Abstract:
A valve assembly is disclosed for use in an aerosol spray can capable of spraying viscous materials or materials with large particulates without clogging or packing like traditional aerosol spray cans designed for spraying texture materials. The valve opening is located at the bottom of the assembly rather than at the top, thus allowing highly-viscous materials, such as a fire suppressant material, or materials having large particulates, such as stucco, to be sprayed from an aerosol spray can without clogging of the valves. The valve assembly can spray materials that more closely resemble the original surface texture found on textured and stucco-covered walls and ceilings of buildings and structures.

Description:
FIELD OF INVENTION 
     This application is a Continuation-in-Part of application U.S. Ser. No. 09/312,133 filed on May 14, 1999, now U.S. Pat. No. 6,112,945. This invention relates to a valve assembly for use in an aerosol spray can that is capable of spraying viscous materials or materials with large particulates without clogging or packing like traditional aerosol spray cans designed for spraying texture materials. 
    
    
     BACKGROUND OF THE INVENTION 
     The practice of dispensing heavy and particulate materials through traditional aerosol spray can valve assemblies in the aerosol industry has presented problems in which the heavy and particulate materials to be dispersed clog up the valve assemblies. These heavy and particulate materials may include exterior stucco, heavy sand finishes, drywall and acoustic ceiling patching materials, fire suppressant materials, adhesive and bonding materials, and even culinary sauces. 
     A traditional aerosol spray can may be filled with these heavy and particulate materials for spraying. However, because of the placement of the valve assembly in traditional aerosol spray cans, these heavy and particulate materials will clog up the valve assemblies and render the aerosol spray cans inoperative. Constant operation of these aerosol spray cans in spraying heavy and particulate materials is not possible due to the inconsistent ability of these traditional valve assemblies to dispense these materials without clogging. 
     U.S. Pat. No. 5,715,975, issued to Stem et al., discloses an aerosol spray texturing device that is comprised of a container, a nozzle, a valve assembly, and an outlet. The valve assembly in the &#39;975 patent is located in the upper section of the container near the nozzle. Although the nozzle tube of the device in the &#39;975 patent may be configured to spray texture materials, the device in the &#39;975 patent still has the problem of clogging or packing of the valve assembly by the particulates contained in the texture material for spraying, especially if the particulates are large, like those found in stucco or other heavy and particulate materials such as those mentioned above. 
     U.S. Pat. No. 5,037,011, issued to the present Applicant, discloses a spray apparatus for spraying a texture material through a nozzle. Similarly, in this apparatus, there exists a problem of spraying texture materials having large particulates, such as stucco, because the particulates clog up the valve opening within the spray apparatus. 
     Therefore, a long-standing need has existed to provide an apparatus that may be used to readily apply viscous, heavy and particulate materials in aerosol form, such as exterior stucco, heavy sand finishes, drywall and acoustic ceiling patching materials, fire suppressant materials, adhesive and bonding materials, and culinary sauces. Furthermore, the heavy and particulate materials to be applied should be contained in a hand-held applicator so that the materials may be conveniently stored, as well as dispensed, in a simple and convenient manner without clogging or packing the valve assembly of the applicator. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a valve assembly for use in an aerosol spray can capable of spraying viscous materials or materials with large particulates without clogging or packing like traditional aerosol spray cans designed for spraying texture materials. 
     Another object of the present invention is to provide an inexpensive and economical means for matching surface texture of a repaired or patched surface area on a drywall panel, acoustic ceiling, or stucco-covered surface. 
     Another object of the present invention is to improve the appearance of patched or repaired areas on a textured surface by employing a spray-on hardenable texture material that covers the repaired or patched area and visually assumes the surface texture of the surrounding patched or repaired surface. 
     Another object of the present invention is to provide a hand-held dispensing unit containing a pressurized texture surface material for spray-on and direct application of the material in a liquid or semi-liquid form onto a repaired or patched area so that the surrounding patched or repaired surface will be visually and mechanically matched. 
     Another object of the present invention is to provide a valve assembly for use in an aerosol spray can capable of spraying highly-viscous materials, such as fire suppressant materials, adhesive and bonding materials, and culinary sauces, without clogging or packing like traditional aerosol spray cans when spraying these materials. 
