Patent Description:
Aerosol 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 <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT> and <CIT>.

The outer containers are typically, but not necessarily, cylindrical. The outer container may comprise a bottom 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 <CIT> or a base cup as shown in commonly assigned <CIT> and<CIT>. Sidewalls defining the shape of the outer container extend upwardly from the bottom to an open top.

The open top defines a neck for receiving additional components of the aerosol dispenser. The industry has generally settled upon a nominal neck diameter of <NUM>, for standardization of components among various manufacturers, although smaller diameters, such as <NUM>, are also used. Various neck shapes are shown in <CIT>; <CIT>; <CIT>and <CIT>.

Typically a valve cup is inserted into the neck. The valve cup is sealed against the neck to prevent the escape of the propellant and loss of pressurization, such as described in <CIT>; <CIT>; <CIT>; <CIT> and <CIT>. 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 <CIT> and <CIT>. When the valves are opened, product may be dispensed through a nozzle, etc. as described in commonly assigned <CIT>.

A valve may be inserted into the valve cup for selective actuation by the user. The valve is typically normally closed, and may be opened to create a flow path for the product to ambient or a target surface. The valve may be compatible with local recycling standards. Suitable valves are disclosed in commonly assigned<CIT> and <CIT>.

If 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 <NUM> and plastic valve cup are used. Suitable interlocks include bayonet fittings and threads as disclosed in commonly assigned P&G Case <NUM>, serial no. A pressure vessel with a threaded bore is proposed in <CIT>.

A 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 P&G Case <NUM>, serial no. <CIT> which teaches attaching a bag to a valve cup.

If a bag configuration is desired, propellant may be disposed between the bag and outer container, as disclosed in <CIT> and in commonly assigned<CIT>and <CIT>. 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 as disclosed in commonly assigned <CIT>. Such a manufacturing process can conserve costs in production, shipment and/or storage.

An 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 <CIT>;<CIT>;<CIT>; <CIT>; <CIT> and <CIT>. 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 P&G Case <NUM>, Application no.

Alternatively, a dip tube 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. 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, particularly if highly viscous, as described in <CIT>, <CIT>and commonly assigned <CIT>.

Collectively, bags, dip tube, pistons and the associated hardware are referred to as product delivery devices. Various formats for the delivery devices may be required for different products, often complicating production. For example, one product may require a dip tube product delivery device in conjunction with a very small nozzle. The next aerosol dispenser on the production schedule may simply require changeout to a new, larger, nozzle.

But if the one wishes to manufacture multiple products, multiply different aerosol dispensers may be necessary. Different aerosol dispensers may require different valves. The valves may be attached to the outer containers by a fitting as disclosed in commonly assigned <CIT> under Case No. <NUM>. This arrangement allows different combinations of valves and outer containers to be mixed and matched as desired.

If the valve is threadedly attached to the outer container and the outer container is pressurized, it is important that the valve does not become dislodged allowing rapid and possibly catastrophic depressurization to occur. If the valve is not fully engaged, propellant pressure may expel the valve, creating a missile hazard or other safety concerns. Or a user may attempt disassembly and become injured. Regulations require aerosol dispenser to be permanently sealed.

Thus it is important the valve does not become unthreaded and lead to a missile hazard or catastrophic failure. One attempt to prevent reverse rotation is shown in <NUM>,<NUM>,<NUM>. But this attempt relies upon a selection switch to selectively provide for reverse rotation and is infeasible for the present invention. Tamper evident bands have been used in the beverage industry. But these attempts also allow for reverse rotation, and are likewise infeasible for the present invention. Also <CIT> discloses an all-plastic dispenser that comprises a tubular plastic container having cylindrical side walls and an integral transverse bottom wall, and having an externally threaded open-neck portion provided with a usual type of helical screw thread. A plastic screw cap carries a valve assembly and has a cylindrical side wall provided with internal screw threads which are cooperable with the threads of the container for securing the cap to the container neck. The screw cap and the container are provided with ratchet teeth, such that when the cap is screwed onto the container, the cooperable ratchet teeth will lock the cap in place and prevent its removal by unscrewing or turning in the opposite direction.

