Patent Abstract:
A mechanically pressurized aerosol dispensing system comprising a cap which houses a piston, an actuator moveably attached to the cap, forming together with the cap a dispensing head assembly, and an expandable elastic reservoir. The system is fitted over a standard container holding a liquid product, and includes a dip tube assembly to draw liquid into the dispensing head assembly, where the contents are released through the dispensing head assembly, via the aerosol nozzle and valve. A twist of the threaded cap raises a piston, thereby opening a charging chamber within the dispensing head assembly. This creates a vacuum with the resulting suction pulling the product up through the dip tube to fill the charging chamber. Twisting the cap in the opposite direction lowers the piston in a downstroke which closes the charging chamber, forcing the product into the expandable elastic reservoir where it is then discharged through the nozzle.

Full Description:
BACKGROUND OF INVENTION 
     1. Field of Invention 
     The present invention relates to dispensers generally, and more specifically, to aerosol dispensers that are pressurized by mechanical energy instead of chemical energy. 
     2. Description of the Related Art 
     Aerosol dispensers have been in use for more than fifty years, and continue to gain in popularity because of the convenience of their use. However, many of those dispensers rely upon chemical propellants, including chloro-fluorocarbons and hydrocarbon compounds to pressurize the product. The use of chemical pressurizing agents creates special problems, including safety concerns in filling, shipping, handling, storing, using and disposing the pressurized, and often flammable containers. Another set of concerns involves questions relating to the effect of certain pressurizing chemical agents upon the earth&#39;s ecosystem, including particular questions concerning their effect on the ozone layer, and questions concerning the effect of the release of volatile organic compounds into the atmosphere. Accordingly, there has been great interest in the development of aerosol dispensers that do not use chemical propellants, but which also retain the conveniences of use associated with the chemically charged dispensers. 
     Among the alternatives to chemically pressurized aerosol dispensers are various mechanically pressurized models using finger pumps and triggers. These typically require a continued vigorous pumping to produce a continuous spray, and, as a result, are inconvenient to use. Further, the duration of the spray is in most instances limited by (1) the length of the stroke of the pump or trigger, (2) the fact that the pressure of the spray in most instances does not remain constant during a discharge cycle but decreases rapidly near the end of the cycle with the spray becoming a wet stream or dribble, and (3) the fact that the device must generally be operated in an upright position. In addition, many of the finger-operated pumps are not capable of producing a fine mist or suitably atomized spray for use with such products as cosmetics and hair sprays. As a result, such devices only partially solve the problem of providing a convenient, yet safe alternative to chemically pressurized aerosol dispensers. 
     Other alternatives to chemically pressurized dispensers include various mechanically pressurized models that obtain prolonged spray time by storing a charge without the use of chemical propellants. Such “stored charge” dispensers include types that are mechanically pressurized at the point of assembly, as well as types that may be mechanically pressurized by an operator at the time of use. 
     Stored charge dispensers that are pressurized at the point of assembly often include a bladder that is pumped up with product. Examples include those described in U.S. Pat. Nos. 4,387,833 and 4,423,829. 
     Stored charge dispensers that are pressurized by an operator at the time of use typically include charging chambers that are charged by way of screw threads, cams, levers, ratchets, gears, and other constructions providing a mechanical advantage for pressurizing a product contained within a chamber. This type of dispenser will be referred to as a “charging chamber dispenser.” Many ingenious charging dispensers have been produced. Examples include those described in U.S. Pat. No. 4,872,595 of Hammett et al., U.S. Pat. No. 4,222,500 of Capra et al., U.S. Pat. No. 4,174,052 of Capra et al., U.S. Pat. No. 4,167,941 of Capra et al., and U.S. Pat. No. 5,183,185 of Hutcheson et al., which is expressly incorporated by reference herein. 
     While some of the prior stored charge dispensers avoid some or all of the difficulties of the finger pump or trigger dispensers, the stored charge dispensers tend to have drawbacks of their own. In the devices pressurized at the point of assembly, the charging chamber is often an elastic bladder that remains charged during the life of the product, degrading over time, and these devices typically cannot be refilled with product. In the devices pressurized by an operator at the time of use, the charging chamber devices have been relatively difficult to manufacture due the large number of interrelated working parts required, and/or the fact that they are composed of parts not readily suited to high quantity, high yield injection molding production techniques, and/or the fact that they are required to be used with specially designed containers. 
     These drawbacks have tended to make the charging chamber dispensers expensive and not commercially feasible for mass market applications, and have tended to make other stored charge dispensers less than completely satisfactory substitutes for chemically pressurized dispensers. Accordingly, existing stored charge and charging chamber dispensers have only partially solved the problem of providing a convenient, yet safe alternative to chemically pressurized aerosol dispensers. 
