Abstract:
The present invention provides improved devices, components, and conduit assemblies for delivery of a breathable/inhalable fluid stream containing a solvation-enhancing atomized liquid, the fluid stream carrying a functional liquid component. In one aspect, devices of the invention incorporate an exchangeable fluid-permeable body, such as a cartridge comprising a fluid-permeable packing material, containing the functional liquid. In another aspect, devices of the invention incorporate an electronic control system configured to detect and store physical states, settings, modes/configurations, and/or usage of the device over time. Optionally, the detected states may be exported to a separate electronic device via a Wi-Fi or other suitable remote connection. In other embodiments, the electronic control system provides passcode authorization for actuating an atomizing element and/or toggling the device between locked and unlocked states.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 14/203,560, filed Mar. 11, 2014, the entire disclosure of which is hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to electronic cigarettes and more specifically to a configuration for introduction of chemical species into an atomized fluid airstream provided thereby. 
       BACKGROUND OF THE INVENTION 
       [0003]    In the use of electronic cigarettes, users often prefer an atomized liquid that is flavored and or combined with physiologically active chemicals, such as nicotine, over one that is not. Prior art achieves the delivery of such a fluid by way of an atomizing a mixture of propylene glycol, vegetable glycerin, or other suitable chemicals that are mixed with chemical species that provide a flavor or physiological effect, or both simultaneously. 
         [0004]    There are several shortcomings of the prior art that utilizes this approach. In prior art utilizing a tank for storage of the liquid for atomization, the tank volumes are often relatively large. Given that users often prefer to fill a tank with a large volume of liquid, it is inconvenient in the sense that a user must completely consume the liquid or must remove the liquid manually and replace it with a different liquid if they desire a different mixture. Furthermore, since it is difficult to completely remove a previous mixture from the internal components of a tank and atomizing apparatus, the mixtures can interact and create combinations that may be undesirable. Therefore an improvement upon prior art would be to make it more convenient for a user to exchange the flavoring or physiological active species with ease and without mixing of previously loaded mixtures. 
         [0005]    Additionally, prior art utilizing a heating element for atomization of a said mixture present the possibility of degradation and pyrolysis of chemical species residing in the mixture. Therefore there exists a need to improve upon the prior art so as to create a system whereby the chemical species desired for consumption of the user may not undergo excessive pyrolysis or degradation. 
       SUMMARY OF THE INVENTION 
       [0006]    According to one aspect of the present invention, breathable fluid delivery device (or inhalation device) components are presented. In one aspect, the disclosure presents an auxiliary conduit attachment for coupling with electronic cigarettes whereby chemical species can be introduced into a fluid stream provided by a coupled parent electronic cigarette or apparatus capable of forming such a fluid stream as described herein. 
         [0007]    According to another aspect of the present invention, a complete inhalation device, such as an electronic cigarette device, for delivery of atomized liquid and other functional chemical species is provided. The device is preferably a handheld assembly of components including a battery assembly, an electronic control circuit, at least one atomizing element, and a series of fluid conduits. The atomizing element may comprise any suitable mechanism for atomizing a liquid to be introduced into a breathable (generally interchangeable with “inhalable” for purposes of this description and claims) fluid stream. 
         [0008]    The fluid conduits include an atomization liquid storage chamber, an atomization chamber, a suitable exchangeable fluid-permeable body, illustrated and described herein as a “cartridge” comprising a porous packing material for containing a functional liquid, and a mouthpiece. Cartridges generally referred to herein include a casing for containing the porous packing material, which is desirable for retaining functional liquid within the cartridge and/or imparting a shape to certain packing materials. However, if the packing material is a solid, stiff, unitary mass, which may be termed a “pod” in the context of the invention, the casing is not essential to hold the shape of the pod, and may optionally be omitted despite the possible increased tendency of leaking or evaporation of functional liquid therefrom. In some embodiments, the device includes an atomizing element associated with the cartridge itself, to atomize and facilitate the introduction of the functional liquid contained in the cartridge into the breathable fluid stream, either in lieu of or in addition to an atomizer tank assembly connected in line with the cartridge. 
         [0009]    The device further includes electronic components such as a battery, an electronic controller for directing a controlled voltage and current to other electronic components, a user display and/or input interface, a signal receiver component, electrically powered atomizing elements, a button/switch/other manual actuator, and conductive wires or other circuit elements. The electronic controller may include a processor, a memory, and/or one or more sensors, which enable the device to perform functions such as storing, recalling, and presenting to a user historical device state data or usage data, adjusting current or voltage in response to detected overheating of components or other predetermined device states, automatically actuating atomizing elements in response to sensing a user drawing breath from a mouthpiece, and actuating or “unlocking” atomizing elements in response to a passcode input. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a transverse plan view of an inhalation device attachment in accordance with an aspect of the invention. 
           [0011]      FIG. 2  is a transverse cross-sectional view of the attachment shown in  FIG. 1 . 
           [0012]      FIG. 3  is an exploded view of the attachment shown in  FIG. 1 . 
           [0013]      FIG. 4  is an exploded cross-sectional view of the attachment shown in  FIG. 1 . 
           [0014]      FIG. 5  is a transverse cross-sectional view of a fluid-permeable cartridge according to another aspect of the invention. 
           [0015]      FIG. 6  is an end view of a fluid permeable end of the cartridge shown in FIG. 
           [0016]      FIG. 7  is an exploded cross-sectional transverse view of the cartridge shown in  FIG. 5   
           [0017]      FIG. 8   a  is a transverse cross-sectional view of another attachment according to the invention, showing a valve in a closed position. 
           [0018]      FIG. 8   b  is a transverse cross-sectional view of the attachment shown in  FIG. 8   a , showing the valve in a partially open position. 
           [0019]      FIG. 8   c  is a transverse cross-sectional view of the attachment shown in  FIG. 8   a , showing the valve in a fully open position. 
           [0020]      FIG. 9  is a transverse plan view of the attachment shown in  FIG. 8   a.    
           [0021]      FIG. 10  is an exploded perspective view of the attachment shown in  FIG. 8   a.    
           [0022]      FIG. 11  is a transverse cross-sectional view of another attachment according to the invention. 
           [0023]      FIG. 12   a  is a transverse plan view of another attachment according to the invention. 
           [0024]      FIG. 12   b  is a transverse cross-sectional view of the attachment shown in  FIG. 12   a    
           [0025]      FIG. 13  is a distal end view of an alternative cartridge housing and an alternative cartridge housing cover section of the attachment shown in  FIG. 12   a    
           [0026]      FIG. 14  is a transverse view of an alternative coupling adaptor component of the attachment shown in  FIG. 12   a , including an integral valve needle. 
           [0027]      FIG. 15   a  is a proximal end view of a distal cartridge housing cover section of the attachment shown in  FIG. 12   a.    
           [0028]      FIG. 15   b  is a cross-sectional proximal perspective view of the distal cartridge housing cover section shown in  FIG. 15   a.    
           [0029]      FIG. 16   a  is a transverse cross-sectional view of an integrated cartridge and valve seat of the attachment shown in  FIG. 12   a.    
           [0030]      FIG. 16   b  is a transverse cross-sectional view of an alternative integrated cartridge and valve seat for use in the attachment shown in  FIG. 12   a.    
           [0031]      FIG. 16   c  is an exploded perspective view of the integrated cartridge and valve seat depicted in  FIG. 16   b.    
           [0032]      FIG. 17   a  is a distal end view of an alternative valve needle and coupling adaptor component accommodating a clicker element. 
           [0033]      FIG. 17   b  is a transverse cross-sectional view of the alternative valve needle and coupling adaptor component accommodating a clicker element shown in  FIG. 17   a.    
           [0034]      FIG. 17   c  is a distal perspective view of the alternative valve needle and coupling adaptor component accommodating a clicker element shown in  FIG. 17   a.    
           [0035]      FIG. 18  is an exploded proximal perspective view of a valve assembly including the alternative valve needle and coupling adaptor component accommodating a clicker element shown in  FIG. 17   a.    
           [0036]      FIG. 19  is a transverse exploded plan view of a complete inhalation device incorporating a fluid permeable cartridge and variable valve system in accordance with an aspect of the invention. 
           [0037]      FIG. 20  is a transverse view of another embodiment of a complete inhalation device. 
           [0038]      FIG. 21  is an exploded view of the inhalation device shown in  FIG. 20 . 
           [0039]      FIG. 22  is a transverse cross-sectional view of the inhalation device shown in  FIG. 20 . 
           [0040]      FIG. 23  is a fragmentary transverse cross-sectional view of the inhalation device shown in  FIG. 20 , illustrating an atomizer tank assembly thereof. 
           [0041]      FIG. 24  is a fragmentary transverse cross-sectional view of the inhalation device shown in  FIG. 20 , illustrating the relationship between a cartridge component and an atomizer tank assembly thereof. 
           [0042]      FIG. 25  is a transverse cross-sectional view of another alternative inhalation device. 
           [0043]      FIG. 26  is a fragmentary transverse cross-sectional view of the inhalation device shown in  FIG. 25 , illustrating a snap-locking throttle valve assembly thereof. 
           [0044]      FIG. 27  is fragmentary transverse cross-sectional view of another alternative inhalation device, illustrating a threaded, snap-locking throttle valve assembly thereof. 
           [0045]      FIG. 28  is an exploded view of an entire inhalation device incorporating the throttle valve assembly illustrated in  FIG. 27   
           [0046]      FIG. 29  is a transverse cross-sectional view of an exchangeable fluid-permeable cartridge according to an aspect of the invention. 
           [0047]      FIG. 30  is a transverse cross-sectional view of another exchangeable fluid-permeable cartridge according to an aspect of the invention. 
           [0048]      FIG. 31  is a transverse view of still another exchangeable fluid permeable cartridge according to an aspect of the invention. 
           [0049]      FIG. 32  is a transverse cross-sectional view of yet another exchangeable fluid permeable cartridge according to an aspect of the invention. 
