Multi-piece valve stem for aerosols

FIELD OF THE INVENTION

0001The present invention relates to multi-piece valve stems for valves for aerosol dispensers, and to valves and aerosol dispensers having such a multi-piece valve stem.

BACKGROUND OF THE INVENTION

0002Aerosol dispensers are well known in the art. Aerosol dispensers typically comprise an outer container which acts as a frame for the remaining components and as a pressure vessel for propellant and product contained therein. Outer containers made of metal are well known in the art. However, metal containers can be undesirable due to high cost and limited recyclability. Attempts to use plastic have occurred in the art. Relevant attempts in the art to employ plastic in aerosol dispensers are found in <patcit id="pcit0001" dnum="US2863699A"><text>US patents 2,863,699</text></patcit>; <patcit id="pcit0002" dnum="US3333743A"><text>3,333,743</text></patcit>; <patcit id="pcit0003" dnum="US9296550B"><text>9,296,550</text></patcit>; <patcit id="pcit0004" dnum="US9334103B"><text>9,334,103</text></patcit> and <patcit id="pcit0005" dnum="US20090014679B"><text>2009/0014679</text></patcit>.

0003The outer containers are typically, but not necessarily, cylindrical. The outer container may comprise a closed end bottom adjoining the sidewalls and for resting on horizontal surfaces such as shelves, countertops, tables etc. The bottom of the outer container may comprise a re-entrant portion as shown in <patcit id="pcit0006" dnum="US3403804A"><text>US patent 3,403,804</text></patcit> or base cup as shown in <patcit id="pcit0007" dnum="US9061795B"><text>US patent 9,061,795</text></patcit>. Sidewalls defining the shape of the outer container extend upwardly from the bottom to an open top.

0004The open top defines a neck for receiving additional components of the aerosol dispenser. The industry has generally settled upon a nominal neck diameter of 2.54 cm, for standardization of components among various manufacturers, although smaller diameters, such as 20 mm, are also used. Various neck shapes are shown in <patcit id="pcit0008" dnum="US6019252A"><text>US patents 6,019,252</text></patcit>; <patcit id="pcit0009" dnum="US7028866B"><text>7,028,866</text></patcit>; <patcit id="pcit0010" dnum="US7279207B"><text>7,279,207</text></patcit> and <patcit id="pcit0011" dnum="US7303087B"><text>7,303,087</text></patcit>.

0005Typically a valve cup is inserted into the neck. The valve cup is sealed against a crimp ring at the top of the neck to prevent the escape of the propellant and loss of pressurization, such as described in <patcit id="pcit0012" dnum="US8074847B"><text>US Patents 8,074,847</text></patcit>; <patcit id="pcit0013" dnum="US8096327B"><text>8,096,327</text></patcit>; <patcit id="pcit0014" dnum="US8844765B"><text>8,844,765</text></patcit> and <patcit id="pcit0015" dnum="US8869842B"><text>8,869,842</text></patcit>. The valve cup holds the valve components which are movable in relationship to the balance of the aerosol dispenser. Suitable valves are shown in commonly assigned <patcit id="pcit0016" dnum="US8511522B"><text>US patents 8,511,522</text></patcit> and <patcit id="pcit0017" dnum="US9132955B"><text>9,132,955</text></patcit>. When the valves are opened, product may be dispensed through a nozzle, etc. as described in commonly assigned <patcit id="pcit0018" dnum="US9174229B"><text>US patents 9,174,229</text></patcit>.

0006A bag may be used to contain product for selective dispensing by a user. Dispensing of product from the bag occurs in response to the user actuating the valve. The bag separates product within the bag from propellant disposed between the bag and container. This bag limits or even prevents intermixing of the contents of the bag and the components outside of the bag. Thus, product may be contained in the bag. Propellant may be disposed between the outside of the bag and the inside of the outer container. Upon actuation of the valve, a flow path out of the bag is created. This embodiment is commonly called a bag in can and may be used, for example, in dispensing shaving cream gels. Alternatively, a bag may be directly joined to the valve housing, in a configuration commonly called a bag on valve. A suitable bag configuration is disclosed in commonly assigned application, P&amp;G Case 14458, serial no. 15/235,227, filed August 12, 2016 which teaches attaching a bag to a valve cup.