     One embodiment of the valve assembly comprises a dip tube primarily disposed inside a container. A rod is disposed inside the dip tube so that it may move lengthwise within the dip tube. A sealing member is coupled to the bottom end of the rod, so as to form a tight-seal with the bottom opening of the dip tube when the rod is in an up position, and it exposes the bottom opening of the dip tube to the heavy and particulate material inside the container when the rod is in a down position. A bushing is also coupled to the top opening of the dip tube. Finally, an actuator is coupled to the top end of the rod and the bushing, allowing the user to depress on the actuator, thus lowering the rod to its down position and exposing the bottom opening of the dip tube to the material within the container, and allowing the heavy and/or particulate material to move up the dip tube and out of the container. 
     Another embodiment of the valve assembly comprises a dip tube primarily disposed inside the container. An interior tube is disposed inside the dip tube so that it may move lengthwise within the dip tube. There is at least one orifice at the bottom end of the interior tube. A top O-ring is coupled to the interior tube adjacent the at least one orifice to prevent any bypass of the heavy and particulate material into the dip tube, and a bottom O-ring is coupled to the bottom end of the interior tube to seal off the valve assembly when not actuated. The top opening of the dip tube may be coupled to a bushing. Finally, an actuator is coupled to the top end of the interior tube, allowing the user to depress on the actuator, thus lowering the interior tube to its down position and exposing the at least one orifice on the interior tube to the material inside the container and allowing the heavy and particulate material to flow up the interior tube and out of the container. 
     Yet another embodiment of the valve assembly comprises a dip tube primarily disposed inside the container. This dip tube may move lengthwise, and may extend beyond the top of the container. At least a portion of the dip tube rests within a sleeve located inside the container. A spring may engage both the sleeve and the dip tube, thereby having the dual effect of pushing the sleeve against the bottom of the container and the top of the dip tube out of the container. There is at least one orifice on the dip tube that is brought into alignment with an orifice on the sleeve when the dip tube is lowered incident to actuation. There is also at least a first seal coupled to the sleeve adjacent to and below the at least one orifice on the dip tube to form a seal to prevent bypass of the sprayable material into the dip tube when the dip tube is not actuated. There may also be a bushing coupled to the dip tube and adjacent to the top opening. Finally, an actuator is coupled to the top end of the dip tube. This allows the user to depress on the actuator, thus lowering the dip tube to its down position and aligning the at least one orifice on the dip tube with the at least one orifice on the sleeve, thereby allowing the sprayable heavy and particulate material to flow up the dip tube and out of the container. 
     A further embodiment of the valve assembly comprises a dip tube having a predetermined length that is primarily disposed within the container. This dip tube may move lengthwise, and may extend beyond the top of the container. There is also a valve core that is at least partially disposed within the dip tube, with a spring engaging both the valve core and the dip tube. This spring may be a rubber cylinder or a metal spring. The spring pushes the dip tube up and partially out of the container, while pushing the valve core against the bottom of the container. There is at least one orifice on the valve core and at least one orifice on the dip tube that are brought into alignment when the dip tube is lowered. There is also at least one seal located adjacent to and below the orifice on the valve core that prevents sprayable material from entering the dip tube when it is an up position. There may also be a bushing coupled to the dip tube and adjacent to the top opening in the container. This bushing may be a diaphragm that is coupled to the top of the container and the dip tube. Finally, an actuator is coupled to the top end of the dip tube. This allows the user to depress on the actuator, thus lowering the dip tube to its down position and aligning the at least one orifice on the dip tube with the at least one orifice on the valve core, thereby allowing the sprayable heavy and particulate material to flow up the dip tube and out of the container. 
     The above embodiments, and others, may be designed to spray a binary compound. The binary compound can be packaged within one aerosol system, yet kept in two separate portions until combined by the user. Such a configuration is particularly beneficial in the case of a system in which a catalyst is used. In one configuration, the catalyst is stored in the cavity created within a tube that extends into the aerosol system. For example, the catalyst may be stored within the cavity created within the dip tube of one of the above embodiments of the present invention when the interior tube or rod is in an up position. The catalyst may be released to mix with the sprayable material by lowering the rod or interior tube, thereby opening either the bottom of the dip tube or an orifice. The mixing of the two substances may be achieved by providing a storage cap as well as a spray tip. The user may depress the storage cap to lower the rod or interior tube and shake the aerosol system to mix the catalyst with the rest of the sprayable material. Once the two substances have mixed, the user then may replace the storage cap with the spray tip and spray as desired. 