           [0050]      FIG. 33  is a transverse cross-sectional view of still another exchangeable fluid permeable cartridge according to an aspect of the invention. 
           [0051]      FIG. 34  is transverse cross-sectional view of a battery/controller component according to another aspect of the invention. 
           [0052]      FIG. 35  is a fragmentary transverse cross-sectional view of the snap-locking throttle valve assembly shown in  FIG. 26 , showing the most open position in an adjustable range thereof and indicating illustrative fluid flow pathways. 
           [0053]      FIG. 36  is a fragmentary transverse cross-sectional view of a connection between a battery/controller component and an atomizer tank assembly according to an aspect of the invention, indicating illustrative breathable fluid inlet pathways into an inhalation device. 
           [0054]      FIG. 37  is an exploded view of the connection shown in  FIG. 36 . 
           [0055]      FIG. 38  is a fragmentary transverse cross-sectional view of an inhalation device incorporating stacked fluid-permeable pods in an exchangeable cartridge according to another aspect of the invention. 
           [0056]      FIG. 39  is an exploded perspective view of an exchangeable atomizer tank assembly according to another aspect of the invention. 
           [0057]      FIG. 40  is an exploded perspective view of an alternative exchangeable atomizer tank assembly according to another aspect of the invention. 
           [0058]      FIG. 41  is a transverse cross-sectional view of an exchangeable cartridge incorporating an atomizing element according to still another aspect of the invention. 
           [0059]      FIG. 42  is a transverse cross-sectional view of an exchangeable cartridge incorporating an atomizing element and a liquid reservoir according to yet another aspect of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0060]    Illustrative embodiments and exemplary applications will now be described with reference to the accompanying drawings to disclose the advantageous teachings of the present invention. 
         [0061]    In this disclosure, relational terms such as first and second, top and bottom, proximal and distal, upper and lower, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. In this disclosure, the use of the term “proximal” with relation to the anatomy of the present invention may be used to distinguish the end of the disclosed assembly that is at the farthest end of the mouthpiece, while the “distal” end refers to the farthest end of the battery enclosure. However, the relative positions and orientations of components or features of an inhalation device are described and depicted for illustrative purposes and are not required unless expressly stated. 
         [0062]    In this disclosure, the terms “fluid,” “fluid stream,” and “fluid flow” may refer to any suitable fluid composition, including but not limited to pure air or air mixed with an atomized, volatilized, nebulized, discharged, or otherwise gaseous phase or colloidal aerosol form of a functional liquid or atomizing liquid described herein. 
         [0063]    In this disclosure, the term “functional liquid” shall be understood to represent a chemical species, composition, or mixture thereof, which is intended to be volatilized, atomized, or otherwise introduced into a fluid stream that is in communication with said liquid. The functional liquid may be comprised of any single chemical species or combination of chemical species having desirable properties for enhancing an inhaled fluid stream and being suitable for adsorption upon or absorption into media suitable for use in the present invention. Furthermore, a functional substance in non-liquid form, which may for example be crystalline or otherwise solid, may be substituted for a functional liquid without departing from the scope of the invention. 
         [0064]    In this disclosure, the term “atomizing liquid” shall be understood to represent a chemical species, or mixture thereof, which is intended to be vaporized, nebulized, or otherwise introduced into and carried with a said fluid stream passing through the present invention. Furthermore, in extension of previous discussion, the atomizing liquid may emulate various physical characteristics of tobacco smoke upon atomization, such as a visible plume and/or the temperature, bulk, flavor, or other organoleptic qualities of the inhaled stream. Furthermore the atomizing liquid may also act to enhance the solvation characteristics of the fluid stream or act to deliver heat energy to another material or substance, such as through condensation. According to the present invention, the atomizing liquid may include propylene glycol or vegetable glycerin, for example. Transition of a chemical species from liquid form to a gaseous phase or nebulized phase is commonly facilitated by rapid heating on a resistive coil, or nebulization via a vibrating film, plate, or reed. It is to be appreciated that the present invention is not limited to utilization of the stated methods and/or chemicals, but may employ any suitable mechanism capable of transitioning a liquid into a gaseous or nebulized phase to be carried in a fluid stream providing the desired functions as stated or implied. 
         [0065]    The present invention relates to breathable fluid delivery apparatuses, such as electronic cigarettes and other inhalation devices, including an exchangeable fluid permeable cartridge containing a liquid mixture of chemical species to be introduced into a breathable fluid stream passing through the cartridge, which may comprise air in combination with atomized liquid, vapor, or both. With respect to the phrase “introduced into a breathable fluid stream,” one skilled in the art will understand the term “breathable” in a broad sense of being comfortable for a human user to inhale intermittently, as in the ordinary use of electronic cigarettes, vaping pens, and similar devices. In the context of the invention, the term “breathable fluid stream” includes but is by no means limited to pure air and substances similarly suitable for breathing continuously for extended time periods. The exchangeable fluid permeable cartridge may be disposed in an auxiliary conduit attachment substituting for the mouthpiece of an atomized liquid delivery system (such as an existing electronic cigarette). 
         [0066]    In particular, in accordance with an aspect of the present invention, an apparatus for delivering a functional liquid in a breathable fluid stream for inhalation is provided. The apparatus may be an attachment for a breathable fluid delivery device, comprising a mouthpiece, which may be removable, including a distal opening in fluid communication with a proximal opening; and a cartridge comprising a fluid-permeable packing material, configured for drawing a breathable fluid through the packing material by inhaling through the mouthpiece. The phrase “in fluid communication” will be understood to refer broadly to components or features of the device disposed in the path of a common fluid channel or conduit, without limitation to components that are necessarily directly adjacent to one another. 
         [0067]    The packing material contains a functional liquid disposed to be introduced into the fluid stream as the fluid stream passes through the packing material and to be carried in the fluid stream in a breathable form when the fluid stream passes out of the mouthpiece through the distal opening. The functional fluid may provide a flavor, a recreational and/or medicinal drug effect, or other desired effect when the breathable fluid stream is inhaled. 
         [0068]    A cartridge suitable for use with embodiments of the invention may consist solely of a fluid permeable packing, or may further comprise additional elements. For example, the cartridge may include a casing covering at least a portion of the packing. Where present, the casing may include open ends or fluid permeable ends that nonetheless provide support to prevent the packing from falling out of or being removed from the casing. Whether the casing includes open ends or fluid-permeable ends that support/retain the packing, the ends of the casing may be sealable for storage or shipping by a removably adhered film. The packing itself may also take different forms, including a single solid porous body or pod, or a mass of fibers, particles, or grains having spaces therebetween, functioning to permit fluid passage, similarly to the pores of a single porous body. 
         [0069]    The cartridge may be manually removably retained in a housing, which in turn may be retained supported, and/or enclosed by a housing cover. The cartridge housing includes a proximal opening in fluid communication with the breathable base fluid and a distal opening in fluid communication with the proximal mouthpiece opening, and the housing including structure to support the cartridge in a position in which a portion, such as a proximal end, of the cartridge is in fluid communication with the proximal housing opening and a portion, such as a distal end, of the cartridge is in fluid communication with the distal housing opening. The housing may be removably connected to a fluid delivery device, for example via a coupling adaptor, the fluid delivery device being configured to deliver a stream of the breathable base fluid into the proximal housing opening. Coupling adaptors according to the invention may or may not be interchangeable with existing mouthpieces of existing breathable fluid devices. 
         [0070]    When an apparatus according to the invention includes a cartridge housing cover, the housing cover may comprise two separate cover sections removably connected together to at least substantially surround the housing but for a proximal housing cover opening in fluid communication with the proximal housing opening and a distal housing cover opening in fluid communication with the distal housing opening. The two housing cover sections may be threaded together, or, for example, mated together by an insertable portion of one of the sections being slidingly inserted into a receiving portion of the other section. Whether slidingly mated or threaded together, the housing cover sections preferably comprise a resilient member disposed on at least one of the insertable portion and the receiving portion to seal the connection between the housing sections and to frictionally retain the housing sections in a mated configuration. 
         [0071]    Preferably, the apparatus or attachment includes a flow channel in which the packing is disposed, the flow channel including a wider portion adjacent at least one of the distal and the proximal end of the cartridge, and a narrower portion adjacent the wider portion and extending therefrom in a direction away from the cartridge. Advantageously, to maximize the surface area available for inflow of breathable fluid through the cartridge, a spacer feature abuts the cartridge to maintain an axial distance between the cartridge and the narrower channel portion. The spacer feature may comprise a separate annular member, or it may be integrated into, for example, a cartridge casing or housing. The spacer may have a uniform longitudinal dimension, or it may have a tapered dimension, so that no part of the proximal/upstream/inlet area of the cartridge is covered so as to block inflow of breathable fluid. 
         [0072]    In accordance with another aspect of the invention, a fluid-permeable cartridge for breathable delivery of a functional liquid is provided as a stand-alone product. The cartridge comprises a fluid-permeable packing material containing an absorbed or adsorbed quantity of a functional liquid configured to be introduced into a breathable fluid stream flowing through the cartridge. The cartridge may further include a fluid-impermeable covering disposed over at least a portion of the outer surface area of the packing material. Such a covering may comprise a wall structure generally surrounding the packing material, with or without one or two fluid-permeable ends joined to the wall structure to fully retain/cover/encase the packing. To facilitate shipping and/or extended storage, the covering may include a fluid-impermeable film material removably fixed over the ends of the covering to seal the packing material and functional liquid within the covering for storage and/or transport prior to use of the cartridge. Alternatively, the covering may also accept sealing caps that may be compressed onto the ends, such as plastic caps, which could act to seal the cartridge when it is not in use or in storage. 
         [0073]    Suitable film materials may include, without limitation, metal foil, BoPET (Biaxially-oriented polyethylene terephthalate), and plastics, and the film may be affixed by adhesive and/or heat-fused wax. Packing materials may be selected from among cotton, foam, fibrous media, stacked thread, stone, synthetic porous media, and any other materials having the desired adsorption/absorption and fluid permeability properties. 
