Patent Publication Number: US-9421560-B2

Title: Method and apparatus to deliver a fluid mixture

Description:
This application claims priority from U.S. provisional application No. 61/510,218, the disclosure of which is incorporated herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to apparatus for delivering a fluid material (such as those used in construction and renovation including a mastic, an adhesive such as a masticated rubber, a caulking such as an acrylic latex, a sealant such as a two part foamable material, a sealant, insulation and the like) to a point of application for the purpose of sealing cracks, gaps and openings in the structure of, or ducting in, homes, commercial buildings and the like to reduce the infiltration of air, water or other substances. More preferably, this apparatus relates to a method for mixing at least two fluids and delivering the fluid material produced from the at least two fluids to a point of application. 
     BACKGROUND 
     Systems for mixing a two component system and applying the mixture are known. In such systems, each component is drawn from a container and fed through a pump and mixed in a hand held spray gun. Due to the use of the pumps, the apparatus is heavy and requires clean up after use. In particular, the pumps and conduits should be rinsed to flush the component therefrom to prevent fouling of the equipment. 
     SUMMARY 
     In accordance with this disclosure, an apparatus for mixing and applying a two component or multi component system is provided. In one aspect, external drive members, such as peristaltic pumps, which act on the outer surface of a flexible conduit, are utilized. One advantage of this design is that the drive member and most of the flow path of the components do not have to be cleaned after each use. For example, if a mixer nozzle is provided in a gun at the end of the flow path of the individual conduits, then only the mixer nozzle needs to be cleaned or replaced after each use. Accordingly, cleanup is substantially simplified and fouling of the equipment may be avoided. 
     In accordance with this aspect, there is provided a mixing and dispensing apparatus comprising:
         (a) a flow path comprising at least two conduits, at least a portion of each of which is flexible, each conduit having an inlet end connectable to a source of fluid and an exit end;   (b) a drive member adapted to act externally on the flexible portions;   (c) the flow path further comprising a mixer downstream from the exit ends and in fluid communication therewith;   (d) a discharge mechanism comprising a nozzle downstream from the mixer and in fluid communication therewith whereby the nozzle comprises a portion of the flow path and a hand grip portion wherein the hand grip portion is useable to direct the nozzle at a target surface whereby the fluids, once mixed, may be applied to the target surface; and,   (e) a first actuator operatively connected to the drive member.       

     In one embodiment, the drive member may comprise at least one peristaltic pump. 
     In another embodiment, the actuator may be provided on the discharge mechanism proximate a handle. 
     In another embodiment, the apparatus further comprises an inlet port connectable to a source of pressurized gas and in flow communication with the flow path, whereby, when a source of pressurized gas is attached to the inlet port, the pressurized gas is useable to assist in driving fluid through the flow path and out the nozzle. The source of fluid may comprise at least two containers and an inlet port connectable to a source of pressurized gas is provided on at least one of the containers. Alternately, or in addition, the inlet port may be provided upstream of the mixer and a second actuator may be operable to cause gas to flow through the mixer when the flow of fluid therethrough has ceased, whereby mixed fluid is removed from the mixer and nozzle. 
     In another embodiment, the discharge mechanism further comprises a gas flow line having an inlet end connectable with a source of pressurized gas and an outlet end, and a second actuator is operable to cause gas to flow through the gas flow line whereby the target surface maybe cleaned before application of the mixed fluid. 
     In another embodiment, the apparatus further comprises a back flow preventer upstream of the mixer. The back flow preventer may be provided between the exit ends and the mixer. 
     In another embodiment, the mixer may be a static mixer. 
     In another embodiment, each of the at least two conduits has a different internal diameter. The fluids may be mixed in a particular ratio and the internal diameters may be dimensioned based on the ratio in which the fluids are to be delivered to the mixer. 
     In another embodiment, the drive member comprises a first driver to act externally on the flexible portion of one conduit and a second driver to act externally on the flexible portion of a second flexible and the drive members operate at different speeds. The different speeds may be selected so that the desired proportions of the fluids are delivered to the mixer. 
     In another embodiment, each conduit is connectable in fluid communication with a different pressurizable container and a member for applying different pressures to each pressurizable container may be provided. The different pressures may be selected so that the desired proportions of the fluids are delivered to the mixer. 
     In another embodiment, the source of fluid comprises at least two containers and the apparatus further comprises a weigh scale for each container wherein the weigh scale is operatively connected to the drive member whereby the drive member is adjustable so that the desired proportions of the fluids are delivered to the mixer. 
     In another embodiment, the apparatus further comprises a heating member provided along at least a portion of the flow path. The heating member may comprise a heated passage through which a portion of the flow path extends and/or a resistive heating member. 
     In another embodiment, the source of fluid comprises collapsible containers. 
     In another embodiment, the drive member comprises a drive portion operative connected to the flow path and a drive motor, the source of fluid comprises containers and the apparatus further comprises a first housing for receiving containers of the fluid, a portion of the flow path extending from the containers towards the mixer and the drive portion, the first housing has an openable lid. The first housing may be insulated. A second housing containing the drive motor may be provided. The second housing may be positioned with respect to the first housing such that the drive motor has a portion that extends from the second housing into the first housing and is drivingly engaged with the drive portion. 
     In accordance with this aspect, there is provided a pressurizable container comprising an openable rigid wall container, an interior volume for receiving a fluid container at least a portion of which is flexible, an inlet port connectable with a source of compressed fluid and an outlet in communication with the volume. 
     In one embodiment, the pressurizable container further comprises two openable compartments and each compartment is operable at a different pressure. 
     In another embodiment, the pressurizable container further comprises a heating member. 