0007If a bag configuration is desired, propellant may be disposed between the bag and outer container, as disclosed in commonly assigned <patcit id="pcit0019" dnum="US8631632B"><text>US patents 8,631,632</text></patcit> and <patcit id="pcit0020" dnum="US8869842B"><text>8,869,842</text></patcit>. Afterwards, product fill may occur in a separate, remote, operation, optionally carried out in another location, which may be in the same country or in a different country. Such a manufacturing process can conserve costs in production, shipment and/or storage.

0008An aerosol container having a bag therein may be made from a dual layer preform, having plural layers disposed one inside the other. Relevant attempts include <patcit id="pcit0021" dnum="US3450254A"><text>US patents 3,450,254</text></patcit>; <patcit id="pcit0022" dnum="US4330066A"><text>4,330,066</text></patcit>; <patcit id="pcit0023" dnum="US6254820B"><text>6,254,820</text></patcit>; <patcit id="pcit0024" dnum="USRE30093E"><text>RE 30093 E</text></patcit>; and publications <patcit id="pcit0025" dnum="WO9108099A"><text>WO 9108099</text></patcit> and <patcit id="pcit0026" dnum="US20110248035A1"><text>US 2011/0248035 A1</text></patcit>. But each of these attempts requires a separate operation to attach the bag to the relevant component. Each attachment step takes time in manufacturing and creates the opportunity for leakage if not correctly performed. Improvements in dual layer preforms are found in commonly assigned application P&amp;G Case 14461, Application no. 15/235,279, filed August 12, 2016.

0009Alternatively, a dip tub may be used if intermixing of the product and propellant is desired. When the user actuates the valve, the product and propellant are dispensed together through the dip tube. One configuration is shown in commonly assigned <patcit id="pcit0027" dnum="US6039222A"><text>US patent 6,039,222</text></patcit>. This embodiment may utilize a dip tube. The dip tube takes the product and propellant mixture from the bottom of the outer container. Or a piston may be used to expel product, if it is particularly viscous, as described in commonly assigned <patcit id="pcit0028" dnum="US20160368633A"><text>US publication 2016/0368633</text></patcit>.

0010If a valve is to be assembled into an aerosol, typically the valve cup is crimped onto the neck of the aerosol container. But this operation is expensive and is difficult to perform with a plastic valve cup. A separate interlock may be used to attach a valve to a valve cup, particularly a plastic valve and plastic valve cup are used. Suitable interlocks include bayonet fittings and threads as disclosed in commonly assigned P&amp;G application, Case 14458, serial no. 15/235,237, filed August 12, 2016.

0011The valve may be inserted into the valve cup for selective actuation by the user. The valve is typically normally closed, but may be opened to create a flow path for the product to ambient or a target surface. The valve typically has a valve stem with a head disposed in the product chamber. The head seats against a valve seal to prevent loss of product, until dispensing is desired. A sample valve is disclosed in <patcit id="pcit0029" dnum="US2812884A"><text>US 2812884 A</text></patcit>.

0012The valve may be compatible with local recycling standards. Aerosol valves are disclosed in commonly assigned <patcit id="pcit0030" dnum="US8511522B"><text>US patents 8,511,522</text></patcit>, <patcit id="pcit0031" dnum="US9132955B"><text>9,132,955</text></patcit> and <patcit id="pcit0032" dnum="US9758295B"><text>9,758,295</text></patcit>. The aerosol valve has a valve stem which moves in response to user actuation, to seat and unseat a valve stem head from a seal.