Accordingly, this invention is directed to the problem of how to prevent a threaded valve from becoming detached from an aerosol container by unthreading.

According to the invention, an aerosol container according to claim <NUM> is provided.

The invention comprises an aerosol container having a longitudinal axis and being usable for an aerosol dispenser. The aerosol container comprises an outer container having a closed end bottom, a threaded open neck longitudinally opposed thereto, the open neck having a periphery and a complementary valve threadedly disposed therein. One of the neck and the valve having at least one pawl or ratchet, the pawl or ratchet allowing threaded rotation of the complementary valve onto the outer container in an onward direction, and impeding rotational detachment of the valve therefrom in a removal direction. The other of the valve and the outer container has at least one co-acting ratchet or pawl, preventing removal of the valve from the outer container. The valve is externally helically threaded.

The drawings are to scale, unless otherwise noted as schematic. The onward direction is clockwise in the drawings unless otherwise stated.

Referring to <FIG>, an aerosol dispenser <NUM> and aerosol container 20C, each having a longitudinal axis, are shown, respectively. The aerosol dispenser <NUM> comprises a pressurizeable outer container <NUM> usable for such an aerosol dispenser <NUM>. In an example not according to the claims, the outer container <NUM> has a neck <NUM> into which a valve cup <NUM> is sealingly disposed. A valve <NUM> and actuator <NUM> may be disposed in the valve cup <NUM> for selective dispensing of product <NUM> from the aerosol dispenser <NUM>. A seal <NUM> having a surface for sealing a valve <NUM> to the valve cup <NUM> may be disposed below the valve cup <NUM> and valve <NUM> to prevent escape of product <NUM> to ambient. As used herein, an aerosol container 20C may be a subset of an aerosol dispenser <NUM>, and have an outer container <NUM>, valve cup <NUM> sealed thereto with a bag <NUM>/dip tube <NUM>, collectively referred to as a product delivery device <NUM>, <NUM>, joined to the valve cup <NUM>, and optionally propellant <NUM>, but not necessarily a valve <NUM>, actuator <NUM>, labeling, etc. Optionally the valve <NUM> may be directly joined to the outer container <NUM> without a separate valve cup <NUM>.

As used herein, the top of the aerosol dispenser <NUM> or the outer container <NUM> is taken as the uppermost part, when the aerosol dispenser <NUM> or container <NUM> is vertically oriented in its normal use or storage position.

As used herein, the bottom of the aerosol dispenser <NUM> or the outer container <NUM> is taken as the lowermost part, when the aerosol dispenser <NUM> or the container <NUM> is vertically oriented in its normal use or storage position. The top and bottom are longitudinally opposed, with the top typically being open at a neck <NUM> and bottom typically being a closed end. The terms 'above' and 'below' refer to relative positions towards and away from the top, respectively. Likewise the terms 'above' and 'below' refer to relative positions away from and towards the bottom, respectively.

The aerosol dispenser <NUM> and outer container <NUM> have a longitudinal axis, defining the main axis. The aerosol dispenser <NUM> and outer container <NUM> may be longitudinally elongate, i.e. having an aspect ratio of longitudinal dimension to transverse dimension[s] such as diameter greater than <NUM>, an aspect ratio equal to <NUM> as in a sphere or shorter cylinder, or an aspect ratio less than <NUM>.

The outer container <NUM> may comprise metal or preferably plastic, as are known in the art. The plastic may be polymeric, and particularly comprise polyethylene terephthalate (PET) or polypropylene (PP) for all of the components described herein. The outer container <NUM> may be injection molded or further blow molded in an ISBM process, as well known in the art. The outer container <NUM> defines a longitudinal axis and may have an opening at one end thereof. The opening is typically at the top of the pressurizeable container when the pressurizeable container is in its-in use position.