     The current invention is a charging chamber dispenser that possesses specific improvements so that it combines convenience of use with commercial feasibility. It is believed that this is, finally, a non-chemical aerosol dispenser that retains the desirable features commonly associated with chemical aerosols, and is, therefore, a non-chemical aerosol dispenser that can attain widespread vendor and customer acceptance. 
     SUMMARY OF THE INVENTION 
     Accordingly, the mechanically pressurized aerosol dispensing system of this invention in one of the preferred embodiments consists essentially of: (a) a cap which houses a piston; (b) an actuator moveably attached to the cap, forming together with the cap a dispensing head assembly; and (c) an expandable elastic reservoir. The system is fitted over a standard container holding a liquid product, and includes a dip tube assembly to draw liquid into the dispensing head assembly, including an aerosol nozzle and valve, to release the contents out of the dispensing head assembly. 
     Complementary screw threads on the cap and actuator are selectively pitched so that a short twist of the threaded cap raises the piston, opening a charging chamber within the dispensing head assembly. This creates a vacuum with the resulting suction pulling the product up through the dip tube to fill the charging chamber. Twisting the cap in the opposite direction lowers the piston in a downstroke which closes the charging chamber, forcing the product into the expandable elastic reservoir. The reservoir expands under pressure, holding the product for subsequent discharge. Pushing a button, which is part of the standard valve assembly in the cap, releases the product through the nozzle. 
     The general working of the system briefly summarized above is enhanced by several specific improvements, including: (a) use of a snap-in piston so that the piston and the cap may be separately molded, allowing different materials for each and easier mold forms; (b) use of a container which is a separate piece from the dispensing head assembly, permitting easy filling of the container, and taking advantage of ordinary bottles and standard bottling technology; (c) use of a reservoir, piston and actuator in such a way as to realize the additional advantages of establishing a one-way valve mechanism for sealing the dip tube on the downstroke cycle, and also establishing a drain back mechanism for discharging undispensed product back into the container without the need of extra parts for either function, (d) use of a piston sealing mechanism which produces a tight seal while maintaining a low coefficient of friction so as to make the mechanical twisting motions of the cap and actuator easy, and (e) use of a flexible face fitment two-way valve mechanism for providing a positive shut off to reduce dribbling or seeping, while also preventing product build up behind the nozzle. 
     These and other specific improvements (and other embodiments) will be described in more detail later, and their significance will be explained. In summary, it is the cooperation of such elements as these in the system of this invention which results in a non-chemical aerosol that works from any position/orientation, even upside down, that does not require a finger pump to actuate, and that can be fitted to a wide variety of standard disposable or reusable containers. Further, the system of this invention produces a longer duration spray which does not become a wet stream or dribble near the end of the cycle, and a finely atomized high pressure spray which does not take inordinate mechanical force to charge. The system of this invention is simple and uses relatively few parts, all of which can be easily fabricated from existing materials and can be injection molded with existing mold techniques. 
     It is a specific objective of the system of this invention to solve substantially all of the problems that have, until now, prevented non-chemical aerosol dispensers from being widely accepted as the replacement for chemically pressurized aerosol dispensers. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in, and form a part of the specification, illustrate the preferred embodiments of the present invention, and together with the descriptions serve to better explain the principles of the invention. 
     In the Drawings 
     FIG. 1 is an offset front view of this invention particularly featuring the actuator, the acuator housing, and the collar cap. 
     FIG. 2 is a front view of the actuator assembly of this invention shown here without a mechanical break-up unit (MBU). 
     FIG. 3 is a sectional side view of the actuator assembly of FIG. 2, again shown without an MBU. 
     FIG. 4 is a side view of this invention showing the overcap, the actuator housing, the collar cap, and the container. 
     FIG. 5 is a sectional side view of one embodiment of the dispenser invention shown in FIG. 4, specifically the double helix action (DHA) model, which is shown here with the piston in the down position. 
     FIG. 6 is a sectional side view of the DHA model of FIG. 5, but is shown here with the piston in the up position. 
     FIG. 7 is an exploded view of the individual components that together comprise the DHA model of FIGS. 5 and 6. 
     FIG. 8 is a sectional side view of a second embodiment of the dispenser invention shown in FIG. 4, specifically the basic single helix action (SHA) model, which is shown with the piston in the down position. 
     FIG. 9 is an exploded view of the individual components that together comprise the basic SHA model of FIG.  8 . 
     FIG. 10 is a blown-up representation of the two-part valve mechanism that is integral to each of the embodiments of this invention. 
     FIG. 11 is an exploded view of the individual components that together comprise a third embodiment of the dispenser invention shown in FIG. 4, the simplified single helix action (SHA) model, specifically showing the elimination of several parts as compared to the embodiments shown in FIGS. 7 and 9. 
     FIG. 12 is a sectional side view showing the embodiment of FIG. 11 with the piston in the down position. 