     Alternatively, the catalyst may be stored in a receptacle that is connected to the dip tube inside the container at an orifice on the dip tube. In this configuration, when the interior tube is lowered incident to spraying, the orifice on the receptacle comes into alignment with an orifice on the dip tube. The flow of the catalyst may be controlled by altering the size of the orifice so that an appropriate amount of catalyst is mixed an appropriate amount of sprayable material. This configuration permits the user to control the timing of the mixing of the catalyst with the sprayable material so that the aerosol system may be utilized over a longer period of time. 
     When a heavy or particulate material is dispensed from an aerosol can, the material frequently clogs the spray nozzle or other parts of the apparatus. One reason that this may occur is that, in such materials, the velocity of the fluid and particles is not static. If the diameter or area of the space through which the material is flowing is increased, the velocity of the fluid declines. At the same time, the heavier or denser portions of the material slow down and tend to sink. This results in a partial separation of the material. Conversely, if the diameter or area of the space through which the material flows is decreased, the velocity of the fluid increases. Since it takes additional time for the heavier or denser portions of the material to gain velocity, these portions may aggregate and block the flow of the material. Once the heavier or denser portion starts to aggregate, it can filter heavy or dense portions from the material. This can continue until the backlog of this portion stops the flow of the more liquid portion of the spray. 
     The present invention prevents clogging or packing of the valve assembly because the valve opening is at the bottom of the container, as opposed to being at the top, as in traditional aerosol spray cans. The placement of the value opening at the bottom of the container greatly reduces the clogging or packing of the valve by texture materials having large particulates, since the reduction in cross section occurs much earlier in the spraying system. Further, the diameter of the valve opening may be varied in diameter, depending on the material being sprayed. This improvement allows the efficient and low-cost spraying of heavy and more highly-textured materials, because there is no longer the problem of clogging or packing of the valve opening by the particulates suspended within the texture material. Additionally, the diameter and length of the dip tube may be varied to allow for cosmetic variation in the pattern of the material sprayed. 
     Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings that illustrate, by way of example, various features and embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a valve assembly in accordance with an embodiment of the present invention. 
     FIG. 2 is a cross-sectional view of a valve assembly in accordance with an embodiment of the present invention. 
     FIG. 3 is a perspective view of a valve assembly in accordance with an embodiment of the present invention. 
     FIG. 4 is a cross-sectional view of a valve assembly in accordance with an embodiment of the present invention. 
     FIG. 5 is a perspective view of a valve assembly in a closed position in accordance with an embodiment of the present invention. 
     FIG. 6 is a cross-sectional view of a valve assembly in a closed position in accordance with an embodiment of the present invention. 
     FIGS.  7 ( a ) and  7 ( b ) illustrate perspective views of a valve assembly in accordance with an embodiment of the present invention. 
     FIG. 8 is a cross-sectional view of a valve assembly in an opened position in accordance with an embodiment of the present invention. 
     FIG. 9 is a perspective view of a valve assembly in an opened position in accordance with an embodiment of the present invention. 
     FIG. 10 is a cross-sectional view of a valve assembly in accordance with an embodiment of the present invention. 
     FIG. 11 is a perspective view of a valve assembly in a closed position in accordance with an embodiment of the present invention. 
     FIG. 12 is a perspective view of a valve assembly in an open position in accordance with an embodiment of the present invention. 
     FIG. 13 is a cross-sectional view of a valve assembly in an open position accordance with an embodiment of the present invention. 
     FIG. 14 is a cross-sectional view of a valve assembly in a closed position accordance with an embodiment of the present invention. 
     FIG. 15 is a cross-sectional view of a valve assembly in a closed position accordance with an embodiment of the present invention. 
     FIG. 16 is a cross-sectional view of a valve assembly in an open position accordance with an embodiment of the present invention. 
     FIG. 17 is a cross-sectional view of a valve assembly highlighting a catalyst sack as in a feature of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1 and 3 are perspective views of a valve assembly in accordance with an embodiment of the present invention. A dip tube  1  is coupled to a bushing  4 , which may also be coupled to a cup  5 . An actuator  6  is also coupled to the bushing  4 . 
