Patent ID: 7703543
Filing Date: 2010-04-27
Classification: A62C

Abstract:
1. A fire fighting foam dispensing system, comprising: a water inlet adapted to receive a flow of water; a first variable speed pump adapted to inject foam concentrate into the flow of water; a second variable speed pump adapted to inject foam concentrate into the flow of water; a foam outlet adapted to discharge fire fighting foam; a measuring apparatus adapted to measure flow rate in at least one of the water inlet and the foam outlet; a system controller adapted to detect the flow rate from the measuring apparatus, and activate the second variable speed pump only upon the measured flow rate exceeding a predetermined flow rate value; a first intermediate conduit in fluid communication with the first variable speed pump, the first intermediate conduit extending between the water inlet and the foam outlet; a second intermediate conduit in fluid communication with the second variable speed pump, the second intermediate conduit extending between the water inlet and the foam outlet; a first valve located in the first intermediate conduit; and a second valve located in the second intermediate conduit; wherein the system controller is adapted to open the second valve only upon the measured flow rate exceeding the predetermined flow rate value.