     FIG. 13 is a sectional side view showing the embodiment of FIG. 11 with the piston in the up position. 
     FIG. 14 is a sectional side view showing the embodiment of FIG. 11, as a sectional side view in 90 degree rotation from the cross-section of FIG. 12, particularly pointing out the vent holes, open to the atmosphere when the piston is fully extended, which allow the system to re-establish equilibrium. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With the above summary in mind, it may now be helpful in fully understanding the inventive features of the present invention to provide in the following description a thorough and detailed discussion of a number of specific embodiments of the invention. 
     Most generally, and referring to FIGS. 1,  4 ,  7 ,  9  and  11  for purposes of illustration, it may be seen in overview that the non-chemical aerosol dispenser system  10  generally comprises an actuator assembly  20  (shown in FIGS. 2 and 3 without an actuator housing  22 ), a collar cap assembly  40 , shown in FIG. 9 to include a threaded collar cap  42  housing a piston  44  in combination with a spindle  46 , and interconnected with a cylindrical housing  50  by a piston collar  48 , and an expandable elastic reservoir  60 . As shown in FIGS. 7,  9  and  11 , the dispenser system  10  fits onto the collar of a standard container  70 . In all of the disclosed embodiments discussed below, the container  70  may be any standard container, and it does not need to be specially made to withstand a minimum gas pressure. Since the container  70  is not pressurized, it also does not need to be cylindrical or round in shape, nor does it need to be constructed with heavy or thick material. In fact, there are no apparent geometrical limitations placed on the container  70 , thus enabling the dispenser system  10  to have a virtually unlimited range of possible consumer uses, including the possibility of its use with food products. Moreover, the container  70  can be disposable or reusable, and it can be filled and refilled readily with ordinary techniques known to those persons skilled in the art. In summary, unlike chemically propelled aerosols, the current invention is readily adaptable to a wide variety of products characterized by a wide variety of viscosities, surface tensions, formulations, etc., and it can further be configured in a wide variety of product-specific or consumer-specific packaging options. Such container interchangeability is well known by persons skilled in the art and is not further described herein. 
     The expandable elastic reservoir  60  as illustrated in all of the disclosed embodiments discussed below, is shown in FIGS. 7,  9  and  11 , and is described as an elastomeric bladder, but it may be any kind of reservoir which can expand under pressure, thus storing a force. Accordingly, the reservoir  60  should be understood to represent, not only the elastomeric bladder of these embodiments, but more generally, a means for resistably expanding a reservoir under hydraulic pressure, including not only elastic reservoir containers, but also structures consisting of spring-loaded pistons and equivalent devices mounted within rigid and semi-rigid reservoir containers, including containers having springs embedded within, or affixed to, flexible materials. In fact, a spring-loaded reservoir would represent a viable alternative that would also represent a less expensive component. Such structures, however, are well known by those skilled in the art and are not further described herein. 
     Several embodiments of this invention are now disclosed, each comprising a core group of interconnected components, and each further comprising a standard container  70 , an elastomeric bladder  60 , and an actuator assembly  20  using a flexible face fitment  24  in combination with a compression fitment  26  as seen in FIGS. 5-9 and  11 - 13  and as described above. 
     One embodiment, referred to as the double helix action (DHA) model, is illustrated in FIGS. 5-7. A second embodiment, referred to as the basic single helix action (basic SHA) model, is illustrated in FIGS. 8 and 9. Both models are comprised of essentially the same components, with minor variances in the geometries of the individual components. Both models specifically incorporate a piston head  57  and cylindrical housing  50 , as illustrated generally in FIGS. 7 and 9, that are each smaller in their respective diameters then those disclosed in previously patented dispensers, which allow the DHA and the basic SHA models to generate longer upward and downward bore strokes than those generated by previously patented dispensers. The longer bore strokes are critical to the efficiency of this invention. The longer strokes allow additional product initially to be hydraulically drawn into the cylindrical housing  50 , and subsequently forced into the elastomeric bladder  60 , thus ultimately allowing the product to be dispensed with a longer duration spray that that generated by previously patented dispensers. Further, the DHA and basic SHA models featuring piston heads  57  and cylindrical housings  50  with smaller diameters respectively, require the application of less force to overcome the frictional forces working against the downstroke of the piston  44 , thus making it easier for the user to operate the DHA and basic SHA models, and thus accommodating a wider range of users with otherwise limiting physical conditions, i.e., arthritis. 