     In accordance with this aspect, there is also provided a pressurizable container comprising a fluid container at least a portion of which is flexible, a fluid outlet and an inlet port connectable with a source of compressed fluid and an outlet in communication with an expandable member provided in the fluid container. 
     In accordance with this aspect, there is also provided a first fluid container for a first fluid and a second fluid container for a second fluid, at least a portion of at least one of the fluid containers is flexible, each fluid container having a fluid outlet, and an inlet port connectable with a source of compressed fluid and an outlet in communication with one of the fluid containers. The pressurizable container may further comprise a heating member. Each fluid container may be operable at a different pressure. 
     In accordance with another aspect, pressure may be applied to the container for the fluid or fluids that are used. This pressure may provide part or all of the motive force to cause the fluid to flow through the apparatus. For example, the fluid may be provided in a pressurizable container. Various designs for pressurizable containers may be used. The pressurized gas may be applied directly to the head space of a container, to an expandable balloon or the like provided in a container, to the interior cavity of a container that has one or more flexible containers therein, or to drive an internal piston or the like. Accordingly, for example, as pressurized gas is applied to the head space of a container, the pressure in the head space will cause fluid to be driven from the container. 
     In a preferred embodiment, both a pressurized fluid and an external drive member are utilized. Each may apply 10-90% of the motive force. Preferably, one provided 25-75% of the motive force and the other provides 75-25% of the motive force. More preferably, each provides about 50% of the motive force. 
     In some cases, the components require mixing in other than a 1:1 ratio. Different mixing ratios maybe achieved by utilizing different diameter conduits, a gear box or the like to adjust the relative rate of rotation of an external drive member that utilizes a single drive motor, utilizing different motors operating at different speeds, applying different pressures to the storage containers or a combination thereof. 
     In accordance with another aspect, one or more of the fluids may be heated such as by heating the storage container or the conduit through which the fluid flows. 
     In accordance with another aspect, a telescoping and/or articulated delivery wand maybe utilized. A camera and/or a distance sensor may be provided to assist in applying the product produced by the apparatus. 
     In accordance with another aspect, an apparatus may be designed to apply a single component system. In such a case, only a single storage container is required. Such an apparatus may utilize any of the features disclosed herein. 
     It will be appreciated that a method and apparatus in accordance with this disclosure may use any one or more of these aspects. 
    
    
     
       DRAWINGS 
       In the detailed description, reference will be made to the following drawings, in which: 
         FIG. 1  is a schematic drawing of an apparatus according to one embodiment; 
         FIG. 2  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 3  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 4  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 5  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 6  is a side view of a support structure according to one embodiment; 
         FIG. 7  is a perspective view of an alternate support structure; 
         FIG. 8  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 9  is a schematic drawing of a pressurizable container according to one embodiment; 
         FIG. 10  is a perspective view of two fluid containers according to one embodiment; 
         FIG. 11  is a perspective view of two fluid containers according to another embodiment; 
         FIG. 12  is a schematic drawing of an alternate apparatus according to another embodiment; and, 
         FIG. 13  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 14  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 15  is a schematic view of an articulated wand according to another embodiment; 
         FIGS. 16 a -16 c    are alternate embodiments of optional nozzles; 
         FIG. 17  is a schematic view of an telescoping wand according to another embodiment; 
         FIG. 18  is a schematic drawing of a pressurizable container according to another embodiment; 
         FIG. 19  is a schematic drawing of a pressurizable container according to another embodiment; 
         FIG. 20  is a perspective view from the front of a particular embodiment of the apparatus; 
         FIG. 21  is a perspective view from the rear of the apparatus of  FIG. 20 ; 
         FIG. 22  is a perspective view from the front of the apparatus of  FIG. 20  with the lid open; 
         FIG. 23  is a top plan view of the apparatus of  FIG. 20  with the upper portion of the housing removed; 
         FIG. 24  is a cross-section along the line  24 - 24  in  FIG. 20 ; 
         FIG. 25  is a perspective view of pressurizable containers that may be used with the apparatus; 
         FIG. 26  is a perspective view from the front of an optional gun that may be used with the apparatus; 
         FIG. 27  is a perspective view from the rear of the gun of  FIG. 26 ; 
         FIG. 28  is a cross-section along the line  28 - 28  in  FIG. 27 ; 
         FIG. 29  is a perspective view from the front of the gun of  FIG. 26  with the flexible blow off nozzle oriented in a different direction; 
         FIG. 30  is an exploded view of an exemplary peristaltic pump; 
         FIG. 31  is a simplified drawing of the apparatus showing the collapsible containers, the applicator gun and the flexible conduits extending between the collapsible containers and the applicator gun with the housing and drive mechanism removed; 
         FIG. 32  is an exemplary hose bundle that may be used; 
         FIG. 33  is a schematic drawing of an alternate apparatus according to another embodiment; 
         FIG. 34  is a perspective view of a weigh scale that may be used in any embodiment; and, 
         FIGS. 35-38  are schematic drawings of alternate fluid containers which utilizes a piston to drive fluid from the container. 
     
    
    
     DESCRIPTION OF VARIOUS EMBODIMENTS 
     Various processes and apparatus will be described below to provide an example of each claimed invention. No process or apparatus described below limits any claimed invention and any claimed invention may cover processes and apparatus that are not described below. The claimed inventions are not limited to processes and apparatus having all the features of any one process or apparatus, or to features common to multiple or all of the processes or apparatus described below. It is possible that a process or apparatus described below is not an embodiment of any claimed invention. 