0013The valve stem head is enlarged relative to the head, to closingly seat against a hole through the seal.

0014The valve stem has a disc, to limit travel upon actuation. The disc is also enlarged relative to the stem, to engage the top of the seal or valve housing at the end of stem travel. Typically the head diameter is smaller than the disc diameter.

0015The valve stem is typically inserted through the seal hole by pushing the head therethough. The seal is resilient, to allow the head of the valve stem to pass therethrough. But if the head is too large, it cannot pass through the hole in the valve seal. If the head is too small, inadequate sealing and even ejection of the stem may result.

0016Accordingly, it is an object of this invention to decouple the size of the valve stem head from the assembly problems which occur if the head is too large relative to the hole through the valve seal.

SUMMARY OF THE INVENTION

0017The invention comprises a valve for selectively releasing a product from an aerosol dispenser according to claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

0018<ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001 f0002 f0003 f0004 f0005">Figures 1 - 4J</figref> are drawn to scale.</li><li><figref idref="f0001">Figure 1</figref> is a side elevational view of an aerosol dispenser according to the present invention.</li><li><figref idref="f0002">Figure 2A</figref> is a side elevational sectional view of an aerosol dispenser having a collapsible bag.</li><li><figref idref="f0003">Figure 2B</figref> is a side elevational sectional view an aerosol dispenser having a dip tube.</li><li><figref idref="f0004">Figure 3A</figref> is a vertical sectional view of a valve that is not according to the claims and that has a disc joined to the upper stem portion.</li><li><figref idref="f0004">Figure 3B</figref> is a perspective sectional view of the valve of <figref idref="f0004">Figure 3A</figref>.</li><li><figref idref="f0004">Figure 3C</figref> is an exploded sectional perspective view of the valve of <figref idref="f0004">Figure 3A</figref>.</li><li><figref idref="f0004">Figure 3D</figref> is an exploded sectional perspective view of the valve of <figref idref="f0004">Figure 3B</figref>.</li><li><figref idref="f0004">Figure 3E</figref> is a vertical sectional view of a valve of the seal and valve stem of <figref idref="f0004">Figure 3A</figref>.</li><li><figref idref="f0004">Figure 3F</figref> is a perspective sectional view of the seal and valve stem of <figref idref="f0004">Figure 3E</figref>.</li><li><figref idref="f0004">Figure 3G</figref> is an exploded sectional perspective view of the seal and valve stem of <figref idref="f0004">Figure 3E</figref>.</li><li><figref idref="f0004">Figure 3H</figref> is an exploded sectional perspective view of the seal and valve stem of <figref idref="f0004">Figure 3F</figref>.</li><li><figref idref="f0004">Figure 3I</figref> is a perspective view of a valve stem according to <figref idref="f0004">Figure 3A</figref>.</li><li><figref idref="f0004">Figure 3J</figref> is an exploded perspective view of the valve stem of <figref idref="f0004">Figure 3I</figref>.</li><li><figref idref="f0005">Figure 4A</figref> is a vertical sectional view of a valve embodiment according to the claims and having an upper stem portion</li><li>joined to the lower stem portion.</li><li><figref idref="f0005">Figure 4B</figref> is a perspective sectional view of the valve of <figref idref="f0005">Figure 4A</figref>.</li><li><figref idref="f0005">Figure 4C</figref> is an exploded sectional perspective view of the valve of <figref idref="f0005">Figure 4A</figref>.</li><li><figref idref="f0005">Figure 4D</figref> is an exploded sectional perspective view of the valve of <figref idref="f0005">Figure 4B</figref>.</li><li><figref idref="f0005">Figure 4E</figref> is a vertical sectional view of a valve of the seal and valve stem of <figref idref="f0005">Figure 4A</figref>.</li><li><figref idref="f0005">Figure 4F</figref> is a perspective sectional view of the seal and valve stem of <figref idref="f0005">Figure 4E</figref>.</li><li><figref idref="f0005">Figure 4G</figref> is an exploded sectional perspective view of the seal and valve stem of <figref idref="f0005">Figure 4E</figref>.</li><li><figref idref="f0005">Figure 4H</figref> is an exploded sectional perspective view of the seal and valve stem of <figref idref="f0005">Figure 4F</figref>.</li><li><figref idref="f0005">Figure 4I</figref> is a perspective view of a valve stem according to the embodiment.</li><li><figref idref="f0005">Figure 4J</figref> is an exploded perspective view of the valve stem of <figref idref="f0005">Figure 4I</figref>.</li><li><figref idref="f0006">Figure 5</figref> is a schematic exploded side elevational view of a valve stem that is not according to the claims and having three separate components and threaded fittings, the disc and lower stem portion being shown in cutaway to reveal internal threads.</li><li><figref idref="f0006">Figure 6</figref> is a schematic top plan view of an alternative disc that is not according to the claims and having radially extending fingers.</li></ul>