     A third embodiment, illustrated in FIGS. 11-13 and referred to as a simplified SHA model, is manufactured using fewer components than basic SHA model, and it features a piston head  257  and cylindrical housing  250  with slightly larger diameters respectively than either the DHA model or the basic SHA model. In the simplified SHA model, the piston head  257  and cylindrical housing  250  have diameters of approximately 1.0 inch as compared to the piston head  57  and the piston housing  50  of the previous two models that have diameters measuring approximately 0.782 inches. This increase in diameter of each component  250 ,  257 , while simultaneously leaving the size and space of the threads of the spindle  46 ,  146  and the grooves of the piston collar cap  48 ,  148  unchanged, leaves the length of the piston  44  and the length of the cylindrical housing  50  unchanged. By making this slight modification, the simplified SHA model is able to increase the amount of product ultimately charged in the elastomeric reservoir  60 , thus increasing the duration of the product spray upon activation. 
     Further, while the increase in the size of the piston head  257  requires a user to apply more force to overcome the frictional forces working against the downstroke of the piston  244 , the simplified SHA model only requires one turn of its actuator housing  222  to fully charge the elastomeric reservoir  60  versus the 1¾ turns required of the actuator housings  22 ,  122  for both of the smaller head  57  models illustrated in FIGS. 7 and 9. In all three embodiments, the disclosed diameters of the respective pistons heads  57 ,  257  and cylindrical housings  50 ,  250  are exemplary for purposes of illustration. Those persons skilled in the art will appreciate that by simply changing the relative diameter sizes of the piston heads  57 ,  257  and the cylindrical housings  50 ,  250 , the amount of product hydraulically withdrawn from the container  70  and forced into the elastomeric reservoir  60  will be varied accordingly. Alternately, changes in the relative pitch of the threads of the spindle  46 ,  146  and the grooves of the piston collar cap  48 ,  148  and/or changes in the relative length of the piston  44  or the cylindrical housing  50 , will likewise vary the ultimate product output as those persons skilled in the art will appreciate and as will be discussed in more detail below. 
     Both the DHA model shown in FIGS. 5-7 and the SHA model shown in FIGS. 8 and 9 are comprised of the following common components: an actuator housing  22 , a flexible face fitment  24 , a compression fitment  26 , a turbo-actuator  28  (otherwise referred to as a MBU), a valve stem seal  30 , a spring valve retainer  32 , a collar cap  42 ,  142 , a piston  44 , a spindle  46 ,  146 , a piston collar  48 ,  148 , a cylindrical housing  50 , a reservoir bladder  60 , and an overcap  80 . The actuator assembly  20 ,  120  as shown in the embodiments illustrated in FIGS. 7 and 9, generally comprises the actuator housing  22 ,  122 , the flexible face fitment  24 , the compression fitment  26 , the turbo-actuator  28 , the valve stem seal  30 , and the spring valve retainer  32 . For a detailed summary of the structural composition of, and the mechanical operation of the actuator assembly, U.S. patent application Ser. No. 09/748,730, filed on Dec. 26, 2000, is attached hereto in its entirety and is incorporated expressly herein by reference. The actuator assembly therein disclosed by Blake is representative of the actuator assemblies incorporated in each of the disclosed embodiments of the present invention. Such an actuator assembly creates a discharge pathway through which product is dispensed, such that the flexible face fitment flexes away from two shutoff mating surfaces at a predetermined minimum pressure and then flexes back into sealing contact with the two shutoff mating surfaces when the product pressure drops below this minimum pressure. This results in a product that is dispensed in a fairly constant pattern that then shuts off abruptly, allowing negligible product dribbling as the pressure decreases and minimal product build-up behind the valve. 
     Referring to FIG. 9 for general purposes of illustration and FIG. 10 specifically, one novel feature of this invention that is common to all three models is the introduction of a valving mechanism  34 , comprised of the valve stem seal  30  and the spring valve retainer  32 , upon which the atomizing turbo actuator  28  sits. Once the reservoir bladder  60  has been charged up to the desired capacity, the valving mechanism  34  stands ready to be activated, which occurs when the button  29  on the turbo actuator  28  is depressed, thus allowing the contents of the reservoir  60  to discharge. The two components  30 ,  32  of the new valving mechanism  34  essentially replace five components that have been standard in most other previously disclosed aerosol valves. Common to the prior designs, stem valves just rested within the spring valve retainers while the actuators were locked or retained into position to inhibit the valve action via two wings at the base edge, which retained the assembly by snapping into windows molded into the upper body structure. The new valving mechanism  34  eliminates these unnecessary retention means by virtue of the geometry of the valve stem seal  30 , which has a bulbous contoured tip  33  that flexes into a pocket within the spring valve retainer  32 , thus seating itself so as to be permanently retained. Further assisting with the retention of the valve stem seal  30  within the spring valve retainer  32  is the leaf spring  35  that flexes upon the downward pressure of, and engages the outer lip  37  of, the valve stem seal  30 . 