As the top of the outer container <NUM> is approached, the outer container <NUM> has a neck <NUM>. The opening defines a neck <NUM>, to which other components may be sealingly joined. The neck <NUM> may be connected to the container sidewall by a shoulder <NUM>. The shoulder <NUM> may more particularly be joined to the sidewall by a radius. The shoulder <NUM> may have an annular flat. The neck <NUM> may have a greater thickness at the top of the outer container <NUM> than at lower portions of the neck <NUM> to provide a differential thickness. Such differential thickness may be accomplished through having an internally stepped neck <NUM> thickness.

A normally closed valve <NUM> is disposed in the neck <NUM>. The valve <NUM> is openable upon demand by a user, in response to manual operation of an actuator <NUM>. The actuator <NUM> may be depressable, operable as a trigger, etc. to spray product <NUM> from the aerosol dispenser <NUM>. Illustrative and non-limiting products <NUM> include shave cream, shave foam, body sprays, body washes, perfumes, cleansers, air treatments, astringents, foods, paint, insecticides, etc..

The valve <NUM> or valve cup <NUM> may be sealed to the neck <NUM> of the outer container <NUM> using class <NUM> TPE material. Polyester based TPE sold by Kraiburg TPE GmbH & Co KG of Waldkraiburg, Germany under the name HTC8791-<NUM> and sold by DuPont of Delaware under the name HYTEL may be used for good resistance to Silicone and adhesion to PET. Such a TPE material is believed to fall under Resin Identification Code <NUM>/<NUM> for PETE/PET, as set forth above by the Society of Plastics Industry and ASTM D7611. Or a Styrenic bloc copolymer based TPE such as Kraiburg HTC8791-<NUM> or Krayton elastomer may be used, providing easier process and lower density. Other seal materials include silicone, rubber and similar conformable materials.

In an example, not according to the claims, a valve <NUM>, in turn, may be disposed within the valve cup <NUM>. The valve <NUM> provides for retention of product <NUM> within the aerosol dispenser <NUM> until the product <NUM> is selectively dispensed by a user. The valve <NUM> may be selectively actuated by an actuator <NUM>. A nozzle <NUM> and related valve <NUM> components may optionally be included, depending upon the desired dispensing and spray characteristics. The valve <NUM> may be attached using conventional and known means. The valve <NUM> and actuator <NUM> may be conventional and do not form part of the claimed invention, except as provided herein.

The valve <NUM> and valve cup <NUM> may be integral and formed by a single injection molding operation. Or the valve <NUM> and valve cup <NUM> may be joined using known means. The valve <NUM> may be a normally closed valve <NUM>. A normally closed valve <NUM> is closed in its rest position. The valve <NUM> is only opened when actuated upon demand by a user.

The components of the valve <NUM> may be joined to a common valve housing <NUM>. The housing <NUM> acts as a chassis for the other valve components and joins the valve <NUM> to the neck <NUM> of the outer container <NUM> or preform <NUM>. A valve stem <NUM> provides a product <NUM> flow path and joins the actuator <NUM> to the valve <NUM> in fluid communication. The valve stem <NUM> may be disposed within and cause responsive movement in the moving assembly <NUM>. The valve stem <NUM> has a valve stem distal end, taken as the uppermost portion of the valve stem <NUM> without an actuator <NUM> or other attachment. The valve <NUM> may have blades 28B, to allow for a chuck to rotationally attach the valve <NUM>.

The valve <NUM> is externally helically threaded. The threads <NUM> may or may not circumscribe the neck <NUM>, as desired. One or more threads <NUM> may be utilized, with four threads <NUM>, each thread <NUM> subtending about <NUM> degrees having been found suitable. The valve <NUM> is assembled by screwing onto the complementary threads <NUM>. The assembly of the valve <NUM> onto outer container <NUM> is intended to be permanent.

Selective actuation of the valve <NUM> allows the user to dispense a desired quantity of the product <NUM> on demand. Illustrative and non-limiting products <NUM> include shave cream, shave foam, body sprays, body washes, perfumes, cleansers, air fresheners, astringents, foods, paint, etc..