DETAILED DESCRIPTION OF THE INVENTION

0019Referring to <figref idref="f0001">Fig. 1</figref>, an aerosol dispenser 20 is shown. The aerosol dispenser 20 comprises a pressurizeable outer container 22 usable for such a dispenser. The outer container 22 may comprise plastic or metal, as are known in the art. The outer container 22 has both product 42 and propellant 40 disposed therein at the point of use.

0020The outer container 22 has an opening with a valve cup 26 therein. A user activated dispensing valve 28 may be disposed in the valve cup 26. A product delivery device may be joined to the valve cup 26. Propellant 40 may be disposed between the outer container 22 and the product delivery device. The product 42 and propellant 40 may be separately dispensed or may be dispensed together.

0021The aerosol dispensers 20, and components thereof, may have a longitudinal axis LA, and may optionally be axi-symmetric with a round cross section. Alternatively, the outer container 22, a product delivery device therein, a dispensing valve 28, etc., may be eccentric and have a square, elliptical or other cross section.

0022The outer container 22 may have an opening. The opening is typically at the top of the pressurizeable container 22 when the pressurizeable container 22 is in its-in use position. The opening defines a neck 24, to which other components may be sealed.

0023The valve cup 26 may be integral and formed from a single piece of metal comprising plural contiguous and annular walls. Alternatively, the valve cup 26 may comprise plastic, or any material suitable for forming around or welding to the neck 24. The valve cup 26 may have a valve cup hole, to allow for a valve stem to longitudinally move therethrough.

0024A dispensing valve 28, in turn, may be disposed within or otherwise joined to the valve cup 26. The dispensing valve 28 provides for retention of product 42 within the aerosol dispenser 20 until the product 42 is selectively dispensed by a user. The product 42 may be dispensed through a dip tube 56 or from a bag 55, as is known in the art.

0025The dispensing valve 28 may be selectively actuated by an actuator 25. A suitable subcombination may comprise the outer container 22, valve cup 26, dispensing valve 28, and any propellant 40 therein. The outer container 22, and valve 28 according to the present invention may be entirely polymeric and particularly entirely Stream 1 as defined by the Society of Plastics Engineers.

0026Selective actuation of the dispensing valve 28 allows the user to dispense a desired quantity of the product 42 on demand. Illustrative and nonlimiting products 42 for use with the present invention may include shave cream, shave foam, body sprays, body washes, perfumes, cleansers, air fresheners, astringents, foods, paints, etc.

0027Referring to <figref idref="f0002">Figs. 2A</figref> and <figref idref="f0003">2B</figref>, inside the outer container 22 may be a product delivery device. The product delivery device may comprise a collapsible bag 55 as shown in <figref idref="f0002">Figure 2A</figref>. The collapsible bag 55 may be mounted in sealing relationship to the neck 24 of the container and/or to the dispensing valve 28. This arrangement is known in the art as a bag-on-valve. The collapsible bag 55 may hold product 42 therein, and prevent intermixing of such product 42 with propellant 40. The propellant 40 may be stored outside the collapsible bag 55, and inside the outer container 22.

