Compressed air foam system
First Claim
1. A system for supplying compressed air and foam solution to produce a fire stream comprising an aerated foam, said system comprisinga mixing means having a foam solution inlet, a discharge, and an air inlet,a fire stream delivery means constructed and arranged to receive fluid flow from the discharge of said mixing means,a fire pump for delivering water under pressure from a discharge thereof,a water supply conduit means for delivering water from the discharge of said pump to the foam solution inlet of said mixing means,water flow sensing means for sensing a flow rate of the water flowing through said water supply conduit means,a foam proportioner for delivering foam chemical into the water delivered by said water supply conduit means for making the foam solution,air conduit means for delivering the air to said air inlet of said mixing means,air flow sensing means for sensing a flow rate of the air flowing through said air conduit means,an air compressor for delivering the air at a discharge pressure to said air conduit means, said compressor having an inlet and a discharge,an inlet throttling valve means for varying a flow of air to said compressor inlet to thereby control the compressor discharge pressure, said inlet throttling valve means having a control chamber and a valve member responsive to pressure in said control chamber for varying the flow of air to said compressor inlet, andair flow control means for regulating the pressure of the air supplied to said control chamber of said inlet throttling valve means in accordance with the flow rate of the water sensed by said water flow sensing means and the flow rate of the air sensed by said air flow sensing means to automatically maintain the said flow rate of the air at a desired relationship to said flow rate of the water.
1 Assignment
0 Petitions
Accused Products
Abstract
A system supplies compressed air and foam to produce a fire stream comprising an aerated foam. The system includes a fire pump, an air compressor, a mixer, and a controller for automatically maintaining a desired ratio of air and water delivered from the mixer to a fire stream delivery device. An electronic control unit is arranged to sense both the flow rate of the water delivered by the fire pump and the air flow rate delivered by the air compressor, and modulates an air pressure signal used to vary the flow of air to the inlet of the air compressor so as to hold the air flow rate and the water flow rate at the desired ratio.
-
Citations
9 Claims
-
1. A system for supplying compressed air and foam solution to produce a fire stream comprising an aerated foam, said system comprising
a mixing means having a foam solution inlet, a discharge, and an air inlet, a fire stream delivery means constructed and arranged to receive fluid flow from the discharge of said mixing means, a fire pump for delivering water under pressure from a discharge thereof, a water supply conduit means for delivering water from the discharge of said pump to the foam solution inlet of said mixing means, water flow sensing means for sensing a flow rate of the water flowing through said water supply conduit means, a foam proportioner for delivering foam chemical into the water delivered by said water supply conduit means for making the foam solution, air conduit means for delivering the air to said air inlet of said mixing means, air flow sensing means for sensing a flow rate of the air flowing through said air conduit means, an air compressor for delivering the air at a discharge pressure to said air conduit means, said compressor having an inlet and a discharge, an inlet throttling valve means for varying a flow of air to said compressor inlet to thereby control the compressor discharge pressure, said inlet throttling valve means having a control chamber and a valve member responsive to pressure in said control chamber for varying the flow of air to said compressor inlet, and air flow control means for regulating the pressure of the air supplied to said control chamber of said inlet throttling valve means in accordance with the flow rate of the water sensed by said water flow sensing means and the flow rate of the air sensed by said air flow sensing means to automatically maintain the said flow rate of the air at a desired relationship to said flow rate of the water.
-
2. A system for supplying compressed air and foam solution to produce a fire stream comprising an aerated foam, said system comprising
means for mixing the air and the foam solution having a foam solution inlet, a discharge, and an air inlet, a fire stream delivery means constructed and arranged to receive fluid flow from the discharge of said mixing means, a fire pump means for delivering water under pressure from a discharge thereof, a water supply conduit means for delivering the water from the discharge of said pump means to the foam solution inlet of said mixing means, a foam proportioner for delivering foam chemical into the water delivered by said water supply conduit means for making the foam solution, air conduit means for delivering the air to said air inlet of said mixing means, an air compressor for delivering the air at a discharge pressure to said air conduit means, said compressor having an inlet and a discharge, and control means for automatically maintaining a set ratio of air flow to water flow to said mixing means including an inlet throttling valve means for varying a flow of air to said compressor inlet to thereby control a compressor discharge air flow rate, said inlet throttling valve means having a control chamber and a valve member responsive to pressure in said control chamber for varying the flow of air to said compressor inlet, air control means for regulating the pressure of the air supplied to said control chamber of said inlet throttling valve means including an air pressure regulator means having an air inlet means, an air outlet means, and a control means for varying an air outlet pressure of said air pressure regulator means, a first conduit means for communicating the compressor discharge pressure to said air inlet means of said air pressure regulator means, and a second conduit means for communicating the air outlet pressure of said air pressure regulator means to said control chamber of said inlet throttling valve means, and an electronic control unit for delivering control signals to said control means of said air pressure regulator means to vary the outlet pressure thereof, said air control means being constructed and arranged to vary the pressure of the air communicated by said second conduit means to said control chamber of said inlet throttling valve means to regulate the flow rate of the air delivered to said air inlet of said mixing means in accordance with the flow rate of the water delivered by said fire pump means to automatically maintain the rates of air flow and water flow to said mixing means at a desired relationship.
Specification