Abstract:
A Self-Sustaining Compressed Air Foam System that utilizes a vacuum proportioning blending console, delivering pre-determined amounts of fire pre-suppressant/suppressant foam concentrate with ratios from 0.01% to 6% and water when used in concert with a vacuum dispensing closure for tight head pails dispensing said foam concentrate that is plumbed to either an air operated pump or solar powered electric pump on the inlet side producing a pre-suppressant foam solution. A second blender/mixer/agitator conjoins an inert pressurized gas or air at the outlet of the pump variables to produce the finished pre-suppressant/suppressant foam product for various applications including structure protection in wild fire events. A special nozzle can be used as the applicator that reduces pressure/velocity of the finished foam to allow the user to work in confined areas and/or in areas that are normally out of reach of the foam stream projected.

Description:
[0001]    This application is based on Provisional Application Ser. No. 61/144,173 filed on Jan. 13, 2009. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to sustainable foam fire protection equipment, in particular, an apparatus for generating and delivering pre-fire suppressant foam for use in fire protection. 
         [0003]    Any discussion of prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common knowledge in the field. 
         [0004]    Making a clear distinction between urban, rural and wildland fire protection responsibilities has been difficult in recent years due to California&#39;s rapid population growth and accompanying residential, commercial and industrial development in these diverse geographical settings. As the number of people and structures has grown and spread to areas of flammable vegetation with steeper topography, a fire protection problem of unprecedented magnitude has developed. California between 1984 to 1993 lost 75 people to wildfires and over 7000 structures were destroyed resulting in over 3 billion dollars in damage. And lives, property and natural resources lost to wildfire will continue to increase, paralleling this human migration. The values at risk, represented by people and property sharing the tinder-dry steep slopes of California&#39;s “Wildland/Urban Interface” (WUI) illustrates the most difficult, dynamic wildfire protection challenge in the world. With the exception of firefighting professionals (who are often spread to thin) and their equipment (which has difficulty navigating this particular terrain), there are few products available which can adequately protect structures in the path of a wildfire. Federal and State officials claim: “ultimately, property owners are responsible for their own fire protection”. The “Self-Sustaining Compressed Air Foam System” eliminates the product technology gap between the garden hose and the fire department. 
         [0005]    It is estimated that 42 million structures are at risk to wildfire across the United States. 5 million structures are at risk in California alone. When wildfire breaks out in the WUI, pushed by high winds and extreme temperatures, available firefighting resources often spend their time saving lives and evacuating people, leaving the fire to burn unchecked until reinforcements arrive. 
         [0006]    The fact that water is not the perfect tool for extinguishing fire has long been acknowledged and discussed. It&#39;s a cumbersome fluid and it is costly to install water mains large enough for required flow. The installation and maintenance of fire hydrants, procurement and required care of fire engines and all the accompanying apparatus, make water an increasingly valuable natural resource and a very expensive extinguishing agent. 
         [0007]    The use of foam additives to fight fire dates back to England in the late 1800&#39;s. The British Navy experimented with foam and compressed air in the 1930&#39;s. And The U.S. Navy was using compressed air foam (CAF) against flammable liquid fires in the 1940&#39;s. In the 1960&#39;s do-it-yourself car wash businesses were using compressed air foam systems with low pressure and small diameter hoses and nozzles. 
         [0008]    In the mid 1970&#39;s the Texas Forest Service developed a water expansion system known as the “Texas Snow Job’, and this pioneering “Class A” compressed air foam system used a pine soap derivative as a foaming agent. By the 1980&#39;s, research by the U.S. Bureau of Land Management led to modern design features of rotary air compressors, centrifugal pumps and direct injection foam proportioning systems. The basic premise of compressed air foam technology is the addition of a minute percentage of a soap-like concentrate to water as it runs through a standard pumping system, and then to inject compressed air as the water discharges from the pump. The soap-like concentrate reduces the surface tension of the water, then the air disturbs the solution to create a bubble structure which is an effective barrier against flying embers and flames. CAF systems received national attention in 1988 during the Yellowstone Park wildfires when an applied blanket of compressed air foam successfully protected Old Faithful Lodge. 