     Referring to FIGS. 7,  9  and  11 , the actuator housings  22 ,  122 ,  222  and the collar caps  42 ,  142 ,  242  of the three disclosed models form the pressurizing mechanism of this dispenser system  10 . Components  22 ,  122 ,  222 , and  42 ,  142 ,  242  are each essentially circular in shape, and along with the rest of the components of the dispenser system  10  (with the exceptions of the flexible face fitment  24  and the compression fitment  26 ), are positioned symmetrically around a common vertical axis. Actuator housings  22 ,  122 ,  222  and the collar caps  42 ,  142 ,  242  also each feature an alternating grooved surface upon their respective circular outer walls  21 ,  121 ,  221 , and  41 ,  141 ,  241  so as to facilitate a non-slipping grip by the consumer. The pressurizing mechanism is activated when a system user grips the outer wall  21 ,  121 ,  221  of the actuator housing  22 ,  122 ,  222  with one hand, grips the outer wall  41 ,  141 ,  241  of the collar cap  42 ,  142 ,  242  or alternatively, the container  70  with the other hand, and proceeds to twist the actuator housing  22 ,  122 ,  222  counter-clockwise while simultaneously holding the collar cap  42 ,  142 ,  242  or the container  70  motionless. In each of the three disclosed models, the twisting steps are the same, i.e., the actuator housing  22 ,  122 ,  222  action is reversed, that is, it is twisted clockwise while the collar cap  42 ,  142 ,  242  or the container  70  is held stationary in order to complete the pressurizing or priming of the dispenser system  10 . 
     In each of the three disclosed models, and illustrated in FIGS. 7,  9  and  11 , an inset upper lip  81  of the actuator housing  22 ,  122 ,  222  creates an engaging means by which overcap  80  is seated to protect the activating button  29  from accidental discharge while the system  10  is in storage or while it is in transit. Such engaging means can be any of a wide variety of mechanical features that allows the overcap  80  to be securely fastened to the actuator housing  22 ,  122 ,  222  and yet also easily removed for operation of the dispenser system  10 . Such engaging means are well known to those persons skilled in the arts and will not be further discussed herein. 
     Referring specifically to FIGS. 5-7, the actuator housing  122  of the DHA model has an inner circular wall  123  that defines a space within its circumference through which the spring valve retainer  32  portion of the actuator assembly  120  is seated. The space within the circumference of the inner circular wall  123  is defined by the diameter that is slightly larger than the diameter of the spring valve retainer  32 , such that there is minimal clearance between the two components  123 ,  32  that creates a minimal frictional force between the two components  123 ,  32  upon operation of the system  10 . Between the grooved outer circular wall  121  and the inner circular wall  123  of the actuator housing  122 , there is an intermediate circular wall  125 , extending below the outer wall  121  in length, but not extending below the length of the inner wall  123 . The intermediate wall  125  is threaded, a feature which gives rise to the “double” helix action observed during the enactment of the pressurizing mechanism as will be further described below. 
     In each of the three models disclosed, the pressurizing mechanism is engaged initially by a first action generated by the upstroke of the piston  44 , as shown generally in FIG.  6 . As particularly shown in the figures, the first action occurs when a user applies an external rotating force that twists the actuator housing  122 , engaging grooves  124  of inner circular wall  123  with ribs  147  of spindle  146 , thereby providing rotation of spindle  146 . Correspondingly, when a user applies an external rotating force that twists the actuator housing  122 , threads  126  of intermediate wall  125  engage lugs  58  of outer circular wall  51  of housing  50 . In some embodiments, lugs  58  may comprise bayonet lugs, ramp lugs, or the like. The engagement and configuration of the threads  126  and the lugs  58  provide for an upward motion of the actuator housing  122  when the actuator housing  122  is twisted or rotated in a direction. Further, lugs  127  of piston collar  148  engage with one or more elements of cylindrical housing  50 , such as windows, and the lugs  128  of piston collar  148  engage with threads  145  of spindle  146 , providing an upward motion of spindle  146  and linear travel of piston  44  upon twisting the actuator housing in a direction. Therefore, piston  44 , which is connected to the spindle  146 , will linearly travel during the upstroke of the piston  44  and spindle  146 . As the spindle  146  and piston  44  withdraw from the cylindrical housing  50  during the course of the first action, product is pulled out of the container  70  through the dip tube acceptor port  54  and is deposited within the cylindrical housing  50 . The second action commences with the counter-directional twisting of the actuator housing  122  and a corresponding rotation of inner circular wall  123  and spindle  146 , a downward motion of actuator housing  122 , and a downward motion and linear travel of spindle  146  and piston  44 , provided by the mechanical relationships described above. As the spindle  146  and the attached piston  44  travel downward, the product is forced out of the cylindrical housing  50  and into the elastomeric bladder  60 , thus priming the dispenser system  10  prior to the activating button  29  being depressed. As will be recognized by persons skilled in the art, the quantity and type of product dispensed by such a system  10  can be varied by changing either the spacing between and/or pitch of the threads of the spindle  146  and the lugs of the interfacing piston collar  148 . 
