Abstract:
A vaporization system for an inhalable substance includes a sealed cartridge. The sealed cartridge contains the chemical solution to be vaporized, a heating element which vaporizes the solution, and a wicking material for retaining the solution and bringing it into contact with the heating element through capillary action. The sealed cartridge may be disposable, having inexpensive elements so the cartridge can be replaced with little cost. Alternatively the sealed cartridge may be fully integrated with other components into a base unit, which may be disposable or may include a refill port which allows a user to refill the sealed cartridge with solution once the contained solution has been fully vaporized. A power source connects to the heating element and is activated by a switch that may be a breath detector. A disposable mouthpiece may be connected to the cartridge. The mouthpiece has an airway through which the vaporized solution is inhaled. The airway is restricted by a trap that prevents unvaporized droplets of the solution from passing through the airway into a user&#39;s mouth.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of co-pending provisional application No. 61/124,114 filed Apr. 11, 2008. 
     
    
     FIELD OF INVENTION 
       [0002]    This invention relates to inhalation devices. This invention relates particularly to a low-cost electronic vaporization system for an inhalation device that prevents leakage of the substance to be vaporized. 
       BACKGROUND 
       [0003]    The delivery of chemicals, particularly medicaments and other compounds having a physical or physiological effect on a person, can be accomplished by vaporizing a solution containing the desired elements; the vapor is then inhaled by the user, whereby the desired elements enter the user&#39;s blood stream through the lungs. The solution is typically vaporized by bringing it into contact with a heating element. Where the chemical compound is contained in a plant, this delivery method is often preferred to burning the plant because it eliminates the ingestion of smoke and other combustion byproducts, which can have negative health effects and also create a foul taste. Vaporization may also allow ingestion of very small quantities of a chemical compound which is poisonous to humans in larger quantities. 
         [0004]    An example of such a compound is nicotine. Nicotine is known to have therapeutic effects in humans, for example as an anti-inflammatory and in treatments for some brain and neurological disorders. However, nicotine is typically ingested through cigarettes or chewing tobacco, which have other harmful, even carcinogenic, chemicals in them. Liquid nicotine does not have these chemicals in it, but it is easily absorbed through the skin. Because it is so poisonous, accidental contact can be fatal. Some existing vaporization systems store liquid nicotine in media which is prone to leakage. Further, some of the unvaporized solution may enter the airway that transports the vapor to the user&#39;s mouth, which the user may then suck out of the system into his mouth by inhaling. A nicotine delivery system that eliminates the negative effects of combustion and cigarettes, and also protects the user from leakage or inhalation of the nicotine-containing solution, is desired. Such a system would be equally applicable to other chemical compounds, whether dangerous or not. 
         [0005]    Existing vaporization systems designed for personal use suffer from contamination problems. Once a user vaporizes a solution, residue may collect in the system. If the user then desires a different solution, the vapors of the second solution may be contaminated by chemicals or flavors left over from previous uses. A system which allows the user to dispose of potentially contaminated components is desired. Such a system should also be inexpensive, to allow the user to purchase new parts without significant cost. 
         [0006]    Therefore, it is an object of this invention to provide a vaporization system that is safer to use than existing systems. It is a further object that the system allow the user to easily and inexpensively eliminate contaminants. Another object of this invention is to provide a sealed vaporization cartridge that limits usage to the solution contained therein and can be constructed and replaced without significant cost. 
       SUMMARY OF THE INVENTION 
       [0007]    Various embodiments of a novel vaporization system include a sealed cartridge. The sealed cartridge contains the chemical solution to be vaporized, a heating element which vaporizes the solution, and a wicking material for retaining the solution and bringing it into contact with the heating element through capillary action. The solution cannot escape the cartridge in liquid form. 
         [0008]    A base unit includes a power source which connects to the heating element, a switch for activating the power source, and an air port which connects to an airway through the sealed cartridge. In one embodiment, the sealed cartridge plugs into the base unit and is unplugged and disposed of when all the solution has been vaporized. The elements of the sealed cartridge are inexpensive so the cartridge can be replaced with little cost. In another embodiment, the sealed cartridge is fully integrated with the base unit, forming a one-piece unit. The one-piece unit may be disposable, or alternatively may include a refill port which allows a user to refill the sealed cartridge with solution once the contained solution has been fully vaporized. 
         [0009]    A disposable mouthpiece may be connected to the cartridge. In a one-piece unit the mouthpiece is integrated into the base unit. The mouthpiece has an airway through which the vaporized solution is inhaled. The airway is restricted by a trap which prevents droplets of the solution which are not fully vaporized from passing through the airway into a user&#39;s mouth. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a perspective view of the sealed cartridge of the present invention, with part of the shell cut away to show the vaporizing system. 
           [0011]      FIG. 2   a  is a perspective view of the preferred embodiment of the sealed cartridge with part of the shell cut away to show the vaporizing system. 
           [0012]      FIG. 2   b  is a perspective view of an alternate embodiment of the sealed cartridge with part of the shell cut away to show the vaporizing system. 
           [0013]      FIG. 2   c  is a perspective view of an alternate embodiment of the sealed cartridge with part of the shell cut away to show the vaporizing system. 
           [0014]      FIG. 3   a  is a perspective view of one embodiment of the vaporizing system. 
           [0015]      FIG. 3   b  is a perspective view of another embodiment of the vaporizing system using graphite rods. 
           [0016]      FIG. 3   c  is a side sectional view of another embodiment of the vaporizing system. 
           [0017]      FIG. 4  is a perspective view of the sealed cartridge connected to the mouthpiece. 
           [0018]      FIG. 5  is a perspective sectional view of an inhalation device. 
           [0019]      FIG. 6   a  is a side view of the section of  FIG. 5 , showing the switch. 
           [0020]      FIG. 6   b  is an exploded perspective view of an alternate embodiment of the switch. 
           [0021]      FIG. 7  is a perspective view of a one-piece inhalation device. 
           [0022]      FIG. 8  is a side sectional view of a one-piece inhalation device taken along line A-A of  FIG. 7 . 
           [0023]      FIG. 9  is a perspective view of a sealed cartridge with a recharge port. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]      FIG. 1  illustrates a sealed cartridge, designated generally as  10 , for containing a solution to be vaporized. The cartridge  10  is insertable into and removable from a compatible inhalation device, allowing for easy replacement when the solution is exhausted or the functionality of the cartridge  10  begins to degrade. The cartridge  10  is sealed to prevent leakage of the solution inside until the cartridge  10  is to be used, allowing for safe handling of the cartridge  10  by a user. A compatible inhalation device, such as those described below and illustrated in the figures, has a power source with terminals that align with the cartridge  10  when it is inserted into the inhalation device, creating an electrical contact that allows the user to activate the device and vaporize the solution in the cartridge  10 . 
         [0025]    The cartridge  10  has a shell  11  with a base  12  and a cap  13  attached to the shell  11  to create a hollow space therein. The hollow space contains a vaporizing system  20  for storing and vaporizing the solution. The cartridge  10  also comprises at least one air intake aperture  15  and at least one vapor release aperture  16 . The cartridge  10  may also comprise a heat-dissipating sleeve  18  in contact with the outer surface of the shell  11 . 
         [0026]    The shell  11  may be a chemically inert, non-porous material, including but not limited to metal, certain polymers, glass, and ceramic. The shell  11  material is chemically inert so as not to alter the solution to be vaporized, and non-porous so as not to absorb the solution in the cartridge  10 . The shell  11  material may conduct heat but should be resistant to deformation at typical vaporization temperatures. Preferably, the shell  11  is brass. The base  12  and cap  13  are also non-porous and heat resistant. The cartridge  10  preferably has a round or elliptical cross-section and is most preferably cylindrical. The points of attachment between the shell  11  and the base  12  and cap  13  are watertight and preferably also airtight. The base  12  and cap  13  may be the same material as the shell  11  so that a single mold may cast the three pieces as a single piece, or they may be a different material that can be adhesively attached to the shell  11 , such as metal or non-porous plastic, or non-adhesively attached to the shell  11 . The apertures  15  and  16  may be integrated into one or more of the shell  11 , base  12 , and cap  13 , or they may be added after the cartridge  10  is sealed with the solution inside. Preferably, the apertures  15  and  16  are cut into the shell  11  and cap  12  in the locations shown in  FIG. 2   a  after the cartridge  10  has been assembled and sealed. The apertures  15  and  16  may then be covered with a material, completely sealing the cartridge  10  until it is ready for use. The covering material may be a thin sheet of plastic or metal, such as aluminum foil. A compatible inhalation device is configured to puncture the covering material when the cartridge  10  is inserted, providing airflow through the cartridge  10 . For example, the inhalation device may have protrusions (not shown), such as plastic tabs or small metal spikes, aligned with the apertures  15  and  16  in order to puncture the covering material. Alternatively, the user may manually remove the covering material before inserting the cartridge  10 . The vapor release aperture  16  may be slot-shaped, as shown in  FIG. 2   a , to prevent unvaporized droplets from escaping the sealed cartridge, or may be round as shown in  FIG. 2   c  if unvaporized droplets are not a concern. An additional drop-catching structure (not shown) may be integrated into the vapor release aperture  16 . 
         [0027]    Referring to  FIGS. 2   a - c , the vaporization system  20  may comprise a heating element  21 , one or more reservoirs  22  for storage and wicking of the solution, and a heat retention structure  23 . The heating element  21  may be a metal alloy comprising at least nickel and chromium. Preferably, the heating element  21  is at least one nickel chromium wire which runs through the center of the cartridge  10 . The wire may be a single strand or several strands braided together, and may be any gauge that can reach the desired temperature without degrading. Preferably, the heating element  21  comprises three strands of 34-gauge nickel chromium wire, braided loosely to provide additional capillary action for bringing the solution into contact with the heating element. The ends of the heating element  21  serve as the electrical contact points for conducting a current through the heating element  21 . Upon insertion of the cartridge  10 , the ends align with the terminals of the power source in the inhalation device. 
         [0028]    A reservoir  22  is made of a porous media that stores the solution when the heating element  21  is not activated, and transports the solution toward the vaporizing heat by capillary action when the heating element  21  is activated. The reservoir  22  prevents leakage of the solution, in liquid form, through any aperture in the cartridge  10 . Preferably, the reservoir  22  is a sheet of nickel foam, cut to fit and then rolled around the heating element  21  to form a cylinder, such that the heating element  21  runs through the reservoir substantially parallel to the reservoir&#39;s  22  axis. The reservoir  22  may be a different shape in alternate embodiments, such as a sphere, box, or sheet. There are preferably two reservoirs  22  of nickel foam separated by a short distance, with the heating element  21  spanning the distance so that the vaporization system forms a “dumbbell” shape. This dumbbell shape provides adequate storage for the solution while maximizing the capillary surface area of each reservoir  22  so that the solution may be wicked to the heating element  21  from both ends of each reservoir  22 . Nickel foam is available in several densities, which may be combined within the vaporization system  20  to facilitate better storage, wicking, or both. Preferably, the nickel foam has a thickness in the range of about 1.7 to 2.2 millimeters and a density of between 320 and 1450 grams per square meter, with a pore size of between 450 and 800 microns. More preferably, the nickel foam is selected from one of the following groups of thickness, density, and pore size, respectively: 1.7 mm, 320 g/m 2 , and 590 microns; 1.7 mm, 420 g/m 2 , and 450 microns; 1.7 mm, 420 g/m 2 , and 580 microns; 2.2 mm, 800 g/m 2 , and 800 microns; and 1.7 mm, 1450 g/m 2 , and 580 microns. The nickel foam may have the same or different densities in each reservoir  22 . 
