Patent ID: 6454540
Filing Date: 2002-09-24
Classification: A62C,F04C,G05D

Abstract:
An apparatus in which metered quantities of one or more liquid chemical foamants are injected into at least one conduit assembly conveying a water stream so as to maintain a desired concentration of said chemical foamant in said water stream, comprising:at least one tank for holding a quantity of said liquid chemical foamants; at least one foam pump having an inlet port coupled to said tank and an outlet port coupled to said at least one conduit assembly; a hydraulic motor connected in driving relation to said at least one foam pump; a valve coupled with said hydraulic motor and a source of pressurized hydraulic fluid; a first sensor operatively coupled to said at least one conduit assembly to sense the rate of flow of the water stream flowing through said at least one conduit assembly and producing a first signal representative of said water flow rate; a second sensor operatively coupled to said at least one conduit assembly adjacent to said outlet port of said at least one foam pump to sense the pressure of both the water and foam chemical stream flowing through said at least one conduit assembly and producing a second signal representative of said water and foam chemical pressure; and a control system responsive to said first signal and said second signal for producing a signal for controlling a speed at which said hydraulic motor is driving said at least one foam pump, such that a desired quantity of the liquid chemical foamant in the water stream exiting said at least one conduit assembly maintains said desired concentration.