Abstract:
An improved fire-fighting device designed to allow variable positioning of a quenching agent dispensing point. The fire-fighting device also allows high quenching agent flow rates. The device uses an articulable boom arrangement and solid pipeline to achieve these advantages.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S)  
       [0001]    This application is a continuation of U.S. patent application Ser. No. 09/393,464, filed Sep. 19, 1999 for “Fire-Fighting System Having Improved Flow” by David R. Bissen, William F. Burch, and Lawrence P. Schmidt. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates to an improved device for use in fighting fires. More particularly, it relates to an improved device for conveying a quenching agent from the fire-fighting vehicle to an advantageous application point.  
           [0003]    To effectively contain and extinguish fires, it is necessary to accurately direct the flow of a quenching agent such that it makes contact with the source of the fire. This task is often made difficult by the inaccessibility of the fire&#39;s source caused by intervening obstacles or the heat radiating from the fire itself. Also, the fire is often not located near a quenching agent supply, and the quenching agent must be conveyed a substantial distance from its supply to the source of the fire. Prior art systems often employed either a telescoping boom or a water cannon to deliver quenching agent from a distant location. An exemplary device, employing a telescoping boom, is disclosed in U.S. patent application Ser. No. 4,875,526, issued Oct. 24, 1989 to Latino, et al. entitled “ROUGH TERRAIN, LARGE WATER VOLUME, TRACK DRIVEN FIRE-FIGHTING APPARATUS AND METHOD.” The prior art devices suffer from a lack of accuracy and dispensing range. The prior art devices also are incapable of conveying large flow rates of quenching agent.  
           [0004]    There is a need in the art for a fire-fighting vehicle having the ability to pinpoint the position of the quenching agent dispensing point from a remote location. Also, there is a need in the art for a fire-fighting vehicle capable of conveying large volumetric flow rates of quenching agent.  
         BRIEF SUMMARY OF THE INVENTION  
         [0005]    The present invention is an improved fire-fighting vehicle having an articulable boom for accurate positioning of a nozzle near a fire source. The improved fire-fighting vehicle includes a vehicle chassis for rotatably supporting a plurality of boom sections. It further includes a conveying pipeline having an inside diameter of approximately six inches or greater and allowing a quenching agent throughput of at least 3,000 gallons per minute. The improved fire-fighting vehicle also includes a nozzle connected to a distal end of the conveying pipeline at a distal end of the outermost boom section. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 is a perspective view of a fire-fighting vehicle in accordance with the present invention.  
         [0007]    [0007]FIG. 2 is an exploded perspective view of an inlet pipeline according to the present invention.  
         [0008]    [0008]FIG. 3A is a perspective view of a first boom section according to the present invention.  
         [0009]    [0009]FIG. 3B is an exploded perspective view of a first pipeline section according to the present invention.  
         [0010]    [0010]FIG. 4A is a perspective view of a second boom section according to the present invention.  
         [0011]    [0011]FIG. 4B is an exploded perspective view of a second pipeline section according to the present invention.  
         [0012]    [0012]FIG. 5A is a perspective view of a third boom section according to the present invention.  
         [0013]    [0013]FIG. 5B is an exploded perspective view of a third pipeline section according to the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0014]    [0014]FIG. 1 shows a perspective view of a fire-fighting system  10  according to the present invention. The fire-fighting system  10  includes a truck  12 , a boom  14 , a conveying pipeline  16 , and a nozzle  18 . The truck  12  acts as a support or a base for the boom  14 . The boom  14  supports and articulates the conveying pipeline  16 . The truck  12  provides the ability for the fire-fighting system  10  to be mobile and transported to a location near the vicinity of the fire. The boom  14  and the conveying pipeline  16  function to allow the dispensing point of a quenching agent (not shown) to be located near the fire source. The quenching agent is dispensed through the nozzle  18 , which is mounted at the outermost end of the boom  14 . Although the preferred embodiment, as shown in FIG. 1, shows the fire-fighting system  10  having a boom  14  and conveying pipeline  16  mounted on the truck  12 , in other embodiments the boom  14  and conveying pipeline  16  may be mounted on a stationary support. Also, in some embodiments a monitor (not shown) may be placed between the outermost end of the boom  14  and the nozzle  18  to adjust the spray direction of the nozzle  18 .  