     In FIGS. 2 and 4, an aperture on the actuator  6  forms a nozzle opening  7 , in which a dispersing apparatus, such as a nozzle cap or a dispensing tube, may be attached or screwed. A rod  2  is primarily disposed inside the dip tube  1  in a way that allows the rod  2  to move within the dip tube  1  along its length. The actuator  6  is coupled to the top end of the rod  2 , so that when the actuator  6  is depressed, the rod  2  moves downward within the dip tube  1 . A sealing member  3  is coupled to the bottom end of the rod  2 , so that when the rod  2  is in an up position, i.e., the actuator  6  is not depressed, the sealing member  3  forms a tight-seal with the bottom opening of the dip tube  1 . However, when the rod  2  is in a down position, i.e., the actuator  6  is depressed, the sealing member  3  exposes the bottom opening of the dip tube  1  to the heavy and particulate material inside the container, and the propellant within the container will force the texture material through the bottom opening of the dip tube  1 , up through the dip tube  1 , and out of the container through the nozzle opening  7 . The rod and the sealing member may be one unitary piece. The heavy and particulate material may be a variety of sprayable materials, including viscous materials or materials having large particulates, like that of stucco. 
     The cup  5  acts as a guide to limit how far down the actuator  6  may be depressed, and in turn how far down the rod  2  may travel within the dip tube  1 . If the actuator  6  is depressed too far, the bottom end of the rod  2  may come in contact with the bottom surface of the container, which may result in damage to the container. The cup  5  is also adapted to fit securely over the top portion of an aerosol spray can and may also provide a surface for attaching the valve assembly to the aerosol spray can. 
     The placement of the valve opening at the bottom of the container, as opposed to near the top of the container, as described in the prior references, drastically reduces the clogging and packing of the valve opening as experienced by traditional aerosol spray cans when spraying texture materials containing large particulates, such as stucco. Further descriptions of an example of a heavy and particulate material is disclosed in pending patent application (Ser. No. 09/312,554) entitled, “Hardenable Texture Material in Aerosol Form,” incorporated herein by reference. In addition to being capable of spraying stucco-like materials, the valve assembly is also particularly useful in spraying other types of materials having large particulates or high viscosities, including fire suppressant materials. These materials having large particulates or high viscosities may be dispensed directly from the valve system of an aerosol dispensing container. The aerosol dispensing container is preferably a size that allows it to be hand held and may be operated with one hand. 
     Ideally, the actuator  6  is made out of an elastic material, such as rubber, so as to allow the retention of the rod  2  in the up position when the actuator  6  is not depressed. The actuator  6  may also be made of a non-elastic material, but there may be a spring member coupled to the bushing  4  and engaging the actuator  6  so as to spring-load the actuator  6 . The sealing member  3  should be made of a material, such as rubber, that will allow the sealing member  3  to form a tight-seal with the bottom opening of the dip tube  1  so as to prevent any entry of the texture material and the aerosol carrier into the dip tube  1  when the rod  2  is in the up position, i.e., when the actuator  6  is not being depressed. 
     FIGS. 5 to  9  show another embodiment of the present invention. A dip tube  1  is coupled to a bushing  4 , which may also be coupled to a cup  5 . A spring member  9  may be coupled to the bushing  4  to spring-load the actuator  6  engaging the spring member  9  on the bushing  4 . 
     An interior tube  10  with a top end and a bottom end is disposed inside the dip tube  1  in a way that allows the interior tube  10  to move within the dip tube  1  along its length. The actuator  6  is coupled to the top end of the interior tube  10 , so that when the actuator  6  is depressed, the interior tube  10  moves downward within the dip tube  1 . There is at least one orifice  13  at the bottom end of the interior tube  10  so as to allow the heavy and particulate material from inside the container to flow up through the interior tube  10  and out of the nozzle opening. A top O-ring  11  is coupled to the interior tube  10  adjacent to and just above the at least one orifice  13  so as to form a seal to prevent any bypass of the heavy and particulate material from the container into the dip tube  1  when the interior tube  10  is in a down position. A bottom O-ring  12  is coupled to the bottom end of the interior tube  10  so as to seal off and close the valve assembly when the interior tube  10  is in an up position. 
     As described above, the cup  5  may act as a guide so as to limit how far down the actuator  6  may be depressed, as well as provide a surface for attaching the valve assembly to the container. 
