Abstract:
A chargeable portable fluid dispensing kit is not subject to all hazardous material regulations, and can dispense fluid in any orientation. In one embodiment, the kit includes a cylinder defining a total volume, and having a flexible diaphragm dividing the total volume into a dispensing fluid containing volume and a pressure volume. The cylinder has a first valve outside of the cylinder and in fluid communication with the dispensing fluid containing volume, and the cylinder has a second valve outside of the cylinder and in fluid communication with the pressure volume. Advantageously, a fluid can be introduced into the pressure volume through the second valve to increase the pressure in the total volume for dispensing a dispensing fluid disposed in the fluid dispensing volume through the first valve.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS  
         [0001]    Not Applicable  
         STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH  
         [0002]    Not Applicable  
         BACKGROUND OF THE INVENTION  
         [0003]    The invention relates generally to a fluid dispensing kit and more particularly to a fluid dispensing kit containing a pressure chargeable cylinder containing a dispensing fluid.  
           [0004]    There are numerous applications in which a dispensing fluid, such as a sprayable adhesive, fire retardant, insulation, sealant, and the like, is used at a site for any number of applications. For example, a dispensing fluid comprising a polyurethane foam is used with increasing frequency as a sealant in the building trades for sealing spaces between window and door frames. The foam is also used as an adhesive for gluing flooring and roof tiles. The polyurethane foam for such in situ applications is typically supplied as a one-component froth foam or a two-component froth foam.  
           [0005]    A one-component foam includes a dispensing fluid comprising both a resin and isocyanate. The fluid is supplied in a single pressurized container, and is dispensed from the container through a valve or gun attached to the container. A one-component foam is simple to use. Unfortunately, however, one-component foams have a short shelf life because the resin and isocyanate react over time in the single container.  
           [0006]    A two-component “froth” foam provides the foam components in separate containers. One component, such as polymeric isocyanate, fluorocarbons, and the like, is supplied in one pressurized container, while the other component, typically a resin, such as polyols, catalyst, flame retardants, and the like, is supplied in a second pressurized container. The components in the two component kit are typically dispensed simultaneously through a dispensing gun connected to both cylinders by hoses. The dispensing gun mixes the components as they are dispensed.  
           [0007]    Typically, two-component kits use pressurized cylinders  6 ″ to  10 ″ in diameter which are connected by the hoses to the dispensing gun. Generally, the cylinders weigh anywhere from 15 to about 30 lbs. and are pressurized with a pressurizing gas at pressures of about 200 psi gage at ambient temperature, 70° F. prior to shipping. The pressurizing gas mixes with the components in the cylinders, and must be an inert gas, such as nitrogen, that will not react with the dispensing fluid. One of the advantages of the two-component system is its relatively long shelf life resulting from the fact that the chemicals are not mixed until they encounter one-another in the dispensing gun.  
           [0008]    A two-component kit typically includes the two cylinders, each containing one of the foam components, the dispensing gun and hoses connecting the cylinders to the gun. These items are generally packaged in a cardboard container, box or carton and the carton is then used to hand carry the items to the site where the foam is to be dispensed. Because the chemicals contained within the cylinders are under a high pressure (i.e. greater than 40 psig), they are deemed hazardous material. Accordingly, the carton must house the cylinders in such a manner that extensive safety regulations are complied with during shipping. Complying with these safety regulations increases the costs of the kit, and limits available modes of shipping.  
           [0009]    A typical container for a two-component kit is a cardboard, fold-out box with a separate cardboard tray. The tray fits over the valved ends of the cylinders to hold the cylinders in place in the box during shipment and is integrated into the box such as by folding flaps fitting into tray slots at the box end adjacent the tray. The tray holds the cylinders and the box flaps hold the tray to the box. In the top of the tray, the hoses are placed in a coiled manner with the dispensing gun.  
           [0010]    To use, the operator opens the box end adjacent the tray and removes knock-out holes in the front face of the box. The hoses are then placed through the knock-out openings and tightened to the cylinder&#39;s valve fitting from above (discarding the protective shipping tubes) and the valves are opened. The cover is then folded back into the box to close the box and the hoses extend out of the box. Because the box end adjacent the tray has to be opened and closed to open and close the valves for use of the dispensing gun, the box is usually provided with a strap at the opposite box end which does not open. This means that the box is carried with the cylinders upside-down. However, this carton is perfectly acceptable for portable, hand-held, polyurethane froth foam in situ applications such as typically encountered in the building trades.  