         [0015]    The truck  12  includes a chassis  20 , outriggers  22 , a tank  24 , a pump  26 , three hose connectors  27   a ,  27   b ,  27   c , and a boom base  28 . The chassis  20  of the truck  12  provides the main structural support for supporting the boom  14  and the conveying pipeline  16 . The outriggers  22  extend laterally from the chassis  20  and impose a downward force on the surrounding ground. The outriggers  22  function to stabilize the truck  12  and prevent it from tipping during deployment of the boom  14  and conveying pipeline  16 . The tank  24  holds a supply of the quenching agent used to suppress or quench the fire. The quenching agent is commonly water or a fire retardant chemical foam.  
         [0016]    The quenching agent may also be supplied by a source external to the truck  12 . In this case, the quenching agent is supplied to the pump  26  from an external source (not shown) by connecting hoses between the external source and the hose connectors  27   a ,  27   b ,  27   c . The hose connectors  27   a ,  27   b ,  27   c  then couple to an eight inch manifold pipeline (not shown), which connects to the pump  26 . The pump  26  acts to move quenching agent through the conveying pipeline  16  and out the nozzle  18 . The base  28  provides a surface for mounting the boom  14 . The boom  14  includes a turret  30 , a first boom section  32  a second boom section  34 , a third boom section  36 , a first actuator assembly  38 , a second actuator assembly  40 , and a third actuator assembly  42 .  
         [0017]    In a preferred embodiment, the truck  12  includes a tank  24  for storing about 850 gallons of fire retardant chemical foam, and the water is provided by an external source. The tank is constructed from fiberglass using resins selected to be compatible with the fire retardant chemical foam. In a preferred embodiment, the truck does not include a tank for storing water. In a preferred embodiment the quenching agent is a mixture of approximately two to six percent by volume of fire retardant chemical foam in water. The foam is injected into the water supply using methods generally known to those of skill in the fire fighting devices art.  
         [0018]    The turret  30  of the boom  14  is mounted to the base  28  of the truck  12 . The turret  30  allows rotatable motion, about a vertical axis, of the boom  14  with respect to the truck  12 . As shown in FIG. 1, a proximal end of the first boom section  32  is pivotally coupled to the turret  30 . A distal end of the first boom section  32  is pivotally connected to a proximal end of the second boom section  34 . A distal end of the second boom section  34  is pivotally connected to a proximal end of the third boom section  36 . Although the preferred embodiment shown in FIG. 1 includes three boom sections, the boom  14  could include any number of boom sections.  
         [0019]    As shown in FIG. 1, the first actuator assembly  38  is connected between the turret  30  and the first boom section  32 . The first actuator assembly  38  extends or retracts to control the angular position of the first boom section  32  with respect to the truck  12 . The second actuator assembly  40  is coupled between the first boom section  32  and the second boom section  34  and controls the angular position of the second boom section  34  with respect to the first boom section  32 . The third actuator assembly  42  is coupled between the second boom section  34  and the third boom section  36  and controls the angular position of the third boom section  36  with respect to the second boom section  34 . An operator of the fire-fighting system  10  can control the position of the distal end of the third boom section  36  by controlling the positions of the turret  30 , the first actuator assembly  38 , the second actuator assembly  40 , and the third actuator assembly  42 . The position of the distal end of the third boom section  36 , where the nozzle  18  is located, determines the dispensing point of the quenching agent.  
         [0020]    The conveying pipeline  16 , as shown moving from left to right in FIG. 1, includes a feed pipe section  44 , a first pipe section  46 , a second pipe section  48 , a third pipe section  50 , a first pipeline joint  52 , a second pipeline joint  54 , and a third pipeline joint  56 . The first pipe section  46  is pivotally coupled to the feed pipe section  44  by the first pipeline joint  52 . The second pipe section  48  if pivotally coupled to the first pipe section  46  by the second pipeline joint  54 . The third pipe section  50  is pivotally coupled to the second pipe section  48  by the third pipeline joint  56 . A distal end of the third pipe section  50  is coupled to the nozzle  18 . The various pipe sections  46 ,  48 ,  50  are rigidly coupled to the respective boom sections  32 ,  34 ,  36 . During motion of the boom  14  by an operator, the pipeline joints  52 ,  54 ,  56  allow the pipe sections  46 ,  48 ,  50  to pivot along with the boom sections  32 ,  34 ,  36 . The pipeline joints  52 ,  54 ,  56  allow pivotal motion while maintaining a liquid seal such that the quenching agent does not leak out of the conveying pipeline  16 .  
         [0021]    The fire-fighting system  10  of the present invention allows an operator to manipulate the actuators and strategically position the nozzle  18  for maximum fire-fighting efficacy. The fire-fighting system  10  of the present invention also teaches a solid-walled pipeline having a large diameter that allows large quenching agent flow rates. The boom sections  32 ,  34 ,  36  are generally constructed from a high-strength steel giving them the necessary strength and durability to operate in the vicinity of a fire and the pipe sections  46 ,  48 ,  50  are generally constructed from aluminum to minimize the weight that the boom sections  32 ,  34 ,  36  must support.  
         [0022]    [0022]FIG. 2 is an exploded perspective view of the feed pipe section  44 . The feed pipe section  44  carries the quenching agent from the tank  24  to a proximal end of the first pipe section  46 . As shown in FIG. 2, moving from a proximal end (the end near the tank  24  holding the quenching agent) to a distal end, the feed pipe section  44  includes a pipe  60 , a rigid coupling  62 , a sealing ring  64 , a pipe elbow  66 , a fixed coupling  68 , a sealing ring  70 , a horizontal pipe  72 , a sealing ring  74 , a swivel coupling  76 , a pipe elbow  78 , a sealing ring  80 , a swivel coupling  82 , a pipe  84 , a swivel coupling  86 , and a sealing ring  88 . The feed pipe  44  is configured such that it allows rotation of the turret  30  about a vertical axis and pivotal motion of the first pipe section  46  without compromising the integrity of the feed pipe section  44 . In other words, the feed pipe section  44  must maintain a seal such that it will completely contain the quenching agent. The components of the feed pipe section  44  which allow these movements are the swivel couplings  86 ,  82 , and  76 . The swivel couplings  82  and  86  are mounted to the pipe  84  which is disposed in a horizontal plane generally parallel to the ground on which the truck  12  is supported. The swivel couplings  82  and  86  allow pivotal motion of the first pipe section  46  with respect to the feed pipe section  44 . The pipe elbow  78  turns the feed pipe section  44  ninety degrees such that the feed pipe section  44  runs toward the bottom of the truck  12 . The vertical pipe  72  runs through the center of the turret  30  and is disposed concentric thereto. The swivel coupling  76  allows the feed pipe section  44  to maintain integrity during rotation of the turret  30 . The remaining components of the feed pipe section  44  are fixed and connect to the tank  24  or other quenching agent source.  
         [0023]    [0023]FIGS. 3A and 3B show perspective views of the first boom section  32  and the first pipe section  46 , respectively. The first pipe section  46 , which is supported by the first boom section  32 , carries quenching agent from the distal end of the feed pipe section  44  to the proximal end of the second pipe section  48 . The first boom section  32 , shown in FIG. 3A, and the first pipe section  46 , shown in FIG. 3B, are illustrated with the proximal end on the left side of the figures. In other words, the quenching agent would move through the first pipe section  46  from the left side to the right side of FIG. 3B.  
         [0024]    As shown in FIG. 3A, moving from left to right, the first boom section  32  includes a proximal coupling  92 , three pipe supports  94   a ,  94   b ,  94   c , a boom body  96 , and a distal coupling  98 . The proximal coupling  92  of the first boom section  32  couples to the turret  30  on the truck  12 . The boom body  96  provides the main structural support for the first boom section  32 . The pipe supports  94   a ,  94   b ,  94   c  are welded to the boom body  96  and support the first pipe section  46 . The distal coupling  98 , shown at the far left in FIG. 3A, connects to a proximal end of the second boom section  34 . Both the proximal coupling  92  and the distal coupling  98  allow pivotal rotation of the first boom section  32  with respect to the adjacent boom sections.  
         [0025]    As shown in FIG. 3B, moving from left to right, the first pipe section  46  includes a pipe elbow  100 , a rigid coupling  102 , a sealing ring  104 , a pipe  106 , a rigid coupling  108 , a sealing ring  110 , a pipe elbow  112 , a rigid coupling  114 , a sealing ring  116 , a pipe elbow  118 , a swivel coupling  120 , and a sealing ring  122 . The first pipe section  46  is configured such that it allows for pivotal motion of the second pipe section  48  without compromising the integrity of the conveying pipeline  16 . In other words, the first pipe section  46  and the second pipe section  48  must maintain a seal such that they completely contain the quenching agent. The component of the first pipe section  46  that allows pivotal motion of the second pipe section  48  is the swivel coupling  120 . The pipe elbow  100 , shown on the left side of FIG. 3B, pivotally couples to the pipe  84  of the feed pipe section  44  using the swivel coupling  86 . The remainder of the recited components of the first pipe section  46  are then coupled together in an end-to-end manner and attached to the pipe supports  94   a ,  94   b ,  94   c  of the first boom section  32 .  