     Continuing to refer generally to FIG. 7, similar changes can also be made with respect to the distance between and the pitch of the threads on the intermediate wall  125  of the actuator housing  122 . Further, by altering the spacing and pitch of the threads of the spindle  146  and the lugs of the interfacing piston collar  148 , as well as the internal threads of the actuator housing  122  and lugs  58  of outer circular wall  51 , products of various viscosities, surface tensions, formulations, etc. can be selected for a variety of specific applications. These variations will be discussed in greater detail below in reference to SHA embodiments. In this particular embodiment, the double helix action described above results in the deposition of the maximum amount of product within the elastomeric reservoir  60  as well as the maximum amount of product ultimately dispensed. 
     By contrast, FIG. 9 shows that the intermediate wall  25  of the basic SHA model is essentially smooth and is shaped such that it accepts the upper inner wall  43  of the collar cap  42  so as to more effectively facilitate the counter-directional twisting of the actuator housing  22  and the collar cap  42  during the pressurizing step, while also providing a significant degree of registration between the two components  22 ,  42 . In both the DHA model and the basic SHA model, the twisting of the actuator housing  122 ,  22  forces the spindle  146 ,  46  which is attached to the piston  44 , to travel via its threads either upward or downward along the grooves of the piston collar  148 ,  48  and/or along the grooves of the intermediate circular wall  125 , thus mechanically providing the force necessary to withdraw product from the container  70 , deposit it first within the cylindrical housing  50  and then ultimately within the elastomeric reservoir  60  to complete the charging of the dispenser system  10 . The mechanical advantage to these embodiments, referred to generally as a floating track and rail system design is that, with minimal effort, a single twist of the two components of DHA model (or 1¾ turns of basic SHA model, which would require the application of even less force by the user) generates a substantially long bore stroke, which translates into the acquisition of a large volume of product, which is then ready to be dispensed. This large volume of product is then capable of being sprayed consistently for a long period of time, i.e., 12-15 seconds, before the mechanical charge built up in the system  10  dissipates. In combination with the non-clogging flexible face actuator assembly&#39;s precise shut-off capability, this translates into a mechanical aerosol dispenser that has dispensing qualities comparable to those historically only found in chemical aerosol dispensers. 
     Referring again to FIG. 9, the upper inner wall  43  of the collar cap  42  of the basic SHA model is essentially smooth and further includes an inner circular rim  45  formed within the interior of the cap  42  that provides the structure against which the cylindrical housing  50  seats. The collar cap  42  also provides a lower inner circular wall  47 , slightly outset from the upper inner wall  43  that has threads upon its interior surface such that the collar cap  42  can be threadably connected with the standard container  70  housing the desired product. 
     Continuing to view FIG. 9, the outer circular wall  51  of the cylindrical housing  50  of the basic SHA model defines an annular space at its top that has a diameter large enough to accept the piston  44 , the piston collar  42 , and the spindle  46 . The circular bottom  53  of the cylindrical housing  50  extends radially inward from the outer circular wall  51 . It is not a solid bottom, however, and the inner circular edge  55  of the bottom  53  defines an inner space through which the reservoir bladder  60  protrudes and upon which the piston  44  comes to a final resting position. The cylindrical housing  50  includes several windows  52  that allow for a snap fit connection to the several corresponding lugs  49  of the piston collar  48 , provided in some embodiments as wing lugs, so that the piston  44  and spindle  46  are able to move securely up and down within the cylindrical housing  50  along the lugs  128  of the piston collar  48 , similar to the travel means described for the DNA model above. 
     The cylindrical housing  50  illustrated in FIG. 9, further includes a dip tube acceptor port  54  protruding from its bottom as well as a bleed back feature  56 , located in this embodiment, approximately 180° away, i.e., substantially opposite from the dip tube acceptor port  54 . The acceptor port  54  allows a dip tube (not shown) to be attached that provides a product pathway from the standard container  70  up into the cylindrical housing  50 , from where it then travels up through the actuator assembly  20  during the dispensing cycle. The bleed back feature  56  allows an overcharged reservoir bulb  60  to release some product back into the standard container  70 , thus reducing the pressure during the storage of the charge. In this embodiment, the bleed back feature  56  is conical in shape with the apex of the cone consisting of a webbing that, when pierced in the manufacturing process, forms the pathway for fluid to travel from the bulb  60  to the container  70 . Those persons skilled in the art will recognize that the geometry of the bleed back feature  56  controls the fluid&#39;s drop size and the rate at which the drops travel back to the container  70 . A wide range of geometrical shapes and sizes of bleed back features  56  can be selected depending on the objectives of each system and the type (i.e., viscosity, formulation, etc.) of product utilized. 