         [0074]    In accordance with yet another aspect of the invention, a conduit assembly for a breathable fluid delivery device is provided. In particular, a fluid-permeable cartridge is disposed in a main fluid channel for inhalation delivery of a breathable fluid stream, the cartridge containing a functional liquid disposed to be introduced in a breathable form into a breathable base fluid flowing in the main fluid channel through the cartridge. A source of the breathable base fluid is connected in fluid communication with an upstream end of the cartridge—this may be any reservoir of or component or system for delivering a breathable base fluid, including but not limited to a fluid tank and a heating coil or vibration element, for example, where such a tank and atomizing element are sometimes collectively termed a “cartomizer.” A mouthpiece is connected in fluid communication with a downstream end of the cartridge, and an adjustable valve system is incorporated in the assembly for adjusting the flow impedance of a bypass channel passing around the cartridge relative to the flow impedance of a portion of the main channel extending through the cartridge. 
         [0075]    In a particular embodiment, the adjustable valve system comprises a tube in fluid communication with the breathable base fluid source, and a tube in fluid communication with the upstream end of the cartridge, one of the tubes being an insertable tube comprising a tapered tip narrowing to a smallest exterior cross section at an open end of the tube, at least a portion of the tapered tip being insertable into an open end of the other tube, the other tube being a receiving tube. The insertable and receiving tubes are relatively movable for insertion and withdrawal of the tapered tip into and out of the receiving tube to vary the cross-sectional area of a clearance between the receiving tube opening and the tapered tip. The bypass channel is in fluid communication with the breathable base fluid source only by way of a passage extending through a clearance between the receiving tube opening and the tapered tip. Preferably, the insertion tube includes a structural feature configured to seal off the receiving tube opening when fully inserted to a closed valve position, to cut off all flow through the bypass channel. 
         [0076]    In accordance with aspects of the present disclosure, breathable fluid delivery device components are presented. In one aspect, the disclosure presents an auxiliary conduit attachment for coupling with electronic cigarettes whereby chemical species can be introduced into a fluid stream provided by a coupled parent electronic cigarette or apparatus capable of forming such a fluid stream as described herein. 
         [0077]    In accordance with a first aspect of the present invention, with reference to an embodiment thereof illustrated in  FIGS. 1-4 , an auxiliary conduit attachment  10  for coupling with breathable fluid delivery devices such as electronic cigarettes will now be described. Attachment  10  may substitute for a mouthpiece of an existing fluid delivery device, and thus includes a coupling adaptor  12  for attaching to the fluid delivery device as would an existing mouthpiece. 
         [0078]    As shown in  FIG. 2 , a cartridge housing  14  and a coupling adaptor  12  fit together to retain and support between them an exchangeable fluid permeable cartridge  16 , capable of containing a functional liquid disposed to be readily picked up and carried in a breathable fluid stream passing therethrough. The proximal end of housing  14  may for example be threaded onto coupling adaptor  12 , or attached thereto in any other suitable manner. Housing  14  and adaptor  12  cooperate to provide a defined slot for cartridge  16  to rest in, to prevent cartridge  16  from easily sliding or falling out of housing  14  when being exchanged by a user. Additionally, the housing slot does not severely obstruct access to cartridge  16 , so as to make it relatively easy for a user to exchange cartridge  16  by grasping it with one&#39;s fingers. 
         [0079]    To permit the passage of a breathable fluid through attachment  10 , coupling adaptor  12  includes an open channel  18  spanning its internal length, which may or may not have a similar inner diameter to that of a mouthpiece for which attachment  10  substitutes, and housing  14  also includes a channel for receiving a mouthpiece  15 . In a preferred embodiment, the housing cover includes a distal end wall with a channel  19  passing through it designed to accept mouthpiece  15 . Alternatively, the housing cover may comprise an integrated mouthpiece (not shown). Various embodiments could adapt to various mouthpieces. In the illustrated embodiment, mouthpiece  15  has the same dimensions as coupling adaptor  12 . In other various embodiments, the dimension of the coupler and the dimension of the channel could vary and do not necessarily need to be compatible in terms of mouthpiece attachment male and female fittings. 
         [0080]    Attachment  10  may be constructed with various fluid delivery device coupling adaptors to permit use of attachment  10  with said devices at a connection point where a mouthpiece of an existing type would normally fit, although coupling adaptor  12  may alternatively comprise a different type of connector 
         [0081]    The proximal end of the slot for cartridge  16  includes a structural spacer feature, illustrated in  FIG. 2  as a stepped profile  20  of coupling adaptor  12 . The spacer feature acts to lift the exchangeable cartridge off of the proximal base of the housing slot where a fluid enters from an opening, illustrated as the distal end of channel  18 , having a cross-sectional area smaller than the area of an volume  22  defined by the riser of the stepped profile of coupling adaptor  12 . Thus, the spacer feature functions to increase the cross-sectional area where a breathable fluid stream may enter cartridge  16 . 
         [0082]    Cartridge  16  may comprise a casing  24 , fluid permeable ends  26  and  28 , and a fluid permeable packing  30 , which may for example be a single porous body or a mass of fibers, coarse grains, or particles of material including spaces therebetween, even if the individual fibers, grains, or particles are themselves non-porous. Casing  24  is preferably a tube-like structure having a hollow channel spanning its length and open ends. At the ends of casing  24 , fluid permeable ends  26  and  28  are connected or attached to allow the passage of a fluid through the casing channel and packing  30 , while providing containment of packing  30  inside casing  24 . Fluid permeable ends  26  and  28  may be, but are not limited to, mesh screens or perforated sheets having arrayed apertures  32 , as illustrated in  FIG. 6 . As an additional aspect, one or both of ends  26  and  28  may be constructed from the same piece of material as the casing  24 , but with fluid permeable properties. Ends  26  and  28  may be constructed to permit sealing with a thin film or the like (not shown) for storage and packaging of cartridge  16 . This film may for example be metal foil, plastic, or other comparable materials that could be fixed to ends  26  and  28  via an adhesive, heat fused wax, or other comparable method. 
         [0083]    Packing  30  may be composed of any suitable material that is fluid permeable and does not pose an inhalation health risk. Suitable materials for packing  30  include cotton, foam, stacked thread, porous stone, synthetic porous media, or any other material which is capable of adsorbing or absorbing the desired chemical species in liquid phase. Packing  30  is configured to accept a functional liquid, while still maintaining fluid permeable properties. In particular, packing  30  should be capable of holding a reasonable quantity of the functional liquid before becoming saturated, to avoid the need for frequent replacement of cartridge  16 . 
         [0084]    In certain preferred pairings of a packing material of packing  30  with a functional liquid, the surface chemistry of the packing material favors the adsorption of the functional liquid in order to improve saturation and functional liquid load. For example, a porous media having a surface chemistry that is hydrophilic may better saturate with hydrophilic functional liquids. A sintered porous plastic has proven to be a particularly effective porous medium, due to its tendency to force an air flow to spread generally evenly across its entire cross-sectional area, thereby exposing a greater volume of air to the functional liquid. This widening/dispersion of the air stream is believed to be largely due to a significant flow resistance produced by the material, as evidenced by a noticeable pressure drop across the length of cartridge  16  when packed and saturated. Other media may exhibit similar flow properties with similar effects. 