0028The collapsible bag 55 may expand upon being charged with product 42. Such expansion decreases the available volume inside the outer container 22. Decreasing the available volume increases the pressure of any propellant 40 therein according to Boyles law.

0029The product delivery device may alternatively or additionally comprise a dip tube 56 as shown in <figref idref="f0003">Figure 2B</figref>. The dip tube 56 extends from a proximal end sealed to the dispensing valve 28. The dip tube 56 may terminate at a distal end juxtaposed with the bottom of the outer container 22. This embodiment provides for intermixing of the product 42 and propellant 40. Both are co-dispensed in response to selective actuation of the dispensing valve 28 by a user. Again, insertion of product 42 and/or propellant 40 into the outer container 22 increases pressure therein according to Boyles law.

0030The outer container 22 may comprise a plastic pressurizeable container. The plastic may be polymeric, and particularly comprise PET. The dispensing valve 28, and optional valve cup 26 may be welded to the neck 24 of the outer container 22, as discussed below. The valve cup 26 may be clinched to the neck 24 in known fashion.

0031The pressurizeable container may further include a propellant 40. The propellant 40 may be disposed between the outer container 22 and the product delivery device. Alternatively propellant 40 may be disposed in the outer container 22 and/or the collapsible bag 55. Typically the pressure in the outer container 22 is greater than the pressure in the collapsible bag 55, so that product 42 may be dispensed from within the bag. If a dip tube 56 is selected for the product delivery device, the propellant 40 and product 42 may be intermixed, and thus co-dispensed. The pressure of the propellant 40 within the outer container 22 provides for dispensing of the product 42/co-dispensing of product 42/propellant 40 to ambient, and optionally to a target surface. The target surface may include a surface to be cleaned or otherwise treated by the product 42, skin, etc. Such dispensing occurs in response to the user actuating the dispensing valve 28.

0032Examining the components in more detail, the product delivery device may comprise a flexible, collapsible bag 55. The pressure boundary for the propellant 40 is formed, in part, by the collapsible bag 55. Or the product delivery device may comprise a dip tube 56. In either embodiment, the pressure boundary for the propellant 40 is formed, in part by the underside of the dispensing valve 28 when the valve 28 is closed.

0033If desired, the outer container 22, dispensing valve 28, dip tube 56 and/or collapsible bag 55 may be polymeric. By polymeric it is meant that the component is formed of a material which is plastic, comprises polymers, and/or particularly polyolefin, polyester or nylons. Thus, the entire aerosol dispenser 20 or, specific components thereof, may be free of metal, allowing exposure to microwave energy.

0034The outer container 22 may define a longitudinal axis LA of the aerosol dispenser 20. The outer container 22 may be axisymmetric as shown, or, may be eccentric. While a round cross-section is shown, the invention is not so limited. The cross-section may be square, elliptical, irregular, etc. Furthermore, the cross section may be generally constant as shown, or may be variable. If a variable cross-section is selected, the outer container 22 may be barrel shaped, hourglass shaped, or monotonically tapered.

0035The outer container 22, and all other components, except the TPE gasket 24G, and valve cup 26 may comprise, consist essentially of or consist of PET, PEN, Nylon EVOH or blends thereof to meet DOT SP 14223. Such materials may be selected from a single class of recyclable materials, as set forth above by the SP1.

0036Recycling class 1 thermoplastic elastomer [TPE] may be selected for the gasket 24G. The TPE material may be selected to be resistant to the propellant 40 and/or product 42 desired for use. A hydrophilic TPE-E based compound formulated to provide adhesion to PET and chemical resistance to silicone oil may be used as one or more components in the aerosol dispenser 20. Class 1 TPE material sold by Kraiburg TPE GmbH &amp; Co KG of Waldkraiburg, Germany under the name Hcc8791-52 may be suitable.