         [0009]    Today, common design features of CAFS are targeted for the professionally trained firefighter. Those systems require training and maintenance, as well as utilizing diverse foam concentrates for several different fire fighting applications (i.e., wildland vs. liquid fuel fires). Foam from CAFS can also be used as a carrier for both agricultural and hazardous material applications: this means that a pesticide or decontamination agent can be added to the mix of water and foam concentrate to take advantage of foams characteristic to cling to what it is applied to rather than running off as water would. These types of foam applications require very different proportioning rates of water and foam concentrate, and necessitate the need for trained and qualified operators. Even CAFS designed exclusively for wildland fires require training to operate correctly. Moreover, the cost of operating a professionally designed CAF is high. Internal combustion engines running pumps and compressors require fuel and maintenance and discharge large quantities of water very quickly. And the amount of foam concentrate needed is directly proportional to the gallons per minute discharge rate of these systems. Foam concentrate is very expensive. Professional CAFS often run at the rate of 175 gallons per minute (gpm) or more. The Hale HPX 200 is an example of an average professionally designed CAF system with a gpm rate as high as 300 gallons. To produce a structure protection quality foam would require 2.4 gallons per minute of foam concentrate, which would cost nearly 27 dollars per minute to produce foam. Consequently, firefighters use their CAFS on the low end of the proportioning scale (0.2-0.3%), rather than the 0.6 to 0.8% proportioning rate required for long-term structure protection. 
         [0010]    Conversely, CAF systems designed with very low (5-20) gpm discharge rates are pre-mixed pressurized vessels that are limited in size and haven&#39;t the capacity to protect the average size structure in the WUI. American Fire and Tri-Max are two companies with this design and it is my belief they work on the principle of Cummins&#39; U.S. Pat. No. 4,318,433 and the principle of an ejector tube and aeration/mixing chamber with foam discharged and propelled by an attached compressed air cylinder. They produce a quality foam product intended for immediate fire suppression or the protection of a very limited area in size and, are designed for professionals. 
         [0011]    Another company, Intelagard, designed a backpack system U.S. Pat. No. 5,623,995 (Smagac) that required pouring foam concentrate into a tank of water. The two fluids then needed to be stirred for uniformity, and the system could subsequently be activated by the opening of several valves. Intelagard&#39;s current design U.S. Pat. No. 6,155,351 (Breedlove, Smagac) appears to have a metering pump attached to a separate foam concentrate tank capable of pumping specific proportioned amounts of concentrate into a water stream to produce a wide spectrum of finished foam types. However, it should be noted that there appears to be an error in that patent&#39;s description of that specific component. At one point, under the heading of “Agitation Apparatus” U.S. Pat. No. 6,155,351; column 9, lines 47, 49, 53 the component is referred to as an “agitation apparatus” 118, while at another site in the patent under the heading, “Source of Foam Fluid”; column 6, lines 39, 62 the same component is referred to as a “metering pump” 118. But regardless of that error in Intelagard&#39;s patent language, the use of a metering pump is unnecessary and wasteful. The problem with a metering pump is that it uses stored air energy, a needless process if not relying on compressor air to operate the metering pump(s). Property owners untrained in the art of pre-fire suppression equipment need the simplest and most efficient use of stored air energy when engaging a wildfire with a self-contained CAFS. 
         [0012]    Venturi type proportioners utilize another engineering principle common in the proportioning of foam concentrate to water in compressed air foam systems. These types of systems offer a mechanical means for adjusting proportioning ratios and are geared to the fire fighting professional as they require training and understanding of the fluid requirements for fighting fire. Teske demonstrates an adjustable venture type in U.S. Pat. No. 5,255,747, as does Kroll in U.S. Pat. No. 4,474,680. 
       BRIEF SUMMARY OF THE INVENTION 
       [0013]    The object of the present invention overcomes the complexities associated with prior art. The present invention eliminates the need for an extra tank for foam concentrate or other amendments. The present invention also eliminates the need for pre-mixing a water/foam concentrate solution with the simple addition of a vacuum-dispensing-closure for tight head pails. 
         [0014]    Another object of the present invention eliminates the need for individual (separate) components that proportion and blend foam concentrate within a water stream. The present invention accomplishes that task with the addition of a vacuum-proportioning-blending-console. 
         [0015]    Another object of the present invention is to eliminate the need for a self-contained compressed air foam system that either (1) depends solely on a pre-mixed, pressurized vessel; or (2) relies on a fossil fuel run engine to operate a pump required for drawing fluids necessary for producing foam solutions. 
         [0016]    Another object of the present invention is to eliminate waste, splash-back and the potential for over application of the foam blanket without having to reduce system pressure when relying on a large diameter single bored nozzle and applying foam in close quarters. 