     FIG. 9 further illustrates the piston  44  itself as a narrow tube seated upon a circular head  57  that is raised up along with the spindle  46  within the cylindrical housing  50  upon the initial counter-directional twisting of the actuator housing  22  and the collar cap  42 , and forced back down into the cylindrical housing  50  until it rests upon the cylindrical housing bottom  53  upon the reverse counter-directional twisting of the two components  22 ,  42 . The up and down motion of the piston  44  within the cylindrical housing  50  provides the mechanical force needed to pull product from the standard container  70  up into the cylindrical housing  50  as described above. From the cylindrical housing  50 , the product is forced into the elastomeric bladder  60  upon the downstroke of the piston  44 . When the activating button  29  is depressed, the product is dispensed up through the actuator assembly  20 . As described above, the piston  44 , connected to the spindle  46 , travels up and down within the cylindrical housing  50  due to the twisting of the collar cap  42  which engages the threaded outer wall of the spindle  46 , that is connectedly joined to the collar cap  42  through the snap fitting of the piston collar  48 . This action provides for an upward motion of the piston  44  and spindle  46  in the first directional instance, and a downward motion of the piston  44  and spindle  46  in the second, reversible directional instance. 
     Continuing to refer to FIGS. 8 and 9, the lip  61  of the reservoir bladder of the basic SHA model is seated within an upstanding wall  57  extending radially upward from the bottom  53  of the cylindrical housing  50  while the rest of the reservoir bladder  60  protrudes through the inner annular space defined by the inner circular edge  55  of the bottom  53  of the cylindrical housing  50  extending down into the standard container  70 . As described above, upon the downward motion of the piston  44  and spindle  46 , the reservoir bladder  60  becomes charged with a hydraulic pressure differential created within the cylindrical housing  50 . Upon the release of the pressure through the depressing of the activating button  29 , the reservoir bladder  60  is discharged and the equilization of the hydraulic pressure differential within the cylindrical housing  50  allows any excess product to be dispensed within the standard container  70 . On the upward stroke of the piston  44 , product travels through the port acceptor  54  and into the cylindrical housing  50  where it awaits dispensing. The overcap  80 , which seats itself over an inset outer retaining wall  81  extending above the actuator housing  22 , serves solely to protect the actuator housing  22  from accidental discharge prior to use. 
     Thus with the exception of the geometries of the respective actuator housings  22 ,  122 , the piston collars  48 ,  148 , and the spline patterns on the spindles  46 ,  146 , the basic SHA model and the DHA model, as illustrated in FIGS. 5-7 and  8 - 9 , generally comprise the same components in combinations that are described above. The advantages created by the two embodiments include the abilities of both to obtain long bore strokes versus the strokes of previously disclosed dispensers. Further, the DHA model, as shown in FIGS. 5-7, exhibits an additional mechanical advantage due to the spline-to-rib engagement via two modes that simultaneously move the mechanism down with one twist/turn on the actuator housing  122 , utilizing a back and forth radial motion that produces twice the travel of the piston  44  and spindle  146  within the cylindrical housing  50 , thus more readily facilitating the hydraulic charging of the reservoir bladder  60 . While the stroke takes place, the actuator housing  122  moves upwards by one-half of the entire stroke. 
     By contrast, the basic SHA model, shown in FIGS. 8-9, features the same diameter piston  44  and spindle  46  combination that are used in the DHA model, but is differentiated by the reduction by one-half stroke when the upper mode of travel is removed, thereby forcing the lower mode to provide the remaining travel for the other half of the required stroke. Regarding other geometrical and functional aspects, however, the two embodiments are essentially similar. 
     A third embodiment, referred to as the simplified SHA model, features a slightly larger diameter piston  244 , is illustrated in FIGS. 11,  12  and  13 . One difference between this embodiment and the DHA model and the basic SHA model, is that it features less components and thus creates a simpler product to manufacture. In the simplified SHA model, the piston head  257  as shown has an approximately 1.0 inch diameter versus the approximately 0.782 inch diameter represented by the piston head  57  in the previous two embodiments. Again, it is important to note that the diameter specified is not intended to be limiting in any way; rather, the relative proportionality of the piston head  57 ,  257  and cylindrical housing  50 , 250  and/or the relative proportionality of the threads of the spindle or piston  46 ,  146 ,  244  and the grooves of the piston collar cap  48 ,  148 ,  245  and/or the length of the piston  44 ,  144 ,  244  and the length of the cylindrical housing  50 ,  250  are more important, as the proportional increasing or decreasing of the sizing of these components will accommodate a variety of product applications as will be readily appreciated by those persons skilled in the art. 
     In particular, the simplified SHA model features combining several of the individual components from the previously described embodiments during the manufacturing process, while retaining the primary function and the beneficial features of the general dispenser system  10 . Referring to FIG. 11, the piston  44  and spindle  146 ,  46  of both the DHA model and basic SHA model are replaced by a single component referred to as a threaded piston  224 . Similarly, the piston collar  148 ,  48  and the collar cap  142 ,  42  of the DHA model and of the basic SHA model have been replaced by a single component referred to as the threaded collar cap  242 . 
     Continuing to view FIG. 11, although both threaded collar cap  242  and actuator housing  222  have been geometrically modified relative to their DHA model and basic SHA model counterparts, there are many similarities between the three models. The threaded collar cap  242  and the actuator housing  222  of simplified SHA model still feature the alternating grooved surfaces of their respective circular outer walls to facilitate a non-slipping grip by the user. Thus, the pressurizing mechanism remains the same as in the two previously disclosed embodiments. Further, the threaded collar cap  242  retains the internal threading required to threadably connect with the standard container  70  housing the desired product. 
     FIG. 11 also illustrates that one of the few geometrical differences between the three models is that the newly constructed actuator housing  222  features only an outer circular wall  221  and an inner circular wall  223 . The space defined within the inner circular wall  223  still accepts the spring valve retainer  32  as it does in the DHA model and the basic SHA model, which itself accepts the valve stem seal  30  (comparable to the other two models as seen in FIGS.  7  and  9 ). The threaded piston  244  travels up the internal threading of the lower inner circular wall  245  of the threaded collar cap  242 . The lower inner circular wall  245  of the threaded collar cap  242  acts essentially as the threaded collar cap  48 ,  148  of the basic SHA model and the DHA model respectively, extending beneath the outer circular wall  241 . Further, the threaded collar cap  242  features an upper inner circular wall  243 , similar to the upper inner circular wall  43  of the basic SHA model, that seats within the annular space formed between the outer circular wall  221  and the inner circular wall  223  of the actuator housing  222 . Finally, the geometry of the cylindrical housing  250  of the simplified SHA model is different from the cylindrical housing  50  of both the basic SHA model and the DHA model. Instead of comprising windows  52  with which to engage the lugs  49  of the threaded collar  48  of the basic SHA model, it features an essentially smooth outer circular wall  251  with a retaining lip  259  encircling its upper end that provides a registration means by which to attach to the threaded collar cap  242 . 
     In respect of several components of the SHA model, the dispenser system  10  may be considered to be more simple both in operation and in manufacture. Futhermore, a venting means is disclosed. While all three embodiments include a venting system—it is required because the dispensing system  10  is considered open, wherein ambient air needs to be replaced when product is dispensed during the replenishing cycle of the dispensing sequence in order to offset the vacuum conditions created during the hydraulic priming. The venting system incorporated in the simplified SHA model is the most efficient. Referring to FIGS. 12,  13  and  14 , the venting means include a pair of vent holes  290 , located approximately 180° apart, and a pair of helix chambers, an upper helix chamber  292  and a lower helix chamber  294 . Functionally, when the vent holes  290  are open, i.e., when the threaded piston is at the apex of its downstroke, ambient air is allowed to enter the dispenser system  10  thus establishing an offset to the vacuum conditions created by the hydraulic priming and recreate an equilibrium condition within the system  10 . The ambient air enters the upper helix chambers  292  and carries through the window-to-latch configuration interface between the threaded collar cap  242  and the cylindrical housing  250 . Ambient air is also exchanged between the helix threads  296  of the interface between the cylindrical housing  250  and the lower circular inner wall  245  of the threaded collar cap  242  as the threads of the threaded piston  244  travel up and down the internal threads of the lower inner circular wall  245  of the threaded collar cap  242 . This telescoping action of the helix threads  296  with the air exchange feature, facilitates the system&#39;s functioning attributes to aid in maintaining a pressure equilibrium within the container  70  relative to the ambient environment outside, and at the same time, allows air exchange throughout the dispensing stroke as well as the replenishing stroke. 
     Continuing to refer to FIGS. 12,  13  and  14 , the two above-discussed situations occur only through the opening of the vent holes  290 , which occurs within every approximate 90° rotation during the telescoping action described above. In each cycle, there is only a full turn forward and backward that delivers approximately 15 seconds duration of spray with the vents holes  290  being open or closed throughout this cycle. Thus, the system  10  remains in a sealed “vents closed” position during the period in which the threaded piston  244  is fully retracted. For this reason, the system  10  will be assembled to the container  70  in a mode where the piston is fully extended and shipped to the user as a sealed container in this same configuration. 
     The foregoing description is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those persons skilled in the art, it is not desired to limit the invention to the exact construction and process shown as described above. Accordingly, all suitable modifications and equivalents may be resorted to falling within the scope of the invention as defined by the claims which follow. 
     The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

Technology Classification (CPC): 1