           [0011]    Different packaging arrangements are used by different manufacturers. Many two-component kit packages use some form of tray with knock-out holes through which the hoses extend after the box is opened and the hoses attached to the cylinder&#39;s valved fitting. A two-component polyurethane froth foam box having cylinders equipped with “dip tubes” which extend through the outlet valve from the inside bottom of the cylinder is disclosed in U.S. Pat. No. 6,283,221. The dip tubes allow the cylinders to be placed upright in the box instead of upside down. This carton does not use a tray and has the hoses extend out the side of the box through knock-out plugs.  
           [0012]    Cylinders having dip tubes cannot consistently dispense a fluid in an inverted position, and cylinders without dip tubes do not consistently dispense a fluid in an upright position. Moreover, neither type of cylinder evenly dispenses a fluid in a tipped position, (i.e. between an upright and inverted position).  
         SUMMARY OF THE INVENTION  
         [0013]    The present invention provides a chargeable portable fluid dispensing kit that is not subject to all hazardous material regulations, and can dispense fluid in any orientation. In one embodiment, the kit includes a cylinder defining a total volume, and having a flexible diaphragm dividing the total volume into a dispensing fluid containing volume and a pressure volume. The cylinder has a first valve outside of the cylinder and in fluid communication with the dispensing fluid containing volume, and the cylinder has a second valve outside of the cylinder and in fluid communication with the pressure volume. Advantageously, a fluid can be introduced into the pressure volume through the second valve to increase the pressure in the total volume for dispensing a dispensing fluid disposed in the fluid dispensing volume through the first valve.  
           [0014]    A general objective of the present invention is to provide a fluid dispensing kit that is not subject to all hazardous material shipping regulations. This objective is accomplished by providing the cylinder with a second valve that can be connected to a source of pressurized fluid to pressurize the cylinder after the kit has been shipped.  
           [0015]    Another objective of the present invention is to provide a fluid dispensing kit that can consistently dispense a fluid in any orientation and can be charged using a non-inert gas. This objective is accomplished by providing a cylinder having a diaphragm dividing the cylinder volume into a dispensing fluid volume and a pressure volume. The diaphragm separates a compressed fluid pressurizing the cylinder volume from the dispensing fluid, and urges the dispensing fluid out of the first valve regardless of the orientation of the cylinder.  
           [0016]    The foregoing and other objects and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    [0017]FIG. 1 is a perspective cut away view of a two component fluid dispensing kit incorporating the present invention;  
         [0018]    [0018]FIG. 2 is a cross sectional view of a cylinder of FIG. 1;  
         [0019]    [0019]FIG. 3 is a partial cross sectional view of the cylinder of FIG. 2;  
         [0020]    [0020]FIG. 4 is a top view of the dispensing kit of FIG. 1 with the cover removed; and  
         [0021]    [0021]FIG. 5 is a bottom view of the dispensing kit of FIG. 1.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0022]    A two-component portable polyurethane foam spray kit  10  contained within a carton  12 , shown in FIG. 1, includes two cylinders  14 ,  16 . Preferably, one cylinder,  14  contains an “A” component, such as polymeric isocyanate, and the other cylinder,  16  contains a “B” component, such as polyol amine or resin. Formulations within each cylinder  14 ,  16  can vary significantly depending on the application. For example, adhesive applications produce a polyurethane foam which has very little, if any, “foam” while insulation applications use a formulation which produces a significant rise in the foam. Usually, portable, hand carried two-component polyurethane foam kits dispense the chemicals from the dispensing gun as a “froth” having a consistency or texture similar to that dispensed from an aerosol can of shaving cream. All such variations in the formulations of polyurethane and whether the chemicals are dispensed as a spray or froth are included within the scope of the present invention so long as the formulations are supplied in a portable, hand carried kit form.  
         [0023]    The cylinders  14 ,  16  are designated by a cylinder diameter, and in one preferred embodiment, the cylinder diameter is 71/2″. Two-component polyurethane foam kits incorporating the present invention can be supplied with cylinders having any diameter, such as between about 6 to 10″ in diameter without departing from the scope of the invention.  
         [0024]    In a preferred embodiment described herein, the cylinders  14 ,  16  have the substantially identical construction. Accordingly, only one cylinder  14  will be described with the understanding that the description applies to the other cylinder  16 . Although a two component kit having two cylinders as described below is preferred, substantially identical cylinders are not necessary to fall within the scope of the invention. For example, one of the cylinders can include a dip tube, such as known in the art.  