         [0017]    The present invention delivers foam concentrate from the 5-gallon tight head pail which is received from the manufacturer. The pail&#39;s original cap is replaced with a new cap, comprised of a port (which is connected to a metering valve) and a vent to atmosphere. This allows the pail to be inverted and attached to a compressed air foam system. The inverted pail is then attached to the branch of a tee, a component of the vacuum-blending console. Upstream of the branch of the tee is a constrictive plate. The foam concentrate is introduced downstream of the constrictive plate, via the metering valve, through the branch (vacuum port) of the tee which is adjacent to the vena contracta, created by the constrictive plate. A pressurized air/inert gas operated pump, or solar powered transfer pump, draws the water-foam solution through the vacuum-blending console up through said pump(s) to the pump outlet. At this juncture, a pressurized air/inert gas insertion port is attached to propel the foam solution through an agitator where the foam solution is expanded to its finished foam state to exit at a nozzle. 
         [0018]    This unique nozzle is designed to reduce the trajectory of a standard single bore nozzle to which it is attached and divide the stream into four separate streams. This novel construction maintains system-working pressure while eliminating product waste due to splash back and over application of the foam product. This allows the user to apply foam in close proximity to a structure&#39;s eaves, or in confined areas such as under decks or carports. 
         [0019]    The intention of this invention is to practice sustainability. Therefore, a solar powered transfer pump with necessary photovoltaic panels, inverters, energy storage components and other electrical items can be substituted for the pressurized air operated pump. With the solar powered variant, stored air energy need only be used for inserting pressurized air agitating and propelling the foam solution at the pump outlet to the application nozzle. 
         [0020]    In summary the structures and methods comprising the present invention eliminate a component of existing CAFS. The present invention also combines and simplifies the proportioning and blending processes/methods of producing pre-suppression foam, while reducing waste (over application) at the nozzle. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  illustrates in block diagram view the options of the present invention and the components that make up the embodiments. 
           [0022]      FIG. 1   a  illustrates in block diagram view the components of the preferred embodiment. 
           [0023]      FIG. 2  illustrates in block diagram a view of the present invention and the components that make up the optional embodiment. 
           [0024]      FIG. 3  illustrates a perspective view of the control panel. 
           [0025]      FIG. 4-5  illustrates a perspective view of a tight head pail with vacuum dispensing closure. 
           [0026]      FIG. 6  illustrates an inside perspective and side view of the vacuum-dispensing closure. 
           [0027]      FIG. 7  illustrates a perspective view of the vacuum-blender console. 
           [0028]      FIG. 8  illustrates a perspective view of the pressurized-air injector/agitator apparatus. 
           [0029]      FIG. 9  illustrates a side view perspective of the nozzle with large bore single stream shutoff adapter. 
           [0030]      FIG. 10  illustrates a front view perspective of the nozzle. 
           [0031]      FIG. 11  illustrates a perspective of a detachable handle for the nozzle. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    In  FIG. 1 , the self-sustaining compressed air foam system  10  illustrates in broken-lines an alternative to the preferred embodiment for the source of stored air energy  40  and stored solar energy  100 . The implementation of each of these variations is subject to selection by one skilled in the art of the available technology to create a specific implementation of the system component. 
         [0033]    Overview:  FIG. 1 , the self-sustaining compressed air foam system comprises a source of stored energy  40 , 110  attached to a control panel  20  via energy supply lines  32 , 32   a  that attaches to a regulator  28 , 29  or switch S that operates a pump  80 , 120  and pressurized air injector/agitator  123 , 123   a  that is connected by a pipe, tube or hose  24 , or wire  24   a  to said pump  80 , 120  that draws water via pipe, tube or hose  72 , 74  from a source of water or tank  50 . A second foam concentrate container  160  intersects pipe  72 , 74  via a tube  62 , 64  at the branch of a tee  70 , 70   a  that conjoins the water line  72 , 74  with the foam concentrate dispensing tube  62 , 64  to form a water/foam concentrate solution that is drawn up through the pump  80 , 120  to pump outlet at the attached air injector/agitator  123 , 123   a  where foam solution is expanded by injected air via line  24 , 24   a  to air insertion port  124 ,  FIG. 8 , to form a foam and is set in motion via pipe or hose to exit at a nozzle  90 ,  90   a  that can be used to apply the finished foam as a pre-suppression foam for fire protection. 