     Referring to  FIG. 1 , an exemplary delivery and mixing apparatus is exemplified. As shown therein, the delivery apparatus comprises first and second pressurizable containers  12 ,  14  (see for example  FIG. 25 ), a mixer  16 , a nozzle  18 , first and second conduits  20  and  22 , each of which extends between a respective pressurizable container  12 ,  14  and mixer  16 , and a drive member  24 . Accordingly, fluids contained in pressurizable containers  12 ,  14  may be conveyed through conduits  20 ,  22  to mixer  16 , wherein the fluids are mixed, and then dispensed through a nozzle  18 . 
     It will be appreciated that nozzle  18  may be provided at the downstream end of downstream extension wand  80  or gun  110  (see for example  FIGS. 26-29 ) or at another location spaced from mixer  16 . As exemplified in  FIG. 16 a   , nozzle  18  may have an outlet that is transverse to the longitudinal length of nozzle  18 . As exemplified in  FIG. 16 b   , nozzle  18  may have an outlet that is at an angle to the longitudinal length of nozzle  18 . As exemplified in  FIG. 16 c   , nozzle  18  may have an outlet that is parallel to the longitudinal length of nozzle  18 . 
     Each fluid container may hold, e.g. from 1-2 liters of fluid up to, e.g., 20-25 liters of fluid. Accordingly, the containers may be relatively light and could be portable, e.g., carried in a hand-held caddy or worn on a back pack. The conduits, or at least a portion thereof, are preferably flexible, (e.g., flexible plastic tubing) in which case a support structure, such as exemplified in  FIGS. 6 and 7 , is preferably provided to house an actuator and enable a user to control the location at which the material produced from the mixed fluids is deposited. Accordingly, it will be appreciated that the entire apparatus may be portable. For example, a user may transport the pressurizable containers  12 ,  14  by hand carrying or wearing a back pack with the containers to a location where the material is to be applied. In such a case, a relatively short length of conduit (e.g., 1 to 20 feet, more preferable 3 to 12 feet and most preferably 4 to 8 feet) may be provided. Alternately, if the fluid containers are large, they may be positioned at a location and a sufficient length of conduit  20 ,  22  may be provided (e.g., 10 to 50 feet) to enable a user to treat a particular area. In such a case, all of the apparatus other than the containers  12 ,  14  may be portable. Alternately, as exemplified in  FIGS. 20-24 , the apparatus may be mounted on a caddy  112  so it may be wheeled to a desired location. 
     Caddy  112  may be of any design that will hold the apparatus. As exemplified, caddy  112  has rear wheels  114 , a front support  116  that is provided at or towards the front of horizontal support frame  118 . It will be appreciated that one or more wheels may be provided on or in lieu of front support  116 . A front bumper  120  may be provided. Bumper  120  may also assist in retaining the apparatus on caddy  112  during movement of caddy  112 . A handle  122  may be provided to assist in moving caddy  112 . Preferably, the caddy is provided with a mount  124  for the conduit  20 ,  22 , which may be a wrap. As exemplified in  FIG. 24 , conduit  20 ,  22  may be looped over mount  124 . Alternately, or in addition, conduit  20 ,  22  may be immediately behind front bumper  120  as exemplified in  FIG. 24 . 
     The fluids in pressurizable containers  12  and  14  may be any compounds utilized in the building arts. For example, the fluid in one of containers  12 ,  14  may be a mastic, a caulking, an adhesive, a sealant or other building product. The fluid in the other of containers  12 ,  14  may be a blowing agent, or, if the building product is produced from mixing two components, the second component. For example, one container  12 ,  14  may contain a polymeric methyl diphenol diisocyanate (PMDI) and the other container  12 ,  14  may contain mixed polyols, a blowing agent such as HFC 245fa, a catalyst, a surfactant and optionally flame retardants. Accordingly, when the fluids are combined in mixer  16  a spray foam insulation is produced. Another example would be to provide an acrylic latex, a polyacylic acid, surfactants, and stabilizer in one container  12 ,  14  and a plasticizer, a cross linking agent, and a solid base blowing agent in the other container  14 . Accordingly, when the fluids are combined in mixer  16  an acrylic spray foam material would be produced. Another example includes a two component paint. In some embodiments, a single container  12 ,  14  may be utilized. In such a case, the single container  12 ,  14  may contain a single material for caulking consisting of acrylic latex, a filler such as calcium carbonate, surfactant and optional colorant or a one component paint to provide a protective, functional, and/or decorative finish to surfaces. 
     It will be appreciated that the material produced by the apparatus may be produced by mixing three or more fluids together. In such a case, apparatus  10  may be adapted to include more than two containers  12 ,  14 . For example, one conduit  20 ,  22  may be provided for each fluid that is to be delivered to mixer  16 . Alternately, some or all of the fluids may be introduced to each other upstream of mixer  16 . For example, the conduits may include a “Y” joint to combine the conduits into a single conduit upstream of mixer  16 . Preferably, as exemplified in  FIG. 28 , the conduits  20  and  22  have exit ends that are connected directly to the mixer. 
     As exemplified in  FIG. 1 , drive member  24  utilizes first and second peristaltic pumps  26 ,  28  which are driven by a motor  30 . Any peristaltic pump known in the arts may be used. As exemplified in  FIG. 30 , peristaltic pump  26  comprises a base  126  to which rotating drive  128  is mounted. A conduit  20 ,  22  may be wound around the rotating drive  128 . When rotating drive  128  rotates, fluid is pumped through conduit  20 ,  22 . 
     In order to permit first and second peristaltic pumps  26 ,  28  to operate at different speeds, motor  30  may be drivingly connected to one of the peristaltic pumps  26 ,  28  by shaft  34  and optional gear box  32 . Accordingly, when motor  30  is operated, peristaltic pump  26  may be driven directly by motor  30  (e.g., a shaft may extend between motor  30  and the pump  26 ) to operate at a first speed. Peristaltic pump  28  may be driven via gear box  32  so as to operate at an alternate speed. It will be appreciated that, in an alternate embodiment, a gear box  32  may be provided between motor  30  and each of peristaltic pumps  26 ,  28 . The gear boxes  32  may be the same or different so that the pumps  26 ,  28  may operate at the same or different speeds. Gear box  32  may provide a fixed gearing or may provide a variable gearing so as to enable a user to adjust the speed of one or both of peristaltic pumps  26 ,  28 . It will be appreciated that, in an alternate embodiment, two motors of different speeds may be employed to drive each of the peristaltic pumps  26 ,  28  to provide the desired mix ratio between the materials in containers  12 ,  14 . 
     An advantage of using a peristaltic pump is that the pump operates externally on conduits  20 ,  22 . It will be appreciated that at least portions  36 ,  38  of conduits  20 ,  22  are flexible so that fluid therein is moved along the conduit as peristaltic pumps  26 ,  28  rotate. It will be appreciated that all of conduits  20 ,  22  may be flexible (see for example  FIG. 31 ). Further, peristaltic pumps  26 ,  28  may be rotary peristaltic pumps as exemplified or, alternately they may be linear peristaltic pumps. Other external drive members which may be utilized include stepper motors, servo motors, gear motors, axial flux motors, air pressure or compressed gas driven motors, hydraulic motors and internal or external combustion engines. 
     An advantage of using a peristaltic pump is that the fluids which are being conveyed do not travel through the pump. Accordingly, no clean-up of the pump is required after use of apparatus  10 . This is particularly advantageous if, for example, a sticky or tacky compound such as an adhesive or mastic is applied via apparatus  10 . In operation, apparatus  10  may be cleaned up by replacing conduits  20 ,  22  and washing or blowing out mixer  16  and nozzle  18 . Alternately, mixer  16  and nozzle  18  may also be replaced. In addition, pressurizable containers  12 ,  14  may be refillable or may be replaceable. Alternately, mixer  16  and nozzle  18  may be cleaned out by passing a gas therethrough after use, such as by using air line  86  as discussed subsequently. 
     A further advantage of the peristaltic system is that a back flow preventer or check valve is not needed for plural-component systems. When the peristaltic pump is in a stationary position, the pump may compress the conduit  20 ,  22  thereby preventing back flow and accordingly operating as a check valve. 
     It will be appreciated that one or more other back flow preventing means may be utilized. For example, a check valve  136  or the like may be provided immediately upstream of mixer  16  so as to prevent mixed fluid entering each line leading to mixer  16 . 
     As exemplified in  FIG. 1 , an actuator (e.g. trigger  40 ) is provided. Trigger  40  as exemplified is operatively connected to motor  30 . For example, trigger  40  may close a contact so as to complete a circuit to actuate motor  30 . Optionally, trigger  40  may be operatively connected to motor  30  so as to provide a variable level of power to motor  30 . Accordingly, for example, the more actuator  40  is depressed, the more power may be provided to motor  30  and therefore the faster peristaltic pumps  26 ,  28  may operate. 
     Optionally, as exemplified in  FIG. 1 , a pressure source  42  is provided in flow communication with first and second pressurizable containers  12 ,  14  via first and second pressure lines  44  and  46 . Accordingly, a pressurized gas may be provided to the head space  48  in containers  12  and  14  so as to assist in driving fluid out of containers  12 ,  14  and into conduits  20  and  22 . Accordingly, the motive force to drive the fluid through conduits  20 ,  22  to and through mixer  16  may comprise both drive member  24  and pressure source  42 . 
     The pressure source may be a source of compressed gas (e.g. a disposable canister of compressed gas or a refillable canister of compressed gas, e.g. carbon dioxide). Alternately, the pressure source may be a compressor, which may be operated by connection to an electrical grid or by a battery pack or a small internal or external combustion engine, or a small fuel cell. A similar member may be used to operate motor  30 . 
     It will be appreciated that a separate pressure source  42  may be provided for each container  12 ,  14 . Alternately, or in addition, pressure lines  44 ,  46  may have the same internal diameter or different internal diameters. Alternately or in addition, valves  56 ,  58 , which may be separable controllable may be provided (see for example  FIG. 5 ). Accordingly, differential pressures may be applied to each container  12 ,  14  or as to provide a different motive force. This may be utilized if one of the fluids is more viscous and/or the fluids are to be mixed other than in a 1:1 ratio. 
     Mixer  16  may be of various designs, and, preferably, is a static mixer. Accordingly, mixer  16  need not have any moving parts. Instead, the fluids in conduits  20 ,  22  may be mixed as they pass through a non-linear path in nozzle  16 . For example, nozzle  16  may include an internal helical member so as to define a helical path through which the fluids pass as they travel through mixer  16  and are thereby mixed. Other examples of mixtures which may be utilized include a rotating dynamic mixer comprised of one or more rotating Archimedean screws or a lobed mixer. 
     As exemplified, nozzle  18  is preferably provided on downstream end  50  of mixer  16 . Accordingly, nozzle  18  may be a one-piece assembly with mixer  16 . Accordingly, mixer  16  and nozzle  18  may be a single unit which can be washed, blown out or disposed of. 
     An alternate embodiment is exemplified in  FIG. 2 . In this embodiment, conduit  22  has a larger internal diameter than conduit  20 . Accordingly, if peristaltic pumps  26 ,  28  rotate at the same speed, then a greater quantity of fluid will be drawn through conduit  22  as compared to conduit  20 . Accordingly, it will be appreciated that by adjusting the internal diameter of conduits  20  and  22 , different proportions of fluids may be drawn from containers  12 ,  14  and mixed. Accordingly, instead of utilizing a gear box  32  to adjust the relative rate of rotation of peristaltic pumps  26 ,  28 , the desired mixing ratio of the fluids in containers  12  and  14  may be adjusted merely by utilizing different diameters for conduits  20  and  22 . Alternately, or in addition, different flow rates of the fluids may be achieved by applying different pressures to head space  48  of containers  12  and  14 . Accordingly, by applying a larger pressure in the head space of container  14  than compared with container  12 , a greater amount of fluid may be drawn through conduit  22 . Accordingly, in order to adjust the mixing ratio of the fluids in containers  12  and  14 , apparatus  10  may use a combination of one or more of differential pressures in containers  12  and  14 , different rates of rotation of peristaltic pumps  26 ,  28 , different internal diameters of conduits  20  and  22 . 
     In the alternate embodiment exemplified in  FIG. 3 , drive member  24  is not provided. Instead, the motive force to draw fluid through conduits  20  and  22  comprises pressure source  42 . It will be appreciated that, in this embodiment, the relative amounts of the fluids drawn through conduits  20  and  22  may be adjusted by adjusting the pressure applied to containers  12 ,  14  and/or adjusting the internal diameter of conduits  20  and  22 . 
     As exemplified in  FIG. 4 , the flow of fluid may be controlled via first and second valves  52 ,  54  which may be provided in first and second conduits  20  and  22  respectively. Valves  52 ,  54  may be actuated by actuator  40 . Preferably, each of valves  52 ,  54  are opened by a single actuator  40  however, a different actuator  40  may be provided for each valve  52 ,  54 . Actuator  40  may be drivingly connected to valves  52 ,  54  by any means known in the art and may utilize a mechanical linkage and/or electronic control (e.g. a solenoid). In one embodiment, valves  52 ,  54  are opened concurrently. Alternately, each of valves  52 ,  54  may be variably controllable so that, by adjusting the amount that valves  52  and  54  are opened, the amount of fluid drawn through conduits  20 ,  22  may be adjusted to provide, or assist in providing, the desired mixing ratio of the fluids in mixer  16 . The valves  52  and  54  may apply a force to the outside of a flexible portion of conduits  20 ,  22  thereby preventing the materials being delivered from coming into contact with the mechanism thus preventing fouling of the mechanism. 
     As exemplified in  FIG. 33 , valves  52 ,  54  may comprise abutment members  138  that compress the outside of conduits  20 ,  22  and may be driven my motors  52 ′ and  54 ′ 
     As exemplified in the alternate embodiment of  FIG. 5 , trigger  40  may also control third and fourth valves  56 ,  58  which are provided in pressure lines  44  and  46 . The valves  56  and  58  may apply a force to the outside of a flexible portion of pressure lines  44  and  46 . Accordingly, instead of providing a valve in conduits  20  and  22 , the flow of fluid through conduits  20  and  22  may be controlled by opening and closing pressure lines  44  and  46 . It will be appreciated that third and fourth valves  56  and  58  may be utilized in alternate embodiments, including the embodiment of  FIGS. 1-4 . Further, a single actuator  40  may control the operation of all valves as well as drive member  24 . Accordingly, control of the flow of fluid may be provided by one or more of the operating a valve in pressure lines  44 ,  46 , operating a valve in conduits  20 ,  22  and drive member  24 . 
     An alternate method which may be utilized to monitor or control the rate of delivery of fluid from containers  12  and  14  is weigh scale  140 . As exemplified in  FIG. 4 , weigh scale  140  comprises a first compartment  142  for removably receiving container  12  and a second compartment  144  for removably receiving a container  14 . Weigh scale  140  includes a base  146  and first and second sensors  148  and  150 . Sensors  148  and  150  may be any sensors known in the art. Sensors  148  and  150  provide an output. The output of sensors  148 ,  150  may be provided to motor  30  of peristaltic pumps  26 ,  28 . Accordingly, as fluid is removed from each container  12 ,  14 , the weight of the containers will be reduced. Accordingly, weigh scale  140  may provide real time data about the amount of fluid left in containers  12 ,  14  to, e.g. motor  30  which drives peristaltic pump  26 ,  28 . A processor or the like may also be included in the circuit. Accordingly, the processor may utilize the current weight of each container  12 ,  14  to determine if the fluids have been mixed in the correct proportion and to adjust the rate of one or both of the peristaltic pumps  26 ,  28  to ensure or assist in providing the correct ratio of fluids are delivered to the mixer  16 . Alternately, or in addition, a flow meter  152  may be provided in one or both lines  20 ,  22 . The flow meter may open or close conduits  20 ,  22 , based upon the signal provided from weight scale  140 , to assist in controlling, or to control, the rate at which fluid is delivered from each container to nozzle  16  and thereby control the mixing proportion of the fluids which are drawn from containers  12 ,  14 . 
     If conduits  20  and  22  are flexible, or at least portion thereof are flexible, then a support structure  60  is preferably provided so as to control and manipulate nozzle  18 . For example, as shown in  FIG. 6 , support structure  60  comprises a handgrip-shaped portion  62  which includes trigger  40 . Preferably, in this embodiment, mixer  16  is provided on handgrip-shaped portion  62  and nozzle  18  is provided on mixer  16 . Accordingly, a person may utilize support structure  60  to adjust the position of nozzle  18  so as to dispense the mixed fluid at a desired location. Conduits  20  and  22  may be of indefinite length and may extend from containers  12 ,  14  to support structure  60  (see for example  FIG. 31 ). This may provide a suitable length of conduit so a person may move about in a building and apply the mixed compound at a desired location. It will be appreciated that if drive member  24  is not provided on support structure  60 , then a control member (e.g., a wire or mechanical linkage) or the like may extend with conduits  20 ,  22  to drive member  24 . 
     An alternate support structure  60  is shown in  FIG. 7 . As shown therein, support structure  60  comprises an elongate member which includes mixer  16  and an elongate nozzle  18 . 
     In accordance with another aspect, apparatus  10  may be utilized to dispense a single fluid. Accordingly, as exemplified in  FIG. 8 , a mixer  16  need not be provided. Instead, a wand  66  or an elongate nozzle  18  as shown in  FIG. 7  may be used in place of a mixer  16 . 
     Also exemplified in  FIG. 8 , a container  12  may be provided with a first flexible container  64  provided therein. Conduit  20  conveys fluid from container  64  to wand  66  and nozzle  18 . Drive member  24  may be any of those previously disclosed herein. Pressure may be applied to container  12  by line  44  using any of the methods disclosed herein. Accordingly, for example, a peristaltic pump  26  may be utilized to draw or assist in drawing fluid, which may be pressurized or may be at atmospheric pressure, from container  12  and may be dispensed at nozzle  18 . 
     Pressurizable container  12 ,  14  may be rigid. As exemplified in  FIG. 1 , pressurizable container  12 ,  14  has a liquid provided therein and the fluid is pressurized by providing a pressurizable fluid (preferably a gas) into a portion of container  12 ,  14 , such as via line  44 ,  46 . As exemplified in  FIG. 1 , a pressurizable fluid is provided into the headspace  48  so as to increase the pressure within container  12 ,  14 , and thereby drive or assist in driving fluid from container  12 ,  14  out via conduits  20 ,  22 . 
     In an alternate embodiment as exemplified in  FIGS. 8 and 9 , container  12  may comprise a body portion  70  and an openable lid  72 , all of which are preferably rigid. The container is openable, such as removing lid  72  or pivoting or removing lid  72  so as to enable a flexible container  64  to be placed in body portion  70 . As exemplified, lid  72  is provided with a pressurized fluid inlet  74 , which may be at the downstream end of, e.g., first pressure line  44 . Flexible container  64  may be provided with an outlet  68  for the fluid therein. Outlet  68  may be in fluid communication with conduit  20 . An opening is provided in container  12  so that outlet  68  may be connected to conduit  20 . Accordingly, in operation, a pressurized source of fluid may be provided in communication with an internal cavity of container  12 , such as via inlet  74 . As the volume inside the container  12  is pressurized, pressure is applied directly on the outer surface of flexible container  74 . This will apply pressure to the fluid in container  64  thereby providing a motive force to force the fluid in container  64  out of outlet  68 . 
     It will be appreciated that the container  12  is preferably rigid, although part or all of the outer walls of container  12  may be flexible. It will be appreciated that if container  12  is rigid, all of the pressure which is applied to the interior of container  12  will apply motive force to all surfaces of container  64 . It will also be appreciated that only part of container  64  may be flexible although it is preferred that all of container  64  may be flexible. Accordingly, all of the pressure which is applied in container  12  may be applied to all of the exterior surface of container  64  to thereby provide an efficient means of driving fluid of outlet  68 . 
     It will be appreciated that each of containers  12 ,  14  may be similarly constructed or may be constructed utilizing different techniques disclosed herein. 
     Referring to  FIG. 10 , two flexible containers  64   a  and  64   b  may be provided. Container  64   a  may be provided in pressurizable container  14  and flexible container  64   b  may be provided in pressurizable container  12 . It will be appreciated that containers  64   a ,  64   b  may have different volumes, if, for example, the fluids contained therein are to be mixed in different proportions. Accordingly, flexible containers  64   a ,  64   b  could be sized so that one the fluid therein is mixed in the appropriate portions, both are emptied at the same time. 
     In an alternate embodiment as exemplified in  FIG. 11 , container  64   b  may be positioned partially or wholly within container  64   a , such as within cavity  76  (which may be an annular internal cavity) in container  64   a . Accordingly, container  64   a ,  64   b , may be provided within a single pressurizable container  12 ,  14 . It will also be appreciated that a single pressurizable container  12 ,  14  may house two or more separate flexible containers  64 . For example, as exemplified in  FIG. 18 , two flexible containers  64   a ,  64   b  may be provided as separate members in a single container  12 . When the cavity  106  inside container  12  is pressurized via line  44 , pressure is applied to each of containers  64   a  and  64   b  to dispense, or assist in dispensing, fluid into conduits  20 ,  22 . 
     In an alternate embodiment, as exemplified in  FIG. 19 , it will be appreciated that a fluid to be utilized may be provided in a container  12 ,  14  which has an expandable member  108  (e.g., a balloon) therein. In such an embodiment, container  12  is preferably rigid. A pressurized source of fluid  42  may be provided via a pressure line  44  to an inlet of container  12  which is in communication with the expandable member  108  which is provided internally in container  12 . Accordingly, when a pressurized fluid (e.g. air) is provided into the expandable member  108 , the expandable member  108  expands thereby indirectly applying pressure to fluid in container  12  and driving fluid out of container  12  into conduit  20 . 
     An alternate means of drawing fluid from containers  12  and  14  is shown in  FIG. 35 . As shown therein, a piston  154  is provided in an upper portion of each of containers  12 ,  14 . A seal  156  is preferably provided between the outer wall of piston  154  and the inner wall of container  12 ,  14 . Seal  156  is utilized to assist in preventing, or to prevent, fluid travelling upwardly past piston  154 . Each piston  154  is driven by a motor, e.g. a stepper motor, which is actuated by, e.g. actuator  40 . A position sensor  160  may be provided for monitoring the position of piston  154 , and accordingly, may be utilized to control the rate of movement of each piston so as to assist in maintaining, or to maintain, delivery of the fluid in the desired mixing ratio. Alternately, position sensor  160  may be utilized to provide information as to the amount of fluid in each of containers  12 ,  14 .  FIG. 36  shows an alternate embodiment in which a single stepper motor is utilized in place of the stepper motors of  FIG. 35 . 
     An alternate delivery method is exemplified in  FIG. 35 . As shown therein, piston  154  is provided in container  12 ,  14  with optional seals  156 . A position sensor  162  monitors the position of piston  154 . In this embodiment, sensor  162  utilizes a wire or other member which provides a variable signal as the length of wire or member  168  is extended. Accordingly, as piston  154  extends further into container  12 ,  14 , the length of wire or member  168  will increase. This increase in length will provide a change in the signal output by sensor  162 . This change in signal may be utilized to control the rate of delivery of fluid from container  12 ,  14  and/or to provide a readout of the amount of fluid still in container  12 ,  14 . 
     A further alternate means is shown in  FIG. 38 , as shown therein, one or more magnets  164  are provided in piston  154 . Sensor  166  is provided on the exterior of container  12 ,  14  and monitors the position of magnet  164 . Accordingly, the signal from sensor  166  may be utilized to control the rate of delivery of fluid from container  12 ,  14  and/or to provide a signal indicating the amount of fluid left in container  12 ,  14 . 
     An advantage of any of these designs which use a collapsible container is that air is not introduced into the same space as the fluid as fluid is withdrawn. Thus, the introduction of air into the fluid in conduits  20 ,  22  may be reduced. 
     In accordance with another embodiment, as exemplified in  FIG. 12 , the downstream portion of apparatus  10  may be articulated to move in two and, preferably, three dimensions. For example, as exemplified in  FIG. 12 , optional upstream extension wand  78  is provided downstream of mixer  16 . Articulated joint  82  is provided upstream of downstream extension wand  80 . Preferably, nozzle  18  is provided at the downstream end of downstream extension wand  80 . Accordingly, the fluid, after being mixed in mixer  16 , may travel through upstream extension wand  78 , through articulated joint  82  into downstream extension wand  80  and be ejected via nozzle  18 . The articulated joint may move along a single axis (e.g. it may be rotatable about an axis in a single direction with respect to downstream extension wand  80  (e.g., articulated joint  82  may move about an axis  84  that extends transverse to the longitudinal axis of upstream and downstream extension wand  78 ,  80 ). Alternately, articulated joint  82  may be operational in more than one plane. For example, it may be a spherical coupling member. Accordingly, downstream extension wand  80  may be movable in more than one plane with respect to upstream extension wand  78 . For example, downstream extension wand  80  may be movable in two planes transverse to the longitudinal axis of upstream wand  78 . 
     It will be appreciated that mixer  16  may be provided downstream from articulated joint  82 . It will also be appreciated that nozzle  18  may be the outlet of downstream wand  80 . 
     Alternately or in addition, as exemplified in  FIG. 15 , one or more cameras  96  or distance sensors may be provided on upstream and/or downstream extension wand  78 ,  80  and/or nozzle  18 . The camera may be utilized to enable a person (e.g. the person holding support structure  60 ) to view the area that is being treated via apparatus  10 . As exemplified in  FIG. 15 , the camera would permit a user to view joint  98 , positioned at a juncture of wall  100  and floor  102 , as, e.g., foamed insulation is deposited in joint  98 . The distance sensor may also be utilized to advise a person the distance between, e.g., nozzle  18  and the surface to which the material is being applied. This may enable a person to maintain nozzle  18  at an appropriate distance from the area or to adjust the amount of blowing agent or air so as to ensure that the composition has a desired degree of aeration to the target surface. For example, a microcontroller may optionally adjust the flow rate and nozzle position relative to a joint to be sealed based upon the angular position of the joint to be sealed relative to the nozzle, the distance between the nozzle and to the joint to be sealed, and the relative velocity of the wand relative to the joint to be sealed. 
       FIG. 13  exemplifies some additional optional elements which may be used with any of the embodiments disclosed herein. For example, as exemplified therein, containers  12 ,  14  are provided in a heating jacket  92  which is provided with a heating element  94 . Accordingly, heat may be applied to the fluids in containers  12 ,  14  so as to reduce the viscosity thereof and improve the ease of flow thereof. Heating element  94  may be an electrical resistance heating element. Alternately, it may be a source of a heated fluid or any other heating means known in the art (e.g., a blower as exemplified in  FIG. 33 ). The heat may be applied internally inside containers  12 ,  14  or by another means known in the art. 
     Alternately, as exemplified in  FIG. 14 , heating jacket  92  (e.g., a flexible hollow conduit as exemplified in  FIG. 32 ) which is provided with a heating element  94 , may be provided to heat the fluid as it flows through conduits  20 ,  22 . 
     Heating element  94  may utilize electrical resistive heating. For example, an electrical resistive heating element (e.g., a wire that may be provided as part of a tape) may extend longitudinally through jacket  92  or may be wrapped around one or more of conduits  20 ,  22 . An advantage of heating the conduits is that the fluid may continue to flow despite the outside temperature and, further, the flow rate may be maintained as a relatively uniform rate regardless of the outside temperature. An advantage of electrical resistance heating is that a low uniform heat may be provided along the entire length of conduits  20 ,  22 . Alternately, or in addition, heated air may be blown through heating jacket  92 . In such an embodiment, the heated air may also be used to heat gun  110 . Alternately, or in addition, gun  110  may be heated by other means, such as electrical resistance heating. 
     Air line  86  may be provided, preferably from pressure source  42 , so as to deliver air to the mixed fluid. Pressure source  42  may be a cylinder of compressed gas, a compressor or any other means known in the art. It will be appreciated that air line  86  may be provided upstream, downstream (see  FIG. 14 ) or to mixer  16  itself (see  FIG. 13 ). The amount of air which is provided may be selected so as to provide the desired degree of aeration to the mixed fluid. 
     Alternately or in addition, air line  86  may be used to deliver gas, e.g., compressed or pressurized air) to mixer  16  and nozzle  18  to flow the fluid out of mixer  16  and nozzle  18  so as to prevent the mixed fluid from curing therein and therefore requiring the replacement thereof. 
     Alternately or in addition, air line  86  may be used to deliver gas, e.g., compressed or pressurized air) to a clearance nozzle  130  provided on, e.g., gun  110  (see for example  FIGS. 26-29 ). Clearance nozzle may have an inlet  132  that is connectable in fluid communication with air line  86 . The clearance nozzle may be used to clean a work surface before a fluid or mixed fluid is applied thereto. Accordingly, an actuator may be provided, e.g., on gun  110 , to cause nozzle  130  to deliver a jet of gas as may be required. For example, the actuator may provide a signal to start a compressor. Alternately, it may open a valve  134  provided on or proximate clearance nozzle  130  (see for example  FIG. 33 ). Accordingly, air line  86  may be pressurized and a jet of air delivered whenever valve  134  is opened. Clearance nozzle  130  maybe flexible (see  FIG. 29 ) so that a jet of pressurized air may be directed at a work surface. 
     It will be appreciated that a different air line may be used to supply air to foam the mixture, to blow out mixer  16  and to provide the cleaning function. 
     Hopper  88  may be provided to deliver solid material via line  90  to the mixed fluid. It will be appreciated that line  90  may be in fluid communication with apparatus  10  upstream, downstream, or directly to mixer  16 . Hopper  18  may be utilized to supply solid material, such as glass microspheres (solid or hollow), expanded polystyrene beads, glass fibers, aluminium micro spheres or other IR reflective materials or the like. Such material may be utilized to reduce the density of the mixed fluid and thereby increase the velocity at the exit from nozzle  18 . 
     In any embodiment, an extension wand, such as upstream and/or downstream extension wands  78 ,  80  may be provided. The extension wand, which may be a telescoping or folding wand, may be 1 to 15 feet long, more preferably 2 to 10 feet long and most preferably 3 to 6 feet long. As exemplified in  FIG. 17 , upstream extension wand  78  comprises a telescoping wand having telescoping sections  104   a ,  104   b  and  104   c.    
       FIGS. 20-24  exemplify a particular portable apparatus. As shown therein, caddy  112  is provided with first housing  170  and optional second or electrical housing  172 . Housing  170  is provided with an openable portion, e.g. lid  174 . When opened, cavities  176  are exposed in which containers  12 ,  14  may be removably seated. In addition, housing  170  preferably also houses the fluid transport means (e.g. peristaltic pumps  26 ,  28 ). Accordingly, the fluid containers  12 ,  14  and the peristaltic pumps  26 ,  28  may be provided in a closed container which is preferably thermally insulated. 
     An optional heater  178  may be provided inside housing  170  to maintain the temperature of the fluid. This is particularly useful during winter when the area in which the apparatus is utilized may be cold. A sensor, such as thermodisc  180 , may be provided for monitoring the temperature in first housing  170 . Accordingly, the temperature to be maintained in first housing  170  may be preset on a thermostat and the temperature may be automatically maintained during use of apparatus  10 . Optionally, a blower  182  may be provided. Blower  182  may be used to ventilate and therefore cool the interior housing  170  if the temperature therein increases too much. 
     If fluid is withdrawn from containers  12 ,  14  by, or with the assistance of, pneumatic pressure, then housing  170  may be provided with a mount  184  to which a source of pressurized air and an optional regulator may be attached. 
     Optional second or electrical housing  172  may be provided at any particular location and is preferably provided immediately below a portion of housing  170 . Electrical housing  170  houses motors  30  which drive, e.g. peristaltic pumps  126 ,  128 . The power supply  186  for motors  30  may also be provided in housing  172 . An advantage of providing the electronics and motor  30  in a separate housing is that the heat generated by the power supply and/or the motor may be separately contained and may not provide heat to container  170 , which may otherwise overheat the fluid in containers  12 ,  14 . As exemplified in  FIG. 24 , if second housing  172  is provided below a portion of housing  170 , then the shaft from motor  30  may extent upwardly through an upper wall of second housing  170  and through a lower wall of first housing  170  so as to drive peristaltic pumps  26 ,  28 . 
     It will be appreciated that an apparatus or a method in accordance with this disclosure may use one or more of the features disclosed herein. For example, an apparatus may use one or more of the external drive member, such as the peristaltic pump, the weigh scale to control delivery of fluid from containers  12 ,  14 , the heating of the conduits from containers  12 ,  14  to the mixer  16  and/or heating the mixer  16 , the use of collapsible containers using any one or more of the fluid delivery mechanisms disclosed herein, the use of backflow preventers as disclosed herein, the use of gas to clear a work surface and/or to clean out mixer  16 , the use of flow lines of different diameters to control or assist in delivering the desired ratio of fluids to mixer  16  and the externally mounted power supply by utilizing a second housing  172 .