         [0025]    In a preferred embodiment, the cylinder  14  is an expansion tank, such as available from Amtrol Inc., West Warwick, R.I., which has been modified to include the valves  18 ,  20 , as described below. Referring to FIGS. 2 and 3, one embodiment of the cylinder  14  has a cylindrical body  22  that defines a volume. The volume is divided into a variable dispensing fluid volume  24  and a variable pressure volume  26  by a flexible diaphragm  28 . In the two component kit  10 , the dispensing fluid volume  24  of the cylinder  14  contains one of the “A” and “B” components, and the dispensing fluid volume in the other cylinder  16  contains the other of the “A” and “B” component  
         [0026]    The diaphragm  28  is secured in the cylinder  14  to separate the volume into the above described variable volumes  24 ,  26  using any methods known in the art. In one method, the cylinder  14  includes an upper cylindrical body  30  and a lower cylindrical body  32 . The upper cylindrical body  30  has as side wall  34  and an end wall  36  which is provided with an orifice  38 . The lower cylindrical body  32  has side wall  42  and an end wall  44  which is provided with an orifice  46 .  
         [0027]    A retaining (or clamp) ring  50  has an upper portion  52  and a lower portion  54 . The upper portion  52  of the retaining ring  50  has a bead (or internally facing groove)  56 . A lower edge  58  of the side wall  34  fits tightly over the region of the upper portion  52  above the bead  56 , and an upper edge  60  of the side wall  42  fits tightly over the lower portion  54  below the bead  56 . The side wall edges  58 ,  60  are welded to the retaining ring  50  to seal the seam between the upper and lower cylindrical bodies  30 ,  32 .  
         [0028]    The flexible diaphragm  28  is preferably formed of butyl rubber or other elastomer, and is disposed inside the lower cylindrical body  32 . The diaphragm  28  has an inward protruding bead (or groove)  62  on the interior surface thereof adjacent its circumferential free edge  64 . An inward protruding bead (groove)  40  in the side wall  42  corresponds to and mates with the bead  62  of the diaphragm  28 . The lower portion  54  of the retaining ring  50  contains an inward slanted portion  66  and an outward facing concave portion  68 . The concave portion  68  corresponds to and mates with the bead  62  of diaphragm  28 . In this manner, the free circumferential edge  64  of the diaphragm  28  is anchored to the lower cylindrical body  32 .  
         [0029]    The diaphragm  28  and lower cylindrical body  32  are then put on a grooving machine and a groove  70  is formed into the lower cylindrical body  32 , squeezing the diaphragm  28  to sealingly secure the diaphragm  28  to the lower cylindrical body  32 . The lower edge  34  of the upper cylindrical body  30  is then forced into fit with the region of upper portion  52  of the retaining ring  50  below the bead  56 . The lower edge  58  and upper edge  60  are welded (preferred), brazed or soldered to the bead  56  to seal the seam between the upper and lower cylindrical bodies  30 ,  32 .  
         [0030]    Advantageously, the diaphragm  28  separates the dispensing fluid from the pressurizing fluid which allows non-inert gases, such as air, to be used to pressurize, or charge, the cylinder  14 . Moreover, when the cylinder  14  is pressurized (i.e. the pressure volume of the cylinder  14  is filled with a pressurizing fluid, such as a liquid or gas), the diaphragm  28  urges the dispensing fluid out of the cylinder  14  through the orifice  38  regardless of the orientation of the cylinder  14 . Although a flexible diaphragm, as described above is preferred, any structure that separates the dispensing fluid from the pressurizing fluid, such as a rigid diaphragm, or piston, sealingly engaging the cylinder inner walls and slidable between the cylinder ends, can be provided without departing from the scope of the invention.  
         [0031]    A conventional air valve  18 , such as a Schrader valve is secured in the orifice  46  in the lower cylindrical body  32 , and permits the introduction of a pressurized gas, such as air, into the pressure volume  26  of the cylinder  14 . The air valve  18  can be connected to a pressurized source, such as an air compressor, gas cylinder, and the like, proximal the point of use of the kit to pressurize the cylinder  14  by filling the pressure volume  26  of the cylinder with high pressure air. Because the diaphragm  28  separates the pressurized gas in the pressure volume  26  from the dispensing fluid contained in the dispensing fluid volume  24 , any pressurized fluid, such as air, carbon dioxide, nitrogen, and the like, can be used regardless of the reactivity of the fluid with the dispensing fluid.  
         [0032]    A base  80  extends downwardly from the cylinder  14  surrounding the air valve  18  in the lower cylindrical body  32 . The base  80  is stamped from sheet metal and spot or resistance welded to the end wall  44  of the lower cylindrical body  32 . Advantageously, the base  80  protects the air valve  18 , and supports the cylinder  14  in an upright position when the base  80  is set on a supporting surface. Although a base protecting the air valve is preferred, the base can be omitted without departing from the scope of the invention. In addition other methods for protecting the air valve can be employed, such as by forming a cavity in the end wall surrounding the orifice formed in the lower cylindrical body to protect the air valve, locating the orifice in a side wall of the lower cylindrical body, surrounding the valve with a polystyrene annulus adhesively fixed to the cylinder, and the like, without departing from the scope of the invention.  
