Patents by Inventor Frank J. Demo

Frank J. Demo 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).

  • Secondary supply power referenced interlock circuit
    Patent number: 5821641
    Abstract: A device for enabling and disabling the supply of power from a power source to a computer, the power source having a primary side and a secondary side, the device including an interlock switch connected to the computer, the interlock switch selectably positionable between open and closed positions; and two optocouplers coupled in parallel, both of which are referenced to the secondary side of the power source. When the interlock switch is closed, the first optocoupler is active. This enables the supply of power from the power source to the computer. When the interlock switch opens, the first optocoupler shuts off. This disables the supply of power from the power source to the computer. Further when the interlock switch is opened, the second optocoupler is saturated. This overrides the regulation feedback circuitry from regulating the power supplied by the power source driving the power outputted to the computer to zero. When the interlock switch is closed, the second optocoupler operates in the linear region.
    Type: Grant
    Filed: July 30, 1996
    Date of Patent: October 13, 1998
    Assignee: Compaq Computer Corp.
    Inventors: Frank J. Demo, Edward R. Stanford