         [0026]    [0026]FIGS. 4A and 4B show perspective views of the second boom section  34  and the second pipe section  48 , respectively. The second pipe section  48 , which is supported by the second boom section  34 , carries the quenching agent from the distal end of the first pipe section  46  to a proximal end of the third pipe section  50 . Like FIGS. 3A and 3B, FIGS. 4A and 4B are illustrated such that the proximal end is on the left side and the distal end is on the right side of the figure.  
         [0027]    As shown in FIG. 4A, the second boom section  34  includes a proximal coupling  126 , pipe supports  128   a ,  128   b ,  128   c , a boom body  130 , and a distal coupling  132 . The proximal coupling  126  of the second boom section  34  is pivotally coupled to the distal coupling  98  of the first boom section  32  such that the second boom section  34  may pivot with respect to the first boom section  32 . The pipe supports  128   a l,  128   b ,  128   c  are mounted to the boom body  130 , which applies the main structural support of the second boom section  34 . The distal coupling  132  is pivotally coupled to a proximal end of the third boom section  36 .  
         [0028]    The second pipe section  48 , as shown from left to right in FIG. 4B, includes a pipe elbow  134 , a sealing ring  136 , a rigid coupling  138 , a pipe elbow  140 , a rigid coupling  142 , a sealing ring  144 , a pipe  146 , a rigid coupling  148 , a sealing ring  150 , and a pipe elbow  152 . These components are rigidly connected together in an end-to-end manner and function to convey quenching agent from a proximal end of the second pipe section  48  to a distal end of the second pipe section  48 . The pipe elbow  134 , shown on the far left side in FIG. 4B, is pivotally coupled to the pipe elbow  118  of the first pipe section  46  by the swivel coupling  120 . The second pipe section  48  is therefore capable of pivotal motion with respect to the first pipe section  46  without disturbing the integrity of the pipe line  16 . The various components of the second pipe section  48  are fixed to the pipe supports  128   a ,  128   b ,  128   c  of the second boom section  34 . The second pipe section  48  conveys quenching agent from the distal end of the first pipe section  46  to the proximal end of the third pipe section  40 .  
         [0029]    [0029]FIGS. 5A and 5B show perspective views of the third boom section  36  in the third pipe section  50 , respectively. The third boom section  36  and the third pipe section  50  are shown if FIGS. 5A and 5B with a proximal end on the left side and a distal end on the right side of the figures.  
         [0030]    As shown if FIG. 5A, the third boom section  36  includes a proximal coupling  156 , pipe supports  158   a ,  158   b ,  158   c ,  158   d , a boom body  160 , and a distal end  162 . The proximal coupling  156  pivotally couples to the distal coupling  132  of the second boom section  34  such that the third boom section  36  may pivot with respect to the second boom section  34  in the same general plane. The pipe supports  158   a ,  158   b ,  158   c ,  158   d  are coupled to the boom body  160  and act to support the third pipe section  50 . The distal end  162  of the third boom section  36  supports the nozzle  18 .  
         [0031]    The third pipe section  50 , as shown from left to right in FIG. 5B, includes a sealing ring  164 , a swivel coupling  166 , a pipe  168 , a rigid coupling  170 , a sealing ring  172 , a pipe elbow  174 , a rigid coupling  176 , a sealing ring  178 , a pipe  180 , a reducer  182 , and a flange  184 . The third pipe section  50  is configured such that it allows pivotal motion of the third boom section  36  and the third pipe section  50  with respect to the second boom section  34  and the second pipe section  48 . The third pipe section  50  must maintain a sealed coupling to the second pipe section  48  during pivotal movement of the third boom section  36  with respect to the second boom section  34 . The component of the third pipe section  50  that allows this pivotal motion is the swivel coupling  166 . The pipe  168  of the third pipe section  50  is pivotally coupled to the pipe elbow  152  of the second pipe section  48  by the swivel coupling  166 . The swivel coupling  166  of the third pipe section  50  allows the pivotal motion of the third pipe section  50  with respect to the second pipe section  48 . The pipe elbow  174  turns the third pipe section  50  ninety degrees such that the pipe  180  runs generally parallel to the third boom section  36 . More specifically, the pipe  180  of the third pipe section  50  gradually approaches a center line of the boom body  160  of the third boom section  36  as it traverses from left to right in FIGS. 5A and 5B. In other words, the distal end of the third pipe section  50  is closer to the center line of the third boom section  36  than is the proximal end.  
         [0032]    As shown at the right side of FIG. 5B, the reducer  182  and the flange  184  are coupled to a distal end of the pipe  180 . The flange  184  is coupled to the nozzle  18 . The various components of the third pipe section  50  function to convey quenching agent from a distal end of the second pipe section  48  to a distal end of the third pipe section  50 . The quenching agent then flows out through the flange  184  and into the nozzle  18 , which is the ultimate dispensing point for the quenching agent.  