         [0033]    A conventional fluid dispensing valve  20  is secured in the orifice  38  in the upper cylindrical body  30 , and permits the dispensing fluid under pressure to be dispensed through a hose  82  and nozzle  84  connected thereto. The valve  20  opens and closes fluid communication of the dispensing fluid volume  24  of the cylinder  14  with a hose fitting  85 . A pressure relief (not shown) can also be provided for the cylinder  14  if required by safety regulations or concerns.  
         [0034]    A pair of guards  86  can be provided, as is known in the art, that extends upwardly from the cylinder  14  surrounding the fluid dispensing valve  20 . The guard  86  is formed from wire that shaped in a loop and welded to the end wall  36  of upper cylindrical body  30  or valve surrounding the fluid dispensing valve  20 . An opening  88  formed in the guard  86  can be used to lift the cylinder  14  and connect the cylinders  24 ,  16  together using a handle  90 . Although a guard  86 , or other structure, such as provided for protecting the air valve, protecting the fluid dispensing valve is preferred, it is not necessary to practice the invention.  
         [0035]    In the two component kit  10 , a hose  82 ,  92  is connected to each of the fluid dispensing valves  20 . Each hose,  82 ,  92  is connected at its opposite end to a dispensing gun  94 . An example of such a gun can be found in U.S. Pat. No. 5,462,204 to Finn, entitled “Foam Dispensing Gun” (incorporated by reference herein) for a description of a dispensing gun used in a two-component system. The invention, however, is not limited to any specific dispensing gun design.  
         [0036]    As shown in FIGS. 1, 4, and  5 , the carton  12  is a rectangular box, preferably formed from cardboard, such as is known in the art, and provides a convenient carrying case for the cylinders  14   16 , hoses,  82 ,  92 , and dispensing gun  84 . The carton  12  disclosed herein includes side panels  100  joined by front and rear panels  102 ,  104  and a closed bottom  106 . A cover  108  closes over the carton top and overlaps a portion of the front panel  102 . Openings  110  formed in the carton bottom  106  provide access to the air valves  18 . Hand openings  114  formed in the carton side panels  100  can be provided for use by the user to carry the kit  10 . The handle  90  is connected to the cylinders  14 ,  16 , and extends through an opening  112  formed in the cover  108  when the cover  108  is closed over the top. Advantageously, the cylinders  14 ,  16  can dispense fluid in any orientation, therefore any known carton can be used, such as known in the art for upright or inverted cylinders, without departing from the scope of the invention.  
         [0037]    The portable two component fluid dispensing kit  10  is assembled by slipping the cylinders  14 ,  16  into the carton  10 . The hoses  82 ,  92  can be connected to the fluid dispensing valves  20  for shipping or be loose for connection to the fluid dispensing valves  20  by the user at the point of use. In one embodiment, the hoses are coiled and fit between the cylinders  14 ,  16  and a box panel, or can be wrapped around or above the top of the cylinders. The handle is affixed to both cylinders  14 ,  16  through the opening  88  formed in the guard  86 . Of course, a conventional plastic carrying strap, or other type of handle, can be used without departing from the scope of the invention. The cover  108  is then closed over the carton top with the handle  90  extending through the top opening  112 . Advantageously, since the cylinders  14 ,  16  are not under high pressure, many of the hazardous material shipping requirements do not apply.  
         [0038]    Once the kit  10  is received at the point of use, the user pressurizes the cylinders  14 ,  16  by attaching a source of pressurized gas to the air valve  18  in each cylinder  14 ,  16 . Once the pressure in the cylinders  14 ,  16  reach a desired level, such as between about 80-150 psig at 70° F., the kit  10  is ready for use.  
         [0039]    The present invention provides significant advantages over the prior art. The cylinders  14 ,  16 , containing the dispensing fluids can be shipped without regard to regulations regulating hazardous material because the cylinders are not pressurized above pressures that trigger the regulations. In one embodiment, the cylinders  14 ,  16  can be pressurized proximal the point of use using a pressurizing fluid without regard to the reactivity of the pressurizing fluid with the dispensing fluid because the dispensing fluid and pressurizing fluid are separated in the cylinders.  
         [0040]    While there has been shown and described what are at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention defined by the appended claims. For example, the kit can be a single component fluid dispensing kit containing only one cylinder without departing from the scope of the invention. Therefore, various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention.