Patents by Inventor Darryl Lee Robertson

Darryl Lee Robertson 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).

  • Post office box system and apparatus for indicating post office box occupancy
    Patent number: 6307472
    Abstract: A networked architecture for indicating node usage or occupancy comprising a plurality of nodes each movable between an unoccupied condition and an occupied condition, a plurality of sensor devices each movable from an inactive condition to an active condition in response to movement of one of the nodes from the unoccupied condition to the occupied condition, and indicator apparatus defining a plurality of indicator elements each for emitting a stimulus in response to movement of one of the sensor devices from the inactive condition to the active condition.
    Type: Grant
    Filed: October 21, 1999
    Date of Patent: October 23, 2001
    Inventor: Darryl Lee Robertson