         [0085]    Functional liquids that may be advantageously contained in cartridges according to the invention include, without limitation, esters, acetate esters, alcohols, acids, lactones, carbonyls, terpenes, thiols, saturated and unsaturated thiosulfinates, hemiterpenes, monoterpenes, sesquiterpenes, diterpenes, sesterterpenes, triterpenes, sesquiterpenes, tetraterpenes, polyterpenes, norisoprenoids, and derivatives thereof, such as terpin hydrate, a derivative of turpentine; natural flavor compounds such as those often found in fruits, including but not limited to: Gamma Decalactone, Gamma Octalactone, Butyric Acid, 2-Methyl Butyric Acid, Proprionic Acid, Isovaleric Acid, Isobutyric Acid, Cinnamic Acid, Phenethyl Alcohol, Ethyl Butyrate, Ethyl Isobutyrate, Ethyl-2-Methyl Butyrate, Ethyl Isovalerate, Methyl Cinnamate, Ethyl Proprionate, Ethyl Hexanoate, Isoamyl Isovalerate, Phenethyl Acetate, (Z)-3-hexenal, beta-ionone, hexanal, beta-damascenone, 1-penten-3-one, 3-methylbutanal, (E)-2-hexanal, 2-isobutylthiazole, 1-nitrophenylethane, (E)-2-heptenal, furanones, 2,5-dimethyl-4-hydroxy-3(2H)-furanone, methyl 2-methylbutanoate, ethyl 2-methylpropanoate, methyl hexanoate, methyl butanoate, trans-2-hexenal, ethyle-2-methylbutanoate, ethyl butanoate, trans-2-hexenol, hexyl acetate, hexyl butanoate, 1-butanol, 1-hexanol, cis-3-hexenal, cis-3-hexeol, cis-3-hexenyl acetate, ethyl hexanoate, propyl 2-methylbutanoate, 2-methyl-1-butanol, benzyl alcohol, 1-octanol,2-phenylethanol, 1,3-oct-5(Z)-enediol, 1,3-octanediol, 4-vinylguaiacol, eugenol, 2-methylbutanoic acid, 4-hydroxyphenylacetic acid, 3-hydroxy-beta-damascone, 4 hydroxy-3-methoxyphenylacetic acid, 3-oxo-alpha-ionol, vomifoliol, 3-Oxo-β-ionol, dehydrovomifoliol, roseoside; and/or natural flavor compounds such as those found in vegetables, including but not limited to: dimethyl sulfide, thiosulfinates, disulfides, poly-sulfides, 2-propene-1-sulfinothioic acid S-2-propenyl ester (allicin), methanesulfinothioic acid S-2-propenyl ester, 2-propene-1-sulfinothioic acid S-(E,Z)-1-propenyl ester, 2-propene-1-sulfinothioic acid S-methyl ester, Linoleic acid, (E)-2-nonenol, (E)-2-nonenal, (Z)-3-nonenol, (Z)-3-nonenal, C9 Carbonyls, (Z,Z)-3,6-nonadienal, (E,Z)-2,6-nonadienal, 3-methylbutanoates, 2-phenethyl esters, 2-phenethyl 3-methylbutanoate, (E)-2-hexenyl 3-methylbutanoate, benzyle 3-methylbutanoate, (E)-2-hexenyl 3-methylbutanoate, benzyl 3-methylbutanoate, methyl 3-methylbutanoate, butyl 3-methylbutanoate, 3-methylbutanoate, butyl 3-methylbutanoate, 3-methylbutyl 3 methylbutanoate, (E)-2-pentenyl 3-methylbutanoate, 2-phenethyl hexanoate, sesqunterpene alcohol, cubenol, phthalides, 3-butylphthalides, 3-butuyl-4,5-dihydrophalide, cis and trans forms of 3-butyl-3a,4,5,6-tetrahydrophthalide, (Z)-ligustilide, 1-(E,Z)-3,5,-undecatriene, sesquinterpene hydrocarbons, alpha-copane, alpha-muurolene, alpha-calacorene, cadinenes, 2-acetyl-1-pyrroline, 2-ethyl-3,6-dimethylpyrazine, acetaldehyde, 3-methylbutanal, 4-vinylguaiacol, 2-acetylthiazole, 2-acetyl-2-thiazoline, 2-(1-hydroxyehtyl)-4,5-dihydrothiazole, 2,5-Dimethyl-4-hydroxy-3(2H)-furanone, hydrogen sulfide, methanethiol, ethanethiol, octa-1,5-dien-3-one, linolool, (E,E)-deca-2,4-dienal, p-mentha-1,3,4-triene, myrcene, 2-sec-butyl-3-methoxypyrazine, myristicin, (E,E)-deca-2,4-dienal, (Z)-dec-6-enal, Beta-phellandrene, (Z)-hex-3-enal, (Z)-hex-3-enol, (Z)-hex-3-enyl acetate, vanillin, menthol, methyl salicylate, 3,7-guaiadiene, delta-cadinene, cannabinoids, nicotine, caffeine, citicolene, and taurine. The current invention may also employ the vast array of melanoidins, a class of chemicals produced by Maillard reactions, wherein amino acids and reducing sugars are heated together to produce complex compositions of chemicals derived therefrom. In addition, extracts from plants and other biological materials may be utilized. Pharmaceutical inhalation delivery drugs may also be utilized, such as Cidesonide, Cromolyn Sodium, Ipratropium Bromide, Nedocromil Inhalation, Albuterol Sulfate, Triamcinolone Acetonide, Albuterol Sulfate, Levalbuterol Tartrate, Flunisolide Hemihydrate, Fluticasone Propionate, Salmeterol, Fluticasone Propionate, Paclitaxel, Salmeterol Xinafoate, Metaproterenol Sulfate, Beclomethasone Dipropionate HFA, Beclomethasone Dipropionate Monohydrate, Ribavirin, N-acetyl-L-cysteine, Loxapine, Insulin, Pirbuterol, Budesonide, Formoterol Fumarate Dihydrate, Methacholine Chloride, Mometasone Furoate, Pentamidine Isethionate, Domase alfa, Iloprost, Tobramycin, Fluticasone Propionate, Arformoterol Tartrate, Idarubicin, Levalbuterol. 
         [0086]    As an alternative to cartridge  16  as illustrated, a cartridge within the scope of the invention may consist of only an open ended casing and a fluid permeable packing material residing inside the casing, such as a porous body, a quantity of particulate material, or a mass of fibers. The embodiment may contain the packing partially or completely saturated with a said functional fluid and the cartridge as a whole may be exchangeable in the same fashion as that of the disclosed embodiment consisting of casing  24 , packing  30 , and fluid permeable ends  26 ,  28 . 
         [0087]    In another embodiment, the cartridge may consist solely of a packing material, which may not necessarily have an outer casing or fluid permeable ends. The porous material may be partially or completely saturated with a functional fluid and may be exchangeable in the same fashion as that of the disclosed embodiment having casing  24  and fluid permeable ends  26 ,  28 . 
         [0088]    Individual parts of attachments or fluid delivery devices according to the invention may be constructed out of any suitable material that permits ease of use thereof, durability, safety, and ease of manufacturing. In preferred embodiments, components are generally composed of a relatively hard, durable, and non-corrosive material, such as stainless steel, aluminum, brass, graphite, ceramics, silicon carbide, certain plastics or other suitable materials. Plastics used for components of an inhalation device according to the invention should generally be highly chemically resistant, as some functional fluids, such as certain alcohols, have been shown to cause degradation of certain existing plastic mouthpieces and polycarbonate parts. Suitable plastics may include silicones, thermoplastic elastomers/TPEs, Santoprene®, polytetrafluoroethylene (PTFE), polyaryletherketone family plastics, such as PEEK (polyether ether ketone), PVDF (polyvinylidene difluoride), PVC (polyvinyl chloride), CPVC (chlorinated polyvinyl chloride), Nylon®, Teflon®, HDPE (high density polyethylene), LDPE (low density polyethylene), Acetal, ABS (Acrylonitrile butadiene styrene), Halar®, Fluorosint®, Polypropylene, Polysulfone, PPS (polyphenylene sulfide), Torlon®, UHMW (ultra-high-molecular-weight polyethylene), CAB (cellulose acetate butyrate), Ertalyte®, Nylatron®, Acetron®, TIVAR®, Proteus®, and Sanalite®. 
         [0089]    In preferred embodiments, materials used do not pose a significant health risk to users under normal use conditions, and should be selected to be compatible with the functional fluids used. For example, some functional fluids suitable for use according to the invention, including alcohols and terpenes, are corrosive to certain materials that are otherwise desirable for use in the devices of the invention. Polycarbonate is an example of a clear, hard plastic that may be advantageously used for device components, so long as it is not exposed to certain functional fluids that may damage it. Coupling adaptor  12  may be coated in a protective coating such as a paint, powder coating, film coating, electroplated coating, or any other suitable coating compatible with the material of construction. 
         [0090]    In accordance with a second aspect of the present invention, with reference to a first embodiment thereof illustrated in  FIGS. 8-10 , a variable flow attachment  34  is provided for coupling with breathable fluid delivery devices such as electronic cigarettes. Attachment  34  comprises a coupling adaptor  36  for attachment to the fluid delivery device (not shown), a variable valve  47  comprising a valve needle  49  cooperating with a valve seat  51  to throttle the portion of fluid passing through or around an exchangeable fluid permeable cartridge  38 , a cartridge housing  40  for retaining and supporting cartridge  38 , and a housing cover  42  comprising mating sections  44  and  46  for locking a fluid permeable cartridge into housing  40 , having also a channel  48  for receiving a mouthpiece  50 . Cartridge housing  40  is illustrated as integrally incorporating valve seat  51 . 
         [0091]    Attachment  34  may be constructed with various fluid delivery device coupling adaptors to permit use of attachment  34  with said devices at a connection point where a mouthpiece of existing such devices would normally be fitted, although not exclusively limited to such existing connection types. Thus, in the illustrated embodiment, coupling adaptor includes the same type of connection as mouthpiece  50 . To permit the passage of a fluid through attachment  34 , coupling adaptor  36  includes an open channel  52  spanning its internal length. The inner diameter of channel  52  is optionally but preferably similar to that of a mouthpiece for which the herein described auxiliary conduit assembly is substituted. The coupling adaptor may include attachment to an assembly for receiving multiple breathable fluid streams. 
         [0092]    Attachment  34  may take on various embodiments. Preferably, the valve system is able to partition a fluid flow either through or around cartridge  38 , allowing a user to select what portion of the total fluid flow is exposed to the functional fluid and what portion is not, to vary the intensity of the flavor or other functional effect in the inhaled stream. In the illustrated embodiment, a maximum intensity is delivered by fully seating valve needle  49  into valve seat  51  to close a bypass channel  54 , and a minimum intensity is delivered by withdrawing valve needle  49  to the farthest extent permitted by the device construction to provide the freest access to bypass channel  54 . The illustrated valve is adjusted by twisting a threaded connection between proximal housing cover section  44  and a valve housing  56 . Such a threaded connection is a convenient way to provide fine adjustment control, but other valve adjustment mechanisms, including relatively sliding components, may be alternatively provided. 
         [0093]    In other embodiments not shown, it may also be possible for a user to fully close the main channel that passes through the cartridge to reduce the intensity of the functional effect to essentially zero. For example, such a feature could be used to produce a “chaser” effect, if the functional liquid has an unpleasant taste, by a user quickly following a breath containing the functional fluid with a breath containing the base breathable fluid only, which may contain an agent that desirably masks or alters the flavor of the functional fluid. This throttling of fluid flow between the two flow paths would preferably be achieved by a valve system between the fluid entering through the open ended channel in the said fluid delivery device coupling adaptor and a housing associated with the coupling adaptor that is proximal to the valve. 
         [0094]    In still other embodiments not shown, a plurality of cartridges may be arranged in a device, either in parallel or in series, being disposed in one or more fluid flow pathways leading to one or more mouthpieces. Valve systems of such a device may include one or more valves similar to that of the illustrated embodiment, such as one valve for each cartridge, for example. The valve or valves may simply partition the inhaled fluid stream through or around a single one of the cartridges, or may variably distribute the stream between or among two or more of the cartridges, for variable selection of flavors, functions, or combinations thereof. 
         [0095]    For example, one or more cartridges as described and illustrated herein, optionally together with an electrically powered atomizer tank assembly, may be advantageously connected to each of a plurality of outlet lines of an otherwise conventional hookah (not shown). Thus, a breathable stream of air and smoke generated by the hookah may be passed through the cartridge, optionally together with atomized liquid from an atomizer tank assembly connected in line with the hookah, or in parallel with the hookah, such as via a lateral port of the hookah outlet line or via an additional parallel inlet to the cartridge.) 
         [0096]    Returning to the valve assembly illustrated in  FIGS. 8-10 , the illustrated valve is somewhat similar to a needle valve, but with valve needle  49  including an open ended channel  58  spanning its interior length. Interacting with valve needle  49  is valve seat  51 , which is illustrated as a tube into and out of which valve needle  49  can be drawn. In the embodiment illustrated in  FIGS. 8-10 , valve needle  49  is positioned adjacent coupling adaptor  36  and positioned upstream of valve seat  51 , while valve seat  51  is integral to cartridge housing  40 . This arrangement could also be reversed, generally as in the embodiment illustrated in  FIG. 11  as attachment  34 ′, including a valve needle  67  associated with a cartridge housing  69  and configured to insert in the proximal direction into a valve seat  71  associated with a coupling adaptor, or in the illustrated case, integrally formed in a coupling adaptor. However, the upstream/proximal position of valve needle  49  is believed to be slightly preferable for multiple reasons. For instance, baffling the bypass flow pathway to double back on itself, as illustrated by the arrows provides additional flow resistance and thus a finer adjustment of the bypass flow for a given amount of twist of the threaded valve assembly. Also, the doubled back bypass flow arrangement makes the parts easier to machine and injection mold, as well as improving the ease of handling of the fluid permeable cartridges, since they are larger and easier to manipulate with one&#39;s fingers. A long cartridge tube also makes it easy to load and unload the cartridge. 
         [0097]    An exchangeable cartridge porous packing, containing a functional fluid, impedes the flow of fluid through it to some extent. This flow impedance may be significant without departing from the scope of the invention, but it should not completely block the flow of fluid through the packing when a pressure differential is applied across its length. With respect to the measure of the pressure differential across the packing, in the preferred embodiment the pressure differential considered for intended function would correspond to a vacuum which could be comfortably provided by the intended user drawing in a breath through the device in normal atmospheric conditions. In certain variations and embodiments which could be envisioned by someone skilled in the art provided in this disclosure, the pressure differential measurement may be a value dependent upon other parameters and it is to be understood that various pressure differentials could be considered for design of the flow impedance of the packing to permit intended function of the variable valve system. 
         [0098]    With reference to  FIG. 8 , valve seat  51  is docked in a collar portion of section  44 , the collar portion including bypass channel inlet apertures  64  for permitting the free flow of fluid diverted around cartridge  38 . Under a pressure differential across the combined length of valve housing  56  and cartridge housing  42 , variable valve  47  facilitates the partitioning of fluid flow between the two flow paths in relation to the flow impedance of the cartridge packing and the cross-sectional area of a gap  61  that is present between valve needle  49  and valve seat  51  in partially open and fully open valve positions, as illustrated in  FIGS. 8   b  and  8   c . As a further aspect of variable flow attachments according to the invention, a structural relationship is provided to allow a user to draw the valve seat away from or onto the valve needle. As illustrated in  FIG. 8 , this is embodied as a movable connection between proximal cartridge housing cover section  44  and valve housing  56 , which may include a threaded connection between valve housing  56  and a proximal threaded end  60  of section  44 . Preferably the gap between the section  44  and valve housing  56  is sealed from fluid flow such as air leaks, by an O-ring or analogous suitable sealing structure mounted in a gasket seat  62  of proximal cartridge housing cover section  44 . Preferably, the O-ring or substituted structure would consist of a resilient material or any other suitable material that would be chemically compatible with the chemicals being passed through the channel between the needle valve, housing, and sleeve. 
         [0099]    Cartridge housing  40  cooperates with the interior of housing cover  42  to define bypass channel  54  to permit the flow of fluid around cartridge  38  to mouthpiece  50 . More specifically, the cartridge housing has an exterior diameter less than that of the interior diameter of the housing cover. Mixing of the bypass fluid stream with the fluid stream that passes through cartridge  38  occurs in a widened channel area  66  in fluid connection with the distal end of cartridge  38  and with bypass channel  54  via a reentry passage  68  formed in a portion of distal cartridge housing cover section  46 . 
         [0100]    In another embodiment of a variable-flow attachment according to the invention, illustrated in  FIGS. 12   a - 16 , an attachment  34 ″ that is functionally similar to attachment  34  is illustrated, including an improved valve adjustment feature. Attachment  34 ″ includes a cartridge  70  including an integral casing  71  with an integrally attached, tubular valve seat  72 , having a smaller bore diameter, extending proximally therefrom. Instead of a perpendicularly stepped profile as illustrated for cartridge housing  40  of attachment  34  described above, cartridge casing  71  includes an oblique tapered section  74  transitioning between its wider and narrower channels, so that essentially no portion of the proximal face of a circular cylindrical packing  73  inserted contained therein is blocked to flow of the breathable fluid in the distal direction. 
         [0101]    A distal cartridge casing cover section  76  and a proximal cartridge casing cover section  78  cooperate to enclose and retain cartridge casing  71 , section  76  being slidingly inserted into section  78 . The sliding connection between sections  76  and  78  is preferably sealed by O-rings  79 , depicted in  FIG. 12   b  as mounted in annular O-ring seat channels formed in the exterior of the inserted portion of section  76 . In its retained position, a distal end of cartridge  70  abuts a proximally facing annular interior end face  77  (seen in  FIGS. 15   a  and  15   b ) of section  76 , and the generally proximally facing exterior surface of tapered section  74  abuts a collar  80  of section  78 , essentially to prevent movement of cartridge housing  70  in either axial/longitudinal direction with respect to attachment  34 ″. Section  76  includes a distal channel  82  for carrying breathable fluid flow exiting from a cartridge  70  and for receiving a mouthpiece  84  inserted into its distal end. Section  78  is threaded into a coupling adaptor  86  which also includes an integral valve needle  88  having a channel  89  extending therethrough for permitting breathable fluid to pass from a delivery apparatus connected to coupling adaptor  86  into the interior of valve seat  72 . The connection between section  78  and coupling adaptor  86  is sealed by an O-ring  91 . 
         [0102]    A variable valve  90  comprising valve seat  72  and valve needle  88  serves to variably proportion the flow of a breathable fluid stream entering through coupling adaptor  86  between a main channel  92  extending through a cartridge in cartridge housing  70  and a bypass channel  94  passing around cartridge  70 . Similarly to the function of valve  47  of attachment  34 , breathable fluid is permitted to pass through variable valve  90  into bypass channel  94  only in a proportion permitted by a clearance (if any) between valve seat  72  and valve needle  88  is opened by withdrawing valve seat  72  from valve needle  88 . Valve  90  is depicted in  FIG. 12   b  in a fully closed position with no clearance between valve needle  88  and valve seat  72 , and thus all of the breathable fluid stream is constrained to pass through a cartridge (not shown) retained in cartridge housing  70 . When valve  90  is opened, breathable fluid is permitted to pass through a clearance between valve needle  88  and valve set  72 , through bypass channel inlet apertures  97  formed in collar  80  (shown in  FIGS. 12   b  and  13 ) into bypass channel  94 , and through a reentry passage  99  formed in distal cartridge housing cover section  76  (shown in  FIGS. 15   a  and  15   b ) to re-enter main flow channel  92 . 
         [0103]    Valve  90  is opened by a user unscrewing proximal cartridge casing cover section  78  from coupling adaptor  86  section  78  with a twisting motion facilitated by a rotatable ring portion  96  of section  78 , having a grip enhancing textured outer surface  98  with an exterior diameter larger than that of the adjacent exterior surfaces of distal cartridge casing cover section  76  and coupling adaptor  86 . 
         [0104]    Turning to  FIGS. 16   a - 16   c , cartridge  70  of attachment  34 ″, and an alternative cartridge  70 ′, are illustrated in detail. In  FIG. 16   a , cartridge  70  is shown to consist only of casing  71  and packing  73 . On the other hand, an alternative cartridge  70 ′, as depicted in  FIGS. 16   b  and  16   c , may include a distal fluid permeable end cover and/or sealant film  100 , and optionally a proximal sealant film  102 . Sealant film would serve the purpose of sealing functional liquid inside cartridge  70 ′ for shipping, handling, and/or storage, and any sealant film would be removed prior to use of cartridge  70 ′ in attachment  34 ″. 
         [0105]    Referring to  FIGS. 17 and 18 , an alternative coupling adaptor and valve assembly  104  (full assembly shown in Fig. for use in attachments similar to attachments  34 ,  34 ′, and  34 ″ is depicted as including a “clicking” mechanism, providing sensory feedback to a user to facilitate returning the valve assembly to a variable valve position that the user finds to his or her liking. In particular, valve assembly  104  includes a clicker element  106  accommodated between an alternative valve needle component/coupling adaptor  86 ′ and an alternative proximal cartridge casing cover section  78 ′ by features added thereto with respect to the illustrated coupling adaptor  86  and section  78  described and illustrated above. In particular, clicker element  106  is retained in and constrained to rotate with valve needle component  86 ′ by a mating connection between posts  108  of valve needle component  86 ′ and holes  110  in a proximal base of clicker element  106 , a central hole  112  in clicker element  106  at the same time accommodating valve needle  88  extending therethrough. Clicker element  106  further includes flexible arms  114  having radial clicking protrusions  116  at their distal ends. For insertion of section  78 ′ into valve needle component  86 ′, clicking protrusions  116  are aligned with and inserted into longitudinal slots  118  formed in the interior of section  78 ′. In the illustrated embodiment, there are four longitudinal slots  118  and two clicking protrusions  116 ; however, there may be as many longitudinal slots  118  as desired, or as few as one, although it is preferred that there be at least as many slots as protrusions, including protrusions arranged for simultaneously longitudinally receiving each protrusion. It is also preferred that slots  118  be evenly spaced apart, so that a number of clicks may provide a user with a tactile and auditory indicator of an amount of twisting corresponding to a desired variable valve position. When the threads (not shown) of section  78 ′ engage those of needle valve component  86 ′ and a user begins to twist the two together, a tactilely pleasing and informative clicking sound and sensation will occur each time a clicking protrusion snaps into one of slots  118 , corresponding in the illustrated embodiment to a quarter turn of rotatable ring portion  96 . 
         [0106]    In light of the present disclosure of the invention, one skilled in the art will appreciate that exchangeable porous cartridges as described above may be advantageously connected, attached, or incorporated into a wide range of inhalation devices, including medical or therapeutic devices as well as leisure/recreational devices, and including vapor-based inhalation devices but also smoke-based inhalation devices such as hookahs. 
         [0107]    According to one example, presented in  FIG. 19  is a schematic illustration of a complete inhalation device  120  incorporating the exchangeable porous cartridge and variable valve/throttled flow aspects of the invention. Inhalation device  120  includes a fluid-permeable cartridge component  122 , which may either be a cartridge with an integral valve seat or needle, or a cartridge housing with an integral valve seat or needle containing a cartridge therein, as illustrated and described in the foregoing embodiments, or some other equivalent structure, a distal cartridge housing or casing cover section  124 , and a breathable fluid delivering base section  126  of the device having a proximal cartridge housing cover section  128  and a valve needle or seat (not shown) included therein to mate with its seat or needle counterpart in the cartridge or cartridge housing. Base section  126  thus combines fluid delivery components such as a propylene glycol or vegetable glycerin tank (not shown) and a heating coil, vibrating element, or other atomizing element (not shown) with variable valve and cartridge retaining components or elements as described above, in a single body. Base section  126  may simply be the product of connecting a coupling adaptor such as coupling adaptor  86 , needle valve component/alternative coupling adaptor  86 ′, or an equivalent component or combination of components into a body including breathable fluid delivery components. Alternatively, base section  126  may include such valve and cartridge retaining components permanently integrated with part or the entirety of the fluid delivery portion of the device. 
         [0108]    In accordance with other aspects of the invention, various embodiments of a complete electronic cigarette assembly, advantageously incorporating exchangeable porous cartridges according to the invention and/or other aspects of the present invention, will now be described in greater detail. The disclosure presents an electronic cigarette assembly designed to emulate the sensory experience of smoking a tobacco cigarette, while also being equipped with a system for introducing a functional liquid into the fluid stream passing through the assembly. Illustrated in  FIGS. 20-24  is one example of a complete inhalation device incorporating a cartridge according to the invention. A preferred embodiment of a complete inhalation device further incorporating an adjustable, snap-locking throttle valve is illustrated in  FIGS. 25-28  and  35 .  FIGS. 34 ,  36 , and  37  illustrate in greater detail the electrical and atomizer tank components common to throttled and unthrottled embodiments of a complete device according to the invention. 
         [0109]    Turning to  FIGS. 20-24 , an illustrative electronic cigarette device  130  according to the invention includes an electrical control circuit comprising a battery  132 , an electronic controller  134 , a battery/controller housing  136 , and suitable connecting wires or other conductive elements (such as portions of a housing structure of the device or its individual components) that complete a circuit to permit current to flow through powered device components; an atomizer housing  138  defining an atomizing liquid storage chamber  140 , and an atomizing chamber  142  having an aperture  143 , which collectively define an atomizer tank assembly  145 , an exchangeable fluid permeable and porous cartridge  144 , a cartridge housing cover  146 , and a cartridge housing  148  for locking cartridge  144  into cartridge housing cover  146 . Cartridge housing cover  146  also includes a distal channel  150  for receiving a mouthpiece  152 , although a suitable cartridge housing cover may alternatively comprise an integrally formed mouthpiece. Cartridge  144  may advantageously take the form of any of the embodiments of an exchangeable porous cartridge described and illustrated above with reference to  FIGS. 1-18 . 
         [0110]    Battery  132  is preferably rechargeable and stores enough energy to power device  130  for many atomization cycles, avoiding the need to recharge with a frequency that a typical user would find inconvenient. Battery/controller housing  136  is preferably of a size to be comfortably held in an average adult hand, but by no means would be restricted to such a size. 
         [0111]    Electrical controller  134  controls the current and voltage delivered to an atomizing element  154  associated with atomizing chamber  142 . Voltage and current delivered may either be preset or user-defined, for example by user input entered via a display/control panel  156 , which may include a touch sensor and/or one or more buttons. In alternative embodiments, voltage and current may be supplied to more than one atomizing mechanism individually or simultaneously, such as when more than one atomizer tank analogous to an atomizer tank  158  (which comprises atomizer housing  138 , atomizing chamber  145 , and atomizing element  154 ) is included in a single device, or when the device includes an additional atomizing element associated with cartridge  144 . Voltage and current delivered may be the same or different for different atomizing mechanisms. Alternatively, an inhalation device according to the invention may include only one atomizing element associated with any suitable exchangeable, fluid permeable cartridge as described herein. In one example, atomizing liquid and functional liquid could be combined and atomized together from a single cotton wick surrounding an atomizing element. 
         [0112]    Current and voltage to the atomizing mechanisms may be actuated by a manual actuator  160 , preferably mounted to battery/controller housing  136 . Manual actuator  160  may comprise any type of mechanical switch, such as a push button as shown, or a slider, twist knob or collar; or an electro-mechanical switch, such as a touch screen or other touch sensor which may for example be comprised in display/control panel  156 . On the other hand, current and voltage actuation may be initiated automatically in response to a user drawing breath through the device, such as by a sensor (not shown) in line with fluid flow through the device detecting a fluid velocity, volumetric or mass flow rate, or pressure drop at or above a preset threshold, in response to which a control component causes the current and voltage to be delivered. Preferably, the sensor actuates the electrical current flow under a pressure drop that may be comfortably generated by a user drawing breath through the device. 
         [0113]    The electrical control circuit of the device may control an electronic user display, preferably mounted in the housing. Preferably, the electronic display is configured to display certain numerical values or other data relevant to the device settings, such as voltage, current, temperature of particular elements (such as atomizing elements for atomization liquids or functional liquids), usage data (such as times, dates, and durations of usage, stored settings, and power consumption history), battery charge levels, warnings, or other data of potential interest to a user. 
         [0114]    In one embodiment, the control circuit includes a memory storage element capable of recording and storing usage data relevant to the user, as well as any other information delivered to the device by means of electrical communication by either a direct wire connection or a wireless communication mechanism. This data may include, for example, cumulative consumption of the atomization liquid or functional component over a given time period; time period of fluid draw by the user; time periods between uses; temperature profiles of one or more components; power consumption history; stored preferences or settings; and alternate modes of use, such as previous combinations of components connected in the device assembly, and in what order they were connected, and/or particular encoded information identifying attributes of a component, such as its part or serial number, a flavor or substance that it contains or may contain, for example. Furthermore, the data stored may be used by processing units to control the mechanisms of the present invention. One skilled in the art will appreciate that these types of data are disclosed by way of example and should not be considered to limit the scope of information that may be stored in the memory storage element within the scope of the invention. 
         [0115]    Preferably, electronic controller  134  includes one or more processing elements/processors. For example, the processors could be used to determine what is displayed on display/control panel  156  and/or to actuate automatically atomizing element  154  or elements in accordance with data and logic processed by the processors. One skilled in the art will appreciate the diverse extensions of the use of processors in the present invention, which are by no means restricted to the processing examples disclosed herein. 
         [0116]    As an alternative to simple manual actuation or actuation triggered by a flow or pressure sensor, actuation of atomizing element  154  may occur automatically in response to the input of a passcode matching a valid passcode stored in a memory of controller  134 . Alternatively, a correct passcode entry may only “unlock” the atomization function of the device, without automatically initiating atomization, but instead permitting a user to actuate atomization manually. For instance, after the passcode is successfully validated, a user may press a simple button or switch to initiate atomization. The atomization element may respond to a single manual actuation following passcode validation, a predetermined plural number of manual actuations, for a predetermined amount of time elapsed after passcode validation, or until the processor receives an affirmative user command to “lock” the device again, such as by re-entry of a passcode to toggle back to a locked state, or by a simple manual switch or button. The password may be input by a user directly into display/control panel  156  or communicated to controller  134  from a separate input device or token, such as a user&#39;s personal smartphone, magnetic key card, bar code image, via a Wi-Fi, infrared, Bluetooth®, RFID, or optical connection, for example. 
         [0117]    In one embodiment, controller  134  may also include or be operatively linked to a wireless communication element (not shown) capable of transmitting to another wireless communication device or receive information from said wireless communication device. In general, many wireless network types are contemplated in this disclosure and may include, but are not necessarily limited to WPAN (Wireless Personal Area Network), WLAN (Wireless Local Area Network), WAN (Wide Area Network), or any other suitable wireless network and communication types. Advantageously, wireless network connectivity enables inhalation devices according to the invention to be controlled by a personal electronic device such as a smartphone, for purposes of passcode-enabled actuation or locking/unlocking of one or more functions of the inhalation device (obviating the need for a multi-key user interface on the inhalation device itself), as well as facilitating monitoring/tracking, storage, and analysis of usage data on the personal electronic device. 
         [0118]    Furthermore as an additional aspect of the electrical control circuit, preferably the circuit would be designed so as to be able to receive and transmit to battery  132  an electrical current from a charging lead, as well as including electrical communication elements for transmission of data between device  130  and external computation and/or data storage devices. In one embodiment, a connection port (not shown) at the proximal end of a battery/controller housing can be mated with other elements extending proximally therefrom. When included, such a connection port may also permit electrical communication from the circuitry to one or more atomizing elements. 
         [0119]    Advantageously, electrical controller  134  may be designed to regulate battery charge rate with respect to voltage and current and could prevent battery overcharge. Furthermore, preferably the electrical control element would prevent reverse polarity damage to the circuit elements or battery, by incorporating appropriately configured elements such as diodes, PNP Transistors, or a P-channel FET. 
         [0120]    As best seen in  FIG. 23 , atomizer housing  138  is connected between battery/controller housing  136  and cartridge housing cover  146  and contains a single atomizing element  154 . However, multiple atomizing elements may optionally be housed within a single atomizer housing. Other alternative embodiments of an atomizer housing may accept (or consist of) single or multiple exchangeable fluid permeable cartridges. Alternatively, an inhalation device may employ multiple atomization chambers and mechanisms, each adapted for atomization either of an atomizing liquid by itself or of an atomizing liquid and a functional liquid exclusively or simultaneously. Furthermore, the atomization of one or both of these liquid types may occur in distinct and separate atomization chambers, or in a combined atomization chamber. In other possible variations, an atomizing liquid and a functional liquid may undergo atomization in one chamber, a plurality of distinct chambers, in separate and distinct chambers simultaneously, in separate and distinct chambers at different times, both together in distinct chambers in addition to a separate chamber having one or both liquids, or both together combined and simultaneously atomized in separate and distinct chambers. 
         [0121]    Wherever an exchangeable cartridge is provided in one of the illustrated complete devices of the invention, at atomizing element may be incorporated into the exchangeable cartridge within the scope of the invention, with the benefit of promoting more complete or faster atomization of the functional liquid to be carried in the breathable fluid stream than may be achieved by simply passing the fluid stream through the cartridge. In effect, an atomizer cartridge  161 , as illustrated schematically in  FIG. 41 , or an atomizer cartridge  163 , as illustrated schematically in  FIG. 42 , may in general be used in place of any other exchangeable fluid permeable cartridge disclosed herein. Atomizer cartridge  161  includes a casing  165  holding a packing material  167  and supporting an atomizing element  169  in contact therewith, atomizing element  169  including electrical leads  171  and  173  for completing a circuit connecting atomizing element  169  to a battery generally through the interior of the inhalation device via lead  171  and along the conductive walls of one or more housing components via lead  173 . Atomizer cartridge  163  includes similar elements to those of cartridge  161 , its casing  165 ′ further including a functional liquid reservoir chamber  175  in fluid communication with a packing material  167 ′ via an aperture  180  for replenishing the functional fluid contained in packing material  167 ′ at a restrained rate, an aspect of certain fluid permeable cartridges according to the invention that will be described in more detail below, with reference to  FIGS. 32 and 33 . 
         [0122]    Atomizing element  154  is electrically connected to battery  132  by a contact pin  162  associated with atomizer housing  138  and atomizing element  154  contacting controller  134 , thus providing a controlled amount of current and voltage to atomizing element  154 . In turn, current flows from atomizing element  154  through conductive portions of atomizer housing  138  and of battery/controller housing  136  to return to battery  132 , completing a circuit. 
         [0123]    Atomizer housing  138  and neighboring components preferably define at least one atomizing liquid storage chamber, illustrated as storage chamber  140 , and at least one atomizing chamber, illustrated as atomizing chamber  142 . Liquid storage chamber  140  stores an atomizing liquid, to provide a consistent supply of the liquid to atomizing chamber  142  (at a restrained rate, through aperture  143 ), where the liquid enters into operative atomizing contact with atomizing element  154 . Atomizing chamber  142  is a fluid conduit assembly designed to receive a supply of fluid, deliver it to atomizing element  154  in a reliable fashion, and integrate a certain portion of the atomized liquid into the fluid stream passing through the conduit by way of atomizing chamber  142 . The path of breathable fluid flow through atomizer tank assembly  145  passes through the atomization element  154  and atomization chamber  142 , where it then is introduced into the flow paths entering the exchangeable cartridge and the diversion path, as illustrated by the arrows in  FIG. 23 . 
         [0124]    Liquid storage chamber is preferably constructed so as to prevent or inhibit unintended liquid leakage, but also to permit disassembly or alteration to allow a user to refill the atomizing liquid reserve. Desirable properties for materials of the chamber include chemical resistance, transparency, and structural strength and durability. Thus, one preferred material is polycarbonate. However, liquid storage chamber  140  may be constructed from any suitable material or materials chosen according to design specific parameters. 
         [0125]    A liquid storage chamber and an atomizing chamber may alternatively combined into a single conduit element wherein a liquid retaining material (e.g. an absorbing or adsorbing material), such as a fibrous material, stores an atomizing liquid, releasing the atomizing liquid into contact with an atomizing element over a controlled area of the atomizing element for introduction into a breathable fluid stream at a restrained rate. Furthermore in contact with the liquid storage material would be an element for delivery of the stored liquid to a single atomizing mechanism or multiple atomizing mechanisms. 
         [0126]    Atomizing element  154  may comprise electrically resistive wire, such as platinum, nichrome, or any other suitable metal alloy or material that may emit heat via electrical resistance, electrical induction, or any other comparable method for heat generation using a flow of electrons. Alternatively, atomizing element  154  may be a piezo-resistive nebulizer, pneumatic nebulizer, thin-film nebulizer, or any other mechanism whereby a said atomizing liquid and/or functional fluid may be aerosolized, nebulized, atomized, or otherwise introduced into a fluid air stream passing through the conduit channels of an inhalation device of the present invention. One or more of such atomizing mechanisms may be included within an atomizing chamber or elsewhere within the device. 
         [0127]    Variations are also possible in the manner in which the atomizing mechanism interacts with the atomizing liquid, and the accompanying structures that cooperate with the atomizing mechanism. For example, when the atomizing mechanism comprises an atomizing element such as a hot wire coil, a cotton or fiberglass wick may be associated with the coil in order to draw atomizing liquid into the coil for atomization via capillary action. Also, in such embodiments, a rolled sheet of fiberglass or similar material may be packed into the chamber to assist in wicking atomizing liquid to the coil. In piezo-resistive or thin film nebulizers, often a pool of atomizing liquid is associated with the nebulizer in order to supply the liquid to it. In some cases, the nebulizer may not be in direct contact with the atomizing liquid, but may act upon the liquid by way of a pulse wave carrier fluid or media, which then interacts with a thin flexible film which then transfers the pulse wave energy to the atomizing liquid and in turn nebulizes the liquid. Any of these exemplary mechanistic approaches may be incorporated into devices according to the present invention, but by no means is the present invention limited to these designs. In summary, said atomizing chambers are not limited to any particular atomizing mechanism or any particular cooperating structures or materials required for the proper function thereof. 
         [0128]    Advantageously, atomizer housing  138  is configured to connect in line with exchangeable porous cartridge  144  containing a functional liquid. Thus, the atomizer housing  138  preferably mates with cartridge housing cover  146  for receiving the cartridge, in which the cartridge is disposed in line with the fluid flow channel of the device, so as to expose the atomized fluid to the cartridge before the atomized fluid reaches a user. Preferably, a cartridge in housing cover  146  is retained in an easily accessible slot for toolless removal and replacement. A connecting feature for connecting cartridge housing cover  146  to atomizer housing  138  may be a threaded connection as shown, a tight fitting sliding connection, lined with one or more O-rings, permitting the housings to be pushed together and pulled apart by a user, or any other suitable connection. Preferably the housing cover would act to cover and fix into place the exchangeable porous cartridge as well as define a space for attachment of a mouthpiece, if a mouthpiece is not integrated into the housing or housing cover. 
         [0129]    In alternative embodiments of the exchangeable porous cartridge aspect of the invention, multiple cartridge pods, each pod comprising a packing material containing an absorbed or adsorbed functional liquid substantially as described with respect to the foregoing embodiments, may be incorporated into a single device. This may be done in many different ways, including, for example, by stacking multiple cartridges according to the foregoing embodiments, or by providing a single cartridge that houses multiple pods in a single casing. Thus, as illustrated in  FIG. 38 , a cartridge  164 , comprises a casing  166  housing a pod  168  and a pod  170 , each pod preferable comprising a porous, fluid permeable packing material containing an absorbed or adsorbed functional liquid. Pods  168  and  170  are hatched differently in  FIG. 38  to emphasize that they are separate bodies—they may or may not comprise a different packing material, and they may or may not contain a different functional liquid in their respective packing material. Although pods  168  and  170  are shown as stacked in line with the direction of fluid flow, two or more pods may alternatively be arranged in parallel, one benefit of a parallel arrangement being a lesser tendency of cross-contamination of functional liquids between the pods, particularly if the multiple pods are separated by a longitudinal barrier. The overall combined structure of cartridge  164  is fluid permeable, and its fluid mechanical functionality as a conduit element is similar to that of cartridges of the foregoing embodiments that include only a single pod or single mass of fluid permeable material, providing some resistance to a breathable fluid flow, but not so much as to prevent a user from comfortably inhaling breathable fluid through cartridge  164 . In other embodiments not shown, a plurality of exchangeable porous cartridges, each including its own corresponding throttle valve subassembly, may be stacked upon one another in the housing, to allow a user to integrate multiple functional liquids into the fluid flow in adjustable ratios. 
         [0130]    According to yet another embodiment of the fluid permeable cartridge aspect of the invention, illustrated in  FIGS. 32 and 33 , cartridges according to the invention may comprise separate chambers, including a reservoir chamber for retaining a reservoir of unabsorbed functional liquid, a functional fluid delivery chamber retaining a packing material for absorbing or adsorbing the functional liquid from the reservoir chamber for introduction into a breathable fluid stream flowing through the packing material, and a partition between the chambers, the partition permitting limited exposure of the liquid in the reservoir chamber to the packing material, to permit liquid in the reservoir chamber to traverse, penetrate, or bypass the partition at a restrained rate for gradual absorption or adsorption into or onto the packing material. 
         [0131]    Thus, in the example illustrated in  FIG. 32 , an exchangeable fluid permeable cartridge  172  includes an annular reservoir chamber  174  and a functional fluid delivery chamber  176  retaining packing material  177 , and a partition between chambers  174  and  176  is provided in the form of an impermeable barrier  178 , including a small aperture  180 . The illustrated arrangement permits fluid in reservoir chamber  174  to flow into fluid delivery chamber  176  by capillary action, so as to maintain saturation of packing material  177 , to enhance the performance of cartridge  172  by extending its usable lifetime and ensuring maximum saturation for as long as possible. Aperture  180  is illustrated as being located near an end of impermeable barrier  178  closest to a valve needle component  182  integrally formed in a casing  184  of cartridge  172 , which is characteristic of the proximal end of cartridges described in preceding embodiments, but not necessarily limited to being the proximal end of cartridge  172 . This position of aperture  180  is preferred to take advantage of a gravity feed of atomizing liquid into packing material  177  provided by a user holding cartridge  172  (or an inhalation device, attachment, or assembly incorporating cartridge  172 ) with its distal end pointing up. However, aperture  180  may be alternatively located elsewhere in barrier  178  within the scope of the invention. Also, in lieu of a single aperture  180  of a given size, a plurality of smaller apertures may be provided, distributed evenly or unevenly in any fashion along or around barrier  178 . 
         [0132]    In another aspect of multi-chambered, self-replenishing cartridges according to the invention, such a cartridge may include multiple porous materials having different porosities and wicking abilities. In particular, an intermediate material of lower permeability may be interposed between the liquid reservoir and a more highly permeable packing material. Advantageously, this arrangement inhibits overflow of the more highly permeable material by restraining the rate of absorption/adsorption of functional liquid into or onto the packing material. As an additional benefit, functional liquid may spread through the intermediate material in directions tangential to its interface with the packing material before entering the packing material, thus promoting more uniform absorption/absorption compared to an arrangement in which a smaller inlet area (for example, that corresponding to the area of aperture  180  in cartridge  172 ) of the packing material is exposed directly to the packing material. An example to illustrate this further aspect of a multi-chambered, self-replenishing cartridge according to the invention is shown in  FIG. 33 , wherein an exchangeable fluid-permeable cartridge  186  includes an annular reservoir chamber  188  and a functional fluid delivery chamber  190  retaining packing material  192 , a multi-layer partition between chambers  188  and  198  being provided in the form of an outer impermeable barrier  194  having an aperture  196  and an inner fluid-permeable skin  200 , skin  200  being less permeable than packing material  192 . 
         [0133]    With reference to  FIGS. 25-28 , in preferred embodiments of the present invention, housing components may be “locked” together so as to restrain or wholly prevent their separation. For instance, a movement to separate the components may be blocked by one or more opposed obstructing surfaces, which may or may not be oriented obliquely to the direction of separating movement, so that at least one of them cams the other out of the path of the separating movement when sufficient force is applied, depending on whether or not it is desired to permit manual separation of the components once they are connected together. 
         [0134]    For example, another embodiment of a complete inhalation device with a variable valve system is illustrated in  FIGS. 25  (transverse cross-sectional elevation view) and  28  (exploded view) as inhalation device  199 . As shown in  FIGS. 26 and 27 , housing components that are moved relative to each other to adjust a valve position may “lock” together at a position of maximum relative separation defined for normal use, from which position it is relatively easy to draw the components closer together, up to a fully engaged position in which abutting end faces prevent further approaching movement. Drawing the components apart from the maximum separation position may be either restrained (as illustrated in the figures) or prevented outright. 
         [0135]    Thus, in  FIG. 26  a throttle valve assembly  201  is shown in which a cartridge housing  202  is slidingly received by a collar  204  disposed between cartridge housing  202  and an atomizer tank subassembly  208 . Collar  204  incorporates a valve seat  210  mating with a valve needle component  212  integral to a cartridge casing  214  retained within a cartridge assembly comprised of housing  202  and a cartridge housing cover  215 . Housing  202  includes a first o-ring seat  216  for seating a snap o-ring  218  and a second o-ring seat  220  for seating a compressible o-ring  222 . An interior annular surface of collar  204  includes a smaller diameter skid region  224  for slidingly engaging o-rings  218  and  222  and a larger diameter retaining groove  226  into which snap o-ring  218  snaps when it reaches the lower/proximal end of skid region  224  as a user slides housing  202  into collar  204 . The snapping mechanism may comprise, for example, snap o-ring  218  being a relatively stiff collar (of a material such as spring steel or a similar or equivalent material) that is less than a complete annulus, permitting it to compress to a smaller diameter and spring back to a larger diameter. A user will feel and/or hear the snap of o-ring  218  into retaining groove  226 , in addition to feeling reduced resistance to inserting movement of housing  202  into collar  204 , from compressible o-ring  222  alone sliding over skid region  224 , thus providing multiple sensory indications that valve assembly is properly connected and within its normal range of adjusting movement. Conversely, a user will also feel an increased resistance to pulling the components of throttle valve subassembly  201  apart past the most open valve position in the freely adjustable range, in which snap o-ring  218  makes contact with a proximal edge of skid region  224 , as most clearly shown in  FIG. 35 . 
         [0136]    Turning to  FIG. 27 , an alternative threaded snap-locking throttle valve subassembly  201 ′ is depicted, corresponding to an alternative inhalation device  199 ′ shown in exploded view in  FIG. 28 , including a threaded cartridge housing  202 ′ that threads into a threaded collar  204 ′ linking to atomizer tank subassembly  208 . Threaded collar  204 ′ incorporates valve seat  210  mating with valve needle component  212  of cartridge casing  214 . Like housing  202 , housing  202 ′ includes a first o-ring seat  216 ′ for seating a snap o-ring  218 ′ and a second o-ring seat  220 ′ for seating a compressible o-ring  222 ′. An interior annular surface of threaded collar  204 ′ includes a smaller diameter skid region  224 ′ and a larger diameter retaining groove  226 ′. The snap-locking mechanism of threaded throttle valve subassembly  201 ′ functions analogously to that of sliding throttle valve subassembly  201 . 
         [0137]    It should be appreciated that the variable valve system may not be restricted to the herein disclosed needle valve mechanism, but may comprise any mechanistic design that is capable of achieving the desired function described herein. 
         [0138]      FIGS. 29-31  illustrate further aspects of exchangeable fluid-permeable cartridges according to the invention, embodied in cartridges  256 ′,  256 ″, and  256 ′″ respectively, each of which includes an integral valve needle portion  258 ′,  258 ″,  258 ′″. With reference to  FIG. 29 , cartridge  256 ′ houses a packing material  260 ′ in a casing  262 ′ having open distal end  264 . Cartridge  256 ″, shown in  FIG. 30 , houses a packing material  260 ″ in a casing  262 ″ having a cover with a small-diameter aperture  266  at its distal end. Small-diameter aperture  266  advantageously restrains functional fluid from leaking or evaporating through the distal end of casing  262 ″, while also limiting the distal end face area of packing material  260 ″ that is exposed to open air and possibly contaminants while being inserted into or removed from an inhalation device, handled, or stored by a user. Relatedly, end sealing films, preferably with pull tabs for easy removal, such as films  267  and  269  depicted in  FIG. 31 , may be applied to a cartridge  271 , as a further measure to retain functional fluid, prevent contamination, and maintain freshness prior to commencement of use. 
         [0139]      FIGS. 39 and 40  depict alternative embodiments of exchangeable atomizer tanks, with separable and built-in atomizing elements, respectively. Advantageously, exchangeable atomizer tanks facilitates alternation between atomizing liquids (such as liquids having different flavors, for example) by switching out one partially used tank for another, as well as permitting disposal and replacement of relatively cheap to manufacture tank components, typically made of plastic, of an atomization system with new, optionally prefilled components. 
         [0140]    Referring to  FIG. 39 , an exchangeable atomizer tank assembly  274  is depicted, arranged between a battery/controller connector  275  and another assembly component  277  (which may for example be an exchangeable fluid-permeable cartridge housing), in which two distinct atomizing elements  276  and  278  are placed in line and in electrical communication with each other. Exchangeable atomization reservoirs  280  and  282  can slidingly fit over atomization chamber  284  and provide atomization liquid to the individual atomization elements. Flow of the liquid to the atomization elements may be initiated by piercing a liquid tight septum (not shown) in atomization reservoirs  280 ,  282 , for which a suitable piercing tool (not shown) may be movably incorporated into a component of or otherwise provided with assembly  274 . The septum may for example be any suitable film or membrane composed of a suitable material such as silicone, rubber, plastic, or metal foil, covering a flow channel inside the reservoir. Reservoirs  280 ,  282  may be exchangeable and disposable to allow a user to exchange atomization liquids without the need to clean or remove residues from previous liquids used in reservoirs  280 ,  282 . Additionally, reservoirs  280 ,  282  preferably employ a mechanism for liquid delivery to the atomization elements that permits a user to remove an atomization reservoir without liquid leaking at any reservoir liquid level or state, such as by a spring-loaded valve mechanism (not shown) that is biased to a closed state when  280 ,  282  are removed from the assembly. 
         [0141]    Turning to  FIG. 40  an alternative exchangeable atomizer tank assembly  286 , including distinct, preferably exchangeable and disposable atomization reservoirs  288  and  290  having associated within them distinct atomization chambers and atomization elements (not shown), arranged between a battery/controller connector  292  and another assembly component  294 . In such an arrangement, atomization reservoirs  288  and  290  may be assembled adjacent each other in series as depicted, or alternatively, having one or more other components disposed between them (not shown), such as an exchangeable fluid permeable cartridge according to the invention, with or without an associated atomizing element. Reservoirs  288  and  290  are electrically connected in series or in parallel as desired. Electrically resistive elements associated with reservoirs  288  and  290 , or interposed between them, may be provided to permit a user to selectively choose the amount of electrical current permitted through each atomization element in each reservoir. Such resistive elements (not depicted) could be separate and exchangeable elements that are placed in between each reservoir in order to permit a user to selectively control the atomization quantities provided from each atomization element. Reservoirs  288  and  290  are preferably in fluid communication with each other, either in series or parallel, to deliver atomized liquid from each reservoir into a breathable fluid stream passing through an inhalation device according to the invention. 
         [0142]    While the invention has been described with respect to certain embodiments, as will be appreciated by those skilled in the art, it is to be understood that the invention is capable of numerous changes, modifications and rearrangements, and such changes, modifications and rearrangements are intended to be covered by the following claims.