Aerosol valve with defined flow paths

Abstract

An aerosol valve having a valve stem, valve stem housing, compression spring, and a hard stop formed by the interaction of valve stem and valve stem housing is provided. The hard stop prevents the compression spring from becoming fully compressed, or coil-bound, when the valve stem is pressed to dispense a product formulation from the container, thereby creating open spaces between coils of the compression spring and providing a defined flow path for the product formulation. The aerosol valve increases mixing and turbulence of the product formulation that reduce agglomerations of solids that might otherwise block the flow paths. The additional defined flow path also directs more of the product to the valve stem aperture, further increasing dispensing of the product formulation from the container. A method of using the aerosol valve is provided.

What is claimed is: 
     
         1 . An aerosol valve for dispensing a product formulation from a container, comprising:
 a mounting cup on the container for orientating the aerosol valve on the container;   a seal positioned on the mounting cup;   a valve stem housing positioned below the mounting cup and adjacent the seal, the valve stem housing having an interior surface;   a dip tube positioned below the valve stem housing, the dip tube being connected to a reservoir of the product formulation in the container;   a valve stem in the valve stem housing, the valve stem having a top portion that protrudes through and above the seal and a bottom portion in the valve stem housing, the valve stem further comprising a valve stem aperture and a center hole; and   a compression spring positioned in the valve stem housing contacting the valve stem, the compression spring comprising:
 a spring coil that, in a first position, forms a plurality of spaces with each space between adjacent spring coils; and 
 a center space circumscribed by the spring coil with a center space diameter, 
   wherein the valve stem is movable from a top position when the aerosol valve is in an unactuated, closed position, to a bottom position when the aerosol valve is fully actuated,   wherein the interior surface interacts with the valve stem to form a hard stop that prevents the downward-moving valve stem from fully compressing the spring coils when the aerosol valve is fully-actuated,   wherein when the aerosol valve is actuated, the product formulation in the reservoir flows upwardly under pressure through the dip tube, with a first portion of the product formulation flowing into and through the center space of the compression spring, around the outside of the valve stem body, enters the valve stem aperture, and into the center hole to dispense the product formulation from the container, forming a first flow path, and a second portion of the product formulation flowing into and through the spring coils and the spaces therebetween, forming a second flow path.   
     
     
         2 . The aerosol valve according to  claim 1 , wherein the interaction of the product formulation with the spring coils in the second flow path increases mixing of the product formulation and breaks up agglomerations of solids in the product formulation. 
     
     
         3 . The aerosol valve according to  claim 1 , wherein the increased mixing of the product formulation and breaking up of agglomerations of solids in the second flow path reduces the incidence of blockages and thereby decreases a product failure rate of the aerosol valve. 
     
     
         4 . The aerosol valve according to  claim 1 , wherein the valve stem housing further comprises:
 an interior surface having an area that inclines inward to form the hard stop that is a physical barrier to further downward movement of the valve stem.   
     
     
         5 . The aerosol valve according to  claim 4 , wherein the position of the hard stop allows the valve stem to attain the bottom position that partially, but not completely, compresses the spring coils of the compression spring. 
     
     
         6 . The aerosol valve according to  claim 1 , wherein the first flow path is a short path that has few abrupt changes in flow direction to decrease resistance and back pressure of the product formulation as it flows through the aerosol valve. 
     
     
         7 . The aerosol valve according to  claim 1 , wherein the first flow path has few loci at which the product formulation can agglomerate and impede the flow of the product formulation. 
     
     
         8 . The aerosol valve according to  claim 1 , wherein the flow of the product formulation through the spring coils and in the spaces therebetween increases turbulence of the product formulation to maintain a small average particle size for the solids therein. 
     
     
         9 . The aerosol valve according to  claim 1 , wherein the spring coils and the spaces therebetween direct the product formulation to flow into and upward through the center space of the compression spring, so that the product formulation exits as a cascade through an upper end of the compression spring where it enters the valve stem aperture and flows into the center hole,
 thereby increasing the amount of the product formulation entering into the valve stem aperture and center hole.   
     
     
         10 . The aerosol valve according to  claim 1 , wherein the first flow path and the second flow path form a single flow path before entering the valve stem aperture. 
     
     
         11 . The aerosol valve according to  claim 1 , wherein all, or substantially all, of the product formulation flows in and through the spaces between the spring coils of the compression spring before entering the valve stem aperture. 
     
     
         12 . The aerosol valve according to  claim 1 , wherein bottom portion of the valve stem is shaped to form a flow passageway through which the product formulation flows when the aerosol valve is actuated. 
     
     
         13 . The aerosol valve according to  claim 1 , wherein the product formulation comprises a mixture of a chemical composition and a propellant. 
     