The product delivery device <NUM>, <NUM> may be used to contain and/or provide for delivery of product <NUM> from the aerosol dispenser <NUM> upon demand. Suitable product delivery devices <NUM>, <NUM> comprise pistons, bags <NUM>, dip tubes <NUM> (as shown in phantom), and do not form part of the claimed invention.

If desired, the product delivery device <NUM>, <NUM> may further comprise a metering device for dispensing pre-determined, metered quantities of product <NUM>, as described in <NUM>,<NUM>,<NUM>; <NUM>,<NUM>,<NUM> and <NUM>,<NUM>,<NUM>. The product delivery device <NUM>, <NUM> may also comprise an inverting valve having a ball therein to alter product <NUM> flowpath.

If desired the product delivery device <NUM>, <NUM> may comprise a dip tube <NUM> disposed in a bag <NUM>. Such a dip tube <NUM> may reach to nearly the bottom of the bag <NUM>, or be juxtaposed near the middle of the bag <NUM>. A dip tube may be made according to <NUM>,<NUM>,<NUM>.

The bag <NUM> may be directly attached to the valve cup <NUM>. Particularly, bag <NUM> may be integrally injection molded with the valve cup <NUM>. If the preform <NUM> is to be stretched into a bag <NUM>, the preform <NUM> may have a wall thickness of <NUM> to <NUM>. The resulting bag <NUM> is collapsible upon depletion of product <NUM> therefrom. The resulting bag <NUM> may have a thickness of <NUM> to <NUM>.

One of skill will recognize the preform <NUM> may be used to make the outer container <NUM> or a bag <NUM> for use with the aerosol container <NUM> of this invention. One of skill will recognize a bag <NUM> is commonly used to contain product <NUM> and keep such product <NUM> isolated from the propellant <NUM>.

The pressurizeable container may further include a propellant <NUM>. The propellant <NUM> may comprise hydrocarbons, nitrogen, air and mixtures thereof. Nonflammable propellant <NUM> listed in the US Federal Register <NUM> CFR <NUM>, Class <NUM>, Division <NUM> are also considered acceptable. The propellant <NUM> may particularly comprise a Trans-<NUM>,<NUM>,<NUM>,<NUM>-tetrafluoroprop-<NUM>-ene, and optionally a <NPL> gas. One such propellant <NUM> is commercially available from Honeywell International of Morristown, New Jersey under the trade name HFO-1234ze or SOLSTICE.

If desired, the propellant <NUM> may be condensable. Generally, the highest pressure occurs after the aerosol dispenser <NUM> is charged with product <NUM> but before the first dispensing of that product <NUM> by the user. A condensable propellant <NUM>, when condensed, provides the benefit of a flatter depressurization curve at the vapor pressure, as product <NUM> is depleted during usage. A condensable propellant <NUM> also provides the benefit that a greater volume of gas may be placed into the container at a given pressure. A condensable propellant <NUM>, such as HFO-1234ze, may be charged to a gage pressure of <NUM> - <NUM> kPa at <NUM> degrees C.

A manifold may supply propellant <NUM>, under pressure, through at least one channel between the valve cup <NUM> and container neck <NUM>. The manifold may be retractingly disposed above the container <NUM>. The manifold may be brought into contact with the valve cup <NUM>, forming a temporary seal therebetween. Suitable channels are particularly described in commonly assigned <CIT>at <FIG>, column <NUM>, lines <NUM> to column <NUM>, line <NUM> and column <NUM>, lines <NUM> - <NUM>. While the temporary seal is established between the manifold and valve cup <NUM>, the propellant <NUM> may be charged into the outer container <NUM>.

The aerosol dispenser <NUM>, as presented to a user may have an initial pressure. The initial pressure is the highest pressure encountered for a particular filling operation, and corresponds to no product <NUM> yet being dispensed from the product delivery device <NUM>, <NUM>. As product <NUM> is depleted, the outer container <NUM> approaches a final pressure. The final pressure corresponds to depletion of substantially all product <NUM>, except for small residual, from the product delivery device <NUM>, <NUM>. One benefit of the invention is that the residual product <NUM>, remaining at end of life, is unexpectedly minimized.