         [0034]    Control panel: Types and variations of stored energy  40 ,  110  are channeled to the control panel  20 . In the preferred embodiment,  FIG. 3  depicts supplied stored air energy through line  32  from compressed air cylinders  40   FIG. 1  or other inert gas such as nitrogen. Pressurized gas is prevented from activating the system with on/off valve  27  that is normally closed. System pressure is registered at gauge  25   a . Open valve  27  and high pressure air is channeled to regulators  28 ,  29  via line  21   a  where system pressure is reduced to working pressure and exits at lines  21   b ,  21   c  and registers said working pressure on gauges  25   b ,  25   c  wherein said working pressure air is channeled to operate pump  80  via line  22  and to operate air insertion agitator  123  via line  24 . The solar variance would require air supply line  22  to be closed and switch S closed on control panel  20  to supply stored electric energy via line  26  wherein air supply line  24  is shutoff with bypass valve  224   FIG. 3  to open line  24   a  and supply pressurized air to air insertion agitator  123   a.    
         [0035]    Process Components: Compressed air foam systems in general use one of two methods for producing a foam solution. One is to pre-mix water with a foam concentrate the other is to have a separate or second tank to that of water containing foam concentrate with a pump like device to inject the foam concentrate into a water stream.  FIG. 4 , of the preferred embodiment and its variant eliminates the need for the aforementioned methods. The nippled  162   a  and vented  164  vacuum dispensing closure  161  as depicted in relation to an inverted tight head pail  166  that contains a manufactured foam concentrate that dispenses said concentrate via metering valve (not shown) through tube  162  and attached at nipple  162   a    FIG. 1 , that is attached to the branch of the vacuum blending console tee  70 , 70   a  that draws water from tank  50  when valve  27   FIG. 2  is opened to activate the air operated pump  80   FIG. 1 . The solar variance would require air supply line  22  to be closed prior to opening valve  27  and a switch S closed on control panel to supply stored electric power  110  to pump  120  that would then draw foam concentrate from line  162  and water from line  74  simultaneously to be conjoined at the vacuum blending console tee  70   a  to form a blended foam solution prior to being drawn into pump  120  and exiting the air insertion agitator  123   a  where solution is expanded to form a finished foam and is propelled via pipe or hose to exit at a nozzle  90   a  that can be used to apply finished foam as a pre-suppression quality foam for fire protection. 
         [0036]    As  FIG. 5 , illustrates, the vacuum dispensing closure  161  with threaded dispensing nipple  162   a  that receives a metering valve (not shown) preset to allow flow of a pre-determined rate of foam concentrate from tight head pail  166  in proportion to the gallons per minute being drawn from water supply line  72   FIG. 1  once air operated pump  80  is activated. The vacuum dispensing closure vent  164  is designed to allow a continuous stream to be drawn from the threaded vacuum dispensing closure nipple  162   a  and prevent tight head pail  166  walls from collapsing under vacuum pressure created at vacuum blending console tee  70 . The exposed first end of vent  164  is barbed  167  to attach a tygon extension hose to control panel  20  where it is attached to a shutoff valve (not shown) to prevent contamination/insects from clogging vent tube  67  to atmosphere. The second end of vent  164  is above the fluid level in the inverted tight head pail allowing for vent to atmosphere. This design is such because the system may not be used and perforating the tight head pails body  166  to atmosphere would oxidize the foam concentrate and reduce its shelf life of two years.  FIG. 6  illustrates a perspective view of the design inside the vacuum dispensing closure  161  as well as a side view. The outside diameter of the closure has merlons  168  for gripping when tightening or loosening the closure. A gasket  169  of a pvc type membrane to ensure a leak tight seal. The relationship of the dispensing nipple  162  and vent  164  to the overall architecture are demonstrated and will be manufactured so as to be an integral part to the closure body  161 . The closure  161  in its entirety will be made of high-density polyethylene with industry standard buttress type threads  163   FIG. 4  for joining with tight head pail. 