         [0029]    The heat retention structure  23  is a semi-porous, heat-retaining material, such as ceramic, porcelain, or alumina, which encircles all or a portion of the heating element  21  within the cartridge  10 . The porous aspect of the material may also be artificially created, such as by perforating the material. The heat retention structure is preferably rigid, semi-porous, unglazed ceramic. When the heating element  21  is activated, the heat retention structure  23  intensifies the heat generated within the heat retention structure  23  while partially insulating the space outside the heat retention structure  23 . In the preferred embodiment, shown in  FIG. 2   a , the heat retention structure  23  is a tube which encircles a portion of the heating element  21 , one of the reservoirs  22 , and the gap between the reservoirs  22 . In an alternate embodiment, shown in  FIG. 2   b , the heat retention structure  23  is a tube that encircles only the heating element  21 , separating it from the reservoirs  22 . In another alternate embodiment, shown in  FIG. 2   c , the heat retention structure  23  is a tube which encircles part of the heating element  21  and one of the reservoirs  22 , but does not enclose the gap between the reservoirs  22  so that the heat generated by the part of the heating element  21  in the gap will dissipate throughout the space within the shell  11 . 
         [0030]      FIGS. 3   a - c  illustrate different embodiments of the vaporization system  20 .  FIG. 3   a  shows the dumbbell embodiment described above. The two reservoirs  22  may be separated by a spacer  30  which maintains exposure of the surface area of each reservoir  22 . The spacer  30  may be an insulator, and is preferably the same material as the heat retention structure  23  so as to focus the capillary action of the reservoir  22  toward the center of the heating element  21 . The leading end  32  and trailing end  33  of the heating element  21  act as the electrical contacts for passing current and thereby heating the heating element  21 . The leading end  32  of the heating element  21  may be covered by wire insulation  31  as it enters the cartridge  10  through the cap  13 . The trailing end  33  of the heating element  21  may exit the cartridge  10  through the cap  13  as shown, but preferably meets the base  12 . The leading end  32  and the base  12  then make electrical contact with the terminals of the power source upon insertion into the inhalation device. 
         [0031]    Referring to  FIG. 3   b , the heating element  21  comprises two graphite rods connected to opposite polarities and heated to vaporize the solution. A heavier density reservoir  36  stores the solution and provides initial capillary action, while a lighter density reservoir  37  interposed between the heavier density reservoir  36  and the heating element  21  serves as the main wick, having greater capillary action than the heavier density reservoir  36 . 
         [0032]    Referring to  FIG. 3   c , the heating element  21  is a wire made of nickel chromium, coiled and encapsulated in a heat retention structure  23 . The reservoir  22  is wrapped around the heat retention structure  23 . 
         [0033]      FIG. 4  illustrates the preferred embodiment of the cartridge  10  attached to a mouthpiece  40 . The mouthpiece  40  may be wood, ceramic, porcelain, glass, rubber, or plastic, and may be assembled or cast from a mold as a single piece. Preferably, the mouthpiece  40  is vulcanized rubber cast from a mold. The mouthpiece includes an open end  41  which accepts the cartridge  10 , an airway  42  extending between an inlet  43  and an outlet  44 , and a p-trap  45  surrounding the inlet  43 . The p-trap  45  is designed to catch unvaporized droplets of the solution so they do not pass through the airway  42  into the user&#39;s mouth. The p-trap  45  may be integrated into the mouthpiece  40  or may be a separable piece which can be replaced if its performance degrades due to use. In the preferred embodiment, the cartridge  10  and mouthpiece  40  are designed to be disposed once the contained solution is fully vaporized. Alternatively, the mouthpiece  40  may be integrated into the inhalation device, as discussed below. 
         [0034]    Referring to  FIG. 5 , in the preferred embodiment the mouthpiece  40  attaches to the cartridge  10 , which is then inserted into the inhalation device  50 . The inhalation device  50  may be portable or non-portable, but is preferably portable. Preferably, the inhalation device  50  is shaped like a cigarette, having a long, cylindrical case  51  as shown in  FIG. 5 . The inhalation device comprises electrical terminals  52 ,  53  which connect to the leading end  32  and trailing end  33  of the heating element  21  when the cartridge  10  is inserted. The electrical terminals  52 ,  53  pass through a switch  60  and connect to a power source  54 . In non-portable embodiments, the power source  54  may be standard mains. In the preferred, portable embodiment, the power source  54  is a battery contained within the case  51 . The inhalation device  50  may have an air inlet (not shown) which, upon insertion of the cartridge  10 , aligns with the air inlet  15  on the cartridge  10  to facilitate the flow of air through the cartridge  10  into the user&#39;s mouth. The end of the inhalation device  50  opposite the mouthpiece  40  may include an ash emulator to give the user the impression of smoking a cigarette. The ash emulator may comprise a cover lens  55  and a light emitting diode  56  which activates in conjunction with the heating element  21 . The combination of cover lens  55  and diode  56  resemble the tip of a burning cigarette when lit. 