This arrangement provides the benefit that propellant <NUM> may be charged to a lesser pressure than the desired starting pressure, decreasing propellant <NUM> charge time and reducing pressure applied to the charging machinery. Another benefit is that propellant <NUM> is disposed as needed for the end use when the aerosol dispenser <NUM> is ready for sale, product <NUM> fill and upon product <NUM> depletion may be recharged with product <NUM> and reused.

At <NUM> degrees C, the outer container <NUM> may be pressurized to an internal gage pressure of <NUM> to <NUM>, <NUM> to <NUM> or <NUM> to <NUM> kPa. A particular aerosol dispenser <NUM> may have an initial propellant <NUM> pressure of <NUM> kPA and a final propellant <NUM> pressure of <NUM> kPa, an initial propellant <NUM> pressure of <NUM> kPA and a final propellant <NUM> pressure of <NUM> kPa, an initial propellant <NUM> pressure of <NUM> kPA and a final propellant <NUM> pressure of <NUM> kPa, and any values therebetween.

If desired, the outer container <NUM>, valve cup <NUM>, valve <NUM>, and/or piston 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, and more particularly PET. Thus, the entire aerosol dispenser <NUM> or, specific components thereof, may be free of metal, allowing microwaving. Microwave heating of the aerosol dispenser <NUM> or pressurizable container therefor provides for heating of the product <NUM> prior to dispensing. Heating of the product <NUM> prior to dispensing may be desirable if the product <NUM> is applied to the skin, becomes more efficacious at lower viscosities, or is to be eaten.

The outer container <NUM>, and all other components, optionally excepting the TPE seal, may comprise, consist essentially of or consist of PET, PEN, Nylon, EVOH or blends thereof to meet DOT SP <NUM>. All such materials may be selected from a single class of recyclable materials, as set forth above by the Society of Plastics Industry and ASTM D7611. Particularly all components of the aerosol dispenser <NUM> may comprise the aforementioned TPE and PET/PETE, Resin Identification Code <NUM>/<NUM>. This material selection provides the benefit that the entire aerosol dispenser may advantageously be recycled in a single stream.

Alternatively, the valve cup <NUM> and/or bag <NUM> may comprise plural layers such as nylon with EVOH, PET and/or polyolefin materials. Three layers may be utilized, such as PET/Nylon/PET or PET/EVOH/PET. The layers may be co-molded or overmolded. The multi-layer arrangements may provide increased barrier resistance and reduced failure rates.

The outer container <NUM>, and/ optionally the product delivery device <NUM>, <NUM>, may be transparent or substantially transparent. This arrangement provides the benefit that the consumer knows when product <NUM> is nearing depletion and allows improved communication of product <NUM> attributes, such as color, viscosity, etc. Also, labeling or other decoration of the container may be more apparent if the background to which such decoration is applied is clear.

Suitable decoration includes labels <NUM>. Labels <NUM> may be shrink wrapped, printed, etc., as are known in the art.

The outer container <NUM> may define a longitudinal axis of the aerosol dispenser <NUM>. The outer container <NUM> 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 <NUM> may be barrel shaped, hourglass shaped, or monotonically tapered.

The outer container <NUM> may range from <NUM> to <NUM>, and particularly <NUM> to <NUM> in height, taken in the axial direction and from <NUM> to <NUM>, and particularly <NUM> to <NUM> in diameter if a round footprint is selected. The outer container <NUM> may have a volume ranging from <NUM> to <NUM> cc exclusive of any components therein, such as a product delivery device <NUM>, <NUM>. The outer container <NUM> may be injection stretch blow molded. If so, the injection stretch blow molding process may provide an overall stretch ratio of greater than <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM> and less than <NUM>, <NUM> or <NUM>.

The outer container <NUM> may sit on a base. The base is disposed on the bottom of the outer container <NUM>. Suitable bases include petaloid bases, champagne bases, hemispherical or other convex bases used in conjunction with a base cup. Or the outer container <NUM> may have a generally flat base with an optional punt.