         [0033]    During operation, an operator may manipulate the quenching agent dispensing point by changing the positions of the boom section,  32 ,  34 ,  36  with respect to one another and by rotating the entire boom  14  with respect to the truck  12  using the turret  30 . An operator may thereby position the quenching agent dispensing point in a position having the greatest fire combating efficacy. The device of the present invention allows the quenching agent to be dispensed at a point near the source of the fire without endangering equipment or fire fighting professionals.  
         [0034]    Once the operator has properly positioned the boom  14 , the pump  26  may be activated to convey quenching agent from the tank  24  (or other source) through the feed pipe section  44  to a proximal end of the first pipe section  46 , through the first pipe section  46  to a proximal end of the second pipe section  48 , through the second pipe section  48  to a proximal end of the third pipe section  50 , and through the third pipe section  50  to the nozzle  18 . The solid, articulable, conveying pipeline  16  also allows for maximum quenching agent flow rates.  
         [0035]    The conveying pipeline  16  may have any overall length that is desirable and allows for the necessary quenching agent flow rates. In preferred embodiments, the conveying pipeline  16  has a length of 85 feet, 110 feet, or 130 feet. Also, should be apparent to one of ordinary skill in the art that shorter or longer booms could also be used with present invention. The conveying pipeline  16  design of the present invention will adequately pump quenching agent through pipe of these overall lengths.  
         [0036]    In a preferred embodiment, the present invention utilizes a conveying pipeline  16  having an six or eight inch inside diameter. The motive force is generated using a single-stage centrifugal pump constructed from cast iron (pump body), stainless steel (impeller shaft), and bronze (impellers, clearance rings, and fittings). The pump  26  of the preferred embodiment is capable of generating a flow rate of 3000 gallons per minute at a pump discharge pressure of 150 pounds per square inch, a flow rate of 2100 gallons per minute at a pump discharge pressure of 200 pounds per square inch and a flow rate of 1500 gallons per minute at a pump discharge pressure of 250 pounds per square inch. To generate the above flow rates, the pump requires 470 horsepower input from the engine of the truck  12 . Typically, the engine of the truck  12  can provide about 500 horsepower.  
         [0037]    The conveying pipeline  16  of the fire-fighting system  10  of the present invention can support flow rates in excess of 3000 gallons per minute when the pump  26  can provide such flow rates. The pump  26  can provide a flow rate of 4,000 gallons per minute at 110 pounds per square inch pump discharge pressure when the quenching agent source is charged or pressurized to 10 pounds per square inch (e.g., a fire hydrant). This configuration allows the device of the present invention to generate a quenching agent volumetric flow rate of approximately 5,000 gallons per minute when the quenching agent source is sufficiently charged. The quenching agent flow rate, which may be modeled as laminar flow through a pipe, may be calculated using the following equation for ideal flow:  
       Q   =         π        (       Δ                 p     -     p                 g                 Δ       )            D   4         128                 μ                 l                             
 
         [0038]    where Q is the volumetric flow rate, Δp is the change in pressure between a pipe inlet and a pipe exit, ρ is the fluid density, D is the diameter of the pipe, μ is the fluid viscosity, and 1 is the length of the pipe. The above equation cannot be used to accurately calculate flow rates for the fire-fighting system  10  of the present invention for at least two reasons. The fire-fighting system  10 , which generates flow rates up to 5,000 gallons per minute, is operating at a Reynolds number well in excess of 4000, and thus the flow of quenching agent is turbulent, not laminar. Also, the conveying pipeline  16  of the fire-fighting system  10  is not an ideal pipe. Pressure losses occur in the pipeline  16  due to frictional forces, bends in the pipeline  16 , and irregularities at the pipe joints.  
         [0039]    The above equation, however, does accurately show the general effect of adjustments to one of the parameters on volumetric flow rate. As is apparent from this equation, the volumetric flow rate is strongly dependent on the diameter of the pipe. For example, an increase in the diameter of the pipe by a factor of two will result in an increase in the flow rate by a factor of sixteen (two to the power of four). It is apparent, therefore, that a system, such as that of the present invention, having an increased diameter pipe will greatly improve the overall quenching agent volumetric flow rate.  
         [0040]    As described herein, the preferred embodiment uses a pipeline having an inside diameter of at least six inches and preferably eight inches. It should be understood, however, that the teachings of the present invention would apply equally as well to a device using larger than eight inch pipeline. Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.