         [0037]    For the user of this self-sustaining compressed air foam system simplicity is required when needed to produce structure protection quality pre-suppression foam. Panic could lead to misuse if a user needs to think of what ratio of foam concentrate to water is needed with an approaching wildfire. Therefore all components are engineered to deliver a specific ratio of foam concentrate to water that will produce a consistent pre-suppression quality foam. Foam concentrate manufacturers recommend a ratio of concentrate to water to be in the range of greater than 0.5% to less than or equal to 1%  FIG. 7  illustrates a perspective view of the vacuum-proportioner/blender console  70 ,  70   a  made of plastic or metal, tubing or pipe, it eliminates the need for thinking about ratios. Said console is pre-engineered to deliver the correct proportion (proprietary ratio) of foam concentrate to water and is part of the water/foam concentrate solution feed line  72 , 74  and depicts one of several designs consisting of a body  77  with a first end having a constrictive plate  73  designed to reduce the water flow to a specific rate from the water tank  50  to the pump  80 , 120  wherein said constrictive plate  73  is proceeded by a void with an inlet port  74  directly above and adjacent to the constrictive plate  73  to create a vacuum that draws foam concentrate via tube  62 , 64  into the water stream for blending through the spheres  76  that are contained in situ by impediments  75 . The threaded second end attaches directly to the upstream side of a pump  80 ,  120  to channel the water/foam concentrate solution to the next component in the process. 
         [0038]    The final component in the process to produce a pre-suppression quality foam product is depicted in  FIG. 8 . The air-insertion agitator  123 ,  123   a  that consists of a plastic or metal pipe or tube that&#39;s threaded on both ends with the first end having an air-insertion port  124  to receive pressurized air from line  24 , 24   a  that agitates and expands the foam solution as it passes through a static-mixer  125  that produces the finished foam product. That static-mixer is an off-the-shelf item produced by several manufacturers and is held in place by impediment  126  and exits second end to proceed via hose or pipe in an expanded foam state to an applicator or nozzle  90 . 
         [0039]    Pressure Reducing Applicator: The design of the pressure-reducing-applicator  90 , FIGS.  9 , 10  eliminates the need for the user of this system to manually reduce the working pressure when applying foam in confined areas (heat traps) such as under decks or in and around carports or where applying foam in close proximity to fuels or structures and the potential for over application and fluff off of foam blanket is possible. The pressure-reducing applicator attaches to a standard inline shutoff adapter  300  for standard firefighting hose. The inline shutoff adapter  300  serves as a nozzle for the system when applying pre-suppression foam to broad areas 50 to 75 feet away such as roofs or in the canopy of trees. When close-up foam application work is required the user simply attaches the pressure-reducing-applicator  90  by hand after shutting down the flow of foam with the lever  302  on the inline shutoff adapter  300 . No tool is required and to re-activate the foam stream simply pull the lever handle  302  back on the inline shutoff adapter  300 . 
         [0040]    This set-up is un-wieldy without the use of a handle or grip.  FIG. 11  illustrates a detachable grip  200 . Expensive pistol grip type nozzles designed for professional firefighters offer little for a homeowner seeking a specific bubble structure in finished foam. Open bore type nozzles are the preferred method and with the detachable grip  200  greater control and comfort are accomplished. The handle  202  of the grip  200  allows the bolt  206  to be attached to the base nut  214  of the retainer ring  204  that surrounds the outside diameter of the inline shutoff adapter  300  just behind the shutoff lever  302  at point  306 . Turning the handle  202  counterclockwise will extract the bolt to a point that allows the retainer to be place around the body of the inline shutoff adapter  300  and to secure the grip  200  simply turn the handle clockwise to tighten the bolt that contacts the body of the inline shutoff adapter  300  causing the retainer ring  204  to secure the assembly. This inexpensive grip is placed into position prior to activating the system. The removable grip  200  can be made of plastic or metal or both but, must be capable of withstanding operating forces of the application, over torquing the handle  202  could cause failure at the shoulder/stop  212  therefore the handle  202  will be made of a durable high impact polycarbonate/acrylonitrile butadiene styrene while the retainer ring  204  will be made of a more flexible polypropylene or aluminum. The bolt  206  will be of steel with a hardness greater than the inline shutoff adapter  300  which is aluminum allowing the steel bolt or stud to seat itself in the aluminum body of the adapter. 
         [0041]    In summary, the present self-sustaining compressed air foam system makes use of a tight head pail to supply foam concentrate to a vacuum-proportioning-blender attached to a water source and choice of stored energy operated pump(s) that draw water and foam concentrate as a solution to exit the pump(s) where a pressurized inert gas insertion port is attached to set in motion the foam solution through an agitator that expands the foam solution to exit a nozzle as a finished pre-suppression quality foam for the protection of structures in the event of an approaching wildfire. 
         [0042]    While I have shown certain embodiments of the present invention, it is to be understood that it is subject to many modifications and changes without departing from the spirit and scope of the appended claims.