Referring generally to <FIG> and examining the invention in more detail, the valve <NUM> and outer container <NUM>, specifically at the neck <NUM> thereof, have a complementary ratchet <NUM> and pawl <NUM> arrangement. As used herein a pawl <NUM> is an extending member, generally cantilevered and which can rotate with the valve <NUM>, as it is threaded into place.

The pawl <NUM> may co-actingly intercept a complementary ratchet. As used herein a ratchet <NUM> is a member which intercepts a pawl, allowing the pawl <NUM> to move in a first direction, but not in a second, opposed direction.

A ratchet, and preferably a plurality of ratchets <NUM>, may be disposed around the periphery of the neck <NUM>. The ratchets <NUM> may be stationary relative to the neck <NUM> and not rotate as the valve <NUM> is threaded into place. More preferably, the ratchets <NUM> circumscribe the neck <NUM> of the outer container <NUM>.

The ratchets <NUM> may comprise sprags, cams, and other structural features which allow only unidirectional rotational motion. The sawtooth ratchet <NUM> has two surfaces, a sloped onward surface and a generally perpendicular stop surface. The ratchet <NUM> may rise to a crest or to a flat, as desired. The pawls <NUM> and ratchets <NUM> may have different geometries, as shown or may have identical geometry. If the onward direction is clockwise, the reverse or removal direction is counter-clockwise and vice versa. Both clockwise and counterclockwise rotations are contemplated hereunder.

The cam surfaces allow movement in the onward direction, according to the incline of the sloped onward surfaces. The stop surface is generally perpendicular to the circumferential rotation direction, to impede rotational detachment and reverse movement of the valve <NUM>. By impede it is meant that the valve <NUM> does not undergo reverse rotation, and possible loosening/disassembly from the neck <NUM>, without undue and unintended torque applied thereto. Preferably the ratchets <NUM> and pawls <NUM> completely prevent discernable reverse rotation or subsequent disassembly of the valve <NUM>. Tamper evident bands, which indicate a valve <NUM> or other component of the aerosol dispenser <NUM> has been removed are not within the scope of the claimed invention.

Either of the pawls <NUM> and ratchets <NUM> are disposed on the valve <NUM>, providing a complementary ratchet <NUM> or pawl <NUM> is disposed on the outer container <NUM>. By complementary, it is meant the ratchets <NUM> and pawls <NUM> are sized to fit together, allowing movement in the onward direction, and preventing improper movement in the reverse direction. Also the ratchets <NUM> and pawls <NUM> are disposed on a nominally common, and preferably coincident, diameter.

Since the ratchets <NUM>/pawls <NUM> do not allow for reverse rotation, but do allow for onward movement, no additional tooling is required in manufacture and the permanent threaded attachment of the valve <NUM> to the aerosol container 20C and ultimately the aerosol dispenser <NUM>, and occurs automatically and without requiring an extra step during manufacture.

The disclosure is directed to equal numbers of plural ratchets <NUM> and pawls <NUM>, equally spaced about the longitudinal axis, the invention is not so limited. The disclosure is also directed to unequal numbers of ratchets <NUM> and pawls <NUM>, single ratchets <NUM>, single pawls <NUM>, unequally spaced ratchets <NUM> and/or unequally spaced pawls <NUM> are contemplated and within the scope of the present invention.

Referring particularly to <FIG>, the outer container <NUM> may have radially outwardly extending pawls <NUM>. A complementary valve housing <NUM> may radially inwardly extending ratchets <NUM>, it being generally preferred that the ratchets <NUM>/pawls <NUM> not be disposed on the moving assembly <NUM> to prevent inadvertent dislodgement during operation of the valve <NUM>. Preferably the valve <NUM> is threaded into the neck <NUM> of the outer container <NUM>, to provide a smaller effective diameter. The pawls <NUM> engage the ratchets <NUM> upon threaded assembly of the valve <NUM> to the neck <NUM> of the outer container <NUM>.