0037The neck 24 may be connected to the container sidewall by a shoulder 23. The shoulder 23 may more particularly be joined to the sidewall by a radius. The shoulder 23 may have an annular flat. The neck 24 may have a greater thickness at the top of the outer container 22 than at lower portions of the neck 24 to provide a differential thickness. Such differential thickness may be accomplished through having an internally stepped neck 24 thickness.

0038Referring to <figref idref="f0004 f0005">Figs. 3A - 4J</figref> and examining the valve 28 in more detail, the valve has a housing 27 which is stationary relative to the outer container 22 and provides a frame for the other components of the valve 28. The housing 27 has a housing hole therethrough to accommodate a valve stem 31. The housing hole has an associated housing hole diameter.

0039A seal 29 is joined to the housing 27. The seal 29 provides for closure of the valve 28 when product 42 is not being dispensed. The seal 29 has a seal hole therethrough with an associated seal hole diameter. The seal hole 29 is preferably concentric with the housing hole. The seal hole diameter is adapted to fit the diameter of the portion of the valve stem 31 slidably moving therethrough. The valve stem 31 moves, preferably by longitudinal translation, to allow dispensing to occur upon actuation. Alternatively, the stem 31 may articulate about the seal 29, as occurs in a tilt valve 28.

0040The stem 31 has an upper stem portion 31U joined to or fitted to a lower stem portion 31L. The upper stem portion 31U has an upper stem portion diameter. The lower stem portion 31L has a lower stem portion diameter. The lower stem portion 31L and upper stem portion 31U diameters are taken at the interface thereof. The lower stem portion 31L has a valve stem head 33 proximate the distal end thereof. The valve stem head 33 has a stem diameter which is larger than the lower stem portion diameter. The valve stem head 33 sealingly and closingly fits against the seal 29 disposed in the housing 27 when the valve 28 is in its normally closed position. The valve stem head 33 is disposed below the seal 29 throughout the useful life of the aerosol dispenser 20.

0041The valve stem 31 also has a valve stem disc 32 disposed above the seal 29. The disc 32 has an associated disc diameter which is greater than the diameter of the upper stem portion 31U. The disc 32 may be annular, circumscribing the upper stem portion 31U, may comprise spokes having vectors with a radially oriented component, may comprise reinforcing ribs and any combination thereof.

0042The disc 32 limits travel of the valve stem 31 upon actuation. If the valve stem 31 is depressed too far it may not properly return to the desired normally closed position.

0043The valve stem 31 is longitudinally hollow, to allow product 42 to pass therethrough upon actuation.

0044The valve stem 31 has at least one, and typically a plurality of, radial ports disposed near the bottom of the lower stem portion 31L. The radial ports are exposed to product 42 upon actuation, allow product to enter, flow through the longitudinally hollow valve stem 28 and ultimately be dispensed. As shown, if desired, lower radial ports may be used for entry of product 42 into the valve stem 31. Larger radial ports, as shown, may be used for product 42 fill.

0045The lower stem portion 31L, upper stem portion 31U and disc 32 may be fitted together in any combination. By fitted together it is meant that two components of the valve stem 28 are separately made, then joined together after assembly of the valve stem 31 through the hole in the seal 29 and in a manner which lasts for the useful life of the aerosol dispenser 20. By joined it is meant that two components of the valve stem 28 are permanently joined together in a manner which lasts for the useful life of the aerosol dispenser 20 before a third component of the valve stem 31 is fitted thereto. Two components which are joined together may commonly be made by integrally molding as a single piece.

0046Referring to <figref idref="f0004">Figs. 3A - 3J</figref>, the disc 32 may be joined to the upper stem portion 31U. The lower stem portion 31L may be fitted to the upper stem portion 31U by inserting either such stem portion 31L, 31U through the hole in the seal 29.