     
         14 . The aerosol valve according to  claim 13 , wherein the chemical composition comprises a powder. 
     
     
         15 . The aerosol valve according to  claim 14 , wherein the product formulation is a high-solids product formulation. 
     
     
         16 . An aerosol valve for dispensing a product formulation from a container, comprising:
 a mounting cup on a top portion of the container that orientates the aerosol valve in a position perpendicular to the mounting cup;   a seal positioned on the mounting cup;   a valve stem housing positioned below the mounting cup and adjacent the seal, the valve stem having an interior surface;   a dip tube positioned below the valve stem housing, the dip tube being connected to a reservoir of the product formulation in the container;   a valve stem being in the valve stem housing, the valve stem having a top portion that protrudes through and above the seal and a bottom portion in the valve stem housing, the valve stem further comprising a valve stem aperture and a center hole; and   a compression spring positioned in the valve stem housing and contacting the valve stem, the compression spring comprising:
 a spring coil that, in a first position, forms a plurality of spaces with each space between adjacent spring coils; and 
 a center space circumscribed by the spring coil with a center space diameter, 
   wherein the valve stem is in a vertical position prior to actuation, and is tilted away from the vertical position by pressing sideways on the valve stem to form a tilted valve stem that can actuate the aerosol valve,   wherein the interior surface has an area that inclines inward and interacts with the tilted valve stem to form a hard stop so that the tilted valve stem partially, but not completely, compresses the spring coil when the aerosol valve is actuated,   wherein when the aerosol valve is actuated, the product formulation in the reservoir flows upwardly under pressure through the dip tube,   wherein the product formulation has a first portion that flows into and through the center space of the compression spring, is deflected around the outside of the valve stem body, enters the valve stem aperture, and flows into the center hole to dispense the product formulation from the container, forming a first flow path,   wherein the product formulation has a second portion that flows into and through the spring coils and the spaces therebetween, forming a second flow path,   wherein the interaction of the product formulation with the spring coils of the second flow path increases mixing of the product formulation and breaks up agglomerations of solids in the product formulation.   
     
     
         17 . The aerosol valve according to  claim 16 , wherein the increased mixing of the product formulation and breaking up of agglomerations of solids in the second flow path reduce the incidence of blockages to decrease a product failure rate of the aerosol valve. 
     
     
         18 . The aerosol valve according to  claim 16 , wherein the valve stem is tilted between about 5% and about 10% from the vertical position to actuate the aerosol valve. 
     
     
         19 . A method for using an aerosol valve for dispensing a product formulation from a container, comprising:
 actuating the aerosol valve to dispense the product formulation, wherein the aerosol valve comprises:
 a mounting cup on the container that orientates the aerosol valve on the container; 
 a seal positioned on the mounting cup; 
 a valve stem housing positioned below the mounting cup and adjacent the seal, the valve stem having an interior surface; 
 a dip tube positioned below the valve stem housing, the dip tube being connected to a reservoir of the product formulation in the container; 
 a valve stem positioned in the valve stem housing, the valve stem having a top portion that protrudes through and above the seal and a bottom portion in the valve stem housing, the valve stem having a valve stem aperture and a center hole; and 
 a compression spring positioned in the valve stem housing and contacting the valve stem, the compression spring comprising:
 a spring coil that, in a first position, forms a plurality of spaces with each space between adjacent spring coils; and 
 a center space circumscribed by the spring coil with a center space diameter, 
 
 wherein the valve stem is movable from a top position when the aerosol valve is in an unactuated, closed position, to a bottom position when the aerosol valve is actuated, 
 wherein the interior surface has an area that interacts with the valve stem to form a hard stop that prevents the valve stem from fully compressing the spring coils when the aerosol valve is actuated, 
 wherein when the aerosol valve is actuated, the product formulation in the reservoir flows upwardly under pressure through the dip tube, 
 wherein the product formulation has a first portion that flows into and through the center space of the compression spring, is deflected around the outside of the valve stem body, enters the valve stem aperture, and flows into the center hole to dispense the product formulation from the container, forming a first flow path, 
 wherein the product formulation has a second portion that flows into and through the spring coils and the spaces therebetween, forming a second flow path, and 
 wherein the interaction of the product formulation with the spring coils on the second flow path increases mixing of the product formulation and breaks up agglomerations of solids in the product formulation, and 
   releasing the valve stem to stop dispensing the product formulation.   
     
     
         20 . The method according to  claim 19 , wherein the increased mixing of the product formulation and breaking up of agglomerations of solids in the second flow path reduces the incidence of blockages and thereby decreases a product failure rate of the aerosol valve.