Referring to <FIG>, the ratchets <NUM>/pawls <NUM> may be generally equally spaced and equal in number. If the ratchets <NUM>/pawls <NUM> are relatively small, so that e.g. at least <NUM>, and preferably at least <NUM>, ratchets <NUM>/pawls <NUM> are spaced about the circumference of a commonly sized neck <NUM> of an aerosol dispenser <NUM>, this arrangement provides the benefit that greater precision and torque control are achievable as the valve <NUM> is threaded onto the outer container <NUM>.

Referring to <FIG>, the ratchets <NUM>/pawls <NUM> may be generally unequally spaced and/or unequal in number. This arrangement provides the benefit of conserving material at constant valve housing <NUM> diameter.

A geometry having radially extending ratchets <NUM>/pawls <NUM> provides the benefit that increased torque occurs during attempted reverse rotation of the valve. The increased torque provides increased resistance to undesired removal of the valve <NUM>.

Referring particularly to <FIG>, conversely, the valve <NUM> may have radially outwardly extending ratchets <NUM> and an outer container <NUM> may have radially inwardly extending pawls <NUM>. In a degenerate case, the ratchets <NUM> and pawls <NUM> may be identical in geometry, as shown in <FIG> having sawtooth ratchets <NUM> and pawls <NUM>. This embodiment provides the benefit that the ratchets <NUM> and pawls <NUM> are identical and interchangeable.

Thus, either of the pawls <NUM> or ratchets <NUM> may be disposed on the outer container <NUM>. Again, the pawl <NUM> or ratchet <NUM> disposed on the outer container <NUM> may be integrally molded with the preform <NUM> used to make the outer container <NUM>.

The other of the ratchets <NUM> and pawls <NUM> may be co-actingly disposed on the valve <NUM>. This radial geometry provides the benefit of increased torque between the ratchets <NUM> and pawls <NUM> as the valve <NUM> is further threaded onto the outer container <NUM>.

Referring to <FIG>, the pawls <NUM> and ratchets <NUM> may predominantly extend in the longitudinal direction and in a degenerate case may be parallel to the longitudinal axis. One of the pawls <NUM> and ratchets <NUM> are disposed on the outer container <NUM>. If desired, the pawl <NUM> or ratchet <NUM> disposed on the outer container <NUM> may be integrally molded with the preform <NUM> used to make the outer container <NUM>.

The other of the ratchets <NUM> and pawls <NUM> are co-actingly disposed on the valve <NUM>. This geometry provides the benefit of increased engagement between the ratchets <NUM> and pawls <NUM> as the valve <NUM> is further threaded onto the outer container <NUM>. This embodiment provides the benefit of confining the ratchet <NUM> and pawl <NUM> configuration to a more compact footprint and diameter within the aerosol dispenser <NUM>.

Referring to <FIG>, a hybrid embodiment may be utilized. The hybrid embodiment has longitudinally extending ratchets <NUM> and radially extending pawls <NUM>, or vice versa. The ratchets <NUM>/pawls <NUM> may be disposed on the preform <NUM> and, upon blowmolding, are disposed on the outer container <NUM>. The pawls <NUM> may extend radially inwardly or radially outwardly, as sized to intercept the ratchets <NUM>. The ratchets <NUM> may extend longitudinally upwardly, to automatically engage the pawls <NUM> as the valve <NUM> is threaded onto the outer container <NUM>.

A valve housing <NUM> having radially outwardly extending pawls <NUM> and an outer container <NUM> having longitudinally upwardly extending ratchets <NUM> is shown. One of skill will understand, that, like the previous embodiments, the disposition of the ratchets <NUM> and pawls <NUM> may be transposed so that the ratchets <NUM> are on the valve <NUM> and the pawls <NUM> are on the outer container <NUM>. Or the outer container <NUM> may have radial ratchets <NUM>/pawls <NUM> while the valve <NUM> has longitudinal and complementary pawls <NUM>/ratchets <NUM>.