         [0035]    Within the switch  60 , a response structure  61  changes state when the user inhales through the mouthpiece  40 , and changes state again after a predetermined period passes or when the user stops inhaling. Logic boards  62  detect the state change in the response structure  61  and activate or deactivate the heating element  21 . The predetermined period for heating the heating element  21  may be stored in the logic boards  62  and may be based on the desired dosage of vaporized solution in a single inhalation. The logic boards  62  may also store usage information including the number and frequency of inhalations, the amount of solution delivered per inhalation, and power requirements that are specific to the type of solution contained in the cartridge  10 . The usage information can be used to enable and disable the device and to indicate to the user when the cartridge  10  should be changed. The logic boards  62  may receive the usage information from the cartridge  10  by communication means such as radio frequency identification (“RFID”) technology incorporated into the logic boards  62  and an RFID chip attached to the cartridge  10 . 
         [0036]    The response structure  61  can be any switching mechanism that responds to a user inhaling through the mouthpiece  40 , such as a reed switch, air pressure sensor, temperature sensor, or condensation sensor, or alternatively can be an external user-actuated switch such as a mechanical push-button or a capacitor-based touch sensor. In the preferred embodiment of the response structure  61 , shown in  FIG. 6   a , a reed switch  63  is in close proximity to a magnet  64 , but not close enough to magnetize the reed switch  63  and cause it to close. The magnet  64  is attached to a diaphragm  65 . When the user inhales, the diaphragm expands, pushing the magnet  64  toward the reed switch  63  and causing a state change in the reed switch  63 , namely closing the contact and alerting the logic boards  62  that the user is inhaling. In an alternate embodiment of the response structure  61 , shown in  FIG. 6   b , a non-magnetic tube  71  contains the magnet  64 , a spring  72 , and a physical stop  73 . The reed switch  63 , not shown in  FIG. 6   b , is positioned beneath the non-magnetic tube  71 . In the deactivated state, the spring  72  pushes the magnet  64  against the physical stop  73  and holds it there. When the user inhales, the magnet  64  is pulled by the force of the user&#39;s inhalation until it magnetizes the reed switch  63 , closing the contact and alerting the logic boards  62  that the user is inhaling. 
         [0037]    The inhalation device  50  may include the mouthpiece  40  so that the inhalation device  50  is self-contained except for the insertable cartridge  10 .  FIGS. 7 and 8  illustrate a simplified, one-piece inhalation device  80  which has a manually-activated power switch  81  that the user presses with a finger or thumb. The power source  54  may be permanently disposed within the one-piece inhalation device  80  and may be rechargeable by way of charging ports  82 ,  83 . The cartridge  10  may be inserted through a cartridge hatch  84  which is integrated into the outer contours of the one-piece inhalation device. The exterior surfaces may be partially or fully covered by a textured material  85  to facilitate gripping the device  80  in the user&#39;s hand. An indicator light  86  notifies the user that the power is on and may be a light-emitting diode or other low-cost indicator. 
         [0038]    In an alternate embodiment, shown in  FIG. 9 , the sealed cartridge  10  may comprise a refill port  100  which allows the user to add solution to the fluid reservoir  14  as needed. The refill port  100  is a resealable port that accepts a depositor (not shown) but does not allow air or fluid to escape the cartridge  10 . Preferably, the refill port  100  is made of rubber and functions like a standard rubber valve-and-needle inflation mechanism found on recreational inflatable balls. 
         [0039]    While there has been illustrated and described what is at present considered to be the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the true scope of the invention. Therefore, it is intended that this invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.