Patents by Inventor Marnie E. Rycroft

Marnie E. Rycroft 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).

  • Emergency lighting system with a DC sensing load relay
    Patent number: 5859499
    Abstract: An emergency lighting system has emergency light units operable by DC power and connected to a source of AC and DC power by the same conduit system. Power to the conduit system may be switched from AC to DC in the event of a power failure and a load relay module in the conduit system adjacent the light units senses the change to DC current and switches from an Ac load output to a DC load output to supply DC power to the emergency light units. The system will generally include both exit signs operable by both AC and DC power and emergency light units operable only by DC power.
    Type: Grant
    Filed: January 15, 1997
    Date of Patent: January 12, 1999
    Assignee: Lumacell, Inc.
    Inventors: Robert McAfee, Marnie E. Rycroft, Morteza Showleh