     FIG. 10 shows yet another embodiment of the present invention. There is at least one exterior orifice  14  on the dip tube  1  that is adapted to be in flow alignment with the at least one orifice  13  of the interior tube  10 . Therefore, when the actuator  6  is depressed and the interior tube  10  is lowered to its open position, the at least one orifice  13  of the interior tube  10  aligns with the at least one orifice  14  on the dip tube  1  so that the material inside the container may flow through the exterior orifice  14  and into the at least one orifice  13  of the interior tube  10  and up through the interior tube  10  and out of the container through the nozzle opening  7 . Similarly, there is a top O-ring  11  and a bottom O-ring  12 , as described above, for sealing off the dip tube  1  to prevent any bypass of the heavy and particulate material from the container and for closing the valve assembly. 
     FIGS. 11-14 depict another embodiment of the present invention. FIGS. 11 and 14 depict the assembly with the dip tube  1  in an up position. FIGS. 12 and 13 depict the assembly with the dip tube  1  in a down position. There is at least one exterior orifice  14  on dip tube  1  that is adapted to be in flow alignment with the at least one orifice  17  of the sleeve  15 . Therefore, when the actuator (not shown) is depressed, and dip tube  1  is lowered to its open position, the at least one orifice  13  of the dip tube aligns with the at least one orifice  17  on the sleeve  15  so that the material inside the container may flow through the orifice  14  of the dip tube  1  and up through the dip tube  1  and out of the container through the nozzle (not shown). Similarly, there is a top seal  11  and a bottom seal  12 , as described above, for sealing off the dip tube  1  to prevent any bypass of the heavy and particulate material from the container and for closing the valve assembly. These seals may be O-rings. 
     FIGS. 15 and 16 depict another embodiment of the present invention. There is at least one exterior orifice  14  on dip tube  1  that is adapted to be brought into flow alignment with the at least one orifice  21  on valve core  18  when dip tube  1  is lowered. A spring  19  may engage both the dip tube  1  and the valve core  18  such that the dip tube  1  is pushed upwards, out of the container, and the valve core  18  is pushed downwards, towards the bottom of the container. Spring  19  may, for example, be a rubber cylinder or a metal spring. There is at least one seal  22  located adjacent to and below orifice  21  on valve core  18  that prevents sprayable material and propellant from entering the dip tube and the valve core when it is an up position. There is at least a second seal  23  on the interior of dip tube  1  located adjacent to and above orifice  14  that prevents sprayable material from entering dip tube  1  when it is an up position. Further, there is at least a third seal  24  on the interior of dip tube  1  located adjacent to and below orifice  14  that prevents sprayable material from entering dip tube  1  and valve core  18  when dip tube  1  is in an up position. There may also be a bushing  4  coupled to dip tube  1  and adjacent to the top of the container. This bushing  4  may be a diaphragm that is coupled to the top of the container and dip tube  1 . A cup may also be included, as discussed above. Finally, an actuator (not shown) may be coupled to the top end of the dip tube. 
     FIGS. 15-16 also depict another feature of the present invention that may be utilized in conjunction with embodiments of the present invention, such as described above: the storage of a binary system within one system such that the two portions are kept separate until caused to combine by the user. Such a configuration is particularly beneficial in the case of a system requiring a catalyst. A catalyst may be stored within the cavity  26  located within the dip tube  1  when the interior rod  2  is in an up position. Alternatively, the catalyst may be stored within the cavity  26  located within interior tube  10 . When the interior rod  2  or interior tube  10  is lowered by the user, the catalyst may then mix with the sprayable heavy and particulate material. The user may shake the can while the interior rod  2  or interior tube  10  is lowered to facilitate mixing the catalyst  25  with the heavy and particulate material. This may be accomplished by providing both a cap and a spray nozzle. The user may first depress the cap to lower the interior rod or interior tube to mix the catalyst with the sprayable material. Secondly, the user may replace the cap with the spray nozzle and spray the material as desired. 
     As shown in FIG. 17, the catalyst may also be stored in a pouch  30  that is connected to the dip tube  31  inside the container at an orifice  32  on the dip tube  31 . In this configuration, when the interior tube  33  is lowered incident to spraying, an orifice  32  on the dip tube  31  comes into alignment with another orifice  34  on the interior tube  33 , thus dispensing a portion of the catalyst at the same time as a portion of the sprayable heavy and particulate material is dispensed. The amount of catalyst that is dispensed with the sprayable heavy and particulate material may be varied by changing the size of one or both of the orifices  32 ,  34 . 
     While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. 
     The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.