Again, the pawls <NUM> may be disposed on the valve <NUM> and the ratchets <NUM> disposed on the preform <NUM>, which upon blowmolding, are disposed on the outer container <NUM>. The hybrid embodiment provides the benefit that high torque can be utilized.

Referring to <FIG>, the valve <NUM> may have an optional sheath 28P to protect valve stem <NUM>. The valve <NUM> may have one or more optional blades 28B to assist in fitting the valve <NUM> into the neck <NUM> of the outer container <NUM> and within the sheath <NUM>. One or more pawls <NUM> may extend inwardly from the sheath <NUM>. The pawls <NUM> may intercept a groove on the outside of the valve <NUM>. The groove may have one or more complementary ratchets <NUM> therein, which intercept the inwardly extending pawls <NUM> to allow onward rotation but not reverse rotation. This embodiment provides the benefit that both anti-rotation capability and protection of the valve stem <NUM> by the sheath 28P can be incorporated into a single assembly. Again, the ratchets <NUM> and pawls <NUM> may be transposed so that either is disposed on the sheath 28P.

Referring to <FIG>, a threaded fitting, that is not according to the invention, includes a bayonet fitting <NUM>. A bayonet fitting <NUM> may have a projection <NUM> and complementary slot <NUM>. The projection <NUM> is threaded into in the slot <NUM>, preferably with a combination of axial and rotational circumferential motions. The bayonet fitting <NUM> holds the valve <NUM> to the neck <NUM> of the outer container <NUM>. The slot <NUM> may be on the outer container <NUM> and projection <NUM> on the valve <NUM>, or vice versa. Any of the aforementioned arrangements, dispositions and combinations of ratchets <NUM>/pawls <NUM> may be used with the bayonet fitting <NUM> configuration.

Generally, it is to be understood that a single ratchet <NUM> and single pawl <NUM> may be suitable for any of the embodiments described herein. Plural ratchets <NUM> and plural pawls <NUM> are preferred to provide load sharing when torque in the reverse direction is applied. The ratchets <NUM> and pawls <NUM> are preferably equally circumferentially spaced, to further equalize torque about the longitudinal axis. The ratchets <NUM> may be mutually equally sized and shaped or be mutually unequally sized and shaped. Likewise, the pawls <NUM> may be mutually equally sized and shaped or be mutually unequally sized and shaped, so long as they co-act with the ratchets <NUM>, as described herein. While the invention comprises a threaded attachment, examples not falling within the scope of the claims are possible. A valve <NUM> having a bayonet fitting may be used with the ratchets <NUM> and pawls <NUM> described herein, to prevent undesired removal of such a valve <NUM>. The fitting <NUM> may allow for engagement of the valve cup <NUM> with the neck <NUM> of the container <NUM> to occur in either the clockwise direction or the counterclockwise direction. The invention may comprise ratchets <NUM> and pawls <NUM> disposed on a common diameter or disposed on different, plural diameters. The ratchets <NUM> and pawls <NUM> need not extend identically radially or identically longitudinal. Prophetically, diagonal orientations are suitable, so long as the ratchets <NUM> and pawls <NUM> are complementary and co-act as described above.

Claim 1:
An aerosol container (<NUM>) having a longitudinal axis and being usable for an aerosol dispenser (<NUM>), said aerosol container (<NUM>) comprising:
an outer container (<NUM>) having a closed end bottom, a threaded open neck (<NUM>) longitudinally opposed thereto, said open neck (<NUM>) having a periphery and a complementary valve (<NUM>) threadedly disposed therein, one of said neck (<NUM>) and said valve (<NUM>) having at least one pawl (<NUM>) or ratchet, said pawl (<NUM>) or ratchet (<NUM>) allowing threaded rotation of said complementary valve (<NUM>) into said outer container (<NUM>) in an onward direction, and impeding rotational detachment of said valve (<NUM>) therefrom, the other of said valve (<NUM>) and said neck (<NUM>) having a co-acting ratchet (<NUM>) or pawl (<NUM>), preventing removal of said valve (<NUM>) from said outer container (<NUM>); characterized in that said valve (<NUM>) is externally helically threaded.