0047The upper stem portion 31U and lower stem portion 31L may be fitted together by adhesion, welding, a snap fit or screw threads. A threaded fitting is used, preferably anti-rotation ratchets are present to hold the upper stem portion 31U and lower stem portion 31L in the desired position.

0048This example provides the benefit that for a particular disc 32 geometry, various lower stem portions 28L may be used to accommodate different housing 27 geometries and different seal 29 geometries. For example, lower stem portion 31L and head 33 may be suitable for a particular seal 29, while a different lower stem portion 31L and head 33 may be required for a different seal 29 geometry. This example allows the use of a single upper stem portion 31U and disc 32, with the various lower stem portions, simplifying manufacture.

0049Referring to <figref idref="f0005">Figs. 4A - 4J</figref>, in an embodiment according to the claims, the upper stem portion 31U and lower stem portion 31L may be joined together. The disc 32 may be fitted to the upper stem portion 31U after the stem 31 is inserted through the hole in the seal 29.

0050The disc 32 may be fitted to the upper stem portion 31U using a friction fit, welding, adhesion, etc. If a friction fit is selected, it may be accomplished using plural radially extending fingers 32F. The radially extending fingers 32F may extend outwardly from the upper stem portion 31U or inwardly from the disc 32. The fingers 32F may extend radially and upwardly to resist shear forces which occur when the disc 32 contacts the top of the seal 29. The fingers 32F may be spiral oriented to act as a spring and to decrease spring rate in the longitudinal direction. Alternatively, a conventional spring may be used.

0051This embodiment provides the benefit that for a particular upper stem portion 31U geometry, various discs 32 may be used to accommodate different housing 27 geometries, seal 29 geometries and other dispensing characteristics. For example, one disc 32 may be suitable for the travel of a particular actuator 25, while a different disc 32 may be required for a different actuator 25 or different seal 29 geometry. This embodiment allows the use of a single upper stem portion 31U and lower stem portion 31L, with the various discs 32 , simplifying manufacture.

0052Referring to <figref idref="f0006">Fig. 5</figref>, the upper stem portion 31U, lower stem portion 31L and disc 32 may be molded as three separate components, then fittedly assembled in any suitable order, as desired. This arrangement provides the benefit of ultimate flexibility, allowing for interchange of individual components, 31U 31L, 32, as desired. If desired, the head 33 may be molded separately from the lower stem portion 31L, allowing for the stem 31 to have four separate components.

0053This example uses a threaded connection with anti-rotation ratchets to join any of the upper stem portion 31U and disc 32 and upper stem portion 31U and lower stem portion 31L. The threaded connection provides the benefit that the overall stem 31 length may be longitudinally adjusted as desired by simply being threadedly fitted to the desired longitudinal insertion. Likewise, the disc 32 may be threadedly fitted onto the upper stem portion 31U. This arrangement provides the benefit that the disc 32 may be longitudinally disposed at any desired position on the upper stem portion 31U. Likewise, complementary snap fittings may be placed at various longitudinal positions on the upper stem portion 31U and lower stem portion 31L, to allow for various stem 31 length to occur using the same components 31L and 31U.

0054The claimed invention unexpectedly provides for flexibility in manufacture of the valves stem 31.

0055Particularly, the invention unexpectedly decouples the diameter of the disc, 32, head 33, and hole through the seal 29. Furthermore, the claimed invention unexpectedly allows for smaller diameters of

0056the longitudinal bore through the hollow valve stem 31. . Smaller diameters are particularly preferred to increase atomization and decrease particle size of the product 42 during dispensing. But typical molding operations are limited by a general rule that the core pin used to mold the bore is limited to a 3:1 length:diameter ratio, to prevent the core pin from breaking upon removal. By shortening the length, the diameter may be shortened proportionately, allowing for smaller diameters. Unexpectedly, more atomization and smaller particle sizes can prophetically be achieved using the present invention.

0057While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the scope of the invention as defined by the claims

0058. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.