information in an alternating current electricity supply system
    Patent number: 4254403
    Abstract: A system for transmitting information in an alternating current supply system wherein information is transmitted by reducing the instantaneous value of the supply voltage during a corresponding period in each of a selection of cycles of the supply voltage, the selection of cycles determining the information transmitted. To minimize disturbance of the system voltage the period of alteration includes a voltage zero. The alteration is effected by closing a switch connected across the system for the period the voltage reduction is required.
    Type: Grant
    Filed: August 6, 1979
    Date of Patent: March 3, 1981
    Assignee: The General Electric Company Limited
    Inventors: Leonardo Perez-Cavero, Michael W. A. Cross, Geoffrey Fielding, Frederick M. Gray